Bakery waste supplementation to late gestating Bos indicus-influenced beef cows successfully impacted offspring postnatal performance

Abstract

This study evaluated the growth and immune function of beef calves born to cows supplemented with bakery waste containing two concentrations of crude fat. On day 0 (~90 d before calving), 108 multiparous Brangus crossbred cows were stratified by body weight (BW; 551 ± 65 kg) and body condition score (BCS, 5.5 ± 0.9) and randomly allocated into 1 of 18 bahiagrass (Paspalum notatum) pastures (6 cows and 4.3 ha per pasture). Treatments were randomly assigned to pastures (6 pastures per treatment) and consisted of no prepartum supplementation (NOSUP) and isocaloric and isonitrogenous supplementation of low-fat (LFAT; 6.4% crude fat) or high-fat (HFAT; 10.7% crude fat) bakery waste from days 0 to 70 (1 kg DM per cow per day). Calves were weaned on day 292 (201 ± 17 d of age). Then, 15 heifers per treatment were randomly selected and assigned to drylot pens from days 300 to 345 and vaccinated against respiratory pathogens on days 300 and 315. Cow BCS near calving (day 70) was the least (P ≤ 0.05) for NOSUP cows and did not differ (P = 0.12) between LFAT and HFAT cows. Cow BCS at the start of the breeding season (day 140) was greater (P = 0.05) for HFAT vs. NOSUP cows and intermediate (P ≥ 0.35) for LFAT cows. Plasma concentrations of total polyunsaturated fatty acids in HFAT cows did not differ (P ≥ 0.76) compared with LFAT cows but were greater (P ≤ 0.05) compared to NOSUP cows on day 70. Final pregnancy percentage did not differ (P ≥ 0.26) among treatments, but a greater percentage of HFAT cows calved (P ≤ 0.05) their second offspring during the first 21 d of the calving season compared to NOSUP and LFAT cows (bred by natural service). Weaning BW was the greatest (P ≤ 0.05) for LFAT and least for NOSUP calves. Maternal treatments did not impact (P ≥ 0.11) postweaning growth and total DM intake of calves. Average plasma cortisol concentrations were greater (P = 0.03) for NOSUP vs. HFAT calves and intermediate for LFAT calves (P ≥ 0.26). Serum titers against infectious bovine rhinotracheitis and bovine respiratory syncytial virus were greater or tended to be greater (P ≤ 0.08) for HFAT vs. LFAT calves and intermediate (P ≥ 0.27) for NOSUP calves at the end of preconditioning. Thus, supplemental fat concentration fed to late-gestating beef cows had variable effects on calf performance. Low-fat bakery waste led to the greatest calf preweaning growth, whereas high-fat bakery waste enhanced maternal reproduction and had minor benefits to calf humoral immune function.

Bakery waste supplementation to late-gestating beef cows modulates offspring preweaning growth and immune function according to its crude fat concentration.

Introduction

Maternal prepartum supplementation of protein, energy, and other specific nutrients, such as polyunsaturated fatty acids (PUFA) ω-6 fatty acids (e.g., as linoleic acid), has been shown to improve postnatal calf performance (Cappellozza et al., 2021; Moriel et al., 2021) but has been evaluated to less extent in Bos indicus-influenced beef cows (Cooke et al., 2020; Moriel et al., 2021). Most studies reported that maternal prepartum supplementation of protein and energy enhanced offspring preweaning growth and postweaning immune function (Moriel et al., 2021). In contrast, maternal prepartum supplementation of Ca salts of ω-3 and ω-6 fatty acids resulted in no differences (Marques et al., 2017; Brandão et al., 2020; Shao et al., 2023), increased (Bellows et al., 2001; Ricks et al., 2020), or decreased (Shao et al., 2021a) offspring weaning weight compared to supplementation of saturated (SFA) and monounsaturated fatty acids (MUFA) or no fat supplementation. These inconsistent outcomes may be associated with different amounts and profiles of fatty acids reaching maternal intestine and fetal tissues, leading to either suppressed or increased fetal mRNA expression of genes related to myogenesis and adipogenesis (Brandão et al., 2020; Shao et al., 2023). The relatively high cost of Ca salts of PUFA (Brandão et al., 2018) may prevent its practical implementation when long periods of supplementation are required (e.g., last 90 d of gestation). Hence, alternative byproducts containing high concentrations of ω-6 PUFA require investigation.

Bakery waste consists of unused bakery products, such as bread, bread rolls, biscuits, cakes, cookies, and dough, that did not meet consumer preferences of freshness or are due to expire. Consequently, their nutrient composition can vary greatly depending on the type and ingredients included (Kaltenegger et al., 2020, 2021). However, bakery waste processing by third party industry (for example, Organic Matters, Inc.; Bartow, FL) prior to delivery at beef cattle operations homogenizes the nutritional composition and value of bakery waste products, making it a feasible feed ingredient for beef cattle. Nutritionally, bakery waste contains less starch and fiber but more sugars and crude fat, mainly from oilseeds rich in ω-6 PUFA (Humer et al., 2018; Kaltenegger et al., 2020, 2021). It was hypothesized that prepartum supplementation of protein and energy from bakery waste containing low or high concentrations of crude fat will enhance maternal circulating concentrations of ω-6 PUFA during gestation and body condition score (BCS) at calving leading to increased offspring postnatal growth and immune function compared to no prepartum supplementation. We further hypothesized that bakery waste containing higher concentrations of ω-6 PUFA will lead to the greatest improvements to calf productive performance during preweaning and preconditioning. Therefore, our objectives were to evaluate the effects of supplementation of bakery waste for late gestating Bos indicus-influenced beef cows on maternal BCS and physiology and offspring postnatal growth and immune response to vaccination.

Materials and Methods

This study was conducted at the University of Florida, Institute of Food and Agricultural Sciences, Range Cattle Research and Education Center (RCREC), Ona, Florida (27°23ʹN and 81°56ʹW) from August 2021 to July 2022. Procedures used in this study were approved by the University of Florida Animal Care and Use Committee (#202111484).

Animals and diets

Prepartum (days 0 to 70) and preweaning (days 70 to 292)

On day 0 of the study (approximately 90 d before calving), 108 multiparous (6 ± 2.5 yr of age), fall-calving, Brangus crossbred cows (~1/4 Bos indicus), pregnant by natural service in the previous breeding season (4 bulls rotated among cows every 28 d), were stratified by body weight (BW; 551 ± 65 kg) and BCS (5.5 ± 0.9) and were randomly allocated into 1 of 18 bahiagrass pastures (6 cows and 4.3 ha per pasture). Maternal treatments were randomly assigned to pastures (6 pastures per maternal treatment) and consisted of no prepartum supplementation (NOSUP) and isocaloric and isonitrogenous supplementation of low-fat (LFAT; 6.4% crude fat) or high-fat (HFAT; 10.7% crude fat) bakery waste byproducts from days 0 to 70 (1 kg of dry matter (DM)per cow per day). The exact ingredient composition of each bakery waste supplement is proprietary (Organic Matters Inc.) but similar ingredients were utilized in different concentrations in both supplements and each supplement type was processed in a single batch, prior to delivery at the research site, to ensure a consistent nutrient profile throughout the study (isocaloric and isonitrogenous but different concentrations of crude fat; Tables 1 and 2). The respective total weekly amount of both supplements was divided into three equal amounts and then offered to cows every Monday, Wednesday, and Friday (2.33 kg of DM per cow per feeding event) at 0800 hours in plastic feed bunks located 1 m above the ground. From days 0 to 292, cows were provided on average 51 g per cow day of a complete salt-based trace mineral and vitamin supplement (16.8% Ca, 4% P, 21% NaCl, 1% Mg, 60 ppm Co, 1,750 ppm Cu, 350 ppm I, 60 ppm Se, 5,000 ppm Zn, 441 IU/g Vitamin A, 33 IU/g Vitamin D₃, and 0.44 IU/g of Vitamin E; University of Florida Cattle Research Winter Mineral; Vigortone, Brookville, OH) by delivering the respective weekly amount of trace mineral and vitamin supplement (51 g/cow × 7 d) once every Monday at 0800 hours.

Table 1.

Average nutritional composition (DM basis) of low fat (LFAT) and high fat (HFAT) bakery waste-based supplements offered to cows from days 0 to 70 and preconditioning concentrate offered to first offspring from days 292 to 345¹

Item2,3	Days 0 to 70		Days 292 to 345
	LFAT	HFAT	Preconditioning concentrate
DM, %	91	91	92
CP, %	13.8	13.7	23.6
Soluble protein, % of CP	23	19	18.0
ADICP, %	0.70	1.10	—
Crude fat, %	6.4	10.7	—
ADF, %	4.6	9.1	32
aNDF, %	9.1	14.8	46
Lignin, %	1.5	2.8	—
NFC, %	68	53	—
Starch, %	44	33	—
ESC (simple sugars), %	10.3	9.1	—
TDN, %4	91	90	73
NEm, Mcal/kg5	2.38	2.33	1.71
NEg, Mcal/kg5	1.65	1.63	1.09
Ash, %	3.71	4.91	—
Ca, %	0.17	0.21	1.51
P, %	0.28	0.36	0.53
Mg, %	0.10	0.14	0.32
K, %	0.31	0.48	1.58
Na, %	0.52	0.49	0.10
S, %	0.18	0.16	0.45
Fe, mg/kg	247	278	274
Zn, mg/kg	24	28	54
Cu, mg/kg	7.0	7.0	9.0
Mn, mg/kg	26	33	22
Mo, mg/kg	0.25	0.33	1.40

¹Treatments consisted of no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture).

²Samples of LFAT and HFAT supplements (Organic Matters Inc.) and preconditioning concentrate were collected every 30 d, composited, and sent in duplicate to a commercial laboratory (Dairy One Forage Laboratory, Ithaca, NY) for wet chemistry analysis.

³As-fed basis: 37.25% soybean hulls, 22% soybean meal, 22% dried distillers’ grains, 15% cottonseed hulls pellets, 2% Ca carbonate, and 1.75% sugarcane molasses (United Feed Company). Trace mineral and vitamin supplement not included in the preconditioning concentrate.

⁴Calculated based on Weiss et al. (1992).

⁵Calculated using equations proposed by NRC (2000).

Table 2.

Fatty acid methyl ester profile (% of total fatty acids) of low fat (LFAT) and high fat (HFAT) bakery waste-based supplements and bahiagrass (Paspalum notatum) pasture provided to cows from days 0 to 70

Item2	Days 0 to 701
	LFAT	HFAT	Forage
Lauric acid (12:0)	0.73	0.80	0.15
Myristic acid (14:0)	0.75	0.89	1.38
Palmitic acid (16:0)	15.1	17.4	22.6
Palmitoleic acid (16:1, ω-7)	0.32	0.31	—
Stearic acid (18:0)	8.57	7.50	3.78
Oleic acid (18:1, ω-9)	30.3	28.3	11.8
Linoleic (18:2, ω-6)	35.1	35.5	15.3
α-Linolenic (18:3, ω-3)	2.85	3.67	19.4
Arachidic acid (20:0)	0.53	0.56	1.72
Gondoic acid (20:1, ω-9)	0.38	0.38	—
Eicosapentaenoic acid (20:5, ω-6)	0.17	0.06	0.22
Behenic acid (22:0)	0.21	0.33	0.62
Docosahexaenoic acid (22:6, ω-3)	0.02	0.06	—
Lignoceric acid (24:0)	0.11	0.15	0.32
Unidentified	4.91	4.05	22.9
Total SFA	25.9	27.6	30.5
Total MUFA	31.0	29.0	11.8
Total PUFA	38.1	39.3	34.9
Total ω-3	2.87	3.73	19.4
Total ω-6	35.3	35.6	15.5

¹Samples of LFAT and HFAT bakery waste-based supplements were collected monthly from days 0 to 70. Pasture samples were collected on days 0, 35, and 70. All samples were pooled across days and sent in duplicate to a commercial laboratory (Dairy One Forage Laboratory, Ithaca, NY) to determine the total and individual concentrations of fatty acid methyl esters (O’Fallon et al., 2007).

²SFA, saturated fatty acids; MUFA, monounsaturated fatty acids; PUFA, polyunsaturated fatty acids; total ω-3 = α-linolenic (18:3) and docosahexaenoic acid (22:6, ω-3); total ω-6 = linoleic (18:2) and eicosapentaenoic acid (20:5).

Cow-calf pairs remained in their respective pasture assignment from day 0 until calf weaning on day 292 (201 ± 17 d of age). Cows were checked twice daily for calving and calved on average on day 89 ± 5 of the study. First offspring (calves in utero when maternal treatments were provided) were weighed (and castrated if male) within the first 12 h of life. From days 110 to 236, all cow–calf pairs received 1) free choice access to limpograss (Hemarthria altissima) hay (in vitro digestible organic matter, IVDOM = 41% of DM; crude protein, CP = 6.5% of DM); and 2) sugarcane (Saccharum officinarum) molasses and urea supplementation (12 kg of DM per week; 75% DM, 76% TDN, and 20% CP; Westway Feed Products LLC, Clewiston, FL), which was divided by 2 and offered every Tuesday and Friday at 0800 hours in open plastic tanks located 1 m above ground to avoid calf consumption of maternal supplements. One Brangus bull (4 ± 2 yr of age) was placed in each pasture on day 140. Bulls were confirmed fertile following breeding soundness exam conducted by a trained veterinarian 90 d before the start of the study. One Brangus bull (4 ± 2 yr of age) was placed in each pasture on day 140 in a manner to ensure similar bull age across treatments, and then rotated among pastures every 28 d from days 140 to 236. No visual signs of injury or difficulty on mounting were detected on all bulls. Percentage of cows pregnant with their second offspring (calves conceived from days 140 to 236) was assessed on day 292 via rectal palpation by a trained veterinarian. Calving percentage of first and second offspring consists of cows that were diagnosed as pregnant (before the start of the study and on day 292) and delivered a live calf at birth. Cows that did not deliver a live calf at birth were not used for blood collections and were removed from the study and all subsequent statistical analyses of any cow data. No calf loss was observed from birth to weaning.

Preconditioning (days 292 to 345)

Immediately after weaning (day 292), 3 heifers per pasture were randomly selected from 15 pastures (5 pastures per maternal treatment) and remained in a single drylot pen for 7 d (days 292 to 299). During this 7-d period, heifers received free choice access to long-stem limpograss hay bales (13.5% CP and 42.8% IVDOM; DM basis) and were gradually adapted to the preconditioning concentrate supplementation (Table 1) by daily increasing the concentrate DM offered from 0.5% to 1.5% of BW (increments of 0.5% of BW every 3 d) in plastic feed bunks at 0800 hours. On day 300, heifers were administered an oral anthelmintic (2.3 mL/45 kg of BW; Safe-Guard; Merck Animal Health, Madison, NJ) and were vaccinated against clostridium (2 mL s.c.; Ultrabac 8, Zoetis) and respiratory pathogens including bovine viral diarrhea virus type 1 (BVDV-1), infectious bovine rhinotracheitis (IBR), parainfluenza-3 (PI₃), bovine respiratory syncytial virus (BRSV), and Mannheimia haemolytica (2 mL s.c.; Bovi Shield Gold One Shot, Zoetis, Parsippany, NJ). Immediately after vaccination, heifers were allocated into 1 of 15 partially covered drylot pens (15 × 5 m and 3 heifers per pen) according to prepartum pasture assignment. From days 300 to 345, heifers were provided free choice access to chopped limpograss hay (3 to 5 cm in length) and concentrate DM supplementation at 1.5% of BW. Hay and concentrate were provided in separate sections in the same concrete feed bunk at 0800 hours. Concentrate consisted of (as-fed basis) 37.25% soybean hulls, 22% soybean meal, 22% dried distillers’ grains, 15% cottonseed hulls pellets, 2% Ca carbonate, and 1.75% sugarcane molasses (United Feed Company, Okeechobee, FL, USA), and its nutritional composition is shown in Table 1. A complete salt-based trace mineral and vitamin supplement (same composition as described above) was hand-mixed daily (51 g/d per heifer) into the high-concentrate diet immediately before every morning feeding. Heifers were revaccinated on day 315 with Bovi Shield Gold 5 (2 mL s.c.; Zoetis) and Ultrabac 8 (2 mL s.c.; Zoetis). The vaccination protocol described herein was selected as our model to elicit an inflammatory response (Moriel et al., 2020; Palmer et al., 2022). Heifers were checked daily from birth until day 345, but no signs of health problems were detected, and no heifer was removed from the study.

Data collection

Forage and feed

Forage samples of all pastures were collected on days 0, 35, and 70 to assess herbage mass and forage nutritive value. Herbage mass was calculated using the double sampling procedure and as described by Gonzalez et al. (1990). Herbage allowance was calculated by dividing the total cow body weight per ­pasture by the respective herbage mass of each pasture (Sollenberger et al., 2005). Limpograss hay samples offered to cows were collected (hand-grabbed) every 28 d from days 110 to 236, and then, composited across all samples to determine the average hay nutritive value (CP and IVDOM). Samples of LFAT and HFAT supplements offered to cows from days 0 to 70 and concentrate and limpograss hay offered to heifers from days 292 to 345 were collected every 28 d, dried at 60 °C in a forced-air oven for 72 h, ground through a 1-mm stainless steel screen (Model 4, Thomas-Wiley Laboratory Mill, Thomas Scientific) before analyses of nutritive value.

Maternal

Individual cow BCS and unshrunk BW were collected once on days 0, 35, 70 (near calving), 140 (start of the breeding season), 195, 236 (end of the breeding season), and 292 (weaning). Cow BCS was performed by two trained technicians (scale 1 to 9), as described by Wagner et al. (1988). Shrunk BW of pregnant cows were not implemented to prevent physiological stress of water and feed removal, which could interfere with calf postnatal performance (Littlejohn et al., 2016). Calving dates of first and second offspring groups were recorded for each cow. Blood samples (10 mL) were collected from jugular vein from the same cows (3 cows per pasture randomly selected on day 0) into sodium-heparin containing tubes (158 USP; Vacutainer, Becton Dickson, Franklin Lakes, NJ) on days 0, 35, 70, and 140 to determine the plasma concentrations of glucose, insulin-like growth factors 1 (IGF-1), and fatty acids. Cows selected for blood sampling were randomly chosen in a manner to represent the average cow BCS, BW, age, and calving date of each respective treatment. Blood samples from cows were placed on ice immediately following collection and were centrifuged at 2,000 × g for 20 min at 4 °C. Plasma samples were stored at −20 °C until further laboratory analysis.

First offspring

Individual unshrunk BW of first offspring was collected within 12 h after birth and on days 140, 195, 236, and 292. Individual shrunk BW of heifers selected for the postweaning phase was collected on days 300 and 345, following 12 h of feed and water withdrawal, to calculate overall average daily gain (ADG) and gain:feed (G:F). Individual full BW of heifers were collected once every 15 d from days 300 to 345 to adjust high-concentrate DM offered. Blood samples (10 mL) were collected from jugular vein into 1) sodium-heparin containing tubes (158 USP; Vacutainer, Becton Dickson) on days 292, 300, 301, 303, 307, and 315 to determine plasma concentrations of cortisol and haptoglobin; and 2) into tubes containing no additive (Vacutainer, Becton Dickson) on days 300, 315, and 345 to assess the serum antibody titers against BVDV-1, IBR, PI₃, and BRSV viruses. Blood samples from first offspring were placed on ice immediately following collection and were centrifuged at 2,000 × g for 20 min at 4 °C. Serum and plasma samples were stored at −20 °C until further laboratory analysis. Daily intake of hay, concentrate, and total (concentrate + hay) were determined daily from days 300 to 345 by subtracting the amount of hay and concentrate of each pen observed at 0800 hours by the respective amount of hay and concentrate offered in the previous day. Samples of hay and concentrate offered and refused during the postweaning period were collected daily from each pen and dried at 60 °C in a forced-air oven for 72 h to determine the respective DM intake of hay and concentrate.

Laboratory analysis

Forage and feed

Forage samples collected from days 0 to 70 were 1) sent to a commercial laboratory (Dairy One Forage Laboratory, Ithaca, NY) to determine the total and individual concentrations of fatty acid methyl esters (Table 2) using gas chromatography (Thermo Trace 1310 Gas Chromatograph fitted with a Supelco SP-2560, 100 m × 0.25 mm × 0.20 µm capillary column; O’Fallon et al. (2007); and 2) sent to the University of Florida Forage Evaluation Support Laboratory (Gainesville, FL) to assess the IVDOM concentration using the two-stage technique (Moore and Mott, 1974) and N concentration using the micro-Kjeldahl technique for N (Gallaher et al., 1975; Table 3). Samples of LFAT and HFAT supplements offered to cows from days 0 to 70 and preconditioning concentrate diet offered to heifers from days 292 to 345 were sent in duplicate to a commercial laboratory (Dairy One Forage Laboratory, Ithaca, NY) for wet chemistry analyses of nutritive value (Table 1). Samples of hay offered from days 292 to 345 were sent in duplicate to the University of Florida Forage Evaluation Support Laboratory to assess IVDOM (Moore and Mott, 1974) and N concentration (Gallaher et al., 1975).

Table 3.

Herbage mass and allowance¹, crude protein (CP), and in vitro digestible organic matter (IVDOM) of bahiagrass (Paspalum notatum) pastures (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)

Item	Maternal treatment2			SEM	P-value	Day of the study			SEM	P-value
	NOSUP	LFAT	HFAT		Maternal treatment	0	35	70		Day of the study
Herbage mass3, kg DM/ha	4,626	4,757	4,636	93.2	0.59	5,280b	5,176b	3,563a	83.0	<0.01
Herbage allowance3, kg DM/kg of BW	5.9	6.0	6.0	0.16	0.89	6.9c	6.5b	4.4a	0.14	<0.01
CP, % of DM	9.4	9.1	9.2	0.17	0.46	10.8c	9.2b	7.7a	0.15	<0.01
IVDOM, %	38.8	38.0	38.7	0.46	0.45	43.5c	38.9b	33.2a	0.47	<0.01

¹Herbage mass calculated using the double sampling technique (Gonzalez et al., 1990). Herbage allowance calculated as the total body weight divided by the respective herbage mass of each pasture (Sollenberger et al., 2005).

²Treatments consisted of no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (August to November).

³Covariate-adjusted for day 0 (P < 0.0001).

^a,b,cWithin a row, means without a common superscript differ (P ≤ 0.05).

Maternal

Plasma concentrations of glucose were determined using commercial colorimetric kits (G7521; Pointe Scientific, Canton, MI). Plasma concentrations of IGF-1 were assessed using a human-specific commercial ELISA kit (SG100; R&D Systems, Inc., Minneapolis, MN) previously validated for bovine IGF-1 (sensitivity of 0.056 ng/mL; Moriel et al., 2012). Intra-assay and inter-assay CV for glucose and IGF-1 were 2.88% and 3.77%, and 3.74% and 4.66%, respectively. Individual and total plasma concentrations of fatty acid methyl esters were assessed using gas chromatography (Agilent 7890, Agilent Technologies, Inc.; Schubach et al., 2019), and only fatty acid methyl esters that were individually identified were reported.

First offspring

Plasma concentrations of cortisol were determined using a single chemiluminescent enzyme assay (Immulite 1000; Siemens Medical Solutions Diagnostics, Los Angeles, CA). Plasma concentrations of haptoglobin were determined using a colorimetric assay (Cooke and Arthington, 2013). Intra-assay CV for cortisol was 4.51%, whereas intra-assay and inter-assay CV for haptoglobin were 3.11% and 2.39%, respectively. Serum neutralization antibody titers were determined by the Oklahoma Animal Disease Diagnostic Laboratory (Stillwater, OK) and reported as the respective log₂ of the greatest dilution that achieved total cell protection (Rosenbaum et al., 1970). Serum neutralization titers that were <4 were considered negative and assigned a value of 0, whereas serum neutralization titers that were ≥4 were considered positive and assigned a value of 1. Positive seroconversion for each virus was calculated as the percentage of heifers with positive serum neutralization titer response (Richeson et al., 2008).

Statistical analysis

All binary data were analyzed using the GLIMMIX procedure of SAS (SAS Institute Inc., Cary, NC, USA, version 9.4). Nonbinary data were analyzed using the MIXED procedure of SAS (version 9.4). Pasture was considered the experimental unit for all statistical analyzes. Forage data, maternal BCS, maternal BW, maternal plasma, cumulative calving distribution of second offspring, first offspring preweaning BW, first offspring preconditioning plasma, and serum data were analyzed as repeated measures and tested for the fixed effects of maternal treatment, day of study, and maternal treatment × day of the study, using pasture(maternal treatment) as random effect. Pasture(maternal treatment) was the subject for the statistical analyses of forage data, whereas either cow(pasture) or heifer(pasture) were included as subjects for their respective statistical analyses. Compound symmetry was used as the covariance structure for all repeated measures as it produced the lowest Akaike information criterion, except for forage data which utilized the autoregressive 1 covariance structure. All forage, and cow data collected on day 0 did not differ among treatments (P ≥ 0.57) but were included in the model as covariate (P < 0.01). Birth BW of the first offspring was covariate adjusted for calf sex and calving date (P = 0.01) but did not differ among maternal treatments (P = 0.26). Maternal BCS and BW change, calving date, first offspring preweaning, and preconditioning ADG, preconditioning DM intake (hay, concentrate, and total), G:F, second offspring birth BW, and calving date of first and second offspring were analyzed for the fixed effects of maternal treatment using pasture(maternal treatment) as random effect. Percentage of cows pregnant with second offspring, percentage of cows calving the first and second offspring, and percentage of male calves at birth were tested for the fixed effects of maternal treatment using pasture(maternal treatment) as random effect. Calf sex and age were included as a covariate for all first and second offspring variables but were removed from the model if P > 0.10. Least-square means were separated using PDIFF function when significance (P ≤ 0.05) was detected. Tendencies were set at 0.05 < P ≥ 0.10.

Results

Precalving (days 0 to 70) and preweaning (days 70 to 292)

Effects of day of the study, but not maternal treatment × day of the study and maternal treatment (P ≥ 0.38), were detected (P < 0.01) for herbage mass and allowance, forage CP and IVDOM. Herbage mass did not differ between days 0 and 35 (P = 0.39) but both days had greater (P < 0.01) herbage mass compared to day 70 (Table 3). Herbage allowance, forage CP and IVDOM were the greatest (P < 0.01) on day 0, intermediate on day 35 (P ≤ 0.03), and lowest on day 70 (P < 0.01; Table 3).

Maternal treatment × day of the study effects were observed (P < 0.01) for cow BCS and BW (Table 4). Cow BCS on days 35, 70, and 195 were the least (P ≤ 0.05) for NOSUP cows and did not differ (P ≥ 0.12) between LFAT and HFAT cows. Cow BCS on day 140 was greater (P = 0.05) for HFAT vs. NOSUP cows and intermediate (P ≥ 0.35) for LFAT cows. Cow BCS on day 236 did not differ (P ≥ 0.12) among maternal treatments, whereas cow BCS on day 292 tended to be greater (P = 0.06) for HFAT vs. NOSUP cows and was intermediate (P ≥ 0.27) for LFAT cows. Effects of maternal treatment were detected (P < 0.01) for cows BCS change from days 0 to 70 and days 70 to 140, but not (P ≥ 0.31) for BCS change from days 140 to 236 and days 236 to 292 (Table 4). Cow BCS change from days 0 to 70 did not differ (P = 0.38) between LFAT and HFAT cows and was the least (P ≤ 0.02) for NOSUP cows. Cow BCS change from days 70 to 140 did not differ (P = 0.20) between NOSUP and HFAT cows and was the least (P ≤ 0.04) for LFAT cows. Cow BW on days 35, 195, 236, and 292 did not differ (P ≥ 0.12) among maternal treatments. Cow BW on day 70 was greater (P = 0.03) for LFAT vs. NOSUP cows and intermediate (P ≥ 0.82) for HFAT cows, whereas cow BW on day 140 tended to be the least (P ≤ 0.07) for NOSUP cows and did not differ (P = 0.93) between LFAT and HFAT cows. Cow BW change from days 0 to 70, 70 to 140, and 236 to 292 did not differ (P ≥ 0.18) among maternal treatments. Cow BW change from days 140 to 236 did not differ (P = 0.83) between LFAT and HFAT cows and was the least (P ≤ 0.05) for NOSUP cows (Table 4).

Table 4.

Body condition score (BCS) and body weight (BW) of cows offered no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)

Item	Maternal treatment1			SEM	P-value
	NOSUP	LFAT	HFAT		Maternal treatment	Maternal treatment × day
Cow BCS2
Day 0	5.48a	5.43a	5.44a	0.131	0.06	<0.01
Day 35	5.57a	5.88b	5.90b	0.131
Day 70 (near calving)	5.43a	6.16b	5.97b	0.131
Day 140 (start of breeding season)	5.02a	5.15ab	5.33b	0.131
Day 195	4.84a	5.16b	5.46b	0.131
Day 236 (end of breeding season)	4.94a	5.22a	5.14a	0.131
Day 292 (weaning)	5.17x	5.37xy	5.50y	0.131
Cow BCS change
Days 0 to 702	−0.02a	0.71b	0.52b	0.151	<0.01	—
Days 70 to 140	−0.42a	−0.99b	−0.63a	0.128	<0.01	—
Days 140 to 2362	−0.02	0.03	−0.15	0.133	0.60	—
Days 236 to 292	0.22	0.16	0.37	0.103	0.31	—
Cow BW3, kg
Day 0	553a	549a	549a	6.1	0.62	0.02
Day 35	583a	582a	580a	6.1
Day 70 (near calving)	587a	608b	589ab	6.1
Day 140 (start of breeding season)	525x	540y	540y	6.1
Day 195	509a	516a	522a	6.1
Day 236 (end of breeding season)	515a	515a	515a	6.1
Day 292 (weaning)	553a	559a	550a	6.1
Cow BW change, kg
Days 0 to 703	38	57	38	8.3	0.18	—
Days 70 to 140	−63	−68	−50	8.8	0.35	—
Days 140 to 236	−9b	−26a	−25a	5.8	0.05	—
Days 236 to 292	38	44	38	4.9	0.59	—

¹Weekly amount of LFAT and HFAT supplements was divided into three equal amounts and offered every Monday, Wednesday, and Friday. Cows calved their first offspring on average on day 89 ± 5. All pastures were offered free choice access to limpograss hay and supplemented with sugarcane molasses + urea (12 kg DM per cow per week) from days 110 to 236.

²Covariate-adjusted for cow BCS on day 0 (P ≤ 0.008).

³Covariate-adjusted for cow BW on day 0 (P < 0.0001).

^a,bWithin a row, means without common superscript differ (P ≤ 0.05).

^x,yWithin a row, means without common superscript tended to differ (0.05 > P ≤ 0.10).

Effects of maternal treatment × day of the study and maternal treatment were not detected (P ≥ 0.12) for plasma concentrations of glucose (on average 78.1, 74.1, and 75.8 ± 1.44 mg/dL for NOSUP, LFAT, and HFAT cows, respectively) and IGF-1 (on average 39.2, 43.3, and 41.8 ± 2.40 ng/mL for NOSUP, LFAT, and HFAT cows, respectively). Effects of maternal treatment × day of the study were detected (P ≤ 0.01) for plasma concentrations of stearic acid, linoleic acid, total SFA, total PUFA, total ω-6 fatty acids, and total fatty acids identified (Table 5). Effects of maternal treatment were detected (P ≤ 0.04) for plasma concentrations of pentadecanoic acid, palmitic acid, arachidonic acid, osbond acid, and docosapentaenoic acid (Table 6). Effects of day of the study, but not maternal treatment × day of the study and maternal treatment (P ≥ 0.17), were detected (P < 0.01) for plasma ­concentrations of tridecanoic acid, palmitoleic acid, heptadecanoic acid, oleic acid, α-linolenic acid, γ-linolenic acid, arachidic acid, gondoic acid, dihomo-γ-linolenic acid, docosadienoic acid, docosatrienoic acid, total MUFA, and total ω-3 fatty acids (Table 6). Effects of maternal treatment × day of the study, maternal treatment, and day of the study were not detected (P ≥ 0.18) for plasma concentrations of docosahexaenoic acid and lignoceric acid (Table 6).

Table 5.

Plasma concentrations of fatty acid methyl esters (µg/mL) on days 0, 35, 70, and 140 of cows offered no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)¹

Item2,3	Day of the study				SEM	P-value
	0	35	70	140		Maternal treatment × day of the study
Stearic acid (18:0)
NOSUP	89a	94a	93a	86a	1.8	<0.01
LFAT	84a	94a	95a	89a	1.8
HFAT	86a	93a	92a	96b	1.8
Linoleic acid (18:2, ω-6)
NOSUP	184a	185a	200a	183a	7.6	<0.01
LFAT	183a	197a	222b	190a	7.6
HFAT	189a	198a	218b	247b	7.6
Total SFA
NOSUP	196a	203a	203a	191a	3.2	0.01
LFAT	188a	202a	207a	197a	3.2
HFAT	192a	203a	208a	210b	3.2
Total PUFA
NOSUP	206a	209a	230a	211a	7.6	<0.01
LFAT	204a	220a	249b	219a	7.6
HFAT	214a	222a	246b	277b	7.6
Total ω-6
NOSUP	191a	193a	209a	190a	7.4	<0.01
LFAT	195a	204a	230b	198a	7.4
HFAT	197a	206a	226b	256b	7.4
Total identified
NOSUP	431a	449a	469a	435a	9.4	<0.01
LFAT	420a	459a	492b	451a	9.4
HFAT	435a	461a	492b	525b	9.4

¹Cows calved their first offspring on average on day 89 ± 5. All pastures were offered free choice access to limpograss hay and supplemented with sugarcane molasses + urea (12 kg DM per cow per week) from days 110 to 236.

³SFA, saturated fatty acids; PUFA, polyunsaturated fatty acids; total ω-6 = linoleic (18:2), γ-linolenic (18:3), dihomo-γ-linolenic (20:3), arachidonic (20:4), docosadienoic (22:2), and osbond (22:5) acids.

²Plasma concentrations on day 0 of all fatty acids did not differ (P ≥ 0.23) among treatments but were covariate-adjusted for the respective plasma concentrations on day 0 (P ≤ 0.05).

^a,bWithin day of the study, means without common superscript differ (P ≤ 0.05).

Table 6.

Average plasma concentrations of fatty acid methyl esters (µg/mL) of cows offered no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)

Item1,2	Maternal treatment			SEM	P-value3
	NOSUP	LFAT	HFAT		Maternal treatment	Maternal treatment × day of the study
Tridecanoic acid (13:0)	0.26	0.29	0.25	0.041	0.77	0.75
Myristic acid (14:0)	2.26	2.11	2.21	0.085	0.44	0.11
Pentadecanoic acid (15:0)	1.98b	1.75a	1.77a	0.084	0.03	0.12
Palmitic acid (16:0)	104a	104a	108b	0.9	<0.01	0.21
Palmitoleic acid (16:1, ω-7)	3.16	3.20	3.14	0.198	0.98	0.85
Heptadecanoic acid (17:0)	2.93	2.76	2.94	0.135	0.59	0.86
Stearic acid (18:0)	90	91	92	1.2	0.68	<0.01
Oleic acid (18:1, ω-9)	24.8	25.2	26.5	1.21	0.56	0.90
Linoleic acid (18:2, ω-6)	188	198	213	3.7	<0.01	<0.01
α-Linolenic acid (18:3, ω-3)	14.4	13.9	13.5	0.71	0.68	0.27
γ-Linolenic acid (18:3, ω-6)	0.57	0.58	0.51	0.078	0.77	0.59
Arachidic acid (20:0)	0.64	0.61	0.62	0.044	0.92	0.37
Gondoic acid (20:1, ω-9)	0.61	0.79	0.69	0.065	0.19	0.71
Dihomo-γ-linolenic acid (20:3, ω-6)	1.86	1.76	2.03	0.100	0.17	0.23
Arachidonic acid (20:4, ω-6)	3.09a	2.98a	3.50b	0.152	0.04	0.97
Docosadienoic acid (22:2, ω-6)	1.65	1.43	1.49	0.111	0.37	0.49
Docosatrienoic acid (22:3, ω-3)	1.86	1.78	2.08	0.158	0.40	0.25
Osbond acid (22:5, ω-6)	0.39a	0.38a	0.53b	0.033	<0.01	0.15
Docosapentaenoic acid (22:5, ω-3)	0.35a	0.42a	1.17b	0.132	<0.01	0.35
Docosahexaenoic acid (22:6, ω-3)	1.69	1.73	1.76	0.087	0.86	0.90
Lignoceric acid (24:0)	0.78	0.77	0.81	0.034	0.62	0.22
Total SFA	198	198	203	1.9	0.12	0.01
Total MUFA	28.0	28.4	39.7	1.35	0.66	0.94
Total PUFA	214	223	240	3.6	<0.01	<0.01
Total ω-3	18.3	17.8	18.5	0.88	0.86	0.48
Total ω-6	196	207	221	3.6	<0.01	<0.01
Total identified	446	456	478	4.6	<0.01	<0.01

¹Plasma samples of cows were collected on days 0, 35, 70, and 140. All plasma fatty acid concentrations on day 0 did not differ (P ≥ 0.23) among maternal treatments but were covariate-adjusted for the respective plasma concentrations on day 0 (P ≤ 0.05).

²SFA, saturated fatty acids; MUFA, monounsaturated fatty acids; PUFA, polyunsaturated fatty acids.

³Effects of day of the study were detected (P ≤ 0.02) for all plasma fatty acids, except (P ≥ 0.16) for γ-linolenic, gondoic, dihomo-γ-linolenic, osbond, docosapentaenoic, docohexaenoic, and lignoceric acids.

^a,bWithin a row, means without common superscript differ (P ≤ 0.05).

Calving percentage, percentage of male calves, and calving date of the first offspring did not differ (P ≥ 0.34; Table 7) among maternal treatments. Percentage of pregnant cows, calving percentage, percentage of male calves, and birth BW of the second offspring did not differ (P ≥ 0.13; Table 7) among maternal treatments. Calving date tended (P = 0.06) to differ among maternal treatments and was greater (P = 0.01) for NOSUP vs. HFAT cows, whereas LFAT cows were intermediate (P ≥ 0.18; Table 7). Effects of maternal treatment × day of the study were detected for cumulative calving distribution of the second offspring (Table 7). A greater percentage of HFAT cows calved (P ≤ 0.05) from days 429 to 450 compared to NOSUP and LFAT cows and from days 451 to 471 compared to LFAT cows. Calving distribution from days 472 to 492 did not differ (P ≥ 0.42) among maternal treatments.

Table 7.

Reproductive performance of cows offered no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)

Item2	Maternal treatment1			SEM	P-value3
	NOSUP	LFAT	HFAT
First offspring
Calving4, % of total pregnant cows	93.8	86.1	86.1	5.19	0.41
Calving date, day of the study	89	90	84	3.1	0.34
Male calves at birth, %	47.8	56.7	58.6	9.35	0.61
Calf birth BW5, kg	35.5	36.7	35.0	0.77	0.26
Second offspring
Pregnant day 292, % of total cows	97.9	94.1	100.0	2.73	0.30
Calving4, % of total pregnant cows	87.2	80.0	86.0	6.17	0.65
Calving date, day of the study	456b	451ab	446a	2.9	0.06
Calving distribution, %
Day 429 to 450 (first 21 d of calving season)	68.1a	70.8a	85.7b	5.64	0.03
Day 451 to 471 (second 21 d of calving season)	90.7ab	80.7a	100.0b	5.64
Day 472 to 492 (third 21 d of calving season)	99.9a	93.5a	100.0a	5.64
Male calves at birth, %	60.5	45.2	70.4	9.25	0.13
Calf birth BW, kg	36.0	34.1	35.4	0.98	0.29

¹Weekly amount of LFAT and HFAT supplements was divided into three equal amounts and offered every Monday, Wednesday, and Friday from days 0 to 70.

²First offspring comprises of calves that were in utero when maternal treatments were provided (days 0 to 70). Second offspring comprises of calves that were conceived during the breeding season (days 140 to 236).

³ P-value for the effects of maternal treatment × day of the study for calving distribution or P-value for the overall effects of maternal treatment for all remaining variables.

⁴Calving percentage consists of cows that were diagnosed as pregnant and delivered a live calf at birth. Cows that did not deliver a live calf at birth were not used for blood collections and were removed from the study and all subsequent statistical analyses of any cow data.

⁵Covariate-adjusted for calf sex and calving date (P ≤ 0.01).

^a,bWithin a row, means without common superscript differ (P ≤ 0.05).

Effects of maternal treatment × day of the study were detected (P < 0.01) for preweaning BW of first offspring (Table 8). First offspring BW on day 140 did not differ among treatments. First offspring BW on days 195 and 236 were greater (P ≤ 0.05) for LFAT vs. NOSUP calves and were intermediate for HFAT calves (P ≥ 0.31). First offspring BW on day 292 were the greatest (P ≤ 0.05) for LFAT calves, ­intermediate for HFAT calves, and least for NOSUP calves. First offspring ADG from birth to weaning was greater (P = 0.02) for LFAT vs. NOSUP calves and were intermediate for HFAT calves (P ≥ 0.11).

Table 8.

Preweaning body weight of first offspring born to cows offered no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)

Item	Maternal treatment1			SEM	P-value
	NOSUP	LFAT	HFAT		Maternal treatment	Maternal treatment × day of the study
First offspring BW2, kg
Day 140 (start of breeding season)	86a	92a	89a	3.5	0.04	<0.01
Day 195	127a	136b	131ab	3.5
Day 236 (end of breeding season)	163a	175b	168ab	3.5
Day 292 (weaning)	227a	244c	234b	3.5
ADG birth to weaning3, kg/d	0.94a	1.01b	0.96ab	0.024	0.05	—

¹Cows calved their first offspring on average on day 89 ± 5. All pastures were offered free choice access to limpograss hay and supplemented with sugarcane molasses + urea (12 kg DM per cow per week) from days 110 to 236 and remained on their respective pasture until day 292.

²Covariate-adjusted for calf age (P < 0.01).

³Covariate-adjusted for calf sex and age (P ≤ 0.02).

^a,bWithin a row, means without common superscript differ (P ≤ 0.05).

Preconditioning (days 292 to 344)

Preconditioning BW of first offspring was the least (P ≤ 0.05) for NOSUP heifers and did not differ (P ≥ 0.16) between LFAT and HFAT heifers on days 300 and 345 (Table 9). Effects of maternal treatment were not detected (P ≥ 0.11) for preconditioning ADG, G:F, and DM intake of concentrate, hay, and total (concentrate + hay; Table 9).

Table 9.

Growth and intake during preconditioning (days 300 to 345) of first offspring¹ born to cows offered no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)

Item	Maternal treatment1			SEM	P-value
	NOSUP	LFAT	HFAT		Maternal treatment
BW day 300 (drylot entry), kg	201a	232b	218b	6.9	<0.01
BW day 345 (drylot exit), kg	235a	266b	255b	6.9	<0.01
ADG, kg/d	0.79	0.78	0.84	0.049	0.52
Concentrate DM intake2, % of BW	1.46	1.48	1.47	0.007	0.35
Hay DM intake2, % of BW	1.00	0.99	0.87	0.051	0.27
Total DM intake2, % of BW	2.46	2.40	2.35	0.051	0.33
G:F3	0.15	0.13	0.15	0.006	0.11

¹On day 292 (weaning), 3 heifers per pasture were randomly selected from 5 pastures per maternal treatment and remained in a single drylot pen for 7 d. Then, heifers were assigned to 15 drylot pens (3 heifers per pen using same maternal pasture distribution) until day 345. Heifers were provided free choice access to limpograss hay and concentrate DM supplementation at 1.5% of BW from days 292 to 300.

²Calculated by dividing the average daily DM intake of concentrate, hay, or total (concentrate + hay) by average shrunk BW of each pen from days 300 to 345.

³Calculated by dividing total BW gain by total DM intake from days 300 to 345.

^a,bWithin a row, means without common superscript differ (P ≤ 0.05).

Effects of maternal treatment, but not maternal treatment × day (P = 0.38), tended to be detected (P = 0.10) for plasma concentrations of cortisol of the first offspring, which were greater (P = 0.03) for NOSUP vs. HFAT heifers and intermediate for LFAT heifers (P ≥ 0.26; Table 10). Effects of maternal treatment × day and maternal treatment were not detected (P ≥ 0.56) for plasma concentrations of haptoglobin of the first offspring (Table 10). Effects of day were detected (P < 0.01) for plasma concentrations of cortisol (1.71, 2.04, 2.03, 1.93, 2.22, 3.24 ± 0.17 µg/dL on days 292, 300, 301, 303, 307, and 315, respectively) and haptoglobin (0.32, 0.30, 1.31, 1.67, 0.50, and 0.50 ± 0.07 mg/mL on days 292, 300, 301, 303, 307, and 315, respectively). Plasma haptoglobin concentrations peaked on day 301 and remained above baseline levels until day 315.

Table 10.

Plasma and serum data during preconditioning (days 300 to 345) of first offspring¹ born to cows offered no prepartum supplementation (NOSUP) and 1 kg/d of low-fat (LFAT) or high-fat (HFAT) bakery waste-based supplement from days 0 to 70 (6 pastures per maternal treatment; 6 cows and 4.3 ha per pasture)

Item2,3	Maternal treatment1			SEM	P-value
	NOSUP	LFAT	HFAT		Maternal treatment	Maternal treatment × day of the study
Plasma cortisol, µg/dL	2.50b	2.20ab	1.91a	0.201	0.10	0.38
Plasma haptoglobin, mg/mL	0.79	0.81	0.71	0.064	0.56	0.63
Serum BVDV-1
Titers, log2	7.38	8.11	7.97	0.508	0.51	0.74
Seroconversion, % total	97.8	100	97.2	2.07	0.61	0.30
Serum IBR
Titers, log2
Day 292 (weaning)	0.47a	1.00a	0.33a	0.489	0.12	<0.01
Day 315 (first vaccination)	4.80b	3.68a	5.50b	0.489
Day 345 (end of preconditioning)	5.20ab	4.22a	5.83b	0.489
Seroconversion, % total
Day 292 (weaning)	20.0a	38.5b	8.3a	8.11	0.02	0.08
Day 315 (first vaccination)	100a	100a	100a	8.11
Day 345 (end of preconditioning)	100a	100a	100a	8.11
Serum PI3
Titers, log2	4.60	3.99	4.33	0.488	0.64	0.77
Seroconversion, % total
Day 292 (weaning)	66.7a	61.5a	50.0a	11.3	0.56	0.08
Day 315 (first vaccination)	60.0a	69.2a	100b	11.3
Day 345 (end of preconditioning)	93.3a	100a	100a	11.3
Serum BRSV
Titers, log2
Day 292 (weaning)	1.80xy	2.31x	0.92y	0.569	0.96	0.09
Day 315 (first vaccination)	3.87a	3.62a	4.33a	0.569
Day 345 (end of preconditioning)	5.40xy	5.11x	6.25y	0.569
Seroconversion, % total
Day 292 (weaning)	80.0b	84.6b	41.7a	7.29	0.03	0.01
Day 315 (first vaccination)	100a	100a	100a	7.29
Day 345 (end of preconditioning)	100a	100a	100a	7.29

¹On day 292 (weaning), 3 heifers per pasture were randomly selected from 5 pastures per maternal treatment.

²Heifers received an oral anthelmintic (Merck Animal Health) and were vaccinated with Bovi Shield Gold One Shot and Ultrabac 8 (Zoetis) on day 300 and revaccinated with Bovi Shield Gold 5 and Ultrabac 8 on day 315.

³Serum titers reported as log₂ of the greatest dilution of serum that provided complete cell protection. Heifers were considered seropositive if they had serum neutralization values ≥ 4.

^a,bWithin a row, means without common superscript differ (P ≤ 0.05).

Effects of maternal treatment × day of the study and maternal treatment were not detected (P ≥ 0.51) for serum titers against BVDV-1 and PI₃ viruses but were detected (P < 0.01) for serum titers against IBR virus and tended (P = 0.09) to be detected for serum titers against BRSV (Table 10). Serum IBR titers on day 315 were the least (P ≤ 0.03) for LFAT heifers and did not differ (P = 0.29) between NOSUP vs. HFAT heifers, whereas serum IBR titers on day 345 were greater (P = 0.05) for HFAT vs. LFAT heifers and were intermediate (P = 0.45) for NOSUP heifers. Serum BRSV titers on days 292 and 345 tended (P = 0.08) to be greater for LFAT vs. HFAT heifers and intermediate (P ≥ 0.27) for NOSUP heifers, whereas serum BRSV titers on day 315 did not differ (P ≥ 0.33) among treatments. Effects of maternal treatment × day of the study were detected (P = 0.01) for seroconversion against BRSV and tended (P = 0.08) to be detected for seroconversion against PI₃ and IBR viruses, but not (P = 0.30) for seroconversion against BVDV-1 virus (Table 10). Seroconversion against BRSV was the least (P < 0.01) for HFAT heifers and did not (P = 0.63) differ between NOSUP and LFAT heifers on day 292 and did not differ (P ≥ 0.99) among treatments on days 315 and 345. Seroconversion against IBR virus did not differ (P ≥ 0.32) among treatments on day 292, was greater for NOSUP and HFAT vs. LFAT heifers (P < 0.01) on day 315, and was greater for HFAT vs. LFAT heifers and intermediate for NOSUP heifers on day 345 (Table 10). Seroconversion against PI₃ virus did not differ (P ≥ 0.27) among treatments on days 292 and 345 and was greater (P ≤ 0.05) for HFAT vs. NOSUP and LFAT heifers on day 315 (Table 10).

Discussion

Maternal performance

Herbage allowance from days 0 to 70 was always 3 to 5 times greater than the minimum herbage allowance (1.40 kg DM/kg BW) required for ad libitum intake of bahiagrass pastures without concentrate supplementation (Inyang et al., 2010). Supplemental DM intake of LFAT and HFAT cows was on average 0.17% of BW from days 0 to 70 and did not impact herbage mass, herbage allowance, and forage concentrations of IVDOM and CP. These results agree with our previous studies (Moriel et al., 2020; Palmer et al., 2020, 2022; Izquierdo et al., 2022; Vedovatto et al., 2022) and indicate that providing supplemental protein and energy at <0.20% of BW during the third trimester of gestation likely did not impact forage DM intake, leading to no effects on herbage mass. In support of this rationale, supplemental fat intake of LFAT and HFAT cows was on average 0.44% and 0.75% of their estimated total DM intake (NASEM, 2016), which is below the supplemental fat intake limit (2% of total DM intake) required to prevent reductions in forage DM intake (Hess et al., 2008).

In agreement with previous studies conducted in the same location and with similar cattle breed and category (Palmer et al., 2020, 2022; Izquierdo et al., 2022; Vedovatto et al., 2022), supplemental protein and energy provided by LFAT and HFAT supplements increased maternal BCS near calving compared to NOSUP cows. Despite the similar postpartum management, BCS loss from calving until the start of the breeding season was greater for LFAT vs. HFAT and NOSUP cows and did not differ among treatments from the start of the breeding season until calf weaning. Hence, maternal treatment-induced differences observed for cow BCS near calving remained until calf weaning. These results were previously reported and reinforce the positive effects of maternal protein and energy supplementation for fall-calving, late-gestating beef cows grazing warm-season grasses (Moriel et al., 2020; Palmer et al., 2020, 2022; Izquierdo et al., 2022; Vedovatto et al., 2022). Maternal supplementation of isocaloric and isonitrogenous supplements containing different profiles of fatty acids during late gestation did not impact maternal pre- and postpartum BCS (Marques et al., 2017; Brandão et al., 2020; Shao et al., 2021a, 2023). Likewise, cow BCS throughout the study did not differ between LFAT and HFAT cows, which was expected as prepartum supplement DM amount (1 kg DM per cow per day) was the same between both treatments and supplemental fatty acid intake from both supplements was below 2% of total DM intake (Hess et al., 2008). Therefore, differences in forage DM intake and total nutrient intake likely did not occur between LFAT and HFAT cows.

Forage samples collected from days 0 to 70 contained on average 1.13% total fatty acids (DM basis) with palmitic, oleic, linoleic, and α-linolenic representing >69% of total fatty concentrations. By design, LFAT and HFAF had different total concentrations of crude fat, but the profile of fatty acids was similar between both supplements with palmitic, oleic, and linoleic acids representing most of all fatty acids. Plasma concentrations of fatty acids are directly proportional to the absolute amount of fatty acids being absorbed from the small intestine (Noble et al., 1972). Plasma concentrations of linoleic acid, total PUFA, total ω-6, and total fatty acids near calving increased for HFAT and LFAT vs. NOSUP cows and did not differ between HFAT and LFAT cows. However, plasma concentrations of linoleic acid, total PUFA, total ω-6, and total fatty acids identified on day 35 did not differ among treatments, suggesting that perhaps fetal supply of those fatty acids on day 35 were potentially similar among treatments or fatty acids were removed from maternal blood and incorporated into maternal and fetal tissues in larger extent during initial maternal supplementation period (Garcia et al., 2014). These responses to plasma fatty acids observed herein may also be attributed to the relatively small amount of supplemental fat delivered by LFAT and HFAT supplements and the lack of protection against rumen biohydrogenation, which combined may have required longer periods of supplementation to achieve a net increase in maternal circulating concentrations of targeted fatty acids. In agreement, Shao et al. (2023) observed that the relative plasma concentrations of linoleic acid of fall-calving cows fed 150 to 160 g/d of supplemental fat from Ca salts of SFA/MUFA or PUFA during late gestation did not differ from each other, but both were greater compared to cohorts offered no fat supplementation after 42 and 84 d of maternal supplementation during late gestation. Moreover, Shao et al. (2021a) did not detect differences in plasma concentrations of linoleic acid after fall-calving cows were supplemented with Ca salts of SFA/MUFA or PUFA for 42 and 84 d during late gestation. In contrast, Marques et al. (2017) and Brandão et al. (2020) observed greater plasma concentrations of linoleic acid, total PUFA, and total ω-6 at calving in spring-calving beef cows fed 190 g/d of a combination of Ca salts of ω-3 and ω-6 (Marques et al., 2017) or 195 g/d of Ca salts of ω-6 (Brandão et al., 2020) during late gestation compared to supplementation of Ca salts of SFA/MUFA. The inconsistency among our results and those reported by others (Marques et al., 2017; Brandão et al., 2020; Shao et al., 2021a, 2023) is likely due to differences in fat source (bakery waste vs. Ca salts of fatty acids) and degree of protection against rumen biohydrogenation (Moallem et al., 2018), supplemental fat amount (64 to 107 vs. 150 to 195 g/d), cow subspecies (Bos indicus-influenced vs. Bos taurus), total concentration and profile of fatty acids in the forage, and perhaps calving season (fall vs. spring) and additional unknown factors.

One unexpected outcome was that plasma concentrations of stearic, linoleic, total SFA, total PUFA, total ω-6, and total fatty acids remained greater for HFAT vs. LFAT and NOSUP cows until the start of the breeding season (70 d after maternal treatment supplementation was ceased). Previous studies evaluating the effects of maternal prepartum supplementation of fatty acids on cow–calf performance (Banta et al., 2006, 2011; Marques et al., 2017; Brandão et al., 2020; Shao et al., 2021a, 2023) did not evaluate maternal plasma concentrations of fatty acids beyond the treatment supplementation period, so a direct comparison with our results was not possible. Nonetheless, Schubach et al. (2019) supplemented beef steers with 150 g/d of Ca salts of SFA or ω-6 fatty acids during 40 d of preconditioning and then assigned all steers to growing and finishing periods in the feedlot. Steers fed Ca salts of ω-6 fatty acids had greater plasma concentrations of linoleic, total ω-6, total PUFA, and total fatty acids compared to steers fed Ca salts of SFA at the end of the preconditioning period, but no differences in plasma concentrations of those fatty acids were detected between treatments during finishing (157 d after treatment supplementation ceased). Reasons for the long-term sustained greater plasma concentrations of stearic, linoleic, total SFA, total PUFA, total ω-6, and total fatty acids in HFAT vs. LFAT and NOSUP cows remain unknown and deserve further investigation.

Average plasma concentrations of palmitic, arachidonic, osbond, and docosapentaenoic acids were slightly greater for HFAT cows and did not differ between LFAT and NOSUP cows. Greater concentrations of palmitoleic acid in HFAT cows likely reflect the increased supplemental intake and de novo synthesis of palmitoleic acid (Loften et al., 2014) compared to NOSUP and LFAT cows. Likewise, pregnant beef cows offered PUFA supplementation had increased plasma concentrations of palmitoleic acid at calving compared to those offered SFA/MUFA supplementation (Shao et al., 2023). Arachidonic, osbond, and docosapentaenoic acids were not detected in the samples of pasture and LFAT and HFAT ­supplements. Although linoleic acid may serve as a precursor for the synthesis of arachidonic acid (Staples et al., 1998) and eicosapentaenoic can be converted into docosapentaenoic acid (and vice-versa) in the liver (Kaur et al., 2011; Moallem et al., 2018), average plasma concentrations of arachidonic, osbond, and docosapentaenoic acids detected herein were 5- to 54-fold lower compared to those reported by Brandão et al. (2020) and likely had limited biological importance in the present study. Overall, maternal plasma concentrations of linoleic, PUFA, and total ω-6, which are known for impacting postnatal offspring performance (Cappellozza et al., 2021), were successfully increased following 70 d of maternal prepartum supplementation of LFAT and HFAT bakery waste.

In utero availability of glucose and amino acids modulates fetal growth (Bauer et al., 1998; Bell, 1995). Glucose supply to the fetus is regulated by maternal circulating concentrations of glucose (Baumann et al., 2002), whereas circulating IGF-1 is synthesized and regulated by the placenta and maternal and fetal tissues (Gicquel and Le Bouc, 2006). Plasma concentrations of both glucose and IGF-1 typically increase with greater energy and protein consumption (Cappellozza et al., 2014). However, maternal supplementation of protein and energy led to inconsistent impacts on maternal circulating concentrations of glucose and IGF-1 during late pregnancy. For instance, maternal supplementation of protein and energy during late gestation increased maternal plasma concentrations of both glucose and IGF-1 (Izquierdo et al., 2022), only glucose (Palmer et al, 2020), or only IGF-1 (Moriel et al., 2020; Palmer et al., 2022; Vedovatto et al., 2022). Maternal supplementation of LFAT and HFAF treatments did not impact prepartum plasma concentrations of glucose and IGF-1 compared to NOSUP cows. However, circulating concentrations of glucose and IGF-1 are the end results of a dynamic process involving timing of blood collection relative to peak release of hormones and metabolites, amount of supplemental protein and energy, animal category, and nutrient uptake and hormonal synthesis by maternal and fetal tissues. Furthermore, LFAT and HFAT supplements utilized herein contained CP concentrations that were lower compared to those previously reported (13% vs. >20% of DM, respectively; Moriel et al., 2020; Palmer et al., 2020, 2022; Izquierdo et al., 2022; Vedovatto et al., 2022). Plasma concentrations of IGF-1 increased linearly with increasing CP intake when total metabolizable energy consumed was above 17 Mcal (Elsasser et al., 1989) but not when total metabolizable energy consumed was below 11 Mcal (Elsasser et al., 1989; Moriel and Arthington, 2013). Previous studies evaluating the effects of maternal supplementation of different profiles of fatty acids during late gestation did not evaluate maternal circulating concentrations of glucose and IGF-1 (Banta et al., 2006, 2011; Marques et al., 2017; Brandão et al., 2020; Shao et al., 2021a, 2023), so data comparison with our results was not possible. Nonetheless, the lack of differences for plasma concentrations of glucose and IGF-1 between LFAT and HFAT cows can be attributed to their isocaloric and isonitrogenous profiles and supplemental fatty acids intake below 2% of total DM intake (Hess et al., 2008; Moriel et al., 2011).

The present study was designed primarily to evaluate cow and calf physiological and growth responses and was not adequately powered to evaluate binary responses associated with pregnancy attainment. Nonetheless, maternal supplementation of protein and energy during late gestation: (1) improved pregnancy percentage when cows calved at BCS < 4.75 (Vedovatto et al., 2022) but not when cows calved at BCS > 4.75 (Moriel et al., 2020; Palmer et al., 2020, 2022; Izquierdo et al., 2022); and (2) resulted in earlier calving (Palmer et al., 2020, 2022). Maternal prepartum supplementation of fat had no effects on postpartum reproductive success (Banta et al., 2011; Shao et al., 2021a, 2023) or increased first service conception rate (Banta et al., 2006) and overall pregnancy rate (Bellows et al., 2001) compared to no fat supplementation. In the present study, maternal supplementation of HFAT and LFAT bakery waste did not increase final pregnancy percentage compared to NOSUP, which may be attributed to NOSUP cows calving and starting the breeding season with BCS > 5. However, the percentage of cows calving their second offspring during the first 21 d of the calving season increased for HFAT vs. NOSUP and LFAT cows. A relatively high supply of linoleic acid can inhibit the production of PGF_2α leading to improved reproductive success (Thatcher et al., 1997; Staples et al., 1998). The greater postpartum BCS and plasma concentrations of total PUFA, linoleic and arachidonic acids of HFAT cows at the start of the breeding season may have contributed to their improved early pregnancy attainment.

Offspring performance

Preweaning

In the present study, first offspring BW at birth was not impacted by maternal supplementation of HFAT and LFAT bakery waste compared to no prepartum supplementation. Maternal supplementation of protein and energy during gestation (first, second, or third trimester of gestation depending on the study) had either no effects or increased offspring birth BW by on average 3.2 kg (Moriel et al., 2021). Subsequent studies at the same research site as herein also observed that offspring birth BW was not impacted (Palmer et al., 2022) or increased by 2.9 kg (Izquierdo et al., 2022; Vedovatto et al., 2022) following maternal prepartum supplementation of protein and energy from low-fat ingredients (DDG or sugarcane molasses + urea; total crude fat < 1.7% of DM). Impacts of maternal prepartum supplementation of different fat sources (e.g., oilseeds and Ca salts of ω-3 and ω-6 fatty acids) led to more consistent outcomes to offspring birth BW with most studies reporting no differences (Marques et al., 2017; Jolazadeh et al., 2019; Brandão et al., 2020; Shao et al., 2021a, 2023) and only 1 study (Bellows et al., 2001) demonstrating heavier birth BW for offspring born from dams offered vs. not offered prepartum supplementation of fat.

Maternal supplementation of protein and energy during gestation often led to heavier BW at weaning compared to no maternal supplementation (Moriel et al., 2021; Izquierdo et al., 2022; Palmer et al., 2022; Vedovatto et al., 2022). In contrast, maternal supplementation of high-PUFA ingredients (oilseeds and Ca salts of ω- 3 and ω-6 fatty acids) during late gestation resulted in inconsistent offspring preweaning growth, with studies reporting no differences (Marques et al., 2017; Brandão et al., 2020; Shao et al., 2023), increased (Bellows et al., 2001; Jolazadeh et al., 2019; Ricks et al., 2020), or decreased (Shao et al., 2021a) weaning BW for offspring born from cows provided PUFA vs. SFA/MUFA or no fat supplementation. Supporting our hypothesis, maternal prepartum supplementation of HFAT and LFAT bakery waste increased first offspring BW at weaning on average by 12 kg compared to NOSUP offspring. Treatment-induced differences in milk production of cows are possible, but less likely, because 1) enhanced calf preweaning growth has been detected despite no differences in cow milk production following maternal supplementation of protein and energy during late gestation (Marques et al., 2016) and PUFA (Shao et al., 2021a, 2023); and 2) first offspring preweaning BW in the present study started to differ after the start of the breeding and beyond the peak of cow milk production (NASEM, 2016). Moreover, first offspring BW at weaning increased at greater extent for those born from LFAT cows and was on average 10 kg heavier for LFAT vs. HFAT bakery waste, supporting the results reported by Shao et al. (2021a) who observed an increase on progeny weaning BW of 9 kg when cows received prepartum supplementation of Ca salts of SFA/MUFA vs. PUFA. The discrepant amount, source, and profile of fatty acids utilized herein and in previous studies likely explain the inconsistent results on offspring BW at birth and weaning. Absolute amount and ratio of ω-3 and ω-6 fatty acids impacted animal health and growth (Papadopoulos et al., 2009) and likely determine if maternal PUFA supplementation will promote adipogenic or myogenic genes in the offspring and impact or not their postnatal growth performance (Brandão et al., 2020; Shao et al., 2021a,b) compared to SFA/MUFA and no prepartum supplementation. In addition, the contradictory response to similar management of Bos indicus-influenced vs. Bos taurus cattle (Cooke et al., 2020) may have also played a role on the results reported herein.

Preconditioning

The added calf BW observed at weaning following maternal supplementation of protein and energy during late gestation did not consistently carry over during subsequent periods compared to no maternal prepartum supplementation (Moriel et al., 2021). Likewise, maternal prepartum supplementation of Ca salts of ω-3 and ω-6 fatty acids consistently had no carry-over effects on offspring growth performance during preconditioning (Marques et al., 2017; Brandão et al., 2020) and backgrounding periods (Shao et al., 2023) compared to maternal prepartum supplementation of Ca salts of SFA/MUFA or no supplemental fat. In agreement, maternal prepartum supplementation of LFAT and HFAT supplements did not impact calf daily DM intake, ADG, and G:F during preconditioning. It is important to highlight, however, that maternal supplementation of protein and energy (Palmer et al., 2022) and Ca salts of ω-3 and ω-6 fatty acids (Marques et al., 2017; Brandão et al., 2020; Shao et al., 2023) improved carcass weight or quality at slaughter. Reasons for carry-over effects of maternal supplementation of protein, energy, and specific fatty acids being observed during finishing, but not during preconditioning, are unknown and may be related to the variable effects of maternal gestational nutrition on progeny immune function (Moriel et al., 2021), impacting nutrient partitioning for growth and stress-induced activation of the immune system at different extent (Carroll and Forsberg, 2007), but also modifications to morphology and metabolism of muscle fiber and adipocyte (Du et al., 2010).

Prenatal exposure to stress can imprint and modulate offspring immune response (Littlejohn et al., 2016). In the present study, average plasma concentrations of haptoglobin did not differ among all maternal treatments, whereas average plasma concentrations of cortisol did not differ between NOSUP and LFAT offspring. Previous studies utilizing the same research site, cattle subspecies, and vaccination protocol as herein did not observe an impact of maternal prepartum supplementation of protein and energy from low-fat ingredients on progeny vaccine-induced plasma concentrations of cortisol (Moriel et al., 2020; Palmer et al., 2022) and haptoglobin (Moriel et al., 2016; Palmer et al., 2022). The unexpected response was the reduction in plasma concentrations of cortisol for first offspring born from HFAT vs. NOSUP cows. Maternal prepartum supplementation of ω-3 and ω-6 fatty acids did not impact offspring weaning-induced plasma concentrations of cortisol but reduced plasma concentrations of haptoglobin compared to maternal prepartum supplementation of SFA/MUFA (Marques et al., 2017). Different sources of stress (vaccination vs. weaning) may explain the diverse outcome to plasma concentrations of cortisol and haptoglobin observed in the present study and by Marques et al. (2017). Nevertheless, maternal prepartum supplementation of PUFA alleviated offspring inflammatory response in both studies perhaps due to the immunomodulatory effects of PUFA (Araujo et al., 2010; Cooke et al., 2011). The reduction on inflammatory response was minor and likely not sufficient to partition enough nutrients away from growth towards the immune system to impact preconditioning ADG of HFAT vs. NOSUP offspring.

Maternal prepartum supplementation of energy and protein improved postweaning humoral immune response of the offspring (Moriel et al., 2016, 2020; Palmer et al., 2022). Steer progeny born to cows offered prepartum supplemental protein and energy had increased serum titers and seroconversion against PI₃ (Moriel et al., 2020; Palmer et al., 2022) and BVDV-1 (Moriel et al., 2020) compared to steers born from nonsupplemented cows. In the present study, postvaccination humoral immune response of the first offspring varied according to maternal treatment and virus type. Maternal treatments did not impact serum titers and positive seroconversion against BVDV-1 and serum titers against PI₃. At weaning, maternal treatments did not impact offspring serum titers against IBR and positive seroconversion against PI₃, whereas serum titers and positive seroconversion against BRSV were less for HFAT vs. LFAT offspring and less for HFAT vs. LFAT and NOSUP offspring, respectively. At the first round of vaccination (day 315), positive seroconversion against IBR and BRSV did not differ among all treatments but serum titers against IBR were greater for HFAT vs. LFAT offspring and positive seroconversion against PI₃ were greater for HFAT vs. LFAT and NOSUP offspring. At the end of the preconditioning period (day 345), serum titers against IBR and BRSV were greater for HFAT vs. LFAT offspring and intermediate for NOSUP, whereas positive seroconversion against IBR, PI₃, and BRSV did not differ among all treatments. A clear explanation for the complex responses detected herein was not identified. Overall, maternal supplementation of HFAT bakery waste improved offspring humoral immune response during preconditioning period compared to LFAT supplementation and had minor benefits to offspring vaccine response (greater PI₃ positive seroconversion on day 315) compared to no maternal prepartum supplementation. The impact of such finding is minimized considering that calves were preconditioned and remained at the research site. However, it is possible that the detected maternal treatment-induced changes to offspring immune function might be beneficial to calves in a more challenging scenario (e.g., following commercial feedlot entry immediately after weaning).

Conclusions

Maternal prepartum supplementation of bakery waste, regardless of crude fat concentration, increased maternal plasma concentrations of PUFA and BCS at calving, compared to no prepartum supplementation. However, providing bakery waste supplementation with high concentrations of crude fat led to the greatest cow BCS and plasma concentrations of PUFA and ɷ-6 at the start of the breeding season leading to greater percentage of cows calving during the first 21 d of the calving season compared to cows provided no supplementation or supplementation of bakery waste with low crude fat concentration. Prepartum maternal supplementation of bakery waste, regardless of crude fat concentration, did not alter birth body weight of the first offspring but increased offspring weaning weights compared to no prepartum supplementation. However, weaning weights of the first offspring increased to the greatest extent when cows were offered bakery waste with low concentrations of crude fat during the last trimester of gestation. Moreover, maternal supplementation of bakery waste with high concentrations of crude fat increased postvaccination inflammatory response compared to low-fat bakery waste supplementation and had minor benefits to progeny humoral immune response compared to no maternal prepartum supplementation. Overall, selecting different crude fat concentrations in bakery waste can be implemented during third trimester of gestation to increase cow body condition score at calving and positively modulate offspring preweaning growth or postweaning immune response to vaccination.

Glossary

Abbreviations:

ADG

average daily gain

ADICP

Acid detergent insoluble crude protein

BCS

body condition score

BRSV

bovine respiratory syncytial virus

BVDV-1

bovine viral diarrhea virus type 1

BW

body weight

CP

crude protein

DM

dry matter

ESC

Ethanol-soluble carbohydrates

G:F

gain:feed

HCW

hot carcass weight

HFAT

high fat bakery waste

IBR

infectious bovine rhinotracheitis

IGF-1

insulin-like growth factor 1

IVDOM

in vitro digestible organic matter

LFAT

low fat bakery waste

MUFA

monounsaturated fatty acids

NEg

net energy for gain

NEm

net energy for maintenance

NFC

nonfibrous carbohydrate

NOSUP

no supplementation

PI-3

parainfluenza-3 virus

PUFA

polyunsaturated fatty acids

SFA

saturated fatty acids

Conflict of interest statement

Authors declare that there are no conflicts of interest in this study.