Effects of maternal supplementation with an injectable trace mineral on subsequent calf performance and inflammatory response

Abstract

Newly weaned, commercial Angus steers [body weight (BW) = 204 ± 19 kg; n = 24; 12 steers from dams administered an injectable trace mineral (MM; Mulimin90) and 12 steers from control (CON) dams] were utilized to determine the effects of maternal supplementation with an injectable trace mineral on the inflammatory response of subsequent steers subjected to a lipopolysaccharide (LPS) challenge at the initiation of a 42-d receiving period. On day −2 steers were weaned, and the following day, shipped 354 km to the Beef Cattle and Sheep Field Laboratory in Urbana, IL. On day 0, steers were administered an intravenous LPS challenge. Body temperature and blood samples were collected from steers prior to LPS administration (0 h) and again at 0.5, 1, 2, 3, 4, 5, and 6 h. Blood samples were analyzed for trace mineral and cortisol at 0 and 2 h and glucose, insulin, LPS-binding protein (LBP), interleukin-1β (IL-1β), interleukin-6 (IL-6), haptoglobin, ceruloplasmin, and fibrinogen at 0, 0.5, 1, 2, 3, 4, 5, and 6 h. Calf BW was collected at trial initiation and subsequently every 14 d. Dry matter intake was collected daily and average daily gain (ADG) and feed efficiency were assessed. Initial plasma Zn tended (P = 0.06) to be greater for MM steers. However, there was no difference (P ≥ 0.31) in trace mineral status or serum cortisol at any other time. Total area under the curve (TAUC) for body temperature was lesser (P > 0.01) for MM steers. Basal LBP concentrations and TAUC for LBP tended (P ≤ 0.10) to be greater for MM steers. Peak concentration of IL-6 tended (P = 0.09) to be reached earlier for CON steers. However, there was no difference (P ≥ 0.11) in glucose, insulin, IL-6, ceruloplasmin, haptoglobin, and fibrinogen concentrations between treatments. Calf performance and feed efficiency did not differ (P ≥ 0.17) between treatments except ADG from day 28 to 42, which was greater (P = 0.03) for CON steers. Maternal supplementation with an injectable trace mineral tended to improve steer plasma Zn status at 0 h and tended to increase basal concentrations of LBP and overall LBP production when steers were administered an LPS challenge. Additionally, MM steers exhibited a more favorable change in body temperature following LPS administration. However, injectable trace mineral supplementation of dams during gestation had minimal to no effect on cytokine and acute-phase protein concentrations, as well as overall calf performance and efficiency during a 42-d receiving period.

Introduction

Upon arrival to a feedlot, calves experience stress which coincides with greater susceptibility to an immune challenge. In addition to transportation stress, other compounding stressors may include weaning and comingling. Bovine respiratory disease or “shipping fever” is the leading causes of morbidity and mortality in feedlot cattle (USDA, 2011). Additionally, as the use of antibiotics to treat these costly diseases comes under more scrutiny, and as the livestock industry works to diminish the use of antibiotics, the need for alternative therapies to both prevent and minimize disease becomes critical.

The concept of developmental or fetal programming suggests that a maternal stimulus that alters the fetal environment could have long-term effects on the offspring (Wallace, 1948). Fetal growth and development can be influenced by genetics, environment, maternal maturity, and nutrition (Wu et al., 2006). While the effects of maternal macronutrient restriction are the most studied and have been reviewed (Wu et al., 2006; Funston et al., 2010), the effects of maternal trace mineral supplementation on subsequent calf performance and health are minimally studied. Trace minerals play a critical role in numerous biochemical processes and are a key component of an animal’s health and productivity. Recent research has focused on the positive impacts of trace mineral nutrition on the inflammatory response in beef cattle (Berry et al., 2000; Arthington et al., 2014; Genther-Schroeder and Hansen, 2015). Nutritional deficiencies in Cu, Mn, Se, and Zn impair immune defense parameters, and while the exact mechanism these trace mineral work to modulate the inflammatory response remains unclear, it is likely these trace minerals work in concert through specific mechanisms to execute a coordinated inflammatory response within the animal.

Copper is a key component in the formation of many Cu-containing proteins, most notably ceruloplasmin, a copper transport protein which serves as a marker of acute inflammatory stress (Hsieh and Frieden, 1975). Manganese serves as a cofactor for many enzymes including pyruvate carboxylase and phosphoenolpyruvate carboxykinase in gluconeogenesis (Leach and Harris, 1997) and may impact glucose and insulin regulation during an inflammatory response. Selenium is responsible for modifying the expression of selenoproteins (Sunde, 1997) and is a component of glutathione peroxidase (Reddanna et al., 1989). Over 2,000 transcription factors require Zn, and almost every metabolic or signaling pathway is dependent of a zinc-requiring protein (Suttle, 2010). These trace minerals play a critical role in proper inflammatory response, but the impact of when and how these trace minerals are provided and how this may modulate the immune response is yet to be fully understood. Therefore, the objective of this study was to determine the effect of maternal injectable trace mineral supplementation (Cu, Mn, Se, and Zn) on subsequent calf performance and health. We proposed that maternal supplementation with an injectable trace mineral during gestation would positively impact the inflammatory response of subsequent progeny when subjected to a lipopolysaccharide (LPS) challenge.

Materials and Methods

All experimental procedures were approved by the Institutional Animal Care and Use Committee of the University of Illinois (IACUC #18007) and followed the guidelines recommended in the Guide for the Care and Use of Agricultural Animal in Agricultural Research and Teaching (FASS, 2010).

Animals and Experimental Design

Newly weaned, commercial Angus steers [body weight (BW) = 204 ± 19 kg; mean ± standard deviation; n = 24; 12 steers from dams administered an injectable trace mineral (MM; Multimin90; Multimin USA, Fort Collins, CO) and 12 steers from control (CON) dams] were utilized to determine the effects of maternal supplementation with an injectable trace mineral on the inflammatory response of subsequent steers subjected to an LPS challenge. Dam treatments and previous calf performance and mineral status were reported by Stokes et al. (2018, 2019; Supplementary Appendix 1). In brief, dams were administered subcutaneous saline or trace mineral injections postweaning at 221, 319, and 401 ± 22 d of age (209, 111, and 29 d prior to AI, respectively). Treatments were maintained and administered 205, 114, and 44 ± 26 d prepartum. The first 12 AI sired bull calves born from MM dams and the first 12 AI sired bull calves born from CON dams were utilized in the present experiment. Steers were born from 4 AI sires. At birth, steers were administered injections of vitamin A, D, and E. Steers were vaccinated and booster vaccines of Bovishield Gold FP5 VL5 HB (Zoetis, Florham Park, NJ), Covexin 8 (Merck Animal Health, Madison, NJ), and Pulmo-Guard MpB (AgriLabs, St. Joseph, MO) were administered at 121 and 159 ± 26 d of age, respectively. Dams and their steers were housed at the Dixon Springs Agricultural Center in Simpson, IL and were given access to free-choice inorganic trace minerals (Renaissance Nutrition, Roaring Springs, PA; 0.24% S, 21.37% Ca as calcium carbonate, 2.99% P as monocalcium phosphate, 24.5% salt, 9.35% Na, 5.84% Mg as magnesium oxide, 0.06% K, 2,214 mg/kg Fe as iron oxide, 2,000 mg/kg Mn as manganous oxide, 2,500 mg/kg Zn as zinc oxide, 1,500 mg/kg Cu as copper sulfate, 27 mg/kg Co as cobalt carbonate, 36 mg/kg I, 26 mg/kg Se as sodium selenite, 110,179 IU/kg vitamin A, 3,084 IU/kg vitamin D, and 545 IU/kg vitamin E) and consumed 54.6 g per pair per day. On day −14, prior to weaning, dams and steers were given access to GrowSafe bunks (GrowSafe System Ltd, Airdrie, AB, Canada) to allow for calf adaptation to bunks. Diets consisted of 33% dried distillers grains with solubles, 17% soybean hull pellets, 25% shelled corn, 20% ground corn, and 5% supplement [66% neutral detergent fiber (NDF), 51% acid detergent fiber (ADF), and 11.7% crude protein (CP)]. On day −2 steers were weaned, and the following day they were shipped approximately 354 km to the Illinois Beef Cattle and Sheep Field Laboratory in Urbana, IL. Upon arrival, steers were weighed and assigned to pens based on treatment, with an equal representation of each treatment within pen (6 steers per pen; 3 MM steers and 3 CON steers per pen). Steers were housed in barns on slatted concrete floors covered by interlocking rubber matting. Pens were constructed of 5.08 cm galvanized steel tubing and were 4.88 × 4.88 m in dimension. Steers were given ad libitum access to a receiving ration (Table 1) from day −1 to day 7 and were then transferred to a growing diet for the remainder of the 42-d trial. Steers were weighed every 14 d and individual dry matter intake (DMI) was collected daily via GrowSafe bunks to assess average daily gain (ADG) and feed efficiency (G:F). Calf health was monitored daily by trained farm personnel for the 42-d receiving period. Steers were observed for general signs of illness including lethargy, decreased intake, labored breathing, and nasal discharge. Steers identified exhibiting these symptoms were treated by trained farm personal per veterinarian recommendations. Four steers died (2 CON and 2 MM) from pulmonary edema, due to complications following the completion of the LPS challenge and were removed from trial. All data from these steers were included in analysis until the time of removal.

Table 1.

Ingredient and nutrient composition of calf diets (% dry matter basis)

Item	Inclusion
	Receiving1	Growing2
Ingredient, %
High moisture corn	–	15
Modified distillers grains	40	15
Corn silage	–	35
Hay	50	25
Supplement	10	10
Analyzed nutrient content
Crude protein, %	16.6	10.9
NDF,3 %	52.5	42.1
ADF,4 %	26.4	21.3
Crude fat, %	5.6	3.3
Cu, mg/kg	10.2	8.8
Mn, mg/kg	54.2	43.0
Zn, mg/kg	48.4	43.5

¹Receiving diet was provided from day −1 to 7.

²Growing diet was provided from day 8 to 42.

³Neutral detergent fiber.

⁴Acid detergent fiber.

Sample Collection and Analytical Procedures

Upon arrival steers were fitted with commercially available jugular catheters (AniCath L/A 16 g × 13 mm; Millpledge Veterinary, Clarborough, Nottinghamshire, United Kingdom). Following insertion, catheters were flushed with a minimum of 6 mL sterile heparinized saline (1,000 µg/mL) to prevent overnight clotting. Catheters were secured to the neck with polypropylene suture (Ethicon US, LLC, Blue Ash, OH) and covered with a denim patch and Syrflex cohesive bandage (Neogen Corporation, Lexington, KY) between sample collections. Patches were attached on 3 sides with livestock identification tag cement (W.J. Ruscoe Company, Akron, OH). One side of the patch remained unattached to provide access to the catheter. Fifteen hours following arrival (day 0), steers were weighed and administered an intravenous LPS (0.5 µg/kg of BW of LPS from Escherichia coli O111:B4; Sigma-Aldrich, St. Louis, MO) challenge. Following administration of LPS, catheters were flushed with 8 mL of sterile saline to ensure all LPS were cleared from the catheter. Blood samples were collected prior to LPS administration (0 h) and again at 0.5, 1, 2, 3, 4, 5, and 6 h post-LPS administration. Following blood collection, catheters were flushed with a minimum of 6 mL heparinized saline (1,000 µg/mL) to prevent clotting. At each of these time points rectal temperatures were collected from steers. Ambient temperature during the day of LPS administration ranged from −1.6 to 8.9 °C. Four on-site handling facilities were used to process steers to ensure all blood samples were drawn at the proper time.

Blood samples from all 8 time points were collected and analyzed for plasma haptoglobin, plasma ceruloplasmin, plasma fibrinogen, serum interleukin-1β (IL-1β), serum interleukin-6 (IL-6), plasma glucose, plasma insulin, and plasma LPS-binding protein (LBP). Additional blood samples were collected at 0 and 2 h for serum cortisol and plasma trace mineral analysis. Approximately 9 mL of blood was collected into sodium citrate vacutainer tubes (Becton, Dickinson, and Co., Franklin Lakes, NJ) for fibrinogen analysis and 8 mL of blood was collected in lithium heparin vacutainer tubes (Becton, Dickinson, and Co., Franklin Lakes, NJ) for ceruloplasmin and haptoglobin analysis. Lithium heparin tubes were centrifuged at 1,500 × g for 10 min at 25 °C and sodium citrate tubes were centrifuged at 2,500 × g for 15 min at 25 °C. Plasma was removed and stored at −20 °C for subsequent analysis. Blood was collected into serum vacutainer tubes (10.0 mL; Becton, Dickinson, and Co., Franklin Lakes, NJ) for analysis of IL-1β, IL-6, and cortisol. Blood was collected in K_2EDTA vacutainer tubes (10 mL; Becton, Dickinson, and Co., Franklin Lakes, NJ) for glucose, insulin, and LBP analysis. Serum was allowed to clot for 2 h following collection. Samples were centrifuged at 1,300 × g for 20 min at 5 °C, and plasma and serum were stored at −80 °C until analysis. Blood for trace mineral analysis was collected into trace element vacutainers (6.0 mL; Becton, Dickinson, and Co., Franklin Lakes, NJ), and tubes were centrifuged at 1,300 × g for 10 min at 25 °C. Plasma was removed and stored at −20 °C until further analysis.

Serum IL-1β and IL-6 concentrations were analyzed using commercially available Bovine ELISA reagent kits (Bovine IL-1β ELISA reagent kit; Invitrogen Corporation, Grand Island, NY; intra-assay CV = 3.08 and inter-assay CV = 7.31; Bovine IL-6 ELISA reagent kit; Thermo Scientific, Rockford, IL; intra-assay CV = 4.29 and inter-assay CV = 6.05). Samples for cortisol analysis were sent to the University of Illinois Veterinary Diagnostic Laboratory and were tested on a Immulite 1000 (Siemens Healthineers, Erlangen Germany). Glucose concentrations were determined using the Glucose LiquiColor Procedure (No. 1070; Stanbio Laboratory, Boerne, TX; intra-assay CV = 2.03 and inter-assay CV = 1.60) and insulin concentrations were analyzed using a commercially available bovine insulin ELISA kit (Bovine Insulin Elisa, Alpco, Salem, NH; intra-assay CV = 3.56 and inter-assay CV = 3.51). Concentrations of LBP were determined using a human LBP ELISA kit (Multispecies reactive; Cell Sciences, Newburyport, MA; intra-assay CV = 4.55 and inter-assay CV = 12.66). Plasma samples for trace mineral analysis were sent to Michigan State University Diagnostic Center for Population and Animal Health (East Lansing, MI) and concentrations of Cu, Mn, Se, and Zn were analyzed using an Agilent 7500ce Inductively Coupled Plasma Mass Spectrometer (ICP/MS; Agilent Technologies Inc., Santa Clara, CA) via procedures described previously (Wahlen et al., 2005).

Feed ingredients were collected every 14 d for nutrient composition analysis. Samples were dried at 55 °C for a minimum of 3 d and ground through a 1-mm screen using a Wiley mill (Arthur H. Thomas, Philadelphia, PA). Samples were analyzed for CP (Leco TruMac, LECO Corporation, St. Joseph, MI), NDF and ADF using an Ankom 200 Fiber Analyzer (Ankom Technology, Macedon, NY), and crude fat using an Ankom XT10 fat extractor (Ankom Technology, Macedon, NY).

Statistical Analysis

Blood samples collected at 0 h, prior to administration of the LPS challenge, were utilized as the baseline concentration. Peak concentrations and peak time were recorded for haptoglobin, ceruloplasmin, fibrinogen, IL-1B, IL-6, glucose, insulin, and LBP. Additionally, the total area under the curve (TAUC) was calculated using the trapezoidal method and actual concentration values as described by Cardoso et al. (2011). Data were analyzed using the MIXED procedure of SAS (SAS Inst. Inc., Cary, NC) as a stratified randomized design. The model included the fixed effects of treatment, pen, and handling facility. Sire was analyzed and not significant and thus removed from the model. Steer served as the experimental unit for all analyses. Significance was declared at P ≤ 0.05 and tendencies were noted at 0.05 < P ≤ 0.10. Means reported in tables are least squares means ± SEM.

Results and Discussion

Prior to LPS administration, plasma Cu, Mn, and Se did not differ (P ≥ 0.55; Fig. 1) between treatments. However, there was a tendency for increased (P = 0.06) plasma Zn concentrations in steers from MM dams. Small decreases in plasma Zn concentrations may be a result of early deficiency (Underwood and Suttle, 1999). However, there are no clear storage pools of Zn in the body and numerous other factors have been shown to manipulate blood mineral concentrations including the physiological state of the animal and presence of antagonists (Herdt and Hoff, 2011). Two hours post-LPS administration there were no differences (P ≥ 0.31) in plasma Cu, Mn, Se, or Zn concentrations, regardless of treatment. Despite these lack of differences, both treatments noted an over 70% decrease in plasma Mn concentrations and about a 30% decrease in plasma Zn concentrations. The decrease in plasma Zn was expected and has previously been reported in cattle when administered an LPS challenge (Zebeli et al., 2012). Interleukin-6 has been shown to mediate this change in circulating Zn concentrations by partitioning Zn to the liver (Savlov et al., 1962). This repartitioning of Zn may deprive infecting microbes of this essential trace element, inhibiting growth and replication without impacting host immunity (Sugarman, 1983). Though less understood, research has hypothesized that Mn may also be sequestered to allow resistance to bacterial infections (Kehl-Fie and Skaar, 2010). Manganese is also a component of Mn superoxide dismutase, an antioxidant, and sequestering Mn may be a form of nutritional immunity that allows the host to mount an antibacterial immune response via oxidative stress (Weiss and Carver, 2018).

Figure 1.

Influence of maternal injectable trace mineral supplementation on calf plasma mineral status following the administration of a lipopolysaccharide immune challenge. Control dams received a sterilized saline solution, and Multimin90 (MM) dams received injectable trace mineral at approximately 90-d intervals during gestation. Time 0 h was collected prior to the administration of the lipopolysaccharide challenge. At 0 h there was a tendency for MM calves to have greater (P = 0.06) plasma Zn concentrations compared to control. However, trace mineral status was not different (P ≥ 0.31) between treatments at any other time point.

Steer serum cortisol concentrations did not differ (P ≥ 0.43; Fig. 2) between treatments prior to LPS administration, or 2 h post-LPS administration. Unstressed cattle typically exhibit plasma cortisol levels ranging from 1 to 18 ng/mL (Rhynes and Ewing, 1973; Lefcourt et al., 1993). Based on this basal range of cortisol, initial cortisol concentrations of steers was already elevated prior to administration of LPS. This was not surprising though as these steers had been recently weaned, shipped, processed through the chute, and fitted with jugular catheters prior to the collection of this initial sample. Two hours following the LPS challenge cortisol concentrations rose to over 70 ng/mL. This is comparable to work by Carroll et al. (2009) who reported that steers exposed to an LPS challenge reached serum cortisol concentrations of 99 ng/mL and peak concentration was reached 3.4 h post-challenge. Increased circulating cortisol may serve as an effector molecule for the innate immune system and may stimulate early physiological responses following an LPS challenge (Carroll et al., 2009).

Figure 2.

Influence of maternal injectable trace mineral supplementation on calf serum cortisol concentration following the administration of a lipopolysaccharide immune challenge. Control dams received a sterilized saline solution, and Multimin90 (MM) dams received injectable trace mineral at approximately 90-d intervals during gestation. Time 0 h was collected prior to the administration of the lipopolysaccharide challenge. Serum cortisol was not different (P ≥ 0.43) between treatments at any time point.

Base rectal body temperatures were relatively elevated (steers from CON dams = 39.5 °C and steers from MM dams = 39.3 °C, compared to a normal resting body temperature for cattle of 38.6 °C) prior to LPS administration; however, there was no difference (P = 0.13; Table 2) between treatments. Peak temperature and time of peak temperature did not differ (P ≥ 0.49) regardless of treatment. Interestingly, steers from MM dams had a decreased (P < 0.01) TAUC for rectal body temperature compared to steers from CON dams. These data suggest that once reaching peak body temperature, steers from MM dams were able to recover and return to baseline temperatures more efficiently. Jacometo et al. (2015) supplemented gestating Holstein cows with inorganic or organic Zn, Mn, Cu, and Co and noted that steers from organic-supplemented dams tended to have lower rectal temperatures 7 and 21 d after birth. This change was noted despite steers having no difference in plasma Cu, Mn, Fe, or Zn. However, Genther-Schroeder and Hansen (2015) noted that in weaned steers experiencing shipping stress, rectal temperature was not affected by mineral status.

Table 2.

Influence of maternal injectable trace mineral supplementation on calf body temperature and blood metabolites over a 6-h period following the administration of a lipopolysaccharide immune challenge

	Treatment1		SEM	P-value
Item	Control	MM
Body temperature
Base temperature,2 °C	39.5	39.3	0.12	0.13
Peak temperature, °C	40.6	40.6	0.10	0.90
Peak time, min	163	140	22.5	0.49
TAUC3	25,356	21,480	876.0	<0.01
Glucose
Base concentration,2 mg/dL	86.6	91.8	2.45	0.15
Peak concentration, mg/dL	124.4	118.7	6.59	0.55
Peak time, min	43	45	6.5	0.79
TAUC3	27,445	28,396	909.1	0.47
Insulin
Base concentration,2 mg/dL	1.06	0.64	0.249	0.25
Peak concentration, mg/dL	4.71	7.54	1.368	0.16
Peak time, min	125	125	4.7	1.00
TAUC3	8.2	8.2	1.66	1.00
LBP4
Base concentration,2 µg/mL	2.50	4.68	0.855	0.09
Peak concentration, µg/mL	11.24	11.32	0.591	0.92
Peak time, min	210	245	25.1	0.33
TAUC3	3,488	4,359	350.0	0.10

¹Control dams received a sterilized saline solution, and Multimin90 (MM) dams received injectable trace mineral at approximately 90-d intervals during gestation. Data reported are from subsequent steer calves.

²Base represents the initial value or concentration determined at time 0 h, prior to the administration of the lipopolysaccharide challenge.

³Total area under the curve.

⁴Lipopolysaccharide-binding protein − nonpathological levels of LBP = 2 µg/mL and can increase up to 7-fold in calves following experimental infections (Schroedl et al., 2001).

Both the action of cytokines and fever have been shown to modulate feed intake and the activity of glucose-responsive neurons in the hypothalamus (Hori et al., 1991). However, base concentration, peak concentration, time of peak concentration, and TAUC did not differ (P ≥ 0.15) for both glucose and insulin, regardless of treatment. As expected with immune-challenged animals, a quick rise (43 and 45 min to peak concentration for steers from CON and MM dams, respectively) in circulating glucose was noted to fuel the upregulation of immune cells (Spurlock, 1997). Even moderate infections can result in a 150% to 200% increase in the rate of gluconeogenesis in the infected host (Lochmiller and Deerenberg, 2000). This rise in plasma glucose concentration was then followed by an increase in plasma insulin. This repartitioning of nutrients for immune-related processes is a metabolically costly process and ultimately a key obstacle for animals to achieve maximal growth and efficiency.

The cytokines IL-1β and IL-6 are endogenous pyrogens that mediate fever by stimulating acute-phase proteins and activating the hypothalamic-pituitary-adrenal axis of the brain (Kozak et al., 1998). Despite differences between treatments for body temperature, there were no differences (P ≥ 0.42; Table 3) in base concentration, peak concentration, and TAUC for IL-1β and no differences (P ≥ 0.27) in base concentration, peak concentration, time of peak concentration, and TAUC for IL-6. There was, however, a tendency (P = 0.09) for steers from CON dams to reach peak concentration of IL-1β earlier than steers from MM dams. The difference noted between body temperature and these endogenous pyrogens may be explained by data from Kozak et al. (1998), who reported that in mice IL-1β and IL-6 may not be required for an LPS-induced fever. Kozak et al. (1998) hypothesized that tumor necrosis factor-α (TNF-α) may instead play a role in fever induction. Unfortunately, TNF-α was not assessed in this study, and therefore, it is unknown if this may have been driving the differences noted in steer body temperature.

Table 3.

Influence of maternal injectable trace mineral supplementation on calf markers of acute inflammatory stress and cytokines over a 6-h period following the administration of a lipopolysaccharide immune challenge

Item	Treatment1
	Control	MM	SEM	P-value
IL-1β 2
Base concentration,3 pg/mL	12.13	6.29	4.981	0.42
Peak concentration, pg/mL	125.3	125.6	25.03	0.99
Peak time, min	195	225	11.9	0.09
TAUC4	19,979	22,990	5,276.5	0.69
IL-65
Base concentration,3 pg/mL	1867.6	1107.0	779.04	0.50
Peak concentration, pg/mL	15391	16810	1293.9	0.45
Peak time, min	205	245	24.8	0.27
TAUC4	2,313,951	2,898,703	371,270	0.28
Ceruloplasmin
Base concentration,3 mmol/L	2.70	2.60	0.112	0.52
Peak concentration, mmol/L	2.85	3.03	0.121	0.32
Peak time, min	158	173	40.8	0.80
TAUC4	963	995	40.4	0.58
Haptoglobin
Base concentration,3 mmol/L	1.18	1.10	0.034	0.08
Peak concentration, mmol/L	2.18	2.28	0.156	0.64
Peak time, min	115	128	20.7	0.67
TAUC4	625	590	40.4	0.55
Fibrinogen
Base concentration,3 mg/dL	932.8	875.8	63.65	0.53
Peak concentration, mg/dL	1051.2	1179.3	53.46	0.11
Peak time, min	33	45	9.9	0.38
TAUC4	186,094	218,612	20,398	0.27

¹Control dams received a sterilized saline solution, and Multimin90 (MM) dams received injectable trace mineral at approximately 90-d intervals during gestation. Data reported are from subsequent steer calves.

²Interleukin-1β.

³Base represents the initial value or concentration determined at time 0 h, prior to the administration of the lipopolysaccharide challenge.

⁴Total area under the curve.

⁵Interleukin-6.

The biological activity of LPS circulating in the blood stream can be mediated by LBP, which accelerates the binding of LPS to CD14, a macrophage receptor that stimulates phagocytosis (Fenton and Golenbock, 1998). Nonpathological levels of LBP are typically around 2 µg/mL and can increase up to 7-fold in calves following experimental infections (Schroedl et al., 2001). Not only did steers from MM dams tend (P = 0.09) to have increased base concentrations of LBP, they also tended (P = 0.10) to exhibit a greater TAUC for LBP concentrations following the administration of an LPS challenge. Peak concentration of LBP and time of peak concentration were similar (P ≥ 0.33) for both treatments. Fenton and Golenbock (1998) revealed that LBP is required for a rapid inflammatory response and survival postinfection when mice are exposed to Salmonella, a gram-negative bacteria containing LPS. The increased production of LBP by immune-challenged steers from MM dams in the present experiment may have resulted in expedited activation of the acute immune response and may have facilitated a more rapid clearance of LPS from the host.

There were no differences (P ≥ 0.11) in base concentration, peak concentration, time of peak concentration, or TAUC for ceruloplasmin and fibrinogen. There were also no differences (P ≥ 0.55) in peak concentration, time of peak concentration, or TAUC for haptoglobin. There was a tendency (P = 0.08) for steers from CON dams to have an increased base concentration of haptoglobin compared to their MM counterparts. Plasma Cu concentrations of steers from both treatments were not different, and therefore the lack of difference in ceruloplasmin concentrations was not surprising, as ceruloplasmin is a Cu transport protein and is often reflective of plasma Cu status (Hsieh and Frieden, 1975). Jacometo et al. (2015) also reported no difference in calf blood ceruloplasmin and haptoglobin concentrations at 21 d of age when gestating dams were supplemented organic trace minerals. Additionally, trace mineral status of these steers was not different at 21 d of age (Jacometo et al., 2015). However, these steers were much younger and not exposed to an additional immune challenge. Arthington et al. (2014) noted that heifers that received an injectable trace mineral at birth and then again at 100 and 200 d of age had increased ceruloplasmin and haptoglobin concentrations and increased liver Cu, Se, and Zn concentrations following shipping stress compared to untreated controls. However, heifers utilized by Arthington et al. (2014) received direct administration of an injectable trace mineral and had altered mineral status, in contrast to the steers utilized in the present experiment, which makes drawing conclusions across these experiments challenging.

Likely driven by the minimal differences noted in immune parameters, calf performance, including BW, ADG, DMI, and G:F, did not differ (P ≥ 0.17; Table 4) at any time point except for day 28 to 42, when ADG was greater (P = 0.03) for steers from CON than MM dams. This interim 28 to 42 d ADG represents a short time and only single day BW were collected for these interim BW. During this time CON steers also had numerically increased DMI, though not statistically different. Though this single ADG time point is different, the more meaningful representation of these data would be reflected by the lack of difference in overall ADG. Jacometo et al. (2015) also noted no difference in calf BW or mineral status from birth to 8 wk of age when dams were supplemented organic or inorganic trace minerals during gestation. Similarly, Muehlenbein et al. (2001) supplemented gestating beef cows inorganic or organic copper and noted no difference in calf birth BW or weaning BW and no difference in calf serum Cu concentrations. These experiments both supplemented organic trace minerals to dams, and the steers in these experiments were overall healthy and not subjected to health or immune challenges. However, these data collectively suggest that even though maternal trace mineral status may have been altered during gestation, additional mineral supplementation to these gestating dams had little impact on subsequent calf mineral status and may not improve subsequent calf growth and performance.

Table 4.

Influence of maternal injectable trace mineral supplementation on calf performance during a 42-d receiving period following the administration of a lipopolysaccharide immune challenge

Item	Treatment1
	Control	MM	SEM	P-value
Body weight, kg
Day 0	207	201	5.9	0.48
Day 14	217	213	7.4	0.71
Day 28	224	218	7.3	0.55
Day 42	252	239	8.0	0.25
Average daily gain, kg/d
Day 0 to 14	0.76	1.29	0.277	0.17
Day 14 to 28	0.51	0.68	0.350	0.73
Day 28 to 42	1.99	1.48	0.150	0.03
Day 0 to 42	1.09	0.97	0.148	0.59
Dry matter intake, kg
Day 0 to 14	6.33	5.42	0.646	0.34
Day 14 to 28	10.72	9.63	0.657	0.25
Day 28 to 42	13.20	11.86	0.741	0.22
Day 0 to 42	10.05	9.42	0.516	0.40
G:F2
Day 0 to 14	0.116	0.192	0.0444	0.22
Day 14 to 28	0.070	0.054	0.0292	0.69
Day 28 to 42	0.158	0.133	0.0178	0.32
Day 0 to 42	0.106	0.111	0.0114	0.75

¹Control dams received a sterilized saline solution, and Multimin90 (MM) dams received injectable trace mineral at approximately 90-d intervals during gestation. Data reported are from subsequent steer calves.

²Feed efficiency is reported as gain to feed (G:F).

The present data demonstrate how maternal supplementation with an injectable trace mineral has minimal effect on subsequent calf growth and immune response following an LPS-induced immune challenge. Supplementing an injectable trace mineral to gestating dams tended to improve steer plasma Zn status at the time of weaning and steers from MM-supplemented dams tended to have increased basal concentrations of LBP and greater overall LBP production when administered an LPS challenge. Additionally, steers from dams supplemented an injectable trace mineral exhibited a more favorable change in body temperature following LPS administration. However, additional injectable trace mineral supplementation of dams during gestation had minimal to no effect on nutrient partitioning, cytokine and acute-phase protein production, and overall calf performance and efficiency. Additional research is needed to determine the role maternal trace mineral supplementation may be playing in LBP production as well as the mechanisms that may be altering body temperature during inflammation.