Table 2.

Reuse of spent mushroom substrate (SMS) as animal feed based on the outcome reported in pertinent publications. Abbreviations used: ADF, acid detergent fiber; ADL, acid detergent lignin; HWE, hot water extract; NDF, neutral detergent fiber; NR, not reported; S-SMS: steam-treated SMS; UN-SMS: untreated SMS.

Origin of SMS	SMS content in fibers and crude protein			Animals in feeding trials	Type of feed, inclusion levels, and length of feeding trials	Main outcome	Ref.
	NFD, ADF and ADL (%)	Crude fiber (%)	Protein (%)
Pleurotus sajor-caju	60.3, 52.3, 4.1	NR	9.3	Alpine dairy goats	Rice straw fermented with P. sajor-caju SMS (5:1 w/w for 8 weeks), diet and water provided ad libitum, 28 days	SMS effectively improved the nutrient content, availability in the rumen, and feeding value of rice straw; increased effective degradability of dry mater and fibers in the rumen; improved intake and milk yield	[61]
Pleurotus ostreatus	NR	NR	3.0	Male Sika deers	SMS (10%), 60 days	SMS led to reduction in the intake of organic matter, and improved digestibility of crude fat	[62]
Flammulina velutipes	NR	NR	5.1			Νo effect on apparent nutrient digestibility, feed intake, velvet antler production, or biochemical indexes
P. ostreatus	NR	NR	NR	Liuyang black goats	SMS co-fermented with feed and whole plant rice, 60 days	Feeding with co-fermented whole plant rice and SMS had no adverse effect on the slaughter performance, while the meat quality was improved	[63]
Cordyceps militaris	NR	NR	NR	Crossbred growing pigs	SMS (0.2%, w/w), 6 weeks	SMS increased final body weight and daily weight gain, immunoglobulin A and G, and the rest of the parameters were not affected.	[55]
Lentinula edodes	NR	NR	NR	Weaned piglets	SMS (3%) fermented by Bacillus subtilis, 33 days	Increase in final weight, daily gain and feed conversion; beneficial effect on the intestinal mucosal barrier, and immunity	[64]
Ganoderma lucidum	NR	NR	23.6	Mice	HWE of SMS (0.14, 0.28, 0.84 and 1.68 g kg−1), 30 days	HWE of SMS enhanced murine immune function; the 0.84 g/kg dose had optimal effect in all aspects	[65]
P. ostreatus	74.8, 49.4, NR	24.2	7.9	Hanwoo steers	SMS fermented or not with Lactobacillus brevis, 13 days	SMS (fermented or not) could replace formulated feed concentrate without adverse effects	[66]
P. ostreatus	73.6, 55.0, NR	NR	8.1	Geese	SMS fed ad libitum during the growing period, 8 weeks)	SMS supplementation at 5% had no adverse effects on the growth performance, while it favorably affected sensory attributes	[67]
Pleurotus eryngii	50.6*, 38.9*, 11.7*	31.2*	16.9*	Sheep	By-product feed silage with fermented SMS (45%), 22 days	The SMS-containing feed showed similar energy value, higher protein metabolism and utilization, and lower fiber digestion than the rye straw-based control diet	[68]
P. ostreatus	NR	NR	5.6	Awassi sheep	SMS (5, 10, 15 and 20%), 70 days	SMS ratios (>15%) decreased slaughter, empty body, and carcass weights, dressing, leg lean and fat tail percentage, backfat thickness, and rib eye area	[69]
P. ostreatus	76.7, 61.2, 15.5	NR	13.4	Hanwoo steers	Feed containing 50% SMS; ad libitum access during the growing and fattening periods	Trials with by-product feed tended to increase the average daily weight gain and feed efficiency, while it did not affect quality and yield traits	[70]
G. lucidum	NR	6	23.6	Holstein cows	HWE of SMS (33, 67, and 100 g d−1 cow−1), 60 days	HWE of SMS may enhance immunity and antioxidant capacity in dairy cows, and subsequently improve milk quality	[71]
Ganoderma chalceum(syn. G. balabacense)	NR	NR	23.6	Chinese Holstein cows	HWE of SMS (33, 67, and 100 g d−1 cow−1), 60 days	Feeding by HWE of SMS improved hematology parameters, and increased milk yield, milk protein and triglyceride levels	[72]
Agaricus bisporus	27.8, NR, 6.9	13.3	12.9	Holsteins male calves	SMS (15%), 170 days	No differences detected in the carcass and internal organs of the calves that received different diets	[73]
P. ostreatus	NR	29.6	7.9	Broilers	SMS substituted wheat bran (by 25–100%), 8 weeks	Higher feed intake with increased rate of SMS inclusion; SMS did not affect breast, thigh drumstick, back, neck, wings, and shoulder weight	[74]
Hypsizygus marmoreus	NR	-	-	Laying hens	SMS (5, 10 and 15%) fermented with Bacillus subtilis, 12 weeks	Feed intake increased with SMS addition; no differences in egg production, egg weight, egg mass, feed conversion and viability; the yolk color was more intense when SMS was added	[75]
Grifola frondosa	Steam-treated SMS (S-SMS) and non-treated SMS (N-SMS)	NR	6.6(S-SMS), 6.4 (N-SMS)	Wistar rats	S-SMS or N-SMS (25%), 26 days	Feed with SMS did not affect body weight gain, feed efficiency, or serum biochemical parameters; however, fecal weight and protein content were significantly higher than the control	[76]
P. eryngii	78.8, 66.0. 12.8	NR	5.7	Hanwoo steers during growing and fattening periods	Ad libitum access to microbially-fermented SMS (50%), 12.6 months	Feeding with microbially fermented SMS improved growth performance and carcass traits, and could successfully replace a part of conventional roughage	[77]
P. ostreatus	65.1, 49.4, NR	40.5	15.4	Postweaning calves	SMS (10%) fermented or not with lactic acid bacteria, 60 days	The fermented SMS improved the growth performance compared to non-fermented SMS and to feed with an antibiotic supplement	[78]
P. eryngii	NR	NR	NR	Laying hens	SMS (5, 10 and 15%) fermented with Bacillus subtilis, 7 weeks	Feed intake increased with SMS addition; no differences noted in egg production, egg weight, egg mass, feed conversion and viability; yolk color was more intense when SMS was added	[79]
P. sajor-caju	NR	NR	6.3	Broiler chicken	SMS (0.5 to 2%), 21 or 38 days	The inclusion of SMS up to 0.67% improved the weight gain of broiler chicks in the first 21 days	[80]
Agaricus blazei	NR	NR	NR	Broiler chicks	SMS (0.2 to 1.0%), 42 days	SMS above 0.4% reduced the animals’ performance; 0.2% SMS resulted in the highest weight gain and feed intake, and the best feed conversion	[81]
P. ostreatus	NR	9.4	17.6	Berkshire pigs	SMS (plus rice bran and barley bran, 2:1:1) in ratios of 3, 5 or 7%, 7 weeks	Daily feed intake and feed conversion increased through SMS addition; SMS (3%) positively affected the growth performance, carcass traits, meat quality and fatty acids concentration in meat	[82]
A. bisporus	27.8, 21.0, 6.8	17.8	11.0	Sheep	SMS (10, 20, 30%), 3 weeks	Up to 20% SMS did not affect nutrient intake, digestibility, or nitrogen balance	[83]

*Values referrer to bioproduct-feed with SMS (45%).