Development Of Solid-state Fermentated Distiller’s Grains Feed And Its Application On Goats

There are abundant white distiller’s grains in China,but the utilization rate of white distiller’s grains in China is not high due to its high water content,which makes it difficult to store and transport.Using solid-state fermentation technology can effectively improve the nutritional value of distiller’s grains.Fermented distiller’s grains feed is easy to store and transport and has rich nutritional content.Feeding the fermented distiller’s grains to goats is expected to reduce the feed cost and promote the healthy and sustainable development of goat industry.The purpose of this study was to screen the suitable strain combination and solid state fermentation technology for the production of fermented white distiller’s grains feed,and explore the application effect of fermented white distiller’s grains feed on goat production.Using Maotai-flavor distiller’s grains as fermentation substrate,Saccharomyces cerevisiae,Candida utilis,Bacillus subtilis,Bacillus licheniformis,Aspergillus niger and Aspergillus oryzae were used to design 8 combinations to perform SSF on the distiller’s grains.After selecting the suitable combination of fermentation strains,orthogonal experiment design was used to further optimize the fermentation substrate moisture,fermentation temperature and fermentation time.Finally,in solid-state fermentation workshop,the nutritional indexes and mycotoxins of distiller’s grains before and after fermentation were detected.Twenty-seven Dazu Black goat weaned lambs(female)with the body weight of 9.64±0.73 kg were randomly divided into three groups.Two experimental groups were fed basal diet + Maotai-flavor fermented lees(MFFDG)(50 g/d)(test group I)and basal diet +MFFDG(150 g/d)(test group Ⅱ),respectively,to study the effects of MFFDG on growth performance,serum hormone levels and nutrient apparent digestibility of weaned lambs.Twelve dazu black fattening sheep(female)with the body weight of 19.67±1.76 kg were randomly divided into two groups.The basal diet was supplemented with 5.90% maotai-flavor fermented lees(MFWDG group)and 5.90% Maotai-flavor fermented lees(MFFDG group),respectively.To study the effects of different maotai-flavoured distiller’s grains on growth performance,slaughter performance,organ development and meat quality of fattening sheep.The main results of this study are as follows:(1)All probiotics combinations significantly increased the true protein(TP)content in distiller’s grains(P<0.05).Group E(Saccharomyces cerevisiae+Candida utilis + Bacillus subtilis + Aspergillus niger + Aspergillus oryzae),group G(Saccharomyces cerevisiae + Aspergillus niger + Aspergillus oryzae)and group F(Saccharomyces cerevisiae + Candida utilis + Bacillus subtilis + Aspergillus oryzae +Bacillus licheniformis)had the best improvement effect.Compared with prefermentation,TP content increased by 16.87%,15.32% and 14.95%,respectively.The optimal fermentation parameters were 55% water content and 35 ℃ fermentation for4 days.After amplified production in SSF workshop,the contents of TP,CP and Ca in distiller’s grains were significantly increased compared with those before fermentation(P<0.05).The contents of crude fiber(CF)and organic matter(OM)were significantly decreased compared with those before fermentation(P<0.05).Compared with before fermentation,emetic toxin was significantly increased(P<0.05),while aflatoxin had no significant difference(P>0.05),and the contents of both were far lower than the limit level of national standard.(2)Weeks 1 to 12 of formal feeding,the average daily gain(ADG)of lambs in trial group I was significantly higher than that in control group(P<0.05),the feed to gain(F/G)in trial group I was significantly lower than that in control group(P<0.05),and there were no significant differences in ADG and F/G between trial group II and trial group I as well as between control group(P>0.05).There was no significant difference in average daily feed intake(ADFI)among the three groups during the whole experiment period(P>0.05).There were no significant differences in the levels of growth hormone-releasing hormone,somatostatin,insulin-like growth factor-1,growth hormone and ghrelin among three test groups(P > 0.05).There was no significant difference in apparent digestibility of CP among the three groups(P>0.05).The apparent digestibility of EE and Ash in trial group II was significantly higher than that in trial group I and control group(P<0.05),and the apparent digestibility of EE and Ash in trial group II was significantly higher than that in control group(P<0.05).The apparent digestibility of CF in trial group II was significantly higher than that in trial group I and control group(P<0.05).(3)At days 45-74,the ADG of fattened goat in MFFDG group was significantly higher than that in MFWDG group(P<0.05),and the F/G in MFFDG group was significantly lower than that in MFFDG group(P<0.05),and there was no significant difference in ADFI between the two groups(P>0.05).There were no significant differences in slaughter rate,loin muscle area and GR between MFFDG group and MFWDG group(P>0.05).The heart weight of MFFDG group was significantly higher than that of MFWDG group(P<0.05),but there were no significant differences in head,foot,liver,spleen,lung,kidney and internal organ indexes(P>0.05).There were no significant differences in carcass p H,meat color and conventional nutrients in meat between MFFDG and MFWDG groups(P>0.05).The content of myristic acid in longissimus dorsi muscle in MFFDG group was significantly higher than that in MFWDG group(P<0.05),but there were no significant differences in the contents of other fatty acids and amino acids in longissimus dorsi muscle between MFFDG and MFWDG group(P>0.05).In conclusion,appropriate probiotics combination and process parameters play a crucial role in the production of high-quality MFFDG feed in SSF workshop,and the selected probiotics combination and optimized process parameters are more conducive to the application in actual production,so as to improve the nutritional value and production efficiency of MFFDG feed.MFFDG can effectively improve the growth performance and nutrient apparent digestibility of weaned lambs,but does not reduce the slaughter performance and meat quality of fattening sheep.Therefore,this study provides an important reference for the efficient utilization of distiller’s grains and the improvement of comprehensive benefit of goat industry.