体外发酵法评价山桐子饼作为湖羊蛋白质饲料的可行性OA

This study aimed to evaluate the ruminal in vitro fermentation parameters of Idesia polycarpa cake and soybean meal in Hu sheep using an in vitro fermentation technique.Rumen fluid was collected from six male Hu sheep[(31.27±0.68)kg]for in vitro fermentation.The trial included three treatments:a soybean meal group,an Idesia polycarpa cake group,and an Idesia polycarpa cake-urea group,with seven fermenta-tion modules per group.The fermentation sub-strates were 4 g of soybean meal and Idesia poly-carpa cake for the soybean meal group and the Idesia polycarpa cake group,respectively.The Idesia polycarpa cake-urea group received the same substrate as the Idesia polycarpa cake group supplemented with 1%slow-release urea.After 48 hours of fermentation,parameters including pH,ammonia nitrogen,microbial protein,in vitro dry matter degradability,and volatile fatty acid levels were determined.The results showed that:① no significant differences existed in pH and propionate levels among the 3 groups(P>0.05).② In vitro dry matter degradability,ammonia nitrogen,total volatile fatty acid,acetate,butyrate,acetate/propionate,or methane levels in the Idesia polycarpa cake group were significantly lower than those in the soybean meal group(P<0.05).③ Supplementation with slow-release urea signifi-cantly increased ammonia nitrogen concentration compared to the Idesia polycarpa cake group(P<0.05).In conclusion,the in vitro fermentation parameters indicate a lower nutritional value of Idesia polycarpa cake compared to soybean meal.However,it does not negatively affect ruminal microbial protein yield,demon-strating its potential as a protein feed for sheep.