Study on nutrient degradation rate of donkey main concentrate feed by three steps in vitro

YANG Qing-miao; LIU Chang; ZHAO Yan-li; GUO Yong-mei; GUO Xiao-yu; YAN Su-mei

doi:10.13557/j.cnki.issn1002-2813.2023.16.020

Abstract：The study was to simulate in vitro gastrointestinal environment through in vitro three-step method,namely pepsin-trypsin-cecum liquid method,to study in vitro degradation rate of donkey common concentrate raw materials in gastrointestinal tract,so as to evaluate the nutritional value of donkey common concentrate raw materials.Concentrate feed materials widely used in donkey breeding and production were selected,including nine kinds of energy feed and eight kinds of protein feed.After digestion in the simulated stomach environment for 1 h and in the small intestine for 24 h,they were cultured in vitro for 24 h,cecal fluid was collected,and the degradation rate of refined feed raw materials was measured.The results showed that the nutritional value of corn,pressed corn and wheat was higher,corn bran and soybean hull were lower,and wheat bran,corn germ meal,inferior flour and sprayed corn hull were in the middle of in vitro degradation rate of donkeys to energy feed.Among in vitro degradability of protein feed in donkey stomach-intestine-cecum,corn gluten meal,soybean meal,DDGS,extruded soybean and double-low rapeseed meal had higher nutritional value,especially corn gluten meal,rapeseed meal and cottonseed meal had lower nutritional value,and whole cottonseed had the lowest nutritional value.DM,OM and CP in energy and protein feeds contributed more than 70%of nutrients in stomach-intestine(prececal).However,DM and OM of corn gluten meal,corn bran and soybean hull were lower,and CP of corn gluten meal was also lower,which was 39.4%.The experiment indicates that in the energy feed,in vitro degradation rate and DE of nutrients of corn,pressed corn and wheat are higher.The corn husk and soybean husk are lower,and other energy feeds are in the middle.The in vitro degradation rate and DE of nutrients in soybean meal,DDGS,extruded soybean and double-low rapeseed meal are higher,especially in soybean meal.