Ahiwe Emmanuel Uchenna, Abdallh Medani Eldow, Chang'a Edwin Peter, Omede Apeh Akwu, Al-Qahtani Mohammed, Gausi Harriet, Graham Hadden, Iji Paul Ade
School of Environmental and Rural Sciences, University of New England, Armidale NSW, 2351 Australia.
Department of Animal Science and Technology, Federal University of Technology, Owerri, PMB 1526, Imo State, Nigeria.
Asian-Australas J Anim Sci. 2020 Apr;33(4):579-587. doi: 10.5713/ajas.19.0220. Epub 2019 Jul 1.
This study evaluated the effect of yeast products on growth performance, visceral organ weights, endogenous enzyme activities, ileal nutrient digestibility and meat yield of broiler chickens fed diets containing autolyzed whole yeast (WY) and yeast cell walls (YCW) at varying levels of inclusion.
Nine dietary treatments consisting of WY or YCW included at 0.5, 1.0, 1.5, or 2.0 g/kg diet and a control diet without yeast supplementation was used in the experiment. Each of the nine treatments was replicated six times with nine birds per replicate. Birds were housed in cages, in climate-controlled rooms and fed starter, grower and finisher diets.
There was an improvement (p<0.05) in body weight gain and feed conversion ratio on d 10, 24, and 35 for birds fed 1.0 to 2.0 g/kg WY or YCW diet. Small intestine weight was heavier on d 10 and 24 for birds on higher levels of WY and YCW compared to the control group. On d 10 and 24, there was a significant increase (p<0.05) in tissue protein content and pancreatic enzyme activities (trypsin and chymotrypsin) of birds on 1.5 to 2.0 g/kg WY and YCW diets compared to the control group. Compared to the control group, birds on WY (2.0 g/kg diet) and YCW (at 1.5 and 2.0 g/kg diet) had better (p<0.05) protein digestibility on d 24. On d 35, there was significant improvement (p<0.05) in percentage of carcass, absolute and relative breast weight for broiler chickens fed WY and YCW mostly at 2 g/kg diet compared to birds on the control diet.
Supplementation of diets with autolyzed WY and YCW products especially at 1.5 to 2.0 g/kg diet improved broiler chicken performance and meat yield through their positive effects on ileal protein digestibility and pancreatic enzyme activities.
本研究评估了酵母产品对饲喂含不同添加水平自溶全酵母（WY）和酵母细胞壁（YCW）日粮的肉鸡生长性能、内脏器官重量、内源酶活性、回肠养分消化率及产肉量的影响。
实验采用九种日粮处理，其中WY或YCW的添加量分别为0.5、1.0、1.5或2.0 g/kg日粮，还有一种不添加酵母的对照日粮。九种处理各重复六次，每个重复有九只鸡。鸡饲养在笼中，置于气候控制的房间内，饲喂开食料、生长料和育肥料。
饲喂1.0至2.0 g/kg WY或YCW日粮的鸡在第10、24和35天的体重增加和饲料转化率有所改善（p<0.05）。与对照组相比，较高水平WY和YCW日粮组的鸡在第10和24天小肠重量更重。在第10和24天，与对照组相比，饲喂1.5至2.0 g/kg WY和YCW日粮的鸡的组织蛋白含量和胰腺酶活性（胰蛋白酶和糜蛋白酶）显著增加（p<0.05）。与对照组相比，饲喂WY（2.0 g/kg日粮）和YCW（1.5和2.0 g/kg日粮）的鸡在第24天的蛋白质消化率更好（p<0.05）。在第35天，与对照组相比，大多数饲喂2 g/kg WY和YCW日粮的肉鸡的胴体百分比、绝对和相对胸肌重量有显著改善（p<0.05）。
日粮中添加自溶WY和YCW产品，尤其是添加量为1.5至2.0 g/kg时，通过对回肠蛋白质消化率和胰腺酶活性产生积极影响，改善了肉鸡的生长性能和产肉量。
