苜蓿粉碎粒度对生长肉兔屠宰性能、血清生化指标和胃肠道厚度的影响OA

This study aimed to systematically evaluate the effects of alfalfa particle size on slaughter perfor-mance,serum biochemical parameters,and gastrointestinal tissue structure in growing meat rabbits.A total of 120 weaned New Zealand rabbits aged(35±2)days were randomly allocated into four groups and fed diets containing alfalfa meal with particle sizes of 2 500 µm,1 000 µm,100 µm,and 10 µm,respectively.The groups were designated as the group 2 500,group 1 000,group 100,and group 10.The experimental period lasted 42 days.The results showed that alfalfa particle size had no significant impact on slaughter perfor-mance(P>0.05).However,the kidney index in the 100 and 10 groups was significantly higher than that in the control group(P<0.01).Serum urea concentration was significantly lower in the 100 group than in the other three groups(P<0.05),while glucose concentration was significantly higher in the 1 000 group than in the 10 group(P<0.05).Alkaline phosphatase activ-ity increased progressively with decreasing par-ticle size(P<0.01).For gastrointestinal structure,jejunal wall thickness was significantly greater in the control group than in the 10 group(P<0.05),while ileal wall thickness was significantly greater in the 100 group than in the control(P<0.01).The cecal mucosa was thickest in the 1 000 group,and the gastric mucosa was significantly thicker in the 100 group than in the other groups(P<0.01).In summary,although ultrafine grinding of alfalfa enhanced the digestive and metabolic functions of meat rabbits,it also caused certain structural damage to the gastrointes-tinal tract and did not improve slaughter performance.Therefore,excessively fine alfalfa particle sizes are not recommended in rabbit feed processing.A particle size range of 100-1 000 µm is considered optimal for achieving balanced growth performance and production efficiency.