运输后禁食与非禁食对肉兔应激水平、肉品质和行为的影响

本试验以伊拉肉兔为研究对象，探究肉兔运输后在禁食与非禁食条件下对其应激水平、肉品质和行为的影响，探索合理的肉兔运输后的处理方式。试验选取80只体重相近（（2.5±0.5） kg）的伊拉公兔，随机分为8个组：对照组、运输后0 h组、非禁食6 h组、非禁食24 h、禁食6 h组、禁食24 h组、禁食行为观察组和非禁食行为观察组（做行为观察，不屠宰）。预试期为7 d，正式期的运输时间为2 h。结果发现，在血清生化测定中，和对照组相比，运输后0 h组血清ALT、AST、TG、Glu、CK、LDH水平无显著变化（P>0.05），而运输后0 h组血清TP浓度显著下降，皮质醇浓度显著上升（P<0.05）。非禁食24 h组血糖水平高于禁食24 h组（P<0.05）、血清CK浓度低于禁食24 h组（P<0.01），非禁食6 h的LDH水平低于禁食6 h组（P<0.05）。在肉品质测定中，运输后0 h时肌肉pH显著上升（P<0.05），肌肉L^*、a^*水平显著下降（P<0.05），而非禁食24 h组的L^*、a^*和b^*值显著高于禁食24 h组。而禁食组与非禁食组的肌肉pH、失水率、蒸煮损失率和剪切力等无显著差异（P>0.05）。在基因表达方面，运输后0 h时JNK、Caspase-3的mRNA水平显著上升（P<0.05）。非禁食相比于禁食降低了JNK mRNA相对表达量（P<0.05），对Caspase-3水平无显著影响（P>0.05）。在行为学方面，非禁食相比于禁食降低了肉兔的食粪行为（P<0.05），对于肉兔刻板行为改变不明显（P>0.05）。本研究提示，在运输后静养期间，24 h非禁食能一定程度降低肉兔的应激、减少机体损伤、改善兔肉品质，有利于提高肉兔的福利水平。

Effects of Non-Fasting and Fasting before Slaughter on Stress Level,Meat Quality and Behavior of Meat Rabbits after Transportation

Hyla meat rabbits were taken in this experiment to study the effects of fasting and non-fasting on the stress level, meat quality and behaviors, and to explore a reasonable post-treatment method for meat rabbits after transportation. Eighty male Hyla rabbits with weight of (2.5±0.5) kg were chosed and randomly divided into 8 groups:control group, 0 h after transportation group, non-fasting 6 h group, non-fasting 24 h, fasting 6 h group, fasting 24 h group, fasting behavior observation group and non-fasting behavior observation group (behavior observation without slaughter). The pre-trial period was 7 days, and the transportation in formal experiment lasted for 2 hours. The results were as follows:Compared with the control group, the serum levels of ALT, AST, TG, Glu, CK and LDH had no significant changes at 0 h after transportation (P>0.05), but the serum TP concentration decreased and the cortisol concentration increased significantly after transportation (P<0.05). The levels of serum glucose were higher, but CK activities were lower in non-fasting 24 h group than in fasting 24 h group (P<0.05), and the levels of LDH activities in non-fasting 6 h group were lower than those in fasting 6 h group (P<0.05). In the determination of meat quality, the muscle pH increased significantly at 0 h after transportation (P<0.05), and the muscle L^* and a^* levels decreased significantly (P<0.05). The L^*, a^* and b^* values of non-fasting 24 h group were significantly higher than those of fasting 24 h group. There was no significant difference in muscle pH, water loss rate, cooking loss rate or shear force between fasting group and non-fasting group (P>0.05). In terms of gene expression, JNK and Caspase-3 levels increased significantly at 0 h after transportation (P<0.05). Compared with fasting, non-fasting decreased the relative expression of JNK mRNA (P<0.05), but had no significant effect on Caspase-3 level (P>0.05). In the aspect of behaviors, compared with fasting, non-fasting only reduced the caecotrophy behavior (P<0.05), but did not change the stereotyped behaviors of meat rabbits significantly (P>0.05). Non-fasting for 24 hours during lairage period after transportation can improve the meat quality to a certain extent, reduce stress and body damage, and improve the welfare levels of meat rabbits.