肉种鸡日粮能量水平对子代肉仔鸡脂肪沉积及其相关血液指标的影响

试验采用单因子试验设计,选用20周龄体重相近的爱拔益加(AA)肉种母鸡300羽,随机分为3组,每组5个重复,每个重复20羽。在产蛋率达到5%时进行能量处理,对照组饲喂玉米-豆粕型基础日粮,高能组、低能组日粮能量水平分别为对照组的120%、80%,各组均限饲且饲喂量相同。随机抽取300羽产蛋中期(40~42周龄)肉种鸡孵化后的1日龄公雏,试验分组与母代相同,自由采食、饮水,试验期为49 d。结果表明,①与对照组相比,高能组28日龄肝脂率、皮脂厚和49日龄腹脂率显著提高(P<0.05);随着母体日粮能量水平降低,28日龄和49日龄肉仔鸡胸肌、腿肌、肝脏总胆固醇含量呈现出降低趋势,但均无显著变化(P>0.05)。②与对照组相比,高能组28日龄血清三碘甲腺原氨酸(T3)和甲状腺素(T4)含量、49日龄血清高密度脂蛋白(HDL)含量显著降低(P<0.05),而49日龄血清甘油三酯(TG)、低密度脂蛋白(LDL)含量显著升高(P<0.05);低能组49日龄血清胆固醇(CHO)含量显著降低(P<0.05),血清T3含量显著升高(P<0.05)。结果提示,随着肉种鸡日粮能量水平的升高,子代血清T3、T4水平呈现降低趋势,肝脂蓄积逐渐增多,从而使血脂水平也逐渐升高。综合考虑,肉种鸡日粮能量水平低20%可能更有利于子代的生长发育。

Effect of dietary energy level of broiler breeders on fat deposition and blood indices of their offspring

A single factor design was adopted,and 300 AA broiler breeders(20-week-age) with similar body weight were randomly allocated to 3 treatments with 5 replicates of 20 broilers.The experiment was conducted when the laying rate reached 5%.The broilers in the control group were fed a corn-soybean meal basal diet,and those in high energy group and low energy group were fed diets with 120% and 80% energy level of the basal diet,respectively.During the trial period,feed intake in each group was restricted and set the same.Three hundred 1-day-old male broilers were hatched during the middle period(40-42 week-old) of maternal broilers and allocated into 3 groups.All of their offspring were provided feed and water ad libitum.The experiment period of offspring was 49 days.The results showed that,② The offspring in high energy group showed a higher liver fat rate,subcutaneous fat thickness at 28-day-old and abdominal fat rate at 49-day-old than those in the control group(P<0.05).With the maternal dietary energy level decreased,total cholesterol in breast,thigh and liver of offspring trended to be reduced(P>0.05).②The contents of triiodothyronine(T 3) and thyroxine(T 4) at 28-day-old,high density lipoproteins(HDL) at 49-day-old in serum of offspring in high energy group were found to be lower than those in the control group(P<0.05),whereas triglyceride(TG) and low density lipoproteins(LDL) at 49-day-old were significantly elevated(P<0.05).Compared with the control group,T 3 content in low energy group was higher,but the cholesterol(CHO) showed an opposite trend(P<0.05).In conclusion,the increase of maternal dietary energy level brought detrimental effects on serum T 3 and T 4 of offspring.Furthermore,fat deposition in liver of offspring was increased,leading to an increase of serum lipid content of offspring.Generally,the maternal diet with 20% energy restriction may be more beneficial to growth and development of offspring.