摘要
本试验旨在研究饲粮不同消化能(DE)和标准回肠可消化赖氨酸(SID Lys)水平对育肥后期川藏黑猪生长性能、养分表观消化率、血清生化指标、胴体性状、肉品质及肌肉蛋白质代谢等的影响。试验采用2(2个饲粮DE水平:12.97和13.39 MJ/kg)×3(3个饲粮SID Lys水平:0.55%、0.63%和0.70%)因素设计,选择90头初始体重为(89.65±8.75)kg的川藏黑猪,随机分为6组,每组5个重复,每个重复3头猪。试验期31 d,第28~31天采用内源指示剂法进行消化试验。结果表明:1)饲粮SID Lys水平对生长性能和养分表观消化率均无显著影响(P>0.05);提高饲粮DE水平可显著提高平均日增重(ADG)及粗脂肪和总能表观消化率(P<0.05),并显著降低料重比(F/G)(P<0.05)。2)血清尿素氮含量随饲粮SID Lys水平的升高呈先降后升的变化(P<0.05);提高饲粮DE水平可显著降低血清谷丙转氨酶活性(P<0.05),而显著提高血清甘油三酯含量(P<0.05)。3)饲粮DE和SID Lys水平对胴体性状无显著影响(P>0.05),但背膘厚度随饲粮SID Lys水平的升高呈先升后降的变化趋势(P=0.056)。4)屠宰后45 min背最长肌肉色亮度值随饲粮SID Lys水平的升高而降低(P<0.05),大理石纹评分随饲粮DE水平的升高而提高(P<0.05)。5)背最长肌蛋白激酶B(AKT)和肌肉环指蛋白1(MuRF1)mRNA相对表达水平随饲粮DE水平的升高而升高(P<0.05);饲粮DE与SID Lys水平对背最长肌哺乳动物雷帕霉素靶蛋白(mTOR)mRNA相对表达水平存在显著交互效应(P<0.05):当DE为12.97 MJ/kg时,mTOR mRNA相对表达水平随饲粮SID Lys水平的升高而降低;当DE为13.39 MJ/kg时,mTOR mRNA相对表达水平随饲粮SID Lys水平的升高而升高。综上所述,在本试验条件下,饲粮DE和SID Lys水平对育肥后期川藏黑猪生长性能、养分表观消化率、血清生化指标以及肌肉蛋白质代谢等均产生不同程度的影响。以ADG、F/G和血清生化指标等作为综合评判标识,90~115 kg阶段川藏黑猪饲粮适宜DE和SID Lys水平分别为13.39 MJ/kg和0.63%。
This experiment aimed to investigate the effects of different dietary digestible energy(DE)and standardized ileal digestible lysine(SID Lys)levels on growth performance,nutrient apparent digestibility,serum biochemical indices,carcass traits,meat quality,and muscle protein metabolism of late finishing Chuanzang black pigs.The experiment employed a 2×3 factorial design,with two DE levels(12.97 MJ/kg and 13.39 MJ/kg)and three SID Lys levels(0.55%,0.63%and 0.70%).A total of 90 Chuanzang black pigs,with an initial body weight of(89.65±8.75)kg,were randomly assigned into 6 groups,with 5 replicates per group and 3 pigs per replicate.The experiment lasted for 31 days,and a digestion trial was conducted from days 28 to 31 using the endogenous indicator method.The results showed as follows:1)dietary SID Lys level had no significant effects on the growth performance and nutrient apparent digestibility(P>0.05).However,increasing dietary DE level significantly improved the average daily gain(ADG)and apparent digestibilities of ether extract and gross energy(P<0.05),while significantly reduced the feed-to-gain ratio(F/G)(P<0.05).2)The serum urea nitrogen content showed decrease and then increase with dietary SID Lys level increasing(P<0.05).Increasing dietary DE level significantly reduced the serum alanine aminotransferase activity(P<0.05),while significantly increased the serum triglyceride content(P<0.05).3)Dietary DE and SID Lys levels did not significantly impact carcass traits(P>0.05);however,the backfat thickness exhibited a trend of initial increase followed by decrease with dietary SID Lys level increasing(P=0.056).4)The lightness value in longissimus dorsi muscle was decreased at 45 minutes post-slaughter with dietary SID Lys level increasing(P<0.05),and the marbling score was increased with dietary DE level increasing(P<0.05).5)The mRNA relative expression levels of protein kinase B(AKT)and muscle RING-finger protein 1(MuRF1)in longissimus dorsi muscle were upregulated with dietary DE level increasing(P<0.05).Furthermore,a significant interaction between dietary DE and SID Lys levels was observed for mammalian target of rapamycin(mTOR)mRNA relative expression level in longissimus dorsi muscle(P<0.05):when DE was 12.97 MJ/kg,the mTOR mRNA relative expression level was decreased with dietary SID Lys level increasing;however,at 13.39 MJ/kg DE,the mTOR mRNA relative expression level was increased with dietary SID Lys level increasing.The results indicate that dietary DE and SID Lys levels exert varying degrees of influence on growth performance,nutrient apparent digestibility,serum biochemical indices,and muscle protein metabolism of late finishing Chuanzang black pigs.Based on comprehensive evaluation indicators including ADG,F/G,and serum biochemical indices,et al,the optimal dietary DE and SID Lys levels for Chuanzang black pigs weighing 90 to 115 kg are 13.39 MJ/kg and 0.63%,respectively.
作者
邵凯文
陈国
蒲俊宁
陈代文
余冰
SHAO Kaiwen;CHEN Guo;PU Junning;CHEN Daiwen;YU Bing(Key Laboratory for Animal Disease-Resistance Nutrition of Ministry of Education,Institute of Animal Nutrition,Sichuan Agricultural University,Chengdu 611130,China)
出处
《动物营养学报》
北大核心
2026年第2期979-993,共15页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
四川省重点研发项目“主要畜禽新品种关键养殖技术创新与应用(育种攻关项目)”(2021YFYZ0008)。
