摘要
选择初始体重约20.7 kg的长白×荣昌杂交猪72头,随机分为3组,研究日粮能量水平对肥育猪肌内脂肪含量的影响及其与脂肪酸合成酶和激素敏感脂酶mRNA表达的关系。日粮的消化能分别为11.75 MJ/kg(低能组)、13.05 MJ/kg(中能组)、14.36 MJ/kg(高能组)。试验猪体重达到100 kg时,进行屠宰。结果表明:①提高日粮能量水平,对猪的日增重、日采食量没有显著影响(P>0.05),但提高了饲料转化率(P<0.05),缩短了育肥时间(P<0.05),增加了背膘厚、外周脂肪和肌内脂肪含量(P<0.05);②14.36 MJ/kg的能量水平提高了背膘中脂肪酸合成酶mRNA的表达(P<0.05),降低了激素敏感脂酶mRNA的表达,从而增加了背膘中肌内脂肪酸合成酶与激素敏感脂酶mRNA的比值;③日粮能量水平与肌内脂肪含量、脂肪酸合成酶mRNA丰度以及脂肪酸合成酶与激素敏感脂酶mRNA的比值呈显著正相关(P<0.05),脂肪酸合成酶与激素敏感脂酶mRNA比值和肌内脂肪含量也呈显著正相关(P<0.05),激素敏感脂酶mRNA表达量与能量水平呈极显著负相关(P<0.01),与肌内脂肪含量呈显著负相关(P<0.05)。本研究表明,提高日粮能量水平能增加脂肪沉积;能量水平影响脂肪(尤其是肌内脂肪)沉积可能是通过调节脂肪酸合成酶和激素敏感脂酶两种酶mRNA表达量实现的,而不是单独调节其中之一实现的。
Seventy-two Landrace × Rongchang crossbred barrows, with initial body weight of 20. 7 kg, were allocated to three treatments to study the effect of energy levels of dietary on mRNA expression for the content of intramuscular fat and their association with fatty acid synthase （FAS） and hormone-sensitive lipase（HSL） at finishing stage. The digestible energy levels of dietary were 11.75, 13.05 and 14.36 MJ/kg, respectively. The pigs were slaughtered at 100 kg body weight. The results showed that： （1）There were no significant effects of energy density on average daily gain（ADG） and average daily feed intake（ADFI） （P〉0.05）, while feed conversion ratio was improved（P〈0.05）and the duration of finishing was shortened （P 〈 0.05） with energy density increasing. The percentage of external fat, backfat thickness and intramuscular fat were increased （P 〈 0.05） with increasing of energy density. （2）The dietary energy density of 14.36 MJ/kg improved the mRNA expression of FAS in backfat （P 〈 0.05） , decreased the mRNA expression of HSL （P 〈 0.05） and increased the ratio of mRNA of FAS to HSL （P〈 0.05） in both backfat and intramuscle. （3）There were significantly positive correlations （P 〈0.05） between energy levels and intramuscular fat, FAS mRNA and the ratio of mRNA of FAS to HSL, between the ratio of mRNA of FAS to HSL and intramuscular fat . However, the extremely significantly negative correlations （P 〈 0.01）were observed between HSL mRNA and dietary energy,significantly negative correlations （P 〈 0.05） were observed between HSL mRNA and intramuscular fat. This study indicated that higher energy level of dietary could increase fat deposition. Moreover, effects of dietary energy level on fat deposition, especially on intramuscular fat deposition, maybe modulate both the mRNA of FAS and HSL, not anyone of them.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2007年第9期934-941,共8页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
"973"国家重点基础研究发展计划项目(2004CB117503)
重庆市自然科学基金项目(2005BA1012)
关键词
能量
脂肪沉积
脂肪酸合成酶
激素敏感脂酶
生长育肥猪
energy
lipid deposition
fatty acid synthase
hormone-sensitive lipase
growing-finishing pigs
