肉鸡和大鼠磷代谢调控的差异比较研究

Comparative Studies on Phosphorus Metabolism in Chicken and Rat

通过对肉鸡和大鼠的饲喂试验,研究日粮不同磷水平对肉鸡和大鼠血磷,血钙以及肠道NaPi-ⅡbmRNA表达的影响。试验一,选择体重约1.5kg60日龄的三黄肉鸡40只,随机分为4个处理组,日粮总磷水平为0.4%、0.6%、0.8%、1.0%,每组5个重复,每个重复2只鸡。试验二,选用平均体重为18～22g,21日龄的雄性昆明大白鼠120只,随机分成4个处理组,日粮总磷水平依次为0.2%、0.4%、0.6%、0.8%,每组5个重复,每重复6只大白鼠。结果表明,随着日粮总磷水平的提高,鸡和大鼠血清磷的含量都呈上升趋势,在日粮磷水平为0.4%时血清磷最低,1.0%时最高,且两者0.4%与0.6%、0.8%和1.0%磷水平之间皆差异极显著(P<0.01)。低磷提高了小肠中NaPi-ⅡbmRNA的表达,高磷抑制小肠中NaPi-ⅡbmRNA的表达;不同磷水平对不同动物不同的组织部位中NaPi-ⅡbmRNA影响不同,大鼠和肉鸡空肠均随着日粮磷水平的提高NaPi-ⅡbmRNA表达量降低,回肠和十二指肠内未出现明显变化趋势。

In this paper, comparative studied on phosphorus metabolism in chicken and rats to further understand the molecular mechanism of phosphorus uptake and regulation of factors, and provide a reasonable scientific basis on dietary phosphorus adding. In Exp.1, studied the effects of diverse dietary phosphorus on the serum phosphorus and calcium levels. 40 chicken evaluated 60 day old broilers with an average initial weight of about 1.5 kg were allotted to four treatments randomly, levels of dietary phosphorus were 0.4%, 0.6%, 0.8% and 1.0% （all with calcium： phosphorus rations of 2：1）, group 0.6% was the matched group, each treatments had five replicates of two broilers （in the same metabolism cage）. In Exp.2, studied the effects of diverse dietary phosphorus on the serum phosphorus and calcium levels. 120 male Kunming-rats evaluated 21 day old broilers with an average initial weight of about 18-22 g were allotted to four treatments randomly, levels of dietary phosphorus were 0.2%, 0.4%, 0.6% and 0.8% （all with calcium： phosphorus rations of 2：1）, group 0.6% was the matched group, the experiment lasted for 7 days. The results showed that compareing the chicken and rats serum phosphoru levels corresponding to 4 dietary phosphoru levels＇ chicken and rats serum phosphorus levels were up with increased levels of dietary phosphorus,the lowest serum phosphorus in 0.4% dietary, the highest in 1.0% dietary, and between 0.4% and 0.6%, 0.8% and 1.0% phosphorus levels were significantly different （P〈0.01）. High phosphorus inhibit NaPi-It b mRNA expression and low Phosphorus increased NaPi- It b mRNA expression in the small intestine; The NaPi-Ⅱ b mRNA expression on different tissues in different animals was different, The NaPi-Ⅱb mRNA expression on jejunum of rats and chicken were decreased with the level of dietary phosphorus increaded, ileum and duodenum was no obvious trend.