The Effect Of Cysteamine And Maternal Thyroid Hormone On The Avian Growth

Diets were supplemented with cysteamine to study on effects of this additive on growth of quails and the possible mechanisms. Thyroxine is one of the important neuroendocrine factors and has been found in breeding eggs. The study was aimed to investigate effects of maternal thyroxine on chicken embryos by administration of the hormone in vivo. The study has an important significance on breeding and production of poultry as well as having implications on investigating effects of maternal inner environment on offspring development.The effect of cysteamine on quail growth500 quails were allotted into three groups. Two treatment groups were fed 150mg/kg cysteamine or 300mg/kg cysteamine. After 14 days, compared with control, the body weights of quails in two treated groups were enhanced significantly; the feed intakes were decreased significantly; the serum T3 was enhanced significant in 150mg/kg cysteamine treated group; in both treated group there were in significantly increased tendency in serum T4 content; and there was no significant different for the thymus index, bursal index , NDV antibody levels and SOD, MDA content in serum among three groups.The effect of the thyroid hormone injected to eggs on the chicken embryo development 200 eggs were weighed and divided into control and treated group. The T3 was resolved by PBS , and 100 ul solution was injected in each egg. Those eggs were hatched. At 1 day, the chicken were weighed, blood and muscle were sampled. The results showed there was significantly difference on the body weight between two groups; the liver weight increased significant in male chicken group of treated group than that in control group (P=0.01) , and there was no difference between two group in female chicken group; the pectoris muscle weight was higher tendency in female chicken of treated group than that in control group (P=0.07); there were an increased tendency of the total amino acid content in serum of male chicken group than that in control group (P=0.07) , but here was no difference in female chicken group; there was significant different of total amino acid content in male chicken muscle (P=0.003) , and there was similar tendency in female chicken (P=0.08) ; the thyroid hormone receptor gene expression was increased tendency in male chicken (P=0.11) , but there was no difference in female chicken group.