低温和硒对育雏期笼养蛋鸭生长性能及内分泌的影响

以1日龄蛋雏鸭为试验动物,采用2×3(温度×硒)重复实验设计,研究适温、低温环境下日粮中添加不同水平的硒(0.2、0.4、0.8mg.kg-1)对育雏期笼养蛋鸭生长性能、内分泌的影响。结果表明,低温显著降低试验各周及全期的日增重(P<0.05),并使料重比显著增加(P<0.05),低温使试验各周的日采食量显著增加(P<0.05),全期虽不显著但有增加趋势;添加0.4mg.kg-1的硒能最有效提高日增重并降低日采食量和料重比,但差异不显著。低温使血清T3水平显著升高(P<0.01),T4水平有升高的趋势。在适温和低温环境下提高硒水平使T3有降低趋势,T4先升高后降低,但总体有升高趋势。低温环境下,血清皮质醇浓度较适温环境略有升高,提高硒添加水平,可使血清皮质醇浓度有降低的趋势。综合试验结果可知,低温使蛋雏鸭的生长性能下降;低温环境下添加0.4mg.kg-1硒在改善生长性能、调节内分泌等方面较其它添加水平作用更明显,能在一定程度上减缓低温对育雏的影响。

Effects of cool temperature and different selenium levels on the performance and incretion activity of ducklings in cages

The experiment took 1-day-old ducklings as experimental animal, applied experimental design of 2×3 factors(temperature×selenium) to determine the effects of cool temperature and selenium at different levels (0.2, 0.4, 0.8 mg·kg-1) on the performance and incretion activity of ducklings in cages. The results showed that the cool temperature significantly decreased the daily gain of per week and the full time(P<0.05), significantly increased feed to gain ratio(P<0.05), significantly increased feed intake of per week(P<0.05), which has no significant increase in the full time but tended to rise. Selenium with 0.4 mg·kg-1 effectly increased the daily gain and decreased the feed intake and feed to gain ratio, but had no significant effect. The level of T3 in the cool temperature showed significant increase(P<0.01), and the level of T4 tended to increase. The level of T3 tended to decline, and the level of T4 firstly increased and then decreased but the tendency was upward in the cool temperature and normal temperature. In cool temperature, the content of cortisol tended to increase, but as the level of dietary selenium increased, it tended to downward. In conclusion, cool temperature decreased the per-formance of ducklings, the effects with 0.4 mg·kg-1 selenium level on the performance and incretion activity of ducklings were the best, which could reduce the effect of cool temperature on the performance of ducklings.