As there is a possibility that Se influences the growth of animals via thyroid hormone metabolism, the following three experiments were undertaken in order to determine the effects of dietary Se on growth, skeletal muscle protein turnover and thyroid hormone status in broiler chickens. Broiler chickens were raised on a Se-deficient diet until 12 d of age and then used for the experiments. In Experiment 1, twenty-eight birds were randomly assigned to four groups and fed purified diets with the following amounts of Se supplementation: 0.0, 0.1, 0.3, and 0.5mg Se/kg diet. Dietary Se supplementation significantly increased plasma 3,5,3'-triiodothyronine (T3) concentration and improved growth, while plasma thyroxine (T4) concentration was decreased. In Experiment 2, twenty-eighy birds were assigned to four groups and fed either a Se-deficient diet or a Se-supplemented diet (0.3 mg Se/kg diet) with or without the supplementation of iopanoic acid, a specific inhibitor of 5'-deiodinase (5 mg/kg diet). The growth was promoted and feed efficiency was improved by dietary Se supplementation as was also observed in Experiment 1. However, this effect of Se and inhibited by iopanoic acid. In Experiment 3, birds were fed on the following diets to show that Se influences growth of birds via thyroid hormone metabolism; Se-deficient diet, Se-supplemented diets (0.1 and 0.3 mg/kg) and T3 supplemented diets (0.1 and 0.3 mg/kg diet). Lower dietary T3 supplementation (0.1 mg/kg diet) resulted in growth promotion similar to Se supplementation, while higher level of T3 caused growth depression. Furthermore, it was observed that the rate of skeletal muscle protein breakdown tended to be increased by Se similarly to the effect of T3. In conclusion, it was shown in the present study that Se deficiency depresses growth of broilers by inhibiting hepatic 5'-deiodinase activity which causes lower plasma T3 concentration.

对18个饲料用水稻样品的稻谷和糙米的常规营养成分、氨基酸组成和有效能值进行了分析和测定。稻谷和糙米含蛋白质为（8.85±1.23）%，（10.35±1.33）%，含总能分别为（15.83±0.28）MJ/kg，（15.95±0.20）MJ/kg，含消化能10.28MJ/kg和13.48MJ/kg。稻谷的养分消化率明显低于糙米的相应值。主要是由于稻谷含粗纤维8.94%，而糙米的相应值为1.19%。稻谷和糙米分别含赖氨酸0.29%和0.44%， 蛋氨酸0.10%和0.18%， 苏氨酸0.26%和0.30%。用作猪饲料时，赖氨酸是第一限制性氨基酸，苏氨酸是第二限制性氨基酸，异亮氨酸是第三限制性氨基酸。

为科学利用稻米和糙米作畜禽饲料，对早灿稻稻谷和糙米的猪消化能、糙米的鸡代谢能、稻谷和糙米的鸭代谢能为10.70±0.33MJ/kg，鸭表现代谢能为14.48±0.21MJ/kg，真代谢能为15.02±0.21MJ/kg。

分析了18个不同早籼稻品种在相同栽培条件下的稻谷与糙米的各种饲料营养成分及这些品种的农艺性状，结果表明，不同早籼稻品种稻谷与糙米的各种营养成分存在明显的品种间差异，其中以早籼稻品种稻谷与糙米的粗蛋白含量的品种间差异最大。18个早籼稻品种糙米的粗灰分、粗纤维与钙的平均含量比其稻谷的平均含量分别低2.45%，7.75%与0.009%；而18个早籼稻品种糙米的干物质、总能、粗蛋白、粗脂肪与磷的平均含量比其稻谷的平均含量分别高0.15%，0.09MJ/kg，1.35%，2.04%与0.01%。可见早籼稻糙米比早籼稻稻谷具有更高的营养价值，与玉米的营养价值相当。18个早籼稻品种产量及产量性状与其营养成分大都呈负相关关系，因此水稻遗传育种只有采用现代生物技术，打破这种产量与品质的负相关连锁，同时发掘新的种质资源，才能达到培育既高产又优质的早籼稻品种的育种目标。

通过蛋白质溶解度（PS）指标和体外透析管法测定了不同热处理对脱毒桐饼（粕）蛋白质品质的影响。结果表明：①3种脱毒桐饼（粕）的蛋白质体外消失率（PDIV）分别为（35.63±3.26）%（I）、（43.72±5.54）%（Ⅱ）、（34.03土l.30）%（Ⅲ），经单因素方差分析，三者之间无显著性差异（P>0.05）。②干热处理时。处理时间和处理温度均对其PS有显著影响（P<0.01）。即在处理时间不变的条件下，随着处理温度的升高，脱毒桐饼（粕）PS急剧下降。并且随着PS的降低，其PDIV也有降低的趋势；而当温度一定时，随着处理时间的延长。PS的下降趋势较为缓和。③湿热处理时，同一处理时间内，压力对脱毒捐饼（粕）蛋白质品质影响较小；而在一定压力条件下，随着处理时间的延长，其PS随之降低，显著影响脱毒桐饼（粕）蛋白质品质（P<0.01），并且随着脱毒桐饼（粕）PS的降低。其PDIV也有降低的趋势，两者之间的回归方程为y=2.84 x-28.10（r=0.889，y为脱毒桐饼（粕）PDIV，x为脱毒桐饼（粕）PS）。