二世代母鸡血浆VLDL浓度双向选择对蛋组成性状的影响

以雅发褐壳蛋鸡为素材,在一世代双向选择的基础上,依据血浆极低密度脂蛋白(VLDL)浓度对腹脂性状继续进行双向选择,比较高、低脂系蛋组成性状之间的差异,并研究二世代母鸡中、后期血浆VLDL浓度与蛋组成性状的相关程度。结果表明：二世代双向选择系母鸡间40周龄蛋黄重、蛋黄蛋白比例及60周龄蛋黄蛋白比例差异显著。血浆VLDL浓度与高、低脂系的蛋黄重、蛋黄比例、蛋黄蛋白比例呈显著正表型相关和中等程度正遗传相关,说明依据血浆VLDL浓度的低向选择可使蛋黄重、蛋黄比例、蛋黄蛋白比例降低。     

吡啶羧酸铬对育成期笼养蛋鸭生长性能和血液生化指标的影响

试验旨在研究饲粮铬水平对育成期笼养蛋鸭生长性能、血液生化指标的影响。试验采用单因素完全随机分组设计,选择健康28日龄金定蛋鸭180只,随机分成5组,每组6个重复,每个重复6只鸭。对照组(Ⅰ组)饲喂玉米-豆粕型基础饲粮,试验组(Ⅱ～Ⅴ组)分别在基础饲粮中添加0.15、0.30、0.45、0.60 mg/kg铬(吡啶羧酸铬),试验期6周。结果表明:①在饲粮中添加铬(吡啶羧酸铬)对笼养蛋鸭的日增重影响差异显著(P<0.05),但对采食量和料重比影响差异不显著(P>0.05);②一定量的铬(吡啶羧酸铬)对笼养蛋鸭的血糖、总胆固醇、甘油三酯产生显著影响(P<0.05),并促进了血清总蛋白、白蛋白的提高,同时显著降低了血清尿素氮的含量(P<0.05)。最终通过二次曲线回归方程对添加量和测定指标结果进行回归分析,得出结论:铬(吡啶羧酸铬)在育成期笼养蛋鸭饲粮中最适宜的添加量为0.297 0～0.422 5 mg/kg。     

Winter pairs of ruddy shelducks at Lashihai Lake,southwest China

It has been suggested that pairing behavior during winter in migratory ducks represents a trade‐off between costs (defense of the female) and benefits (early access to females). To investigate the benefits and costs for both sexes in wintering pairs of ruddy shelducks (Tadorna ferruginea), we compared time budgets for paired males and females, and surveyed the sex ratio of the birds wintering at Lashihai Lake, southwest China. The behavior of the paired ruddy shelducks was monitored for 5 activity types: feeding, resting (including sleeping), preening, drinking and warning. Feeding was the most dominant activity. The feeding time of both sexes increased as the winter season progressed. However, the paired females always spent significantly more time feeding and less time warning than the paired males. Paired ruddy shelducks had access to better feeding grounds than unpaired individuals, resulting in a food benefit for paired individuals over single individuals. Because the sex ratio of the wintering population was strongly male biased (M:F = 1.44:1.00), the paired male also gained the benefit of accessing a female in advance of the breeding season.     

Effect of sequential feeding using whole cereal grains during finishing period in male mule ducks (Carina moschata × Anas platyrinchos)

The feeding of waterfowl for fatty liver production is largely based on the use of completely pelleted feed. To reduce both the economic and environmental costs caused by transport and processing of feed and to respond to consumer demands for natural feeding systems, the use of whole grains has increased recently. The aim of this trial was to study the influence of 1) sequential feeding based on cereal grain and 2) cereal type (corn or triticale) during the finishing period on performance traits in male mule ducks. Present results suggest that a sequential feeding system modifies feeding behavior, growth, and body traits, and reduces feed intake during the finishing period (−6 and −10% for corn and triticale, respectively), but has no effect on performance during the overfeeding period. This system offers interesting prospects for a more sustainable rearing method, and the use of locally grown grains could reduce both the economic and environmental impacts of duck feeding.     

低温环境下饲粮硒添加水平对初产蛋鸭生殖器官发育及相关激素分泌的影响

本试验旨在研究低温(1 ～7℃)环境下饲粮硒(Se)添加水平对产蛋初期(120～155日龄)蛋鸭生殖器官发育及相关激素分泌的影响.试验选用120日龄金定鸭(母)216只,随机分为6组,每组6个重复,每个重复6只鸭.对照组饲喂玉米-豆粕型基础饲粮,试验组分别在基础饲粮中添加0.08、0.12、0.20、0.41、0.71...     

低温环境下饲粮核黄素添加水平对蛋鸭生长发育、免疫器官及抗氧化功能的影响

本试验旨在研究低温环境下饲粮核黄素添加水平对蛋鸭生长发育、免疫器官及抗氧化功能的影响.试验采用两因素有重复完全交叉设计,温度设2个水平[适温(18±1)℃,T1；低温(2±1)℃,T2]；核黄素设3个水平,在基础饲粮中分别添加4、16、32 mg/kg核黄素.选用12周龄健康的金定鸭(母)144只,随机分成6个处理,每...     

肉鸭蛋白质营养研究进展

文章综述了肉鸭蛋白质(氨基酸)营养研究进展。分析认为,提高肉鸭饲粮蛋白在体内的利用与沉积效率是提高饲料转化效率的主要途径;饲粮适宜的蛋白质(氨基酸)水平、能蛋比和理想蛋白氨基酸模式对于充分发挥肉鸭的生长潜力非常必要。     

鸭乙型肝炎病毒的致病性及致癌性研究──鸭乙型肝炎病毒表面抗原的纯化

应用氯化铭密度梯度离心技术，结合Ｄｏｔ－ＥＬＩＳＡ试验、￣（３２）Ｐ标记的鸭乙型肝炎病毒（ＤＨＢＶ）ＤＮＡ探针进行斑点杂交试验，从ＤＨＢＶ阳性的启东鸭血清中分离得到高纯度的ＤＨＢｓＡｇ颗粒，直径范围４０～６０ｎｍ，在ＣｓＣｌ溶液中的浮密度为１．１５ｋｇ／Ｌ，大多数呈１０ｎｍ厚的空心结构，形态不规则，近似球形，部分颗粒表面有凹陷结构，少数颗粒表面出现缺刻。以纯化的ＤＨＢｓＡｓ免疫新西兰大白兔，制备了高度特异性的兔抗ＤＨＢｓ血清及其纯化的兔抗ＤＨＢｓＩｇＧ。     

稻鸭鱼种养模式的生态效应研究

对稻、鱼鸭种养模式的生态效益研究表明,稻十鸭十鱼田0cm～20cm土层温度升高,土壤昼夜温差增大,土壤有机质、全氮、磷、钾分别增加25.7％,25.8％, 39.2％,5.4％,速效N,P_2O_5,K_2O养分增大;水稻植株虫口量减少,病害轻。可增收鲜鱼1912.5kg/hm~2, 成鸭440.3kg/hm~2,水稻产量增加11.1％,生态指数EI—0.8542,属良性循环。