Estimation of genetic parameters for racing speed at different distances in young and adult Spanish Trotter horses using the random regression model

A total of 71 522 records (from 3154 horses) with the times per kilometre (TPK), recorded in Spanish Trotter horses (individual races) from racing performances held from 1991 to 2007, were available for this study. The TPK values for the different age groups (young and adult horses) and different distances (1600–2700 m) were considered as different traits, and a bi character random regression model (RRM) was applied to estimate the (co)variance components throughout the trajectory of age groups and distances. The following effects were considered as fixed: the combination of hippodrome‐date of race (404 levels); sex of the animals (3 levels); type of start (2 levels) and a fixed regression of Legendre polynomials (order 2). Those considered as random effects were the random regression Legendre polynomial (order 1) for animals (9201 animals in the pedigree); the individual environment permanent (3154 animals with data) and the driver (n = 957 levels). The residual variance was considered as heterogeneous with two classes (ages). The heritability estimated by distance ranged from 0.12 to 0.34, with a different trajectory for the two age groups. Within each age group, the genetic correlations between adjacent distances were high (>0.90), but decreased when the differences between them were over 400 metres for both age groups. The genetic correlations for the same distance across the age groups ranged from 0.47 to 0.78. Accordingly, the analysed trait (TPK) can be considered as positive genetic correlated but as different traits along the trajectory of distance and age. Therefore, some re‐ranking should be expected in the breeding value of the horses at different characteristics of the racing. The use of RRM is recommended because it allows us to estimate the breeding value along the whole trajectory of race competition.     

高效液相色谱法测定4.5%氯氰菊酯乳油中两种异构体的含量

采用高效液相色谱法对4.5%氯氰菊酯乳油中高效cisB及transB的含量进行测定,该方法测定结果稳定,线性良好,重复性较高。     

中草药添加剂对育肥猪生长性能及血液生化指标的影响

将120头胎次、日龄相近,体质量在70kg左右的＂杜×长×大＂三元杂交猪随机分为4组,空白对照组只饲喂基础饲粮,西药组添加0.02%半胱胺,其他2组分别添加1%和0.5%的中草药添加剂。结果表明：在生长性能方面,2个中药组（B、C组）、半胱胺组（D组）的日增重分别比空白对照组（A组）提高了9.89%（P〈0.05）,4.42%（P〉0.05）和1.26%（P〉0.05）,料肉比分别比对照组降低了7.07%（P〈0.05）,4.49%（P〈0.05）和3.97%（P〈0.05）;添加中草药添加剂,对猪只肝肾功能无不良影响。     

高寒地区野生垂穗披碱草农艺性状及生产性能评价

对采自青海省不同海拔和不同地区的7份野生垂穗披碱草(Elymus nutans Griseb.)在西宁地区对其农艺性状及生产性能进行评价,为青藏高原地区筛选育种材料提供理论依据.结果表明:7份材料中采自海南州同德县高寒草甸海拔3201m的4号材料产草量最高,可作为饲草型牧草进行选育;采白果洛州玛多县高寒草原海拔4385m的1号材料表现出较好的综合生产性能和适应性,可作为饲草兼产籽型牧草进行选育.     

饲粮添加不同水平苜蓿粗多糖对蛋鸡生产性能和蛋品质的影响

本试验旨在研究饲粮添加不同水平苜蓿粗多糖对蛋鸡生产性能和蛋品质的影响。选取540只27周龄的海兰褐壳蛋鸡,随机分为6组,每组6个重复,每个重复15只鸡。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加250、500、1 000、2 000和4 000 mg/kg苜蓿粗多糖的试验饲粮。试验期24周。结果表明:与对照组相比,1)试验1~8周,500、2 000和4 000 mg/kg苜蓿粗多糖添加组产蛋率均显著提高(P0.05);试验9~16周、17~24周和1~24周,250、500、1 000和2 000 mg/kg苜蓿粗多糖添加组产蛋率显著提高(P0.05),料蛋比显著降低(P0.05),且在试验17~24周和1~24周,总产蛋重量显著提高(P0.05),而平均蛋重和采食量无显著差异(P0.05);2)250、500和1 000 mg/kg苜蓿粗多糖添加组在试验第6、8、12、16、20和24周蛋壳颜色显著加深(P0.05),且在试验第8、12、16周较4 000 mg/kg苜蓿粗多糖添加组蛋壳颜色亦显著加深(P0.05);3)2 000 mg/kg苜蓿粗多糖添加组在试验第6、20、24周蛋壳强度显著提高(P0.05);4)试验第8、12、16、20和24周,250、500、1 000和2 000mg/kg苜蓿粗多糖添加组蛋壳厚度显著增加(P0.05),且4 000 mg/kg苜蓿粗多糖添加组在试验第8、20、24周蛋壳厚度亦显著增加(P0.05);5)2 000 mg/kg苜蓿粗多糖添加组在试验第10、12和24周蛋白高度和哈夫单位显著提高(P0.05),且2 000 mg/kg苜蓿粗多糖添加组在试验第10和12周蛋白高度和哈夫单位显著高于250、1 000和4 000 mg/kg苜蓿粗多糖添加组(P0.05)。试验表明,产蛋期蛋鸡饲粮中添加适宜水平的苜蓿粗多糖可以显著提高蛋鸡生产性能,改善蛋品质,且推荐适宜添加水平为250 mg/kg。     

饲粮能量水平对德州驴生长性能、营养物质消化率及血清生化指标的影响

本研究旨在探讨饲粮能量水平对德州驴生长性能、营养物质消化率及血清生化指标的影响。试验选用健康的7～8月龄德州公驴36头,体重(123.9±5.0) kg,随机分为3个组,每组3个重复,每个重复4头驴。各组饲粮消化能水平分别为10.43 (低能组)、11.03 (中能组)和11.90 MJ/kg(高能组),粗蛋白质水平相近。预试期20 d,正试期40 d。结果表明：1)中能组和高能组的平均日增重显著高于低能组(P<0.05),且高能组的平均日增重显著高于中能组(P<0.05)。中能组和高能组的料重比显著低于低能组(P<0.05),且高能组的料重比显著低于中能组(P<0.05)。2)中能组和高能组的干物质、有机物和碳水化合物消化率显著高于低能组(P<0.05),且高能组的干物质、有机物和碳水化合物消化率显著高于中能组(P<0.05)。3)高能组的血清总蛋白、甘油三酯含量显著高于中能组和低能组(P<0.05)。中能组和高能组的血清白蛋白含量显著高于低能组(P<0.05),且高能组的血清白蛋白含量显著高于中能组(P<0.05)。中能组和高能...     

热应激条件下藿朴蒲苓散对育肥羔羊生长性能、消化性能和血清生化指标的影响

针对夏季绵羊遭受严重热应激现状,研究日粮中添加中草药组方(藿朴蒲苓散)对夏季育肥羔羊生长性能、消化性能、瘤胃发酵参数及血清生化指标的影响。选择200只体重相近、年龄一致的健康育肥公羔羊,随机分为4组,分别饲喂0%(对照组)、0.5%、1.0%和1.5%藿朴蒲苓散,试验期30 d,试验期间舍内温湿指数平均达79.11。试验末检测育肥羔羊生长性能、养分表观消化率、瘤胃发酵参数和血清生化指标。结果表明：1)饲喂0.5%藿朴蒲苓散的羊日增重显著高于对照组(P < 0.01);日饮水量和日采食量在不同组间未表现出显著性差异(P>0.05)。从生理指标分析,饲喂中草药的羊直肠温度和呼吸频率与对照组比较均未表现出显著性差异(P>0.05)。2)0.5%组的干物质(DM)、中性洗涤纤维、酸性洗涤纤维、粗蛋白、钙和磷等养分表观消化率均显著高于对照组(P < 0.05),DM消化率较对照组提高7.20%(P < 0.01),而1.0%和1.5%组的消化率较对照组未表现出显著性差异(P>0.05)。3) 从血清生化指标上,3个给药组的生长激素均显著高于对照组(P < 0.05),0.5%组含量最高,较对照组提高16.90%;且0.5%组的甲状腺素含量显著高于其他组(P < 0.05)。4)从瘤胃发酵参数分析,3个给药组总挥发性脂肪酸含量、乙酸和丁酸含量均显著高于对照组(P < 0.05),分别是对照组的1.19~1.30倍、1.18~1.24倍和1.28~1.43倍。综上,本试验条件下,日粮中添加藿朴蒲苓散有助于缓解育肥羔羊的热应激,添加量以0.5%效果更佳。     

Lysine restriction and realimentation affected growth,blood profiles and expression of genes related to protein and fat metabolism in weaned pigs

To investigate the effects of lysine restriction and subsequent realimentation on growth performance, blood profiles and gene expression of leptin and myostatin, 128 weaned pigs [initial body weight (BW) 6.96 ± 1.07 kg, 26 ± 2 days of age] were randomly allotted to four treatments. The starter diets during the first 2 weeks (P1) contained 100%, 80%, 70% or 60% of recommended lysine levels ( National Research Council, 1998 ). Then, common grower 1 and 2 diets were offered for 2 weeks (P2 and P3) each. During P1, average daily gain (ADG) was linearly reduced (p < 0.05) with the increasing levels of lysine restriction. Growth rate was greater in pigs previously fed lysine‐restricted diets than well‐fed pigs although it did not reach a significant level during realimentation. However, the final BW and overall ADG were the lowest (p < 0.05) and F/G was poor in pigs fed 60% lysine diet. Relative visceral organ weights and composition of skeletal muscle were similar (p > 0.05) among the treatment. Blood triglyceride and glucose levels were increased (p < 0.05) during P1, while blood urine nitrogen, total protein and albumin levels were decreased (p < 0.05) during P2 with the reduction in dietary lysine levels. The abundance of myostatin mRNA in skeletal muscle and leptin mRNA in subcutaneous adipose tissue were lower (p < 0.05) in lysine‐restricted pigs than in pigs fed non‐restricted diets. In conclusion, 80% and 70% lysine restriction of starter diets resulted in inferior growth and compensatory growth effect was noted during realimentation, while 60% lysine restriction had a negative influence on growth performance. Moreover, the changes in myostatin and leptin mRNA abundance caused by nutritional manipulations may be involved in the regulation of protein and fat deposition in young pigs.     

贵阳市奶牛小区奶牛繁殖性能调查

本文就贵阳市具有典型代表性的某奶牛小区奶牛的繁殖性能进行调查,调查结果表明：该奶牛养殖小区2007～2009年的平均年受胎率为83.0%,产犊间隔时间为427.00±3.36d,产后子宫复旧时间为39.94±1.72d;产后瘫痪、胎衣不下、子宫内膜炎及死胎的发病率均有逐年下降的趋势,但乳房炎和肢蹄病的发病率却呈上升的趋势。该奶牛养殖小区的胎衣不下、乳房炎、子宫内膜炎及肢蹄病的发病率仍较高,严重影响了该小区的经济效益。     

酵母培养物对产蛋鸡生产性能、蛋品质及鸡蛋卫生指标的影响

本试验旨在研究酵母培养物(YC)对产蛋鸡生产性能、蛋品质及鸡蛋卫生指标的影响。选取2 304只210日龄的罗曼褐产蛋鸡,随机分成4组,每组3个重复,每个重复192只产蛋鸡。对照组(YC0组)饲喂玉米-豆粕型基础饲粮,试验组(YC0.2组、YC0.4组和YC0.6组)分别饲喂在基础饲粮中添加0.2%、0.4%和0.6%酵母培养物的试验饲粮。试验期9周。结果表明:1)与对照组相比,YC0.4组和YC0.6组平均蛋重显著增加(P0.05),破蛋率显著降低(P0.05);YC0.2组、YC0.4组和YC0.6组软蛋率显著降低(P0.05)。2)与对照组相比,YC0.4组和YC0.6组蛋壳厚度显著增大(P0.05);YC0.2组、YC0.4组和YC0.6组蛋黄颜色的亮度值显著降低(P0.05),黄度值显著升高(P0.05);YC0.6组蛋黄颜色的红度值显著升高(P0.05)。3)与对照组相比,试验第3、9周,YC0.2组、YC0.4组和YC0.6组的蛋壳表面大肠菌群数量显著降低(P0.05);试验第3、6周,YC0.4组蛋壳表面细菌总数显著降低(P0.05)。4)对照组组相比,YC0.6组粗蛋白质、能量和干物质表观消化率显著提高(P0.05)。5)与对照组相比,YC0.2组、YC0.4组和YC0.6组盲肠乳酸杆菌数量显著降低(P0.05)。由此可见,饲粮添加0.4%和0.6%的酵母培养物能够改善产蛋鸡蛋品质,提高饲料消化率;饲粮添加0.2%、0.4%和0.6%酵母培养物均能够改善产蛋鸡的生产性能,减少大肠杆菌的数量,抑制盲肠中沙门氏菌的产生。综合考虑,产蛋鸡饲粮中酵母培养物适宜添加量为0.4%。