赛加羚羊在武威的饲养繁殖

通过对国家林业局甘肃濒危动物保护中心引进的赛加羚羊饲养繁育情况的观察分析,得知其从刚开始有效引进的12只发展到现在的171只,种群具有良好的繁育能力,并对武威半荒漠气候环境表现出较强的适应性。     

我国赛加羚羊种群壮大的主要影响因素

赛加羚羊自引入国内后,经过多年精心繁育,虽种群已表现出了良好的适应性和较高的繁殖率,但种群大小还未突破瓶颈。本文通过多年的研究,探索研究影响种群扩繁的主要因素除了赛加羚羊寿命短之外,场地承载容量、春季青黄草转换、交配期体能巨耗、疫病以及种源引入困难也是影响种群壮大的主要原因。     

赛加羚羊初生体重与体尺的相关性研究

为了提高测定效率,运用SPSS软件对30只赛加羚羊初生羔的体尺、体重结果进行了相关分析和通径分析,并建立了最优回归方程。结果表明:赛加羚羊初生体重(Y)与体直长(X_1)、体高(X_2)、胸深(X_3)、胸宽(X_4)、胸围(X_5)、尾长(X_6)、耳长(X_7)及管围(X_8)均呈极显著正相关(P0.01),其中体直长(X_1)和胸围(X_5)是体重(Y)的最主要决定变量。初生羔羊体直长(X_1)和胸围(X_5)对体重(Y)的最优回归方程为Y=-1.219+0.052X1+0.072X5。     

气候因子对母猪繁殖性能的影响

对长白母猪两年533胎次4个繁殖性能指标与主要气候因子（月平均气温和相对湿度）的相关和曲线回归分析表明，母猪受胎率与月平均气温，相对湿度存在着显著的负相关关系（－0．505，－0．49，P＜0．05），且母猪的受胎率与月平均气温之间的相关性与相对湿度有关，月平均气温与窝产仔数，21日龄窝重呈负相关（－0．387，0-0.363)，而与仔猪的成活率呈正相关（0．352），但它们之间的相关关系均不显著（P＞0．05），母猪的受胎率与月平均气温之间存在着显著的曲线回归关系（P＜0．05），而与相对湿度的曲线回归方程无意义，母猪的窝产仔数，仔猪的成活率和21日龄窝重与月平均气温和相对湿度之间的曲线回归关系不显著（P＞0．05），在气温为2．4－36．6℃，相对湿度为61％－89％，的范围内，母猪的受胎率与月平均气8温之间的回归方程为：Y＝118．635e-^-0.0173x。     

气候因子对母猪繁殖性能的影响

对长白母猪两年533胎次4个繁殖性能指标与主要气候因子(月平均气温和相对湿度)的相关和曲线回归分析表明,母猪受胎率与月平均气温、相对湿度存在着显著的负相关关系(-0.505, -0.49, P<0.05),且母猪的受胎率与月平均气温之间的相关性与相对湿度有关;月平均气温与窝产仔数、21日龄窝重呈负相关(-0.387,-0.363),而与仔猪的成活率呈正相关(0.352),但它们之间的相关关系均不显著(P>0.05);母猪的受胎率与月平均气温之间存在着显著的曲线回归关系(P<0.05),而与相对湿度的曲线回归方程无意义;母猪的窝产仔数、仔猪的成活率和21日龄窝重与月平均气温和相对湿度之间的曲线回归关系不显著(P>0.05). 在气温为2.4～36.6℃, 相对湿度为61%～89%的范围内,母猪的受胎率与月平均气温之间的回归方程为Y=118.635e-0.0173x     

气候因子对母猪繁殖性能的影响

通过249窝(胎)次母猪于2003￣2005年各月份产仔数、活仔数、断奶头重的统计分析,研究不同月份的气温、相对湿度等主要气候因子对母猪繁殖性能的影响。分析结果表明7月份平均气温最高,母猪繁殖力最低。从而提示在母猪生产中应该注意在高温季节加强饲养管理、改善环境条件,并合理     

赛加羚羊被毛及毛纤维特征对其环境适应性的研究

通过对赛加羚羊（Ｓａｉｇａｔａｔａｒｉｃａ）的被毛特征、毛纤维类型、结构、长度、密度、细度及强伸度的观察测定,结果为：赛加羚羊毛纤维均为有髓毛,其髓质发达,鳞片小呈蛇鳞状,被毛主要部位毛长仅２．９１ｃｍ,密度为１９２０根／ｃｍ２,毛纤维直径可达１０３．７μｍ而单纤维强伸度在１５ｇ重锤下为０。并指出：以上种种特性使赛加羚羊具有较强的回避天敌和抵御寒冷气候的能力,均与栖息地环境相适应。     

赛加羚羊在半放野状态下的繁殖规律研究

为探明赛加羚羊在半荒漠地区半放野状态下的繁殖规律,通过资料分析与现场观察,研究了近30年来饲养于国家林业局甘肃濒危动物保护中心的赛加羚羊繁殖情况。结果表明:赛加羚羊的产仔率126.67%,产羔成活率87.72%,死亡淘汰率18.03%,存活率81.97%;发情周期21.46 d±2.59 d;雌羚羊7月龄性成熟,情期受胎率86.61%,妊娠期140.73 d±2.25 d,每胎产1~2仔,双胎率56.14%;羔羊初生体重2 882.32 g±45.93 g、体长45.56 cm±0.54 cm,雌、雄羔间初生体重与体尺均无显著性差异(P0.05),羔羊初生体重与体长存在相关性(r=0.313,P0.01)。在此基础上,分析对比了半放野状态下与人工圈养状态下赛加羚羊的繁殖情况,发现半放野状态下其产仔率、产羔成活率、存活率、双胎率和羔羊平均体重等主要繁殖性能指标均比圈养状态下高;此外,赛加羚羊自引入后对所在半荒漠地区气候环境进行了一个适应过程,发情期逐渐提前,由刚引进初期的12月中旬逐渐提前到11月中下旬,分娩盛期也相应提前,由刚引进初期的5月中上旬逐渐提前到4月中下旬,到5月初已基本结束产羔。说明赛加羚羊在繁殖上有明显的季节性和时间性,与同亚科动物相比,具有性成熟早而寿命短(4~5岁)、受胎率和繁殖成活率高、交配季节后淘汰率高等特点。     

半番鸭繁殖性能研究──（二）雌性半番鸭繁殖性能研究（摘要）

从北京鸭（♂）×番鸭（♀）属间杂种Ｆ１代大群群体中选出生殖器官有不同程度发育的雌性半番鸭，发现其有不同程度的繁殖力，但与亲本差异大。雌性半番鸭开产晚、蛋少、开产蛋重与３００日龄蛋重一致，蛋小、蛋黄相对小，哈夫单位高、蛋白相对重比亲本高。获得一枚北京鸭（♂）×半番鸭（♀）的受精蛋。其胚胎在发育过程中死亡。笔者认为雌性半番鸭卵巢发育不全是造成半番鸭繁殖力低的直接原因。     

印度黑羚羊的饲养与繁殖

本文报道了印度黑羚羊在广州动物园的饲养管理、繁殖研究情况。饲养、繁殖成功的关键是 :设置合适的生活环境 ,调配合理的饲料及精心的饲养管理     

Toxoplasmosis in nilgais (Boselaphus tragocamelus) and a saiga antelope (Saiga tatarica).

Three captive female nilgais (Boselaphus tragocamelus) either showed late-term abortion or their newborn calves died within 2 days of birth. Toxoplasma gondii DNA was demonstrated in the brain and liver of each fetus and in one of the two neonates by single-stage polymerase chain reaction (PCR) with TGR1E and by seminested PCR with B1 gene. Retrospectively, antibodies titers > or =640 to T. gondii by indirect fluorescence were found in the sera of all three female and one male nilgais. No other cause of abortion was detected. Fatal toxoplasmosis was also diagnosed in one captive, adult female saiga antelope (Saiga tatarica), which died suddenly. Toxoplasma gondii was detected in the liver, lung, spleen, kidney, and intestine. An unusual finding was the presence of numerous tissue cysts in the liver of this animal. Toxoplasmosis was confirmed by PCR with TGR1E and immunohistochemically. Toxoplasmic hepatitis and pneumonia were considered to be the primary causes of death.     

Meat characteristics of Qinghai yak and semi-wild yak

Six domestic yaks aged 6 years, comprising three culling male and three culling female yaks, from the Qinghai Lake area and three male semi‐wild yaks aged 6 months from Datong Yak Farm were used to detect the levels of amino acids, mineral elements, residual heavy metals and pesticides in yak meat. The results showed that there was little difference in amino acid levels for different types of yak by age and sex. The meat of the adult male yak was 7.35 mg/kg higher in calcium (P < 0.05) and 124 mg/kg higher in phosphorus (P < 0.01) than that of the adult female yak. There was an obvious difference in zinc content, and there was also a significant difference for copper and sulfur between adult male and female yaks (P < 0.01). Iron was 8.85 mg/kg higher in semi‐wild yaks than in domestic yaks, but there were no differences for other minerals. The levels of residual heavy metals and residual pesticides were well within those allowed by the National Standard of China. Furthermore, the data showed that introducing wild yak’s blood did not result in a quality change in the domestic yak meat. Yak meat from Qinghai Plateau has the characteristics of being non‐polluted and rich in amino acids in comparison with local yellow cattle meat.     

母猪配种前后气候因子与窝产仔数的关系

本文分析了某猪场１９９３年３月至１９９４年３月之间１７２２胎窝产仔数，夏季（１９９３年６月至９月份）配种所产仔猪数显著低于其它月份（Ｐ〈０．０５）。母猪配种时期气候因素如平均日照，温度，相对湿度和风速与窝产仔猪数的相关系分别为－０．５１６，－０．７７５，－０．２８１，－０．７５１，用通径分析法对以上相关系及各气候因子间的相关系进行部分，求出以上各气候因子以窝产仔猪数的通径系数分别为０．５０７，－０     

环青海湖北岸草甸化草原植物群落与气候因子的关系

通过对青海湖北岸草甸化草原植物群落生长发育变化规律与气候因子进行相关分析,揭示了影响该地区草地植物群落特征的关键气候因子,为当地合理利用草地和提高单位面积产草量以及应对气候变化提供科学依据。结果表明,随着全球气候的逐年变暖,青海湖北岸地区的气温和降水量也有逐年升高的趋势,同时,伴随着蒸发量的增大和日照时数的减少,牧草的一些生物学特征也随之发生了改变,表现在牧草返青期、抽穗期、开花期和种子成熟期逐年提前,而牧草黄枯期却逐年延迟,牧草高度和地上生物量也呈现出逐年升高的趋势;对牧草来说,年均蒸发量主要影响牧草的高度,而年降水量则更大程度上影响着牧草的产量,生长期长短则主要与日照时数有关。     

Associations between housing and management factors and reproductive performance in 327 Norwegian sheep flocks

Background

Housing sheep in insulated, warm buildings, which is common in Norway, involves high buildings costs, but has not been reported to improve health and performance. Few studies have dealt with the association between housing and management and reproductive performance.Data on housing and management during the indoor period from a questionnaire were merged with herd level data from the Norwegian Sheep Recording System, and the material included 327 sheep flocks. Associations between housing and management factors and reproductive performance were analyzed by means of multivariate regression models and grouped logistic regression.

Results

There was no difference in reproductive performance between warm and cold housing. Number of live born lambs born per pregnant ewe was highest in flocks with 10 or less ewes per pen, and lowest in flocks with more than 40 ewes per pen. Rate of barren ewes was lowest, and number of lambs per ewe at the end of the indoor period was highest in flocks where the sheep were regrouped according to number of foetuses (lambs) identified by scanning. A higher total number of lambs born per pregnant ewe and lambs per ewe at the end of the indoor period were found where other available housing facilities or outdoor areas were used in addition to the main housing unit in the lambing season. The rate of stillbirths was lowest on farms where sheep was the only animal production. None of the factors evaluated had any significant association with mortality of live born lambs in the indoor period. Lowest number of lambs per ewe at the end of the indoor period was found on farms where other family members/hired labour were caretakers as compared with the farmer or spouse/cohabitant, and highest numbers were found where caretakers were older than 60 years of age. Reproductive performance was lower in the Spæl Breed than the Norwegian White Sheep.

Conclusion

Housing systems per se are of minor importance, whereas management practices in the indoor period should be expected to improve reproductive performance.