提高饲料过瘤胃蛋白率的技术措施

过瘤胃蛋白指饲料中未被瘤胃微生物降解而直接进入小肠的蛋白质,是反刍动物吸收氨基酸的重要来源。通过降低饲料蛋白质在瘤胃内的降解率,提高蛋白质的过瘤胃率,增加氮在体内的沉积,可提高优质蛋白质饲料的利用率,从而提高反刍动物的生产性能。国内外对提高饲料过瘤胃蛋白进行了大量的研究,包括各种热处理方法、化学方法和物理包被等,文章综述了提高饲料过瘤胃蛋白的技术措施及其在生产中的应用效果。     

羊附红细胞体小鼠模型的建立

[目的]用人工感染的方法构建羊附红细胞体小鼠模型,并对其进行鉴定。[方法]将注射地塞米松的昆明小鼠以腹腔注射方式人工感染羊附红细胞体,通过镜检、巢式PCR检测、临床症状观察、剖检及病理形态学观察对感染情况进行鉴定。[结果]羊附红细胞体小鼠模型已成功建立。[结论]可以用昆明小鼠建立羊附红细胞体实验动物模型,不仅有助于该病的诊断,而且为羊附红细胞体流行病学、致病力、免疫学以及有效药物筛选等方面的研究提供了一种合适的动物模型。     

稀土元素钷(147Pm)在食草动物中的富集性

以１ ４ ７ Ｐｍ （ Ｎ Ｏ３ ）２ 溶液 （质量浓度３２×１０－ ３ μｇ／ｍ Ｌ, 放射性比活度为９６２ ｋ Ｂｑ／ｍ Ｌ） 喷施牧草, 并用其饲喂食草动物 （豚鼠）, 应用核素示踪技术研究豚鼠对１ ４７ Ｐｍ 的富集性。结果表明, （１） 喷施于牧草的１４ ７ Ｐｍ 被动物摄入后, 大部分通过粪便较快排出, 连续饲喂２５ ｄ 后, 其排出率为６１０５％ 和７５５４％ ; 连续饲喂１３ ｄ 后以普通饲料继续喂养３１ ｄ,１ ４ ７ Ｐｍ 排出率为６８９２％ 和７５８２％ 。（２） 滞留于鼠体的１ ４ ７ Ｐｍ 在脏器组织间呈不均匀分布, 其中, 肌肉内含量较低, 骨髓、骨骼、心脏和脂肪中较高, 具有明显的选择性蓄积; 睾丸和肾脏滞留量亦高, 但是终止摄入后排出较快。     

Pattern of herbage intake rate and bite dimensions of rotationally grazed dairy cows as sward height declines

To allow improved prediction of daily herbage intake of dairy cows in rotational grazing systems, intake behaviour was assessed throughout the day in 24‐h paddocks. Herbage intake in 16 lactating Holstein–Friesian cows was assessed using the short‐term (1‐h) weight gain method at four predetermined natural meal times throughout the day (early morning, T1; late morning, T2; mid‐afternoon, T3; and early evening, T4). The study comprised two 4‐day experiments, each with a cross‐over design of four blocks. In both experiments, cows grazed a 24‐h paddock daily, and the effect of the immediately previous grazing experience on intake behaviour was investigated throughout the day, taking account of daily fluctuations in the short‐term physiological condition of the cows. Experiment 1 was carried out to investigate overall grazing behaviour during meals as a sward is progressively depleted during the day, with intake being assessed within the paddock and, hence, on a depleted sward. Experiment 2 similarly investigated the effect of sward depletion and physiological condition throughout the day on intake, but cows were removed to fresh, undefoliated swards during intake measurement periods; thus, intake rate was not influenced by differences in sward condition. Intake behaviour from both experiments was compared to establish the effect on herbage intake of changes in sward state and non‐sward factors. In Experiment 1, sward surface height, available herbage mass, proportion of leaf and green leaf mass declined as the day progressed. Bite mass declined with sward depletion, and mean intake rate was 1·64 kg dry matter (DM) h^–1, which was significantly lower at T3 (P < 0·01) than during other meals. In Experiment 2, plot sward conditions did not change throughout the day, and intake behaviour also remained constant, with a mean intake rate of 2·11 kg DM h^–1. Mean bite depth as a proportion of pregrazing extended tiller height was constant throughout the day (mean 0·32). The results show that, although cows grazed throughout the day on progressively depleted swards, indicative of rotationally grazed paddocks (Experiment 1), bite mass declined linearly and intake behaviour was variable. However, where intake was assessed on high‐quality, undefoliated swards (Experiment 2), intake behaviour was similar regardless of the time of day and the immediately previous experience. There was some indication of an interaction between the effects of the sward and the physiological condition of the animal on herbage intake.     

不同耕作方式对松嫩平原半干旱区玉米土壤生物特性影响

为探究不同耕作方式对松嫩平原半干旱区玉米土壤环境的影响,设置旋耕垄作(CK)、旋耕垄作深松、免耕、免耕深松、旋耕平作和旋耕平作深松6种耕作方式,研究不同耕作方式对土壤细菌、土壤真菌、土壤放线菌、土壤动物和土壤动物群落组成的影响。结果表明,免耕和免耕深松处理能够显著提高土壤细菌、真菌和放线菌数量,提高幅度分别为18.57%～31.01%、27.99%～48.76和12.32%～21.95%。免耕和免耕深松处理显著提高了0～30 cm土壤微生物量碳和微生物量氮含量,提高幅度分别为8.33%～16.55%和9.70%～19.89%。平作深松处理土壤动物捕获量最高,免耕和免耕深松处理Shannon-wiener指数最高,表明免耕更有利于农田生态系统土壤生物的生存环境的维护。     

单轴卧式全混合日粮混合机的试验研究

介绍了一种单轴卧式全混合日粮混合机,阐述了其主要结构及工作原理.为了优化其运动参数,采用二次回归正交旋转组合试验设计,对3个试验因素进行了以混合均匀度为评价指标的试验研究,得出运动参数的合理组合,即转子转速宜取50～60 r/min,混合时间宜取9 min,充满系数大于0.5.     

纳豆芽孢杆菌作为益生菌饲用的研究现状

作者系统概括了纳豆芽孢杆菌作为饲用微生物的特点、作用机理和饲用效果。纳豆芽孢杆菌是从日本发酵大豆中分离出来的，它被运用于动物饲养并取得了良好效果。阐述了纳豆芽孢杆菌在肠道中的活性和增殖作用，其抗菌物质能抑制肠道好氧性致病菌生长，它富含多种酶类可提高饲料消化率，它还能刺激动物机体免疫反应从而提高机体免疫力。最后作者提出了纳豆芽孢杆菌作为饲用微生物所面临的问题并指出了发展方向和前景。     

心包积液-肝坏死综合征高免卵黄抗体的研制

采取心包积液-肝坏死综合征病鸡的肝脏匀浆冻融,接种SPF鸡胚,制备尿囊液灭活水苗,用两种免疫程序对产蛋鸡进行免疫,用琼脂扩散试验检测其卵黄抗体水平,制备高免卵黄抗体。经中和试验和临床试验,结果显示高免卵黄抗体对该病的预防和治疗效果明显。     

舍饲养殖小区建设的动物防疫条件

本文就甘肃省瓜洲县建设符合动物防疫条件舍饲养殖小区的必要性和舍饲养殖小区动物防疫合格的标准提出自己合理化的建议,希望能够促进瓜洲县牛羊养殖业得到又快又好的发展。     

农民利益预警调控初探

从明确农民利益预警调控的思路与特性出发,通过确定农民利益失衡区正、负指标体系以及农民利益预警线,进行农民利益失衡区的分类处理。对农民利益预警调控程序进行了探讨,并对如何具体探定农民利益调控预警线进行了有益的尝试,为保障农民利益,解决“三农”问题提供参考。