猪链球菌病的临床诊断与治疗

猪链球菌病是由多种致病性链球菌感染引起的一种急性、热性传染病.该病各季节均可发生,并且长期广泛存在于各种生猪养殖场中,在临床的四种类型中尤以脑膜炎型和关节炎型发生更加普遍.为此,笔者针对几年来的临床诊疗方案加以总结,以供同行参考.     

牛胚胎日龄与移植时间对妊娠率的影响

为探讨胚胎移植过程中受体与胚胎日龄的最佳结合点,对移植受体牛的发情天数与胚龄进行了研究.选取北京奶牛中心的3种不同胚龄的A级胚胎,分成2组进行移植,A组采用随机移植方案,B组采用同步移植方案.B组妊娠率为(61.11%)高于A组的妊娠率(25.81%),两组之间存在显著性差异(P＜0.05).结果表明,在胚胎移植中同步移植好于随机移植的效果.通过本试验的研究,以期在生产实践中对胚胎移植技术的应用和推广有所借鉴.     

牙鲆口服A3α-肽聚糖最佳投喂方案的选择

在前期工作基础上,本实验在普通海水鱼饲料中添加了3．84g／kg（m／m）的A3α-肽聚糖（A3α—PG）,采用不同的投喂方案作用于牙鲆。以生长、溶菌酶、补体旁路激活活力（ACH50）、吞噬为评价指标,在实验期间的第14、28和42天分别取样进行测定,以评价不同投喂方案下肽聚糖制剂对牙鲆非特异性免疫力的影响。结果显示,14d内未见生长的明显差异,而在28d和42d后,4d投喂肽聚糖饲料＋3d投喂空白饲料（简称“4＋3”组）和7d投喂肽聚糖饲料＋7d投喂空白饲料（简称“7＋7”组）促生长效果最为明显（P〈0．05）。溶菌酶活力在前14d内以“4＋3”组活力最强,至28d后各实验组活力基本一致,42d时,除“7＋7”组外,各组均比对照组有明显提高（P〈0．05）。ACH50活力以1d肽聚糖饲料＋1d空白饲料（简称“1＋1”组）活力最强,在整个实验过程中均比对照组表现出大幅提高（P〈0．05）。吞噬活力在不同时间不同投喂方式下所表现出的水平有一定的波动,但从整体来看,以“4＋3”组对其诱导能力最强,前14天内,“4＋3”组与对照组及其他组相比未见明显提高,但在28d后其活力值上升较快,且维持到42d仍有较高水平。综上所述,从不同投喂方案对生长及非特异性免疫力的调节能力,并结合经济性与实用性来考虑,建议采用“4＋3”的间隔投喂方案给予牙鲆A3α-肽聚糖,以提高其非特异性免疫力和抗病力。     

猪人工授精与自然交配的受胎效果比较

对328头1～3胎的大白母猪实施了人工授精(2次、3次)和自然交配(3次),比较了两种配种方法和输精方式对母猪受胎率和产仔数的影响。结果表明:两种配种方法和输精方式对3个胎次母猪的受胎率和窝均产仔数影响均不显著(P0.05)。说明人工授精可以取代自然交配在规模化猪场推广应用,并且在规模化猪场实施2次人工授精也是可行的。     

黑龙江垦区肉牛杂交组合的效果观察

引进国外优秀公牛与本地黄牛进行杂交组合,在黑龙江垦区有3种较常用的模式,作者为此进行了大量的试验研究,拟在通过杂交组合模式,分析几种杂交组合的效果。     

对虾免疫机能研究概况

Shrimp farming is an important source of revenue and employment in many developing countries.However, infectious diseases have adversely affected the profitability of shrimp industry. For this reason, disease prevention is a priority and shrimp immunology has become a crucial research area of this field. In this paper, the current importance and problems of shrimp-culture were described and the research advances in shrimp immunological defence mechanisms were summarized. The immunological tools are powerful and useful to evaluate the health state of the shrimp. The immunologies of shrimp mainly consist of cellular immunity and humoral immunity. In regard to cellular parameters, they are composed of haemocyte count (THC), differential haemocyte count (DHC) and reactive oxygen intermediates (ROIs). The immunity ceils exert their defence functions through phagocytizing, enveloping, etc, and the changes of THC and DHC are related to health state of shrimp. The ROIs generated during post phagocytic event which maybe an important marker to evaluate the immunological capability and phenoloxidase activity have been considered as a potential marker which is relevant to the health of the shrimp too. Concerning humoral parameters, prophenoloxidase (ProPO) and phenoloxidase,antimicrobial peptides and proteins, hemagglutinin and plasma proteins were described. The determining methods of immunity parameters were discussed. The response of shrimp to pathogens such as bacteria, virus, etc. and environmental factors such as DO, pH, etc, were also reviewed. It is well-known that the immune responses induced by immunizing crustacean or shrimp are mainly the non-specific immune responses. The potential of immunological parameters, including the changes of THC and DHC, the production of ROIs, phenoloxidase (PO) activity, antibacterial activity of plasma, and so on, to appraise the healthy state of shrimp were partly discussed. The future directions for the evaluation of the immunological capability of shrimp were proposed.     

海参疾病学研究进展

海参具有极高的营养和药用价值,历来被视为海珍奇品。近年来,海参价格不断上涨,市场需求量迅速增加,随着采捕强度的增大,导致自然资源量急剧减少。为解决市场膨胀和资源缩减问题,海     

A3α肽聚糖对凡纳滨对虾幼体酸性磷酸酶和碱性磷酸酶活力的影响

用含不同质量分数(0.005%、0.01%、0.1%)A3α肽聚糖(PG)的饵料投喂及在育苗水体中添加不同质量浓度(0.005、0.01和0.05 mg/ml)的PG浸浴凡纳滨对虾幼体,以投喂不添加PG的饵料作对照,另设投喂活饵的试验组作参考;饲养7 d后,检测PL1期仔虾体内酸性磷酸酶(ACP)和碱性磷酸酶(ALP)活性.结果显示:PG经浸浴和口服能促进幼虾ACP和ALP活性提高;经活饵投喂的幼虾的ACP和ALP活性也较高.活饵组的ACP和ALP活性,0.01%PG添加量组和0.005 mg/ml PG的浸浴组幼体的ACP活性,0.01%和0.1%PG添加量组、PG质量浓度为0.01、0.05 mg/ml的浸浴组的ALP活性均较对照组有显著提高(P < 0.05);口服组和浸浴组ACP活性均与PG浓度正相关,而口服组中0.01%PG添加量组ALP活性最高,浸浴组中PG浓度与ALP活性正相关.试验结果表明,PG能提高幼虾的非特异性免疫力.PG用于育苗的口服质量分数建议为0.05%～0.1%,浸浴质量浓度为0.05 mg/ml.