Porcine reproductive and respiratory syndrome is a serious disease,causing significantly economical impacts on the swine industry worldwide.Because of the mechanism of virus infection,the characteristics of antibody-dependent enhancement and a high degree of variability,the commercial vaccines currently exist defects that can't completely prevent the respiratory system and placental transmission of porcine reproductive and respiratory syndrome virus(PRRSV).Therefore,according to the pathogenic characteristics,PRRSV immune characteristics and biological characteristics,the new vaccines are designed which have important significances to the prevention of the disease.

近几年，像AA、艾维茵等大型肉鸡在市场中占有的比例逐渐减少，而以山林、果园、荒地等养殖的本地鸡数量逐渐增加。在山林中饲养本地鸡具有投入少，成本低，鸡只运动场地大，发病少，成活率高，商品鸡毛色好，有光泽，经济效益高等优点，深受消费者喜爱。

1 发病情况 黑龙江省肇东市某养鸡户养鸡2万只,饲养面积300 m2,采用双层网上平养,每30d出栏一批,每批育雏2 000只,空舍10～15 d,经消毒后进下一批雏,循环饲养.2011年8月份,饲养至3周龄的肉仔鸡突然发病,3d内发病600多只,死亡117只.主要见红白色下痢,按球虫病选用"地克珠利(杀球灵)"治疗,连用2d,效果甚微.

<正>狐狸全身是宝,狐狸皮色泽艳丽,坚韧耐磨,轻柔暖和,可制作高档服饰,如裘皮大衣等。狐狸肉营养丰富,是宾馆、饭店里的高档菜肴,狐狸的心脏、肺脏、胆肝有药用价值,狐狸粪还是优质的有机肥[1]。自我国加入WTO后,狐狸皮出口数量也在逐年增加,狐狸皮的市场价格有所上涨,狐狸养殖方兴未艾。目

[Objective] To investigate the optimum breeding density of phoenix chichken in loquat orchard.[Method] Phoenix chickens were bred with the density of 2 250,3 000,3 750,4 500,5250 and 6 000 chickens/hm2,and the survival rate production performance and profit were studied,respectively.[Result] The optimum density of phoenix chicken in loquat orchard was 4 500 chickens/hm2.[Conclusion] The research provides a basis for breeding chickens in loquat orchard of Chengdu City.

<正>狐狸全身是宝,狐皮可制作高档服饰如裘皮大衣等,狐肉营养丰富,狐心、肺、胆、肝有药用价值,狐狸粪还是优质的有机肥。狐狸养殖是特种养殖,效益高、风险大、技术要求高。1品种选择与购买养殖户在养殖前,要全面评估养殖条件,选择适宜的狐狸品种,根据是以狐皮还是以狐肉为主要产品来选择品种,

<正>果园养猪新技术不仅能生产无公害水果,而且能在果园养出生态猪,经济效益相当可观,是种植业和养殖业的完美结合。1果园要求

<正>美味、绿色、营养、保健越来越成为人们近些年来的热门追求。其中野猪肉正是满足目前市场上人们消费需求的食品之一。野猪肉鲜美细嫩,属低脂肪低胆固醇肉类,其肌肉中所含的动物蛋白和不饱和脂肪酸具有降低血脂、防止动脉硬化所致的冠心病和脑血管病的作用,正是人们真正追求的绿色、营养、滋补食品。纯种野猪具有生长速度慢、

<正>近几年,随着经济的发展,人民生活水平的不断提高,人们的生活观点、方式都发生了深刻变化,从单纯追求数量型转向数量质量兼顾型。作为提高人们生活水平和质量的商品花卉也随之发生重大转变,花卉新品种、新类型不断涌现。在这样背景下,水培花

试验选用10株芽孢杆菌,对其产淀粉酶的能力进行了测定,测定方法分初选(染色法)和复选(3,5-二硝基水杨酸显色法)两步。结果表明,其中9株菌具有产淀粉酶能力,以编号为Pab03、Pab02的两株枯草芽孢杆菌的产酶活性最高,在未优化发酵条件的前提下,酶活力分别达到31.331和21.521U,作为新型的消化酶饲料添加剂显示出广阔的应用前景。