试验选择健康、体重相近的21日龄雌性临武鸭300羽,分别设3、4、5、6、7只/m2 5个处理,每处理6个重复(网床面积为2 m2),试验期42 d.结果表明:不同饲养密度组间试鸭平均采食量和存活率均无明显差异(P＞0.05);7只/m2组试验鸭末重和日均增重均显著低于3、4、5只/m2组(P＜0.05);而料重比以7只/m2组最高,显著高于3只/m2组(P＜0.05);3、4、5和6只/m2 4个饲养密度组间试验鸭末重、日均增重和料重比差异均不显著(P＞0.05).总体上试验鸭末重、日均增重和料重比项指标均表现出以下规律:3只/m2组最好,其次为5、4和6只/m2,7只/m2组最差.回归分析表明,平均日增重随饲养密度的增加呈二次曲线关系:y日增重=-0.1464x2+-1.0313x+-19.777(P=0.003,R2 =0.9277),求导得出饲养密度为3.53只/m2时,试鸭获得最大平均日增重21.59 g/d.结合生产实际,21～63日龄临武鸭网上平养密度以3.5～5只/m2为宜.

It is widespread on the drug resistance of bacteria,R plasmid is a major genetic factor mediating drug-resist-ant of E.coli.It is reviewed by the Drug Resistance and Elimination of R Plasmids from Escherichia coli.The aim of the paper is to provide reference for bacteria to restore their sensitivity to antibiotics.

续第7期第40页 由于雏鸡的体温调节机能不完善、代谢旺盛、消化力弱、免疫机能差、对外界温度适应能力弱,因此要对雏鸡进行特殊的饲养管理. 1.鸡舍的清理和消毒 育锥前详细检查雏鸡舍内的设施设备是否完好,保温与通风设备是否正常,并对鸡舍进行彻底清扫和消毒.可采用福尔马林和高锰酸钾熏蒸消毒的方法,按1立方米空间用10毫升福尔马林和5克高锰酸钾的量进行熏蒸,可以用过氧乙酸、百毒杀等药物对墙壁、屋顶及地面进行喷洒消毒.

This experiment was conducted to study the effects of dietary methionine ( Met ) level on growth performance, egg quality and serum biochemical indices of Linwu ducks aged form 30 to 38 weeks, and to e?valuate Met requirement of Linwu ducks during the peak laying period. A total of 200 healthy Linwu ducks with nearly same body weight were randomly assigned to 5 groups with 5 replicates in each group and 8 ducks in each replicate. Ducks in the 5 groups were fed basal diets supplemented with 0.27%, 0.32%, 0.37%, 0.42%and 0.47% Met, respectively. The experiment lasted for 63 days. The results showed as follows: 1) dietary Met level had no significant effects on laying rate and qualified rate of egg ( P>0.05) . The average daily feed intake and feed/egg in 0.37%, 0.42% and 0.47% Met group were significantly lower than that in 0.27% Met group ( P<0.05) , but the daily egg yield and average egg weight in 0.37% Met group was significantly higher than that in 0.27% Met group (P<0.05).The 0.37% Met group obtained the best performance except qualified rate of egg. 2) Dietary Met level had no significant effects on egg?shaped index, egg shell thickness, egg yolk color, yolk ratio, percentage of eggshell and protein ratio (P>0.05), but albumen height and Haugh unit in 0.42% Met group were highest and significantly higher than those in 0.27% and 0.32% Met group ( P<0.05) . 3) Dietary Met level had no significant effects on the contents of total protein, albumin, urea nitrogen, uric acid and malondialdehyde in serum (P>0.05). Compared with 0.27% Met group, the serum superoxide dis?mutase content in the other four groups were significantly improved ( P<0.05) . The serum glutathione ( GSH) and glutathione peroxides content in 0.37%, 0.42% and 0.47% Met groups were significantly higher than that in 0.27% Met group ( P<0.05) . 4) There was a quadratic behavior for feed/egg and the content of GSH in se?rum according to the Met levels in the diets, with the requirements for those parameters established at 0.41%and 0.43%, respectively. In conclusion, dietary 0.41% to 0.43% Met level of Linwu ducks during the peak laying period can obtain the best performance, egg quality and serum biochemical indices. The Met recommen?ded of Linwu ducks aged form 30 to 38 weeks is 0. 41% to 0. 43%.

The aim of this study was to determine the effects of guar germ supplemented with compound en?zymes on nutrient, amino acid and energy utilization rates of Linwu ducks. Twenty?four healthy adult male Lin?wu ducks with body weight of about 2.0 kg were randomly divided into 3 groups with 8 replicates in each group and 1 duck in each replicate. Metabolic tests were carried out by hunger strike?gavage method. Ducks in group 1 and 2 were fed 60 g/d diet by gavage, diet of the group 2 was added with 250 mg/kg compound enzymes, and ducks in group 3 were fed 60 g/d diet with no nitrogen by gavage. The apparent utilization rate, true utili?zation rate, apparent metabolic energy ( AME) and true metabolic energy ( TME) of dry matter ( DM) , crude protein ( CP) , ether extract ( EE) , crude fiber ( CF) and 17 kinds of amino acids of guar germ supplemented with compound enzymes for Linwu ducks were determined. The results showed that the true utilization rates of DM, CP, EE and CF of guar germ were 67.07%, 67.57%, 65.52%, 82.88% and 77.39%, respectively. The AME and TME were 11. 34 and 13. 31 MJ/kg, respectively. The true utilization rates of 17 kinds of amino acids were 67.72% to 93.70%. Adding with compound enzymes, the true utilization rates of DM, CP, EE, CF and energy increased by 5.23%, 8.02%, 5.80%, 3.66% and 3.31%, respectively ( P>0.05) . AME and TME increased by 3.97% and 3.27%, respectively ( P>0.05) . The true utilization rates of 17 kinds of amino acids increased by 1.73% to 11.62%, and the true utilization rates of serine, glycine, leucine, tyrosine and phenylalanine were significantly increased (P<0.05). The results indicate that guar germ supplemented with compound enzymes containing protease and non?starch polysaccharide enzyme can improve utilization rates of nutrient, acid contents and energy of Linwu ducks.

采集衡阳某猪场119份血清样品进行伪狂犬病gE-ELISA （酶联免疫吸附试验）与gB-ELISA抗体检测。gE抗体检测结果表明，该猪场所检测猪群除公猪外都有伪狂犬病野毒阳性，是伪狂犬病阳性场，总阳性率为47%。公猪伪狂犬病野毒抗体阳性率为0，说明公猪暂时还没有感染伪狂犬病野毒，属于阴性猪；母猪群伪狂犬病野毒（gE）阳性率达50%~60%；30～40日龄及60日龄阶段猪群gE抗体阳性率分别为30%和55%，加上可疑的数量达到40%～65%，这阶段野毒抗体阳性估计主要受母源gE抗体的影响，且与母猪阳性背景基本一致，但也不能排除个别仔猪阳性抗体来自病毒感染；90～120日龄阶段gE阳性率不降反升，达到100%，说明90～120日龄阶段猪群是在保育转至肥育舍后被伪狂犬病野毒再次感染，gE抗体S/N值显著下降，抗体水平较高。gB抗体结果表明，该猪场伪狂犬病gB抗体阳性率为98%，公猪伪狂犬病gB抗体阳性率为100%，且公猪的gE抗体阴性，说明公猪gB抗体来源于疫苗免疫；母猪群伪狂犬病gB抗体水平高且整齐，可能是野毒感染和疫苗免疫综合作用的结果；30～40日龄阶段gB抗体水平整齐，这是由于母猪群gB抗体水平高且均匀整齐，其仔猪母源抗体相应较好；60日龄阶段gB抗体水平不整齐，这与母源抗体消退有关；90～120日龄阶段gB抗体水平显著提升，这可能是后期野毒感染所致，因为其gE抗体不降反升。综合该猪场gE和gB抗体检测结果分析表明，该猪场伪狂犬病在种猪群得到了有效控制，生产比较稳定，但种猪带毒且散毒，肥育猪的感染压力加大，造成病毒不断循环，肥育猪伪狂犬病野毒感染的控制成了稳定伪狂犬病阳性场的关键。目前，猪伪狂犬病阳性场应定时监测gE和gB抗体，根据猪场血清学检测结果，结合临床实际情况实时调整免疫程序，以便稳定生产和预防伪狂犬病的暴发。

To study the nutrient utilization of Linwu ducks affected by bone meal and feather meal supplemented with complex enzyme,a total of 40 healthy adult male Linwu ducks with the body weight of about 2.0kg were randomly and evenly divided into 5groups.Metabolic tests were carried out by'hunger strike- gavage method'to determine apparent and true DM,CP,EE,AA and energy utilization of bone meal and feather meal before and after adding complex enzyme.The results showed that bone meal supplemented with complex enzyme improved the true utilization rates of DM,CP,EE,Ash,Ca and TP by9.50%,7.72%,3.46%,8.52%,1.49% and 18.94%,respectively;AME and TME of bone meal were increased by 3.64% and 5.85%;amino acids true utilization were increased by 2.65%~24.52%.Feather meal adding with complex enzyme improved the true utilization rates of DM、CP and EE by 4.12%、3.21%and 1.64%;AME and TME of feather meal were increased by 2.38%and 2.14%;amino acids true utilization were increased by 0.75%~12.63%.The test results indicate that bone meal and feather meal adding with complex enzyme could improve Linwu ducks nutrient and AA utilization and metabolic energy.

本文报道了一养殖户肥猪发生急性死亡的病例,通过临床表现、剖检变化和试验室检测,确定为主要因感染巴氏杆菌,混合链球菌感染而导致的死亡.药敏结果显示,这两种细菌对恩诺沙星、阿莫西林和头孢噻呋高度敏感,对氟苯尼考、卡那霉素等猪场常用药不敏感.通过加强饲养管理和敏感药物保健、治疗等措施最终得到控制.

目的 探讨酵母硒对小鼠免疫功能的影响.方法 设实验组和对照组,在日粮中添加0.015％的酵母硒饲喂小鼠35天后,进行胸腺、脾脏和肝脏指数、抗体生成细胞、血清溶血素、碳廓清、GPX(谷胱甘肽过氧化酶)、LPF(小鼠淋巴细胞因子)等8项免疫指标的测定.结果 实验组的抗体生成细胞数、血清溶血素水平、腹腔巨噬细胞吞噬鸡红细胞能力和碳廓清能力及血清中GPX水平高于对照组;LPF水平有所降低,对免疫器官胸腺指数、脾脏指数和肝脏指数没有明显影响.结论 酵母硒可能有增强小鼠免疫功能的作用.

应用酶联免疫吸附试验(ELISA)检测了某规模猪场111份血清4种猪病血清抗体。检测结果显示:猪瘟、猪蓝耳病、猪伪狂犬病、猪口蹄疫的抗体阳性率分别为阳性率分别为69.4%、73.9%、82.0%、80.2%。结果表明:该规模猪场猪群四种猪病免疫抗体阳性率基本达到农业部规定的有效效价合格率水平≥70%,种猪群的四种猪病免疫抗体阳性率均维持在75%以上,免疫抗体水平整齐度较好。