长爪沙鼠生长与繁殖性能的主要指标测定

目的:探讨在普通级环境下饲养的长爪沙鼠的饲养管理、生长发育及繁殖等情况。方法:观测长爪沙鼠的饲养管理方法,记录0-12周的生长发育情况,统计1～5胎的初生个体重、窝产仔数、窝重和离乳重,测定成年长爪沙鼠主要脏器的重量、脏器重量/体重的比值。结果表明:在普通级环境下饲养的长爪沙鼠初生体重为2.8～3.2g,窝产仔4～9只,3～8周龄体重增长快,5周龄开始雌雄体重有显著性差异(P<0.05)繁殖性能好。     

猪应激综合征发生与控制的初步研究

猪应激综合征是在受到外界不良环境或有害因子的作用下出现的非特异性反应,主要有猪恶性高温综合征、猪急性背肌坏死、猪宰后腿肌坏死、猪自然应激综合征、水猪肉、突毙综合征等几种表现形式。通过对猪应激综合征的症状、发病原因、发病机制、病变特征以及控制措施等方面进行综述,并结合临床所见,以亟为生产实践提供参考。     

柠檬酸对小鼠睾丸组织抗氧化酶活性的影响

为研究柠檬酸对小鼠睾丸组织抗氧化酶活性的影响,将40只健康昆明系小鼠随机分为对照组(生理盐水)、柠檬酸低(180mg/kg)、中(270mg/kg)、高(360mg/kg)剂量组,各组小鼠每周腹腔注射相应剂量试剂0.2mL,连续注射3周,第3次注射后的第7天时颈椎脱臼处死小鼠,取其睾丸组织制作匀浆液检测过氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、乳酸脱氢酶(LDH)、总一氧化氮合酶(T-NOS)活性及丙二醛(MDA)含量。结果表明,与对照组相比,中、高柠檬酸剂量组小鼠睾丸组织SOD活性显著降低(P<0.05);柠檬酸处理组GSH-Px活性、MDA含量均显著下降(P<0.05);随着柠檬酸剂量的增加,LDH、NOS活性分别呈下降、上升趋势。此结果提示,一定剂量的柠檬酸可以降低小鼠睾丸组织SOD、GSH-Px活性,但可能通过NO途径减少睾丸细胞膜脂质过氧化,提高细胞膜的稳定性。     

多年生黑麦草高频再生体系的建立及农杆菌介导PEPC基因的转化

以多年生黑麦草(Lolium perenne L.)成熟种子作为外植体,建立其高频再生体系,通过农杆菌介导法将磷酸烯醇式丙酮酸羧化酶(PEPC)基因转入,为多年生黑麦草的抗逆转基因工作奠定基础。结果表明:种子充分灭菌后在附加6.0 mg·L^-1 2,4-D的培养基中诱导愈伤组织,诱导率可达61.33%。愈伤组织在2,4-D浓度减半的培养基上继代培养长势良好,分化培养基为MS培养基附加1.0 mg·L^-16-BA,分化率最高达到61.33%,在1/2 MS+0.5 mg·L^-1 NAA培养基中进行生根培养,生根率达100%。以该再生体系为基础,将获得的愈伤组织作为外植体进行遗传转化,经筛选培养后得到再生植株,通过PCR及实时荧光定量(Real-Time)PCR验证表明PEPC基因已成功转入,转化率为8.67%。试验结果将为多年生黑麦草抗性品种的研究奠定基础。     

正安县山羊主要疫病血清抗体检测报告

为了解正安县山羊主要疫病的发展趋势,通过虎红平板凝集试验、正向间接血凝试验、酶联免疫吸附试验等方法对正安县引进山羊进行布鲁氏杆菌病、O型口蹄疫、AsiaI型口蹄疫、山羊传染性胸膜肺炎、山羊痘等主要疫病血清抗体的检测。结果表明,O型口蹄疫、AsiaI型口蹄疫和山羊痘免疫抗体阳性率分别为79．42％、81．18％和99．58％,未免疫的布鲁氏杆菌病、羊传染性胸膜肺炎的丝状支原体山羊亚种和绵羊肺炎支原体未免疫抗体阳性率分别为0％、0％和3．81％。监测结果为山羊健康的引进、培育和扩繁提供了一些基础数据,对指导养羊生产有一定的意义。     

Effects of continuous low dose infusion of lipopolysaccharide on inflammatory responses,milk production and milk quality in dairy cows

The objective of this study was to evaluate the effects of continuous low dose infusion of lipopolysaccharide (LPS) on inflammatory responses and milk production and quality in lactating dairy cows. Eight Holstein cows were assigned to two treatments in a cross‐over experimental design. Cows were infused intravenously either with saline solution or with saline solution containing LPS from Escherichia coli O111:B4 at a dose of 0.01 μg LPS/kg body weight for approximately 6 hr each day during a seven‐day trial. The clinical symptoms and milk production performance were observed. Milk samples were analysed for conventional components, fatty acids and amino acids. And jugular vein and mammary vein plasma samples were analysed for concentrations of cytokines and acute phase proteins. LPS infusion decreased feed intake and milk yield. An increase in body temperature was observed after LPS infusion. LPS infusion also increased plasma concentrations of interleukin‐1β, serum amyloid A, LPS‐binding protein, C‐reactive protein and haptoglobin. LPS infusion decreased the contents of some fatty acids, such as C17:1, C18:0, C18:1n9 (trans) and C18:2n6 (trans), and most amino acids except for methionine, threonine, histidine, cysteine, tyrosine and proline in the milk. The results indicated that a continued low dose infusion of LPS can induce an inflammatory response, decrease milk production and reduce milk quality.     

Dietary Supplementation with Microencapsulated Lutein Improves Yolk Color and Lutein Content in Fresh and Cooked Eggs of Laying Hens

This study was conducted to compare the efficacy of diet supplemented with non-microencapsulated lutein (NL) and microencapsulated lutein (ML) in laying hens. A total of 270 Hy-line Brown laying hens (54 weeks old) were allocated to three groups with six replicates of 15 hens and were adapted to a wheat-soybean meal basal diet for two weeks. Next, the control birds were fed the basal diet, and the test birds were fed the basal diet supplemented with 600 mg/kg NL (12 mg/kg available lutein) or 90.1 mg/kg ML (10 mg/kg available lutein) for 35 days. Supplementation of lutein did not affect the productive performance of laying hens, but improved (P<0.05) the yolk color and red/green value (a*), with eggs from the ML group displaying improved color and a* values from the 15^th day of the experimental period. The blue/yellow value (b*) for the yolk showed an increase (P<0.05) through both NL and ML supplements. The yolk color of fried and boiled eggs and a* value of the yolk in fried eggs were improved (P<0.05) only through ML supplemented diet. Both NL and ML supplements resulted in lower (P<0.05) lightness and higher (P<0.05) a* values of yolk in boiled eggs, as well as higher (P<0.05) b* values in fried and boiled eggs. Yolk lutein content in fresh, fried, and boiled eggs was increased (P<0.05) in NL and ML groups with the latter being higher. In conclusion, ML improved yolk pigmentation and lutein retention in laying hens better than NL.     

乳牛蹄病与矿物元素

对山西五大牧场的水、土壤以及健康乳牛和蹄病乳牛血液抽样测定了其钠、钾、钙、镁、磷、铁、锌、铜、锰等元素的含量。探讨了矿物元素与乳牛蹄病的关系。结果表明，低锌、低硫、高锰、高镁、高铁可能是乳牛蹄病发生的易感因素     

乳酸芽孢杆菌制剂对AA肉鸡生产性能的影响

本试验研究在日粮中分别添加200mg/kg乳酸芽孢菌制剂和50mg/kg土霉素,对1～49日龄AA肉鸡生产性能的影响。结果表明,乳酸芽孢菌制剂组和土霉素组的全期平均日增重比对照组提高15.29%和9.10%(P<0.05),乳酸芽孢菌制剂组比土霉素组提高5.67%(P>0.05);乳酸芽孢菌制剂组和土霉素组的全期料肉比分别比对照组降低9.09%和7.36%(P<0.05),乳酸芽孢菌制剂组比土霉素组低1.87%(P>0.05);各组成活率差异不显著。     

2007年8月全国饲料生产情况分析

1生产总况8月份饲料生产保持了近几个月持续快速增长的良好势头,环比增幅超过10%,同比增长幅