芽孢杆菌制剂对蛋鸡产蛋性能、血清相关指标及肠道菌群的影响

将480只30周龄海赛克斯褐壳蛋鸡随机分成4组,每组4个重复,每个重复30只鸡。对照组（Ⅰ组）饲喂基础日粮,试验组（Ⅱ～Ⅳ）分别在基础日粮中添加100、200、300mg／kg水平的芽孢杆菌制剂。结果显示,Ⅱ组产蛋率显著高于Ⅰ组和Ⅳ组（P〈O．05）,料蛋比有所降低但不显著（P〉0．05）。Ⅱ组白蛋白和血糖含量显著高于Ⅰ组和Ⅳ组（P〈0．05）,芽孢杆菌对总蛋白、尿酸、总胆固醇和甘油三酯无显著性影响（P〉0．05）。各试验组ⅠgA和IgG含量均比对照组有所提高,但差异不显著（P〉0．05）。Ⅱ组和Ⅲ组C3浓度显著高于Ⅰ组（P〈0．05）,Ⅱ组C4浓度显著高于Ⅰ组和Ⅳ组（P〈0．05）。Ⅱ组和Ⅲ组回肠大肠杆菌的数量较Ⅰ组显著降低（P〈0．05）,乳酸杆菌显著提高（P〈O．05）。结果表明,芽孢杆菌制剂能够改善蛋鸡的生产性能,提高机体免疫力,促进肠道健康;蛋鸡日粮中添加100mg／kg芽孢杆菌制剂效果最佳。     

蛋氨酸锌对40日龄吉戎兔血清生化指标的影响

随机选取40日龄健康吉绒Ⅱ系吉戎兔72只,分成4组,每组3个重复,每个重复6只。试验I为对照组,饲喂基础饲料;试验Ⅱ、Ⅲ、Ⅳ分别添加40,80,120mg/kg蛋氨酸锌。结果表明,日增重在试验期0～15d期间及16～30d期间,试验Ⅲ与其它组差异显著（P〈0．05）,分别比对照组、试验Ⅱ、Ⅳ组提高13．94％和11．31％、6．60％和5．93％及7．47％和8．44％。料重比在试验期0～15d期间,试验Ⅲ与其它组差异显著（P〈0．05）,分别比对照组、试验Ⅱ、Ⅳ组改善12．23％、6．19％及6．95％;在试验期16～30d期间,试验Ⅲ和试验Ⅱ差异不显著（P〉0．05）,但与对照组和试验Ⅳ差异显著（P〈0．05）,试验Ⅲ比对照组、试验Ⅱ、Ⅳ组改善10．16％、5．60％、7．78％。试验Ⅳ血清锌和白蛋白含量与对照组差异显著（P〈0．05）。试验组血清碱性磷酸酶、总蛋白含量与对照组差异显著（P〈0．05）,各处理组间尿素氮差异不显著（P〉0．05）。结论为在40日龄吉戎兔饲粮中添加80mg/kg蛋氨酸锌适宜。     

肺动脉高压综合征发病过程中肉鸡血清和肺脏iNOS和cNOS活性变化

常规饲养条件喂养的大群AA肉鸡，按临床症状分为肺动脉高压组（M组），肺动脉高压腹水组（S组）和正常对照组（C组）。分别测定21、28、35和42日龄S组、M组和C组肉鸡的腹水心脏指数（AHI）、全心与体重比（WH／BW）、平均肺动脉高压（mPAP）、血清一氧化氮（NO）水平、肺脏和血清cNOS和iNOS活性。试验结果表明：（1）S组和M组全心与体重比值（TV／BW）以及S组血清NO水平均从28日龄起显著或极显著高于C组（P〈O．01或P〈0．05）；（2）S组肺组织cNOS水平显著或极显著低于C组（P〈0．01或P〈0．05）；（3）S组肺组织iNOS在21、35和42日龄显著或极显著高于C组（P〈0．01或P〈0．05）；（4）S组从28日龄起血清中cNOS和iNOS与C组差异显著或极显著（P〈0．01或P〈0．05）；（5）正常对照组肉鸡血清中iNOS活性在21、35和42日龄均显著或极显著低于血清中cNOS活性（P〈0．01或P〈0．05）。此研究结果提示cNOS和iNOS活性的变化与PHS发病机理有着密切的关系，并在其中发挥着重要的作用。     

甘露寡糖、中药和微生态制剂对肉鸡抗氧化性能的影响

1992只1日龄AA肉鸡随机分为4个处理组,饲喂四种不同的日粮。42日龄测定各组肉鸡组织及血清抗氧化指标的水平。结果表明:(1)除心脏和血清外,各试验组MDA含量均与IV组差异显著(P<0.05)。(2)肝脏中SOD变化较明显,各试验组均高于IV组,且差异显著(P<0.05)。心脏各组之间差异不显著。(3)心脏GSH-Px含量以III、II组较高,且均与IV组差异显著。血清以II组最高,且与其他各组之间差异显著(P<0.05)。(4)心脏T-AOC含量变化较大,各试验组均高于IV组,且差异显著(P<0.05)。血清以II组最高,且与其他试验组差异显著(P<0.05)。     

高锌对艾维菌肉鸡血液病理学的系统研究

试验将1日龄艾维菌肉鸡健雏200只随机分为4组,分别喂以基础日粮（Zn 100mg／kg,A组）、高锌日粮Ⅰ（Zn1500mg／kg,B组）、高锌日粮Ⅱ（Zn2000mg／kg,C组）和高锌日粮Ⅲ（Zn2500mg／kg,D组）,试验期为7周。结果表明：B组血清碱性磷酸酶（AKP）活性显著升高（P〈0．05）,D组显著降低（P〈0．05）;血清碱性磷酸酶的同工酶亦受到不同程度的影响;谷丙转氨酶（GPT）、淀粉酶（AMY）活性各试验组显著升高（P〈0．05）;肌酸激酶（CK）活性在试验初期升高,中期不同程度降低（P〈0．05）,试验结束时与对照组无显著差异（P〉0．05）;血清总蛋白（TP）、球蛋白（GLB）含量随锌水平的升高而升高,白蛋白（ALB）含量下降,但均与对照组比较差异不显著（P〉0．05）;血清锌含量随饲料锌水平增高而显著升高（P〈0．05）;血清中钙、磷含量则与饲料锌水平呈负相关。     

高赖氨酸水稻在肉鸡饲粮中应用效果的研究

高赖氨酸水稻;肉鸡;应用效果摘要：为研究不同比例高赖氨酸水稻替代玉米对肉用仔鸡生产、屠宰性能和部分血液生化指标的影响,选用150只1日龄AA肉鸡,分为3组,每组2个重复,每个重复25只鸡,分为前期（0～21d）和后期（22～42d）两个阶段饲养。对照组采用玉米一豆粕型日粮;试验组分别为高赖氨酸水稻替代40％、100％玉米组．分别在21日龄、42日龄测定各组肉鸡的生产性能、屠宰性能及部分血液生化指标。生长试验结果表明：前期高赖氨酸水稻替代40％玉米组肉鸡的平均日采食量、平均日增重、料重比与对照组差异不显著（P〉0．05）,高赖氨酸水稻替代100％玉米组肉鸡的平均日采食量、平均日增重与对照组差异不显著（P〉0．05）;后期高赖氨酸水稻替代40％玉米组和替代100％玉米组肉鸡的平均日采食量、平均日增重、料重比与对照组差异不显著（P〉0．05）。屠宰试验结果表明：前期试验组胸肌率有显著提高（P〈0．05）,全净膛率、腿肌率、腹脂率与对照组无显著差异（P〉0．05）;后期腿肌率有显著提高（P〈0．05）,全净膛率、腿肌率、腹脂率与对照组无显著差异（P〉0．05）。血液生化指标测定结果表明：前期对照组和试验组血液指标除碱性磷酸酶含量和总胆固醇含量有显著差异外（P〈0．05）,其他指标无显著差异（P〉0．05）;后期对照组和试验组各个血液指标间均无显著差异（P〉0．05）。结论：高赖氨酸水稻部分或完全代替玉米饲养肉鸡是可行的。     

免疫增强剂硒对雏鸡免疫功能的影响

300只1日龄南海黄雏鸡随机分为5组，Ⅰ－Ⅳ组为加硒试验组，Ⅴ组为不加硒对照组。全部试验鸡均饲喂不缺硒饲料（含硒0．18mg/kg)，并以饮水方式进行新城疫首免和2免。Ⅰ、Ⅱ、Ⅲ、Ⅳ组分别于2次免疫前2d起连续3d以亚硒酸钠饮水给硒0．25、0．5、0．75、1．0mg/kg。结果表明，各组平均血清硒含量变化与饮水给硒剂量一致；Ⅰ－Ⅳ组的新城疫HI抗体滴度显著或极显著地高于Ⅴ组（P＜0．05或P＜0．01）；Ⅲ、Ⅳ组体重显著或极显著地高于Ⅴ组（P＜0．05或P＜0．01）；各加硒试验组特别是Ⅲ组在红细胞Ⅰ型补体受体（CR1）活性较Ⅴ组高；各组免疫器官指数未出现显著性差异。     

发酵乳酸杆菌对肉鸡血清抗氧化性能及肠道挥发性脂肪酸（VFA）的影响

旨在研究添加不同剂量的发酵乳酸杆菌F-6对肉鸡血清抗氧化性能及肠道VFA含量的影响。选择健康的1日龄AA肉仔鸡240只,称重后随机分为4组,各组肉仔鸡的初始体重差异均不显著（P〉0.05）。各组肉仔鸡基础日粮一致,3个试验组在饮水中添加发酵乳酸杆菌F-6,添加剂量分别为2.0×10~5、2.0×10~6、1.0×10~7CFU/m L,对照组肉仔鸡不饲喂发酵乳酸杆菌。于21日龄及42日龄时,分别测定各组肉鸡血清中的MDA和SOD含量,以及肠道中VFA含量。结果表明：21日龄时,试验3组肉鸡血清中的SOD含量显著高于对照组（P〈0.05）;42日龄时,试验2组和3组肉鸡血清中的SOD含量也显著高于对照组（P〈0.05）。21日龄和42日龄时,各试验组肉鸡盲肠及回肠中的乙酸和总挥发性脂肪酸（TVFA）含量均显著高于对照组（P〈0.05）;除试验1组外,其他各试验组肉鸡的回肠及盲肠丁酸含量均显著高于对照组（P〈0.05）。综上提示,发酵乳酸杆菌F-6能够显著提高肉鸡的血清抗氧化性能及肠道部分VFA含量,其具有开发为新型饲料益生菌添加剂的应用前景。     

复方中药“禽康散”对人工感染新城疫病毒肉鸡血清免疫球蛋白及新城疫抗体效价的影响

10日龄的健康艾维茵肉仔鸡250只,随机分为5组。21日龄时除阴性对照组（Ⅳ组）外均用新城疫病毒（Newcastle disease,virus,NDV）强毒株攻毒,各治疗组（Ⅰ～Ⅲ组）在22～25日龄饲料中分别添加0．5％、1.0％、2．0％的复方中药“禽康散”,第Ⅳ、Ⅴ组（阳性对照组）不用药。在攻毒前1d和攻毒后1、3（用药后2d）、7（停药后2d）、15（停药后10d）d观察血清免疫球蛋白及新城疫抗体效价的变化。结果显示：Ⅴ、Ⅱ组血清IgG在攻毒15d（停药10d）时与Ⅲ、Ⅳ、V组差异极显著（P〈O．01）;Ⅰ～Ⅲ组血清IgA浓度在攻毒后3、7d均明显高于第V组（P〈0．05或0．01）,以1％治疗组效果最佳;各组之间血清中IgM含量无显著差异（P〉0．05）。Ⅴ～Ⅲ组新城疫抗体效价在攻毒7d后各阶段均高于阳性对照组（P〈0．05或0．01）,以第Ⅲ组最佳。结果表明,日粮添加1．0％～2．0％质量分数的“禽康散”能明显增加血清中IgG、IgA含量和新城疫抗体效价,从而提高机体体液免疫功能,达到提高机体抗NDV的能力。     

内皮素-1对肉鸡腹水综合征发生发展的影响

利用放射免疫分析方法，分别测定了35日龄正常组、轻度腹水组、重度腹水组肉鸡血浆内皮素-1（ET-1）、心钠素（ANP）的含量以及心、肝、肺、肾等组织ET-1的含量，并测定了腹水心脏指数（AHI）、平均右心室压（mRVP）和平均肺动脉压（mPAP）；同时还用硝酸还原酶法测定了血清中一氧化氮（NO）的水平。结果发现，随腹水程度的加深，mRVP、mPAP、AHI极显著（P〈0．01）升高，肉鸡血浆ET-1、ANP和组织中ET-1的含量以及血清NO浓度也显著（P〈0．05）或极显著（P〈0．01）升高，且重度腹水组高于轻度腹水组；另外还发现，血浆ET-1、ANP与mPAP、AHI以及心脏ET-1含量之间相关性显著（P〈0．05），而血清NO含量与上述指标之间无明显的相关性（P〉0．05）。结果表明ET-1、ANP、NO均参与了肉鸡AS的发生和发展过程并在其中起着重要作用，其中ET-1、ANP与肉鸡发生腹水的程度有密切的关系。     

Knowledge,attitude, and practices on usage,disposal, and effect of plastic bags on sheep and goats

The objective of this study was to evaluate knowledge, attitudes, and practices of people in the Nairobi and Kajiado Counties, Kenya, on the usage, disposal, and effect of plastic waste on sheep and goats (shoats). A semi-structured questionnaire was used to collect data from 384 respondents in four communities in the two counties. Most of the people irrespective of their age, occupation, and educational status used plastic bags of some type on a daily basis. A high proportion of the respondents (37.0%, 142) used plastic bags because of the low cost. Approximately, 79.1% (304) disposed used plastic bags in open dumps. A total of 147 (38.3%) households kept shoats. Out of these, 38.1% (56) purchased feed and also allowed their animals to roam. Most of them (45.3%, 174) thought that lack of feed for the animals was the main reason why shoats roam and scavenge at refuse dump sites and road sides. A large proportion of the respondents (44.5%, 143) mentioned death of animals as the ultimate consequence of ingestion of waste plastic bags. Though, the respondents were aware that indiscriminate disposal of used plastic bags could result in death of the animals from which they derive their livelihoods, they nevertheless continued with the practice. There is a need for a paradigm shift in the way and manner plastic bags are used and disposed.     

Ticks on crested francolins, Francolinus sephaena, and on the vegetation on a farm in Limpopo Province, South Africa

Ticks were collected at approximately bi-monthly intervals between June 1996 and June 1997 from crested francolins, Francolinus sephaena, and from the vegetation on a mixed cattle and wildlife farm in Limpopo Province, South Africa. The birds were infested with the immature stages of 13 tick species, of which Amblyomma hebraeum, Amblyomma marmoreum and Hyalomma marginatum rufipes were the most numerous and prevalent. Ten ixodid tick species were collected from the vegetation, of which the immature stages of Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) decoloratus and Rhipicephalus evertsi evertsi were the most numerous. No adult ticks were collected from the birds and only two from the vegetation. The restricted home range of crested francolins implies that they could serve as a source of tick infestation only for other animals within the same habitat as the birds.     

Effect of feeding corn naturally contaminated with aflatoxin on feed efficiency, on physiologic, immunologic, and pathologic changes, and on tissue residues in steers

Two of 3 groups of Holstein-Friesian steers (groups II and III; n = 5 each) were fed a ration containing corn naturally contaminated with 800 ng of aflatoxin/g. The other group of steers (group I; n = 5) was fed a ration containing noncontaminated corn. The respective rations were fed for 17.5 weeks, except the ration given to group III; the latter's first diet (contaminated with aflatoxin) was changed to a noncontaminated diet after 15 weeks, continuing for the remaining 2.5 weeks. All steers were killed and tissues and fluids were obtained for aflatoxin analysis. Although aflatoxin B1 and M1 could be detected in blood and urine at several sampling times during the experimental period in groups II and III steers (given the diets containing aflatoxin), there appeared to be no effects on body weight gains and immune phenomena, such as lymphoblastogenesis and antibody production, but there was a waning of the delayed cutaneous hypersensitivity in steers given aflatoxin-contaminated diets. In group III animals (diet was changed to noncontaminated ration at 15 weeks), aflatoxin B1 and M1 disappeared from urine before they were slaughtered. All tissues and fluids, except the rumen contents from these group III steers, were void of detectable aflatoxins B1 and M1 at necropsy. The concentrations of aflatoxin B1 in the rumen content of the latter steers were low. All tissues collected at necropsy from the group II steers fed the aflatoxin diet throughout the 17.5 weeks had detectable aflatoxins B1 or M1 present.     

Effects of sire growth potential, growing-finishing strategy, and time on feed on performance, composition, and efficiency of steers.

Beef production systems that increase use of unharvested forages and use animals with greater potential for gain affect age and size of animals placed on a finishing regimen. This experiment was conducted to evaluate effects of genetic potential for gain, age at the start of a finishing period, and time on feed on composition, quantity, and quality of beef produced and efficiency of production during finishing. Crossbred cows were bred by AI to Charolais or Line 1 Hereford bulls that represented potentially high (HG) or moderate growth (MG) rates, respectively, to produce spring- or fall-born calves. Steer calves from these matings were placed on an individually fed finishing diet at three ages (A). Spring-born steers were started at 6 or 18 mo of age (A6 and A18), and fall-born steers were started at 12 mo of age (A12). Slaughter times (T) were at 0, 90, 180, and 270 d for A6; 68, 136, and 204 d for A12; and 0, 45, 90, and 135 d for A18. Data collected on each animal included feed intake, growth, chemical composition of the complete body and carcass, and quantitative and qualitative assessment of the meat produced. Four steers of each sire group were slaughtered in each of the 11 A-T treatment groups, and the experiment was repeated for 2 yr in the A12 groups and 3 yr in the A6 and A18 groups (n = 237). Steers sired by HG bulls were larger and produced larger carcasses and more carcass protein than MG-sired steers (S, P < .05 or .01). Steers sired by MG bulls were fatter, had higher quality grades, and accumulated fat at a faster rate than HG-sired steers, and this effect was greater in older steers (G and GA, P < .05 or .01). Sire growth potential did not affect gain, intake, live weight efficiency, tenderness, or taste panel scores (P > .2). Steers sired by HG bulls were more efficient at producing carcass weight and carcass protein at A12 and A18 than were MG-sired steers. At the end of the finishing period, older (A18), HG-sired steers were too large with insufficient fat by current industry standards, and younger (A6), MG-sired steers were too small. Our conclusions are that both HG- and MG-sired steers can produce acceptable carcasses for current market standards with comparable efficiencies of live-weight gain, but the growing and finishing strategy must be adapted to the genotype.