“京红1号”父母代公鸡生长规律与精液品质相关性的研究

试验以120只"京红1号"父母代蛋种公鸡为研究对象,每周测1次体重,24周龄后每2周测1次,测至64周淘汰;每周测量1次胫长,测至18周龄;24周龄开始检测精液品质,包括排精量、精子活力等指标,每2周测1次,连续检测6次。结果表明:试验公鸡体重在育雏育成期生长旺盛,胫长持续增加;利用Logistic、Gompertz、Richaid模型对公鸡体重进行生长拟合,Gompertz模型拟合度最高(R2=0.9971);对育雏育成期的体重与胫长进行相关性分析,两者呈中等强度相关,各周龄相关系数(r)在0.49~0.68之间;对公鸡体重、胫长等生长指标和排精量、活力等繁殖性能指标进行相关性分析,生长指标和繁殖性能指标的相关性小(r≤0.161);以23周体重和体胫比分别将公鸡分4组,各组鸡群的体重和体胫比分组差异显著时,繁殖性能差异不显著,因而不能在育雏育成期通过公鸡体重或胫长的测量选留出繁殖性能较强的公鸡。     

仙居鸡早期肉用性状的测定与遗传力估计

通过测定仙居鸡体重、体尺、屠宰和肉品质性状,研究其肉用特性。试验用12个公鸡家系的720只健康雏鸡(公、母各半),进行为期12周的饲养。每周测定个体重,12周龄时每个家系取5只公鸡、5只母鸡测定其体尺、屠宰性能和肉品质。结果表明:2周龄后公鸡体重均极显著大于母鸡(P<0.01),12周龄公、母体重分别为858.9g和719.5g;12周龄公鸡的体斜长、龙骨长、胫长、胫围都显著大于母鸡(P<0.05);公鸡的屠体率、半净膛率、胸肌率、头率、爪率、心率、肝率等指标均极显著大于母鸡(P<0.01),而肌、腺胃率则是母鸡极显著大于公鸡(P<0.01);公鸡胸肌剪切力显著大于母鸡(P<0.05)。     

二郎山山地鸡两个品系早期生长及屠宰性能的比较

为了更好地指导二郎山山地鸡的选育工作,试验对二郎山山地鸡SD02、SD03两个品系的早期增重以及13周龄屠宰性能进行了比较。结果表明:SD02品系在6周以前饲料报酬以及生长速度都落后于SD03品系,而6周后则超过了后者;屠宰性能方面,除了公鸡的腿肌率、母鸡的屠宰率差异显著外(P0.05),其余指标差异均不显著(P0.05)。同时,两个品系的母鸡腹脂率均远远高于同品系的公鸡。     

振宁矮脚黄鸡新品系培育

将含有dw基因的纯系黄鸡导入宁波市振宁牧业有限公司选育的地方品种鸡群(R系)内,培育出新的含有纯合dw基因品系K系。选育出的振宁矮小型黄鸡品系K系,体型外貌一致,胸肌丰满,鸡肉光滑,毛孔细小,胫短;公鸡胫长6.0 cm以下,母鸡胫长5.5 cm以下;公鸡16周龄体重在1.70 kg以上,母鸡在1.25 kg以上。     

dw基因对矮小型农凤鸡体型性状的影响

以农凤鸡为研究对象,通过测交试验分析测交后代中矮小型和正常型鸡18周龄的体型性状指标。结果表明:矮小型鸡与正常型鸡相比,公鸡体重轻21.5%,母鸡体重轻17.7%,差异显著(P0.05);公鸡胫长短20.9%,母鸡胫长短20.8%,差异极显著(P0.01);公鸡胸宽窄4.7%,母鸡胸宽窄11.0%,差异极显著(P0.01);公鸡胸深浅20.3%,母鸡胸深浅13.5%,差异极显著(P0.01);公鸡体斜长短14.2%,母鸡体斜长短12.3%,差异极显著(P0.01)。结论:dw基因使矮小型鸡体型小于正常型鸡、母鸡体型小于公鸡体型。     

乌蒙凤鸡肉用专门化品系选育初探

本研究旨在对不同类型乌蒙凤鸡的生长性能进行测定分析,为乌蒙凤鸡肉用专门化品系的选育奠定基础。实验测定了乌蒙凤鸡不同羽色(黄羽、麻羽)、肤色(乌骨、普通)及不同羽色与肤色的组合(黄羽普通、黄羽乌骨、麻羽普通、麻羽乌骨)4个类型鸡群4～24周龄的生长性能。结果表明:按羽色或肤色的单一性状进行划分,乌蒙凤鸡黄羽和麻羽、普通和乌骨之间生长性能差异不显著;黄羽公鸡4～16周龄生长性能显著高于麻羽公鸡;不同羽色和肤色的公鸡生长性能均高于母鸡(P<0.01);黄羽普通鸡群体生长性能高于其他类型鸡群。根据分析测定结果,建议将黄羽普通鸡作为乌蒙凤鸡肉用专门化品系选育的候选类型。     

信宜怀乡鸡生长和肉用性能测定结果

笔者选用信宜怀乡鸡商品雏120只,分为公、母2个处理组,每个处理组有4个重复,每个重复15只,进行了0周龄~16周龄的饲养试验,旨在探讨怀乡鸡的生长与肉用性能。结果表明,16周龄公、母鸡体重分别为1744 g和1590 g,差异显著(P0.05);16周龄屠宰性能,总体趋势是公鸡大于母鸡,差异显著(P0.05),而腹脂重、肌间脂肪宽和皮下脂肪厚为母鸡大于公鸡,差异显著(P0.05);16周龄肌肉品质,胸、腿肌的粗蛋白含量均是公鸡显著高于母鸡(P0.05),而粗脂肪含量均是母鸡高于公鸡,差异显著(P0.05)。     

边鸡新品系双向选育进展

实验旨在对边鸡新品系6个世代的生长性能进行测定,并在第5世代进行PCR-RFLP分析,检验双向选择效果。结果显示:各世代从初生到16周龄,快长系(AA)公鸡的体重均极显著高于慢长系(GG)公鸡,AA母鸡的体重均极显著高于GG母鸡。AA公鸡16周龄由1世代1 600.37 g增加到6世代2 107.62 g,提高了31.70%,AA母鸡16周龄由1 205.18 g增加到1 592.49 g,提高了32.14%;GG公鸡16周龄体重由1世代的1429.30g降低到6世代的1078.13g,减少了24.57%,GG母鸡16周龄体重由1056.03g降低到814.12 g,减少了22.91%。AA公母鸡的生长曲线呈上升趋势,GG公母鸡的生长曲线呈下降趋势。快长系个体和慢长系个体的基因型纯合率为100%。结果表明,以分子标记辅助育种为基础的边鸡新品系双向选择效果明显。     

固始鸡三系配套组合生长性能及屠体品质测定

以固始鸡G系公鸡×AH系母鸡、固始鸡G系公鸡×DH系母鸡和固始鸡G系公鸡×MH系母鸡为研究对象,通过配合力测定比较其生长性能、屠宰性能及肉品质等的优劣筛选出最佳母本配套品系。结果表明:GAH组合生长速度最快,GAH组合16周龄公鸡比GDH组和GMH组重170～182 g,母鸡比另外两组重119～120 g,且料重比最低。16周龄除胫长和胸深外GAH组公鸡的其他体尺指标均显著(P0.05)大于GDH和GMH两组。三个配套组合试验鸡16周龄屠体率大于85%、全净膛率大于65%,产肉性能良好。三个组合中,GAH组半净膛率和腿肌率大于其他两组且腿肌干物质和肌内脂肪含量相对较高,GDH组胸肌干物质和肌内脂肪含量相对较高,但GDH组剪切力最大。总体而言,GAH组生长发育和体尺指标在整个饲养期间显著高于另外两个组合,且其屠宰性能优,综合评价GAH组的生长最快,肉用价值最高。     

人工授精技术应用在肉鸡育种工作中的试验

鸡人工授精技术已为不少单位采用,尤其是在蛋鸡的生产中应用较为广泛,而在肉种鸡特别是在肉鸡育种工作中较少采用,报道也少。我们于1982年起在这方面进行了探索,并在“七五”攻关项目《优质黄羽肉鸡品系选育及配套研究》的品系选育中,运用人工授精技术进行了四个品系的始祖建系,取得了满意的效果。一、材料与方法1、材料:经羽性测试的鹿苑快羽系(L_1)、慢羽系(L_2)和海佩科快羽系(H_4)、慢羽系(H_3)四个基础群。2、方法:在四个基础群中,通过采精训练,选择具有各自品种特征且采精良好的公鸡各1羽作为系祖.L_1为108号公鸡,L_2为115号公鸡,H_4为148号公鸡,H_3为144号公鸡。选择产蛋好且具有品种特征的母鸡作种母鸡,计有:L_1系31羽,L_2系23羽,H_4系39羽,H_3系18羽。公鸡精液根据采精量作2～3倍稀释,每羽母鸡的输精量为0.05毫升。开始时连续输精2天,以后每周输精2次。母鸡编号后实行一鸡一笼单独饲养。种蛋每2周入孵1次,共入孵4次。二、结果与讨论     

中国猪瘟兔化弱毒株（C-株）兔脾组织毒主要保护性抗原E2（gp55）基因序列分析

利用反转录（RT）及套式PCR（N-PCR）方法扩增了中国猪瘟兔化弱毒株（C-株）兔脾组织毒主要保护性抗原E2（gp55）基因，成功地将其克隆并测定了核苷酸序列，与国内外已发表的猪瘟病毒（HCV）E2基因序列比较的结果是C-株兔脾毒与C-株细胞（SK6）毒、C-株疫苗（犊牛睾丸细胞，HCLV-C）毒、HCV-SM株（石门）毒、Brescia株（荷兰）毒、Alfort株（德国）毒的E2核苷酸序列同源性分别为98.87％、98.34％、94.58％、91.00％、80.78％；氨基酸同源性分别为98.95％、97.37％、94.22％、91.60％、89.23％。对C-株兔脾毒与C-株细胞毒、经典强毒及国内流行野毒E2上的A、B、C三个中和性抗原区的氨基酸组成进行了比较，其结果为C-株兔脾毒与C-株细胞毒的差异很小甚至没有差异，而与流行野毒及经典强毒在B、C区有较大的差异。我国经典强毒石门毒与国内80年代和90年代流行毒之间有明显的差异，表明我国猪瘟流行毒株发生了变化。     

Effect of Hypertension on the Occurrence of Micro-hemorrhage in the Pancreatic Islet of Dahl Salt-sensitive Rats

The effect of hypertension on the occurrence of micro-hemorrhage in the pancreatic islet, known to be observed in Sprague-Dawley (SD) rats spontaneously, and endothelial markers were investigated in male Dahl-Iwai salt-sensitive (DIS, derived from SD rats), salt-resistant (DIR), and SD rats. DIS and DIR rats were fed 8% NaCl-containing diet to induce hypertension, with blood pressure measurement once a week, euthanized at 6, 8, or 12 weeks of age, and subjected to the measurement of plasma nitric oxide (NO) and von Willebrand factor (vWF) concentrations combined with histopathological examinations and immunohistochemical detections of vWF in the pancreas and kidney. As a result, hypertension was observed from 7 through 12 weeks of age in DIS rats. At 12 weeks of age, only DIS rats showed decreased plasma NO and increased vWF, indicating endothelial abnormality in the body. Histopathologically, micro-hemorrhage in the islet was observed with a similar incidence and severity in SD and DIS rats aged 12 weeks, and vWF was immunohistochemically localized in the islet endothelium with similar reactivity between age-matched SD rats. On the other hand, in the kidney, glomerular sclerosis was observed in DIS rats aged 12 weeks and accompanied broad stainability of vWF in the sclerotic glomerulus, including endothelium. In conclusion, there was no enhancement/exaggeration in the micro-hemorrhage in the pancreatic islet of hypertensive DIS rats in comparison with that in SD rats under the present experimental conditions. It is suggested that hypertension is not related to the occurrence of islet micro-hemorrhage, spontaneously observed in SD rats.     

中国美利奴羊(新疆军垦型)品系间羊毛理化性能及性状相关分析

为研究中国美利奴羊(新疆军垦型)品系间的毛品质特点,以超细毛品系、A品系、B品系、毛用多胎品系和肉用多胎品系为试验对象,测定毛纤维的主要理化性能,分析各品系羊的毛纤维特点,并作相关分析。结果表明,A品系羊毛自然长度最长;超细毛品系羊毛纤维直径显著低于其它品系(P＜0.05),其羊毛卷曲度显著高于其它品系(P＜0.05);B品系污毛量最高,肉用多胎品系污毛量显著低于其它品系(P＜0.05)。毛用多胎品系净毛率最高,但各品系间净毛率差异不显著(P＞0.05)。相关分析结果表明,羊毛细度与卷曲度呈极显著负相关(P＜0.01),细度与污毛量呈显著正相关(P＜0.05);卷曲度与污毛量呈显著负相关(P＜0.05),卷曲度与自然长度呈极显著负相关(P<0.01);污毛量与自然长度呈极显著正相关(P＜0.01);自然长度与净毛率呈显著正相关(P＜0.05)。说明各品系羊的毛品质特点与培育目标一致,其中,超细毛品系羊毛综合品质优良。     

商品代白羽乌骨鸡早期肉用性能的观测

对商品代白羽乌骨鸡早期肉用性能进行了观测，并以泰和鸡、黄羽乌骨鸡为对照组。结果表明：１０周龄体重，白羽乌骨鸡为１０３１．５ｇ、黄羽乌骨鸡为８５４．６ｇ、泰和鸡为５０３．０ｇ，三个鸡种间差异极显著。三个鸡种饲料转化比、屠宰率差异不显著。     

Identification of the antigenic components of the virulent Mycoplasma gallisepticum (R) in chickens: their role in differentiation from the vaccine strain (F)

The antibody response to different proteins of Mycoplasma gallisepticum (MG) was studied in chickens experimentally infected with virulent MG R strain. The chickens were challenged at 8 weeks of age by the intranasal route. Each cockerel received 1.3 X 10(6) colony-forming units (CFU). MG strains (R and F) were banded by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). The banding pattern was distinctively different between the two strains in the range of 92.5 to 200 kilodaltons (kD). Chicken sera collected at different times following challenge were analyzed by Western blot to determine the patterns of antibodies raised to specific MG proteins (R versus F strains). Early in infection (2 weeks postchallenge), antibodies to 60-kD and 75-kD polypeptides of MG R strain were produced. Subsequently (greater than or equal to 4 weeks postchallenge), antibodies recognized a larger number of MG antigens in both strains. The immunoblot patterns remained the same in the period 8-11 weeks postinfection in each of the two strains; however, the patterns were different when the two strains were compared. The early response recognized the 75-kD protein in the R strain while it recognized the 80-kD protein in the F strain. The late response recognized the 130-kD protein and the protein slightly heavier than 200 kD in the R strain. These two bands did not appear in the immunoblot performed against the F strain of MG. Electroeluted protein of MG R strain, namely adhesin (75 kD), showed a hemagglutination activity (HA) on chicken red blood cells. With the appearance of antibodies specific to the 60-kD and 75-kD polypeptides, there was a significant rise in hemagglutination-inhibition geometric mean titer of chicken sera.     

Duration of immunity induced in chickens by an attenuated live Salmonella enteritidis vaccine and an inactivated Salmonella enteritidis/typhimurium vaccine

The aim of this study was to examine the duration of immunity of different vaccination schemes using the S. enteritidis live vaccine Gallivac Se and the S. enteritidis-S. typhimurium inactivated vaccine Gallimune Se+St. Three groups of Lohman Brown chickens were used. Group one was vaccinated three times orally with Gallivac Se at weeks one, seven and 13 of age. Group two was vaccinated twice orally with Gallivac Se in weeks one and seven and once i.m. with Gallimune Se+St in week 14 of age. A third group was not vaccinated and served as the control group. Eight randomly selected chickens from each of the three groups were challenged with a nalidixic acid resistant S. enteritidis PT4 strain in weeks 24, 51 and 71 of age and the same number of animals were challenged with a S. typhimurium DT 104 strain in weeks 26, 54 and 73 (75) of age.The chickens were euthanised seven days post challenge and the number of challenge strain organisms (log10 cfu) in the liver and on caecal mucosa was determined.The quantitative investigation of the challenge strain in the liver and caecal mucosa revealed a statistically significant (p < 0.05) lower challenge strain burden in the vaccinated groups compared with the non-vaccinated control group up to week 71 (73) of age. The protective effects were demonstrated for both challenge strains.     

中国美利奴羊（新疆军垦型）品系间毛细度分析

羊毛纤维直径、细度标准差与细度离散是体现毛细度的重要参数。以中国美利奴羊（新疆军垦型）超细毛品系、A品系、B品系、毛用多胎品系和肉用多胎品系为试验对象,测定毛纤维直径、细度标准差和细度离散系数,分析各品系羊毛细度特点并作相关分析。结果表明,超细毛品系羊毛纤维直径最小,其毛纤维直径、细度标准差和细度离散系数显著低于其它品系（P〈0.05）。毛纤维直径随着年龄的增加逐渐变大,细度标准差和细度离散随着年龄的增加变化不显著。相关分析表明,毛纤维直径与年龄及细度标准差呈极显著正相关（P〈0.01）,细度标准差与细度离散呈极显著正相关（P〈0.01）。说明纤维直径越小,细度标准差越小,毛品质越好,各品系羊的毛细度特点与培育目标一致,其中,超细毛品系羊毛品质最好。     

用SDS—PAGE进行鸡败血霉形体结构蛋白分析

利用SDS－PAGE方法对禽败血霉形体R，S6，F株和6株国内分离株进行了结构蛋白比较分析，电泳凝胶染色扫描结果显示，各株之间结构蛋白差异较大，R，S6株P64蛋白表达量较高，D9604株与其相似性较高，D9601，D9603和D9605与F株均有一条特异的75kDa条带，提示我国分离的MG强毒株可能存在着多样性。     

Comparison of Susceptibility of Five Cutthroat Trout Strains to Myxobolus cerebralis Infection

Abstract

Susceptibility to infection by the myxosporean parasite Myxobolus cerebralis was compared among strains of cutthroat trout Oncorhynchus clarki in two separate exposure tests in the laboratory. In both tests, each strain was exposed to 1,000 triactinomyxons/fish for 2 h in 8.0 L of water. In the first test, three strains of 10-week-old cutthroat trout were compared: two strains of Bonneville cutthroat trout O. c. utah (Bear Lake and southern Bonneville strains) and Yellowstone cutthroat trout O. c. bouvieri. In the second test, these strains plus Snake River fine-spotted cutthroat trout O. c. subsp. and Colorado River cutthroat trout O. c. pleuriticus were exposed at either 5 or 10 weeks of age. The prevalence of the M. cerebralis infection was determined by single-round polymerase chain reaction (PCR) assay 5 weeks after exposure. In the first test, the prevalence was significantly lower in the Bear Lake strain of Bonneville cutthroat trout (78.5%) than in the Yellowstone (97.8%) or southern Bonneville (100%) strains when exposed at 10 weeks of age. In the second test, the Bear Lake strain also had significantly lower infection rates after exposure at 5 (54%) or 10 weeks (82%) of age than the other four strains, which did not differ from each other (94–100%). The severity of the infection was also significantly reduced in Bear Lake Bonneville cutthroat trout, as suggested by the strength of the product of the single-round PCR assay. These results suggest that intraspecific differences in susceptibility to M. cerebralis infection exist, further supporting the need to maintain the genetic diversity among subspecies and geographic variants of cutthroat trout.     

Comparison of a tissue-culture virus-neutralization test and the enzyme-linked immunosorbent assay for measurement of antibodies t infectious bronchitis

Two serological tests, the virus-neutralization (VN) test in tissue culture using a tissue-cell-adapted virus and the enzyme-linked immunosorbent assay (ELISA), were compared to detect antibodies against Massachusetts 41 and Connecticut 46 strains of Infectious Bronchitis Virus (IBV). The VN test was conducted in wells of microplates by the usual procedure. The two strains of IBV were adapted after 20 serial passages to induce CPE in 24 hours in chickens embryos kidney cells (CEKC). The ELISA test was carried out using partially virus following ultracentrifugation of each stain of IBV as antigen. The ELISA test detected higher geometric mean antibody titers (GMT) against both strains of IBV than did the VN test. One hundred four serum samples taken at 1, 3, 5, 9, 22, 24, and 26 weeks of age from a flock of chickens vaccinated with the Mass strain three times and the Conn strain of IBV two times during the growing period showed higher antibody titer responses to the Conn 46 than to the Mass 41 strain. Maternal antibodies in chicks one week of age were readily detected by the ELISA test, whereas low or insignificant titers were found by the VN test. Sera of vaccinated chickens collected following challenge with Mass 41 or Conn 46 strain of IBV showed that the ELISA was more sensitive and showed higher titers than did the VN test. Although the VN test showed no rise in GMT in the same sera tested with the heterologous virus, the ELISA showed a slight increase or cross-reaction. The serum samples from the unchallenged control group showed no change in GMT with either test or IBV strain.