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1.
本试验旨在通过研究饲粮苏氨酸水平对1～21日龄黄羽肉鸡生长性能、胴体品质、脂肪代谢和免疫功能的影响,以确定1～21日龄黄羽肉鸡适宜的苏氨酸需要量。试验选用1日龄快大型岭南黄羽肉鸡雏鸡2 000只,按体重相同原则随机分为5组,每组8个重复(公母各占1/2),每个重复50只鸡。5个组的试验鸡分别饲喂含0.60%(基础饲粮)、0.67%、0.74%、0.81%和0.88%苏氨酸的饲粮,试验期为21 d。结果表明:1)饲粮苏氨酸水平显著影响黄羽肉鸡公鸡、母鸡的末重、平均日增重、平均日采食量和料重比(P0.05)。0.88%苏氨酸水平组黄羽肉鸡母鸡平均日增重和平均日采食量最高,0.74%苏氨酸水平组黄羽肉鸡公鸡平均日增重和平均日采食量最高。根据生长性能指标和回归分析结果,确定黄羽肉鸡母鸡饲粮苏氨酸最适水平为0.81%,黄羽肉鸡公鸡饲粮苏氨酸最适水平为0.79%。2)饲粮苏氨酸水平显著影响黄羽肉鸡公鸡、母鸡的全净膛率、半净膛率和腿肌率(P0.05)。0.88%苏氨酸水平组黄羽肉鸡母鸡半净膛率和全净膛率最高,0.74%苏氨酸水平组黄羽肉鸡母鸡腿肌率最高;0.81%苏氨酸水平组黄羽肉鸡公鸡半净膛率最高,0.74%苏氨酸水平组黄羽肉鸡公鸡全净膛率和腿肌率最高。根据胴体品质指标和回归分析结果,确定黄羽肉鸡公鸡饲粮苏氨酸最适水平为0.77%,黄羽肉鸡母鸡饲粮苏氨酸最适水平为0.88%。3)饲粮苏氨酸水平显著影响黄羽肉鸡公鸡、母鸡的胸腺指数(P0.05),其中0.88%苏氨酸水平组黄羽肉鸡公鸡和母鸡胸腺指数最高。4)饲粮苏氨酸水平对黄羽肉鸡母鸡血清中甘油三酯(TG)、免疫球蛋白G(IgG)、白细胞介素-6(IL-6)和胰岛素(INS)含量有显著影响(P0.05),其中0.88%苏氨酸水平组血清中TG和INS含量最低,0.88%苏氨酸水平组血清中IL-6和IgG含量最高;饲粮苏氨酸水平对黄羽肉鸡公鸡血清中低密度脂蛋白、INS、IL-6和IgG含量有显著影响(P0.05),其中0.88%苏氨酸水平组血清中LDL和INS含量最低,0.88%苏氨酸水平组血清中IL-6和IgG含量最高。5)饲粮苏氨酸水平显著影响黄羽肉鸡血液中T淋巴细胞增殖率(P0.05),黄羽肉鸡母鸡和公鸡均是0.81%苏氨酸水平组血液中T淋巴细胞增殖率最高。由以上结果可以得出,饲粮中添加适宜水平苏氨酸可以提高黄羽肉鸡生长性能、胴体品质和增强免疫功能。以生长性能为主要判定指标,确定1～21日龄黄羽肉鸡母鸡饲粮苏氨酸最适水平为0.81%,黄羽肉鸡公鸡饲粮苏氨酸最适水平为0.79%。  相似文献   

2.
22～42日龄黄羽肉鸡饲粮代谢能需求参数的研究   总被引：5，自引：0，他引：5  
为研究不同性别22～42日龄黄羽肉鸡饲粮代谢能需求参数,用1600只21日龄岭南黄鸡进行了试验。采用2(性别)×5(代谢能水平)因子试验设计,通过向玉米—豆粕型基础日粮中添加不同剂量植物油、沸石粉和玉米芯粉,配制成5种含不同代谢能水平的试验饲粮,代谢能水平分别设置为:11.715、12.134、12.552、12.970、13.389MJ/kg。试验期21天,通过观测饲粮代谢能水平对试鸡生长性能、胴体品质、空体成分、能量和粗蛋白质沉积率、肌肉脂肪含量以及部分血液生化指标的影响,确定不同性别22～42日龄黄羽肉鸡饲粮代谢能需求参数。试验结果表明:在本试验条件下,根据不同评价指标确定的22～42日龄黄羽肉鸡饲粮代谢能需求参数略有不同,雌、雄黄羽肉鸡的最适饲粮代谢能水平基本一致。以生长性能为评价指标时,雌、雄试鸡结果一致,为12.958MJ/kg;以胴体品质和能量、粗蛋白质沉积率为评价指标时,得到的结果一致,为12.122MJ/kg;根据试鸡血清胆固醇、甘油三酯和尿素氮浓度确定的结果一致,为12.540MJ/kg;以空体成分为评价指标时,得到的雌、雄试鸡最适饲粮代谢能水平分别为12.540和12.958MJ/kg;以肌肉脂肪含量为评价指标,确定雌、雄试鸡饲粮代谢能最适需要量分别为12.540和12.122MJ/kg。综合考虑本试验根据不同判据指标得到的结果,确定  相似文献   

3.
本试验旨在研究基于玉米-花生仁饼型低粗蛋白质(CP)水平饲粮对1~21日龄黄羽肉鸡生长性能和氮利用率的影响。选取1日龄快速型岭南黄羽肉鸡1920只(公母各占1/2),公、母鸡各按体重一致原则随机分为4组(每组6个重复,每个重复40只)。4个组的饲粮CP水平分别为22.5%、21.5%、20.5%和19.5%。试验期21 d。结果表明:1)饲粮不同水平CP和性别对21日龄肉鸡末重和1~21日龄平均日增重(ADG)均有显著影响(P<0.05)且具有显著交互作用(P<0.05);22.5%CP组和21.5%CP组ADG均显著高于20.5%CP组和19.5%CP组(P<0.05),饲粮CP水平对肉鸡ADG的影响具有显著线性效应(P<0.05)。22.5%CP组公鸡ADG最高,显著高于其他3个CP水平组(P<0.05),21.5%CP组公鸡ADG也显著高于20.5%CP组和19.5%CP组(P<0.05);22.5%CP组和21.5%CP组母鸡ADG均显著高于19.5%CP组(P<0.05)。2)饲粮不同水平CP对肉鸡料重比(F/G)有显著影响(P<0.05)且具有显著的线性效应(P<0.05);22.5%CP组F/G最低,显著低于其他3个水平CP组(P<0.05);21.5%CP组F/G显著低于19.5%CP组(P<0.05)。3)饲粮不同水平CP均对肉鸡氮利用率有显著影响(P<0.05)。21.5%CP组肉鸡氮利用率最高,显著高于其他3个水平CP组(P<0.05),19.5%CP组氮利用率也显著高于20.5%CP组(P<0.05)。由此可见,以玉米-花生仁饼为基础饲粮,低CP水平饲粮中尽管补充添加了晶体氨基酸,但是还是会影响公鸡生长。1~21日龄快速型岭南黄羽肉鸡母鸡饲粮CP水平可以降低1~2个百分点。建议将公、母鸡分开饲养,以实现对其营养的精准调控,提高氮利用率,降低氮排放。  相似文献   

4.
0～21和22～42日龄黄羽肉鸡可消化蛋氨酸需要量的研究   总被引：1，自引：0，他引：1  
试验一和试验二分别选用1日龄和22日龄岭南黄鸡各2 000只和1 600只,按性别和体重分成10处理组(公、母鸡各5组),每组4重复栏,每栏50(试验一)和40只鸡(试验二)。2个试验均采用5(饲粮蛋氨酸水平)×2(性别)两因子试验设计,试验一和二分别设0.35%、0.40%、0.45%、0.50%和0.55%以及0.30%、0.35%、0.40%、0.45%和0.50%5个饲粮蛋氨酸水平。结果表明:随着饲粮蛋氨酸水平提高,0～21日龄和22～42日龄公、母鸡每日总蛋氨酸摄入量和真可消化蛋氨酸摄入量呈线性或二次曲线升高(P<0.05);0～21日龄公、母鸡的日增重呈二次曲线升高(P<0.05),0～21日龄和22～42日龄公、母鸡的饲料增重比呈二次曲线降低(P<0.05或0.1)。可见,在基础饲粮中添加适量蛋氨酸改善了黄羽肉鸡的生产性能。根据二次回归模型估测黄羽肉鸡获得最佳生产性能95%处的总蛋氨酸需要量和真可消化蛋氨酸需要量,0~21日龄母鸡为0.433%~0.435%和0.404%~0.406%,公鸡为0.445%~0.454%和0.416%~0.425%,22～42日龄母鸡为0.463%和0.437%,公鸡为0.375%和0.349%。  相似文献   

5.
本试验旨在研究饲粮色氨酸对43～63日龄黄羽肉鸡生产性能、胴体品质、体成分沉积以及下丘脑5-羟色胺含量等的影响,以确定43～63日龄黄羽肉鸡色氨酸需要量.选用1 600只43日龄岭南黄鸡,采用5×2两因子设计,设5个饲粮色氨酸水平(0.11%、0.14%、0.17%、0.20%和0.23%)和公母2个性别.结果表明,基础饲粮中添加色氨酸可显著改善黄羽肉公、母鸡的生产性能,提高机体蛋白质沉积和下丘脑中5-羟色胺浓度,改善公鸡的胴体品质.不同性别黄羽肉鸡的生产性能、胴体品质和体蛋白质沉积量间存在显著差异(P<0.05).与母鸡相比,公鸡采食较多,饲料利用率和体蛋白质沉积量较高,导致其增重较快,胴体产出和腿肉产量较高.公鸡的日采食量、胸肌率和腹脂率对饲粮中色氨酸浓度变化比母鸡更敏感.根据二次回归模型估测公鸡和母鸡获得最大日增重95%处的饲粮总色氨酸含量为0.181%和0.185%(每日需要量为0.184和0.169 g/d),可消化色氨酸含量分别为0.162%和0.166%(每日需要量为0.165和0.152 g/d),色氨酸与赖氨酸比例分别为20.1∶100和20.6∶100.公、母鸡获得最大体蛋白质沉积的饲粮中总色氨酸和可消化色氨酸含量为0.17%和0.15%.  相似文献   

6.
试验旨在研究不同饲养阶段快大型黄羽肉鸡异亮氨酸需要量。分别选取0、22和43日龄快大型岭南黄鸡2400、2160和1920只,按照性别和体重随机分为8个异亮氨酸梯度水平饲粮处理,每个处理6个重复(栏),公、母各3个重复,0~21、22~42、43~63日龄3个阶段每栏分别为50、45和40只鸡。各阶段基础饲粮异亮氨酸水平分别为0.55%、0.50%和0.45%。3个阶段各处理组饲粮均在基础饲粮中呈梯度添加异亮氨酸,组间间隔水平均为0.05%,各处理饲粮除异亮氨酸外其他营养水平均一致。试验鸡地面平养,自由采食颗粒料和自由饮水。结果显示,异亮氨酸水平和性别对3个阶段鸡生长性能均有显著影响,且异亮氨酸水平和性别间存在显著互作效应(P<0.05)。随着异亮氨酸水平提高,平均日增重和料重比均呈显著或极显著二次曲线变化(P<0.05;P<0.01)。双斜率折线模型预测结果显示,0~21日龄阶段,公鸡、母鸡和公母混合鸡群的异亮氨酸需要量,以平均日增重为衡量指标分别为0.77%、0.72%和0.73%,以料重比为衡量指标分别为0.75%、0.70%和0.73%;22~42日龄阶段,公鸡、母鸡和公母混合鸡群的异亮氨酸需要量,以平均日增重为衡量指标分别为0.68%、0.64%和0.66%,以料重比为衡量指标分别为0.66%、0.62%和0.64%;43~63日龄阶段,公鸡、母鸡和公母混合鸡群的异亮氨酸需要量,以平均日增重为衡量指标分别为0.64%、0.59%和0.61%;以料重比为衡量指标分别为0.61%、0.57%和0.59%。黄羽肉鸡异亮氨酸营养需要量随日龄增加而降低,各个饲养阶段公鸡的异亮氨酸需要量均显著高于母鸡,以料重比为评定指标得到异亮氨酸营养需要量低于以平均日增重为衡量指标得的需要量推荐值。  相似文献   

7.
用1600只42日龄岭南黄鸡以2(性别)×5(代谢能水平)试验设计,向玉米-豆粕型日粮中添加不同剂量植物油、沸石粉和玉米芯粉,使5种代谢能水平分别为:12.134,12.552,12.970,13.389,13.807MJ／kg,观测鸡的生产性能。结果:以生长性能、能量和粗蛋白质沉积率以及胴体品质为评价指标时,43~63日龄最适饲粮代谢能水平分别为13.376MJ／kg、12.958MJ/kg和12.540MJ/kg;以肌肉脂肪含量为评价指标时,公、母鸡饲粮代谢能最适需要量分别为12.958和13.376MJ／kg;以空体成分为评价指标时,母鸡最适饲粮代谢能水平为12.540MJ/kg。  相似文献   

8.
正(接上期)2黄羽肉鸡氨基酸营养需要量及其平衡模式有关黄羽肉鸡氨基酸营养需要量的研究报道较少,仅8篇文献,内容多集中在蛋氨酸和赖氨酸上,评定指标主要是生长性能、胴体品质和体成分沉积。在快大型黄羽肉鸡上,适宜水平的蛋氨酸可改善黄羽肉鸡的饲料利用率和胴体品质,增加母鸡胴体和羽毛蛋白质含量或沉积量,促进羽毛生长,1~21日龄和22~42日龄阶段的日增重和料重比、43~63日龄阶段的全净膛率和胸肌率均随饲粮蛋氨酸水平呈二次曲线变化,因此,可以通过二次曲线回归方程获得最佳饲粮蛋氨酸水平  相似文献   

9.
试验旨在研究不同饲养阶段快大型黄羽肉鸡异亮氨酸需要量。分别选取0、22和43日龄快大型岭南黄鸡2 400、2 160和1 920只,按照性别和体重随机分为8个异亮氨酸梯度水平饲粮处理,每个处理6个重复（栏）,公、母各3个重复,0~21、22~42、43~63日龄3个阶段每栏分别为50、45和40只鸡。各阶段基础饲粮异亮氨酸水平分别为0.55%、0.50%和0.45%。3个阶段各处理组饲粮均在基础饲粮中呈梯度添加异亮氨酸,组间间隔水平均为0.05%,各处理饲粮除异亮氨酸外其他营养水平均一致。试验鸡地面平养,自由采食颗粒料和自由饮水。结果显示,异亮氨酸水平和性别对3个阶段鸡生长性能均有显著影响,且异亮氨酸水平和性别间存在显著互作效应（P<0.05）。随着异亮氨酸水平提高,平均日增重和料重比均呈显著或极显著二次曲线变化（P<0.05;P<0.01）。双斜率折线模型预测结果显示,0~21日龄阶段,公鸡、母鸡和公母混合鸡群的异亮氨酸需要量,以平均日增重为衡量指标分别为0.77%、0.72%和0.73%,以料重比为衡量指标分别为0.75%、0.70%和0.73%;22~42日龄阶段,公鸡、母鸡和公母混合鸡群的异亮氨酸需要量,以平均日增重为衡量指标分别为0.68%、0.64%和0.66%,以料重比为衡量指标分别为0.66%、0.62%和0.64%;43~63日龄阶段,公鸡、母鸡和公母混合鸡群的异亮氨酸需要量,以平均日增重为衡量指标分别为0.64%、0.59%和0.61%;以料重比为衡量指标分别为0.61%、0.57%和0.59%。黄羽肉鸡异亮氨酸营养需要量随日龄增加而降低,各个饲养阶段公鸡的异亮氨酸需要量均显著高于母鸡,以料重比为评定指标得到异亮氨酸营养需要量低于以平均日增重为衡量指标得的需要量推荐值。  相似文献   

10.
试验旨在研究饲粮不同硒水平对22~42日龄黄羽肉鸡生长性能、抗氧化指标的影响,从而确定快大型黄羽肉鸡饲养中期的最适硒水平。选用22日龄健康、发育良好的快大型岭南黄羽肉公雏鸡1 200只,根据体重随机分为5个组,每组6个重复,每个重复40只,试验组1(对照组)为基础日粮组(硒含量0.037 mg/kg),试验组2、3、4、5饲粮则在基础日粮中分别添加0.075、0.15、0.225、0.30 mg/kg硒,试验期为21 d。结果表明:饲粮添加不同水平硒对试验鸡生长性能无显著影响(P0.05);各硒添加组血浆、红细胞和肝脏谷胱甘肽过氧化物酶(GSH-Px)活力显著高于对照组(P0.05),饲粮添加不同水平硒对试验鸡血浆和肝脏丙二醛(MDA)含量无显著影响(P0.05)。综合考虑,22~42日龄黄羽肉鸡饲粮硒适宜水平为0.337 mg/kg。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

14.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

15.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

16.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

17.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

18.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

19.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

20.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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