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91.
甘南玛曲不同年龄欧拉型藏羊放牧采食量季节动态研究   总被引:1,自引:0,他引:1  
为确立高寒地区天然草地欧拉型藏羊放牧采食量的季节动态变化,本试验采用TiO2外源指示剂法和瘤胃尼龙袋法分别测定欧拉型藏羊不同季节排粪量和牧草消化率从而计算放牧采食量。结果表明:玛曲高寒草地牧草干物质消化率(DMD)和粗蛋白(CP)含量夏季显著(P < 0.05)高于冬春季与秋季;欧拉型藏羊各年龄段排粪量3季差异显著(P < 0.05)且秋季 > 夏季 > 冬春季;随着年龄增长,欧拉型藏羊三季牧草采食量均有增大的趋势,同年龄段不同季节的藏羊采食量和代谢采食量(除4岁母羊)差异显著(P < 0.05)且秋季 > 夏季 > 冬春季;各年龄段藏羊累计牧草消耗量(AFC)差异显著(P < 0.05)分别为339.37,757.58,1185.93和1655.61 kg。由此可见,牧草干机物质消化率、排粪量和采食量夏秋季较高、冬春季较低,随着年龄增大排粪量和采食量有增高的趋势。因此,在高寒牧区应提倡草地季节性畜牧业,充分考虑牧草营养与动物营养需求之间的耦合性来提高经济和生态效益。  相似文献   
92.
Epizootics of sudden death in tammar wallabies (Macropus eugenii) occurred at six research facilities and zoological gardens in New South Wales, Australia, in late 1998 and at one Queensland research facility in March 1999. There were 120 confirmed tammar wallaby deaths during this period; however, population censuses indicated that up to 230 tammar wallabies may have died. The majority of animals died without premonitory signs. A small proportion of wallabies exhibited increased respiratory rate, sat with a lowered head shortly before death or were discovered in lateral recumbency, moribund and with muscle fasciculations. Gross postmortem findings consistently included massive pulmonary congestion, mottled hepatic parenchyma and subcutaneous oedema throughout the hindlimbs and inguinal region. Approximately 30% of the animals examined also had extensive haemorrhage within the fascial planes and skeletal muscle of the hindlimb adductors, inguinal region, ventral thorax, dorsal cervical region and perirenal retroperitoneal area. The tissues of affected animals became autolytic within a short period after death. Bacteriological examination of tissues from 14 animals did not provide any significant findings. Toxicological examination of the gastric and colonic contents of four animals did not reveal evidence of brodifacoume or other rodenticides. Viruses from the Eubenangee serogroup of the Orbivirus genus were isolated from the cerebral cortex of nine, and the myocardium of two, tammar wallabies and the liver and intestine of another tammar wallaby. A similar orbivirus was also isolated from the cerebrospinal fluid of another tammar wallaby that died suddenly. The disease agent appears to be a previously unrecognised orbivirus in the Eubenangee serogroup. This is the first report of epizootics of sudden deaths in tammar wallabies apparently associated with an orbivirus infection.  相似文献   
93.
为建立特异性和敏感性高的检验犬细粒棘球绦虫感染的方法。用细粒棘球绦虫(简称,Eg)成虫抗原分别免疫兔和绵羊,收集高免血清,纯化的高免抗体。依据抗体夹心ELISA工作原理,以兔抗体包被,检测感染Eg、不同犬带科绦虫的实验犬和空白犬粪样,绵羊抗体扑捉抗原,HRP标记兔抗绵羊IgG(1∶8 000)催化显色,用酶标仪测定OD 405nm吸光度,用以确定其特异性和敏感性。试验结果表明,敏感性为82.69%(43/52),特异性为85.88%(140/163);粪抗原在感染细粒棘球绦虫16d后可检出,最低抗原浓度为9.7ng/mL即犬感染5条成虫时可检测出阳性。该检测方法具有较好的特异性和灵敏性,为进一步研制检测细粒棘球绦虫虫体抗原ELISA检测试剂盒奠定了基础。  相似文献   
94.
The relationship between serum minerals and stress and(or) disease has not been fully evaluated in beef cattle. Two trials were conducted to determine the changes in serum Cu and Zn during market-transit stress and(or) disease. Two additional trials were conducted to determine the changes in serum Cu and Zn after inoculation with infectious bovine rhinotracheitis virus (IBRV), with one of the trials determining the changes in serum Ca and P. Trials 1 (n = 80) and 2 (n = 100) utilized calves that were handled through a normal market-transit system and transported 1,967 km to the feedlot. Trials 3 (n = 37) and 4 (n = 8) used calves that were sero-negative to IBRV and then challenged with 2.7 x 10(5) plaque-forming units of the virus. Serum samples were collected at specified intervals and serum minerals were measured for each trial. Serum Zn for morbid or IBRV-challenged calves was decreased by 34, 57, 29 and 15% (P less than .05) for the four trials, respectively, at peak morbidity. Serum Cu of morbid or IBRV-challenged calves increased 5, 15, 40 and 33% for the four trials, respectively, at peak morbidity. Feed intakes were lower during morbidity for market-transit trials and after IBRV inoculation. Lower feed intake could partially explain the decrease in serum Zn; however, when feed intake was held constant, serum Zn concentration still decreased. Serum Zn decreased and serum Cu increased during market-transit morbidity or after IBRV.  相似文献   
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97.
Groups of Hereford weaners carrying naturally acquired infestations of L. vituli were allocated to a factorial experiment to examine the effect of lice treatment, sex and nutrition on growth rate during winter and early spring. Plane of nutrition was the only factor influencing growth rate over this period. In untreated groups of cattle, the plane of nutrition influenced the lice score but lice score did not influence growth rate.  相似文献   
98.
Glutathione transferases in soybean (GmGSTs) involved in herbicide detoxification in cell suspension cultures were purified by S-hexylglutathione affinity chromatography and resolved by a combination of HPLC and SDS-PAGE into 11 polypeptides. Analysis by Western blotting using antisera raised to three previously characterised tau (GmGSTU) class subunits demonstrated that five polypeptides were related to GmGSTU1, three to GmGSTU2, and one to Gm GSTU3. Plants contained a simpler profile of polypeptides, with a single GmGSTU2-like polypeptide predominating. With respect to herbicide detoxification, two GmGSTU2-related polypeptides dominated the activity toward the chloroacetanilide acetochlor, while an unclassified subunit was uniquely associated with the detoxification of diphenyl ethers (acifluorfen, fomesafen). The inducibility of the different GST subunits was determined in soybean plants exposed to photobleaching diphenyl ethers and the safeners naphthalic anhydride and dichlormid. GmGSTU3, a GmGSTU1-like polypeptide, and thiol (homoglutathione) content were induced by all chemical treatments, while two uncharacterised subunits were only induced in plants showing photobleaching.  相似文献   
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100.
This case report describes the accidental intramuscular administration of 20 mL Gudair® vaccine to a 7‐year‐old Standardbred mare and successful treatment of the resulting inflammatory reaction by radical surgical resection.  相似文献   
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