绵羊铅镉联合中毒的研究

研究了白银矿区周围绵羊以消瘦和贫血为主要特征的疾病。通过检测食物链系统及绵羊全血、被毛和组织器官中１３种矿物元素（Ｐｂ、Ｃｄ、Ｚｎ、Ｆｅ、Ｍｎ、Ｍｏ、Ｃｕ、Ｆ、Ａｓ、Ｓｅ、Ａｌ、Ｃａ、Ｐ）的含量，分析血液生理生化指标的变化，揭示出现地牧草中Ｐｂ、Ｃｄ的含量高，分别为（１１１．２±９８．４）μｇ／ｇ和（１２．０±１．２）μｇ／ｇ；动物体内的Ｐｂ、Ｃｄ沉积量亦极显著高于允许值（Ｐ＜０．０１）；动物呈低色素小细胞性贫血，血清ＬＤＨ、ＡＬＴ活性和Ｔ３含量显著升高（Ｐ＜０．０１），血清蛋白含量降低（Ｐ＜０．０１），以及实质器官变性、坏死，肾小管上皮细胞核包涵体等病理学特点。确认该病系工业环境污染所致的绵羊铅镉联合中毒     

实验性皮肤角化不全症仔猪被毛及各组织中锌、铜含量测定

以钙：锌＝３３０：１与５１６：１的日粮饲喂健康断乳仔猪１２０天，复制了仔猪皮肤角化不全症。患病仔猪被毛中锌、铜含量呈逐渐下降趋势，锌含量极显著低于正常组（Ｐ＜０．０１），而铜含量则与正常组差异不显著（Ｐ＞０．０５）。患病仔猪肝、十二指肠、肠系脱淋巴结中锌含量极显著低于正常组（Ｐ＜０．０１），心、肾、脑中锌含量著低于正常组（Ｐ＜０．０５），脾、肺、左侧最后肋骨、背最长肌、胰中锌含量与正常组差异不显著（Ｐ＞０．０５），肝、背最长肌中铜含量极显著高于正常组（Ｐ＜０．０１），脾中铜含量显著高于正常用（ｐ＜０．０５），脑、心中铜含量极显著低于正常组（Ｐ＜０．０１），肾中铜含量显著低于正常用（Ｐ＜０．０５），其余组织中铜含量与正常组差异不显著（Ｐ＞０．０５）。本试验测定了正常仔猪和用化不全症仔猪各组织中锌、铜的含量，报告了角化不全症仔猪心、肺、肠系膜淋巴结中锌、钢含量及被毛中锌、钢含量的动态变化。     

双峰驼骨质疏松症的临床化学研究

用放射免疫技术和临床化学方法研究了骨质疏松症双峰驼血清甲状旁腺激素（ＰＴＨ）、三碘甲腺原氨酸（Ｔ３）、甲状腺素（Ｔ４）的含量和一系列血液临床化学指标的变化。结果表明,病驼血清ＰＴＨ、Ｔ３和Ｔ４含量分别为１４６７±６０８ｎｇ／Ｌ、２３２±１１３ｎｍｏｌ／Ｌ和７２６±２７９ｎｍｏｌ／Ｌ,与健康驼相比极显著升高（Ｐ＜００１）,血清无机磷（ＩＰ）含量极显著降低（Ｐ＜００１）,血清碱性磷酸酶（ＡＬＰ）活性极显著升高（Ｐ＜００１）,并同时伴有血清乳酸脱氢酶（ＬＤＨ）活性、肌酐、α球蛋白和β球蛋白含量明显升高（Ｐ＜００１或Ｐ＜００５）。提示钙磷代谢紊乱所致ＰＴＨ分泌的增加可能是骨质疏松症发生的关键,对其发生机理进行了探讨。     

低磷奶牛血红蛋白尿症红细胞膜脂质过氧化损伤的观察

研究观察了土壤、牧草低磷条件下,诱发奶牛红细胞膜脂质过氧化损伤。发现血清磷、红细胞膜总脂和过氧化物歧化酶（ＳＯＤ）明显下降：血清磷由（４３．１０±８．１０３）ｍｇ／ｇ下降至（２１．３３±２．２３１）ｍｇ／ｇ;膜总脂由（０．００２６７±０．０００１２９）ｇ／ｍＬ下降至（０．００２２４±０．０００１２９）ｇ／ｍＬ;ＳＯＤ由（２１７．６５±３．０４１）Ｕ／ｍＬ下降至（４０．６２±５．４４）Ｕ／ｍＬ,差异显著（Ｐ＜０．０１）。但微粘度（η）和红细胞丙二醛（ＭＤＡ）上升：η值由０．８４３３±０．０２１５上升至１．７２８５±０．１４５１,表明膜流动性下降;ＭＤＡ由（０．５３６±０．０７８）ｎｍｏｌ／ｍＬ上升至（１．０９３±０．１８０）ｎｍｏｌ／ｍＬ,差异显著（Ｐ＜０．０１）。结果显示,低磷不仅引起奶牛血红蛋白尿症而且诱导红细胞膜脂质过氧化损伤。     

家兔初乳溶菌酶含量测定

采用琼脂平板法测定家兔初乳溶菌酶含量。结果表明，初乳溶菌酶含量为（７．９６±２．０１） μｇ／ｍ Ｌ，常乳溶菌酶含量（５．０１±１．３２）μｇ／ｍ Ｌ，两者比较差异极显著（Ｐ＜０．０１）。     

不同水平微量元素锰,铜,锌对亚康小公雏增重的影响

选择健康亚康小公雏１０８羽,随机分成３组,每组３６羽。以基础日粮中锰、铜、锌含量为对照组,以每千克饲料添加锰０．８ｇ、铜０．４ｇ、锌０．１ｇ为试验１组;以每千克饲料添加锰４ｇ、铜２ｇ、锌３ｇ为试验２组,经３０ｄ试验结果表明,试验１组的增重效果极显著高于对照组（Ｐ＜０．０１）,显著高于试验２组（Ｐ＜０．０５）;试验２组与对照组差异显著（Ｐ＜０．０５）。胫骨中钙磷含量和血清中锰、铜、锌的含量３个组间差异均不显著（Ｐ＜０．０５）。但随着铜、锰、锌在日粮中的含量增加,胫骨中钙含量有降低的趋势,磷不受其影响。     

鲁西黄牛发情周期和产后期外周血浆孕酮水平

在鲁西黄牛母牛的发情周期和产后期（产犊至产后６０ｄ）收集颈静脉血样，用放射免疫分析法测定血浆孕酮（Ｐ４）水平。结果表明，母牛的发情周期平均为（２１．２±１．６）ｄ，发情当天（０ｄ）外周血浆孕酮水平为（０．５２±１．４）μｇ／Ｌ，在周期的９～１５ｄ，孕酮水平较高，其峰值为（４．６２±１．５６）μｇ／Ｌ（ｎ＝１５），在周期的约１８ｄ以后，孕酮水平迅速下降，至周期的２１ｄ降至发情开始时的水平；母牛产后１０．６～１３．６ｄ以后，外周血浆孕酮水平开始升高，出现黄体周期，约有一半的母牛产后第１个黄体周期为（８．４±０．５）ｄ，显著短于正常周期（２０．１±３．２）ｄ（Ｐ＜０．０１）；在短周期中，孕酮峰值为（１．５２±０．７１）μｇ／Ｌ，亦显著低于正常周期孕酮峰值（３．８４±１．２５）μｇ／Ｌ（Ｐ＜０．０５）。除短周期外，产后发情周期中的孕酮水平变化与通常的发情周期基本相同     

17β─雌二醇主动免疫对公兔生殖的影响

以１７β－雌二醇－６－人血清白蛋白对新西兰公兔进行主动免疫，用ＲＩＡ检测抗体滴度和１７β－雌二醇及睾酮浓度，并检测睾丸重量和间质细胞面积。结果，试验组各兔均不同程度地产生了１７β－雌二醇抗体，其血浆１７β－雌二醇浓度极显著地低于对照组〔（２０．３±２１．６）ｎｇ／Ｌ，（１６７．７±４９．６）ｎｇ／Ｌ，Ｐ＜０．００１〕，睾酮浓度极显著地高于对照组〔（７．３±７．１）μｇ／Ｌ，（０．５２±０．２９）μｇ／Ｌ，Ｐ＜０．０１〕。每侧睾丸重量和间质细胞面积均极显著地大于对照组〔（３．９４±０．９３）ｇ和（２５２．２５±８５．７８）μｍ２，（２．９８±０．７２）ｇ和（１６１．７９±３６．４５）μｍ２，Ｐ＜０．０１和Ｐ＜０．００１〕。提示１７β－雌二醇主动免疫可望成为提高雄性动物生育力的有效途径之一     

山鸡肉用性能的比较及营养价值分析

对不同性别的美国山鸡进行产肉性能的测定表明，雄山鸡屠宰性能极显著高于雌山鸡，经ｔ检验，屠宰率、半净膛率、全净膛率雌雄间差异极显著（Ｐ＜０．０１）；而雌山鸡的分割率极显著高于雄山鸡，经ｔ检验，胸肌率、翅膀率、腿比率、腿肌率雌雄间差异极显著（Ｐ＜０．０１）。用同法对山鸡和艾维茵肉仔鸡作比较，其屠宰率差异不显著（Ｐ＞０，０５），而半净膛率、全净膛率山鸡明显高于艾维茵肉仔鸡，差异极显著（Ｐ＜０．０１），翅膀率、腿比率、胸肌率山鸡明显小于肉仔鸡，差异极显著（Ｐ＜０．０１）。用同法将山鸡与鹧鸪相比较，其屠宰率、胸肌率、翅膀率差异不显著（Ｐ＞０．０５），山鸡半净膛率、全净膛率明显高于鹧鸪，差异极显著（Ｐ＜０．０１），而腿比率、腿肌率，山鸡明显小于鹧鸪，差异极显著（Ｐ＜０．０１）。对山鸡（２雄，６雌）进行营养含量的分析，结果表明，山鸡鲜肉氨基酸总含量，雄性为２３．１４ｇ／１００ｇ，雌性为２４．７３ｇ／１００ｇ，前者显著低于后者（Ｐ＜０．０５）；而山鸡与家鸡比较，山鸡氨基酸总含量均极显著高于家鸡（家鸡为１６～１８ｇ／１００ｇ），矿物质的测定结果表明，山鸡鲜肉和肝脏均含有丰富的铜、铁、锌、锰及钙和磷等元素，尤以铁的含量特别高，?     

克伦特罗在猪体内的生物利用度及药物动力学研究

６头体重４７．００±４．５７ｋｇ（Ｘ±Ｓ）的健康长白和大白杂交猪，拉丁方设计试验，按４ｍｇ／ｋｇ静注、肌注和内服克伦特罗，高效液相色谱法检测血浆中药物浓度，ＭＣＰＫＰ药代动力学程序处理药时数据。静注给药的药代动力学参数是：ｔ１／２α０．６２±０．１２ｈ，ｔ１／２β４．８７±１．５６ｈ，Ｖｄ（ａｒｅａ）４．４８±０．５６ｌ／ｋｇ，ＣｌＢ０．６３±０．１１ｌ／ｋｇ／ｈ，ＡＵＣ６．３９±１．２７μｇ／ｍｌ．ｈ。肌注给药的药动学参数是：ｔ１／２Ｋａ０．２２±０．１０ｈ，ｔ１／２α０．５６±０．２１ｈ，ｔ１／２β４．２５±１．１０ｈ，ｔｍａｘ０．６０±０．１３ｈ，Ｃｍａｘ１．２７±０．３５μｇ／ｍｌ，ＡＵＣ５．４８±１．２９μｇ／ｍｌ．ｈ，Ｆ８５．４０±４．６９％。内服给药的药动学参数是：ｔ１／２Ｋａ０．２８±０．１５ｈ，ｔ１／２Ｋｅ３．１５±０．３６ｈ，ｔｍａｘ１．４６±０．１９ｈ，Ｃｍａｘ０．６５±０．１３μｇ／ｍｌ，ＡＵＣ３．９３±０．９９ｍｇ／ｌ．ｈ，Ｆ６１．０２±１０．９０％。肌注给药的生物利用度与内服比较，差异极显著（Ｐ＜０．０１）。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

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.     

Prevalence of gastric lesions in racing Alaskan sled dogs

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.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

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.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

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.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein