兽用鸡脾转移因子的多肽组成研究

为了研究兽用鸡脾转移因子的多肽组成,利用冻融一透析法制备兽用鸡脾转移因子溶液,分别采用福林酚法测定多肽含量,基质辅助激光解析电离飞行时间质谱法（MALDI—TOF-MS）测定分子量,液相色谱-质谱联用法（LC—MS）分析多肽组成,脱E受体法测定转移因子活力。鸡脾转移因子溶液多肽含量为1570．8μg／mL．活力为10．92％,LC—MS法测得多肽分子量为800～7476Da,多肽种类581种,包括T细胞凋亡抑制相关蛋白（TIALl）等多种生物活性蛋白。初步揭示了兽用鸡脾转移因子的多肽组成。有助于进一步研究其有效成分和作用机理。     

奶牛特异性转移因子的制备及其免疫活性检测

通过冷冻透析法制备奶牛隐性乳房炎特异性转移因子,并对其免疫活性进行检测。方法为采用匀浆、冻融、透析被免疫猪的脾脏,制备特异性转移因子,运用理化性质检验、安全试验、无菌试验检验所制备转移因子的纯度及安全性,并运用小鼠巨噬细胞吞噬功能试验及E玫瑰花环试验对特异性转移因子免疫活性进行检测。试验结果为:所制备的奶牛隐性乳房炎特异性转移因子多肽含量为1.3 p g/mL,核酸含量为24μg/mL,OD_(260 nm)/OD_(280 nm)值为2.08,且安全、无菌。巨噬细胞吞噬功能试验及E玫瑰花环形成试验表明转移因子可明显增加巨噬细胞吞噬能力并能增加E玫瑰花环的形成数。因此,本品可作为奶牛隐性乳房炎的治疗药物,亦可作为细胞免疫增强剂使用。     

鸡转移因子的制备及其应用研究──Ⅰ．制备及理化、生物特性检测

以肉鸡脾脏为原科，经加工提取鸡转移因子，经过对粗制及纯化的鸡转移因子的理化特性及生物学特性的检验．证明的转移因子与其它动物的转移因子相近；多肽含量及组分不及哺乳类动物。     

两种奶牛功能性添加剂效果对比试验

选取泌乳期高产和低产奶牛各18头。高产和低产中各随机选取9头在日粮中添加纤维素复合酶,添加量为0．1kg／t精料;其余18头在日粮中添加酵母培养物,添加量为2kg／t精料。结果显示,高产组饲喂纤维素复合酶的奶牛试验期第35天时产奶量显著高于饲喂酵母培养物的奶牛（P=0．024）,低产组饲喂纤维素复合酶的奶牛试验期内产奶量呈稳步上升趋势;高产组饲喂纤维素复合酶的奶牛乳脂率在试验期28天显著高于同组中饲喂酵母培养物的奶牛（P=0．022）,乳蛋白率在试验第7天（P=0．044）和第28天（P=0．018）显著高于同组中饲喂酵母培养物的奶牛。     

鸭脾脏转移因子的提取与活性鉴定

以肉鸭加工过程中的废弃物——脾脏为原料,用pH值调节——超滤法提取鸭脾脏转移因子,过滤除茵后制成脾脏转移因子溶液,对提取工艺和鉴定方法进行优化改进,显著提高产品收率及质量标准,对其进行理化性质、生物活性、有效成分及安全性检测鉴定,表明：本研究提纯的鸭脾脏转移因子不舍有蛋白质,主要成分为多肽,含有核苷酸、核糖成分,无菌试验、热原试验、过敏试验及安全试验结果均符合生物制剂的质量标准,该研究对鸭脾脏转移因子的开发利用提供了试验依据。     

新必妥对仔猪体液免疫效果的影响

本试验选取21日龄的健康仔猪12头，随机分为3组，分别肌肉注射猪瘟兔化弱毒疫苗1头份（对照组）、猪瘟兔化弱毒疫苗1头份＋猪脾转移因子0．15mL／kg体重（试验1组）和猪瘟兔化弱毒疫苗1头份＋猪脾转移因子0．25mL／kg体重（试验2组），分别于21、60日龄各免疫1次．以研究猪脾转移因子对仔猪猪瘟兔化弱毒疫苗免疫效果的影响。结果表明．首免后14～35d试验组的免疫效果均显著优于对照组，二免后5～15d试验2组显著优于对照组。另外，选取35日龄的健康仔猪12头，随机分为3组，分别肌肉注射猪蓝耳病弱毒疫苗1头份（对照组）、猪蓝耳病弱毒疫苗1头份＋猪脾转移因子0．15mL／kg体重（试验1组）和猪蓝耳病弱毒疫苗1头份＋猪脾转移因子0．25mL／kg体重（试验2组），以研究猪脾转移因子对仔猪蓝耳病弱毒疫苗免疫效果的影响。结果表明，免疫后14～35d试验组的免疫效果均显著优于对照组，42～60d试验2组显著优于对照组。表明猪脾转移因子对仔猪体液免疫有一定的增强作用。     

鸡转移因子的制备及其应用研究：Ⅰ.制备及理化,生物特性检测

以肉鸡脾脏为原料，经加工提取鸡转因子。经过对粗制及吨化的鸡转移因子的理化特性及生物学特性的检验，证明鸡的转移因子与其它动物的转移因子相近；多肽含量及组分不及哺乳类动物。     

非特异性转移因子对犬淋巴细胞转化增殖的影响

转移因子(TF)是白细胞中有免疫活性的T淋巴细胞释放的一类低分子肽与核苷酸复合物,具有分子质量小、无热源、无免疫原性、无毒副作用、不引起过敏反应、不产生对抗抗体且可超越种系界限应用等优点.可利用动物的脾脏、淋巴细胞或外周血白细胞透析液制备转移因子,具有来源广、容易获取的特点.试验首次采用淋巴细胞体外培养技术制备非特异性转移因子,不但降低了生产成本,为产业化的原料来源提供了有力保证,也避免了传染病的水平传播.同时,通过研究非特异性转移因子对犬淋巴细胞转化、增殖的影响为犬病毒病的防治提供了有效的方法及可靠的依据.     

纤维素复合酶对奶牛消化率影响的效果分析

纤维素复合酶饲喂奶牛实验表明,在日粮中添加1％的纤维素复合酶可使奶牛消化率中的干物质（DM）下降0．47％、粗蛋白质（CP）下降2．27％、中性洗涤纤维（NDF）下降6．07％、酸性洗涤纤维（ADF）下降1．34％。结果表明：纤维素复合酶作为奶牛的饲料添加剂可明显提高奶牛的消化率。     

牛转移因子在兽医临床中的应用

转移因子（TF）是淋巴因子的一种，为非蛋白，分子量小于5000，没有抗原性，是一种低分子的多核苷酸或核苷酸-肽复合物。主要在于动物的淋巴结和脾脏的淋巴结细胞内。主要功能是使受体未致敏的淋巴细胞转化为具有免疫活性的淋巴细胞，从而增强受体免疫力而达到治疗作用。人工提纯转移因子一般选用健康动物脾脏，纯捣碎后超滤而获得。转移因子在兽医临床上主要用于细菌性和病毒性传染病的治疗与辅疗，效果显著。     

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