鸽新城疫疫苗的安全性及免疫效果观察

对我们所研制的鸽新城疫油佐剂灭活苗进行一系列安全性及免疫效果的观察,结果表明,疫苗对健康肉鸽和赛鸽都很安全;每鸽肌肉注射0.5毫升疫苗后,12天能耐受强毒的攻击;疫苗免疫期在6个月以上;疫苗4℃保存6个月以上仍有免疫效果。经对17314羽肉鸽和赛鸽进行了扩大试验,也证明疫苗十分安全有效。     

鸽Ⅱ型副粘病毒病蜂胶疫苗免疫原性研究

针对鸽Ⅰ型副粘病毒病在我国的流行情况研制了蜂胶佐剂疫苗,并对该疫苗免疫原性进行了研究,结果表明蜂胶疫苗对鸽十分安全,每鸽最佳肌肉注射剂量为0.5 m l,7 d后便能抵抗强毒攻击,免疫保护期在6个月以上,疫苗在室温或4℃条件下保存12个月仍具有良好的免疫原性。     

鸽Ⅰ型副粘病毒病蜂胶疫苗免疫原性研究

针对鸽Ⅰ型副粘病毒病在我国的流行情况研制了蜂胶佐剂疫苗,并对该疫苗免疫原性进行了研究,结果表明蜂胶疫苗对鸽十分安全,每鸽最佳肌肉注射剂量为0.5 ml,7 d后便能抵抗强毒攻击,免疫保护期在6个月以上,疫苗在室温或4℃条件下保存12个月仍具有良好的免疫原性.     

禽痘接种无局部反应说明接种无效

用于预防鸡痘的疫苗有两类，一类是由鸽痘毒制成，另一类由鸡痘弱毒病毒制成。鸽痘原的鸡痘蛋白筋胶弱毒疫苗毒力较适用于各种日龄的鸡免疫，即使对１日龄雏鸡进行免疫，也不会引起反应，但免疫力较差。鸽痘原疫苗也是未减弱的自然毒株，所以对鸽有时会引起严重反应。鸡痘原的鹌鸽化、鸡胚或鸭胚化的弱毒疫苗，毒力较鸽痘原的强，适用于２０日龄以上的鸡，用于幼鸡，有时可能会引起轻微的反应，可以在１４日龄以后接种，此苗一般囊种见以周苗是免疫期为５个月以上。以上疫苗经接种后或羽囊涂擦后，于接种部位均可出现反应，如羽毛囊涂擦鸡痘…     

鸽新城疫灭活疫苗的研制及免疫效果研究

利用近年来分离到的鸽Ⅰ型副黏病毒ND32株进行鸽新城疫油乳剂灭活疫苗的研制,并对制备疫苗的性状、安全性、免疫效力等进行检验,结果表明制备疫苗的各项指标均符合生物制品通则的要求,对疫苗的最小免疫剂量、抗体产生及免疫持续期、与同类产品的交叉攻毒保护对比效果进行了进一步试验,结果表明疫苗的最小免疫剂量为0.15 mL/只,疫苗以0.3 mL/只免疫剂量进行一次免疫,免疫持续期为3个月,以0.3 mL/只免疫剂量进行二次免疫,免疫持续期可达6个月.交叉攻毒保护对比试验结果表明所制备的鸽新城疫灭活疫苗对鸽Ⅰ型副黏病毒ND32株和鸡新城疫病毒北京株(CVCC AV1611)的攻毒保护效果均优于鸡新城疫(La Sota株)灭活疫苗.     

鸡新城疫疫苗对鸽副黏病毒病免疫效果观察

近年来,鸽副黏病毒病在我国多个省市均有流行的报道,由于国内尚无专用的鸽副黏病毒病的市售疫苗,大多养鸽场采用鸡新城疫Ⅳ系活疫苗每1个月或2个月饮水1次的免疫方法,但免疫效果不够理想,有的鸽场仍有本病流行,并造成了较大的经济损失.为了探索鸡新城疫疫苗对鸽副黏病毒病的免疫效果,制定科学的免疫程序,本试验根据相关文献[1,2]报道,用鸡新城疫Lasota株（Ⅳ系）活疫苗、鸡新城疫CS2株（I系）活疫苗设计了两种免疫方法,选择曾有副黏病毒病流行的某规模肉鸽场进行了现场试验,收到了满意的效果,并在该场进行了扩大试验,使鸽副黏病毒病的流行得到了有效控制.现报告如下.     

鸡产蛋减少综合症(EDS-76)油乳剂灭活苗的安全性及免疫效果观察

对鸡产蛋减少综合症油乳剂灭活苗进行了一系列安全性及免疫效果的观察.结果表明,疫苗对健康鸡很安全,每只鸡肌肉注射0.5 mL疫苗后,9 d产生免疫保护力,疫苗免疫期在12个月以上.疫苗4～8℃保存12个月以上,11～20℃保存3个月仍有免疫效果.此疫苗在甘肃省推广试用80万只份,安全可靠,免疫持续期长,能有效地预防和控制EDS-76的发生和流行.     

鸽禽Ⅰ型副粘病毒病蜂胶佐剂灭活疫苗的研制

鸽禽Ⅰ型副粘病毒（A/PMV-Ⅰ）病是鸽的一种严重病毒性传染病，给养鸽业造成了巨大损失。为了更好地预防本冱的发生，我们用从现场分离鉴定的7株鸽A/PMV-Ⅰ毒株中筛选出3株抗原性良好的毒株作为种毒，研制成蜂胶佐剂混合毒株灭活疫苗，经安全试验、最佳免疫剂量测定、铲力试验，以及田间应用的结果，表明该疫苗抗原性良好、使用安全和免疫保护效果确定。实验室试验，用本疫苗免疫后30、90、180天，其保护脂数分别为100%、77.8%和55.6%,免疫有效期最少达6个月；在4℃-8℃保存,其有效其最少可达180天。     

鸽新城疫rGX-mF株灭活疫苗的制备及免疫原性分析

为有效控制临床中鸽新城疫的发生，选取基因Ⅵ型鸽新城疫病毒弱毒株rGX-mF作为疫苗候选株，评价其生物学特性，并将rGX-mF灭活后制备成油佐剂灭活疫苗，接种雏鸽和SPF鸡进行rGX-mF株的免疫原性分析，为研制安全高效的鸽新城疫灭活疫苗奠定基础。结果表明，rGX-mF株能够在鸡胚中稳定传代，效价高，毒力弱；rGX-mF株灭活疫苗接种雏鸽后疫苗吸收良好，无局部和全身不良反应，安全性好，免疫持续期长达12个月；rGX-mF株灭活疫苗与LaSota株灭活疫苗相比，rGX-mF株灭活疫苗在鸽体内能产生更高水平的抗体；rGX-mF株灭活疫苗同时免疫SPF鸡和雏鸽，SPF鸡产生的抗体显著高于鸽产生的抗体，这可能与鸽和鸡的免疫系统存在差异有关。综上，利用基因Ⅵ型鸽新城疫病毒弱毒rGX-mF株制备的灭活疫苗可在鸽体内产生有效的抗体，免疫效果好，免疫持续期长。     

鸽痘疫苗的研究

本研究采用鸡胚连续传代的方法,使自然鸽痘强毒致弱,从而获得一株免疫原性好、安全且使用简便的鸽痘弱毒疫苗株。结果表明弱毒株所制疫苗接种鸽体后10～14天,便产生最少达9个月的坚强免疫力,现场试验的保护指数在88以上,使用于出壳当天的雏鸽也未见有任何不良的接种反应。置零下28～30℃冰箱中疫苗及其种毒分别经12、24个月效果均未受影响。     

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.     

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.     

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.     

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