鸡新城疫、传染性支气管炎病毒同胚接种试验

通过对五个批次的无特定病原体(SPF)鸡胚进行鸡新城疫病毒（NDV）、鸡传染性支气管炎病毒（IBV）同胚接种,收获72～120 h死胚及120 h活胚尿囊液,分别测定NDV和IBV的病毒含量,结果表明NDV病毒含量达到了108.3～108.7EID50/0.1mL, IBV的病毒含量达到了106.3～106.5EID50/0.1mL。两种病毒含量均达到《中华人民共和国兽用生物制品制造及检验规程》（2000版）中鸡新城疫、传染性支气管炎二联活疫苗病毒含量要求的标准。表明该方法即可降低成本,又简化了生产工艺。     

新城疫传染性支气管炎病毒单胚同胚接种试验的比较

通过对五个批次的无特定病原体(SPF)鸡胚进行鸡新城疫病毒(NDV)、鸡传染性支气管炎病毒(IBV)同胚接种,收获72～120 h死胚及120 h活胚尿囊液,分别测定NDV和IBV的病毒含量,结果NDV病毒含量达到了108.3～108.7 EID50/0.1mL, IBV的病毒含量达到了106.3～106.5 EID50/0.1mL.两种病毒含量均达到<中华人民共和国兽用生物制品规程>(2000年版)中鸡新城疫、传染性支气管炎二联活疫苗病毒含量要求的标准.表明该方法即可降低成本,又简化了生产工艺.     

同胚增殖鸡新城疫-传染性支气管炎病毒效果的研究

本试验将鸡新城疫病毒LaSota株、传染性支气管炎病毒M41强毒株按不同倍数稀释后,同胚接种10日龄易感鸡胚,接种后72、96 h分别收获病毒液,通过鸡胚半数感染量(EID50)测定病毒含量。结果表明:72、96 h收获的病毒液病毒含量差异不明显,均能达到配苗要求,但72h病毒液收量最多。本试验为生产高质量鸡新城疫-传染性支气管炎二联灭活疫苗、降低成本提供了一定参考。     

鸡传染性支气管炎和鸡新城疫混合感染的诊断

某养鸡场28~43日龄的肉鸡临床出现呼吸道症状,通过鸡胚接种、血凝及血凝抑制试验,进行实验室病毒分离鉴定,本病确诊为鸡传染性支气管炎(IB)和鸡新城疫(ND)混合感染。对混有IB病毒和ND病毒的鸡胚尿囊液进行酸处理,去除ND病毒,获得纯IB病毒。分离的传染性支气管炎毒株,体外和体内试验表明该传染性支气管炎病毒株对鸡新城疫病分离毒株的血凝性有强的干扰作用,对鸡新城疫的疫苗Lasota株干扰作用不明显。     

中和温度对鸡新城疫、鸡传染性支气管炎二联活疫苗中鸡传染性支气管炎病毒含量影响的研究

采用分别测定每羽份疫苗成品和每0．1mL半成品胚液鸡胚半数感染量(EID50)的方法探讨了中和温度对鸡新城疫、鸡传染性支气管炎二联活疫苗中鸡传染性支气管炎病毒含量的影响。结果显示，中和温度对该二联活疫苗中鸡传染性支气管炎病毒的EID50有显著的影响。测定病毒含量时，中和条件以中和温度控制在20℃、中和时间45～60min较为合适。     

鸡新城疫与鸡传染性支气管炎弱毒主同一鸡胚内共培养制备二联苗的研究

鸡新城疫与传染性支气管炎都是严重影响养禽业的呼吸道传染病，使用疫苗可有效地防止这两种禽病的发生。使用鸡新城疫与传染性支气管炎二联苗，其效力与单苗基本相同，具有使用简便、接种程序简单等优点，这类多联苗的发展已为一种趋势。通常制备鸡新城疫与传染性支气管炎疫苗的程序是先分别制备这两种病毒，然后按适当比例混合后制成联苗，这样既费时又费力，生产成本也较高。为此我们试用了在同一鸡胚内共培养的方法制备繁殖两种病毒并制备二联苗的尝试，取得了非常理想的效果，现报告如下。     

鸡新城疫-传染性支气管炎-传染性法氏囊三联苗的相关检测试验

鸡新城疫（NO）、传染性支气管炎（IB）和传染性法氏囊病（IBD）三种传染病通常采用相应的单苗进行多次免疫,不仅费工费时,频繁免疫接种还会引起鸡的应激反应。目前,国外已研制出鸡新城疫、传染性支气管炎和传染性法氏囊三联弱毒疫苗。近年来,国内也开展了这方面的研究工作,由于各地采用的毒株不同,制备工艺不同,病毒的培养方式也不一样,制备的鸡新城疫一传染性支气管炎一传染性法氏囊三联疫苗对鸡的免疫效果也不一样。     

鸡新城疫,传染性支气管炎二联活疫苗病毒含量的测定

鸡新城疫、传染性支气管炎二联活疫苗病毒含量的测定赵世军（辽宁省兽医生物药品厂，辽阳１１１０００）根据《兽医生物制品规程》（一九九二年版）（下称《规程》）的规定，鸡新城疫（ＮＤ）、鸡传染性支气管炎（ＩＢ）二联活疫苗的效力检验可用１０－３疫苗１ｍｌ，分别...     

鸡传染性支气管炎与新城疫病毒在SPF鸡胚上的相互干扰

鸡传染性支气管炎(1B)和鸡新城疫(ND)是鸡的二种主要病毒性传染病。一些科研单位曾对这两种病毒之间的相互关系作过不同程度的研究,所得结论也存在着一定的差异,为进一步阐明1BV与NDV之间的相互作用,本试验采用9日龄SPF鸡胚分别先后接种1BV与NDV,及其灭活病毒以求这两种病毒在鸡胚上的相互作用,旨在为养禽生产提供一些可供参考的依据。     

一株鸡肾型传染性支气管炎病毒的分离与鉴定

从山东某鸡场疑似肾型传染性支气管炎病死鸡的肾脏中分离到一株病毒,经SPF鸡胚连续传代、血凝试验、鸡新城疫干扰试验、鸡胚矮小化试验、RT—PCR鉴定和动物回归试验,初步确定该病毒为肾型传染性支气管炎病毒,并命名为SD1105株。     

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.     

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.     

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     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

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

Tropical Animal Health and Production -