鸭疫里氏杆菌和大肠杆菌二联灭活疫苗研究

将鸭疫里氏杆菌(RA)通过加有血清的改良肉汤培养，得菌数在520亿—2000亿／mL的菌液；鸭大肠杆菌(E．coli)通过普通肉汤培养，得菌数在1000亿～5000亿／mL的菌液，将两茵液甲醛灭活后以2.5：1的比例混合，再与灭菌的油乳剂以2：5的比例强力搅拌，制成二联油乳剂灭活疫苗，经无菌检验，安全检验合格后，做免疫保护试验，免疫6日龄雏鸭(0．5mL/只)，于18天后攻毒(RA：0．2mL／只；E.coli：0．1mL/只)，保护率分别为75％和50％；6日龄一免，14日龄二免(均0．5mL/只)，于二免后11天攻毒，保护率分别为100％和80％。     

鸭疫里氏杆菌病三价油乳剂灭活疫苗的研究

以1、2、10型鸭疫里氏杆菌（RA）分离株为菌种，研制鸭疫里氏杆菌病三价油乳剂灭活疫苗。经无菌及安全检验合格后，对6日龄樱桃谷雏鸭颈部皮下接种0.4mL／只,免疫后第10、14、21和35d分别用1、2、10型RA强毒株攻攻，第14d的攻毒保护率为91.7%-100%,35d攻毒保护率为66.6%-83.3%。田间试验结果表明，雏鸭5－7日龄免疫后至上市保护率可达95.0%-100%。     

鸭传染性浆膜炎铝胶疫苗研究

将鸭疫里氏杆菌通过改良酵母肉汤培养，得菌数在500－2000亿／ml的菌液：甲醛灭活，与氢氧化铝液（含量1.4%)2:1混合搅匀，制成铝胶疫苗，经无菌检验，安全检验合格，免疫5日龄雏鸭，分别于7d,10d,20d后攻毒（攻毒剂量：0.25ml），攻毒保护率为50％，50％，75％，5日龄，12日龄两次免疫，10日后攻毒保护率为10％。     

鸭浆膜炎、鸭病毒性肝炎二联灭活苗研究

将自然分离的2株鸭疫里默氏杆茵接种适宜培养基,收获茵液用甲醛灭活;用Ⅰ型鸭肝炎病毒(DHV)接种易感鸡胚收获含毒胚组液,经甲醛灭活后与灭活的鸭疫里默氏杆菌液混合,制备3批油乳剂灭活苗,并对其安全性和免疫原性进行测定。3批灭活苗通过接种2周龄雏鸭(0．5mL／只),2周后可测到DHV中和抗体,3周后攻毒保护率达80％以上。鸭疫里默氏杆茵3周后攻毒保护力80％以上。2周龄雏鸭每只皮下注射1ml,观察14d,免疫鸭全部健活,局部无不良反应。     

鸭传染性浆膜炎铝胶疫苗研制

将鸭疫里氏杆菌通过改良酵母肉汤培养,得菌数在500～2000亿/ml的菌液甲醛灭活,与氢氧化铝液(含量1.4%)21混合搅匀,制成铝胶疫苗,经无菌检验、安全检验合格,免疫5日龄雏鸭,分别于7d、10d、20d后攻毒(攻毒剂量0.25m1),攻毒保护率为50%、50%、75%;5日龄、12日龄两次免疫,10日后攻毒保护率为10%.     

鸭疫里氏杆菌蜂胶灭活疫苗的研制及临床应用

以从本地病番鸭群和樱桃谷鸭群中分离到的鸭疫里氏杆菌(RA),W-4和Z-3株为菌种,蜂胶为佐剂研制而成的鸭疫里氏杆菌蜂胶灭活疫苗,经无菌试验和安全性试验合格后,给6日龄雏鸭注射0.3mL/只,接种后10d用相应的2株强毒进行攻击,能获得80%以上的保护率,临床应用保护率在92%以上,疫苗经半年保存后,其物理性状仍均匀稳定。经临床应用证明它具有使用方便、安全、高效等特点。     

西南地区鸭疫里默氏菌血清型调查和三价灭活油乳剂疫苗的研制

本文对2006～2009年从四川、重庆、云南等主要养鸭区分离鉴定的261株鸭疫里默氏菌（RA）的血清型进行鉴定，结果显示血清Ⅰ、Ⅱ、Ⅳ型RA占总分离株的68．20％。筛选出免疫原性好的Ⅰ、Ⅱ、Ⅳ型RA分离株各1株，制备三价灭活油乳剂疫苗，安全性和效力检验结果显示该三价苗安全，接种后无不良反应，3日龄雏鸭首免后14～31d对Ⅰ、Ⅱ、Ⅳ的攻毒保护率均在83．33％以上。     

黄芪多糖佐剂对Ⅰ型鸭疫里氏杆菌灭活疫苗的作用研究

本研究以Ⅰ型鸭疫里氏杆菌武汉分离株为菌种,经复苏、增菌、浓缩、灭活后与黄芪多糖佐剂混合制成灭活疫苗。试验鸭在5日龄时按最佳免疫剂量（0.3 mL/只）注射疫苗,免疫后第3、7、10、14、21天的攻毒保护率分别为100%、90%、100%、100%、90%,免疫后第3天即能用琼脂扩散法在血清中检测出Ⅰ型鸭疫里氏杆菌特异性抗体,效价逐渐升高,至免疫后第10天达高峰（P<0.01）。试验结果表明,该灭活疫苗能有效预防鸭传染性浆膜炎。     

鸭疫里默氏杆菌贵州流行株蜂胶灭活疫苗制备

【目的】制备鸭疫里默氏杆菌(Riemerella anatipestifer,RA)贵州流行株蜂胶灭活疫苗。【方法】选取RA血清2型贵州流行株(RA-SS-8株)为基础菌株,依次利用分光光度法和平板计数法测定细菌生长曲线,再进行灭活条件筛选,以蜂胶为佐剂制备RA贵州流行株蜂胶灭活疫苗,并进行无菌检验、安全性检验及免疫鸭攻毒保护性试验。【结果】分光光度法测定RA-SS-8株菌液D_{600 nm}值随培养时间变化显示,细菌在0~3 h时增殖缓慢,在3~10 h时增殖趋势明显加快,在10 h以后增殖逐渐趋于平缓,随着培养时间的延长,细菌最终进入衰亡期;平板计数法结果显示,RA-SS-8株D_{600 nm}值为0.1~0.8时,该菌处于对数生长期,且D_{600 nm}值与活菌数呈现良好的线性关系;RA-SS-8株最佳灭活条件为0.2%甲醛溶液、37 ℃灭活12 h;蜂胶灭活疫苗含菌量为3.8×10⁹ CFU/mL,蜂胶干物质含量为10 mg/mL;无菌检验巧克力琼脂培养基上未见菌落生长;安全性检验以2倍免疫剂量接种雏鸭在观察期内未表现出不良反应,大体病变观察未见明显病变;免疫鸭攻毒保护性试验显示,蜂胶灭活疫苗免疫组鸭对RA-SS-8株的攻击后保护率为70%,蜂胶灭活疫苗对试验鸭心脏、肝脏组织均具有良好的保护效果。【结论】本研究成功制备了RA贵州流行株蜂胶灭活疫苗,为蜂胶灭活疫苗制备和动物免疫试验奠定基础。     

鸭疫里氏杆菌病灭活疫苗的研制

从河北省某肉鸭场的鸭疫里氏杆菌病发病鸭中分离出鸭疫里氏杆菌（Riemerella anatipestifer,RA)菌株。对该菌株采用液体、固体两种方法增菌培养后制成油乳剂灭活疫苗，以0.5mL/只剂量经皮下免疫7日龄雏鸭，并在河北省某发病肉鸭场进行了田间试验，表明该疫苗免疫效果良好，保护率达90％以上。     

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 -