应用PCR检测人工感染鸡体内鸡传染性贫血病毒的动态分布

应用聚合酶链反应技术检测人工感染１２周龄ＳＰＦ鸡体内鸡传染性贫血病毒的动态分布结果,感染后第２周可从外周血液白细胞中检出ＣＡＶ－ＤＮＡ,在第３周时达到最高峰,然后逐渐下降,第６周时检出率仅为６．３％,第７周以后均未能从血液白细胞中检测到ＣＡＶ－ＤＮＡ;人工感染后第２－１２周均能从骨髓,胸腺,脾,肾,肝和腔上囊等组织检出ＣＡＶ－ＤＮＡ,其中以骨髓和胸腺的检出率最高,其次脾,肾和肝,腔上囊最低,从１２     

水牛血液与肝组织中cAMP、cGMP与cAMP/cGMP的正常水平及其在感染肝片吸虫后的动态变化

选择２ ～３ 岁，体重３００～４００ ｋｇ 雄性健康去势水牛２０ 头。用放射免疫方法测定水牛血清和肝组织中ｃＡＭＰ和ｃＧＭＰ水平及其在感染肝片吸虫后的动态变化。结果表明：水牛血清ｃＡＭＰ、ｃＧＭＰ、和ｃＡＭＰ／ｃＧＭＰ正常水平分别为（２－１１ ±０．４６） ｎｍｏｌ／Ｌ，（０．８２ ±０．０７） ｎｍｏｌ／Ｌ和２．２０ ±０．４１ 。肝组织匀浆三者水平值分别为（０－３５±０－０４） ｎｍｏｌ／ｇ，（０－１５ ±０－０１） ｎｍｏｌ／ｇ，２－３８±０－３４。慢性感染条件下，感染后２ ～１１ 周，血清ｃＡＭＰ与ｃＡＭＰ／ｃＧＭＰ在高于对照组的范围内波动，ｃＧＭＰ水平则与对照组相近；肝组织匀浆的ｃＡＭＰ和ｃＧＭＰ均高于对照组。急性感染水牛血清ｃＡＭＰ在感染后３～７ 周期间低于或显著低于对照组，而ｃＧＭＰ在高于对照组波动，ｃＡＭＰ／ｃＧＭＰ比值在感染后１～１５ 周低于对照组；肝组织匀浆中的ｃＧＭＰ显著高于对照组，而ｃＡＭＰ／ｃＧＭＰ则显著低于对照组。结果提示，肝片吸虫感染能导致宿主的ｃＡＭＰ，ｃＧＭＰ和ｃＡＭＰ／ｃＧＭＰ比值紊乱。     

鸡贫血因子病全身免疫功能变化的研究

用鸡贫血病毒（ＣＡＶ）感染１日龄ＡＡ雏鸡,以未感染同龄ＡＡ雏鸡为对照,感染后不同时间检测其外周血液Ｔ、Ｂ细胞数量和ＩｇＧ,ＩｇＭ,ＩｇＡ含量,胸腺,法氏囊,脾脏ＩｇＧ,ＩｇＭ,ＩｇＡ抗体生成细胞和Ｔ细胞数量以及Ｔ、Ｂ细胞增殖功能;胸腺和脾脏白细胞介素２（ＩＬ－２）和干扰素（ＩＦＮ）诱生活性等的动态变化。     

兔烧伤合并海水浸泡后重要器官的病理变化

观察兔烧伤合并海水浸泡后，皮肤、心、肝、脾、肺、肾组织病理学变化特点，为兔烧伤合并海水浸泡后的早期救治提供依据。新西兰兔20只，制作烧伤动物模型后，随机分为浸泡组（n=10）和对照组（不经海水浸泡组，n=10）。光镜和电镜下观察兔烧伤合并海水浸泡后，皮肤、心、肝、脾、肺、肾组织病理学变化特点，并用HPIAS-1000病理分析系统对肝细胞进行测量。结果显示，兔烧伤合并海水浸泡后，皮肤、心、肝、脾、肺、肾组织病理学变化明显比对照组严重，肝细胞体积明显小于对照组。免烧伤合并海水浸泡后重要器官的病理变化有其自身特点，比其单纯烧伤后的病理变化明显加重。     

黄芪多糖和香菇多糖对vMDV感染雏鸡淋巴细胞化学发光的影响

１日龄雏鸡人工感染ｖＭＤＶ，并注射黄芪多糖（ＡＰＳ）和香菇多糖（Ｌｅｎ），分别于７、１６、２８、４２和５６日龄检测雏鸡淋巴细胞化学发光（ＣＬ）的变化。结果表明：（１）ＡＰＳ对７、１４日龄ｖＭＤＶ感染雏鸡胸腺、脾脏和法氏囊淋巴细胞的ＣＬ有显著抑制作用（ｐ〈０．０５，ｐ〈０．０１），在２８、４２日龄则显著增强淋巴细胞ＣＬ（ｐ〈０．０５，ｐ〈０．０１）；（２）Ｌｅｎ对７、１４日龄ｖＭＤＶ感染雏鸡胸腺、脾     

PCR和斑点杂交检测鸡传染性贫血病毒

通过聚合酶链反应（ｐｃＲ）扩增鸡传染性贫血病毒（ｃＡＶ）ＤＮＡ特定片段，将此ｐｃＲ产物用Ｄｉｇｏｘｉｇｅｎｉｎ标记后作为探针进行斑点杂交，以此检测ＣＡＶ并作流行病学调查。对从江苏省不同地市随机采集的２月龄左右不同疾病的病鸡ＤＮＡ样品进行检测，在被检的５２个不同鸡群来源的病料中，有３６个鸡群来源的病料ＤＮＡ显示ＣＡＶ阳性（群阳性率为６９．２％）；备组织中ＣＡＶＤＮＡ含量有所差异，依次为胸腺＞脾、骨髓、肝＞肾、法氏囊、脑。用ＰＣＲ检测得到的阳性鸡的组织病料感染ＳＰＦ鸡，在感染后第２４天检查，出现贫血症状。初步调查表明，在江苏一些地区ＣＡＶ感染已相当普遍，但它与发病的关系还有待于进一步研究。     

鸭瘟病毒弱毒株在免疫雏鸭体内的分布和排毒规律

鸭瘟病毒(DPV)弱毒Cha株经皮下、口服和滴鼻3种途径免疫1日龄雏鸭，应用聚合酶链反应(PCR)检测了病毒在体内分布和排毒规律。Cha株免疫雏鸭后，对血液、心、肝、脾、肺、肾、十二指肠、直肠、法氏囊、胸腺、胰腺、延脑、大脑、小脑、舌、肌肉、骨髓、粪便和食道共19种组织PCR检测结果如下：(1)皮下接种雏鸭后4h，即可在心、肝、脾、肾、法氏囊、胸腺、胰腺、延脑、大脑和小脑共10种组织中检出DPV的DNA；8h后，所有采取的组织器官均可检测到DPV的DNA。(2)口服接种雏鸭后4h，可在舌和食道中检测到DPV的DNA；8h后，可在心、肝、脾、肾、胸腺、胰腺、延脑、大脑、小脑、舌、食道和血液共12种组织器官中检出DPV的DNA。(3)滴鼻接种雏鸭后4h，未能在各种组织中检出DPV的DNA；8h后，可在心、肝、脾、肾、胸腺、延脑、大脑、小脑、舌、食道和血液共11种组织中检测到DPV的DNA。(4)在3种免疫途径中，检出时间最早和检出率最高的组织器官为肝脏、脑(大脑、小脑和延脑)；3种途径免疫的鸭，从免疫后12h至21d均能从所有采集的组织中检测出DPV DNA。     

不同佐剂对禽霍乱弱毒苗在鸡体内居留时间的影响

以不同佐剂处理的禽霍乱弱毒活菌液,胸肌接种鸡后,不同时间内剖杀试验鸡,分别采集注射部位、肝、脾、肾、肺、胸腺、胰、脑、法氏囊和心血等组织材料作巴氏杆菌分离。结果表明:(1)禽霍乱活菌在鸡体内器官居留时间十分短暂,在肝、脾、肾、肺居留时间最长只有1—2天;(2)不同时间剖杀试验鸡均末能从胸腺、胰、脑、法氏囊和心血等材料中分离到接种菌;(3)不同佐剂处理的活菌液在注射居留时间,以油佐剂的6—8天为最长,其次是铝胶佐剂的5天,不加任何佐剂的马丁汤稀释菌液在局部居留时间最短,只有1—2天。     

实验性水貂链球菌病研究

给水貂人工接种从患病水貂分离的链球菌ＭＳＺ株（Ｃ群）后，采集心、肝、脾、肾、脑和肌肉等器官组织制成标本，用光镜和荧光显微镜观察的结果为，本菌定位的靶器官为脾、肝、肺和心。     

鸡马立克氏病免疫抑制机理的研究

用马立克氏病强毒（ｖＭＤＶ）感染１日龄健康ＡＡ雏鸡，在感染后５、２５、４５日检测其胸腺、脾脏Ｔ细胞白细胞介素２（ＩＬ－２）诱生活性、ＩＬ－２受体（ＩＬ－２Ｒ）表达及Ｔ细胞增殖功能，胸腺、法氏囊、脾脏、盲肠、扁桃体、肺支气管粘膜淋巴组织及哈德尔腺中α－萘酚酯酶阳性Ｔ细胞、酸性磷酸酶阳性Ｔ细胞、抗体生成细胞数量，外周血液中Ｔ细胞数量、ＩｇＧ、ＩｇＭ、ＩｇＡ含量及泪液、气管液、肠液、胆汁中ＩｇＡ．ＩｇＧ、ＩｇＭ含量的动态变化。揭示了感染鸡细胞因子ＩＬ－２的免疫调节发生障碍，中枢与外周免疫器官的细胞免疫和体液免疫功能呈现抑制，呼吸道与消化道的局部免疫防御功能明显降低。     

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