分泌抗赭曲霉素A单克隆抗体杂交瘤细胞株的建立

用赭曲霉素Ａ（ＯＡ）－ＢＳＡ合成抗原免疫Ｂａｌｂ／ｃ小鼠，取免疫鼠脾细胞与ｓｐ２／０细胞融合，通过克隆和ＥＬＩＳＡ法筛选，建立三株泌抗ＯＡ单克隆抗体杂交瘤细胞株（３Ｃ１２，１Ｄ１２和２Ｇ７）。用间接ＥＬＩＳＡ法测定，细胞上清液抗体效价为１２８＾×（３Ｃ１２）和６４＾×（１Ｄ１２和２Ｇ７）腹水抗体效价为１０＾－７（３Ｃ１２，１Ｄ１２）和１０＾－６（２Ｇ７）。三株单抗（ＭｃＡｂ）均属ＩｇＧ类，分泌抗体     

具有中和活性的减蛋综合征病毒单抗的研制

用减蛋综合征病毒毒株ＷＰＤＶ２０５纯化抗原免疫ＢＡＬＢ／ｃ小鼠，在最后一次免疫后第３天取脾细胞与ＳＰ２／０细胞在ＰＥＧ－４０００的作用下融合。用间接ＥＬＩＳＡ初步筛选出阳性克隆１０株（４Ｂ１、１Ｄ４、２Ｄ６、３Ｄ６、３Ａ５、２Ａ１、３Ｃ６、３Ｃ１、１Ｂ３和２Ｃ５）。这些杂交瘤细胞经克隆化和再次检测后生产腹水，用微量细胞中和试验筛选出具有中和活性的单克抗隆体４株（４Ｂ１、３Ｃ１、３Ｃ６和２Ｃ５），其     

抗鸡传染性法氏囊病病毒单克隆抗体中和株的建立

将纯化的鸡传染性法氏囊病病毒（ＩＢＤＶ）组织毒免疫的ＢＡＬＢ／ｃ鼠脾细胞与ＳＰ２／０骨髓瘤细胞融合，用ＥＬＩＳＡ，病毒中和试验检测分泌抗体，获得了６株稳定分泌抗ＩＢＤＶ单隆抗体的杂交瘤细胞，命名为ＮＩＢ－１，ＮＩＢ－２，ＮＩＢ－３，ＮＩＢ－４，ＮＩＢ－５，ＮＩＢ－６；６株ＭＣＡｂ均具ＥＬＩＳＡ特性和免疫沉淀特性，亚类鉴定表明，前４株属于ＩｇＧ２ａ，后２株属于ＩｇＧ１。杂交瘤细胞冻存６个月后复苏，均     

抗绵羊肺炎支原体单克隆抗体杂交瘤细胞株的建立

用绵羊肺炎支原体抗原免疫的ＢＡＬＢ／Ｃ小鼠，取血清抗体阳性免疫鼠的脾细胞与ＳＰ２／Ｏ细胞在聚乙二醇作用下进行融合，产生杂交瘤细胞、用间接ＥＬＩＳＡ法对杂交瘤一长孔上清液进行检测，筛阳性交瘤细胞株。     

抗绵羊肺炎支原体单克隆抗体杂交瘤细胞株的建立

用绵羊肺炎支原体（ＭＯ）抗原免疫的ＢＡＬＢ／Ｃ小鼠，取血清抗体阳性免疫鼠的脾细胞与ＳＰ２／Ｏ细胞在聚乙二醇作用下进行融合，产生杂交瘤细胞、用间接ＥＬＩＳＡ法对杂交瘤细胞生长孔上清液进行检测，筛选阳性杂交瘤细胞株．以有限稀释法克隆１～２次，得到６株分泌抗绵羊肺炎支原体抗原的单克隆抗体（ＭｃＡｂ）杂交瘤细胞株．选择抗体分泌较高的１４Ａ６、７Ａ２７、Ｂ３８进行了较详细的研究，结果表明，其核内染色体数为９４～９６．抗体属性是：１株为ＩｇＧ２ａ、２株为ＩｇＧ１．用间接ＥＬＩＳＡ法对３株ＭｃＡｂ作符异性分析、该ＭｃＡｂ只特异地与绵羊肺炎支原体抗原发生反应，而不与猪肺炎支原体、山羊无乳症支原体抗原发生反应．将杂交瘤细胞注射ＢＡＬＢ／Ｃ小鼠诱生腹水．其抗体效价提高１００倍．杂交瘤细胞在液氮中保存１～２年后复苏仍能稳定地分泌抗绵羊肺炎支原体ＭｃＡｂ。     

抗兔轮状病毒单克隆抗体杂交瘤细胞株的建立

用小鼠骨髓瘤细胞与经兔轮状病毒免疫的ＢＡＬＢ／ｃ系小鼠脾细胞进行融合，融合成功率为２２％。经间接酶联免疫吸附试验和斑点酶联免疫筛选杂交瘤细胞，阳性率为２９％左右。对其中６株强阳性的杂交瘤细胞进行了亚克隆，获得高产亚克隆杂交瘤细胞，用ＢＡＬＢ／ｃ小鼠生产了腹水，鉴定后选取２株强阳性高效价的杂交瘤细胞，以ＥＬＩＳＡ阻断试验检验其分泌抗体的特异性，以直接ＥＬＩＳＡ测其敏感性，用琼脂双扩散试验鉴定类和亚类     

一种快速有效制备单克隆抗体的方法

以人绒毛膜促性腺激素（ｈＣＧ）为抗原,对ＢＡＬＢ／ｃ小鼠一次脾内直接注射免疫,免疫后６ｄ,取其血清进行抗体检测,结果１２８００倍稀释度仍呈阳性。取此免疫小鼠脾细胞与同系小鼠骨髓瘤细胞ＮＳ－１进行细胞融合。融合后,将经检测抗体阳性的细胞孔置于显微镜下,挑选单个克隆进行克隆化,得到２株单克隆抗体细胞株２Ａ８、４Ｅ６。将其分别接种于ＢＡＬＢ／ｃ小鼠腹腔中,收获的腹水效价分别达１０－６和１０－５。     

猪繁殖与呼吸道综合征病毒(PRRSV)单克隆抗体的研制

利用猪繁殖与呼吸道综合征病毒（ＰＲＲＳＶ）国内分离株Ｊ１,采用反复差速离心法制备免疫抗原,长程免疫法免疫ＢＡＬＢ／ｃ小鼠,用间接ＥＬＩＳＡ方法检测抗体,通过细胞融合技术,并经３次亚克隆获得了１０株能稳定分泌抗ＰＲＲＳＶ单抗的杂交瘤细胞单克隆株（Ａ１Ｄ７Ｈ１０,Ａ１Ｄ７Ｈ１１,Ａ１Ｅ７Ｈ９,Ａ１Ｅ７Ｄ９,Ａ２Ｄ８Ｅ７,Ａ２Ｄ８Ｂ１１,Ｂ３Ｄ１１Ｄ６,Ｂ２Ｇ９Ａ９,Ｂ２Ｇ９Ｆ２）。这些细胞经体外连续传     

猪T细胞表面抗原特异性单克隆抗体的研制及其特性鉴定

用从健康猪胸腺提取的 Ｔ 淋巴细胞作抗原免疫 Ｂ Ａ Ｌ Ｂ／ｃ 小鼠。取免疫鼠脾细胞与 Ｓ Ｐ２／０ 骨髓瘤细胞融合，经 ３ 次克隆，共获得 １０ 株稳定分泌抗体的杂交瘤细胞。以细胞反应特异性试验、 Ｗ ｅｓｔｅｒｎｂｌｏｔｔｉｎｇ 分析、流式细胞计数（ Ｆ Ｃ Ｍ ）等方法，确定了对猪 Ｔ 细胞表面抗原特异性反应的单抗（ Ｍ ｃ Ａｂｓ），其中 ２ Ｄ９ 、３ Ｂ１ ０ 可以识别相对分子质量 ５０ ０００ 的 Ｔ 细胞膜蛋白，能标记 ９６％ 的胸腺细胞、８９％ 的外周血 Ｔ 淋巴细胞、８７％ 的脾 Ｔ 淋巴细胞，其特性与猪 Ｃ Ｄ２ 抗原相符；另一株 １ Ｇ１ ２ 可识别相对分子质量 ６３ ０００ 的 Ｔ 细胞膜蛋白，能标记 ９８％ 的胸腺细胞、９１％ 的外周血 Ｔ 淋巴细胞、７８％ 的脾 Ｔ 淋巴细胞，其特性与猪 Ｃ Ｄ５ 抗原相符。     

分泌抗兔出血症病毒单抗杂交瘤细胞株的建立

以纯化的兔出血症病毒免疫ＢＡＬＢ／Ｃ鼠，应用杂交瘤技术获得了分泌抗ＲＨＤＶ单抗杂交瘤细胞１７株，其中有３株杂交瘤细胞分泌单抗的ＥＬＩＳＡ效价为１：４０９６００，１：４０９６；５株单抗具有血凝抑制活性。兔抗ＲＨＤＶ高兔血清对１７株ＭｃＡｂ的ＥＬＩＳＡ抑株为ＩｇＧ２ｂ。各株ＭｃＡｂ与欧洲棕色兔病病毒无抗原交叉反应，也无沉淀反应特性。     

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.     

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     

Evaluation of the Microbiological Status of Milk and Various Structures in Mammary Glands from Naturally Infected Dairy Cows

A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.     

Development and survival of free-living stages of gastrointestinal nematodes of sheep and goats on pasture in the Nigerian derived savanna

Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L₃) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L₃ developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.