MSB-1培养物上清液对体内MDV作用的研究

研究了马立克氏病肿瘤细胞系（ＭＳＢ－１）培养物上清液对体内鸡马立克氏病病毒（ＭＤＶ）增殖的影响，结果表明，该上清液对体内ＭＤＶ的增殖无明显抑制作用；相反，可增加ＭＤ的发病率。另外，试验中发现，６日龄鸡对ＭＤＶ的易感性明显高于１日龄鸡。     

MSB—1培养物上清液对体内MDV作用的研究

研究了马立克氏病肿瘤细胞系（ＭＳＢ－１）培养物上清液对体内马立克氏病病毒（ＭＤＶ）增殖的影响，结果表明，该上清液对体内ＭＤＶ的增殖无明显抑制作用，相反，可增加ＭＤ的发病率，另外，试验中发现，６日龄鸡对ＭＤＶ的易感性明显高于１日龄鸡。     

致病性马立克氏病病毒的污染与监测

马立克氏病（ Ｍａｒｅｋ’ｓ ｄｉｓｅａｓｅ，ＭＤ）是危害世界养禽业最严重的病毒性肿瘤性传染病。ＭＤ经羽毛囊排毒，空气传播，传染力极强，是鸡的三大主要疫病之一，可造成重大的经济损失。该病的致病因子为马立克氏病病毒（Ｍａｒｅｋ’ｓ ｄｉｓｅａｓｅｖｉｒｕｓ，ＭＤＶ），属疱疹病毒科成员，根据其嗜淋巴细胞性相似于γ－疱疹病毒，而其基因组结构却相似于α－疱疹病毒［１］。 ＭＤＶ按其致病性和血清学反应不同分为三个血清型：血清Ｉ型（ＭＤＶＩ）包括致瘤致病性的强毒株（如 ＨＰＲＳ－ １７、ＧＡ、Ｍｄ／５、ＢＪ－１）…     

鸡马立克氏病及其预防

鸡马立克氏病及其预防崔治中（扬州大学农学院动医系扬州２２５００９）自１９６７年发现鸡马立克氏病病毒（ＭＤＶ）以来，已有整整３０年了。在这期间，人类未能消灭ＭＤＶ，但ＭＤＶ也未能毁灭养鸡业。然而，这３０年的共存却并不是平和的。１疫苗在不断发展，ＭＤＶ也...     

马立克氏病基因工程苗可行性研究

马立克氏病基因工程苗可行性研究吴贤福，蔡宝祥（南京农业大学动物医学院２１００９５）近年来，由于马立克氏病强毒（ｖＭＤＶ）和超强毒（ｖｖＭＤＶ）的出现，使临床免疫过ＨＶＴ的鸡仍然发病，故有必要从免疫学角度反思ＭＤ防制问题。ＭＤ的免疫与免疫抑制同时并存，...     

鸡马立克氏病的现状及其防制

鸡马立克氏病（ＭＤ）是一种由疱疹病毒引起的具有高度传染性的肿瘤性疾病。我国于１９７３年首次发现ＭＤ,１９７８年开始生产用于预防ＭＤ的火鸡疱疹病毒（ＨＶＴ）疫苗。对有效地控制ＭＤ起了很大作用。鸡马立克氏病毒（ＭＤＶ）１９６７年发现至今已有３０年,由于病...     

马立克氏病研究的新进展：第五届国际马立克氏病会议介绍

马立克氏病研究的新进展——第五届国际马立克氏病会议介绍刘秀梵（扬州大学农学院２２５００９）第五届国际马立克氏病（ＭＤ）会议于１９９６年９月７日至１１日在美国密西根州立大学（ＥａｓｔＬａｎｓｉｎｇ）举行，密西根州立大学微生物系教授ＬｅｅｌａｎｄＶｅｌｉ...     

雏鸡HVT疫苗免疫后SOD活性的变化

雏鸡ＨＶＴ疫苗免疫后ＳＯＤ活性的变化＊迟玉杰李庆章（东北农业大学动物医学系，哈尔滨１５００３０）于洪祥（哈尔滨原种鸡场）在马立克氏病（ＭＤ）及其疫苗免疫的国内外研究中，马立克氏病病毒（ＭＤＶ）的分子生物学及病原诊断、疫苗研制及应用、ＭＤ病理等方面已取...     

5种马立克氏病疫苗免疫效力的对比试验

５种马立克氏病疫苗免疫效力的对比试验张建伟杨彦明周蛟（北京市农林科学院畜牧兽医研究所，１０００８１）自７０年代，研制出ＨＶＴ冻干疫苗并用免疫预防以来，马立克氏病（ＭＤ）的发生得到了很好的控制。几年后ＭＤ免疫失败就开始见有报道。８０年代又分别应用了改进...     

鸡马立克氏病疫苗研究和使用现状

鸡马立克氏病（ｍａｒｅｋ＇ｓＤｉｓｅａｓｅ,ＭＤ）是鸡的三大主要传染病之一,是由马立克氏病病毒（ＭＤＶ）引起的。以淋巴细胞增生为特征的恶性传染病,对养鸡业危害极大。据统计,仅１９８６年一年,世界各地所有鸡群由ＭＤ引起的直接或间接损失就在９亿美元,我国...     

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.     

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 -