免疫反应期间迷走神经放电的变化

采用免疫学方法和电生理实验技术，研究了免疫反应期间家兔迷走神经中枢端和外周端放电的变化。结果表明，结核菌素免疫后第５天，其细胞免疫反应达到高峰。迷走神经中枢端放电频率在免疫后第３天显著升高，第５天达到高峰；迷走神经外周端放电频率在免疫后第１天即开始升高，第３天达到高峰，第５天趋于恢复。此结果提示，在免疫反应期间，迷走神经传入、传出冲动均增加，增加的传出冲动发挥免疫促进效应，而增加的传入冲动可能具有向中枢传递免疫反应信息的功能。     

鸡传染性鼻炎与鸡毒支原体类脂灭活疫苗的研制

杨树皮类脂（PoplarBarkLipid）系从杨树皮中提取的一种橙黄色脂溶性物质，富含大量的多糖、有机酸、甾醇、磷脂、甙类及维生素等物质。多糖类具有促胸腺体液反应、刺激网状内皮系统，提高机体特异性免疫反应能力；有机酸具有增强机体免疫功能的作用，能够刺激和促进单核吞噬细胞功能，对抗免疫抑制对免疫器官的抑制作用；甙类能够加速抗体的产生、促进淋巴细胞转化和增强网状内皮系统功能等作用。这些物质在动物体内协调统一，大大提高动物体的免疫机能。副鸡嗜血杆菌（Hpg）作为鸡传染性鼻炎的病原菌，近年来发生率越来越高。由于该病在…     

采用弱毒活疫苗加强免疫

采用弱毒活疫苗加强免疫，通常是根在产蛋期间采用新城疫（ND）或传染性支气管炎（IB）弱毒活疫苗加强免疫接种，以提高免疫保护力。对免疫学机理的研究清楚地表明：活疫苗加强免疫接种能够刺激机体的细胞免疫与体液免疫，包括增强局部免疫反应（眼、气管）与循环（血液）抗体的保护水平。在鸡群生长期继适当的弱毒活疫苗营免后，采用灭活疫苗加强免疫仅能够刺激机体产生一致的高水平的循环抗体，这些高效价的抗体随着时间的推移而逐渐消失，从而对老龄鸡群相对缺乏保护力。为什么局部免疫保护如此重要？因为试验结果证实：即使在测不出循…     

维生素营养水平对鸡免疫功能的影响

1脂溶性维生素 1．1维生素A 目前许多研究表明，维生素A可显著提高鸡的免疫功能。维生素A可直接作用于B细胞。增强机体可溶性或颗粒性抗原产生的体液免疫功能，参与和促进抗体的合成，促进淋巴细胞转化，刺激白细胞介素和干扰素的分泌，诱导淋巴细胞增殖，促进吞噬细胞处理抗原和辅助性T细胞的成熟。增强机体的细胞免疫功能。     

病菌净Ⅱ对小鼠T淋巴细胞酯酶染色率的影响试验

本试验观察了中药复方病菌净Ⅱ对小鼠Ｔ淋巴细胞酯酶染色率的影响。结果，力净Ⅱ能提高小鼠Ｔ淋巴细胞酯酶染色率，与对照组比较，差异极显著（Ｐ〈０．０１）。研究结果表明：中药复方病菌净Ⅱ有增强机体细胞免疫功能的作用。     

鸡传染性鼻炎与鸡毒支原体类脂灭活苗的研制

杨树皮类脂(Poplar Bark Lipid)系从杨树皮中提取的一种橙黄色脂溶性物质，富含大量的多糖、有机酸、甾醇、磷脂、甙类及维生素等物质。多糖类具有促胸腺体液反应、刺激网状内皮系统，提高机体特异性免疫反应能力；有机酸具有增强机体免疫功能的作用，能够刺激和促进单核吞噬细胞功能，对抗免疫抑制对免疫器官的抑制作用；甙类能够加速抗体的产生，促进淋巴细胞转化和增强网状内皮系统功能等作用。这些物质在动物体内协调统一，大大提高动物体的免疫机能     

维生素营养水平对鸡免疫功能的影响

目前许多研究表明，维生素A可显著提高鸡的免疫功能。维生素A可直接作用于B细胞，增强机体可溶性或颗粒性抗原产生的体液免疫功能，参与和促进抗体的合成，促进淋巴细胞转化，刺激白细胞介素和干扰素的分泌，诱导淋巴细胞增殖，促进吞噬细胞处理抗原和辅助性T细胞的成熟，增强机体的细胞免疫功能。某些传染性疾病如球虫病、蠕虫病等可降低维生素A原在体内转化成维生素A，从而导致维生素A缺乏。     

鸡转移因子的制备及应用研究 Ⅱ.对细胞免疫及体液免疫的影响

用淋巴细胞转移试验监测细胞免疫效果，用血凝抑制试验监测体液免疫效果，结果表明，注射鸡转移因子的实验组与注射生理盐水的对照组。其细胞免疫和体液免疫功能均有显著差异。说明鸡转移因子具有良好的生物活性，对Ｔ细胞免疫和Ｂ细胞免疫都具积极作用，可促进机体产生良好的免疫效果，增强机体的免疫功能。     

日粮中添加谷氨酰胺对肉仔鸡法氏囊发育的影响

谷氨酰胺（Glutamine，GLN）是体内组织间的氮前体穿梭工具，是快速增殖细胞（淋巴细胞和肠黏膜细胞）的主要能源物质，参与体内抗氧化剂-谷胱甘肽（GSH）的合成。具有维持肠道机能，提高机体免疫功能，改善酸碱平衡失调和提高机体对应激的适应等多种生理功能。GLN对机体免疫功能的作用已受到诸多学者关注：Ardawi等体外培养大鼠淋巴细胞发现，添加GLN可显著提高淋巴细胞的增殖；O’Riordain MG等证实，GLN能显著增强结肠、直肠切除病人体内T淋巴细胞DNA的合成。     

免疫调节剂研究进展

免疫佐剂（Immunologicadjuvant）是指先与抗原或抗原物质混合后注射，能非特异性增强或改善机体对抗原物质特异性免疫应答的一类物质。免疫调节剂（Immunomodulator）是广义上免疫佐剂，其特点是具有双向免疫反应调节功能，即对于不同免疫状态下的机体可作为免疫增强剂提高免疫反应，或作为免疫抑制剂降低机体免疫反应性。目前免疫调节剂已在疾病防治上显示出特殊的应用价值，现将其应用作一综述。１多糖类免疫调节剂１．１香菇多糖（Lentinan）香菇多糖是从香菇子实体中提取、分离、纯化获得的多糖。它在抑制肿瘤生长、转移及增强机体对…     

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 -