柔嫩艾美球虫常州株对5种抗球虫药的抗药性分析

将柔嫩艾美耳球虫(E.tenella)常州分离株感染14日龄苏禽黄羽肉鸡,设立5个用药组、1个感染不用药对照组和1个不感染不用药对照组,以相对卵囊产量、病变记分减少率、最适抗球虫百分数和抗球虫指数为指标对该虫株对球虫宁、地克珠利、马杜霉素、磺胺氯吡嗪、癸氧喹酯5种常用抗球虫药的抗药性进行了综合评定,分析了该地区球虫的抗药性及用药对策。结果表明,该虫株对癸氧喹酯敏感,对球虫宁、地克珠利、马杜霉素、磺胺氯吡嗪具有完全抗药性,提示目前常州地区球虫抗药性非常严重,癸氧喹酯抗球虫疗效最好,其他药物应合理使用、应慎用、减少或暂停使用。     

癸氧喹酯抗柔嫩艾美耳球虫山东临沂分离株的效果观察

目前,集约化养鸡业中控制鸡球虫病的主要手段仍以药物防治为主.癸氧喹酯是喹啉类新型抗球虫药,在临床上有独特的抗球虫活性,可用于防治鸡的柔嫩、毒害、堆型、巨型等艾美耳球虫引发的球虫病.临沂地区近年来养鸡业得到很大发展,但癸氧喹酯在该地区使用较少,因此,研究该药抗柔嫩艾美耳球虫临沂分离株的效果,可为临沂地区临床上合理选用该药提供依据.     

癸氧喹酯预混剂

癸氧喹酯在球虫生活史的早期开始发挥作用,且持续作用时间最长。抗球虫谱广。对危害最大的6种禽球虫都有良好的效果。通过添加非离子表面活性剂、元明粉将癸氧喹酯制成干混悬剂,解决了癸氧喹酯因不能饮水给药的使用限制问题,大大提高了癸氧喹酯药物的临床应用范围。有广泛的的应用前景。     

癸氧喹酯溶液预防人工感染肉仔鸡球虫病的药效试验

研究了癸氧喹酯溶液对肉鸡球虫病的预防效果。结果表明,癸氧喹酯溶液按15mg/kg饮水,抗球虫指数为190．属高效抗球虫药物。     

癸氧喹酯抗柔嫩艾美耳球虫洛阳分离株的效果试验

以抗球虫指数(Anticoccidial Index,ACI)、料肉比及增重为指标,研究了癸氧喹酯抗鸡柔嫩艾美耳球虫洛阳分离株的效果.结果表明,根据54.4 mg/kg、27.2 mg/kg、13.6 mg/kg体重的剂量按饲料比拌料给药,抗球虫指数(ACI)分别达到183.57、145.53和127.80,与感染不给药组相比,料肉比分别降低30.04％、10.60％和3.18％,高剂量组增重与不感染对照组没有显著差异.癸氧喹酯以54.4 mg/kg体重的浓度拌料可以预防洛阳地区鸡球虫病感染,试验结果为临床上有效利用癸氧喹酯控制鸡球虫病提供了重要依据.     

柔嫩艾美耳球虫癸氧喹酯耐药株的诱导研究

采用药物浓度递增法,在实验室条件下进行柔嫩艾美耳球虫耐药虫株的诱导。以5.4 mg/kg癸氧喹酯为起始诱导浓度连续传代,以病变记分减少率(RLS)、最适抗球虫指数(POAA)和抗球虫指数(ACI)3项指标综合判定耐药性,经9次传代,成功地诱导出对54 mg/kg癸氧喹酯具有完全抵抗力的耐药虫株,为进一步的球虫耐药的分子机理研究提供材料。     

巨型艾美耳球虫和柔嫩艾美耳球虫早熟株对8种抗球虫药的敏感试验

为检测巨型艾美耳球虫和柔嫩艾美耳球虫早熟株对常用抗球虫药的敏感性,选用地克珠利、氯苯胍、二硝托胺、癸氧喹酯、尼卡巴嗪、马杜米星、盐霉素和拉沙洛西等8种抗球虫药进行鸡体试验,通过抗球虫活性百分比（percent of optimum anticoccidial aetivity,POAA）、病变记分减少率（reduction of lesion scores,RLS）、相对卵囊产量（relative oocyst production,ROP）和抗球虫指数（anticoccidial index,ACI）4项指标进行综合评价。结果表明,巨型艾美耳球虫早熟株对8种药物敏感;柔嫩艾美耳球虫早熟株对盐霉素轻度敏感,对地克珠利、氯苯胍、二硝托胺、癸氧喹酯、尼卡巴嗪、马杜米星和拉沙洛西敏感。本研究结果可为对球虫早熟株疫苗的开发与应用提供实验依据。     

柔嫩艾美耳球虫莆田株抗药性研究

为掌握鸡场球虫抗药程度,以便制定合理用药方案,采集福建省莆田市某鸡场盲肠球虫,进行柔嫩艾美耳球虫单卵囊分离和纯化;采用鸡体试验法,设立5个用药组、1个感染不用药对照组和1个不感染不用药对照组,以病变记分减少率(Reduction of lesion sores,RLS)、抗球虫指数(Anticoccidial index,ACI)、相对盲肠卵囊产量(Relative at oocyst production,ROP)和最适抗球虫活性百分率(Percent of optimum anticoccidial activity,POAA)4项为指标,检测该球虫对癸氧喹酯、尼卡巴嗪、地克珠利、二硝托胺和氯苯胍等5种常用抗球虫药的抗药性。结果表明:该虫株对癸氧喹酯敏感,对地克珠利、二硝托胺和氯苯胍具有完全抗药性,对尼卡巴嗪为中度抗药性,说明目前莆田市球虫抗药性非常严重,癸氧喹酯可用于抗球虫病,其他药物应慎用或暂停使用。     

新型抗球虫药——癸氧喹酯的研究与应用

挑选健康且体况相近的180只14日龄黄羽肉鸡180只随机分组,在人工感染E.tenella条件下,评估癸氧喹酯、马杜米星铵、尼卡巴嗪乙氧酰胺苯甲酯及甲基盐霉素的抗球虫效果,并对4种抗球虫药物进行比较,以抗球虫指数（ACI）作为药物治疗效果的综合评定指标。结果显示,各药物组的ACI分别为癸氧喹酯194.53,马杜米星铵190.15,尼卡巴嗪乙氧酰胺苯甲酯189.87,甲基盐霉素165.42,未用药的感染对照组的ACI为112.23。癸氧喹酯和马杜米星铵的抗球虫效果最好,抗球虫指数超过190。     

4种抗球虫药防制鸡艾美耳球虫的试验

挑选健康和体况相近的180羽14日龄黄羽肉鸡,随机分组,在人工感染鸡艾美耳球虫条件下,评估癸氧喹酯、马杜米星铵、尼卡巴嗪乙氧酰胺苯甲酯及甲基盐霉素的抗球虫效果,并对4种抗球虫药物进行比较,以抗球虫指数(ACI)作为药物治疗效果的综合评定指标。结果显示,各药物组的ACI分别为癸氧喹酯194.53,马杜米星铵190.15,尼卡巴嗪乙氧酰胺苯甲酯189.87,甲基盐霉素165.42,未用药的感染对照组ACI为112.23。癸氧喹酯和马杜米星铵的抗球虫效果最好,ACI>190。     

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 -