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为了选育堆形艾美耳球虫（Eimeria acervulina）早熟株及观测其生物学特性,运用Jeffers创立的艾美耳属球虫早熟株选育方法,对实验室保存的堆形艾美耳球虫进行连续传代早熟选育,并对获得的早熟株与母株孢子化卵囊大小、繁殖能力、致病性以及免疫保护力等指标进行了测定,比较堆形艾美耳球虫早熟株与母株之间的基本生物学特性差异。经过18代早熟选育后,堆形艾美耳球虫的潜在期由母株的99h缩短至84h。与母株相比,早熟株的孢子化卵囊大小明显减小（P〈0．05）,卵囊繁殖能力降低了17％～42%。致病性试验中,早熟株感染组的平均增重均高于母株,而病变记分相当。免疫保护试验中,早熟株与母株的免疫保护力相当,其卵囊抑制率略低于母株,差异不明显（P〉0．05）。结果表明,本研究成功选育出堆形艾关耳球虫早熟株,对母株攻击具有保护力,为鸡球虫疫苗的研制奠定了基础。 相似文献
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为了选育巨型艾美耳球虫(Eimeria maxima)早熟株并观测其生物学特性,运用Jeffers创立的球虫早熟株选育方法,对实验室保存的E.maxima进行了早熟株选育,并比较了所获得的早熟株与母株在卵囊大小、繁殖能力、致病性、免疫保护力等生物学特性上的差异。经过17代早熟株选育,E.maxima的潜在期由母株的142 h缩短至107 h,缩短了35 h。早熟株卵囊的长、宽及大小均比母株小,且差异显著(P0.05);卵囊形状指数比母株的稍大,但差异不显著(P0.05)。早熟株的卵囊繁殖能力较母株的低,排卵囊高峰出现在接种后d6,较母株提前1 d。在同等剂量之下,早熟株的致病性低于母株,但免疫保护力和免疫原性与母株相当。早熟株的选育成功,为球虫早熟株弱毒疫苗的研制以及早熟株相关基因的筛选提供了重要材料。 相似文献
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鸡和缓艾美耳球虫早熟虫株选育及其生物学特性研究 《畜牧与饲料科学》2016,37(9):15-15
按照Jeffers1975年建立的艾美耳属球虫早熟虫株选育方法,对鸡和缓艾美耳球虫巴彦淖尔株（SY-MB株）进行了单卵囊分离、扩增和早熟虫株的选育。经SPF鸡15代传代之后,分离株的潜隐期由96 h缩短至77 h,缩短了19 h。按索勋等1998年建立的方法对选育出的和缓艾美耳球虫巴彦淖尔早熟株（SY-mb77株）进行10代非选择性传代,证明该早熟虫株的潜隐期、卵囊产量、免疫原性和致病性均具备早熟虫株特性,并能有效抵抗强毒虫株的攻击。 相似文献
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按照Jefiers 1975年建立的艾美耳球虫属球虫早熟选育方法,对和缓艾美耳球虫保定株进行了早熟选育。通过连续11代的早熟选育后,获得了潜隐期由97h缩短至82h的早熟系。该早熟系经过5代连续非早熟选择性传代,潜隐期仍稳定在82h。排卵囊期为感染后第4~10天,其中第5天为高峰期。该早熟系的致病力较亲本株弱,同样剂量感染后早熟系感染组相对增重率显著高于亲本株感染组。该早熟系免疫原性良好,每羽鸡免疫100个以上卵囊即可较好抵抗1x10^5个亲本株的攻击,相对增重率达80.0%以上和卵囊减少率达90.0%以上。 相似文献
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采用单卵囊分离技术,从河北省保定市暴发球虫病的某鸡场鸡粪便中成功分离出1株和缓艾美耳球虫(Eimeria mitis),并对其生物学特性和致病性进行了研究。该虫株主要寄生于小肠后段,潜隐期为97 h,孢子化时间为22 h,卵囊呈球形,平均大小为15.9μm×14.4μm,卵囊指数为1.10,PCR鉴定为纯种的和缓艾美耳球虫,将其命名为和缓艾美耳球虫保定株。该虫株排卵期为感染后第4～10天,其中第5～6天为高峰期。SPF鸡分别感染5×10~4个、1×10~5和2×10~5个和缓艾美耳球虫保定株孢子化卵囊后,均出现精神不振、排水样粪便等球虫病引起的临床症状,且各组相对增重率分别为78.5%、63.5%和59.3%,明显低于空白对照组,该虫株具有一定的致病性,表现为发病和减重。 相似文献
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本试验分离获得了1株巨型艾美耳球虫，通过紫外线诱导和非紫外线诱导两种方法对该虫株进行早熟选育，获得了2个巨型艾美耳球虫早熟减毒株。通过对2个早熟株的潜隐期、繁殖力、致病力以及免疫原性进行对比研究，证明紫外线诱导下的早熟选育可明显缩短选育所需代数，且与传统方法选育的早熟株在繁殖力、免疫原性与免疫保护力等方面基本相同。紫外线诱导下，经7代早熟选育，潜隐期由母株的142h缩短到116h，而非紫外线诱导的选育需要20代才能达到同样的选育结果。两早熟株卵囊的繁殖能力与母株相比有所下降，但仍保留了母株原有的免疫原性。 相似文献
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Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
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. 相似文献
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Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引：1，自引：0，他引：1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
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. 相似文献
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Waruiru RM Thamsborg SM Nansen P Kyvsgaard NC Bogh HO Munyua WK Gathuma JM 《Tropical animal health and production》2001,33(3):173-187
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. 相似文献
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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. 相似文献
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Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ 
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下载免费PDF全文 S. Pashaei T. Ghoorchi A. Yamchi 《Journal of animal physiology and animal nutrition》2016,100(2):211-216
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. 相似文献
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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 相似文献
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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. 相似文献
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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. 相似文献
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Acute phase proteins in dogs naturally infected with the Giant Kidney Worm (Dioctophyme renale) 下载免费PDF全文
下载免费PDF全文 Elizabeth M. S. Schmidt Mads Kjelgaard‐Hansen Funmilola Thomas Asta Tvarijonaviciute José J. Cerón P. David Eckersall 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(4):657-664