湘西黄牛发情周期生殖激素变化规律

为了了解生殖激素分泌规律,研究其作用机理,进一步提高家畜的生产性能,试验采集湘西黄牛母牛的血液样品,通过酶联免疫吸附技术测定其在发情周期中促卵泡素(FSH)、促黄体素(LH)、雌二醇(E_2)、孕酮(P_4)等激素的水平。结果表明:湘西黄牛的发情周期中,FSH浓度水平为4.92~7.31 m IU/m L,呈先下降后上升的变化趋势;LH浓度水平变化相对平缓,浓度为4.23~6.98 m IU/m L;E2水平变化相对平缓,浓度为16.75~24.33 pg/m L;P4浓度变化非常明显,大致呈先上升后下降的趋势,浓度为0.36~14.85 ng/m L。说明在发情周期中湘西黄牛血清中FSH和孕酮变化规律较明显,而LH和E2水平较平稳。     

中国美利奴军垦型细毛羊正常发情周期内血清孕酮含量的变化

采用放射免疫测定法(RIA),对中国美利奴军垦型细毛羊血清中孕酮(P4)浓度进行了检测,结果表明,繁殖母羊在休情期小于0.1ng/mL,发情排卵当天(0d)为0.236ng/mL,发情后(+1d)孕酮水平显著增高,达到5.25ng/mL,(0d)和(+1d)的孕酮含量差异十分显著(P＜0.01).提示该品种羊发情周期中卵巢的机能活动或生殖特性,可能与其它细毛羊存在一定差异.     

广西水牛唾液和血清生殖激素在发情周期的变化规律及相关性分析

[目的]对广西水牛发情周期唾液和血液中雌激素(E2)和孕酮(P4)的浓度变化规律及相关性进行了分析,为进一步探讨水牛发情规律来指导生产提供依据。[方法]采用酶联免疫分析方法(ELISA)测定发情母水牛血液和唾液中E2(雌二醇)和P4(孕酮)的浓度变化,并对血液和唾液的激素变化规律进行了相关性分析。[结果]广西水牛血液和唾液中的E2和P4呈波动性变化,结果表明,发情前期,唾液中P4浓度一直维持在6.57.1ng/mL,第13天达到11.09ng/mL以上,随后快速下降。唾液中E2浓度在发情前期第35天出现一个峰值178.528pg/mL,在1417d唾液中E2浓度显著升高,出现第二个峰值达到120.57pg/mL。唾液E2和P4浓度的变化趋势和血清E2和P4浓度的变化趋势基本一致,相关性较好。母水牛唾液和血清样品的P4浓度相关性显著(R=0.4080;P0.05),母水牛唾液和血清标本的E2浓度相关性显著(R=0.5113;P0.05)母水牛唾液E2和P4浓度相关性非常显著(R=0.7754;P0.01)。[结论]唾液和血液中的这两种激素水平起伏变化基本趋于一致,其相关性显著,可以作为监测水牛发情及预测排卵的可靠指标之一。     

怎样搞好母牛的秋季配种

1抓秋膘,促进母牛发情排卵8~10月是母牛秋季发情配种旺季。母牛应做到“使役繁殖两不误”。配种期到来时,适龄母牛应具有中等膘情的体况。过肥或过瘦均不利于配种,对瘦牛采用配合饲料玉米40%、大麦30%、小麦20%、黄豆10%混匀后,清水浸泡4~6h磨浆,添加以上饲料总量8%~10%的豆饼,5%糠麸,1%的食盐,3%~5%的骨粉,每天分早晚2次给牛补喂,每次连汤带水补喂7.5~10kg,并延长放牧时间,割草喂牛,使母牛在短期内发情配种。2抓时机,给发情母牛配种母水牛的发情周期为18~25d,持续2~4d。黄牛的发情周期18~21d,持续1~2d。母牛发情后食欲减少,兴奋不安,阴部潮…     

孕酮免疫生物传感器在奶牛上的临床应用

为了解孕酮免疫生物传感器的临床应用效果,本试验对7头妊娠奶牛,8头产后发情奶牛和18头乏情奶牛的血浆雌二醇、促黄体素、促卵泡素和孕酮浓度进行了检测,同时应用的孕酮免疫生物传感器进行了乳汁孕酮检测。结果显示,孕酮免疫生物传感器检测的乳汁孕酮水平与ELISA检测血浆孕酮含量之间呈正相关。该优化的生物传感器检测奶牛妊娠的孕酮浓度范围为10~15 ng/mL,发情的孕酮浓度范围为4~10 ng/mL;持久黄体的孕酮浓度范围为10~16 ng/mL,卵巢静止的孕酮浓度范围为3~7 ng/mL,黄体囊肿的孕酮浓度范围为12~18 ng/mL。表明该孕酮免疫生物传感器能有效的检测奶牛妊娠、发情和繁殖障碍疾病的乳汁孕酮水平。     

奶牛乳汁孕酮免疫检测的方法

孕酮(P4)是奶牛和黄牛在发情周期(一般为21天)中由卵巢黄体中产生的激素,可以进入血液、乳汁和唾液中。在母牛配种后21～24天期间采集奶测定孕酮浓度,可以判断牛是否受孕。发情期间奶中孕酮浓度可判断奶牛是否处于发情期。临床上,孕酮     

奶牛发情期前后脱脂乳中孕酮水平与受胎率之间的关系

本试验用酶联免疫法(EIA)对34头具有发情表现的上海黑白花奶牛进行了脱脂乳孕酮含量的测定.结果表明,配种后妊娠的母牛和未妊娠的母牛在原人工授精当天的脱脂乳孕酮水平分别为0.23±0.17ng/ml 和0.65±0.72ng/ml,两者差异显著(P<0.05).母牛在开始发情后16～18小时,脱脂乳孕酮水平低于0.23ng/ml 时配种,其受胎率为100%.     

银狐繁殖期血浆主要激素变化及其对繁殖功能的调控

通过放射免疫测定技术测定母银狐发情前期和发情期外周血浆雌二醇-17β[E2]、孕酮(P4)浓度以及公狐睾酮(T)浓度,并分析这些技术的变化及其对繁殖功能的调控.结果表明,银狐初配前2～3d,E2浓度达峰值(240.85±39.98)pg/mL,在母狐接受跨时E2浓度降至(146.95±38.21)pg/mL,而在发情前期和发情期,其孕酮浓度范围是0.91～77.43ng/mL,峰值是(54.77±23.66)ng/mL,在雌二酮峰值时,孕酮浓度为(28.57±21.21)ng/mL,配种时,P4浓度(33.12±22.56)ng/mL,初配后4d(排卵结束),P4达(48.28±34.84)ng/mL.公狐配种期,T浓度范围(127.2±444.4)pg/mL,,峰值是(341.2±103.2)pg/mL.     

如何解决好奶牛的流产问题

提高母牛的受胎率,首先要了解生殖器官及其功能,了解发情规律、掌握发情鉴定方法和妊娠鉴定方法,做好及时输精和正确的接产助产工作,使母牛按期生产,获得泌乳和产犊双丰收。1影响受胎率的因素影响奶牛受胎率的因素很多,包括精液晶质、母牛生殖道健康状况、奶牛饲料及营养状况、饲养管理情况、配种季节、气候环境因素和配种员的技术水平等。母牛发情周期正常范围18～25d的情期受胎率为61%,发情周期18d以下和25d以上的情期受胎率为46%。发情后12～36h排卵的情期受胎率为62%,发情后12h以内和36h以上排卵的情期受胎率为43％，前者比后者高19个百分点。     

甘加藏羊发情周期腺垂体和血浆中GTH含量动态变化

为了探讨甘加藏羊发情周期腺垂体和血浆中FSH和LH含量动态变化规律及排卵的关系。选取2.5~5岁,健康未孕雌性甘加藏羊30只,采集发情周期各阶段和乏情期腺垂体和血浆,采用酶联免疫吸附试验(ELISA)测定发情前期、发情期、发情后期、间情期及乏情期腺垂体和血浆中FSH和LH的含量。结果表明,甘加藏羊发情周期内腺垂体FSH浓度在发情期(6.873IU/L)和发情后期(6.863IU/L)较低,与间情期最大(8.228IU/L)差异显著(P<0.05),发情前期又降低(8.096IU/L);腺垂体LH浓度发情期(9.39IU/L)和发情后期(9.585IU/L)较低,间情期最大(10.629IU/L),发情前期(9.7325IU/L)降低,各时期差异不显著(P>0.05);发情周期内血浆中FSH浓度在发情前期(2.599IU/L)达到峰值,其他时期均较低,发情前期与其他时期差异显著(P<0.05);血浆LH浓度在发情期(3.866IU/L)达到峰值,发情后期(3.179IU/L)和间情期(3.292IU/L)降低,各时期差异不显著(P>0.05);并且FSH和LH在发情周期内均出现4个波峰:乏情期腺垂体和血浆中FSH和LH的浓度均低于发情周期内FSH和LH各自的基础值。FSH和LH含量在垂体和血浆的这些差异性应该是两者协同调控藏羊发情和排卵的主要原因。     

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.     

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.     

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.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

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