高寒放牧条件下牦牛超排试验

在高寒放牧条件下,对12头祁连山型母牦牛进行了选择不同超排方法和FSH剂量及使用中科院动物所FSH、LH,国产PGP2α、HCG,新西兰FSH的超排试验,供试母牦牛在发情11～12天开始注射FSH.结果表明A组FSH 8.4 mg,母牦牛与正常发育相似,冲出2枚发育正常囊胚,1头放弃;B组FSH 8.6 mg,利用PVP包埋1次注射,母牦牛卵巢处于静止状况,插管1头,没有冲出胚胎,超排处理无结果.说明牦牛用FSH 8.4～8.6mg剂量偏小,对超排无效果;C组FSH8.8 mg,分FSH+LH(2001U)、FSH+HCG(10001U)、卵巢黄体数10±4,2头牦牛冲卵,获14枚胚胎,有1头牦牛冲出10枚胚胎,其中有2枚发育到16细胞,1枚发育到32细胞,说明FSH+HCG(LH)有协同作用,促进卵巢上卵母细胞成熟和排卵;D组FSH 15 mg(新西兰产)1头牦牛冲出3枚发育正常早期囊胚.     

西藏当雄牦牛超数排卵及胚胎移植试验

2005年8月初，对西藏当雄10头5~10岁供体母牦牛实施了超数排卵试验，超排选用PGF2α+FSH刺激法和埋置阴道栓Cu-Mate⁺促卵泡素FSH刺激法，FSH的剂量为8.8~9.0 mg/头。根据超排后供体发情表现、黄体数量及获得胚胎数量及质量评定超排效果，将胚胎鲜胚移植给经同期处理的受体母牦牛。结果为：10头供体牛共获得7枚胚胎，PGF2α+FSH连续递减法得到5枚可用胚胎，Cu-Mate+FSH法没有冲到胚胎，５枚胚胎移植给５头受体后妊娠并出生４头牦犊牛。结论为：PGF2α+FSH连续递减法超排效果较好，胚胎移植取得初步成功。     

青藏高原牦牛超数排卵试验

在高原放牧条件下,对6头环湖型牦牛进行了不同外源激素组合处理的超数排卵试验.结果表明:试验A组(FSH PG HCG)和试验B组(FSH PG)供体牛对国产激素超排处理都有反应.试验A组获黄体数超过20个,回收胚胎14枚,其中可用胚胎11枚,4～16细胞胚胎3枚;试验B组获黄体数20个,回收1枚可用胚胎,为B级囊胚.     

肉用黑萨福克绵羊超数排卵和配种授精方案的优化

本研究旨在优化肉用黑萨福克绵羊超排方案,筛选生产条件下最佳配种授精方式,提高黑萨福克体内胚胎生产效率,建立高效绵羊胚胎移植体系。供体超数排卵采用不同超排方案、不同FSH剂量、不同配种授精方式、不同侧卵巢超排效果、不同季节以及重复利用6组因素的比较试验。结果表明:采用CIDR+FSH+PMSG递减4d 8针注射法供体平均黄体数16.00个/只、可用胚数14.00枚/只和移植妊娠率71.43%,效果最好(P<0.05);FSH注射剂量范围在200²60 IU,超排平均黄体数、平均可用胚胎数分别为14.87、13.28枚/只,高于160260 IU,超排平均黄体数、平均可用胚胎数分别为14.87、13.28枚/只,高于160²00 IU组和260200 IU组和260³20 IU组(P<0.05);开膣器输精+自然交配+开膣器输精方法供体冲出卵子的受精率97.32%、平均可用胚数11.25枚/只,高于其他2种配种方式(P<0.05);不同侧卵巢超排效果无差别;繁殖季节(秋季)供体平均黄体数13.00个/只、可用胚10.75枚/只,高于非繁殖季节(P<0.05);重复超排效果无明显差异。本研究获得了黑萨福克绵羊超数排卵的技术参数,优化了黑萨福克绵羊超排方法和配种授精方案,建立了高效的胚胎移植体系。     

不同剂量促卵泡素对超排效果的影响

用两种不同剂量的FSH进行超排处理 ,结果表明 ,用 9mg的FSH处理 ,头均获得胚胎 6 2枚、可用胚 3 8枚 ;分别比 8mg处理组多 3 4枚、1 8枚 (P <0 0 5 )。表明用 9mgFSH进行超排处理效果较好。     

海门山羊超数排卵,卵巢反应和胚胎发育观察

用促性腺激素 FSH(280IU 和340IU)、PMSG(1000IU)对海门山羊进行超数排卵处理,并比较它们的超排效果.试验结果表明:用280IU 的 FSH 超排,排卵数平均为7.5±4.6;用340IU 的 FSH 超排,排卵数平均为8.6±6.2;用 PMSG 超排,排卵数平均为5.5.FSH 处理超排效果比 PMSG 处理效果好。FSH 组的两种剂量间的效果差异不显著(P>0.05);卵巢对激素的反应比较明显,卵泡多,卵巢体积增大.经观察,胚胎发育在发情配种后的第3天,以单细胞受精卵到2细胞阶段的胚胎趋多;第4天,以4—8细胞阶段的胚胎趋多;第5天,以16—32细胞阶段趋多;第6天,发育到桑椹胚;第7—8天,以囊胚趋多。这一结果,为海门山羊今后进行胚胎工程提供了参考价值。     

促卵泡素超排效果比较试验

用宁波产促卵泡素(FSH)超排处理供体牛19头,共冲出156枚卵,每头平均8.21枚,其中可用胚胎为140枚,每头平均7.36枚,达到国内平均水平;用北京产FSH超排处理供体牛15头,共冲出98枚卵,每头平均6.53枚,其中可用胚胎为72枚,每头平均4.48枚.试验证明2个不同产地FSH的超排效果有显著差异.     

皖江长毛兔超数排卵及胚胎移植研究

采用国产激素,以FSH LH、FSH HCG、PMSG LH、PMSG HCG4种不同的处理方法对32只皖江长毛兔进行了超排处理,旨在筛选确定皖江长毛兔最有效的超排方法及胚胎移植的最佳时期。结果表明:4种超排方法处理后的排卵数分别为42.5枚、46.25枚、30.63枚、33.38枚;回收胚胎数分别为27.63枚、31.25枚、22.37枚、20.75枚;有效胚胎数分别为20.50枚、24.13枚、17.63枚、15.25枚。这三项指标均以FSH HCG组最高。将收集到的237枚胚胎移植给24只受体,每只受体移植胚胎10枚左右。结果表明:2、4、8~16细胞期及桑椹胚移植后的妊娠率、产仔率及窝产活仔数分别为50%、16.6%和3.3只,66.7%、20.6%和3只,60%、24.5%和4.3只,71%、40.9%和5.4只。其中以桑椹胚组指标最高。     

超排方法及兔龄对家兔超排效果的影响

采用国产促卵泡激素（FSH），促黄体激素（LH）和人绒毛膜促性腺激素（HCG），分别以FSH LH（A法），FSH HCG（B法）两种不同的处理方法，对不同年龄的家兔进行超排处理，旨在选择对家兔有效的超排方法，比较兔龄对超排效果的影响。结果表明，用A法对经产母兔和青年母兔处理后的排卵数分别为68枚，46枚；回收胚胎数分别为36枚，15枚；有效胚胎数分别为27枚，10枚，用B法对经产母兔和青年母兔处理后的排卵数分别为93枚，71枚；回收胚胎数分别为59枚，37枚，有效胚胎数分别为45枚。26枚。以上指标均以FSH HCG组最高，经产兔超排效果较青年兔好。     

屡配不孕荷斯坦母牛超数排卵的试验

用加拿大生产的FSH对屡配不孕荷斯坦母进行超数排卵处理,取得良好的超排效果。处理5头,共冲出30枚卵,每头平均6枚,其中可用胚胎为21枚,每头平均4．2枚。     

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 -