犬卵母细胞体外成熟的影响因素

采集发情期和间情期犬卵巢,回收大腔（直径大于１ｍｍ）卵泡和不可见卵泡的卵母细胞,在４种成熟液（ＴＣＭ１９９＋２０％ＦＣＳ,ＴＣＭ１９９＋２０％ＦＣＳ＋１０ＩＵ／ｍＬＦＳＨ,ＴＣＭ１９９＋２０％ＥＤＳ和ＴＣＭ１９９＋２０％ＥＤＳ＋１０ＩＵ／ｍＬＦＳＨ）中成熟后进行了受精试验。结果：（１）发情期大于２ｍｍ和１～２ｍｍ的大腔卵泡卵母细胞的体外成熟率（４２．５％,３２．５％）显著高于间情期卵母细胞（２０．４％）,但发情犬不可见卵泡卵母细胞的体外成熟率（２８．９％）与间情期卵母细胞差异不显著;（２）在成熟液中添加促性腺激素,能有效地提高卵母细胞成熟率,不可见卵泡的卵母细胞对促性腺激素的依赖性（３０．０％比７．８％）大于大腔卵泡的卵母细胞（４２．５％比２９．０％）;（３）卵丘扩散与卵母细胞成熟存在相关性;（４）ＥＤＳ可诱导卵丘扩散,但不能有效提高卵母细胞的成熟率;（５）发情期卵巢上的大腔卵泡和不可见卵泡的卵母细胞以及间情期卵巢不可见卵泡的卵母细胞体外培养后,与体外获能的精子进行体外受精,其卵裂率分别为１６．０％（４／２５）,０％（０／４０）和２．５％（１／４０）。     

牛体外受精胚胎细胞核移植的实验研究

将采自肉联厂屠宰车间的牛卵巢中的卵母细胞置于ＴＣＭ－１９９＋１０％ＥＣＳ（０ｄ）＋ＦＳＨ（１万ＩＵ／Ｌ）＋ＬＨ（５ｍｇ／Ｌ）中培养成熟，用含０．３％透明质酸酶的消化液将卵母细胞周围的卵丘细胞去掉，并以７．５ｍｇ／Ｌ的ＣＢ液处理后，用微吸管吸去透明带内的第一极体及极体下面的部分卵母细胞质，然后将经体外受精并发育至８～１６细胞期胚胎的卵裂球注入去核卵母细胞的卵周隙中，再将移核胚置于电融合槽内进行融合（电场强度为１２００Ｖ／ｃｍ，持续时间为８０μｓ，１次脉冲刺激）。将融合的胚胎移入生长有单层贴壁颗粒细胞的发育培养液（ＴＣＭ－１９９＋１０％牛血清）中培养，观察移核胚的融合率及发育率，部分去核卵母细胞经染色后观察去核率。结果表明：（１）移核胚的融合率为８６．９％（５３／６１）；（２）发育至２～８细胞期的胚胎占培养的移核胚胎总数的２１．３％（１０／４７）；（３）卵母细胞的去核率为６８．２％（４５／６６）。     

海狸鼠卵母细胞体外成熟培养初探

实验用ＰＭＳＧ或ＰＭＳＧ＋ＨＣＧ处理或未经激素处理的海狸鼠８只，共获卵巢卵母细胞１３８枚。激素处理对获取卵巢卵母细胞的数量没有影响，而对体外成熟发育至卵丘扩展和半成熟阶段有促进作用。三种不同培养液（Ｗｈｉｔｅｎ＋ＦＣＳ；ＴＣＭ１９９＋ＰＭＳＧ＋ＦＣＳ；ＴＣＭ１９９＋ＨＣＧ＋ＦＣＳ）共培养１２５枚卵母细胞，培养后卵丘扩展率及半成熟率分别为５６．５％，４５．７％，４７．６％和２１．７％，１２．３％，９．５％，以Ｗｈｉｔｅｎ液较高（分别为５６．５％和２１．７％），但只有ＴＣＭ１９９＋ＰＭＳＧ＋ＦＣＳ组有２枚卵母细胞出现第一极体。结果表明海狸鼠卵母细胞与其它啮齿动物的卵母细胞一样，能够在体外培养成熟，完成第一次减数分裂，排出第一极体     

猪核移植重组胚胎的发育能力

以ＭｃＧｒａｔｈ－Ｓｏｌｔｅｒ（１９８３）提供的去（注）核方法，将猪胚胎的单个卵裂球细胞注入去核的次级成熟卵母细胞，借助电融合的方法（ＡＣ；５Ｖ，１．５ＭＨｚ，１２－１５ｓ；ＤＣ：２ｋＶ／ｃｍ，４０μｓ。电激活／融合液：０．３ｍｏｌ／Ｌ甘露醇＋－．１ｍｍｏｌ／ＬＭｇＳＯ４＋０．１ｍｍｏｌＣａｃＬ２＋７．５ｍｇ／ｍｌＣＣＢ）融入受体胞质构成重级胚，体外培养（培养液为改衣ＴＣＭ－１９９；培养条件为５％     

BFF,rbGH对牛卵泡卵母细胞体外受精后发育的影响

利用屠宰黄牛卵巢，对２～５ｍｍ卵泡卵母细胞的体外成熟（ＩＶＭ）、体外受精（ＩＶＦ）、受精卵的体外培养（ＩＶＣ）进行了系列研究。结果表明，在成熟培养液中单独添加１０％Ｄ０ＥＣＳ（发情当天牛血清）获得了卵泡卵母细胞受精后较高的卵裂率（６４．７％）、桑椹胚发育率（３９．９％）和囊胚发育率（２４．８％），说明在成熟培养液中单独添加Ｄ０ＥＣＳ是可行的；在含１０％Ｄ０ＥＣＳ的成熟培养液中再添加１０％或２０％ＢＦＦ（牛卵泡液），均能提高受精卵的卵裂率以及桑椹胚和囊胚的发育率，以添加２０％ＢＦＦ效果较好，其囊胚发育率（３５．０％）显著高于对照组（２４．８％，Ｐ＜０．０５）；在卵泡卵母细胞成熟培养系统和受精卵共同培养系统中添加１０μｇ／Ｌ重组牛生长因子（ｒｂＧＨ），虽对体外受精卵的卵裂率无显著影响（Ｐ＞０．０５），但能显著提高卵裂胚的囊胚发育率（Ｐ＜０．０５）     

山羊卵巢无腔卵泡卵母细胞的体外生长

山羊卵巢无腔卵泡卵母细胞在以ＤＭＥＭ为基础,添加ＨＥＰＥＳ（２０ｍｍｏｌ／Ｌ）、ＦＣＳ（１０％）、ＦＳＨ（４０ｍｇ／Ｌ）、次黄嘌呤（２ｍｍｏｌ／Ｌ）、异双丁酰环腺苷酸（２ｍｍｏｌ／Ｌ）、ＩＧＦ－Ｉ（５０μｇ／Ｌ）、氢化可的松（４０μｇ／Ｌ）和ＩＴＳ（５０μｇ／Ｌ）的培养液中得以存活并生长。在二维培养体系中,卵泡在体外的生长模式和体内有很大差别。最显著的特征是卵泡不像在体内那样保持完整的立体结构一直到结束。绝大部分卵泡不同程度地发生基膜溶解和破裂,颗粒细胞向四周扩展并贴壁,形成单层。由于卵泡原有三维立体结构的破坏,易于导致卵母细胞的迁移。在生长方式上以数个卵泡聚集生长对其卵母细胞的生长似乎较为有利。卵泡卵母细胞在体外培养９ｄ,其直径可达１５０μｍ以上,达到了成熟时体积,存活率为５３％。实验证明,山羊无腔卵泡卵母细胞在合适的培养体系中,能在体外存活并生长,并能发育到成熟时的大小。     

鸡肝脏β—羟—β—甲戊二酸单酰辅酶A还原酶的提纯和性质

采用超速离心、热变性处理、硫酸铵沉淀和亲和层析方法，从鸡肝脏中分离提纯了β－羟－β－甲戊二酸单酰辅酶Ａ（ＨＭＧ－ＣｏＡ）还原酶。提纯倍数为２０９倍，比活力１８８．５Ｕ／ｍｇ，Ｋｍ值１．８×１０－４ｍｏｌ／Ｌ。ＳＤＳ－ＰＡＧＥ测得分子量为３．２×１０４。温度对该酶活性影响较大，３７℃时活性最高。最适反应ｐＨ为７．２。甘氨酸在１０ｍｍｏｌ／Ｌ浓度以上时对该酶呈现明显抑制作用，ｌ－组氨酸、ｌ－精氨酸则无明显抑制作用。Ｚｎ２＋、Ｍｇ２＋、Ｃｕ２＋离子对该酶有明显抑制作用，Ｚｎ２＋在１．５ｍｍｏｌ／Ｌ、Ｃｕ２＋和Ｍｇ２＋在２．０ｍｍｏｌ／Ｌ浓度以上时抑制作用明显。中药山楂（ＣＨＳ）和决明子（ＣＨＺ）的水煎液对酶的抑制作用明显     

红三叶组织培养及再生植株

本文采用ＭＳ，Ｂ５和ＰＣ一Ｌ２作为基本培养基，在不同激素组合条件下对红三叶（Ｔｒｉｆｏｌｉｕｍｐｒａｔｅｎｓｅ）子叶及下胚轴进行组织培养。在ＭＳ，Ｂ５和ＰＣ一Ｌ２附加２ｍｇ／Ｌ２，４－Ｄ和０．５ｍｇ／ＬＢＡ的培养基上，子叶及下胚轴愈伤组织诱导率均在８９％以上。愈伤组织继代在Ｂ５无机盐十三倍ＭＳ有机成分＋３％蔗糖＋０．５ｍｇ／Ｌ２，４－Ｄ＋０．５ｍｇ／Ｌ６ＢＡ０．２ｍｇ／ＬＮＡＡ，＋１０ｍｇ／ＬＶｃ的培养基上生长良好。愈伤组织在Ｂ５附加０．１ｍｇ／Ｌ６ＢＡ＋０．２ｍｇ／ＬＩＢＡ的培养基上再生植株。下胚轴在ＭＳ附加２ｍｇ／Ｌ６ＢＡ＋１ｍｇ／ＬＮＡＡ的培养基上直接分化形成丛生苗，转入无激素ＮＳ培养基上再生根。实验表明ＶＥ，Ｖｃ，ＰＶＰ和活性碳对愈伤组织褐化有抑制作用，１０ｍｇ／ＬＶｃ抗褐化作用最好。     

猪卵丘卵母细胞复合体和壁层颗粒细胞上LHR/hCGR的检测及性腺激素的分泌

用取自 ３～５ ｍ ｍ 卵泡的处于减数分裂阻抑状态的猪卵丘卵母细胞复合体（ｐ Ｃ Ｅ Ｏ），培养 ４８ ｈ，用 Ｆ Ｓ Ｈ（１００ Ｉ Ｕ／ Ｌ）或 ｈ Ｃ Ｇ（０、５０、１００、２００、５００ Ｉ Ｕ／ Ｌ）刺激 ｐ Ｃ Ｅ Ｏ 分泌甾体激素；用放射受体测定法（ Ｒ Ｒ Ａ）比较 ｐ Ｃ Ｅ Ｏ 的卵丘细胞及壁层颗粒细胞（ Ｍ Ｇ Ｃ）上促黄体激素受体／人绒毛膜促性腺激素受体（ Ｌ Ｈ Ｒ／ｈ Ｃ Ｇ Ｒ）的数量； Ａ Ｍ ｅ Ｘ 石蜡切片、免疫组织化学染色，检测 Ｌ Ｈ Ｒ／ｈ Ｃ Ｇ Ｒ 在 ｐ Ｃ Ｅ Ｏ 以及 Ｍ Ｇ Ｃ 的分布情况。在 Ｆ Ｓ Ｈ 作用下，ｐ Ｃ Ｅ Ｏ 分泌的孕酮明显高于 ｈ Ｃ Ｇ 作用组和对照组 （ Ｐ ＜ ００５）； 平均每个壁层颗粒细胞上的 Ｌ Ｈ Ｒ／ｈ Ｃ Ｇ Ｒ是每个卵丘细胞的 １０５ 倍； Ｌ Ｈ Ｒ／ｈ Ｃ Ｇ Ｒ 在基膜两侧分布较多，且卵母细胞上没有 Ｌ Ｈ Ｒ／ｈ Ｃ Ｇ Ｒ，临近卵母细胞的卵丘细胞膜上较少被染色。以上结果表明，在体外试验中，可能由于 Ｃ Ｅ Ｏ 上 Ｌ Ｈ Ｒ／ｈ Ｃ Ｇ Ｒ 的数量不足或生理活性降低， Ｌ Ｈ／ｈ Ｃ Ｇ 不能促进卵母细胞恢复减数分裂。     

混合保护液和冻前处理方法对小鼠胚胎一步冷冻效果的影响

选用Ａ￣Ｅ５种混合保护液：Ａ．二甲亚砜（ＤＭＳＯ）＋乙醇（ＥＧ），Ｂ．甘油（ＧＬ）＋丙二醇（ＰＧ），Ｃ．ＧＬ＋ＥＧ，Ｄ．ＧＬ＋ＤＭＳＯ，Ｅ．ＰＧ＋ＥＦ，以２种冻前处理方法，对小鼠桑椹胚和囊胚进行一步冷冻，冷冻混合保护液中各种保护剂浓度均为２５％。法的冻前平衡液为ＶＳ２的对倍稀释液；法的冻前平衡液中，前一种保护剂浓度为１０％，后一种保护剂浓度为２０％。胚胎于室温（２０℃）下在ＶＳ１中平衡５ｍｉｎ或Ｖ     

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 -