促卵泡激素和胰岛素对牛卵泡颗粒细胞长期培养的影响

以McCoy’s5a为基础培养液添加硒、转铁蛋白、雄烯二酮、谷氨酰胺，对牛卵巢上大（直径〉8mm）、中（4mm〈直径〈8mm）、小（直径〈4mm）非闭锁卵泡的颗粒细胞进行无血清培养，研究添加不同浓度的促卵泡激素（FSH）和胰岛素对颗粒细胞增生、分化和激素分泌的影响。结果，FSH能诱导颗粒细胞增生及提高其雌二醇合成能力，颗粒细胞雌二醇的合成能力与生理浓度的FSH存在剂量依赖关系。胰岛素对大、中、小卵泡颗粒细胞增生和雌激素分泌有促进作用。     

牛卵泡颗粒细胞无血清培养的形态学观察

McCoy’s5a为基础培养液添加硒、转铁蛋白、雄烯二酮、谷氨酰胺 ,对牛卵巢上大 (直径 >8mm)、中 ( 4mm <直径 <8mm)、小 (直径 <4mm)非闭锁卵泡的颗粒细胞进行无血清培养。McCoy’s5a无血清培养中的颗粒细胞形态与分化特点类似于体内情况 ,说明颗粒细胞在该培养条件下 ,其功能可能更接近体内的生理状况     

FSH、LH对体外培养的牦牛卵泡颗粒细胞凋亡及E_2、P分泌功能的影响

为了探明促卵泡素(Follicle stimulating hormone,FSH)和促黄体素(Luteinizing hormone,LH)对体外培养的牦牛卵泡颗粒细胞凋亡及甾体激素分泌的影响,揭示促性腺激素调控卵泡发育的机理,采用细胞培养和显微观察技术,建立了牦牛卵泡颗粒细胞体外培养体系,观察分析牦牛卵泡颗粒细胞体外培养的生长特征和凋亡的形态特征;采用流式细胞技术(Flow cytometry,FCM)和放射免疫测定技术(Radioimmunoassay,RIA),分析了添加不同浓度的FSH和LH对牦牛卵泡颗粒细胞凋亡和雌二醇(Estradiol,E2)、孕酮(Progesterone,P)分泌的影响。结果显示,体外培养的牦牛卵泡颗粒细胞呈现出典型的上皮样细胞生长特性,具有典型的"S"形生长曲线,体外培养的牦牛颗粒细胞偶尔可见细胞核浓缩、边集化、染色质固缩、内质网疏松等凋亡的形态特征。在添加0.050~5.000IU·mL-1FSH,随着浓度的增加,凋亡细胞比例逐渐降低,E2和P水平呈上升趋势;在添加浓度达到5.000IU·mL-1时,凋亡细胞比例最低降到7.3%,与对照组差异极显著(P0.01)。低浓度的LH(0.050~0.500IU·mL-1),可以抑制颗粒细胞凋亡,促使E2和P分泌增加;高浓度的LH(5.000IU·mL-1)则促使颗粒细胞凋亡,对颗粒细胞分泌E2和P的影响不明显。这一结果表明,FSH和LH可通过调节牦牛颗粒细胞的凋亡及分泌功能,在调控卵泡发育及排卵的过程中发挥重要作用。     

牛卵巢卵泡Smad9表达模式的研究

本研究旨在探究Smad9在牛卵巢卵泡中的表达模式,为研究Smad9的功能奠定基础。从屠宰场获取牛卵巢,分离得到小卵泡(2 mm≤直径≤4 mm)、中卵泡(4 mm直径8 mm)、大卵泡(直径≥8 mm),用免疫组织化学技术对不同直径卵泡的Smad9蛋白进行定位分析;通过机械分离法分离卵泡颗粒细胞,用qPCR和Westernblotting技术检测Smad9在小卵泡、中卵泡、大卵泡颗粒细胞中的相对表达量。结果显示:在牛的卵泡中,Smad9在颗粒细胞和膜细胞层中表达;小卵泡和中卵泡颗粒细胞中Smad9mRNA转录本相对丰度低于大卵泡颗粒细胞(P0.01),而中卵泡颗粒细胞内Smad9 mRNA转录本相对丰度低于小卵泡(P0.05);中卵泡和小卵泡颗粒细胞中Smad9蛋白的表达量低于大卵泡(P0.01),中卵泡颗粒细胞中Smad9蛋白表达量是小卵泡的0.9倍(P0.05)。综上,Smad9主要在牛卵泡颗粒细胞层中表达,且大卵泡表达量极显著高于小卵泡和中卵泡。     

鹅就巢期卵巢特征及其内分泌机制的研究进展

鹅的就巢行为显著影响其产蛋量,就巢行为主要受下丘脑-垂体-性腺轴(HPG)分泌的相关激素调控。相关激素主要包括促性腺激素释放激素(GnRH)、催乳素(PRL)、促卵泡激素(FSH)、促黄体素(LH)、雌二醇(E_2)和孕酮(P_4),共同调控鹅的就巢行为。在就巢期,机体内PRL分泌浓度升高,能够抑制GnRH和FSH的分泌,导致大卵泡合成P_4、E_2速率下降,从而垂体分泌LH浓度降低。本文对鹅就巢期激素水平及卵巢形态变化进行阐述,以期通过调控鹅就巢行为来提高产蛋量的相关研究提供理论支持。     

添加外源激素FSH对绵羊卵丘颗粒细胞增殖的影响

为了分析外源激素促卵泡激素(FSH)对绵羊卵丘颗粒细胞增殖的影响,试验分离并体外培养了绵羊卵丘颗粒细胞,然后使用促卵泡激素受体(FSHR)免疫组织化学法鉴定了分离培养的细胞,进而分析了添加不同浓度FSH对细胞增殖速度的影响。结果表明:将卵丘颗粒细胞从卵丘颗粒细胞-卵母细胞复合体(COCs)上分离24 h之后,能够观察到部分卵丘颗粒细胞开始贴壁,传代之后细胞形态未发生明显变化。FSHR免疫组织化学法鉴定结果证明分离培养的绵羊卵丘颗粒细胞能够特异性地表达FSHR。培养基中添加FSH后,在培养前4 d,高浓度(100 ng/mL)和低浓度(10 ng/mL)的FSH均能促进卵丘颗粒细胞的增殖,但在培养6 d之后,高浓度的FSH对卵丘颗粒细胞的增殖存在抑制作用。说明外源激素FSH在不同浓度下对卵母颗粒细胞的增殖具有不同的影响。     

绵羊卵泡期卵泡颗粒细胞FSHR差异剪接体的表达

为探讨卵泡期卵泡颗粒细胞促卵泡素特异性受体(FSHR)差异剪接体表达的变化,选择30只道寒杂交一代育成母羊肌注PG+埋植CIDR+肌注PG进行同期发情处理,选取9只发情母羊屠宰,取两侧卵巢组织,按小卵泡(≤3.0 mm),中等卵泡(3.0～5.0 mm)和大卵泡(≥5.0 mm)级别分别收集卵泡液和颗粒细胞,采用放射性免疫法测定类固醇激素(E_2和P_4)和FSH浓度,实时定量PCR检测不同直径卵泡颗粒细胞FSHR差异剪接体表达水平。结果表明,小卵泡和中等卵泡中FSHR1和FSHR3 mRNA的表达量极显著高于FSHR2和FSHR4(P0.01),在中等卵泡中FSHR3 mRNA的表达量显著高于FSHR1(P0.01);大卵泡中FSHR2 mRNA的表达量显著高于FSHR1、FSHR3和FSHR4(P0.01),FSHR1、FSHR3和FSHR4 mRNA的表达量差异不显著(P0.05)。大卵泡中雌激素浓度极显著高于小卵泡和中等卵泡(P0.01),孕酮浓度无显著性差异(P0.05),E_2/P_4比值与大卵泡中FSHR3 mRNA的表达量呈极显著负相关(P0.01)。由结果可知,卵泡发育过程中FSHR1和FSHR3可能是小卵泡和中等卵泡颗粒细胞增殖的2种主要剪接形式。     

促性腺激素(FSH、LH)对牛腔前卵泡体外发育及E_2分泌的影响

利用McCoy's 5a基础无血清培养系统研究了促卵泡素(FSH)、促黄体素(LH)2种促性腺激素对牛腔前卵泡的体外生长、存活及雌二醇(E2)分泌的影响.结果显示,培养液中单独添加LH对牛腔前卵泡生长影响不大,而单独添加50、100μg/L以上FSH对牛腔前卵泡直径增长和培养后期体外存活有明显的促进作用;当培养液中有10 μg/L LH存在时,2种促性腺激素协同刺激卵泡生长的作用更加明显.添加10 μg/L LH 50μg/L FSH对腔前卵泡体外生长、发育、存活及E2分泌均具有显著的促进作用(P<0.05).     

牛卵泡颗粒细胞无血清培养的形态学观察

以McCoy＇s 5a为基础培养液添加硒、转铁蛋白、雄烯二酮、谷氨酰胺，对牛卵巢上大（直径＞8mm）、中（4mm＜直径＜8mm）、小（直径＜4mm）非闭销卵泡的颗粒细胞进行无血清培养。结果表明，McCoy＇s 5a无血清培养中的颗粒细胞形态与分化特点类似于体内情况，说明颗粒细胞在该培养条件下，其功能可能更接近体内的生理状况。     

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.     

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