Cumulus Oophorus Expansion of Bovine Oocytes Cultured in vitro: A SEM and TEM Study

Bovine cumulus-oocyte complexes (COCs) were aspirated from antral follicles (3–6 mm in diameter). COCs with a compact multilayered cumulus investment were cultured for 9, 13 and 24 hours, respectively, and processed for scanning or transmission electron microscopy after different periods of culture including a 0 hour control group. In all 0 hour control COCs initial formation of cumulus cell projections, blebs and microvilli were observed. The start of cumulus-oocyte disconnection in cattle was observed after 9 hours of in vitro culture. These connections were almost completely discrupted after 13 hours, when a continuous production of extracellular matrix was observed. The full expansion of corona radiata cells was not observed even after 24 hours. Some cumulus oophorus cells were bound together with junctions of the zonula adherens type after 24 hours when extracellular matrix was found only in deeper layers. The full expansion of corona radiata cells was not the prerequisite for disconnection of cumulus-oocyte complex. Inhalt: Kumulus oophorus Expansion von in vitro kultivierten Rinderoozyten: Eine SEM und TEM Untersuchung Kumulus-Oozyten-Komplexe (COC) von Rindern wurden aus antralen Follikeln aspiriert (Durchmesser 3–6 mm). COC's mit kompakten mehrschichtigen Kumulus wurden für 9, 13 und 24 Stunden kultiviert und für die Scanner- oder Transmissionselektronenmikroskopie vorbereitet. Verschiedene Kulturzeiten incl. einer 0-Stundengruppe als Kontrolle wurden untersucht. In allen Kontroll COC's wurden beginnende Formationen yon Kumuluszellprojektionen, Bläschen und Mikrovilli beobachtet. Nach 9-stündiger in vitro Kultur begann die Lösung zwischen Kumulus und Oozyte. Die Verbindungen waren nach 13 Stunden vollständig unterbrochen, wobei eine kontinuierliche Produktion extrazellulärer Matrix beobachtet wurde. Eine vollständige Expansion der Corona radiata Zellen wurde auch nicht nach 24 Stunden beobachtet. Nach 24 Stunden waren einige Cumulus Oophorus Zellen über Verbindungen des Zonula adherens Typs verknüpft, wobei extrazelluläre Matrix nur in den tieferen Zellschichten gefunden wurde. Eine vollständige Kumulusexpansion ist keine Voraussetzung für die Auflösung des Kumulus-Oozyten-Komplexes.     

血清对水牛卵母细胞体外成熟、体外受精及早期胚胎发育的影响

从屠宰场收集了本地水牛55头、黑白花奶牛22头的卵巢共获卵泡847枚,平均每个水牛卵巢回收3.67枚可用卵母细胞,约为黑白花奶牛(10.23枚/头)的1/3。试验分别采用添加与不添加血清的培养液体外成熟培养水牛卵母细胞,结果二者的成熟率无明显毒性差异(58.23%对56.67%),但体外受精后早期胚胎发育的8-细胞率有显著差异(35.4%对23.0%),表明体外成熟液中有无血清对水牛卵母细胞体外成熟率没有影响,但血清对卵母细胞的早期胚胎发育有重要影响。进一步比较成熟液中不添加血清但在受精液及胚胎液中添加血清和在各个阶段均有血清参与的早期胚胎发育率(8-细胞率),表明二者差异不显著(33.8%对35.4%)。经无血清成熟培养液培养的成熟卵母细胞可以经孤雌激活后得到早期胚胎(4细胞)。     

Mange in pigs: A survey

Extract

Mange in pigs caused by Sarcoptes scabiei var. suis is reported to be common in New Zealand, but, to the writer's knowledge, no investigation has been made of the number of infested farms in any area.     

牛副结核检疫中的非特异性干扰

给犊牛接种各种分枝杆菌，然后以副结核ＰＰＤ进行变态反应试验，观察各分枝杆菌感染对副结核变态反应的干扰；从各种分枝杆菌感染牛群采取血清进行副结核ＥＬＩＳＡ检测，以观察各分枝杆菌血清对牛副结核ＥＬＩＳＡ的干扰。结果：多种分枝杆菌，特别是鸟胞内分枝杆菌、瘰疬分枝杆菌的感染可干扰副结核变态反应；部分结核牛血清干扰副结核ＥＬＩＳＡ的检测     

Effect of Psammaplin A on in vitro Development of Bovine Aging Oocytes

To investigate the effect of histone deacetylation inhibitor Psammaplin A (PsA) on the development of bovine aging oocytes in vitro,oocytes were randomly divided into control group,aging group and 50 mmol/L PsA treated aging group (PsA group).Immunofluorescence staining and JC-1 were used to detect the blastocyst rate of bovine oocytes after parthenogenetic activation,the number of cells in blastocysts,apoptosis,reactive oxygen species (ROS),glutathione (GSH) and mitochondrial membrane potential intensity of embryos.The results showed that the blastocyst rate of the aging group was significantly lower than that of PsA and control groups (P<0.05).The blastocyst rate of PsA group was not significantly different from that of control group (P>0.05).The number of cells in the blastocysts of control group and PsA group were significantly higher than that of aging group (P<0.05).The number of cells in the blastocysts of PsA group was not significantly different from that of control group (P>0.05).The apoptosis rate in aging group was significantly higher than that of control and PsA groups (P<0.05),the apoptosis rate of PsA group was significantly higher than that of control group (P<0.05).The GSH level of MⅡ oocytes in aging group was significantly lower than that of control and PsA groups (P<0.05).There was no significant difference in GSH level between control and PsA groups (P>0.05).The ROS level of the embryos in aging group was significantly higher than that of control and PsA groups (P<0.05).The ROS level in PsA group was significantly higher than that of control group (P<0.05).The mitochondrial membrane potential of early embryos of aging group 4-8 cells was significantly lower than that of control and PsA groups (P<0.05).The mitochondrial membrane potential intensity of control group was significantly higher than that of PsA group (P<0.05).In summary,PsA could effectively delay the aging of bovine oocytes and improve the quality of oocytes.     

转基因牛多重PCR检测方法的建立

为建立一种快速检测转基因牛的多重PCR方法,针对牛线粒体16 S rRNA基因(BOS mtD-NA16 S rRNA,BOS)、转基因动物常用标记基因新霉素磷酸转移酶基因(NPT Ⅱ)、人乳铁蛋白编码基因(human laetoferrin gene,hLF)、人-α-乳清蛋白编码基因(human α-lactalb...     

牛胃肠炎发生原因及防治

胃肠炎是家畜生长中的常见病和高发病,牛具有很高的发病率。造成胃肠炎发生的原因是饲养管理不到位、饲料营养价值较差,饲料不足,牛出现营养不良,身体抵抗能力下降,使消化机能变差,进入消化道中的饲料不能很好的吸收,肠鸣音大,饲料随着肠道的蠕动排出体外。临床上主要表现为腹泻、身体脱水、生长发育不良。由于牛胃肠炎的发生机理还不明确,病因比较复杂,在疾病诊治期间应尝试明确实际的发病愿意,对动物进行对症防治,确保牛健康生长。该文主要论述牛胃肠炎的发生原因和防治措施。     

Prevalence of Mycobacterium avium subspecies paratuberculosis (MAP) infection in suspected diarrhoeic buffaloes and cattle reporting at Veterinary University in India

Murrah buffaloes, best breed for milk production are native of Haryana state. They contributes significantly to the farmer’s income, livelihood and food (milk and meat) security, in the semi-tropical regions of North India. Johne’s disease though endemic in the domestic livestock of the country, but reports are not available in the buffaloes suffering from morbidity due to progressive weakness and diarrhoea. We estimated the status of JD in diarrhoeic buffaloes and cattle reporting at Veterinary Clinical Complex of Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana, India, using conventional, serological and PCR assays.141 buffaloes suffering from chronic diarrhoea were screened to estimate sero-prevalence of MAP and 50.0 % young and 53.52 % adult animals were positive. Of 14 cattle screened, none of the young and 66.6 % adult cows were positive. In buffaloes, 66.1 and 6.77 %, fecal samples were positive in microscopy and IS900 PCR, respectively. Sero-prevalence of JD was very high in diarrhoeic buffaloes and cattle from Haryana state of India.Buffaloes positive for Mycobacterium avium subspecies paratuberculosis (MAP) infection had reduced total leukocyte count and lymphocytes.     

Reestablishment of transzonal projections and growth of bovine oocytes in vitro

Transzonal projections (TZPs) that maintain bidirectional communication between oocytes and granulosa cells or cumulus cells are important structures for oocyte growth. However, whether TZPs develop between TZP-free oocytes and granulosa cells, and whether reestablished TZPs support oocyte growth, is unknown. We first examined changes in TZPs after denudation of bovine oocytes collected from early antral follicles (0.5–0.7 mm). Twenty-four hours after denudation, almost all the TZPs disappeared. We also examined the reestablishment of TZPs by coculturing TZP-free denuded oocytes (DOs) with mural granulosa cells (MGCs) collected from early antral follicles. In addition, to confirm if the reestablished TZPs were functional, the reconstructed complexes (DO+MGCs) were subjected to in vitro growth culture and found that the MGCs adhered to TZP-free DOs and TZPs were reestablished. During in vitro growth culture, DO+MGCs developed and formed antrum-like structures. After culture, the number of TZPs in DO+MGCs increased, and the oocytes grew fully and acquired meiotic competence. These results suggest that reestablished TZPs are able to support oocyte growth.     

Reduced protein kinase C activity and endogenous protein phosphorylation in ethionine-induced fatty liver in cows

Protein kinase C (PKC) activity was evaluated and the phosphorylation of its endogenous substrates was explored in fatty liver induced by administration of ethionine (an analogue of methionine) to cows in order to assess the relevance of PKC-dependent phosphorylation in the development of fatty liver. PKC activity was decreased in both the cytosolic and the total particulate fractions from fatty livers, compared to the corresponding fractions from control liver. The mode of activation by the PKC cofactors (1-oleoyl-2-acetyl-sn-glycerol, 12-O-tetradecanoylphorbol-13-acetate, phosphatidylserine and Ca²⁺) was similar in both control and fatty livers, suggesting a quantitative but not a qualitative change in PKC in fatty liver. At least three substrate proteins (34 kDa, 26 kDa and 19 kDa) were found in the cytosolic fraction and their phosphorylation was reduced in fatty liver. These results suggest that impairment of the signal transduction pathway mediated by PKC is involved in the pathogenesis of fatty liver in cows.Abbreviations ATP adenosine triphosphate - EGTA ethylene glycol bis(-aminoethylether)-N,N,N,N-tetraacetic acid - NEFA non-esterified fatty acid - OAG 1-oleoyl-2-acetyl-sn-glycerol - PKC protein kinase C - PS phosphatidylserine - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis - TG triglyceride - TPA 12-O-tetradecanoylphorbol-13-acetate