Leukotrienes Affect Secretory Function of Ovarian Cells In Vitro*

The aim of this study was to determine which cells are the source of production and target for leukotriene (LTs) action within the bovine ovary. Luteal (CL, days 14–16 of the oestrous cycle), steroidogenic cells (LSC) and endothelial cells (LEC) of the bovine corpus luteum (CL), and granulosa cells (GC) were isolated enzymatically, cultured in a monolayer and incubated with LTC₄, LTB₄, Azelastine (an antagonist of LTC₄) or Dapsone (an antagonist of LTB₄). Then cells were collected for determination of mRNA expression for LT receptors (LTRs) and 5‐lipoxygenase (5‐LO) by real time RT‐PCR, and media were collected for determination of prostaglandin (PG)E₂, F_2α, progesterone (P4; LSC only), endothelin‐1 (ET‐1; LEC only) and 17‐β oestradiol (E2; GC only). The greatest mRNA expression for LTR‐II and 5‐LO were found in LEC, whereas LTR‐I mRNA expression did not differ among cell types. The level of PGE₂ increased after LTs treatment in each type of ovarian cell, excluding LTC₄ treatment in LEC. The secretion of PGF_2α was also increased by LTs, but decreased after LTB₄ treatment of LSC. In GC cultures, both LTs stimulated E2 secretion; in LEC cultures, LTB₄ stimulated whereas LTC₄ inhibited P4 secretion; in LEC cultures, LTC₄ stimulated but LTB₄ inhibited ET‐1 secretion. The results show that LTs are produced locally and are involved in PGs production/secretion in all examined cells (LSC, LEC and GC) of bovine ovary. Leukotriene treatment modulate secretion of E2, by GC, P4 by LSC and ET‐1 by LEC, which indicates that LTs are involved in regulation of ovarian secretory functions.     

Prevalence and distribution of Trypanosoma evansi in camels in Somaliland

Tropical Animal Health and Production - The prevalence and distribution of Trypanosoma evansi (T. evansi) infection on camels in Somaliland were studied using the card agglutination test (CATT/T....     

Pyometra and unilateral uterine horn torsion in a sheep

A 13‐year‐old Romanov sheep presented for evaluation of vaginal discharge, depression and anorexia. Blood work demonstrated mature neutrophilia and marked hyperlactatemia. Transrectal and transabdominal ultrasound revealed echogenic fluid (pus) within the uterus. Purulent uterine fluid culture yield Escherichia coli. A diagnosis of pyometra was made. After medical treatment without clinical improvement, an exploratory laparotomy was performed, and a 360‐degree uterine left horn torsion was identified with the pyometra and multiple corpora lutea on both ovaries. Ovariohysterectomy was performed and the ewe recovered uneventfully.     

Forms of Reproductive Disorders in Cattle and Buffaloes in Middle Egypt

The objective of this study was to investigate the common forms of reproductive disorders and trends of fertility in cattle and buffaloes in Middle Egypt, and investigate nutritional deficiencies or imbalances as a cause of infertility. During the period from 2003 to 2006 a total of 4276 animals (2755 cattle and 1521 buffaloes) were examined, during winter and summer at three districts of Middle Egypt. Based on the owner complains, animals were categorized as anestrum, repeat breeder and those for pregnancy diagnosis. Feedstuffs of these districts were assessed for nutrient and mineral contents. Animals were examined by rectal palpation and by transrectal ultrasonography. The results showed that, ovarian inactivity was the most common cause of anestrum, whereas endometritis was the main frequent finding of repeat breeding. District, season and year affected the incidences of infertility. The pregnancy rate remained constant (cattle) or increased (buffaloes) from 2003 to 2006. The incidence of ovarian inactivity in both species decreased over the same period. In winter, the commonly used feedstuffs would be adequate to supply the animals with needs, but in summer, rations seem to be deficient in many essential nutrients. In conclusion, ovarian inactivity is the main cause of infertility in cattle and buffaloes in Middle Egypt. There is a link between poor nutrition in summer and the high incidence of ovarian inactivity. Fertility trends during the past few years are encouraging.     

关于澳洲坚果主要推广品种的建议

为了筛选出适合我国种植的澳洲坚果品种,对我国澳洲坚果主产区9个主要品种的产量和品质进行分析。结合澳洲坚果产业的健康发展,建议我国目前的澳洲坚果主要推广品种使用桂热5号(Own choice)和桂热6号(900#),在广西、广东和攀枝花等地的辅助品种可使用桂热7号(695#)和桂热8号(788#)等,在云南辅助品种可使用桂热7号(695#)、桂热8号(788#)、344#、660#和741#等。     

华北落叶松鞘蛾性信息素应用技术研究

1999年至2000年,山西省太岳山林局应用人工合成的华北落叶松鞘蛾性信息素对华北落叶松鞘蛾进行了监测,并开展了大量诱杀试验。结果表明,该引诱剂对华北落叶松鞘蛾雄蛾有较强的引诱作用,60个诱捕器在成虫扬飞期共诱到鞘蛾成虫51万头,应用诱捕器后,林地内华北落叶松鞘蛾被害率下降50.1％,虫口密度下降81.2％。可用于对华北落叶松鞘蛾的监测和防治。