Follicular dynamics throughout the oestrous cycle in sheep. A review
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چکیده
منابع مشابه
Follicular dynamics throughout the oestrous cycle in sheep. A review.
Whatever the stage of the cycle, follicles of various sizes are apparent on the surface of the ovary of sheep. No evidence of waves of follicular growth at fixed-time intervals has been found during the luteal phase, and growth probably occurs at random until the follicle attains a size of 4 to 7 mm. This shows that follicles can enlarge under a wide range of hormonal levels. The recruitment of...
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Gonadotropins are protein hormones secreted by the pituitary gland and include luteinizing hormone (LH) and follicle stimulating hormone (FSH). Both LH and FSH govern the estrous cycle i.e. the cyclical pattern of ovarian activity that facilitates the transition of female animals between periods of reproductive non-receptivity to receptivity enabling mating and subsequent pregnancy. The onset o...
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The concentration of oestradiol was measured by radioimmunoassay in ovarian venous plasma collected from ewes of three breeds (Finnish Landrace, Scottish Blackface and Tasmanian Merino) on Day 9 of the oestrous cycle and in jugular venous plasma collected daily around oestrus in two of these breeds. The mean +/- s.e.m. concentration in the ovarian venous plasma of the Merino (44.1 +/- 7.6 pg/ml...
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Longitudinal ultrasound, behaviour and endocrine evaluations were conducted, over 14 to 18 months, in two young female Indian rhinoceroses (Rhinoceros unicornis) to characterize the oestrous cycle. Both females showed the same pattern of follicular development producing a large follicle (10-12 cm diameter) on one of the ovaries that persisted for 8.5 +/- 4.68 days before spontaneously ovulating...
متن کاملEffect of the stage of the oestrous cycle on the follicular population in pony mares.
In the middle of the breeding season, 16 pony mares (n = 4 per day) were slaughtered on four different days (days 6, 14, 17 and the preovulatory day) of the oestrous cycle, day 0 being the day of the last ovulation. All the ovaries were examined histologically; the number, size and atresia (defined by granulosa cell pyknosis) of all follicles larger than 1 mm in diameter were studied, using a K...
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ژورنال
عنوان ژورنال: Reproduction Nutrition Développement
سال: 1985
ISSN: 0181-1916
DOI: 10.1051/rnd:19850101