Dinâmica folicular ovariana em potras pré-púberes e púberes

• Autor(a) principal: Gomes, Luiz Gustavo
• Data de Publicação: 2003
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5207
• topic: Puberdade; Potras; Dinâmica folicular; Puberty; Fillies; Follicular dynamics; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::REPRODUCAO ANIMAL

The experiments of the present study were developed with the objectives of verifying the effect of the birth season on the first ovulation of fillies, to characterize some follicular parameters of fillies and to compare the occurrence of the first ovulation of the season, as well as some ovarian characteristics among fillies and mares. In addition, the relationship between the body condition and the hair coat length with the ovarian follicular activity were studied. Crossbred Breton Postier fillies (n=14) and mares (n=22) were used during three consecutive reproductive seasons. On Experiment 1, fillies born in the summer were used (Summer Group; n = 9, age = 8.5 ± 0.2 month old) and mares (Control Group; n = 5, age = 76.0 ± 10.2 months old). On Experiments 2 and 3, the animals used were divided into three Groups: Summer Group (fillies born in the summer; n = 9, age = 18.8 ± 0.2 month old and n = 6, age = 31.9 ± 0.3 month old), Spring Group (fillies born in the spring; n = 5, age = 10.1 ± 0.6 month old, and n = 5, age = 23.3 ± 0.6 months old) and Control Group (adult mares; n = 9, age = 91.4 ± 4.3 months old and n = 8, age = 82.5 ± 12 months old), respectively. Ovarian and uterine parameters were evaluated by ultrasonography. Every 14 days, the weight, the body condition score and the hair coat lengths were evaluated in the 3 experiments. Based on the results of this present study, it can be concluded that: a) the birth season influences the beginning of puberty in fillies; b) the fillies start the reproductive season later than the mares; c) the follicular development occur in waves in prepubertal fillies; d) the ovarian activity between mares and fillies is pretty similar during the transition phase and the interovulatory intervals, when only quantitative differences, not qualitative differences, can be observed; e) apparently the follicles of prepubertal fillies present estrogenic activity, since it was observed a positive correlation among the follicular diameters and the uterine echotexture; f) the body condition score, the weight and the hair coat length, during the prepubertal and pubertal phases, presented correlation with the ovarian follicular activity in fillies.