Genetic Diversity of Creole Sheep Managed by Indigenous Communities of the Central Region of Veracruz, Mexico.

In the indigenous communities of central Veracruz, herds of creole sheep have been established and managed through traditional practices of crossing, but their genetic characteristics have never been examined in order to evaluate their state of endogamy, and to help the management programs to protect this genetic resource. The objective of the present study was to characterize the genetic diversity of three populations of creole sheep managed by indigenous communities in the central region of Veracruz, Mexico. Indigenous family producers of creole sheep were located and blood samples taken from 90 individual sheep from the municipalities of Tehuipango, Astacinga and Tlaquilpa, Veracruz.

Administration of exogenous hormones in ovulatory and embryonic response in Pelibuey sheep.

The objective of this study was to evaluate the effect of two sources of commercial porcine pituitary-derived follicle-stimulating hormone (pFSH) and pFSH-porcine Luteinizing Hormone (pLH), including equine chorionic gonadotropin (eCG), in ovulatory and embryonic response in Pelibuey sheep. Twenty-four Pelibuey sheep were used and were assigned randomly to four treatments (n = 6): (T1; 200 mg pFSH-Folltropin ); (T2; 200 mg pFSH + 300 UI eCG-Folligon ); (T3; 250 UI pFSH/pLH-Pluset ) and (T4; 250 UI pFSH/pLH + 300 UI eCG). The interval of hours from withdrawal of the device to the beginning of oestrus (BO) was lower (p < .

The influence of nutrition on the insulin-like growth factor system and the concentrations of growth hormone, glucose, insulin, gonadotropins and progesterone in ovarian follicular fluid and plasma from adult female horses (Equus caballus).

Background: Feed intake affects the GH-IGF system and may be a key factor in determining the ovarian follicular growth rate. In fat mares, the plasma IGF-1 concentration is high with low GH and a quick follicular growth rate, in contrast to values observed in thin mares. Nothing is known regarding the long-term effects of differential feed intake on the IGF system.

Effects of nutritional cues on the duration of the winter anovulatory phase and on associated hormone levels in adult female Welsh pony horses (Equus caballus).

Background: Mares have an annual reproductive rhythm, with a phase of inactivity in midwinter. The aim of this study was to determine the impact of food restriction on physiological and metabolic hallmarks of this rhythm.

Methods: Over three successive years, 3 groups of 10 mares were kept under natural photoperiod.