Читать книгу Bovine Reproduction - Группа авторов - Страница 372

Walsh et al. [100] reported that maternal age affected the number of antral follicles detectable by ultrasonography in the ovaries of the daughters at a year of age. Holstein heifers that were born to heifers had fewer antral follicles detectable by ultrasonography at a year of age than Holstein heifers that were born to multiparous cows. Similarly, Angus heifers with diminished numbers of antral follicles detectable by ultrasonography (14.5 ± 0.8 follicles) had dams that were younger than the dams of Angus heifers with increased numbers of antral follicles (31.1 ± 0.8 follicles) [101]. These studies suggest that the lesser number of antral follicles detectable by ultrasonography in heifers born to primiparous dams is due to fewer ovarian follicle reserves. Selecting replacement heifers from mature dams may result in daughters with greater fertility and reproductive longevity; however, further research is necessary to determine if interactions between size of the ovarian follicle reserve and age at puberty influence fertility and reproductive longevity in replacement heifers.