COMPARATIVE STUDY, nellore and Angus breeds between oviducts from cows with high or low population antral follicle

• Grant number: 13/02201-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: August 01, 2013
• End date: July 31, 2016
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Marcelo Fábio Gouveia Nogueira
• Grantee: Vinícius Gonçalves Pinheiro
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The bovine follicular growth occurs in a wave pattern which can vary from 2 to 3 estrous cycle and is characterized by the growth of a synchronous group of antral follicles, where only one becomes dominant. The number of follicles is variable between animals and breeds, but has high repeatability between individuals. Some studies have reported that Zebu breeds in the amount of follicles per wave is higher as compared to taurine breeds. This variation in the ovarian follicular population can interfere with female fertility by influencing the oocyte competence (Ireland, 2007). Objective with this project, identify females of Nelore (Bos indicus) and Aberdeen Angus (Bos taurus), which have high and low number of antral follicles recruited by follicular wave, and research histological differences in the lipid profile of the oviduct these animals at fertilization and that may be indicative of a higher fertility (experiment 1). In addition, we will evaluate the fertility (pregnancy rate) in Nelore cows with high or low antral follicle population (experiment 2).