Ovarian, endocrine and molecular alterations from Bos Taurus and Bos indicus heifers submitted to different nutritional challenges

• Grant number: 12/00889-5
• Support Opportunities: Regular Research Grants
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Pietro Sampaio Baruselli
• Grantee: Pietro Sampaio Baruselli
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Emiliana de Oliveira Santana Batista

Abstract

The amount of food/energy ingested by Bos taurus and Bos indicus heifers affect the characteristics of their estrous cycle, such as ovarian structure dimensions and circulating concentration of steroidal hormones. Studies have been demonstrated that the maximum size of the dominant follicle and corpus luteum is higher in taurine than in zebu females, what can suggest a higher steroidal hormones production in taurine. In contrary, literature has shown that zebu females use to produce more steroidal hormones than taurine in the same livestock system. It is believed that this lower concentration of steroid hormones in female taurine is due to increased hepatic metabolism related to the higher dry matter intake, especially in animals selected for high milk production. This difference in hormone concentrations may reflect differences in fertility among these groups. Zebu females in the highest concentration of steroid hormones influence the response of these animals to TAI protocols. Zebu heifers with the highest concentration of progesterone at the time of administration of ovulation inducer had decreased ovulation rates. Thus, the objectives of this study are to evaluate heifers Bos indicus, Nelore (n = 32) and Bos taurus heifers, Holstein (n = 32) under high and low dry matter intake / energy, the profile of secretion of luteinizing hormone (LH)and progesterone, follicular growth , ovulation rate and gene expression in liver tissue of enzymes related to metabolism of progesterone, namely cytochrome P450 2C, cytochrome P450 3A and aldo-keto-redutase (AKRC1). (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BATISTA, E. O. S.; DEL VALLE, T. A.; ORTOLAN, M. D. D. V.; RENNO, F. P.; NOGUEIRA, G. P.; SOUZA, A. H.; BARUSELLI, P. S.. The effect of circulating progesterone on magnitude of the GnRH-induced LH surge: Are there any differences between Bos indicus and Bos taurus heifers?. Theriogenology, v. 104, p. 43-48, DEC 2017. (12/00889-5)

BATISTA, E. O. S.; SALA, R. V.; ORTOLAN, M. D. D. V.; JESUS, E. F.; DEL VALLE, T. A.; RENNO, F. P.; MACABELLI, C. H.; CHIARATTI, M. R.; SOUZA, A. H.; BARUSELLI, P. S.. Hepatic mRNA expression of enzymes associated with progesterone metabolism and its impact on ovarian and endocrine responses in Nelore (Bos indicus) and Holstein (Bos taurus) heifers with differing feed intakes. Theriogenology, v. 143, p. 113-122, FEB 2020. (12/00889-5)

BATISTA, E. O. S.; MACEDO, G. G.; SALA, R. V.; ORTOLAN, M. D. D. V.; SA FILHO, M. F.; DEL VALLE, T. A.; JESUS, E. F.; LOPES, R. N. V. R.; RENNO, F. P.; BARUSELLI, P. S.. Plasma Antimullerian Hormone as a Predictor of Ovarian Antral Follicular Population in Bos indicus (Nelore) and Bos taurus (Holstein) Heifers. REPRODUCTION IN DOMESTIC ANIMALS, v. 49, n. 3, p. 448-452, JUN 2014. (12/00889-5)