Influence of monensin supplementation on serum concentrations of glucose, insulin and progesterone of nonlactating and ovariectomized cows.

• Grant number: 10/10080-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2010
• End date: July 31, 2011
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Production
• Principal Investigator: José Luiz Moraes Vasconcelos
• Grantee: Tiago Leiva
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The experiment will be conducted to investigate the influence of monensin supplementation on serum concentrations of glucose, insulin and progesterone (P4) of nonlactating, ovariectomized cows supplemented with a controlled intravaginal P4-releasing insert (CIDR® 1,9 g of progesterone, Pfizer Animal Health, Brazil). The study will be conducted at the São Paulo State University - Lageado Experimental Station, located in Botucatu, São Paulo, Brazil. Fifteen nonlactating, ovariectomized Gir x Holstein cows will be stratified by body weight and body condition score, and randomly assigned to one of two treatments, in a crossing over design: 1) Control: no supplementation of monensin; and 2) Monensin: daily supplementation of 0.2 g / cow of monensin. Each experimental period will be of 21 days will be maintained in Brachiaria spp pasture, receiving individually 100 g of finely ground corn supplemented or not (according to assigned treatment) with 0.1 g / cow of monensin, once daily. During the adaptation period, cows will also receive one used CIDR (second use). At the beginning of each period they will be inserted one new CIDR, which will remain in cows during the entire experimental period. The treatment will be offered individually once daily. During the experimental period, all the animals will be maintained together in Brachiaria spp pasture.