ÍNDICE DE PRENHEZ E VIABILIDADE ECONÔMICA DA IATD EM BOVINOS DE CORTE EM DUAS PROPRIEDADES RURAIS NO ESTADO DE GOIÁS

Abstract

One of the technologies used to increase the reproductive performance of beef cattle is fixed-time artificial insemination (IATF). The objective of this study was to evaluate the effect of Nelore, bull, property, cattle categories on pregnancy rates, as well as the economic viability of fixed-time artificial insemination in two farms in the state of Goiás. 2210 hormonal protocols, fixed-time artificial insemination (IATF) and pregnancy diagnoses performed on 1417 Nellore cattle collected during the breeding season from November 2018 to March 2019. On farm 1 we evaluated data from 280 heifers, 49 farmed multiparous cows and 63 single multiparous cows, on farm 2 of 547 farmed multiparous cows, 324 single multiparous cows, 99 single primiparous cows and 55 calved primiparous cows with body condition between 2.50 to 3.50 (Scale 1 : too thin at 5: too fat). The protocols used were three managements, first in D0, second in D8 and third in D10. All bovine females on D0 (day zero) received rectal palpation with the use of ultrasound to diagnose pregnancy. If the pregnancy was not negative, they received an intra vaginal progesterone (P4) implant (single dose). Along with 2 ml estradiol benzoate, heifers and single cows were given 1 ml (PGF2α) prostaglandin on D0. After 8 days (D8) he removed the implant, then injected 1 ml for heifers and 2 ml for single cows and estradiol cypionate calves, 1 ml (PGF2α) prostaglandin, 1.5 ml (eCG) equine serum gonadotropin, all injectable drugs were administered intramuscularly. 48 hours after the application of the drugs performed at D8, artificial insemination (AI) was performed. The pregnancy diagnosis (GD) was made 28 to 35 days after AI by ultrasound. IATF pregnancy data were subjected to the effects of bull, animal category, time of year, rural property and number of IATF per matrix using the chi-square statistical method at 5% significance.