Reproductive performance of Zebu compared with Charolais × Zebu females in a humid tropical environment

Abstract

Components of reproductive efficiency of Zebu-type and Charolais x Zebu-type (1/2, 3/4 and 7/8) females were compared. Zebus had longer mean intervals from calving to first service (57-8 days) and from calving to conception (46-0 days). Least squares means for both traits were respectively 129-8 and 145-1 days. Correspondingly, in the Charolais cross group 26-4% more cows were detected in oestrus within 180 days of calving, and 31-4% more conceived in the same period. Least squares means for these traits were respectively 80-7 and 50-5%. No significant differences were found between the two breeding types either in number of services per conception or in the percentage conceiving by artificial insemination (of those showing oestrus) both for lactating and dry females. A higher percentage of oestrus cycles of normal duration was found in Charolais cross (72-9 %) than in Zebus (63-1 %). Gestation lengths of Zebus (Indu-Brasil sires) and Charolais cross (Charolais and Simmental sires) were respectively 288-8 and 283-1 days. The main difference between breed types was the longer lactation anoestrus shown by Zebus. These were very sensitive to seasonal effects, showing a cyclical time trend with peaks of shorter anoestrous periods for cows calving in January-February-March, and longer ones for cows calving in July-August-September. Related traits followed parallel cycles. Charolais cross cows showed less variation than Zebus.

Reproductive performance of dairy cattle at Asella livestock farm, Arsi, Ethiopia. I: Indigenous cows versus their F1 crosses

“…The apparent superiority of F 1 crosses over their indigenous contemporaries for this trait is in agreement with the reports of M adalena and H injosa (1976). They found 168 and 122 days open for Zebu and Charoloais × Zebu crosses, respectively.…”

Body weights at weaning and 18 months of Zebu, Brown Swiss, Charolais and crossbred heifers in south‐east Mexico

“…To the authors’ knowledge this is the first report on growth performance of grading up crosses of BS and CH in Mexico. Under tropical conditions crossbred cattle have performed better than Z cattle for age at first calving (Magaña & Segura 2001) and postpartum reproductive traits (Madalena & Hinojosa 1976; Magaña & Segura 2001). Among the BS crosses the F 1 and backcross heifers had the highest BW18.…”

Induction of ovulation with GnRH and PGF2a in lactating Bos taurus × Bos indicus cows

“…Several factors could be responsible for this low pregnancy rate, including genotype and BCS of the females, calf presence and the season of the year. In this respect, tropical cattle show an overall poor reproductive efficiency (Madalena and Hinojosa, 1976), and early weaning (2 to 3 months of age) increases pregnancy rates in some Zebu-cross herds (Schlink et al, 1994). Although in the present study BCS did not affect the number of pregnant Ovsynch cows, it can be mentioned that their BCS was low.…”