Postpartum follicular development in Brahman cows under two stocking rates
Por:
Rubio, I, Castillo, E, Soto, R, Alarcon, F, Murcia, C, Galina, CS
Publicada:
1 mar 2010
Resumen:
The aim was to study postpartum follicular population dynamics in Brahman cows in the Mexican humid tropics and under different stocking rates. Lactating adult cows (n = 104) grazed native grammas (Paspalum spp., Axonopus spp.) under two stocking rates: 2.8 (high) or 1.7 (low) cows/ha. Follicle numbers and their size (millimetres) were measured by ovarian ultrasound scanning. Animals detected in oestrus and inseminated were taken out of the study. Both stocking rates produced similar (P < 0.05) body condition scores (BCS) and follicular dynamics. The percent of follicles, averaged over stocking rates, of < 4 mm diminished and those of 5-8 mm increased with time, whilst those of > 9 mm remained constant; respective values for the previously mentioned sizes were 60 days postpartum (n = 101), 49%, 56% and 5%; 120 days (n = 70), 28%, 66% and 6%; and 180 days (n = 15), 9%, 79% and 12%. There was a positive correlation between BCS and follicle number for size < 4 mm (r = 0.73, P < 0.01), whi
Filiaciones:
Rubio, I:
Univ Nacl Autonoma Mexico, Ctr Ensenanza Invest & Extens Ganaderia Trop, Fac Med Vet & Zootecnia, Tlapacoyan, Veracruz, Mexico
Castillo, E:
Univ Nacl Autonoma Mexico, Ctr Ensenanza Invest & Extens Ganaderia Trop, Fac Med Vet & Zootecnia, Tlapacoyan, Veracruz, Mexico
Soto, R:
Univ Nacl Autonoma Mexico, Dept Reprod, Fac Med Vet & Zootecnia, Mexico City 04510, DF, Mexico
Alarcon, F:
Univ Nacl Autonoma Mexico, Dept Reprod, Fac Med Vet & Zootecnia, Mexico City 04510, DF, Mexico
Murcia, C:
Univ Nacl Autonoma Mexico, Dept Reprod, Fac Med Vet & Zootecnia, Mexico City 04510, DF, Mexico
Galina, CS:
Univ Nacl Autonoma Mexico, Dept Reprod, Fac Med Vet & Zootecnia, Mexico City 04510, DF, Mexico
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