Associação da medroxiprogesterona ao protocolo Ovsynch para inseminação artificial em tempo fixo de búfalas cíclicas (Bubalus bubalis) criadas na Amazônia Oriental

Abstract

The aim of this study was to evaluate the effect of the association of medroxyprogesterone with the Ovsynch protocol on the follicular growth, ovulation, and conception rate of buffaloes in the Eastern Amazon (Tracuateua-PA). Twenty-seven cyclic, non-lactating females (G1 n=14 and G2 n=13) with a 3.5 BCS were synchronized with the Ovsynch. Animals from G2 received a supplementation of 60 mg of medroxyprogesterone from D0 to D7 (D0=starting day of treatment). Ultrasonography evaluation on ovaries was realized on Days 0, 7, 9, and 10. A significant effect of treatment on follicle number was observed on D7 (G1: 4.57±0.60 versus G2: 6.54±0.67; P=0.05). Time and treatment influenced follicular diameter on D7. The growth of the dominant follicular was increased from D7 to D9 on treated females (G1: 2.05±0.49 mm/day versus 3.48±0.41 mm/ day; P<0.05). G1 animals (35.71% versus 30.77%) ovulated comparatively earlier than their G2 counterparts, but this did not affect the conception rates (G1: 50,00% and G2: 30,77%; P>0,05). The findings suggest that medroxyprogesterone: (1) increases follicular recruitment and inhibits the growth of follicles whose diameter was larger than 5.0mm from D0 to D7; (2) the withdrawal of medroxyprogesterone speeds up follicular growth 1.7 fold from D7 to D9; (3) would probably contribute to the ovulation of larger follicles thereby forming more luteal tissue; (4) does not stimulate early ovulation after Ovsynch; and (5) does not elevate the conception rate after the synchronization of cyclic females with good body condition, and should be evaluated for the utilization in acyclic/reduced BCS females.

A suplementação alimentar com ácidos graxos insaturados melhora a qualidade do sêmen criopreservado de búfalos (Bubalus bubalis) pós descongelação

“…Em geral, os programas de inseminação artificial em bubalinos são executados tendo como base o uso do sêmen congelado (GARCIA et al, 2008). Contudo, tanto no bubalino como em outras espécies, o processo de criopreservação causa inúmeras injúrias nas células espermáticas, as quais ocasionam decréscimo ou perda da capacidade de fertilização (SANSONE;NASTRI;FABBROCINI, 2000).…”

Production, chemical composition, and fatty acid profile of milk from buffaloes fed with cupuaçu (Theobroma grandiflorum) cake and murumuru (Astrocaryum murumuru) cake in the Eastern Amazon

“…In order to concentrate the parturition period and contribute to data collection uniformity, females had their estrus synchronized and were submitted to fixed‐time insemination after OvSynch protocol. This procedure is based on two injections of a GnRH analogue (lecirelin, 50 μg IM) 9 days apart and a single administration of prostaglandin analogue (d‐cloprostenol, 150 μg IM) on the seventh day (Garcia et al, 2008). Artificial insemination was performed without estrus observation.…”