Suplementación con selenio, respuesta superovulatoria y recuperación de embriones en bovinos lecheros tratados con eCG

Abstract

ABSTRACT: This study was designed to evaluate the effect of Se supplementation on the superovulatory response and embryo recovery in dairy lactating bovines treated with eCG. Twenty—three Black Friesian lactating cows were selected, from which heparinized blood was taken 20 days prior to the superovulatory treatment in order to determine the blood activity of GSH-Px. The control group (n=11) received 5 ml i.m. of distilled water, and the treated group (n=12) received 5 mg Se/100 kpw i.m. The superovulatory treatment was given between the 9th and 11th day after the estrous cycle, with each cow receiving 2500 UI i.m. of eCG. Prior to insemination, the cows were injected with 750 µg i.m. of tiaprost,  and inseminated twice after 48 hours. The ovarian response was evaluated by ultrasonography, and the embryos were recovered by a non-surgical method. The results were analyzed by a “t” test. The use of Se did not produce significant changes on the GSH-Px activity (P>0.05). The number of follicles found in the treated group was higher than in the control group (P<0.05); however, the number of corpus luteum, ova–embryos and freezable embryos was similar in both groups (P>0.05). The recovery rate of ova– embryo was 63% and 59% for the control and treated group, and the rate of freezable embryos was 33% and 61% for the control group and treated group, respectively. Accordingly, the use of Se in lactating dairy bovines increased the number of follicles, but it did not affect the rate of ovulations and embryo recovery.

Keywords:

antioxidantes

estrés oxidativo

minerales

superovulación

Antioxidant

oxidative stress

minerals

superovulation

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