Asociación entre calidad de ovocitos recuperados y condición corporal en vacas criollas

Abstract

Criollo high Andean cattle are of family economic importance for rural dwellers and contribute to food security. The objective of this study was to evaluate the quantity, quality, and nuclear status of ovarian oocytes according to the body condition of Criollo cows. Groups of cows were formed according to the body condition (1=emaciated, 5=obese): low (≤1.5), moderate (2 to 2.5) and high (≥3). Ovaries (n=212) were obtained from Criollo cows from the slaughterhouse. Oocytes were recovered by follicular aspiration classifying them into categories A, B, and C, placing a portion with ethanol-acetic acid (3:1) for 24 h, then stained with 2% Lacmoid. The nuclear status of the oocyte was evaluated, categorized as intact germinal vesicle (GV) and broken germinal vesicle (GVBD). The number of oocytes recovered per ovary among low, moderate, and high body condition cows were similar (p>0.05). There was an association between body condition and oocyte quality of category A (rs=0.49; P=0.001), B (rs=0.16; P=0.018); C (rs=-0.16; P=0.016). Higher percentages (p≤0.05) of oocytes of categories A and B were obtained in those of moderate and high body condition, as category C in low body condition. Body condition did not influence (p>0.05) oocyte nuclear status. No association was found (p=0.073) between body condition and oocytes with intact GV, nor with GVBD (p=0.737). It is concluded that body condition is associated with the quality of oocytes of category A, B and C, but not with the nuclear status of GV and GVBD in Criollo cows from the slaughterhouse.