Regresar

Seasonal variation of estrous and ovulations in Neuquen-Criollo goats of the Patagonia Argentina

Abstract:

The local Neuquen-Criollo goat has a distinct place in the entire north region of the Patagonian Neuquen State due to its prolificacy and productive ability of high quality meat. Based on morphological and productive differences, two different ecotypes have been characterized: Short Hair and Long Hair goats.The present study was undertaken to characterize and compare the seasonal variations in estrous and ovarian activity in both ecotypes of Criollo goats. Twelve sexually mature Short Hair and 15 Long Hair Nequen-Criollo goats were mantained in natural pastures under extensive rearing and exposed to natural daylength (41 South). During a period of 13 months, daily estrous detection and ovarian activity was monitored by laparoscopy every 20 days was carried out. Onset, duration and end of the estrous and ovulation periods were similar between the two ecotypes (p>0.05). Neuquen-Criollo ecotypes showed a seasonal pattern of sexual activity, characterized by a period of total ovulations (with and without estrous) from late March to early September. A shorter estrous period of 5 months was observed for both ecotypes of Criollo goats, from early April to late August, during which more than 75% of the females showed fertile estrous. There was no significant ecotype effects on the proportion of the estrous cycle accounting for their duration (short, normal and long duration) and category (estrous with ovulation, silent ovulation and estrous behaviour only) (p>0.05). In conclusion, Neuquen-Criollo goats exhibited a seasonal pattern of reproduction. Both Criollo ecotypes showed high similarity in their sexual performance during the breeding season.