CANINE SEMEN REFRIGERATION IN A NATURAL COCONUT WATER (COCOS NUCIFERA)-BASED EXTENDER.

Abstract

ABSTRACT

Artificial insemination in bitches contributes to the genetic improvement of the species, prevents some sexually transmitted diseases through copulation and allows the reproduction of animals that could not copulate naturally, either for anatomical, geographic or behavioral reasons. However, it is not always possible to use fresh semen, thus requiring a diluent to cool and keep it viable for a certain period. Therefore, the objective of this work was to analyze canine semen diluted in coconut water and refrigerated at 5 ºC at different times. Five Brazilian Hounds were used, performing three semen collections from each animal, with intervals of seven days. The ejaculates were kept at a temperature of 37 ºC and macroscopic (volume, color, appearance and odor) and microscopic (motility, vigor, concentration and sperm morphology) analyzes were performed. Then, the ejaculates were diluted in natural coconut water at a concentration of 200 million sperm/mL, and kept at a temperature of 5 °C for up to 72 hours. At intervals of six, twelve, twenty-four, thirty-six, forty-eight, and seventy-two hours, samples were evaluated for sperm motility and vigor. Fresh ejaculates had an average volume of 6.2 mL, white color, watery to milky appearance, “sui generis” odor, 89.5% sperm motility, 4.3 sperm vigor, average concentration of 418 x106 spermatozoa/mL and 7.3% pathological changes. After the beginning of cooling at 5 °C, the values ​​of motility and vigor decreased over time, with the lowest values ​​found after 48 and 72 hours. The in natura coconut water extender proved to be efficient for cooling canine semen at 5 ºC, keeping it for a period of up to 36 hours after harvest, as recommended by the Brazilian College of Animal Reproduction.