Influence of the addition of vitamin E in extenders in the quality of fresh semen diluted, refrigerated and frozen semen in dogs of French Bulldog breed / Influência da adição de vitamina E em meios diluentes na qualidade do sêmen fresco diluído, refrigerado e congelado em cães da raça Bulldog Francês

ABSTRACT

Background: Researches have been conducted in order to maintain the quality of the fresh semen which is diluted, refrigerated or frozen in liquid nitrogen for artificial insemination purposes in dogs. The semen biotechnology cooperates with the development of new formulations of types of extenders which minimize the death of the sperms due to thermal stress during temperature reduction of the refrigeration and freezing curves of the semen. The objective was to study the influence of the addition of vitamin E in types of extenders in the quality of the fresh, refrigerated and frozen semen in dogs of French Bulldog breed. Materials, Methods & Results: Semen samples by digital manipulation were performed on 5 adult dogs, French bulldog breed, five on each dog, totaling 25 ejaculated. The characteristics evaluated in fresh semen were Volume (mL), color, aspect, concentration (x106/mL), sperm motility (%), vigor (1-5) and sperm morphology (%). For refrigerated and frozen semen, motility (%), vigor (1-5) and morphology (%) were analyzed. The ejaculated ones were fractionated in 4 equal parts and diluted in the ratio 1 1 in the following extenders 1 TRIS - Fructose Citric acid + 200 mM of vitamin E; 2 TRIS - Fructose Citric acid; 3 - coconut water (ACP-106®) + 200 mM of vitamin E; and 4 coconut water (ACP-106®). The four aliquots of semen, diluted in the four respective extenders were centrifuged at 1500 g/10 min and the “pellets” formed of sperm from every ejaculated, detached from the tubes wall were diluted homogeneously with the four extenders to the volume of 1.5 mL and filled into 0.5 mL French straws kept under refrigeration at 5oC/4 h after placed in a nitrogen vapor at -120ºC/15 min, and immersed in liquidnitrogen at -196ºC in the sequence stored in identified racks and stored in liquid nitrogen container until the time of thawing in a water bath at 37ºC/30 s for microscopic semen analysis. [...]