COMPARISON OF STAINING TECHNIQUES FOR SPERM MORPHOLOGICAL EVALUATION IN CANINE SEMEN

Abstract

The growth of multispecies families in Brazil highlights the need for ethical and high-quality reproductive practices, especially when it comes to breeding dogs. Success in reproduction depends on several factors, and the seminal evaluation, especially the sperm morphology, is extremely valuable, with emphasis on the complete andrological examination to ensure the reproductive performance of the male. Different staining techniques are used with the purpose of evaluating sperm morphology and diagnosing possible alterations that may compromise the fertility of the animal. Among the commonly used colorings, Panopticon Rapid, Giemsa, Eosin-nigrosine, Methylene Blue and Rose Bengal stand out. Each dye has its particularities, highlights, advantages and limitations in terms of sensitivity, practicality and detailing of sperm structures. The choice of the most appropriate stain for sperm evaluation should be based on the main purpose of the exam, which is the identification and characterization of morphological changes in spermatozoa. In addition, the durability time of the stained blade and the quality of the dyes used must be considered, since these factors directly impact the accuracy of the results obtained. These techniques allow better visualization of sperm structures, favoring the distinction between major and minor defects, as well as the differentiation between viable and nonviable spermatozoa. The adoption of effective staining methods is essential for more accurate diagnoses, contributing to decision-making and greater efficiency of assisted reproduction programs.