Ultrassonografia na avaliação andrológica de ovinos sem padrão racial definido na região da baixada ocidental maranhense, Brasil

Abstract

The ultrasound exam of the testicles is a noninvasive method of diagnose by image which, associated to an andrologic exam of rams, can provide important data about the reproductive capacity of these animals. Therefore, this study aim was to characterize, ultrasonographically, the testicles structures of ovines, correlating them to the biometric variables and semen. This study was conducted at São Bento-MA township, where 30 rams, with undefined racial pattern, divided according to the age group: age group 1 (AG1): from 3 to 6 months; age group 2 (AG2): from 7 to 12 months; age group 3 (AG3): from 13 to 18 months. Andrologic evaluation followed the patterns established by Colégio Brasileiro de Reprodução Animal (CBRA, 1998) and the ultrasonography done by sagittal and frontal cuts of the testicles, later quantified by histogram gray-scale technique. It was seen that the echogenicity of the testicles’ parenchyma and mediastinum increased with age advance. Semen volume, whirl, motility, vigor and concentration showed qualitative and quantitative increase with the ovines age progression, while the percentage of abnormal spermatozoa decreased. Testicles became elongated in older animals, whereas the increase of scrotum perimeter, length and width became stable after 12 months of age. It appears that the echogenicity of testicular parenchyma is positive correlation with biometrical and seminal variables, with different scales of dependence.