Seasonal changes in testicular ultrasonogram pixel-intensity and their association with semen characteristics in rams

Abstract

mL). Mass and individual sperm motility was expressed in percentage of motile spermatozoa under optical microscope equipped with a warm stage. Sperm concentration was determined by using a Neubauer chamber. Semen smears stained with eosin-nigrosin were used to determine the percentage of live spermatozoa and sperm cell morphology by using a light microscope. Results: The mean testicular pixel intensity was the lowest in winter and increased gradually from breeding season to non-breeding season, reaching its maximum value in summer (P<0.05). Pixel intensity was found to have a significant negative correlation with progressive motility (r=-0.605, P<0.05), and sperm concentration (r=-0.619, P<0.05). It is also positively correlated with the percentage of sperm morphological abnormalities (r=0.666, P<0.05). Conclusions: Pixel intensity values of testicular ultrasonogram in rams undergo marked seasonal changes that are associated with fluctuations in photoperiod and ambient temperature. The resulting values of testicular echogenicity (pixel intensity) throughout the year provide useful reference values for predicting the testicular function in Awassi rams. Hedia Mohamed 1 Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza El-Belely Mohamed 2 Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza Ismail Sayed 3 Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza Abo El-Maaty Amal 4 Department of Animal Reproduction and AI, Veterinary Division, National Research Center, Dokki, Giza Aller JF, Aguilar D, Vera T, Almeida GP, Alberio RH. Seasonal variation in sexual behavior, plasma testosterone and semen characteristics of Argentine Pampinta and Corriedale rams.