ABSTRACT
BACKGROUND: The common marmoset (Callithrix jacchus) is of interest for reproductive studies because of their high and variable fertility in captivity. However, to understand this variability, much basic information still needs to be gathered. This study is the first to characterize marmoset semen comparing a German and a Brazilian colony. METHODS: All animals were weighted, and semen samples were collected by penile vibratory stimulation and analyzed according to standard criteria. RESULTS AND CONCLUSIONS: The German animals had a higher mean and maximum weight than the Brazilian. Further, sperm concentration tended to be higher with heavier animals in the German population, but not in the Brazilian. Additionally, major defects tended to be more frequent with higher weight but also only in German sample. In spite of these differences, the total range and variability in sperm concentration were similar in both populations, suggesting that this is characteristic for the species.