Collection and analysis of semen from the common marmoset (Callithrix jacchus).

The authors examined the seminal characteristics of 16 male common marmosets (Callithrix jacchus) to provide baseline data for future studies of the reproductive biology of this species. Semen samples were collected by electroejaculation. There was considerable inter- and intra-male variation in all seminal characteristics. The median seminal volume was 30 microliters (range 8 to 85 microliters), and the median total sperm count was 5.1 x 10(6) sperm (range, 0.1 to 43 x 10(6]. The median progressive sperm motility was 48% (range, 10% to 76%), and 49% of the sperm exhibited normal morphology (range, 24% to 81%). Three types of sperm head abnormalities and eight types of tail defects were noted. Tail defects were common (median, 50%; range, 17% to 76%), whereas head defects were relatively rare (median, 4.5%; range, 0% to 24%). The results indicate that semen samples can be routinely collected from this species, but considerable inter- and intra-male variation can be expected. It is therefore important to examine several semen samples from each male marmoset to obtain an accurate seminal picture.