Reproductive features of the eastern mole (Scalopus aquaticus) and star-nose mole (Condylura cristata)

• Published in: Journal of reproduction & fertility Vol. 117; no. 2; pp. 345 - 353
• Main Authors: Bedford, J M, Mock, O B, Nagdas, S K, Winfrey, V P, Olson, G E
• Format: Journal Article
• Language: English
• Published: England Society for Reproduction and Fertility 01-11-1999
• Subjects: Animals; Chorionic Gonadotropin - pharmacology; Fallopian Tubes - anatomy & histology; Female; Male; Moles - physiology; Ovulation Induction; Ovum - cytology; Penis - anatomy & histology; Reproduction - physiology; Shrews; Species Specificity; Spermatozoa - cytology; Testis - anatomy & histology; Vagina - anatomy & histology; Vas Deferens - anatomy & histology
• ISSN: 1470-1626; 0022-4251; 1741-7899
• DOI: 10.1530/jrf.0.1170345

Since moles are closely related to shrews, the gametes and reproductive tracts of the star-nose mole ( Condylura cristata ) and the eastern mole ( Scalopus aquaticus ) were examined to gain further insight into unusual reproductive traits of the Soricidae. Moles display many of these soricid
traits, but with some important differences. The cumulus oophorus of Scalopus , ovulated about 16 h after hCG injection, was largely dispersed by hyaluronidase and, though quite dense, was nevertheless
more similar to that of higher mammals than to the compact 'ball' of the soricid cumulus. Within the female tract in these
moles, approximately 85% of the length of the oviduct comprises a narrow ampulla with numerous differentiated crypts that,
in shrews, house spermatozoa. However, in contrast to shrews, moles produce considerably larger numbers of spermatozoa, which
challenges the proposal that, in shrews, oviductal sperm crypts specifically permit lower sperm production by the males. In
the sperm head of these two moles, the acrosome displays the long rostrum that is typical of other Insectivora, and the perforatorium
has the barbs by which soricid spermatozoa probably bind to the zona pellucida. Perhaps allied to this, immunoblots indicated
that the immunoreactive acrosomal matrix of Scalopus spermatozoa is simpler than the polypeptide complex of the bovine and hamster acrosomal matrix.