The 'hybrid' character of the gametes and reproductive tracts of the African shrew, Myosorex varius, supports its classification in the Crocidosoricinae

Journal of Reproduction and Fertility
J M BedfordR M Baxter

Abstract

The Soricidae are generally considered to comprise two subfamilies--Crocidurinae and Soricinae--each of which has distinctive reproductive characteristics. Although Myosorex varius is classified as a crocidurine, the features of its reproductive system call that classification into question. Compared with three other shrew genera, Myosorex exhibited a number of specific features including a relatively prolonged time (about 22 h) for ovulation to be induced by hCG injection and the smallest diameter (75 microns) recorded for any mammal egg. Moreover, the relative testis mass and the number of epididymal spermatozoa were somewhat greater than in some other shrews studied recently. However, many reproductive features in Myosorex have a 'hybrid' character. The glans penis has spines similar to those evident in crocidurines but absent in soricines, yet the accessory sperm storage site, midway along the vas deferens, is similar to that in soricine shrews. The ultrastructure of Myosorex spermatozoa was primarily soricine, despite an unduly large acrosome, which reaches its apogee in the Crocidurinae. Whereas the Fallopian tube displays a crocidurine-type isthmus characterized by deep crypts throughout, the ampulla is richly endowed wi...Continue Reading

Citations

Feb 7, 2001·Annals of Anatomy = Anatomischer Anzeiger : Official Organ of the Anatomische Gesellschaft·C A de Oliveira, G A Mahecha
Feb 3, 2005·Biological Reviews of the Cambridge Philosophical Society·J Michael BedfordSteven M Goodman
Dec 3, 2003·Differentiation; Research in Biological Diversity·Gen YamadaGerald R Cunha
Apr 9, 1999·International Journal of Andrology·R C Jones

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.