VPA 211: General Veterinary Parasitology and Helminthology (3+1)

REPRODUCTIVE SYSTEM

Digenetic trematodes are hermaphrodite except the members of family Schistosomatidae.

Male reproductive system

• In male, two testes are present, which may be spherical, lobed or divided into number of small bodies.
• The vasa efferentia unite to form a vas deferens. The vas deferens widens distally to form vesiculum seminalis and ends in a cirrus or penis. Cirrus may be enclosed by cirrus sac.

Female reproductive system

• Consists of ovary, which discharges the ova into the oviduct. Oviduct bears “receptaculum seminalis” and a narrow a canal (Laurers canal).
• A pair of vitelline gland or vitellaria with number of follicles are placed laterally, which discharges into the yolk duct. Yolk duct joins with oviduct in a special widen portion – Ootype.
• Ootype is surrounded by Mehlis (unicellular) gland. Mehlis and yolk gland collectively known as shell gland.
• Eggs after leaving the ootype enter into the uterus. The uterus may be short or much convoluted and open through genital pore is situated anterio-ventral surface or posterio-lateral.
• Genital pore is surrounded by sinus or atrium. In some species, the sinus or atrium develop into sucker known as genital sucker.
  • Eg. Cotylophoran cotylophorum.
  • Click here for Reproductive system picture