GONAD DEVELOPMENT AND HISTOLOGY IN BAGRUS BAYAD CULTURED IN OUTDOOR EARTHEN PONDS

Abstract

Bagrus bayad (Deget) are found in Nigerian freshwaters in River Niger, Benue, Kaduna, and Lake Chad. This feral species were observed to have high growth rate and other aquaculture qualities. 200 live juveniles (`100 males and 100 female) were maintained in 5m2 outdoor earthen pounds for 12 months. The objective was to study some aspects of their biology particularly the gonad development and histology, growth and survival with the aim of introducing the species into aquaculture. The fish were checked regularly at 4 weeks intervals for gonad development and maturity stages. One male and one female were dissected each time and gonads used for histological studies. Gonad development stages were classified according to description by Bruton (1979). Cross sections through the ovaries and testis showed gonads in stages II, III, IV and V. photomicrographs of all the stages observed were made and described. Growth and development continued in the fish under culture and it was concluded that Bagrus bayad could be introduced into aquaculture.