Qualitative and quantitative changes in testes of Cirrhinus mrigala (Ham.) through multiple induced stripping

Abstract

Quantitative evaluation of the male gonad and gametes in Cirrhinus mrigala was studied in seasonal cycle as well as in the multiple stripping sequences during breeding season to assess the efficacy of males for multiple uses. The peak GSI was observed during July and least in January. The matured testes during June showed a GSI 2.175±0.01 that reduced to 0.88±0.01 soon after stripping. The same again increased up to 1.81±0.08 within 4 weeks in brood rearing ponds. The milt yield, spermatocrit value and sperm count reduced drastically in first week after first stripping (milting) and slowly increased on fourth week. The histo-anatomical study of testes through seasonal cycle and during intermilting (stripping) period implies that the testes do not enter to any resting phase in later. The sequential growth of germ cells in spermiogenesis completed within few weeks during inter-milting period in a multiple sequence of milting. The spent male broods were found to be ready for subsequent use within 30 days after first stripping