Abstract
The spiny eel, Mastacembelus armatus is one of the most common and economically important inland teleost species of Asia having high market and nutritive values. The demand for the fish is almost always exceeds its supply. Histological analysis of developmental stages of both oocytes and sperrnatocytes maturation were undertaken and dimensions of ovarian oocytes were observed to evaluate the annual reproductive condition of M. armatus during August 2012 to July 2013. Monthly sampling of adult individuals of M. armatus was done from haor region of Kishoreganj district, Bangladesh. Both the gonads were paired, elongated and of unequal in length. The colour of ovaries varied from reddish brown to light yellowish; whereas, testes varied from whitish to creamy or dull white. From the histological study, five stages of oocyte development (oogonia, chromatin nucleolar stage oocyte, perinucleolar stage oocytes, yolk vesicle oocyte, and yolk granule stage) were observed upon their changes in nucleus. Female M. armatus having immature stages of oocytes (early and late perinucleolar stage oocytes) were mostly available in the months of November and December. Yolk vesicle stage oocytes appeared during the months of January and February. Early yolk granule stage oocytes appeared during the months of March and April while late yolk granule stage oocytes were observed during the months of May and June. Oocytes and nuclei diameters were observed ranged from 121050 ?m and 10212 ?m, respectively until ovulation. In male gonads, four stages of spermatogenesis (spermatogonia, spermatocytes, spermatids, and spermatozoa) were distinguished during the study period where spermatids were prominent in January to March and spermatozoa in April to July. From this study, the peak gonadal development of M. armatus is found in June and thus, it is clearly indicated that the fish breed during May to June.J. Bangladesh Agril. Univ. 14(2): 261-269, December 2016
Highlights
The Spiny Eel, Mastacembelus armatus is a common fish species of Indian sub-continent that belongs to the family Mastacembelidae under the order Synbranchiformes
The estimated area of occupancy and extent of occurrence of M. armatus indicate its wide distribution throughout its range, the reduction of its population was speculated based on local accounts collected through field visits and personal communication with local people
Mature male and female M. armatus could be distinguished on the basis of the appearance of the genital papillae
Summary
It is assumed that this species has reduced more than 50% by the last two decades and categorized as endangered species (Ahmed, 2015; IUCN, 2015) This species, needs protection from being extinct through the development of its breeding and culture technique. To evaluate the reproductive potentials of M. armatus, information on the fecundity, reproductive biology, behaviour and breeding season are considered essential (Rahman et al, 2004). There are few reports only on food and feeding habit, rearing technique under laboratory condition, morphometric and meristic measurements, and some aspects of reproductive biology of M. armatus so far available (Serajuddin et al, 1998; Narejo et al, 2003; Rahman et al, 2004; Serajuddin and Pathak, 2012; Alam et al, 2013; Patwary, 2013; Mollah et al, 2013; Gupta and Banerjee, 2016). Basic information on the cyclic changes of the reproductive glands that are important to onset successful breeding strategy of M. armatus is indispensable
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.