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Indian Journal of Geo-Marine Sciences (IJMS) >
IJMS Vol.40 [2011] >
IJMS Vol.40(5) [October 2011] >
| Title: | Reproductive pattern and some biological features of anadromous fish tenualosa ilisha (family: clupeidae) from Pakistan. |
| Authors: | Panhwar, Sher Khan
Siddiqui, Ghazala
Ayub, Zarrien |
| Issue Date: | Oct-2011 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | This
study is the first to describe the reproductive pattern of anadroumous fish Tenualosa ilisha based on the histological
examination of male and female gonads. The overall sex-ratio was close to 1:1
ratio. The five stages of oogenesis, nearly ripe, fully developed, running
ripe, partially spent and spent and four distinct phases of ovarian atresis
alpha, beta, gamma and delta were observed. Five stages of spermatogenesis
developing, nearly ripe, ripe, partially spent and spent were identified. The
male and female specimens in ripe and partially spent stages were considered to
be in spawning condition. The spawning males were encountered during the period
from May to October with the highest in July, August and October. While
spawning females were also observed during the period from May to October, with
almost all females being in spawning condition. The length-weight relationship
in females of T. ilisha was nearly isometric and in males was
allometric. The relationship between fecundity and other variables i.e. total
length, body weight, girth and ovary weight in this species was significant.
The age estimated on the basis of scales radii and length of the scales showed
that the age classes comprised of 1+ to 3+ years. The mean scale length in
different length groups was 7.5 to 11.5 mm. |
| Page(s): | 687-696 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-1033 (Online); 0379-5136 (Print) |
| Source: | IJMS Vol.40(5) [October 2011]
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