The Bioscan, 4(3): 413-419, 2009
An International Quarterly Journal of Life Sciences
web site: www.thebioscan.in 
LENGTH-WEIGHT RELATIONSHIP OF INDIAN MAJOR CARPS AND A CHINESE 
CARP IN A POLYCULTURE POND AT GOVERNMENT FISH FARM, 
GWALIOR (MADHYA PRADESH)
MEENAKSHI SAXENA AND D. N. SAKSENA*
School of Studies in Zoology
Jiwaji University, Gwalior - 474 011 (M.P.)
E-mail: address dnsaksena@gmail.com


KEY WORDS
Length-weight 
relationship
Condition factor
Culturable carps
Physico-chemical characteristics
Primary productivity
Received on: 05.04.2009 Accepted on: 24.07.2009 *Corresponding Author

ABSTRACT

The length-weight relationship of carps was studied in a polyculture pond at Government Fish Farm, Gwalior from November 2007 to April 2008. In the length weight relation of carps studied, the values of ‘n’ were found to be 2.794 for rohu, 2.618 for catla, 2.10 for mrigala and 2.552 for common carp. Since, the value of ‘n’ was found to be less than 3; the growth of carps cultured was not satisfactory. The values of correlation co-efficient (r) between length and weight for all the four carps (rohu, catla, mrigal and common carp) have been above 0.9. This showed a perfect positive relationship between length and weight of all the carps used in this polyculture. The condition factor for L.rohita has been found from 0.92 to 1.1 with an average of 1.03 for C.catla from 0.1 to 1.5 with an average of 1.05 for C.mrigala, from 1.0 to 2.64 with an average of 1.44 for C.carpio and from 1.1 to 2.1 with an average of 1.74. The absolute and relative growth has also been found better in L.rohita and C.catla in comparison to other carps. The physico-chemical characteristics of the pond suggested that the pond is mesotrophic with moderate quantity of nutrients and can be very well used for stocking of Indian major carps for their cultivation. The mean net gross primary productivity of phytoplankton in the pond was also found to be moderate 204.1 ± 32.76 mg C m-3 h-1 in this pond.