World Applied Sciences Journal 30 (12): 1784-1790, 2014 ISSN 1818-4952 © IDOSI Publications, 2014 DOI: 10.5829/idosi.wasj.2014.30.12.14265 Corresponding Author: M. Hussain, Department of Zoology, University of Gujrat, Gujrat, Pakistan. 1784 Comparative Study to Monitor the Survival and Growth of Varying Fish Species Ratios under the Same Stocking Density M. Hussain, S.M. Hussain, M.W. Mumtaz, 1 2 3 M.N. Abbas, Ahtasham Raza and M.S. Mubarik 1 4 2 Department of Zoology, University of Gujrat, Gujrat, Pakistan 1 Department of Zoology, Wildlife and Fisheries, GC University Faisalabad, Pakistan 2 Department of Chemistry, University of Gujrat, Gujrat, Pakistan 3 Integrated Environmental Lab, Lahore, Pakistan 4 Abstract: The experiment was conducted to examine the effect of equal stocking density (180 fish/pond) with varying species ratios (90:60:30, 60:90:30 and 75:75:30) of Labeo rohita, Cirrhinus mrigala and Tilapia nilotica one (T ), two (T ) and three (T ), respectively for growth performance and survival rates. Fish species were fed 1 2 3 once daily at the rate of 2% of body weight. Comparison of means revealed significantly higher average body weight in T (90.10 ±13.79 g) followed by T (74.07 ±13.01 g) and T (79.71 ±12.2 g), moreover analysis of 1 2 3 a c b variance showed highly significant (p<0.01) difference in body weight among treatments. The gross (2057.5 kg) and net (2002.2 kg) fish production/hectare/year was also higher in T than T and T . Furthermore 90:60:30 1 2 3 stocking ratio in T was found most suitable compared to 60:90:30 in T and 75:75:30 in T , for Labeo rohita, 1 2 3 Cirrhinus mrigala and Tilapia nilotica. Hence, the present study showed that the optimal ratio of major carp to tilapia in polyculture can efficiently utilize available resources for maximum production. Key words: Stocking ratio Growth Survival Fish production Polyculture INTRODUCTION including, type of organisms consumed, consumption Aquaculture has been encouraged in all over the The general practice is to divide fish into different types globe for its contribution in economy, nutrition and according to their foraging in natural habitats, such as healthy food for man [1, 2]. It is a low energy expenditure phytoplankton, zooplankton, benthic animals, and protein yielding in comparison to other sectors [3]. macrophytes, or detritus feeders. The distinction between Furthermore aquaculture is one of the fastest-growing the different feeding habits is not always absolute. food-producing sectors in the globe and during recent Although species such as rohu (Labeo rohita), mrigal decades total production has been significantly improved (Cirrhinus mrigala) and tilapia (Tilapia nilotica) are compared to previous decades. This improvement in omnivorous, their adaptability varies in different climatic production has been achieved through semi-intensive conditions [8]. polyculture in ponds [4, 5]. Pakistan has been blessed Specific interactions among fish species are with vast area of both marine and inland fisheries important in the sustenance of composite culture [9]. resources, which have great development potential and Suitable selection of fish species can boost nutrient flux can support a variety of fish species of nutritional and and maximization of the productivity, both in terms of economic importance [6]. quantity and quality [10]. Moreover fish growth depends Global aquaculture production is largely influenced upon the stocking density. The species cultured at lower by the culture of major carps and other cyprinids [7]. stocking density with a low cost diet can enhance the fish However questions still exist relating to fish food, growth performance [11]. However the impact of stocking mechanisms, digestibility and nutritive value of plankton.