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The study was conducted to assess the growth and survival of Macrobrachium rosenbergii in earthen culture ponds in order to know about the growth potential of M. rosenbergii in mono as well as polyculture conditions in Jammu. Polyculture experiments of prawn with some selected carps Indian Major Carps (Cirrhinus mrigala and Labeo rohita) and Exotic Carps (Cyprinus carpio) were undertaken in 3 freshwater ponds for duration of 4 months. Under the monoculture conditions, prawns attained an average size of 10.40 ± 0.17 cm weighing 23.84 ± 0.32 g in 4 months and the survival rate was found to be more than 75%. The growth rate of prawns was found to increase steadily during the first half (upto mid-October) after which a decline in the growth rate was evident as the mean temperature reached below 18°C. In the polyculture ponds the prawns attained an average size of 10.10 ± 0.03 cm weighing 18.39 ± 0.89g (without C. carpio) and 8.4 ± 0.36 cm weighing 15.23 ± 0.36 g (with C. carpio) in 4 months and their survival rate was less than 70%. Prawns being benthic feeders utilized the leftover food (of the fishes) that settled at the bottom, therefore, saving the feed cost. It was observed that mean size of the fish attained in the polyculture practice was almost similar to that obtained in the monoculture. The ideal prawn polyculture should be practiced with fast growing compatible carps such as Rohu and grass carp. Bottom feeder carps such as Mrigal (C. mrigala) should be avoided in prawn polyculture practice as they compete with prawns in feeding.

The study was conducted to assess the growth and survival of Macrobrachium rosenbergii in earthen culture ponds in order to know about the growth potential of M. rosenbergii in mono as well as polyculture conditions in Jammu. Polyculture experiments of prawn with some selected carps Indian Major Carps (Cirrhinus mrigala and Labeo rohita) and Exotic Carps (Cyprinus carpio) were undertaken in 3 freshwater ponds for duration of 4 months. Under the monoculture conditions, prawns attained an average size of 10.40 ± 0.17 cm weighing 23.84 ± 0.32 g in 4 months and the survival rate was found to be more than 75%. The growth rate of prawns was found to increase steadily during the first half (upto mid-October) after which a decline in the growth rate was evident as the mean temperature reached below 18°C. In the polyculture ponds the prawns attained an average size of 10.10 ± 0.03 cm weighing 18.39 ± 0.89g (without C. carpio) and 8.4 ± 0.36 cm weighing 15.23 ± 0.36 g (with C. carpio) in 4 months and their survival rate was less than 70%. Prawns being benthic feeders utilized the leftover food (of the fishes) that settled at the bottom, therefore, saving the feed cost. It was observed that mean size of the fish attained in the polyculture practice was almost similar to that obtained in the monoculture. The ideal prawn polyculture should be practiced with fast growing compatible carps such as Rohu and grass carp. Bottom feeder carps such as Mrigal (C. mrigala) should be avoided in prawn polyculture practice as they compete with prawns in feeding.

The present study was carried out to study the feeding habits of Labeo rohita from culture ponds of Gho-Manhasa fish farm, Jammu. Monthly samples were collected from the ponds to study the gut contents. In case of L. rohita in LrfI (lowest size group) and LrfII, LrfIII 40 guts/group, LrfIV 50 guts (due to non-availability of the size categorized) and 120 guts each in case of LrfV and LrfVI (largest size group) were analysed. For every group 10 guts/month were analysed to study feeding ecology in case of L. rohita. Individual stomach fullness scale was estimated to a subjective scale, ranging from 0 (empty) to 5 (full). The results so obtained were used to compute percentage volume of food items in the gut (%V), percentage of ocurrence of guts having particular food item (%0) and Index of preponderance (IOP). The food of Labeo rohita consisted of plant (algae and macrophytes) and animal matter (protozoa, rotifers, cladocerans, copepods, molluscs, annelids and insects) besides unidentified matter (UM), sand/mud and detritus. Of the total 420 specimens analyzed, only 84 (20%) were found with empty guts and 336 (80%) were found with food components. Index of Preponderance (IOP) revealed that algae, along with protozoans, rotifers and cladocerans were the most preferred food items in the smaller size groups and marked a decline as the size of the fish increased. In the advanced stages, macrophytes, detritus and sand/mud were Found to form a major share of food. Subsequently rohu has been categorized as omnivore-planktophage in early stages of life and herbi-omnivore in adult stages.

The present study was carried out to study the feeding habits of Labeo rohita from culture ponds of Gho-Manhasa fish farm, Jammu. Monthly samples were collected from the ponds to study the gut contents. In case of L. rohita in LrfI (lowest size group) and LrfII, LrfIII 40 guts/group, LrfIV 50 guts (due to non-availability of the size categorized) and 120 guts each in case of LrfV and LrfVI (largest size group) were analysed. For every group 10 guts/month were analysed to study feeding ecology in case of L. rohita. Individual stomach fullness scale was estimated to a subjective scale, ranging from 0 (empty) to 5 (full). The results so obtained were used to compute percentage volume of food items in the gut (%V), percentage of ocurrence of guts having particular food item (%0) and Index of preponderance (IOP). The food of Labeo rohita consisted of plant (algae and macrophytes) and animal matter (protozoa, rotifers, cladocerans, copepods, molluscs, annelids and insects) besides unidentified matter (UM), sand/mud and detritus. Of the total 420 specimens analyzed, only 84 (20%) were found with empty guts and 336 (80%) were found with food components. Index of Preponderance (IOP) revealed that algae, along with protozoans, rotifers and cladocerans were the most preferred food items in the smaller size groups and marked a decline as the size of the fish increased. In the advanced stages, macrophytes, detritus and sand/mud were Found to form a major share of food. Subsequently rohu has been categorized as omnivore-planktophage in early stages of life and herbi-omnivore in adult stages.