INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 8, ISSUE 11, NOVEMBER 2019 ISSN 2277-8616 Comparative Study on Growth Performance of Poecilia Sphenops (Valenciennes, 1846) Under Different salinity and Different diets Anandakumar Arunkumar, Gnanakkan Ananthan, Rajaram Murugan Abstract: Poecilia sphenops (Molly) is a commercially important ornamental fish which is popular among new hobbyist and breeders as they are easy to groom and breed. Current research was done to study influence of salinity of water and different diets ((i) Chironomus larvae, (ii) Cyclops, (iii) Artemia, (iv) Daphnia, (v) Commercial feed) on the growth performance and survival of molly fish. Maximum length gain was observed in fish fed daphnia grown in saline water followed by fish fed with artemia diet and poor growth performance was observed fish grown in fresh water fed with pellets. Highest Weight gain is observed in fish grown in saline water and fed with daphnia, followed by artemia diet, Poor weight gain is observed in fish gown in freshwater fed with pellets. Specific growth rate was higher in fish grown in saline water fed with daphnia. SGR was lower in fish grown in freshwater fed with pellets. Keywords: Poecilia sphenops, artemia, daphnia, SGR. ———————————————————— 1. INTRODUCTION Mollies are omnivores, feeding primarily on algae and other The unique feature of the ornamental fishsh trade is that plant materials, but aquatic invertebrates including a variety fish are sold by price per fish than by weight. The estimated of zoobenthos and detritivores such as mosquito larvae, global trade is US $3 billion in retail and US $900 million in contribute to its diet. They also feed on bloodworms. wholesale (FAO 2006). Poeciliids are listed among the top Though Poecilia sphenops occurs in groups, feeding occurs 10 species of ornamental fishes imported into the USA. In independently (Wischnath, 1993). The short-finned molly India poeciliids account for fifty percent of the market share has many artificially selected varieties sold commercially. in ornamental fishes (Mahapatra et al., 2000, Naturally occurring populations of the short-finned molly Ramachandran 2002). Wild fishes of the genus Poecilia may contribute to control mosquito populations by feeding (guppies and mollies) are generally found in fresh- and on the larvae and pupae of these pests (Schoenherr, 1979). brackish water bodies such as streams, rivers, ponds, and Salt is conventionally added to molly tanks to induce estuaries (Nordlie et al., 1992). Poecilia sphenops are breeding (Whitern 1983). Many researchers demonstrated commonly known as molly it is popular among the the remarkable tolerance of poeciliid fishes in wideranges of ornamental fish hobbyist as it is very easy to grow and temperature (Bennett and Beitinger, 1997) and salinity breed. It inhabits mainly fresh water systems, in shallow (Kristensen, 1969; Nordlie and Mirandi, 1996; Haney and areas, spending little time in coastal brackish waters Walsh, 2003). Nordlie et al., (1992) reported the occurrence (Wischnath, 1993) before returning to freshwater biotopes. of wild poeciliid fishes (guppies and mollies) in fresh water The wild variety of the common or short-finned molly has and brackish waters. However, most aquarium hobbyists dull silvery colouration, with dispersed black dots on its skin and ornamental fish farmers keep and breed sailfin mollies and a bright yellow fringe on the ends of its rounded dorsal in fresh water (Ramachandran, 2002; Ghosh et al.,2003). and caudal fins. Individuals of this species exhibit wide Current study deals on comparison of growth performance, ranges of colour variation that mainly incorporates silver, breeding performance, and Survival rate of molly fish in salt black and yellow-orange. The body is oblong with a round water and fresh water fed on different diet (i) chironomus caudal peduncle and a small dorso-ventrally flattened head larvae (ii) Cyclops (iii) Artemia (iv) Daphnia (v) Commercial with protruding jaws that function as a scraping tool, ideal feed. for rasping algae from benthic surfaces. Its mouth also possesses many rows of very small teeth, with the outer 2. MATERIALS AND METHODS row being the largest and reducing in size with each Even sized new born fry of Poecilia sphenops were successive row. Poecilia sphenops displays sexual obtained from ornamental farm in Madurai. Fish were dimorphism whereby males are smaller (8cm compared to packed in oxygenated plastic bags and transported to 12cm of females) and more colourful, particularly males’ hatchery in Centre of Advanced study in marine biology, larger caudal fins (Mills and Vevers, 1982). Annamalai University, Portonovo. Fish were stocked in 2000 litre Fibre reinforced plastic tanks with proper ______________________ aeration, fitted with filtration system and initially fed commercial feed (Aquatic remedies). Fish was acclimatized CAS in Marine Biology, Faculty of Marine Sciences, to both freshwater and marine water for 30 days, after Annamalai University, Parangipettai, India acclimatization the fish were separated into eight batches of Corresponding Author which four batches were cultured in fresh water and Gnanakkan Ananthan remaining four batches cultured in marine water, each CAS in Marine Biology, Faculty of Marine Sciences, batch has 20 fry. Four batches of both fresh and marine Annamalai University, Parangipettai, India water received different dietary treatments (i) chironomus larvae, (ii) Cyclops, (iii) Artemia, (iv) Daphnia, (v) Commercial feed. Fish were reared for a period of 4 2842 IJSTR©2019 www.ijstr.org INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 8, ISSUE 11, NOVEMBER 2019 ISSN 2277-8616 months, during the culture period proper aeration salinity tolerance of poecilid fish was done by several provided,water exchange was done once in a week, investigators and several investigations proved the wide uneaten feed and excretory waste were removed regularly range of salinity tolerance of poecilid fish (Kristensen, 1969, through siphoning and the dead fish were also removed Nordlie et al., 1992, Arai et al.,1998; Limia melanonotata, from the tank. Water sampling done in every tank Haney and Walsh,2003, Kumaraguru vasagam et al.,2005). periodically. At the conclusion of the growth trial, the mean Plenty of work recorded the wild occurrence of P. latipinna weight gain and survival of each salinity treatment were in fresh and salt water environs such as rivers, ponds, determined. Analyzed parameters included: feed lakes, mangrove swamps, coastal marshes, estuaries, and conversion ratio (FCR) = dry feed offered/weight gain and back waters (Peterson, 1990; Schlupp et al., 1992). In the specific growth rate (SGR) = [(lnWt – lnWi) x 100]/T, where current study salinity significantlyInfluenced the growth Wt = mean final weight, Wi = mean initial weight and T = parameter of molly fish comparatively higher growth total experimental days. performance was observed in fish grown in estuarine water and poor growth performance observed in fish grown in 3. RESULTS fresh water. Similarly, live feed influenced the growth Growth indices performance of molly fish specifically fish fed daphnia had The growth parameters of individual experimental setup are maximum growth performance and fish fed pellet feed had shown in Table 1&2. Specific growth rate and survival rate poor growth performance. The cladocerans are considered of different experiment are graphically represented in figure to be suitable live feed for fish larvae and they were mass 1 and 2. Different dietary and salinity treatment significantly cultured successfully by many investigators, using different influenced the growth indices of the fish. Maximum length cheap organic waste products (Srivastava et al.,2006, Altaff gain was observed in fish fed daphnia grown in saline water et al.,2010). Highest survival rate was observed in fish (5.0 ± 0.1 cm) followed by fish fed with artemia diet (4.3 ± grown in estuarine water and fed with daphnia; Lower 0.3 cm) and poor gowth performance was observed in fish survival rate is observed in fish grown in fresh water fed grown in fresh water fed with pellets (1.8 ± 0.4 cm) . with pellets. Previously (V. Sumithra et al.,2013) reported Highest Weight gain is observed in fish grown in saline that that feeding the molly fish fries with mixed feed of water and fed with daphnia (4.22 ± 0.1 gm), followed by suitable sized rotifer, copepod and cladoceran is artemia diet (3.84 ± 0.3 gm), Poor weight gain is observed advantageous for the survival of fish since a variety of size in fish gown in freshwater fed with pellets (1.05 ± 0.3 gm). range of nauplii, copepods and neonates of zooplankton to Specific growth rate was higher in fish grown in saline water adults will be available as larval feed. fed with daphnia (7.03 ± 01) SGR was lower in fish grown in freshwater fed with pellets. 6. CONCLUSION Current study proves that molly fish P. sphenops can be 4. SURVIVAL successfully cultured in saline water, and the present study Similar to growth performance survival rate is also suggests feeding molly fish with live feed especially influenced by diet and salinity maximum survival rate of Daphnia as they are known to increase the growth (98%) observed in fish cultured in saline water fed with performance such as length gain, weight gain, specific Daphnia and lower survival observed in fish grown in fresh growth rate, and survival rate. But Still nutritional value of water fed with pellets ( 77%). individual