Effect of formulated feed on weaning of mud crab (Scylla Serrata) in floating cellular cages

Abstract- In the present study, a total 250 crablets were collected from hatchery and weaning of mud crablets in a two type of enclosures with newly formulated feed in two different form, pellets and flakes with control. The seeds are acclimatized and stocked in the floating farm with individual cellular cages in respective treatments. All crablets were fed @ 10% of body weight divided into two times in a day, at morning and evening for period of 90 days. The crablets were measured for their morphometric characters on every 10 days of intervals and calculated the growth parameters and biomass. The water quality parameters were recorded in optimum level from the culture site during the present study did not fluctuate much. Proximate composition of formulated feed with a crude protein content of 41.48 %, crude lipid of 8.10%, Crude fibre of 4.06%, nitrogen free extract of 25.98% and ash content of 12.49% with almost 8% moisture was used in the experiment. Highest survival rate was observed in Treatment I (98.2 %) and the lowest survival rate was in Control (92.0%).Carapace width-weight relationship showed with an isomeric growth and a highly significant correlation between carapace width and weight in all the treatments and control.The percentage of weight gain was showed an increasing trend initially upto 30 DOC and then gradual decrease during the period of experiment. The highest value was recorded in Treatment III and I.The specific growth rate values of all the parameters also showed this increasing trend initially and then decreases during the period of study. Similarly, the daily growth rates of carapace width and carapace length showed an increasing trend. Whereas, in the case of total weight, it was showed an increasing trend with increase in DOC.Feed conversion ratio (FCR) was calculated were showed a better performance in the treatments (Treatment I, II, III & IV), in which self-formulated feeds (Pellet feed and flakes feed) were trialed than that of the control (fed with commercial shrimp pellet feed).Among the treatments, the best feed conversion ratio was recorded in Treatment I with an average ratio of 2.2 during the study. A comparison of performance was also carried out for the pellets and flakes feed with control showed that pellet feed is better than flakes as evident FCR values.