Growth performance of Indian major carps on different feeds and cost-benefit analysis

Abstract

A study was conducted to establish an optimal methods under two feeding regime (poultry waste and supplementary) for the culture of Indian major carps by comparing the growth patterns and to develop a cost efficient feed and feeding technique through cost benefit analysis for future use in Bangladesh. Static 5.00 mg/L dissolved oxygen content was the remarkable observation during the investigation period in both study ponds except March’14 at treatment I and treatment II. The ponds were slightly alkaline with pH values ranged from 6-7 Hardness, alkalinity and ammonia showed narrow difference in their mean value. The average survival rate of different species was found satisfactory and comparatively higher in treatment I and were significantly different from treatment II .The highest survival rate was 92.67% for Labeo rohita and the lowest was 87.66% for Cirrhinus mrigala. In treatment II, the range was 76.33% to 84.66%, the highest survival rate was 84.66% for L. rohita, and the lowest was 76.33% in C. mrigala. The present study indicated a non significant difference in the growth rate among the individual species in treatment I and II. Highest SGR was calculated as 3.28% in C. catla in treatment I and lowest 1.47% in C. mrigala in treatment II. The eighteen months investigation showed the gross final weight gain were for Labeo rohita, Catla catla and Cirrhinus mrigala were 1520gm., 1860gm. and 1470gm, in treatment I and 870gm., 920gm. and 855gm. at treatment II, respectively. Monthly mean growth gain (gm.) of the species were 92.04±75.38, 100.06±93.79 and 79.41±75.51 at treatment I and 45.96±58.19, 47.61±52.09 and 61.94±97.07 at treatment II. The main growth performance factor length-weight relationship was calculated with the average data based on measurements of 50 fishes of each species and observed a significant difference between two treatment groups. Monthly mean growth of L. rohita, C. catla and C. mrigala showed increased rates with onset of rainy period and decreased growth and decreased rates during the winter period. Most of the months showed significant correlation. All the species showed allometric growth patterns in two feeding regimes with different developmental variances depending on influence of physicochemical and biological influences. vi Statistically all independent predictor variables viz. Temperature °C, DO mg/L, CO2 mg/L, pH, Hardness, Alkalinity mg/L, NH3 mg/L, Premix vitamin (kg), Fishmeal (kg) in treatment I and temperature °C, CO2 mg/L, pH, Hardness, NH3 mg/L, Alkalinity mg/L in treatment II, explains 79.6%, 81% and 80.60% and 29.39%, 29.60% and 29.39 effect on length development variance of L. rohita, C. catla and C. mrigala in treatment I and treatment II, respectively, which are not significant as indicated by 2.73, 2.09 and 2,90 F values and 0.098b, 0.080b, 0.085b P values and 0.680, 0.701 and 0.649 F values and 0.664a, 0.656a and 0.664 P values. The same predictor explains 89.20%, 87.60%, 89.20% and 39.00%, 39.30%,41.70% effect on growth development variance of L. rohita, C. catla and C. mrigala in treatment I and treatment II, respectively, which are not significant as indicated by ANOVA F values -5.78, 4, 92, 5.80 and 0.050a, 0.023a, 0.15a P values and 1.02 ,0.87, 1.80 F values and 0.46b, 0.54b, 0.30b P values. Biological variable planktons viz. Chlorophyceae, Cyanophyceae, Euglenophyceae, Rotifera, Cladocera, Copepoda, Ostracoda, Nauplius as predictor explains 40.40%, 40.570% and 40.40% effect on variance in length development of L. rohita, C. catla and C. mrigala which were not significant as indicated by ANOVA F values 0.678, 0.682 and 0.677 and P values 0.702b, 0.700b and 0.730b in treatment I. On the other hand 51.30%, 49.70%, 52.10% effect on variance in length development of L. rohita, C. catla and C. mrigala, which were not significant as indicated by ANOVA F values 0.678, 0.682 and 0.677 and P values 0.702b, 0.700b and 0.730b in treatment II. In the same way biological variable as predictor explains 42.70%, 42.80% and 42.90% effect on variance in weight development of L. rohita, C. catla and C. mrigala which were not significant as indicated by ANOVA F values 0.747, 0.747, 0.759 and P values 0.655b, 0.655b, 0.653b in treatment I. A little higher 51.30%, 49.70%, 52.10% effect on variance in weight development of designated species, which were not significant as indicated by ANOVA F values 0.678, 0.682 and 0.677 and P values 0.702b, 0.700b and 0.730b in treatment II. Standardized coefficient values indicates that none of the physicochemical and biological plankton variables, contributes the prediction of length and weight development of L. rohita, vii C. catla and C. mrigala and explains an equal non-significant combined influence on the length and weight development of species under investigation. Biological ecto and endo parasitic variables showed more less same prevalence and infestation with seasonal variation and host selection in I and II Treatment group. Total 8.0% and 24.0% L. rohita, C. catla and C. mrigala faced the paroasitic death during Winter, 10.0% and 30.0% faced during Summer and 16.0% and 38.7% during Monsoon in treatment I and in treatment II, respectively and showed significant (p<0.05) correlation between the two groups. The study showed that C. catla made the highest contribution to the total yield in two treatments. Contribution of L. rohita was about 32.84% in treatment I and 34.74% in treatment II. C. catla Contributed 35.83% in treatment I and 33.77% in treatment II. C. mrigala was found to contribute 31.31% in treatment I and 31.47% in treatment II. Gross production of individual species of fish was calculated from the average final weight multiplied by the actual numbers of fish harvested. In treatment I, net weight was calculated 407.56, 490.14 and 372.21 in L. rohita, C. catla and C. mrigala and 198.15, 204.06 and 181.39 in L. rohita, C. catla and C. mrigala in treatment II. It is obtained from the present investigation that total production of treatment I and treatment II were 1269.91 kg. and 583.60 kg. Unpaired t-value at 0.001 levels indicate final production of L. rohita, C. catla and C. mrigala of two groups in feed feeding system are positively correlated without influence of feed. The key financial and economic indication of two feeding regime ponds. The cost for the production was 2,16,471 Tk. in treatment I and 39,952 Tk. in treatment II. Net return was 3,95,677 Tk. and 1,66,582 Tk. in treatment I and treatment II, respectively. Calculated total net return of profit was 1,79,206 Tk. in treatment I and 1,26,630 Tk. in treatment II. Percentage of profit was 83 % in treatment I and 317% in treatment II. Cost and benefit ratio was 121:100 in treatment I and 32: 100 in treatment II. Cost profit ratio and benefit cost ratio were positively significant (P=0.05 and P=0.001). The profit function analysis clearly showed that the production and profitability of the system can be increased further by judicious application of fertilizer and feed. Other variables like viii labour showed negative returns and hence farmers have to carefully manage labour inputs. With the availability of the large amount of feed ingredients in Bangladesh, significant improvements in fish production can be achieved. It is likely that the current level of profitability would encourage more land to be converted to aquaculture, particularly by using the vast amount of waste land available in Bangladesh. It was also observed that there were many possibilities to increase production further by introducing and adopting better management practices.