Growth and food consumption of milkfish (Chanos chanos) during dry and wet seasons
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This study was conducted to evaluate the quality of the food consumed by the fish, to estimate the food consumption of the fish in the natural environment during the wet and dry seasons, and to determine the relationship between the growth and food intake. The milkfish fingerlings with the average weights of 4.0 g (wet season) and 9.0 g (dry season) were stocked @ 700 ha-1 in three 1000 sq. m brackishwater ponds. The unfed fish depended on the natural food alone (natural food treatment), while the fed fish were given the supplemental diets containing either 25 per cent protein and 3031 Kcal energy (natural food plus 25% protein diet) or 36 per cent protein and 3344 Kcal energy (natural food plus 36% protein diet). The food consumption increased linearly with the fish growth. Among the environmental factors measured, the salinity varied greatly between the seasons. The caloric and protein intakes for all the fish were higher during the wet season (average salinity, 22 ppt) than during the dry season (average salinity, 36 ppt). Also, the quality of food in terms of the protein and energy levels and the protein energy to total energy ratio was better in the wet than in the dry season. Based on the estimated contribution of the natural food, the rate for the supplemental feeding ranged from 2 to 4 per cent for the body weight during the wet season and from 1 to 2 per cent during the dry season. The feeding during the dry season, however, appeared to have less effect on the growth. It is recommended that the salinity should be maintained below 36 ppt for effective feeding management.
CitationSumagaysay, N. S. (1994). Growth and food consumption of milkfish (Chanos chanos) during dry and wet seasons.
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The effect of tank color and rotifer density on rotifer ingestion, growth and survival of milkfish (Chanos chanos) larvae MN Duray -
The Philippine Scientist, 1995 - San Carlos Publications, University of San CarlosThe effect of tank color on rotifer ingestion, early growth and survival of milkfish larvae was assessed. The larvae were stocked at 30/L in 200-L fiberglass tanks coated black or unpainted (tan). Larvae were fed rotifers at densities of 5, 10, and 15/ml. Growth and survival were higher in black tanks than in tan tanks. Rotifers ingested were also higher in larvae reared in black tanks. In black tanks, the survival of the larvae was enhanced at high rotifer density of 15/ml. Rotifer ingestion and growth of larvae improved at higher feeding levels.
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Aquaculture Economics and Management, 2006 - International Association of Aquaculture Economics and Management (IAAEM)Uncertainties and lack of information on milkfish product prices, along with production-related problems with inputs, generally constrain efficient resource use in milkfish grow-out operations. Milkfish growers complain of fluctuating product prices such that when output price is low, they refrain from investing in inputs and technologies recommended to boosts production. The industry wants to know the state and behavior of milkfish prices. ARIMA models showed instantaneous price relationships between monthly wholesale prices in Manila and the regional producing areas. The cross-correlations of the error terms of the ARIMA models showed that prices in Manila are related with Lucena, Dagupan, Iloilo, and Zamboanga prices, but not with Cebu. Seasonal price indexes are higher (> 1) from December to May and lower (< 1) from June to November. Milkfish grow-out operators may benefit from understanding these patterns of price movements.
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