Survey on the use of natural food and supplemental feed in commercial milkfish farms on Panay, Philippines
Abstract
This study evaluated the feed intake of the milkfish (Chanos chanos Forsskål) in commercial brackishwater ponds under different management regimes. Feed intake and growth were compared between a rather intensive culture management in a fish farm of 1 ha pond size and a semi-intensive one, with a total pond area of 30 ha. The data suggested a direct consumption of only 12 % of the supplemental feed in the intensive farm, leading to a wastage of high quality fish feed and a significantly lower specific and metabolic growth rate (P< 0.001) than in the semi-intensive system without any supplementation and only relying on abundant natural food through fertilization. These results suggest that a heavy reduction in, or even the abandonment of the use of, supplemental feed for milkfish culture would be more cost-effective.
Publisher
Stuttgart UniversitySubject
Type
Conference paperCollections
- Conference Proceedings [282]
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Conference paper
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- In Proceedings of the International Milkfish Workshop Conference, May 19-22, 1976, Tigbauan, Iloilo, Philippines, 1976 - Aquaculture Department, Southeast Asian Fisheries Development CenterIn studying the nutritional requirements of young milkfish experiments were conducted to develop a purified test diet. Mixtures of the purified constituents tested were: vitamin-free casein, vitamin-free gelatin, supplemented with L-tryptophan and L-cystine as the protein sources; shark liver oil and soybean oil as the far sources; and dextrin as the carbohydrate source. Mineral mixture and vitamin mixture were also added. The results showed that a test diet containing vitamin-free casein supplemented with L-tryptophan as the protein source, was best for the growth of young milkfish. Soybean oil was found to be a better source of fat. Vitamin mixture (4%) and mineral mixture (10%) were observed to promote growth in young milkfish. A purified test diet consisting of vitamin-free casein 60%, L-tryptophan 0.5%, soybean oil 10%, vitamin mixture 4%, mineral mixture 10%, carbohydrate and others 16% was thus suggested for young milkfish. -
Conference paper
Growth and survival of milkfish (Chanos chanos) larvae reared on artificial diets
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Conference paper
Changes in lipid and fatty acid content during early larval development of milkfish (Chanos chanos): influence of broodstock diet
- In CL Marte, GF Quinitio & AC Emata (Eds.), Proceedings of the Seminar-Workshop on Breeding and Seed Production of Cultured Finfishes in the Philippines, Tigbauan, Iloilo, Philippines, 4-5 May 1993, 1996 - Aquaculture Department, Southeast Asian Fisheries Development CenterThe influence of amount and type of lipid given to milkfish broodstock by developing larvae was investigated by feeding broodstock commercial diets that differed in lipid content and composition. The two commercial feeds used had the following proximate composition: RFP - 28.16% crude protein, 2.40% crude fat, 7.58% crude fiber, 53.94% N-free extract; RCP - 43.28% crude protein, 4.58% crude fat, 6.18% crude fiber, 37.0% N-free extract. The lipid content and fatty acid composition of spawned milkfish eggs reflected that of the broodstock feed. Percent lipid in egg from broodstock fed RFP and RCP dropped by 22.5% and 26.9% in newly-hatched larvae and by 53.0% and 65.0% in day 2 larvae (>90% yolk resorbed), respectively. Decreases in total PUFA and increase in monoenoic fatty acids during yolk resorption indicate that milkfish as in other marine fishes utilize PUFA during early larval development. While differences in rate of utilization of individual n-3 and n-6 FA in two groups of larvae seem to be influenced by levels of the fatty acids in eggs, the influence of other nutrients on fatty acid utilization need to be investigated.
