The fry and fingerling industry of the milkfish (Chanos chanos Forskal) in the Philippines is alleged to suffer from certain imperfections. Primary among these are an annual shortage of catch necessary to meet the stocking requirements of the 176,000 ha of fishponds; high fry mortality rates during transp0rt;failure of the pricing system to perform its spatial and form allocative functions; and exploitation of fry gatherers and pond operators by middlemen and nursery pond operators who form the core around which the whole fry and fingerling industry has developed. These alleged imperfections provide the rationale for various government policies affecting the fry and fingerling industry. This study indicates a higher level of industry performance than hitherto supposed. In 1974, an estimated 1.35 billion fry were caught, adequate to meet annual stocking requirements. Allegations of fry shortage were based on simultaneous underestimation of catch and overestimation of stocking requirements, and were traced to temporary price increases resulting from expanded fishpen area, which subsequently declined. Fry storage and transport mortality rates of 8.7% and 6.6%, respectively, compared with a mortality rate of 54% during rearing, indicated that major technical inefficiencies arise in fishponds rather than in the distribution system. Of every 100 fry caught, 38 are harvested at marketable size. Monthly average fry prices among 17 major trading regions were significantly correlated, indicating a high level of information flow in the industry. An examination of the concession system which restricts first sale opportunities of gatherers indicated that concessionaires are unable to capture their full monopsony advantage due to the "competitive fringe" of smugglers. Rather than exploitation, the concession system is a form of indirect municipal tax on fry gatherers. Since the fry industry is a 57-million-peso-per-year industry upon which approximately 170,000 people directly and indirectly depend, it is suggested that the location of future milkfish hatcheries and timing of production be planned such that they complement rather than displace the natural fry fishery and distribution system.

This chapter aims to introduce concepts and methods in doing economic analysis applicable in aquaculture in general with emphasis in feed production and feeding in aquaculture farms. This chapter discusses the following topics: cost of producing feeds; simple single-input (feeds) and single output (fish) production function; indices for measuring economic efficiency of feeds; the least-cost combination; and linear programming as used in the allocation of limited resources such as feed ingredients that will meet the nutritional requirements of the fish.

This chapter discusses how to evaluate feedstuffs and feeds. The results of feed evaluation will be used to ensure the production of high quality feeds for fish, crustaceans, and shellfish.

The development of a feed that is both effective and economical for an aquaculture species in all its life stages is a continuous effort. Aquafeed development started when natural food sources in culture systems became inadequate and had to be supplemented with prepared feed. As fish stocking densities in culture increase, supplemental feeding is no longer sufficient. A complete feed that contains all the necessary nutrients in sufficient amounts to bring about good growth, survival, and reproduction is needed. Feed ingredients generally come from animal or plant sources and some are by-products of the food industry. There is no single feed ingredient or feedstuff that contains all the nutrients in adequate amounts. Thus, different feed ingredients are combined to make a feed that has the desired composition and nutrient levels. In combining various feed ingredients, it is important to know how much of each feed ingredient should be used to produce a cost-effective aquafeed. With the growth and expansion of aquaculture into a major industry, several fish species are being cultured; thus, the development of more efficient aquafeed formulations should continue. In developing cost-effective formulated diets, many important factors have to be considered. This chapter discusses these factors and the mathematical calculations in formulating a feed. It aims to enable students to formulate diets using purified and practical feed ingredients, and also to formulate effective supplemental and complete diets for aquaculture species.

This section discusses the macro, micro, and trace minerals; their physiologic functions; and deficiency signs and symptoms. It also gives a summary of the mineral functions and mineral requirements of fishes and shrimp.

After studying this section, the reader should be able to differentiate the forms of energy and their measurement. Understand dietary energy metabolism, the energy balance equation and factors that influence dietary energy requirement of fish; and understand the significance of optimal protein to non-protein energy in fish diets.

The objective of this section is to acquaint the reader about common fatty acids, their nomenclature and formulas, and differentiate between saturated and unsaturated fatty acids; to know how environmental factors (temperature, salinity, diet) influence the fatty acid composition of fish; the mechanisms of fatty acid biosynthesis and oxidation, and factors that favor fatty acid biosynthesis and oxidation; the effects of lipid peroxidation and the function of antioxidants; and to understand the importance of fatty acid profiles in fish nutrition, and differences in the essential fatty acid requirements of warmwater and coldwater fishes.

This practical book on the seaweeds of Panay, Philippines, acquaints and provides information to members of the academe and research institutions, policy makers, fishermen and businessmen regarding the taxonomy, distribution, ecology and economic importance of these resources. It consists of 4 major parts: (1) Introduction, which reviews the literature, habitat, distribution, morphological structure and reproduction; 2) Classification, which describes the classes to which the seaweeds generally belong; 3) Collection and preservation, which explains the procedure used in treatment of specimens; and, 4) Taxonomic list. A glossary is included, covering technical terms used. All species listed and described in this book are macrobenthic and were collected in Panay and Guimaras Islands.