Digestibility and Nitrogen Balance of Diets That Include Marine Fish Meal, Catfish (Pangasius Hypophthalmus) By-Product Meal and Silage, And Processing Waste Water in Growing Pigs (Report‪)‬

INTRODUCTION Pig production is the dominant form of livestock production in Vietnam and accounts for around 80% of the total meat consumption of the country (Livestock Department, 2006). Conventional protein supplements for commercial pigs, such as fish meal and soya bean meal have become relatively expensive. The resulting imbalance between feed and animal production prices has reduced profitability for pig farmers. Catfish production for export has increased rapidly in recent years in the Mekong Delta, and significant amounts of head, bone, scrap meat and skin by-products (710-900 tons/d; Thuy et al., 2007) are produced from fillet processing. By-products account for approximately 65% of the whole catfish (Nortvedt, 2007). Catfish by-product meal (CBM), ensiled by-product (CBE) and processing waste water (WWB) from the CBM processing are potentially valuable alternative protein sources in pig rations to conventional protein supplements such as soya bean meal and fish meal. However, there are no published data on the digestibility of these by-products, especially ileal amino acid digestibility in pigs. The aim of this study was to determine the nitrogen retention and the apparent digestibility of dietary components and amino acids in diets containing catfish by-product meal, ensiled by-product and processing waste water resulting from catfish processing.