PS5-9. Digestible and Metabolizable Energy Concentrations of Various Sources of Fish Meal Fed to Nursery Pigs

An accurate determination of energy concentrations in feed ingredients is crucial for precise swine feed formulation. Fish meal (FM) is one of the most widely used ingredients for nursery pigs. Energy values of FM vary depending on the fish species and manufacturing processes. The present experiment aimed to determine the digestible energy (DE) and metabolizable energy (ME) concentrations in 5 sources of FM originating from the Republic of Korea [FM-KR1; 54.8% crude protein (CP) and 12.6% ether extract (EE) and FM-KR2 67.2% CP and 10.6% EE], Vietnam (FM-VN; 60.6% CP and 6.9% EE), Chile (FM-CL; 71.1% CP and 9.7% EE), and Norway (FM-NO; 69.5% CP and 10.2% EE). Twelve barrows with an initial body weight of 11.4 kg (standard deviation = 0.9) were individually housed in metabolism crates. A replicated 6 × 4 incomplete Latin square design with 12 animals, 6 experimental diets, and 4 periods was employed to obtain 8 observations for each FM source. The basal diet consisted of 96.6% corn as the sole source of energy. Five experimental diets were formulated by replacing 23.0% of the corn with FM. Each period consisted of a 5-d adaptation period and a 4-d collection period. The marker-to-marker procedure was used for the quantitative collection of feces and urine. Chromic oxide was added to the morning meal on d 6 and 10 as an indigestible marker. The difference procedure was employed to calculate the DE and ME values of each FM source. The DE and ME concentrations in FM-KR2 (3,968 and 3,655 kcal/kg), FM-CL (4,212 and 3,929 kcal/kg), and FM-NO (4,222 and 3,900 kcal/kg) were greater than (P < 0.05) those in FM-KR1 (3,282 and 2,958 kcal/kg) and FM-VN (3,525 and 3,171 kcal/kg). The DE:gross energy (GE) and ME:GE in FM-NO (0.907 and 0.838) were greater (P < 0.05) than those in FM-KR1 (0.727 and 0.655), FM-VN (0.826 and 0.743), FM-KR2 (0.798 and 0.735). The ME:DE in FM-CL (0.933) was greater (P < 0.05) than those in FM-KR1 (0.901) and FM-VN (0.901) but did not differ from FM-KR2 (0.921) or FM-NO (0.923). Taken together, FM-KR2, FM-CL, and FM-NO had greater DE and ME concentrations than FM-KR1 and FM-VN. The DE:GE and ME:GE in FM-KR1 were the lowest among the FM sources. The ME:DE in FM-KR2, FM-CL, and FM-NO was greater than those in FM-KR1 and FM-VN.