Nonruminant Nutrition: Feed Ingredients/Feed Additives

Marine algae have recently emerged as a new exciting source of biofuel. Our objective was to determine effect of supplemental defatted algal biomass from biofuel production on biochemical indicators of protein metabolism in plasma of weanling pigs. A total of 27 weanling pigs (BW = 10.69 ± 0.22 kg) were divided into 3 groups (n = 9/group), and fed a corn-soybean meal basal diet (BD), the BD plus 6.6% whole algal meal, or the BD plus 7.2% defatted algal meal (provided by Cellana, Kailua-Kona, HI) for 6 wk. Plasma urea nitrogen concentration, an indicator of dietary protein utilization efficiency, was not affected by the treatments as the 3 groups of pigs had similar values (mg/L) at Wk 3 (112.4 ± 9.4, 93.3 ± 11.0, and 102.1 ± 9.1) and Wk 6 (163.0 ± 22.1, 170.8 ± 14.7, and 155.9 ± 16.9). There was no group difference in plasma alanine aminotransferase or alkaline phosphatase activity at either time point. Ultrasound scan of vertebral fat and muscle depth of individual pigs at Wk 3 and Wk 6 predicted similar body lean yield (%) among all the 3 groups (Wk 3: 50.7 ± 0.2, 50.8 ± 0.2, and 50.7 ± 0.1; Wk 6: 52.2 ± 0.2, 52.1 ± 0.4, and 52.4 ± 0.1). In conclusion, adding 6.6% of whole algal meal or 7.2% of defatted algal meal into a corn-soy basal diet for weanling pigs effectively replaced the same amount of soybean meal without adverse effect on the biochemical indicators of protein metabolism or health.