Seafood processing wastes ensiled with straw: utilization and intake by sheep

Abstract

Ensiled mixtures of seafood processing wastes and wheat straw were evaluated. Thirty-six crossbred wethers (average BW = 34 kg) were fed 1) a basal diet (hay and concentrate) alone, or a 1:1 ratio (DM basis) of basal and 2) ensiled fish waste plus straw (70:30, wet basis), 3) ensiled fish waste and straw (51:49), 4) ensiled crab waste plus straw (60:40), 5) ensiled crab waste plus straw (40:60), or 6) ensiled wheat straw (50% moisture). Dry molasses (5%) was included in all ensiled mixtures, and glacial acetic acid (16% vol/wt) was added to the crab waste mixtures. Among diets containing ensiled fish waste, DM digestibility was greater (P less than .01) for the diet containing silate with 70% fish waste than the diet containing 51% fish waste. There was no difference (P greater than .05) in DM digestibility between the two crab waste silages. Apparent digestibility of CP was greater (P less than .01) for diets containing fish than for those containing crab waste. Nitrogen retention (g/d) was positive for sheep receiving all diets but not different among treatments. Apparent absorption of P (g/d) was greater (P less than .01) by sheep fed fish waste silage diets than by those fed crab waste silage diets. Among seafood silages, DMI was greater (P less than .01) for sheep consuming the 60:40 than for those consuming the 40:60 crab waste silage diet and less (P less than .01) for sheep fed the 70:30 than for those fed the 51:49 fish waste silage diet. Seafood processing wastes potentially are valuable to ensile with crop residues for use as ruminant feedstuffs.