Submitted to: International Poultry Forum Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 11/12/2005
Publication Date: 1/23/2006
Citation: Adedokun, S.A., Powers,W., Angel, R. Mitchell, A., Applegate, R.J. 2006. Determination of nutrient mass balance in turkeys [abstract]. International Poultry Scientific Forum. M34.
Technical Abstract: Apparent phosphorus (P) and nitrogen (N) retention and excretion were determined for turkeys fed two diets at three different ages via mass balance from feed intake, carcass retention, and litter mass and composition. The two diets consisted of a typical industry diet (I) and a low P + 600 U/kg phytase (LP) diet. The non-phytin P concentration of the diet was 0.70, 0.65, 0.60, 0.55, 0.45, or 0.40% for I diets and 0.52, 0.42, 0.34, 0.30, 0.24, or 0.20%, for LP diets from 0-3, 3-6, 6-9, 9-12, 12-15, and 15-18 wk of age, respectively (12 replicates with five birds per pen). Birds from four pens per diet were weighed and killed at 12, 15, and 18 wk of age for nutrient retention (from whole carcasses) and excretion (from litter) determinations. Diet did not affect BW or feed intake from 12 to 18 wk of age (18 wk BW = 16.04 kg). The mass of P excreted at 12, 15, and 18 wk of age was 37, 46, and 40% more for birds fed the I diets when compared to birds fed the LP diets. Phosphorus retained as percentage of P consumed was greater at 12, 15, and 18 wk for birds fed the LP diets (67.0, 63.8, and 53.8%) than for birds fed the I diets (47.3, 44.0, and 32.8%; P < 0.05). The difference between P excretion as calculated from litter compared with feed intake less carcass retention was less than 5% at 18 wk. Birds fed the I diets had greater (P < 0.05) N excretion (in litter) and N retention (in carcasses) at 15 wk (P < 0.05). Total excreta production at 18 wk was not significantly different between the two treatments and averaged 12.2 kg. While there were no differences in BW, N excretion (g) and DM excretion (kg), P excretion (intake – carcass) was 201.3 g and 94.6 g, respectively for birds fed the I and LP diets. Additionally, with an 18 wk average litter DM of 78.0% the calculated N volatilization at 18 wk was 427 and 405 g/bird for birds fed the I and LP diets, respectively (40 and 37% of excreted N). Excretion, mass balance, nitrogen phosphorus turkey