Influence of varying the level of fat and fermentable fibre through the inclusion of by-products from the food industry in growing pig diets on slurry characteristics, ammonia and methane emission

Autores UPV
Año
CONGRESO Influence of varying the level of fat and fermentable fibre through the inclusion of by-products from the food industry in growing pig diets on slurry characteristics, ammonia and methane emission

Abstract

The effect of including a partially indigestible fat source (calcium soap of palm fatty acids distillate; CSP), alone or in combination with orange pulp (OP) in growing pig diets on slurry characteristics and ammonia (NH3) and methane (CH4) emissions was studied. Thirty pigs (58.0±7.99 kg) were fed 5 diets, a C diet based on wheat, barley and soybean meal, two diets with increasing inclusion levels of CSP (35 g/kg and 70 g/kg) and two diets including 200 g/kg of OP at each level of fat supplementation. After 14 days of adaptation, slurry excretion and composition was measured for 3 consecutive days. Additionally, the potential NH3 emissions and biochemical CH4 potential (B0) from slurry were measured using in vitro methodologies. The amount of slurry excreted was not affected by the level of CSP or the inclusion of OP. The measured initial slurry characteristics did not differ ignificantly among treatments, except for volatile fatty acids that increased with CSP addition. Ammonia emission from slurry (g NH3/kg slurry) was lower in diets formulated with higher levels of CSP and no different in diets including OP compared to those without OP. A trend for an interaction (P<0.10) was observed for NH3 emission indicating that the inclusion of OP reduced NH3 emission in diets with a moderate CSP content (35 g/kg) but not in diets with a high CSP content (70 g/kg). Regarding CH4, B0 and the CH4 produced per animal and day increased (P<0.05) with the level of CSP in diets and tended (P<0.10) to increase with the inclusion of OP. Therefore, the dietary modifications studied lead to differences on NH3 and CH4 emissions from slurry. A potential interaction between the level of fat and the inclusion of OP on NH3 emissions has been detected, whereas only fat inclusion in diets increased potential CH4 emissions.