ln silico comparison of the technical and economie impacts of two-phase, multiphase and precision feeding strategies on pig populations of three sexual types
Comparaison in silico de l’impact technico-économique de stratégies alimentaires biphase, multiphase et de précision sur des populations de trois types sexuels de porcs
Résumé
The aim of this study was to compare in silico the impact of two-phase, multiphase and precision feeding strategies on the performances of three sexual types of growing pigs. individual profiles of 26 femaies, 19 entire males and 20 barrows (Large White x Landrace) x Piétrain were obtained using inraPorc® from experimental growth and feed intake data. The mean profile per sex was used to generate 10 virtual populations (200 pigs each) per sex. lndividual performances were simulated using lnraPorc® for three feeding strategies: two-phase (2P), diets supplying 9.70 MJ NE/kg and 0.85 % digestible lysine (Lysd) (70 days of age to a mean body weight (BW) of 65 kg) and 9.61 MJ NE/kg and 0.75% Lysd (65 kg BW until slaughter); multiphase by daily mix of diet El (1.08% Lysd) and diet E2 (0.36% Lysd) (both 9.70 MJ NE/kg), adapted by sex to meet the Lysd requirement of 80% of the population (MP); precision feeding (PF) with daily adjustment of Lysd supply to individual requirement. Simulations were performed with ad libitum feeding or ad libitum until a maximum allowance of 24 MJ/d. Pe rformance was calculated from 70 days of age to slaughter, defined in two departures at 115 kg mean BW. Feed restriction improved growth efficiency and margin over feed cost, and reduced nitrogen output especially in barrows. Compared to 2P, MP improved growth efficiency and BW variation at slaughter especially for entire males. Compared to MP, PF also improved these criteria and margin, and reduced nitrogen output.