Use of the ncpig swine growth model for heat stress assessment

摘要

Research to develop or identify the most appropriate control variables for optimization of swine growth response under heat stress is described. Comparisions among several potential predictor variables are presented including maximum ambient temperature, THI (temperature-humidity index), 12-36 hour time-integrated temperature (TIV), and daily degree-hours above a prescribed base. Responses were simulated using the NCPIG model for high-lean-growth finishing pigs in the 95-105 kg range under summer conditions. A statistical assessment of predictive capacity of the selected variables indicated Tmax and three TIV variables provided an input set yielding two significant principal components that explained 98.6 percent of variance in growth response.