Table II.

Association between in-transit loss^a of the market pigs, temperature, and relative humidity

Fixed effect	IRR	sx̄	P-value
Intercept	0.00	0.20	< 0.001
Temperature 17°C to < 21°C	1.66	0.11	< 0.001
Temperature 21°C to < 25°C	1.41	0.08	< 0.001
Temperature 25°C to < 28°C	1.30	0.07	< 0.001
Temperature 28°C to 34.2°C	2.23	0.07	< 0.001
Humidity/10	1.04	0.02	0.04
Random effect	Variation	sx̄	P-value
Producerb	1.18	0.09	< 0.001
Transporterb	0.27	0.09	< 0.001
Error term	0.84	0.01	< 0.001

s_x̄ — standard error of the mean.

^aMeasured as mortality rate for transported pigs per producer per day with the use of a negative binomial linear effects model. The association was measured as an incidence rate ratio (IRR) based on a Poisson general linear mixed model, with IRR indicating the number of times the incidence rate of in-transit death increased for a temperature range compared with the range below it. N = 13 590 pigs marketed.

^bIncluded in the model as random variables.