7 Effect of piglet birth weight and drying on post-natal changes in rectal temperature.

The objective of this study was to evaluate the effects of piglet birth weight and drying piglets at birth on post-natal rectal temperatures using a CRD with 2 treatments: 1) Drying (not dried vs. dried at birth with a desiccant); 2) Birth weight [4 within-litter birth weight quartiles (Q1: 1.13 ± 0.33 kg, Q2: 1.43 ± 0.28 kg, Q3: 1.62 ± 0.28 kg, Q4: 1.81 ± 0.28 kg)]. Sows (26) and litters (281 piglets) were randomly allotted to drying treatment and were housed in farrowing crates with a heat lamp; room temperature was set at 22.8°C. Piglets were weighed at birth and rectal temperature measured at 0, 15, 30, 45, 60, 90, 120, 180, 240, and 1440 min after birth. Data were analyzed using PROC MIXED of SAS (SAS Inst. Inc. Cary, NC); the model included fixed effects of litter birth weight quartile and drying treatment and interaction, and time (repeated measure), and random effect of sow. Mean piglet birth weight and rectal temperature at birth were 1.49 ± 0.39 kg and 39.2 ± 0.43°C, respectively. There were no drying by birth weight treatment interactions. Temperatures were similar (P > 0.05) for the drying and birth weight treatments at birth and 240 and 1440 min (Table 1). Drying increased (P < 0.05) rectal temperature from 15 to 180 min; the greatest difference was at 45 min (2.4°C). Temperatures were similar (P > 0.05) for Q2, 3, and 4 from 15 to 180 min. Quartile 1 had a lower (P < 0.05) temperature than the 3 heavier quartiles from 15 to 180 min, except at 120 min when temperatures were similar for Q1 and 2. The lightest piglets exhibited the greatest post-natal temperature decline and drying of piglets at birth reduced the post-natal temperature decline in piglets of all weights. [ABSTRACT FROM AUTHOR]