The effect of farrowing crate heat lamp location on sow and pig patterns of lying and pig survival.

Three experiments were conducted to study sow and pig behavior during the 1st 3 d after birth and pig survival during the 1st 2 wk after farrowing. In Exp. 1, 23 sows were housed in conventional farrowing crates that were divided into five sections: a .5- x 1.5-m front creep section and the remaining area divided into four sections, .75 x 1.05 m each. Air temperature was maintained at 19 degrees C, and a 250-W heat lamp was placed at the right side of the front creep in Treatment 1 (T1), or in the creep at the right side of the sow for Treatment 2 (T2). The percentage of pigs within 8 cm of the sow's trunk was not affected by treatment, but it decreased (P < .001) from 61.8 +/- 3.4% on d 1 to 28.1 +/- 3.5% on d 3. As the percentage of pigs near the sow decreased, the percentage of pigs within the section containing the heat lamp increased (T1, P < .05; T2, P < .10). Experiment 2 involved 15 sows and litters housed as in Exp. 1, except that heat lamps were not provided, and average air temperature was 27.3 +/- .2 degrees C during behavioral observations. Even though the portion of the litter near the sow decreased (P < .001) from d 1 to d 3 (d 1, 57.0 +/- 3.4%; d 2, 42.9 +/- 3.3%; d 3, 31.7 +/- 3.3%), pigs did not concentrate in any specific section as they moved away from the sow. The average number of pigs within the front creep section (Section 1) for the 3-d period was less than (P < .01) the number in any other crate section. Experiment 3 involved 147 sows and tested the effect of solid creep floor covering on pig survival for each of the heat lamp locations used in Exp. 1. Neither heat lamp location nor floor covering affected pig survival. During the 1st 3 d of life, pigs tend to lie near the sow regardless of heat lamp location or air temperature. Heat lamp position and floor covering under the lamp do not affect pig survival.