Planimetric measurement as a method for scientific assessment of space requirements of young suckling piglets in the creep area

Abstract

In recent years, litter sizes of pigs have continuously increased. In modern pig production, litters with up to 15 or even more piglets born alive are no longer an exception. However, the size of heated creep areas, in which the piglets can retire to rest, has not yet been adapted to the increasing number of piglets per litter. Therefore, the objective of this study was to determine the space requirements of piglets lying in a creep area in order to assess whether common sizes of creep areas are still sufficient to accommodate all piglets of a litter. Thus, the exact floor space that suckling piglets of different weight classes occupied due to their physical size and shape was measured automatically using the colour contrast planimetric method “KobaPlan”. A total number of 234 images of piglets from 0.5kg to 6kg was taken from top view in a special planimetric box. In the digital photo, the number of animal associated pixels was counted by the “KobaPlan” software and compared to a reference area. Thus, the area covered by the individual piglet was calculated. Thereby, it was possible to determine the space the piglets dissipated in lateral and ventral recumbent positions up to the age of three weeks. The results revealed that the space requirements of piglets increased linearly with their weights, independent of lying position. The mean floor space covered by piglets weighing 0.5–1.5kg lying on their bellies was 249±42cm2, and piglets lying in lateral position covered 275±33cm2. Piglets weighing 3.0–4.5kg covered more space than lower weight classes in ventral (554±68cm2) and lateral positions (502±41cm2). Piglets in the heaviest weight class (4.5–6.0kg) required 633±52cm2 when lying in a lateral position. Assuming that all piglets were lying in lateral recumbency, for a litter size of 12 piglets weighing up to 6.0kg, a space requirement of 0.76m2 was calculated. For 14 piglets, an area of 0.9m2, and for 16 piglets 1.01m2 is needed. Bearing in mind that litter sizes are growing, a creep area of approximately 0.9m2 is recommended for piglets up to three weeks of age based on a space requirement of 0.06m2 per piglet.