Planimetric Determination of the Static Space of Cull Sows as the First Step towards a Recommendation of Loading Densities for Cull Sows during Road Transportation in the European Union

Abstract

The available floor space is an important welfare factor for cull sows during transportation. Sows of modern genetics reach a size and weight far exceeding those of fattening pigs. In most countries, there are no binding, consistent regulations for the maximum loading densities, especially for sows during road transportation. As a first step towards such recommendations, the physical floor space requirement (static space) of 100 sows of a current breed, while standing and lying down, were determined using contrast-based planimetry. An average sow covered about 0.42–0.47 m2 (standing postures) up to 0.53–0.63 m2 (lying postures). The largest measured area was 0.72 m2 for a sow lying in the belly-chest position. We detected a significant dependency of the covered floor area and the live weight, which supports the common practice to derive space requirements and recommendations based on live weight. Also, our results suggest that especially heavy sows, under currently usual loading densities, are at risk of having insufficient floor space requirements during transport. The results cannot be used to define the space required by a sow to carry out movements or sustain the individual need for distance (social/dynamic space) but provide data on the static space covered by sows of current breeds.

Welfare of pigs on farm

“…Curtis et al (1989) estimated that in order to get up and lie down comfortably, a sow weighing 300 kg uses 220 cm in length and 86 cm in width. Thus, a stall measuring less than 220 × 86 cm will impede natural lying down and getting up behaviour (Arndt et al, 2020).…”

Welfare of pigs during transport

“…However, comparing sow dimensions for length, width and height between that calculated by the allometric equations proposed by Petherick and Philips (2009) to the measurements taken by Moustsen et al (2011), in Danish sows ranging from parity 1 to 7, indicates that the allometric equations continue to provide close estimations of the body dimensions of these modern genetics. Planimetric analysis of the static space floor area occupied by sows in different postures (average sow weight 235 kg, min: 187; max: 310 kg) has identified that when standing, the occupied floor area ranges from 0.42 m 2 to 0.47 m 2 (min: 0.34; max: 0.59 m 2 ), and sternal lying requires an average floor space of 0.63 m 2 (min: 0.52; max: 0.71 m 2 ), (Arndt et al, 2020). This is lower than the minimum space allowance estimated for sows to stand and lie sternally as calculated with a k-value of 0.019.…”

“…Planimetric analysis of the static space floor area occupied by sows in different postures (average sow weight 235 kg, min: 187; max: 310 kg) has identified that when standing, the occupied floor area ranges from 0.42 m 2 to 0.47 m 2 (min: 0.34; max: 0.59 m 2 ), and sternal lying requires an average floor space of 0.63 m 2 (min: 0.52; max: 0.71 m 2 ), (Arndt et al., 2020). This is lower than the minimum space allowance estimated for sows to stand and lie sternally as calculated with a k‐value of 0.019.…”

“…Multiple factors affect the use of space by pigs during transport, including the age and category of pig (weaner, finisher, sows/boars), microclimatic conditions and journey duration. Body weight and dimensions change with the pig category and age (Condotta et al, 2018), and are related to the space required (Arndt et al, 2019(Arndt et al, , 2020. It is, thus, a complex issue to provide a minimum recommended space allowance during transport that will be applicable within all situations.…”