Space Availability in Confined Sheep during Pregnancy, Effects in Movement Patterns and Use of Space

Abstract

Space availability is essential to grant the welfare of animals. To determine the effect of space availability on movement and space use in pregnant ewes (Ovis aries), 54 individuals were studied during the last 11 weeks of gestation. Three treatments were tested (1, 2, and 3 m2/ewe; 6 ewes/group). Ewes' positions were collected for 15 minutes using continuous scan samplings two days/week. Total and net distance, net/total distance ratio, maximum and minimum step length, movement activity, angular dispersion, nearest, furthest and mean neighbour distance, peripheral location ratio, and corrected peripheral location ratio were calculated. Restriction in space availability resulted in smaller total travelled distance, net to total distance ratio, maximum step length, and angular dispersion but higher movement activity at 1 m2/ewe as compared to 2 and 3 m2/ewe (P<0.01). On the other hand, nearest and furthest neighbour distances increased from 1 to 3 m2/ewe (P<0.001). Largest total distance, maximum and minimum step length, and movement activity, as well as lowest net/total distance ratio and angular dispersion were observed during the first weeks (P<0.05) while inter-individual distances increased through gestation. Results indicate that movement patterns and space use in ewes were clearly restricted by limitations of space availability to 1 m2/ewe. This reflected in shorter, more sinuous trajectories composed of shorter steps, lower inter-individual distances and higher movement activity potentially linked with higher restlessness levels. On the contrary, differences between 2 and 3 m2/ewe, for most variables indicate that increasing space availability from 2 to 3 m2/ewe would appear to have limited benefits, reflected mostly in a further increment in the inter-individual distances among group members. No major variations in spatial requirements were detected through gestation, except for slight increments in inter-individual distances and an initial adaptation period, with ewes being restless and highly motivated to explore their new environment.

Pen size and parity effects on maternal behaviour of Small-Tail Han sheep

“…Chiumenti (1987) suggests that 0.9 to 1.2 m 2 /head on straw litter and 0.8 to 1.0 m 2 /head on slatted floor are fit for sheep. However, studies on sheep behaviour suggest that housing at 1 to 1.5 m 2 (as in the small pens in the present study) results in higher social interactions and reduced activity compared with lower stocking density (Caroprese et al, 2009;Averòs et al, 2014b). Conversely, very low space availability increases activity, as animals are prevented from lying down when they wish (Bøe et al, 2006).…”

“…As a solution to this, sheep production is gradually shifting from extensive to intensive management, with increased housing of ewes during pregnancy and lactation, and housing at increasing stocking density. However, there is still little information available about the impact of sheep housing and stocking density on sheep production and welfare, although recent studies suggest that high stocking density results in behavioural disturbances, displacements and altered social interactions (Averòs et al, 2014a and2014b). It is, therefore, relevant to consider how this might also affect the behaviour of Chinese sheep breeds.…”

“…High stocking densities affect sheep behaviour, physiology and welfare (Sevi et al, 1999;Caroprese et al, 2009;Averòs et al, 2014a and2014b), and it may also affect motheryoung interactions (Averòs et al, 2014a;Dwyer, 2014). Crowded conditions may exacerbate lamb desertion or separation behaviour in paddocks (Winfield, 1970) and are likely to be even greater in indoor housing conditions.…”

The Impact of Group Size on Welfare Indicators of Ewes during Pregnancy

“…Randomization was carried out by permutations of experimental enclosures, permutation of enclosures and ewes within each enclosure (www.random.org), or simple random sampling techniques (www.randomizer.org) depending on specific needs. Within each scan the withers position (in XY coordinates; expressed as X and Y distances from the origin of coordinates, in cm) of all ewes in the enclosure was sequentially collected, with the help of a visual grid, using the Chickitizer software [8,22]. The behaviour of each ewe was simultaneously collected with the software following the ethogram shown in Table 1.…”

“…Dairy ewes are often indoors during part of their gestation, and it is possible that the resulting space restriction and imposed GS have undesired consequences. In this sense, it has been shown that limiting space availability influences ewes’ spatial distribution, movements and behaviour [7,8], even in cases of moderate spatial limitation [9]. Besides space allowance, the effects of GS need also consideration in indoor housed pregnant ewes since it will largely determine their social dynamics [10,11].…”