Michel Thériez

Effects of stocking density on the behaviour and growth of farmed red deer hinds

Abstract The aim of this experiment was to measure the effects of stocking density on the social behaviour, activity patterns and growth rates of yearling red deer hinds reared at pasture. Twenty individuals were assigned to two groups of 10 in a latin square design. During period 1 (28 days), group 1 was kept at a low stocking density (LD: 37 animals/ha) and group 2 at a high stocking density (HD: 150 animals/ha). During period 2 (28 days) the groups were switched and tested at the other stocking density. Aggressive encounters (kicks, bites and butts) and vigilance postures were more frequent at HD than at LD. There was no difference between the two densities in the total time spent grazing per day, but the hinds at HD had shorter and more frequent meals than the hinds at LD. The synchronisation of grazing was also lower at HD than at LD. The hinds grew faster at LD than at HD. The effects of stocking density on growth and grazing behaviour were more severe for subordinate than for dominant hinds. In conclusion, high stocking density induced a social stress that affected grazing patterns and growth rates, especially in subordinate individuals.

Effects of mixed-species stocking and space allowance on the behaviour and growth of red deer hinds and ewes at pasture

Abstract Our objective was to test whether the effects of space allowance on social interactions, activity patterns and growth rates of hinds reared at pasture in single-species groups, were modified by mixing them with ewes. Thirty individuals of each species were assigned to two single-species groups of 10 animals (hinds: H1 and H2, ewes: E1 and E2) and to two mixed-species groups of 5 hinds and 5 ewes (M1 and M2). For 28 days, H1, E1 and M1 were kept at high space allowance (HSA: 267 m 2 /animal) and H2, E2 and M2 at low space allowance (LSA: 67 m 2 /animal) and for the following 28 days, the space allowance was reversed. Mean interindividual distances in single-species groups were lower at LSA than at HSA (hinds: 10.0±0.3 vs. 15.4±4.8 m, P P P P P

In vivo estimation of body composition from the dilution space of deuterium oxide in fat-tailed Barbary ewes

Abstract Sixteen dry ewes of the fat-tailed Barbary breed were used to formulate prediction equations of body water, fat, protein and energy content from the live body weight (BW) and the dilution space of deuterium oxide (SD 2 O). Ewes were injected with 0.5 g D 2 O/kg BW and four blood samples collected after infusion. The D 2 O content of blood water was determined by infra-red spectrometry. Ewes were weighed, body condition scored and then slaughtered. The body water, fat, protein, ash and energy were chemically determined. At slaughter, ewes weighed 43.4±7.0 kg, and contained 26.0±2.6 kg of water and 9.3±4.2 kg of fat. A relative lack of variation in the fat-free empty body (FFEB) was confirmed in this particular breed (water percentage, 74.5±1.6). Adiposity (fat as percent empty BW; EBW) varied between 15.1 and 36.9%. There was a close negative relationship ( R 2 =0.96; residual standard deviation (R.S.D.)=1.4%) between the fat and the water content of EBW. Body water was significantly correlated with SD 2 O. The body fat and energy content prediction equations from SD 2 O and BW were similar to those published in a thin-tailed ewe breed ( R 2 =0.92; R.S.D.=1.4 kg). The body fat equation prediction from body condition score and/or BW was significant ( R 2 =0.81; R.S.D.=1.9 kg) although not as precise as that using D 2 O.