Using Bio-logging to Improve Sheep Health and Performance

Abstract

The behaviour of sheep has large applications to the UK sheep industry to improve productivity to boost profits and meet global demand. This can be achieved by ensuring maximum reproductive output each year by maximising pregnancy rates, increasing lamb crop sizes and ensuring efficient lamb growth. The advancement in bio-logging technology has facilitated significant advancements in the measurement of animal behaviour and has made the continuous monitoring of the behaviour of farm animals in a commercial setting feasible. A growing body of work has begun to validate this technology in extensive grazing systems and there have been an increasing number of studies linking behaviour measurement to a range of production outcomes. However, evidence is scarce in 3 key areas, including (1) aging, (2) the detection of oestrous and (3) lamb growth and maternal ability which this thesis aimed to explore. Firstly, this thesis aimed to validate the use of bio-loggers in an extensive grazing system, using accelerometers and proximity sensors attached to sheep for 14-day periods at various points in the farm production cycle to collect behavioural data on a commercial sheep flock. Behavioural data was then combined with production records on a pedigree, performance-recorded sheep population and environmental data collected on-farm, to determine links with production traits to investigate how the sheep industry can improve production through maximising reproductive success. This thesis was able to bridge the gap between research and the UK sheep industry, by demonstrating the feasibility of continuously monitoring the behaviour of an entire commercial sheep flock at multiple stages of the production cycle using bio-loggers. Links between behavioural data and production revealed, (i) the presence of age effects on behaviour but no effects on long-term production, (ii) the feasibility of using bio-loggers for the automatic detection of oestrous either indirectly, from ewe-ram social behaviour or directly from ewe behaviour and (iii) lamb and maternal behavioural predictors of lamb growth. As a secondary aim, environmental effects on behaviour were also described, which may prove useful for quantifying the resilience of animals. Advancing our understanding of the measurement of behaviour in a commercial setting and uncovering links with production traits is key to facilitating commercial uptake by the UK sheep industry for real-time monitoring of behaviour and health of sheep flocks to improve performance.