vaccination and subsequent experimental infection outcomes are associated with changes in vitamin D status in dairy calves.

Investigations into the role of vitamin D (vitD) in the immune response of cattle are limited. The objectives of this study were therefore to investigate the association between circulating vitD concentration, tuberculosis (TB) vaccination, and infection outcomes in 24 dairy calves (<8 wk old) that were housed throughout and fed a BW-based allowance. The study design incorporated 2 phases: vaccination (experimental wk 0-52) and experimental infection phase (wk 52-65).

A meta-analysis of the sources of variation in the environmental impacts of different broiler production systems.

1. Shifting to higher welfare systems is expected to increase their environmental impact and mitigation strategies need to be identified. The environmental impacts associated with various broiler production systems (BPS: conventional, higher welfare indoors, free-range or organic) and the characteristics of BPS which contribute to these impacts were investigated via a literature review and meta-analysis.

Unravelling the mechanisms underlying the social interaction effects on the feed efficiency of rabbits.

The feed consumption and feeding patterns of group-housed livestock and their productive outputs can be affected by interactions among group members, such as competition for feeder access and aggression. The impact of competition is especially significant when feed restriction is implemented during the fattening stage, a common practice in rabbit farms to reduce mortality from digestive disorders during this period. The overall aim was to quantify the importance of social interaction effects at the genetic and environmental level on feed efficiency, feeding behaviour and social ranking traits in rabbit populations having access to electronic feeders whilst they were housed in groups during fattening.

Towards the identification of transmission pathways and early detection of Enterococcus cecorum infection in broiler chickens.

Enterococcus cecorum (EC) infection is an emerging endemic disease in UK and global broiler poultry with major economic impact and welfare concerns. There are significant research gaps with regards to EC pathogenesis, source of infection, transmission routes and early detection of disease, which this study aimed to address. In this prospective study, 725 environmental samples were collected from 4 broiler farms (A-D) the day before chick placement (d 1) and through the subsequent crop (d 7, 14, and 21).

Improve animal health to reduce livestock emissions: quantifying an open goal.

Greenhouse gas (GHG) emissions from livestock production must be urgently tackled to substantially reduce their contribution to global warming. Simply reducing livestock numbers to this end risks impacting negatively on food security, rural livelihoods and climate change adaptation. We argue that significant mitigation of livestock emissions can be delivered immediately by improving animal health and hence production efficiency, but this route is not prioritized because its benefits, although intuitive, are poorly quantified.