Alistair B Lawrence

• IGF-1 gene expression upregulated in frontal cortex of piglets after EE protocol. • Trend towards similar increase in BDNF post enrichment. • Evidence of potential CNS benefits of EE. • No difference in exploration or walking behaviour in enriched arena vs home pen. • Species typical behaviours (rooting/foraging) increased in enriched arena while inactivity decreased. a b s t r a c t Environmental enrichment (EE) is widely used in the life sciences to study effects of environment on the brain. In pigs, despite lack of EE being a key welfare issue there is little understanding of brain effects of EE in pigs. This project aimed to study the effects of exposure to an EE arena on piglet behaviours and on brain gene expression levels with a focus on IGF-1 and related genes. Eight litters of large white × landrace × Hampshire piglets were farrowed and raised in a free farrowing system (PigSAFE). At 42 days of age, 6 piglets per litter were given access to an enriched arena with plentiful peat, straw and space, (in groups of 4 made up of stable pairs) for 15 min per day on 5 consecutive days to allow them to habituate to the apparatus. Piglet behaviours were recorded in the arena for 15 min periods on 3 consecutive days. On the final day only one pair of test piglets per litter was given access to the arena. Brain tissue was collected within 45 min of the test from piglets exposed to the arena on the day and their non-exposed littermate controls. RNA was extracted from the frontal cortex and QRT-PCR for selected genes run on a Stratgene MX3005P. In both the home pen and the EE arena litters spent the largest proportion of time engaging in foraging behaviour which was significantly increased in the enriched arena (t 7 = 5.35, df = 6, p = 0.001). There were decreases in non-running play (t 7 = 4.82, p = 0.002) and inactivity (t 7 = 4.6, p = 0.002) in the arena. A significant fold change increase (FC = 1.07, t = 4.42, p = 0.002) was observed in IGF-1 gene expression in the frontal cortex of piglets exposed to the enriched arena compared to those not exposed on the day of culling. No change in expression was observed in CSF1, the IGF-1 receptor gene nor in any of the binding proteins tested (IGFBP1-6). There was a weak tendency for increased expression of the neurotrophic factor BDNF1 (fold change: 1.03; t 7 = 1.54, p = 0.1). We believe this work is the first to explore effects of EE on pig brain physiology and development, and also points to a potential role for IGF-1 in brain effects of EE.

Flight speed (FS) is an objective measure of the behavioural response to handling procedures in beef cattle but to date there is no published work on dairy cattle. It is useful to determine whether there is consistency in FS in dairy cattle, and assess the relationship between FS and other subjective measures of responsiveness in dairy cattle. The aims of

Summary In intensive farming situations, growing animals are housed in relatively barren environ-ments. The lack of opportunity to perform substrate-interactive and manipulative behaviour patterns may affect the expression and organization of these behaviours. However, mak- ...

The relationship between the performance of post-feeding stereotypic behaviour and plasma cortisol levels and the effect of prevention of stereotypic behaviour on plasma cortisol levels were studied in chronically restrained sows. In experiment 1 sows classified as high or low stereotypers on the basis of time spent manipulating chain and behaviour directed to the nipple drinker were found not to differ in plasma cortisol levels. Removing the chain and nipple drinkers also did not affect cortisol concentrations of either group. In experiment 2 detailed recordings were made by an automatic logging system of two major categories of stereotypy; chain manipulation and drinking. There were large individual differences in levels of both chain manipulation and drinking. Both activities showed a similar diurnal pattern, but average levels across individuals were not correlated. Both activities showed a continuous distribution across individuals and therefore a correlational rather than factorial analysis was used. Chain manipulation was not correlated to cortisol concentrations on any of the control days and removing the chain for one day (experiment 2A) or for seven days (experiment 2B) was also not accompanied by increased cortisol levels. However individuals showed a consistent cortisol response to chain removal as indicated by correlations between treatment days. Drinking showed a tendency to be negatively correlated to cortisol concentrations on control days. Long-term chain removal was accompanied by an increase in average drinking that showed a non-significant tendency to be negatively correlated to plasma cortisol on treatment days and thus may explain part of the consistency of response to chain removal. The lack of correlation between chain manipulation and plasma cortisol suggests that this activity does not serve to reduce plasma cortisol in chronically restrained sows. The relationship between drinking and cortisol need not necessarily reflect the coping capacity of this behaviour but may be a physiological consequence of the large amounts of water ingested.