Single- and multi-species groups: a descriptive study of cattle and broiler behaviour on pasture.

Abstract Farming with more than one livestock species has been discussed as a more sustainable agricultural production system than specialisation. Some potentially positive effects of multi-species livestock farming can only be utilised when different species share space, e.g. by co-grazing. To date there is limited research on the behaviour of animals in multi-species livestock groups. If this practice is adopted more widely, it will be important to investigate the effect of co-grazing on the animals' behaviour and subsequently their welfare. One of the most prevalent species combinations in a survey of 126 multi-species livestock farms was cattle and poultry. Therefore, we aimed to describe and quantify inter-species interactions between young cattle and broiler chickens when co-grazing and descriptively compare intra-species interactions and a wide range of behaviours between single- and multi-species groups of young cattle and broiler chickens on pasture. Additionally, we assessed fearfulness in broiler chickens as measured by Tonic Immobility (TI), Inversion test and Novel Object test. Across five six-week cycles we observed three groups each: One single-species group of ten cattle, one single-species group of 54 to 61 broilers, and one multi-species group of ten cattle and 54 to 61 broilers. Once per week the multi-species group was observed for in total 120 min using behaviour sampling to quantify the occurrence of inter- and intra-species interactions. On two other days per week, single- and multi-species groups were observed in a balanced order using continuous focal animal sampling to assess frequency and duration of pre-defined behaviours for ten animals per species for 6 min each. During all observations scan sampling was performed every 6 minutes to count the number of visible animals per pasture sector. Across observation methods, two independent observers achieved high agreement for most behaviours. Inter-species interactions occurred two to three times per hour and ten animals per species, and intra-species interactions occurred between 18 and 28 times per hour and ten cattle or broilers. The most frequently observed inter-species interactions were cattle displacing broiler and broiler approaching cattle. A wide range of behaviours did not differ between animals in single- and multi-species groups, including measures of fearfulness, but the variation was high across observations. These findings should be verified with a greater number of animals and groups to be more applicable to commercial settings, but we can tentatively conclude that co-grazing did not affect cattle or broilers negatively.