Effects of different housing systems on haematological profile, salivary cortisol concentration, and behavioural stress responses in calves of different ages

Introduction - European animal welfare legislation (2008/119/EC) poses limitations on the current management practices of Valle d’Aosta breeders. Aim - The haematological profiles, salivary cortisol concentrations, and behavioural responses of Valdostana calves housed in either tie-stalls (TS) or multiple pens (MP) were evaluated in relation to the age at enclosure: very young calves (VYC 7-39 days) or young calves (YC 40-80 days). Materials and methods - Twenty-nine calves were divided into two age groups: VYC (12 females and two males) and YC (13 females and two males). Blood and saliva samples were collected at baseline, at 20 (T1) and at 40 days (T2) after enclosure in one of the two housing systems. Behaviour was analyzed by direct closed-circuit TV recording. Results - Salivary cortisol levels measured at 40 days were significantly higher in the VYC housed in TS than those housed in MP (P<0.01). Differences in haematological profiles were observed only in the animals that had entered indoor housing (TS or MP) at age > 40 days. The VYC housed in TS spent more time in vigilant resting, tended to spend less time sleeping, and exhibited significantly more ruminant activity. Discussion - The type of enclosure for housing calves can affect haematological profiles, cortisol concentrations, and behaviours. A multidisciplinary approach is more effective for evaluating animal welfare than assessment investigating a single parameter. Conclusion - In this study, the hypothesis that MP housing could create stressful conditions in a breed selected for fighting behaviour was not confirmed by our data. The socioeconomic implications of different housing systems need to be studied in geographical areas with natural constraints, such as mountainous regions where local breeds are frequently reared. Animal welfare data on minor local breeds can be useful for informing practices and policies for maintaining biodiversity and breeding of local breed