Social behaviour and time budget of breeding bulls
The aim of this study was to investigate the social behaviour and time budget of breedingbulls kept at VikingGenetics, Falkenberg in Sweden when the staff was off duty. It was ofinterest to see if there was any difference between bulls housed in group pens and bullshoused in individual pens. It was also of interest to investigate if there was any differencein the behaviour between the dairy breeds Swedish Red (SR) and Swedish Holstein (SH).Sixteen bulls were used in this study. Eight bulls kept in individual pens and eight bullskept in group pens were used. The individually housed bulls had a social gate with widerbars where the bulls could but their head and neck through to have social contact with thebulls in its neighbouring pens. In each group there were four SH and four SR. Cameraswere mounted to record the behaviour of the bulls. The film material was saved onto harddiscs and decoded manually.The behaviour and time budget of the bulls was analysed from the video between 16:00and 22:00. The bulls? behaviour was analysed during seven days, except for two bulls thatwere only recorded for three days. Instantaneous sampling was used to investigate the timebudget with five minute intervals and continuous sampling was used to investigate socialbehaviour. Mann-Whitney test was used for all the statistical analysis.The group housed bulls showed significantly (p < 0,05) more pushing (median: 0.49 obs./hcompared to 0.05 obs./h) and mounting (median: 0.05 obs./h compared to 0 obs./h) whilstthe individually housed bulls showed significantly more of the behaviours licking muzzle(median: 0.02 obs./h compared to 0 obs./h) and head through gate (median: 0.70 obs./hcompared to 0.11 obs./h). No significant difference was found in the behaviours lickinganother?s body, licking another?s urine/penis, sniffing, butting, rubbing, chin pressing, headto head pushing and being groomed/licked.There were no significant differences in any of the social behaviours between the breeds.The SR however showed a slighter higher frequency of the behaviours licking another?sbody (median: 0.25 obs./h for SR, 0.19 obs./h for SR) and licking urine/penis (median:0.15 obs./h for SR, 0.07 obs./h for SH). SR also had a higher frequency of beinggroomed/licked (median: 0.36 obs./h for SR, 0.31 obs./h for SH).There were no significant differences observed in the time budget between the individuallyhoused bulls and the group housed bulls. The largest difference was seen in locomotion (p= 0.19), where the group housed bulls moved more often than the individually housedbulls. The three most common behaviours were lying ruminating followed by explorationand being social. The median percentages of these behaviours were 52.2%, 18.2% and6.8% respectively for individually housed bulls and 54.3%, 19.7%, 7.4% for group housedbulls.It is concluded that there was no greater difference in social behaviour and time budgetbetween individually housed bulls and group housed bulls as well as between the twobreeds Swedish Holstein and Swedish Red. Due to this both housing systems seem to havesimilar influences on these breeds of bulls.