Zebu group behavior during the pre-slaughter pens waiting
The behavior of cattle previous to slaughter it is still little known limiting our ability to prevent damage and stress by handling. The aim was to characterize the behavior of bulls in the pre-slaughter pens. A total of 11 groups, between 24 and 27 months of age, Brahman breed were included in the study with an average weight (AW) of 447.4 ? 35.4 kg. While in the abattoir, they had access to water, whereas during their transport they were offered no food or water. This study was conducted at an abattoir in Medell?n. The method for measuring the behavior was focal, measuring every 10 minutes the states resting, ruminating and other behaviors (exploring, walking, being alert); and continuous recording for agonistic behaviors (aggression and aggressive response) and water intake (WI), all of them during the first 6 hours after arrival to the abattoir. The activity of all individuals of each group was recorded and the total number of individuals in each activity was reported as frequencies. For statistical analysis, a multiple correspondence and an index of aggressiveness were used: where AI: aggressiveness index; ta: total number of aggressions into the group + i; i: Total individuals within the group; pj: Proportion of events of aggression of the j-th individual in relation to ta. Finally, this aggressiveness index was related to liveweight, environmental temperature (23.79 ? 0.74?C) and humidity (59.09 ? 6.58%), WI (3.07 ? 0.77 times), time of arrival to the pen (between 7:50 and 11:10 am) and average pH 24 hours after slaughter (6.25 ? 0.36). The group behaviors: resting, ruminating and expression of other activities corresponded to 61%, 20% and 19% of the time spent in waiting pens, respectively. AI ranged from 1.33 (19 attacks, 5 aggressors) and 16.22 (125 attacks with 14 aggressors). Only the increase in ambient temperature was associated with AI (p <0.058), and AW was related with changes in pH (p=0.0359). We concluded that the pre-slaughter group activity of animals is associated with the ambient temperature and the individual temperament of the animals in each group. It is recommended that this line of research be continued to identify what other factors may affect behavior in pre-slaughter pens and how this is related to meat quality.