PRECISION LIVESTOCK FARMING AND PERSONALITY AS TOOLS TO UNDERSTAND DAIRY CALF INDIVIDUAL VARIATION IN PERFORMANCE, BEHAVIOR, AND RESPONSE TO STRESS

Individual differences impact animal responses to their environments and can be observed with animal personality (stable behavioral differences with populations) and food neophobia (avoidance of unfamiliar feeds). These individual differences can influence cattle performance and welfare. Precision technologies, such as automatic feeding systems (AFS) and accelerometers continuously measure feeding behaviors and activity and may allow us to relate individual differences to behaviors in the home environment. Therefore, the first objective was to determine if food neophobia was associated with feeding behaviors measured by AFS. Food neophobia was associated with rewarded visits to the AFS, but to no other feeding behaviors. The second objective was to determine if personality traits (PT) were associated with activity, feeding behavior, and average daily gain (ADG). The PT ‘active’ was associated with higher activity in the home environment, more starter consumed, and with greater ADG overall. The PT ‘explorative’ was associated with less starter consumed and lower ADG only during weaning. Finally, the last objective was to determine if PT were associated with the magnitude change in feeding behaviors and activity during stressful events, including weaning, dehorning, and disease. We found that the PT ‘fearful’, ‘active’, and ‘explorative’ were linked to the magnitude of behavioral changes during stressors, though these associations varied with stressor type. These studies provide evidence that individual differences in dairy calves relate to precision technology behaviors, solid feed intake, performance, and response to stressors. These studies highlight the importance of considering the individual for optimal welfare and performance of dairy cattle

ISOLATION BOX TEST (IBT) AND DAIRY CALF PERSONALITY TRAITS RELATIONSHIP WITH PERFORMANCE THROUGH WEANING

Personality tests are utilized to characterize individual differences in personality traits across species. Currently, there is no objective personality test that can be implemented on-farm to measure personality in dairy calves. Measuring personality of youngstock in the dairy industry may allow producers to utilize information on individual differences for management decisions and limit the investment in unfit individuals. The isolation box test is a personality test that has potential to be adapted and utilized for dairy calves. The main objective of this thesis is to develop, validate, and utilize an isolation box test for use on-farm in dairy calves. More specifically, the objectives of this thesis are to determine if an isolation box test can determine individual differences in dairy calves, if outcomes from the isolation box test agree with outcomes of established standardized personality tests, and if outcomes from an isolation box test can predict performance outcomes through weaning in dairy calves. The measures produced from an isolation box test were associated with outcomes of standardized personality tests (novel person, novel object, and startle tests) and growth through weaning. The isolation box test has potential to be used as a personality test in dairy calves on-farm

Development and Utilization of an Isolation Box Test to Characterize Personality Traits of Dairy Calves

The use of an isolation box test (IBT) to characterize personality traits has been used in non-bovine species with success. We aimed to develop an IBT for dairy calves and determine if the behavioral responses to an IBT were associated with personality traits found from traditional tests (novel person, novel object, and a startle tests) and average daily gain (ADG; Kg/d) through weaning. Calf movement while in the IBT was measured via accelerometers attached to 5 locations on the exterior of the box. A total movement index (TMI) was calculated based on accelerometer readings during the IBT. We performed a principal component analysis on the traditional tests and identified 3 influential factors that we labeled as “fearful,” “bold,” and “active.” Calves were weighed biweekly to track liveweight ADG. Factor scores and ADG were regressed against TMI. A significant negative association was found between the TMI and the factor “active,” indicating the validity of IBT as a tool for assessing some personality traits of dairy calves. Furthermore, TMI had a positive association with ADG through the entire experimental period and thus has potential to help predict performance through weaning. IBT has potential to be used as a personality test in research scenarios. Further development is needed to produce an IBT that would be appropriate to measure animals\u27 responses reliably in production settings. An automated test that can accommodate a wide range of ages and developing a computer learning model to interpret output from the IBT would be a possible option to do so