Can individual variation in food neophobia explain variability in dairy calf feeding behavior patterns and performance?

Abstract

Food neophobia is the avoidance of novel feeds, arising from an attempt to avoid potentially toxic and unwanted feeds, and is very common in ruminants. In commercial dairy settings, hesitancy to consume novel feeds is detrimental to animal performance and may be associated with other traits that can negatively affect animals in intensive and modern production systems. The aim of this study was to investigate the relationship between food neophobia and the development of solid and milk feeding behaviors, and consequently with calf performance up to two weeks post-weaning. We subjected dairy calves at 83 ± 3 d of age to a food neophobia test with a novel feed (corn silage-based total mixed ration), a familiar feed (alfalfa hay), and an empty container. Behaviors measured from this food neophobia test were condensed into three factors using a principal component analysis: ‘Feed Avoidant’, ‘Active’, and ‘Attentive’. A regression analysis was performed to assess if scores for the three factors were associated with feeding behavior patterns measured via an automatic feeder system, including total milk intake, rewarded and unrewarded visits to the milk feeder, total calf starter intake, and age at which calves first consumed ≥ 1 kg of calf starter. Factor 1 (‘Feed Avoidant’) was positively associated with the number of rewarded visits to the automated milk feeder but was not associated with intake of calf starter or milk replacer, nor performance of dairy calves. The other factors identified from the food neophobia test showed associations with feeding behavior patterns and performance. Factor 2 (‘Active’) was positively associated with calf starter intake during the weaning, post-weaning, and total periods, and was associated with a younger age at which calves consumed 1 kg of calf starter. Factor 3 (‘Attentive’) was positively associated with number of rewarded visits to the feeder during preweaning, increased calf starter intake during weaning and total periods, and higher preweaning ADG. These results suggest that individual variation in the willingness to interact with novel and familiar feeds may not play a large role in the development of solid feeding behaviors or performance of group housed dairy calves, but other traits identified from the food neophobia test are associated with performance and feeding behavior that can be measured in standardized tests.