Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 9 (5), e98429

Separation From the Dam Causes Negative Judgement Bias in Dairy Calves


Separation From the Dam Causes Negative Judgement Bias in Dairy Calves

Rolnei R Daros et al. PLoS One.


Negative emotional states in humans are associated with a negative (pessimistic) response bias towards ambiguous cues in judgement tasks. Every mammalian young is eventually weaned; this period of increasing nutritional and social independence from the dam is associated with a pronounced behavioural response, especially when weaning is abrupt as commonly occurs in farm animals. The aim of the current study was to test the effect of separation from the cow on the responses of dairy calves in a judgement task. Thirteen Holstein calves were reared with their dams and trained to discriminate between red and white colours displayed on a computer monitor. These colours predicted reward or punishment outcomes using a go/no-go task. A reward was provided when calves approached the white screen and calves were punished with a timeout when they approached the red screen. Calves were then tested with non-reinforced ambiguous probes (screen colours intermediate to the two training colours). "GO" responses to these probes averaged (± SE) 72±3.6% before separation but declined to 62±3.6% after separation from the dam. This bias was similar to that shown by calves experiencing pain in the hours after hot-iron dehorning. These results provide the first evidence of a pessimistic judgement bias in animals following maternal separation and are indicative of low mood.

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.


Figure 1
Figure 1. Mean±SE % GO responses to screens presented during test sessions before and after a) dehorning (n = 12 calves) and b) separation from the dam (n = 8 calves).
Responses are shown separately for the two training screens (positive and negative) and for the three ambiguous probe screens (near-positive, intermediate and near-negative).
Figure 2
Figure 2. Mean±SE % GO responses to the three ambiguous probe screens (near-positive, intermediate and near-negative) in multiple sessions before dehorning and before separation from dam and multiple sessions after dehorning and after separation from dam.
Different letter indicate a statistically significant difference (p>0.05).

Similar articles

See all similar articles

Cited by 15 articles

See all "Cited by" articles


    1. Enríquez D, Hötzel MJ, Ungerfeld R (2011) Minimising the stress of weaning of beef calves: a review. Acta Vet Scand 53: 28. - PMC - PubMed
    1. Hudson S, Mullord M (1977) Investigations of maternal bonding in dairy cattle. Appl Anim Ethol 3: 271–276.
    1. Martin P (1984) The meaning of weaning. Anim Behav 32: 1257–1258.
    1. Von Keyserlingk MAG, Weary DM (2007) Maternal behavior in cattle. Horm Behav 52: 106–113. - PubMed
    1. Flower F, Weary D (2003) The effects of early separation on the dairy cow and calf. Anim Welf: 339–348.

Publication types

Grant support

This work was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC). RRD was supported by scholarships from CAPES (Coordenação de aperfeiçoamento de pessoal de nível superior) and ELAP (Emerging Leaders in the Americas Program). JHCC was supported by a scholarship from CNPq (Conselho Nacional de Desenvolvimento Cientifçco e Tecnológico). MJH thanks CNPq for their general support through grant number 304123/2012-9. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript