Limits...
Individual recognition in domestic cattle (Bos taurus): evidence from 2D-images of heads from different breeds.

Coulon M, Deputte BL, Heyman Y, Baudoin C - PLoS ONE (2009)

Bottom Line: Our results demonstrated that cattle have efficient individual recognition based on categorization capacities.Social familiarity improved their performance.These results call for studies exploring the mechanisms involved in face recognition allowing interspecies comparisons, including humans.

View Article: PubMed Central - PubMed

Affiliation: Université Paris 13, CNRS UMR 7153, Laboratoire d'Ethologie Expérimentale et Comparée, Villetaneuse, France. marjorie.coulon@leec.univ-paris13.fr

ABSTRACT

Background: In order to maintain cohesion of groups, social animals need to process social information efficiently. Visual individual recognition, which is distinguished from mere visual discrimination, has been studied in only few mammalian species. In addition, most previous studies used either a small number of subjects or a few various views as test stimuli. Dairy cattle, as a domestic species allow the testing of a good sample size and provide a large variety of test stimuli due to the morphological diversity of breeds. Hence cattle are a suitable model for studying individual visual recognition. This study demonstrates that cattle display visual individual recognition and shows the effect of both familiarity and coat diversity in discrimination.

Methodology/principal findings: We tested whether 8 Prim'Holstein heifers could recognize 2D-images of heads of one cow (face, profiles, (3/4) views) from those of other cows. Experiments were based on a simultaneous discrimination paradigm through instrumental conditioning using food rewards. In Experiment 1, all images represented familiar cows (belonging to the same social group) from the Prim'Holstein breed. In Experiments 2, 3 and 4, images were from unfamiliar (unknown) individuals either from the same breed or other breeds. All heifers displayed individual recognition of familiar and unfamiliar individuals from their own breed. Subjects reached criterion sooner when recognizing a familiar individual than when recognizing an unfamiliar one (Exp 1: 3.1+/-0.7 vs. Exp 2: 5.2+/-1.2 sessions; Z = 1.99, N = 8, P = 0.046). In addition almost all subjects recognized unknown individuals from different breeds, however with greater difficulty.

Conclusions/significance: Our results demonstrated that cattle have efficient individual recognition based on categorization capacities. Social familiarity improved their performance. The recognition of individuals with very different coat characteristics from the subjects was the most difficult task. These results call for studies exploring the mechanisms involved in face recognition allowing interspecies comparisons, including humans.

Show MeSH
Individual recognition of a familiar Prim'Holstein cow.Example of the pairs of stimuli presented in consecutive trials of the generalization test. The stimulus rewarded is framed in red.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2636880&req=5

pone-0004441-g002: Individual recognition of a familiar Prim'Holstein cow.Example of the pairs of stimuli presented in consecutive trials of the generalization test. The stimulus rewarded is framed in red.

Mentions: Eight PH heifers were tested with an instrumental conditioning with food reward. They were individually introduced into a test pen which included a central lane made of rows of straw bundle. A guillotine gate ended the central lane from which position heifers could see a pair of stimuli. When the subject had observed both stimuli, the experimenter lifted the gate. Then the heifer walked to the chosen image and accessed a reward placed behind an opaque panel (the test pen and procedures were described in more details in [24]). A test session included ten consecutive trials. Stimuli were photographs of head of heifers under various angles (frontal, profile, ¾ front views, ¾ back views and mirror views, Figure 1) on the same yellowish background. In the training phase, the same pair of stimuli was used in each trial. This pair was composed of a front view of the heifer to identify ( = sample individual) with a front view of another heifer (Figure 1). The subject had to choose the image of the other heifer to access to the reward. In generalization test, we used new photographs of the sample heifers and of other heifers, and the pair of stimuli was changed on each trial (Figure 2). The subject always had to choose the image of the other heifer to be rewarded. The criterion of success was for the heifer to make at least 8 correct choices per session in two consecutive sessions of 10 trials. The eight heifers were tested in four different experiments each of which made of a training phase and a generalization test. In the first experiment, we used images of familiar Prim'Holstein (FPH) heifers, in the second experiment images of unfamiliar Prim'Holstein (UPH) heifers, in the third experiment images of unfamiliar Normande (N) heifers and in the fourth experiment images of unfamiliar Charolaise (CH) heifers. Experiments 1 (FPH) and 2 (UPH), on the one hand, and experiments 3 (N) and 4 (CH), on the other hand, were paired. In each pair of experiments, half of the subjects were assigned to one experiment to start with (1 or 2 and 3 or 4). This procedure was intended to avoid a “carry-over” effect.


Individual recognition in domestic cattle (Bos taurus): evidence from 2D-images of heads from different breeds.

Coulon M, Deputte BL, Heyman Y, Baudoin C - PLoS ONE (2009)

Individual recognition of a familiar Prim'Holstein cow.Example of the pairs of stimuli presented in consecutive trials of the generalization test. The stimulus rewarded is framed in red.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2636880&req=5

pone-0004441-g002: Individual recognition of a familiar Prim'Holstein cow.Example of the pairs of stimuli presented in consecutive trials of the generalization test. The stimulus rewarded is framed in red.
Mentions: Eight PH heifers were tested with an instrumental conditioning with food reward. They were individually introduced into a test pen which included a central lane made of rows of straw bundle. A guillotine gate ended the central lane from which position heifers could see a pair of stimuli. When the subject had observed both stimuli, the experimenter lifted the gate. Then the heifer walked to the chosen image and accessed a reward placed behind an opaque panel (the test pen and procedures were described in more details in [24]). A test session included ten consecutive trials. Stimuli were photographs of head of heifers under various angles (frontal, profile, ¾ front views, ¾ back views and mirror views, Figure 1) on the same yellowish background. In the training phase, the same pair of stimuli was used in each trial. This pair was composed of a front view of the heifer to identify ( = sample individual) with a front view of another heifer (Figure 1). The subject had to choose the image of the other heifer to access to the reward. In generalization test, we used new photographs of the sample heifers and of other heifers, and the pair of stimuli was changed on each trial (Figure 2). The subject always had to choose the image of the other heifer to be rewarded. The criterion of success was for the heifer to make at least 8 correct choices per session in two consecutive sessions of 10 trials. The eight heifers were tested in four different experiments each of which made of a training phase and a generalization test. In the first experiment, we used images of familiar Prim'Holstein (FPH) heifers, in the second experiment images of unfamiliar Prim'Holstein (UPH) heifers, in the third experiment images of unfamiliar Normande (N) heifers and in the fourth experiment images of unfamiliar Charolaise (CH) heifers. Experiments 1 (FPH) and 2 (UPH), on the one hand, and experiments 3 (N) and 4 (CH), on the other hand, were paired. In each pair of experiments, half of the subjects were assigned to one experiment to start with (1 or 2 and 3 or 4). This procedure was intended to avoid a “carry-over” effect.

Bottom Line: Our results demonstrated that cattle have efficient individual recognition based on categorization capacities.Social familiarity improved their performance.These results call for studies exploring the mechanisms involved in face recognition allowing interspecies comparisons, including humans.

View Article: PubMed Central - PubMed

Affiliation: Université Paris 13, CNRS UMR 7153, Laboratoire d'Ethologie Expérimentale et Comparée, Villetaneuse, France. marjorie.coulon@leec.univ-paris13.fr

ABSTRACT

Background: In order to maintain cohesion of groups, social animals need to process social information efficiently. Visual individual recognition, which is distinguished from mere visual discrimination, has been studied in only few mammalian species. In addition, most previous studies used either a small number of subjects or a few various views as test stimuli. Dairy cattle, as a domestic species allow the testing of a good sample size and provide a large variety of test stimuli due to the morphological diversity of breeds. Hence cattle are a suitable model for studying individual visual recognition. This study demonstrates that cattle display visual individual recognition and shows the effect of both familiarity and coat diversity in discrimination.

Methodology/principal findings: We tested whether 8 Prim'Holstein heifers could recognize 2D-images of heads of one cow (face, profiles, (3/4) views) from those of other cows. Experiments were based on a simultaneous discrimination paradigm through instrumental conditioning using food rewards. In Experiment 1, all images represented familiar cows (belonging to the same social group) from the Prim'Holstein breed. In Experiments 2, 3 and 4, images were from unfamiliar (unknown) individuals either from the same breed or other breeds. All heifers displayed individual recognition of familiar and unfamiliar individuals from their own breed. Subjects reached criterion sooner when recognizing a familiar individual than when recognizing an unfamiliar one (Exp 1: 3.1+/-0.7 vs. Exp 2: 5.2+/-1.2 sessions; Z = 1.99, N = 8, P = 0.046). In addition almost all subjects recognized unknown individuals from different breeds, however with greater difficulty.

Conclusions/significance: Our results demonstrated that cattle have efficient individual recognition based on categorization capacities. Social familiarity improved their performance. The recognition of individuals with very different coat characteristics from the subjects was the most difficult task. These results call for studies exploring the mechanisms involved in face recognition allowing interspecies comparisons, including humans.

Show MeSH