Yawning is a common, species‐typical behaviour in vertebrates, generally associated with transitions from sleep to wakefulness. In primates, yawning occurs within a group in a variety of social contexts, suggesting that it has a communicative role, a hypothesis examined in this study. Yawning has rarely been studied. Quantitative studies have been concerned only with age, sex and social‐status differences in yawning frequency. The causation and function of yawning were examined in a quantitative, 796‐h ethological analysis of observations of two groups of Cercocebus albigena and one group of Macaca fascicularis. In both species, yawns occurred in two main contexts: during transitions from rest to activity (the ‘rest yawn’) and following social interactions (the ‘emotion yawn’). The rest yawn represents 90 % of yawns and is common to every age‐sex group. By contrast, the emotion yawn (10 %) is more frequent in adult males. Regardless of context, yawning was more frequent in males than females. Within males yawning frequency increased with age. Thus, sex hormones may modulate the physiological processes involved. Yawns were usually performed by individuals in seated, lying or standing positions. Yawns were frequently followed by short periods of rest, so that, when triggered by a social interaction, they occurred at its end. The morphology of the yawning act did not vary in regard to context age and/or sex of the yawner.

In apes, four criteria are set to explore referential and intentional communication: (1) successive visual orienting between a partner and distant targets, (2) the presence of apparent attention-getting behaviours, (3) the requirement of an audience to exhibit the behaviours, and (4) the influence of the direction of attention of an observer on the behaviours. The present study aimed at identifying these criteria in behaviours used by dogs in communicative episodes with their owner when their toy is out of reach, i.e. gaze at a hidden target or at the owner, gaze alternation between a hidden target and the owner, vocalisations and contacts. In this study, an additional variable was analysed: the position of the dog in relation to the location of the target. Dogs witnessed the hiding of a favourite toy, in a place where they could not get access to. We analysed how dogs engaged in communicative deictic behaviours in the presence of their owner; four heights of the target were tested. To control for the motivational effects of the toy on the dogs' behaviour and for the referential nature of the behaviours, observations were staged where only the toy or only the owner was present, for one of the four heights. The results show that gazing at the container and gaze alternation were used as functionally referential and intentional communicative behaviours. Behavioural patterns of dog position, the new variable, fulfilled the operational criteria for functionally referential behaviour and a subset of operational criteria for intentional communication: the dogs used their own position as a local enhancement signal. Finally, our results suggest that the dogs gazed at their owner at optimal locations in the experimental area, with respect to the target height and their owner's (or their own) line of gaze.

Objectives: To identify the causes of anaemia, other than acute blood loss, in dogs and to determine whether severity of anaemia provides clues to the diagnosis. Methods: The veterinary medical database of the Veterinary Campus Hospital, Lyon was searched. Dogs with anaemia (packed cell volume <37%) were included and assigned to different disease groups. Dogs with acute blood loss were excluded. The case records were examined for weakness at presentation, the severity and regeneration of anaemia and the final diagnosis including tumour type if applicable. Results: The case records of 456 dogs with low packed cell volume were included. Cancer‐related anaemia and anaemia of inflammatory disease accounted for 33·1 and 28·5% of cases, respectively. Most dogs with cancer‐related anaemia had solid tumours (73%). The prevalence of immune‐mediated anaemia increased with severity of anaemia (5·3, 15·5, 41·2 and 56·2% for mild, moderate, severe and very severe anaemia, respectively), whereas the prevalence of anaemia of inflammatory disease decreased (36·7, 22·5, 2·9 and 0% for mild, moderate, severe and very severe anaemia, respectively). Clinical Significance: Anaemia of inflammatory disease and cancer‐related anaemia were the most frequently identified causes of anaemia in dogs. The percentage of dogs with immune‐mediated anaemia increased with anaemia severity, whereas the percentage of dogs with anaemia of inflammatory disease decreased with anaemia severity. Thus, severity of anaemia may provide clues to the diagnosis.

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In order to characterize age-related cognitive changes, olfactory discrimination was assessed in Microcebus murinus, a prosimian primate. We compared young (n = 10) and old (n = 8) animals for individual performance on three olfactory tasks. Animals had to perform a detection, a transfer, and a reversal learning task using a go, no go conditioning procedure. No differences were observed between the two groups, indicating that aging is not inevitably associated with a decline in cognitive function. We did, however, observe two aged animals showing altered behavior. One animal displayed impairments in the reversal learning task, and the other showed impairments in both the transfer and reversal tasks. Transfer impairment may be due to a hippocampal alteration, whereas the perseverative tendency noted in the reversal task may be associated with frontal lobe dysfunction. Because some aged M. murinus display lesions that are pathognomonic of Alzheimer's disease, our observations highlight its potential utility as a primate model for studying cognitive deficits in relation to age and associated pathologies.

BackgroundIn 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 FindingsWe tested whether 8 Prim'Holstein heifers could recognize 2D-images of heads of one cow (face, profiles, ¾ 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/SignificanceOur 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.

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After reviewing the literature on current knowledge about consciousness in humans, we present a state-of-the art discussion on consciousness and related key concepts in animals. Obviously much fewer publications are available on non-human species than on humans, most of them relating to laboratory or wild animal species, and only few to livestock species. Human consciousness is by definition subjective and private. Animal consciousness is usually assessed through behavioural performance. Behaviour involves a wide array of cognitive processes that have to be assessed separately using specific experimental protocols. Accordingly, several processes indicative of the presence of consciousness are discussed: perception and cognition, awareness of the bodily-self, selfrelated knowledge of the environment (including social environment). When available, specific examples are given in livestock species. Next, we review the existing evidence regarding neuronal correlates of consciousness, and emphasize the difficulty of linking aspects of consciousness to specific neural structures across the phyla because high-level cognitive abilities may have evolved independently along evolution. Several mammalian brain structures (cortex and midbrain) are involved in the manifestations of consciousness, while the equivalent functional structures for birds and fishes would likely be the pallium/tectum and midbrain. Caution is required before excluding consciousness in species not having the same brain structures as the mammalian ones as different neural architectures may mediate comparable processes. Finally, specific neurophysiological mechanisms appear to be strongly linked to the emergence of consciousness, namely neural synchrony and neural feedback. Considering the limited amount of data available and the few animal species studied so far, we conclude that different manifestations of consciousness can be observed in animals but that further refinement is still needed to characterize their level and content in each species. Further research is required to clarify these issues, especially in livestock species.