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West, R. E., & Young, R. J. (2002). Do domestic dogs show any evidence of being able to count? Anim. Cogn., 5(3), 183–186.
Abstract: Numerical competence has been demonstrated in a wide range of animal species. The level of numerical abilities shown ranges from simple relative numerousness judgements to true counting. In this study we used the preferential looking technique to test whether 11 pet dogs could count. The dogs were presented with three simple calculations: “1+1=2”; “1+1=1”; and “1+1=3”. These calculations were performed by presenting the dogs with treats that were placed behind a screen that allowed manipulation of the outcome of the calculation. When the dogs expected the outcome they spent the same amount of time looking at the result of the calculation as they did on the initial presentation. However, when the result was unexpected dogs spent significantly longer looking at the outcome of the calculation. The results suggest that the dogs were anticipating the outcome of the calculations they observed, thus suggesting that dogs may have a rudimentary ability to count.
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Goncalves, T. C., Rocha, D. S., & Cunha, R. A. (2000). Feeding patterns of Triatoma vitticeps in the State of Rio de Janeiro, Brazil. Rev Saude Publica, 34(4), 348–352.
Abstract: OBJECTIVE: Feeding patterns of triatomines have contributed to elucidate its biology. Triatoma vitticeps, naturally infected with T. cruzi, has been found in domiciles. Its behavior and epidemiological patterns were investigated. METHODS: One-hundred and twenty two specimens of T. vitticeps were captured from February 1989 to April 1993 in two areas of Triunfo municipality, a subdistrict of Santa Maria Madalena municipal district, State of Rio de Janeiro, Brazil. The insects were dissected and their intestinal contents were removed and tested. It was used antisera from: man, cow, horse, dog, pig, armadillo, opossum, rodent, and bird. RESULTS: From the total analyzed, 79 were positive and 43 were negative to the nine antisera tested: armadillo (30.3%) > human and pig (13.1%) > bird and dog (11.5%) > horse (5.7%) > opossum (4.9%) > rodent (4. 1%) > cow (3.3%). Blood meals ranged from 0 to 4 and 6 in the following distribution: 0 = 25.41%; 1 = 45.08%; 2 = 10.66%; 3 = 6. 56%; 4 = 1.64%, and 6 = 0.82%. Nine of the 122 insects captured were not examined, 74 (65.54%) were positive for T. cruzi infection and 39 (34.51%) were negative. CONCLUSIONS: These results identified the T. vitticeps as being a sylvatic species and trypanosomiasis as being an enzootic disease. Epidemiological vigilance will be important to provide more information regarding the behavior of the species
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Soproni, K., Miklósi, A., Topál, J., & Csányi, V. (2001). Comprehension of human communicative signs in pet dogs (Canis familiaris). J Comp Psychol, 115(2), 122–126.
Abstract: On the basis of a study by D. J. Povinelli, D. T. Bierschwale, and C. G. Cech (1999), the performance of family dogs (Canis familiaris) was examined in a 2-way food choice task in which 4 types of directional cues were given by the experimenter: pointing and gazing, head-nodding (“at target”), head turning above the correct container (“above target”), and glancing only (“eyes only”). The results showed that the performance of the dogs resembled more closely that of the children in D. J. Povinelli et al.'s study, in contrast to the chimpanzees' performance in the same study. It seems that dogs, like children, interpret the test situation as being a form of communication. The hypothesis is that this similarity is attributable to the social experience and acquired social routines in dogs because they spend more time in close contact with humans than apes do, and as a result dogs are probably more experienced in the recognition of human gestures.
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Tomkins, L. M., McGreevy, P. D., & Branson, N. J. (2010). Lack of standardization in reporting motor laterality in the domestic dog (Canis familiaris). Journal of Veterinary Behaviour, 5(5), 235–239.
Abstract: Over the past 2 decades, numerous studies have been undertaken to assess motor laterality in the domestic dog. In anticipation of growth in this area of enquiry, we decided to review the literature on canine motor biases to identify any shortcomings, reflect on the lessons to be learned from and offer ways forward for future research into canine laterality. The aim of this review is to (i) summarize motor laterality findings in the dog, (ii) highlight areas lacking in standardization, and (iii) propose necessary criteria for future tests and global reporting protocols. Our review of the literature highlighted the lack of standardization between studies in task selection, sample size, number of behavior scores recorded, and the methods by which motor laterality were classified and reported. This review illustrates the benefits of standardizing methods of motor laterality assessment so that comparisons can be made between the populations sampled. By adopting such an approach, researchers should mutually benefit as motor laterality data could then be compared and subjected to meta-analysis.
Keywords: dog; motor laterality; lateralization; paw preference; standardization
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Quaranta, A., Siniscalchi, M., Frate, A., & Vallortigara, G. (2004). Paw preference in dogs: relations between lateralised behaviour and immunity. Behavioural Brain Research, 153(2), 521–525.
Abstract: Paw use in a task consisting of the removal of a piece of adhesive paper from the snout was investigated in 80 mongrel and pure-bred domestic dogs (Canis familiaris). Population lateralisation was observed, but in opposite directions in the two sexes (animals were not desexed): males preferentially used their left paw, females their right paw. The relationship between immune function and paw preference was then investigated. Some immune parameters (total number of white blood cells including lymphocytes, granulocytes and monocytes; leukocyte formula; total proteins; γ-globulins) were investigated in a sample of left-pawed (n=6), right-pawed (n=6) and ambidextrous (n=6) dogs. The results showed that the percentage of lymphocytes was higher in left-pawed than in right-pawed and ambidextrous dogs, whereas granulocytes percentage was lower in left-pawed than in right-pawed and ambidextrous dogs. Moreover, total number of lymphocytes cells was higher in left-pawed than in right-pawed and ambidextrous dogs, whereas the number of γ-globulins was lower in left-pawed than in right-pawed and ambidextrous dogs. These findings represent the first evidence that brain asymmetry modulates immune responses in dogs.
Keywords: Paw preference; Lateralisation; Immunity; Dog
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Bräuer, J., Call, J., & Tomasello, M. (2004). Visual perspective taking in dogs (Canis familiaris) in the presence of barriers. Appl. Anim. Behav. Sci., 88(3-4), 299–317.
Abstract: Previous studies have shown that dogs have developed a special sensitivity to the communicative signals and attentional states of humans. The aim of the current study was to further investigate what dogs know about the visual perception of humans and themselves. In the first two experiments we investigated whether dogs were sensitive to the properties of barriers as blocking the visual access of humans. We presented dogs with a situation in which a human forbade them to take a piece of food, but the type and orientation of the barrier allowed the dog to take the food undetected in some conditions. Dogs differentiated between effective and ineffective barriers, based on their orientation or the particular features of the barriers such as size or the presence of window. In the third study we investigated whether dogs know about what they themselves have seen. We presented subjects with two boxes and placed food in one of them. In the Seen condition the location of the food was shown to the dogs while in the Unseen condition dogs were prevented from seeing the destination of the food. Before selecting one of the boxes by pressing a lever, dogs had the opportunity to seek extra information regarding the contents of the boxes, which would be particularly useful in the condition in which they had not seen where the food was hidden. Dogs rarely used the opportunity to seek information about the contents of the box before making their choice in any condition. Therefore, we found no evidence suggesting that dogs have access to what they themselves have seen, which contrasts with the positive evidence about visual perspective taking in others from the first two experiments and previous studies.
Keywords: Dogs; Visual perspective taking; Metacognition
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Fiset, S., & Leblanc, V. (2007). Invisible displacement understanding in domestic dogs (Canis familiaris): the role of visual cues in search behavior. Anim. Cogn., 10(2), 211–224.
Abstract: Recently, (Collier-Baker E, Davis JM, Suddendorf T (2004) J Comp Psychol 118:421-433) suggested that domestic dogs do not understand invisible displacements. In the present study, we further investigated the hypothesis that the search behavior of domestic dogs in invisible displacements is guided by various visual cues inherent to the task rather than by mental representation of an object's past trajectory. Specifically, we examined the role of the experimenter as a function of the final position of the displacement device in the search behavior of domestic dogs. Visible and invisible displacement problems were administered to dogs (N = 11) under two conditions. In the Visible-experimenter condition, the experimenter was visible whereas in the Concealed-experimenter condition, the experimenter was visibly occluded behind a large rigid barrier. Our data supported the conclusion that dogs do not understand invisible displacements but primarily search as a function of the final position of the displacement device and, to a lesser extent, the position of the experimenter.
Keywords: Animals; Dogs/*physiology; Female; Male; *Space Perception; *Spatial Behavior; *Visual Perception
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Dreschel, N. A., & Granger, D. A. (2009). Methods of collection for salivary cortisol measurement in dogs. Horm. Behav., 55(1), 163–168.
Abstract: Salivary cortisol has been increasingly used as a measure of stress response in studies of welfare, reaction to stress and human–animal interactions in dogs and other species. While it can be a very useful measure, there are a number of saliva collection issues made evident through studies in the human and animal fields which have not been investigated in the canine species. Collection materials and the volume of saliva that is collected; the use of salivary stimulants; and the effect of food contamination can all dramatically impact cortisol measurement, leading to spurious results. In order to further examine the limitations of the collection method and the effects of collection material and salivary stimulant on salivary cortisol levels, a series of clinical, in vitro and in vivo studies were performed. It was found that there is a large amount of inter- and intra-individual variation in salivary cortisol measurement. Beef flavoring of collection materials leads to unpredictable variability in salivary cortisol concentration. Using salivary stimulants such as citric acid also has the potential to affect cortisol concentration measurement in saliva. Hydrocellulose appears to be a useful collection material for salivary cortisol determination. Recommendations for collection materials and use of salivary stimulants are presented.
Keywords: Dog; Canine; Salivary cortisol; Methods; Measurement; Stress
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Tomkins, L. M., Williams, K. A., Thomson, P. C., & McGreevy, P. D. (2010). Sensory Jump Test as a measure of sensory (visual) lateralization in dogs (Canis familiaris). Journal of Veterinary Behavior, 5(5), 256–267.
Abstract: Sensory lateralization in dogs (n = 74) was investigated in this study using our innovation, the Sensory Jump Test. This required the modification of head halters to create three different ocular treatments (binocular, right, and left monocular vision) for eye preference assessment in a jumping task. Ten jumps were recorded as a jump set for each treatment. Measurements recorded included (i) launch and landing paws, (ii) type of jump, (iii) approach distance, (iv) clearance height of the forepaw, hindpaw, and the lowest part of the body to clear the jump, and (v) whether the jump was successful. Factors significantly associated with these jump outcomes included ocular treatment, jump set number, and replication number. Most notably, in the first jump set, findings indicated a left hemispheric dominance for the initial navigation of the Sensory Jump Test, as left monocular vision (LMV) compromised of jumping more than right monocular (RMV) and binocular vision, with a significantly reduced approach distance and forepaw clearance observed in dogs with LMV. However, by the third jump set, dogs undergoing LMV launched from a greater approach distance and with a higher clearance height, corresponding to an increase in success rate of the jump, in comparison with RMV and binocular vision dogs. A marginally non-significant RMV bias was observed for eye preference based on the laterality indices for approach distance (P = 0.060) and lowest body part clearance height (P = 0.067). A comparison between eye preference and launching or landing paws showed no association between these measures of sensory and motor laterality. To our knowledge, this is the first study to report on sensory lateralization in the dog, and furthermore, to compare both motor and sensory laterality in dogs.
Keywords: sensory lateralization; monocular vision; binocular vision; jump kinematics; dog
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Schwab, C., & Huber, L. (2006). Obey or not obey? Dogs (Canis familiaris) behave differently in response to attentional states of their owners. J Comp Psychol, 120(3), 169–175.
Abstract: Sixteen domestic dogs (Canis familiaris) were tested in a familiar context in a series of 1-min trials on how well they obeyed after being told by their owner to lie down. Food was used in 1/3 of all trials, and during the trial the owner engaged in 1 of 5 activities. The dogs behaved differently depending on the owner's attention to them. When being watched by the owner, the dogs stayed lying down most often and/or for the longest time compared with when the owner read a book, watched TV, turned his or her back on them, or left the room. These results indicate that the dogs sensed the attentional state of their owners by judging observable behavioral cues such as eye contact and eye, head, and body orientation.
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