|
Batt, L. S., Batt, M. S., Baguley, J. A., & McGreevy, P. D. (2009). The relationships between motor lateralization, salivary cortisol concentrations and behavior in dogs. Journal of Veterinary Behaviour, 4(6), 216–222.
Abstract: The degree of lateralization (LI) indicates both the direction and strength of a paw preference. Here, a positive value is indicative of a right paw bias, and a negative value of a left paw bias. Higher numbers on the positive side of the scale and lower numbers on the negative side of the scale indicate a greater strength of that lateralization. The strength of motor lateralization (|LI|) is the absolute value of the LI. The use of absolute value removes directionality (i.e., does not indicate left or right paw bias) and instead indicates only the strength of the paw preference. Both LI and |LI| have been associated with behavioral differences in a range of species. The assessment of motor lateralization in the dog can be conducted by observing the paw used to perform motor tasks. Elevated cortisol concentrations have been associated with fearfulness in many species. Additionally, fearfulness and boldness can be assessed in response to so-called temperament tests. Consequently, in this study we examine the relationship between lateralization, temperament test results, and cortisol concentrations in 43 potential guide dogs, of which 38 were Labrador retrievers and 5 were golden retrievers. Over a 14-month period, the current study assessed motor lateralization and salivary cortisol concentrations 3 times (approximately 6 months of age, 14 months of age, and after the dogs' performance in the guide dog program had been determined) and behavior twice (approximately 6 and 14 months of age). This study is the first to examine the relationship between behavior, lateralization, and cortisol concentrations in dogs. It implemented an objective and quantifiable assessment of behavior that may be of use to a variety of dog-focused stakeholders. Findings show that during the Juvenile testing period (6 months of age), dogs with higher cortisol concentrations were typically less able to rest when exposed to the unfamiliar testing room. Results from both Juvenile and Adult Test (14 months of age) periods showed that a greater |LI| and LI were associated with more confident and relaxed behavior when dogs were exposed to novel stimuli and unfamiliar environments. Significant elevations of cortisol concentrations were found at the completion of guide dog training when compared with results from the 2 prior test periods. This finding may reflect maturation or the effect of the prolonged kenneling which occurred during this period.
|
|
|
Milgram, N. W., Head, E., Muggenburg, B., Holowachuk, D., Murphey, H., Estrada, J., et al. (2002). Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy. Neurosci Biobehav Rev, 26(6), 679–695.
Abstract: The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition.
|
|
|
Jordan, J. (1970). [Modern views on the structure and function of the vomeronasal (Jacobson's) organ in mammals]. Otolaryngol Pol, 24(4), 457–462.
|
|
|
Giangaspero, A., Traversa, D., & Otranto, D. (2004). [Ecology of Thelazia spp. in cattle and their vectors in Italy]. Parassitologia, 46(1-2), 257–259.
Abstract: The genus Thelazia (Spirurida, Thelaziidae) includes a cosmopolitan group of eyeworm spirurids responsible for ocular infections in domestic and wild animals and transmitted by different species of muscids. Bovine thelaziosis is caused by Thelazia rhodesi Desmarest 1828, Thelazia gulosa Railliet & Henry 1910, and Thelazia skrjabini Erschow 1928, which occur in many countries; T. gulosa and T. skrjabini have been reported mainly in the New World, while T. rhodesi is particularly common in the Old World. In Italy, T. rhodesi was reported in southern regions a long time ago and, recently, T. gulosa and T. skrjabini have been identified in autochthonous cattle first in Apulia and then in Sardinia. Thirteen species of Musca are listed as intermediate hosts of eyeworms, but only Musca autumnalis and Musca larvipara have been demonstrated to act as vectors of Thelazia in the ex-URSS, North America, ex-Czechoslovakia and more recently in Sweden. In Italy, after the reports of T. gulosa and T. skrjabini in southern regions, the intermediate hosts of bovine eyeworms were initially only suspected as the predominant secretophagous Muscidae collected from the periocular region of cattle with thelaziosis were the face flies, M. autumnalis and M. larvipara, followed by Musca osiris, Musca tempestiva and Musca domestica. The well-known constraints in the identification of immature eyeworms to species by fly dissection and also the time-consuming techniques used constitute important obstacles to epidemiological field studies (i.e. vector identification and/or role, prevalence and pattern of infection in flies, etc.). Molecular studies have recently permitted to further investigations into this area. A PCR-RFLP analysis of the ribosomal ITS-1 sequence was developed to differentiate the 3 species of Thelazia (i.e. T. gulosa, T. rhodesi and T. skrjabini) found in Italy, then a molecular epidemiological survey has recently been carried out in field conditions throughout five seasons of fly activity and has identified the role of M. autumnalis, M. larvipara, M. osiris and M. domestica as vectors of T. gulosa and of M. autumnalis and M. larvipara of T. rhodesi. Moreover, M. osiris was described, for the first time, to act as a vector of T. gulosa and M. larvipara of T. gulosa and T. rhodesi. The mean prevalence in the fly population examined was found to be 2.86%. The molecular techniques have opened new perspectives for further research on the ecology and epidemiology not only of Thelazia in cattle but also of other autochthonous species of Thelazia which have been also recorded in Italy, such as Thelazia callipaeda, which is responsible for human and canid ocular infection and Thelazia lacrymalis, the horse eyeworm whose epidemiological molecular studies are in progress.
|
|
|
Siniscalchi, M., McFarlane, J. R., Kauter, K. G., Quaranta, A., & Rogers, L. J. (2013). Cortisol levels in hair reflect behavioural reactivity of dogs to acoustic stimuli. Research in Veterinary Science, 94(1), 49–54.
Abstract: Cortisol levels in hair samples were examined in fourteen domestic dogs and related to the dogs’ responses to different acoustic stimuli. Stimuli were playbacks of species-typical vocalizations recorded during three different situations (“disturbance”, “isolation” and “play” barks) and the sounds of a thunderstorm. Hair samples were collected at 9:00 h and 17:00 h two weeks after the behavioural tests. Results showed that behavioural reactivity to playback of the various stimuli correlates with cortisol levels in hair samples collected at 9:00 h, and the same was the case for the separate measures of behaviour (i.e. hiding, running away, seeking attention from the tester, panting and lowering of the body posture). Hence, levels of cortisol in hair appear to reflect the dog’s chronic state of emotional reactivity, or temperament.
|
|
|
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
|
|
|
Bloom, P. (2004). Behavior. Can a dog learn a word? Science, 304(5677), 1605–1606.
|
|
|
Hare, B., Brown, M., Williamson, C., & Tomasello, M. (2002). The domestication of social cognition in dogs. Science, 298(5598), 1634–1636.
Abstract: Dogs are more skillful than great apes at a number of tasks in which they must read human communicative signals indicating the location of hidden food. In this study, we found that wolves who were raised by humans do not show these same skills, whereas domestic dog puppies only a few weeks old, even those that have had little human contact, do show these skills. These findings suggest that during the process of domestication, dogs have been selected for a set of social-cognitive abilities that enable them to communicate with humans in unique ways.
|
|
|
Pennisi, E. (2006). Animal cognition. Man's best friend(s) reveal the possible roots of social intelligence (Vol. 312).
|
|
|
Straub, A. (2007). An intelligent crow beats a lab. Science, 316(5825), 688.
|
|