Origins of domestic dog in southern East Asia is supported by analysis of Y-chromosome DNA

Global mitochondrial DNA (mtDNA) data indicates that the dog originates from domestication of wolf in Asia South of Yangtze River (ASY), with minor genetic contributions from dog-wolf hybridisation elsewhere. Archaeological data and autosomal single nucleotide polymorphism data have instead suggested that dogs originate from Europe and/or South West Asia but, because these datasets lack data from ASY, evidence pointing to ASY may have been overlooked. Analyses of additional markers for global datasets, including ASY, are therefore necessary to test if mtDNA phylogeography reflects the actual dog history and not merely stochastic events or selection. Here, we analyse 14,437 bp of Y-chromosome DNA sequence in 151 dogs sampled worldwide. We found 28 haplotypes distributed in five haplogroups. Two haplogroups were universally shared and included three haplotypes carried by 46% of all dogs, but two other haplogroups were primarily restricted to East Asia. Highest genetic diversity and virtually complete phylogenetic coverage was found within ASY. The 151 dogs were estimated to originate from 13-24 wolf founders, but there was no indication of post-domestication dog-wolf hybridisations. Thus, Y-chromosome and mtDNA data give strikingly similar pictures of dog phylogeography, most importantly that roughly 50% of the gene pools are shared universally but only ASY has nearly the full range of genetic diversity, such that the gene pools in all other regions may derive from ASY. This corroborates that ASY was the principal, and possibly sole region of wolf domestication, that a large number of wolves were domesticated, and that subsequent dog-wolf hybridisation contributed modestly to the dog gene pool.     

An Investigation on Social Representations: Inanimate Agent Can Mislead Dogs (Canis familiaris) in a Food Choice Task

The nature of mental representation of others plays a crucial role in social interactions. Dogs present an ideal model species for the investigation of such mental representations because they develop social ties with both conspecifics and heterospecifics. Former studies found that dogs’ preference for larger food quantity could be reversed by humans who indicate the smaller quantity. The question is whether this social bias is restricted to human partners. We suggest that after a short positive social experience, an unfamiliar moving inanimate agent (UMO) can also change dogs’ choice between two food quantities. We tested four groups of dogs with different partners: In the (1) Helper UMO and (2) Helper UMO Control groups the partner was an interactive remote control car that helped the dog to obtain an otherwise unreachable food. In the (3) Non-helper UMO and (4) Human partner groups dogs had restricted interaction with the remote control car and the unfamiliar human partners. In the Human partner, Helper UMO and Helper UMO Control groups the partners were able to revert dogs’ choice for the small amount by indicating the small one, but the Non-helper UMO was not. We suggest that dogs are able to generalize their wide range of experiences with humans to another type of agent as well, based on the recognition of similarities in simple behavioural patterns.     

Western Burrowing Owls (Athene cunicularia hypugaea) Eavesdrop on Alarm Calls of Black‐Tailed Prairie Dogs (Cynomys ludovicianus)

Animals sharing a common habitat can indirectly receive information about their environment by observing information exchanges between other animals, a process known as eavesdropping. Animals that use an auditory alarm calling system are an important indirect information source for eavesdropping individuals in their environments. We investigated whether Western burrowing owls (Athene cunicularia hypugaea) nesting on black‐tailed prairie dog (Cynomys ludovicianus) colonies responded to broadcasts of prairie dog alarm calls. Western burrowing owls are closely associated with black‐tailed prairie dogs in Colorado and neighboring states on the Great Plains of the United States. Prairie dog burrows in active colonies can serve as nesting sites for Western burrowing owls, and prairie dogs may act as an alternative prey source for predators, potentially decreasing the burrowing owls' risk of predation through the dilution effect. Burrowing owls nesting on prairie dog colonies may also eavesdrop on prairie dog alarm calls, enhancing their survival and nesting success on prairie dog colonies. We performed broadcast experiments with three different sounds: a prairie dog alarm call, a biological control (cattle mooing), and a non‐biological control (an airplane engine), and characterized burrowing owl responses as either alert or relaxed. For each sound stimulus, we recorded the time to first alert response to broadcast sounds (latency) and also how frequently the target burrowing owl exhibited an alert response within the first ten seconds of the broadcast (intensity). Burrowing owls reacted more quickly to the prairie dog alarm than to the biological control. They significantly increased the intensity of alert behaviors in response to broadcasts of the alarm, but did not show an increased reaction to either the biological or the non‐biological control. Our results suggest that burrowing owls nesting on prairie dog colonies eavesdrop on, and increase their alert behaviors in response to, prairie dog alarm calls.     

Owned and Unowned Dog Population Estimation,Dog Management and Dog Bites to Inform Rabies Prevention and Response on Lombok Island,Indonesia

Although Indonesia has been rabies-infected since at least the 1880s, some islands remain rabies-free, such as Lombok. However, due to its adjacency to rabies-infected islands such as Bali and Flores, there is considerable risk of a rabies incursion. As part of a rabies risk assessment project, surveys were conducted to estimate the size of the dog population and to describe dog management practices of households belonging to different ethnic groups. A photographic-recapture method was employed and the number of unowned dogs was estimated. A total of 400 dog owning households were interviewed, 300 at an urban site and 100 at a rural site. The majority of the interviewed households belonged to the Balinese ethnic group. Owned dogs were more likely male, and non-pedigree or local breed. These households kept their dogs either fully restricted, semi-free roaming or free-roaming but full restriction was reported only at the urban site. Dog bite cases were reported to be higher at the urban site, and commonly affected children/young adults to 20 years old and males. A higher number of unowned dogs was observed at the urban site than at the rural site. Data generated within these surveys can inform rabies risk assessment models to quantify the probability of rabies being released into Lombok and resulting in the infection of the local dog population. The information gained is critical for efforts to educate dog owners about rabies, as a component of preparedness to prevent the establishment of rabies should an incursion occur.     

A Survey of Dog Populations in Urban and Rural Areas of Yucatan,Mexico

ABSTRACT

A survey in a major Mexican city (Merida) and three rural communities was conducted to generate information regarding the size and structure of the owned-dog populations and people's opinions about the dogs and how they took care of them. Household characteristics and dog population size, health and reproductive issues were compared between the two kinds of communities: urban and rural. A telephone survey was conducted in Merida city whereas personal interviews were used in the rural communities. Local veterinarians were also interviewed to evaluate their influence on the dog populations in Merida city. The ratio of people to dogs was 3.4:1 in the city, and 1.7:1 to 4.6:1 in the different rural communities. In general it was more common to find a dog-owning household in the city of Merida (72.8%) than in the rural areas (63.6%, 65.5% and 71.1%), and in the city more households had adequate fences to restrain dogs. Larger families were more likely to own a dog than small families. Households of medium socio-economic status had a significantly higher probability of owning a dog than households of low or high socio-economic status. Of the dogs in the city, 90.1% were vaccinated against rabies compared with 62.3% of the dogs in the rural communities. Most animals were intact; the frequency of neutering/spaying was 3.1% in Merida and 1.8% in the rural communities. Few private veterinary practitioners were involved in the control of dog overpopulation. It is concluded that dogs are popular pets both in urban and rural Yucatan. People's opinions about dogs and the level of supervision varied with socio-economic status, and people in the city provided better food, shelter and preventive medicine. The veterinary practitioners did little to promote the control of dog breeding or to reduce the relinquishing of unwanted dogs in the city. Better client education and the promotion of sterilization of pets at low cost would improve the situation.     

Vocal behaviour in cattle: the animal's commentary on its biological processes and welfare

The vocalizations of cattle provide conspecifics with meaningful information about the caller. If we can learn how to interpret this information correctly, it could be used to improve management and welfare assessment. Vocalization may be viewed as a subjective commentary, by an individual, on its own internal state. The vocal behaviour of cattle is potentially a useful indicator of their physiological and psychological functioning.In the first part of this article we ask what information is exchanged using auditory cues. Vocalizations provide information on the age, sex, dominance status and reproductive status of the caller. Calves can recognize their mothers using vocal cues but it is not clear whether cows recognize their offspring in this way. Vocal behaviour may play a role in estrus advertisement and competitive display by bulls. Under experimental conditions involving pain or social isolation, vocal response is useful as an indicator of welfare, if properly used. Unlike commonly used physiological measures, it can be recorded non-invasively and varies on a number of quantitative and qualitative dimensions.In the second part we review methodological approaches to the study of vocal behaviour and their application in cattle welfare research. Methods may focus on the actions of the vocalizing animal and the conditions which elicit vocal behaviour, the response of an animal to hearing another's vocalizations, or interactions between sender and receiver.We argue that vocal behaviour in cattle may be valuable in welfare studies if the endogenous, exogenous and developmental factors influencing its expression can be more thoroughly investigated and understood.     

Characterization of variation in the canine suppressor of cytokine signaling-2 (SOCS2) gene

Suppressor of cytokine signaling 2 (SOCS2) is a negative regulator of growth hormone signaling. The deletion of SOCS2 in mice results in a 30-50% increase in post-natal growth. In an effort to identify polymorphisms in the SOCS2 gene that may be associated with body size in dogs, we characterized the canine SOCS2 gene and analyzed its genetic diversity among small and large dog breeds. The study was carried out on a total of 520 dogs from 66 different breeds. Dogs were classified as large or small based on height and weight as determined by their respective American Kennel Club breed standards. The SH2 and SOCS domains of the canine SOCS2 gene were sequenced in 32 dogs from different breeds. Only one non-synonymous sequence variant (DQ415457:g.326G>T) was detected which corresponds to an amino acid change (Asp127Tyr). All samples were genotyped by PCR/RFLP and the allele frequencies were determined for each dog breed. The T allele was distributed primarily among European large dog breeds with a gene frequency ranging from 0.72 to 0.04. The nature of the nucleotide change and the effect on the protein together with the finding of a QTL related to body size in the same CFA15 region by other researchers suggest canine SOCS2 as a potential candidate gene for body size in dogs. Future studies will be needed to clarify the role of the 326G>T polymorphism and its interaction with genes like growth hormone and insulin-like growth factor 1.     

Reading faces: differential lateral gaze bias in processing canine and human facial expressions in dogs and 4-year-old children

Sensitivity to the emotions of others provides clear biological advantages. However, in the case of heterospecific relationships, such as that existing between dogs and humans, there are additional challenges since some elements of the expression of emotions are species-specific. Given that faces provide important visual cues for communicating emotional state in both humans and dogs, and that processing of emotions is subject to brain lateralisation, we investigated lateral gaze bias in adult dogs when presented with pictures of expressive human and dog faces. Our analysis revealed clear differences in laterality of eye movements in dogs towards conspecific faces according to the emotional valence of the expressions. Differences were also found towards human faces, but to a lesser extent. For comparative purpose, a similar experiment was also run with 4-year-old children and it was observed that they showed differential processing of facial expressions compared to dogs, suggesting a species-dependent engagement of the right or left hemisphere in processing emotions.     

Anti-sperm antibodies and seminal characteristics after testicular biopsy or epididymal aspiration in dogs

A study was performed to determine if performing testicular biopsies or epididymal aspirates in dogs would induce sperm-bound anti-sperm antibodies (ASA), affect long-term sperm production or semen quality. Semen was collected from 8 mature dogs 3 times a week before and after hemicastration and then 3 times a week after testicular biopsy (n=3 and 1 control) or epididymal aspiration (n=3 and 1 control). Detection of anti-sperm IgG (ASA) on sperm cells was performed by flow cytometry analysis using a flow cytometer. Two dogs with testicular biopsies became positive for ASA 16 d after testicular biopsy and remained positive for 7 and 9 d, respectively. One dog that had an epididymal aspirate became positive 13 d after epididymal aspiration and remained positive for 35 d. One dog became positive 21 d after hemicastration and remained positive for 28 d. Sperm output declined significantly in 7 of 8 dogs after hemicastration. A control epididymal aspirate treatment dog had decreased sperm output, and a testicular biopsy treatment dog had increased sperm output. None of the dogs with ASA had significant changes in sperm output after treatment. Sperm motility declined significantly in 3 dogs after hemicastration. An epididymal aspiration treatment dog had a decrease in sperm motility, a control epididymal aspirate treatment dog and a control testicular biopsy treatment dog each had increases in sperm motility. None of the dogs with ASA had significant changes in motility. The percentage of normal spermatozoa significantly decreased in 3 dogs and significantly increased in 1 dog after hemicastration. Two dogs that had testicular biopsies and 1 dog that had an epididymal aspiration had decreases in percent normal sperm. Two of 3 dogs with decreases in percent normal sperm after treatment had ASA, but 2 dogs with ASA had no change in motility. Hemicastration, epididymal aspiration, and testicular biopsy can induce ASA production within 2 wk of the procedure, but ASA are transient and do not have a predictably negative effect on total sperm output or motility. Testicular biopsy and epididymal aspiration are safe diagnostic procedures, but further work investigating post-treatment fertility must be done before final conclusions can be made.     

The pet dogs ability for learning from a human demonstrator in a detour task is independent from the breed and age

There are many indications and much practical knowledge about the different tasks which various breeds of dogs are selected for. Correspondingly these different breeds are known to possess different physical and mental abilities. We hypothesized that commonly kept breeds will show differences in their problem solving ability in a detour task around a V-shaped fence, and also, that breed differences will affect their learning ability from a human demonstrator, who demonstrates a detour around the fence. Subjects were recruited in Hungarian pet dog schools. We compared the results of the 10 most common breeds in our sample when they were tested in the detour task without human demonstration. There was no significant difference between the latencies of detour, however, there was a trend that German Shepherd dogs were the quickest and Giant Schnauzers were the slowest in this test. For testing the social learning ability of dogs we formed three breed groups (“utility”, “shepherd” and “hunting”). There were no significant differences between these, all the breed groups learned equally well from the human demonstrator. However, we found that dogs belonging to the “shepherd” group looked back more frequently to their owner than the dogs in the “hunting” group. Further, we have found that the age of pet dogs did not affect their social learning ability in the detour task. Our results showed that the pet status of a dog has probably a stronger effect on its cognitive performance and human related behaviour than its age or breed. These results emphasize that socialization and common activities with the dog might overcome the possible breed differences, if we give the dogs common problem solving, or social learning tasks.     

The Effect of Priming on Perceptions of Dog Breed Traits

ABSTRACT

This study examined whether priming cues embedded in mediastyle presentations shaped people's perceptions of specific dog breeds, and in particular, the German shepherd dog (GSD). Two hundred and four adult females were exposed to one of two types of media-style presentation (stories or pictures). Half of the participants in each condition were exposed to versions designed to portray the GSD in a positive light; the remainder to stimuli developed to present the same breed in a negative light. Participants subsequently rated six individual breeds of dog, including the target breed, on a number of traits (e.g., “friendliness,” “aggression”). Analysis revealed a significant effect of priming on people's perceptions of the GSD. Participants exposed to the negative stimuli perceived this breed as significantly less approachable, and more dangerous and aggressive, than those exposed to the positive stimuli. Priming did not influence the participants' perceptions of other breeds, even those often regarded in a negative light, although there was some evidence of breed-related category-based stereotyping. Overall, results suggest that people's perceptions of dog breeds can be influenced by verbal and visual representations. The results have implications for how dogs are portrayed in the media and other publically available sources of information.     

The facilitation of social interactions by domestic dogs

Abstract

Research suggests that dogs can facilitate social interactions, which, in turn, may promote psychological health. This study explored the ability of dogs to facilitate social responses relative to other accompaniments and investigated whether the social catalysis effect is generic or influenced by the appearance of the dog. The behavior of 1800 pedestrians approaching a female experimenter was recorded as a function of the presence of three dogs (Labrador Retriever pup, Labrador adult, Rottweiler adult) and two neutral stimuli (teddy bear, potted plant). The behavior of pedestrians approaching the woman whenever she was alone (control) was also explored. Information was collected on the passers-by’ gender, number of people in the party, type of acknowledgement elicited and length of conversations. More people ignored the experimenter whenever she was alone or with the teddy or plant, than whenever she was walking a dog. The Rottweiler resulted in more nonresponses than the puppy or adult Labrador, who in turn elicited more smiles and verbal responses. Females, and those alone, elicited more smiles and conversations than males, or those in pairs. It is concluded that dogs can facilitate social interactions between adults better than other accompaniments; however, the social catalysis effect is not generic, but dog specific.     

Variation in Genes Related to Cochlear Biology Is Strongly Associated with Adult-Onset Deafness in Border Collies

Domestic dogs can suffer from hearing losses that can have profound impacts on working ability and quality of life. We have identified a type of adult-onset hearing loss in Border Collies that appears to have a genetic cause, with an earlier age of onset (3–5 years) than typically expected for aging dogs (8–10 years). Studying this complex trait within pure breeds of dog may greatly increase our ability to identify genomic regions associated with risk of hearing impairment in dogs and in humans. We performed a genome-wide association study (GWAS) to detect loci underlying adult-onset deafness in a sample of 20 affected and 28 control Border Collies. We identified a region on canine chromosome 6 that demonstrates extended support for association surrounding SNP Chr6.25819273 (p-value = 1.09×10⁻¹³). To further localize disease-associated variants, targeted next-generation sequencing (NGS) of one affected and two unaffected dogs was performed. Through additional validation based on targeted genotyping of additional cases (n = 23 total) and controls (n = 101 total) and an independent replication cohort of 16 cases and 265 controls, we identified variants in USP31 that were strongly associated with adult-onset deafness in Border Collies, suggesting the involvement of the NF-κB pathway. We found additional support for involvement of RBBP6, which is critical for cochlear development. These findings highlight the utility of GWAS–guided fine-mapping of genetic loci using targeted NGS to study hereditary disorders of the domestic dog that may be analogous to human disorders.     

Exploring the Relationship between Semantics and Space

The asymmetric distribution of human spatial attention has been repeatedly documented in both patients and healthy controls. Biases in the distribution of attention and/or in the mental representation of space may also affect some aspects of language processing. We investigated whether biases in attention and/or mental representation of space affect semantic representations. In particular, we investigated whether semantic judgments could be modulated by the location in space where the semantic information was presented and the role of the left and right parietal cortices in this task. Healthy subjects were presented with three pictures arranged horizontally (one middle and two outer pictures) of items belonging to the same semantic category. Subjects were asked to indicate the spatial position in which the semantic distance between the outer and middle pictures was smaller. Subjects systematically overestimated the semantic distance of items presented in the right side of space. We explored the neural correlates underpinning this bias using rTMS over the left and right parietal cortex. rTMS of the left parietal cortex selectively reduced this rightward bias. Our findings suggest the existence of an attentional and/or mental representational bias in semantic judgments, similar to that observed for the processing of space and numbers. Spatial manipulation of semantic material results in the activation of specialised attentional resources located in the left hemisphere.     

Why Do Large Dogs Sound More Aggressive to Human Listeners: Acoustic Bases of Motivational Misattributions

Previous research has highlighted that while human listeners are capable of estimating the body size of dogs using the acoustic components of their growls, they also rate growls from larger dogs as more being aggressive than growls from smaller dogs. The aim of this study was to investigate the relative contributions of two cues to body size, fundamental frequency (F0) and formant frequency dispersion (Δf) to perceived levels of aggression. We found that participants that had just made an accurate assessment of caller size based on these characteristics then misattributed aggressiveness levels on the basis of these same size‐related acoustic cues. More specifically, stimuli in which F0 and/or Δf were typical of larger dogs were rated as being more aggressive than stimuli typical of smaller dogs. Although both F0 and Δf influenced aggressiveness ratings independently, their interaction also had a significant affect. These results are discussed with respects to the human tendency to generalise reliable between‐class acoustic cues to within‐class stimuli and the resulting potential for making perceptual misattributions.     

CRANIAL MORPHOLOGY OF DOMESTIC AND WILD CANIDS: THE INFLUENCE OF DEVELOPMENT ON MORPHOLOGICAL CHANGE

The domestic dog varies remarkably in cranial morphology. In fact, the differences in size and proportion between some dog breeds are as great as those between many genera of wild canids. In this study, I compare patterns of intracranial allometry and morphologic diversity between the domestic dog and wild canid species. The results demonstrate that the domestic dog is morphologically distinct from all other canids except its close relatives, the wolf-like canids. Following this, I compare patterns of static and ontogenetic scaling. Data on growth of domestic dogs are presented and used to investigate the developmental mechanisms underlying breed evolution. Apparently, most small breeds are paedomorphic with respect to certain morphologic characters. In dogs and other domestic animals, morphologic diversity among adults seems to depend on that expressed during development.     

Exploration of Perceptions of Dog Bites among YouTube™ Viewers and Attributions of Blame

Dog bites are a human public health and dog welfare problem. This qualitative study is the first to use YouTube^? to examine how viewers perceive risk of, and attribute blame for, dog bites. Comments underneath 10 videos, chosen to represent a diversity of dog-bite scenarios, were analyzed inductively using thematic analysis. Six themes emerged: 1) Commentators thought that dogs are inherently good-natured but wild animals and emphasized how dogs try to avoid biting people; 2) all recognized breeds of dogs were stereotyped and breed stereotypes were used to shift the blame away from the dog and onto a bite victim, unless the dog identified in a video was a pit bull type. The dog was often blamed in such case; 3) It was argued that a breed limits the extent to which a dog can be trained and controlled; 4) Owners/handlers were often blamed for bites due to their inability to control the dog, and commentators identified the need for appropriate training and socialization in order to control dogs and reduce bite risk; 5) Bite victims were also blamed for the bites when their behavior was perceived as provoking a dog. Although children's behavior was identified as causing a risk, parents of children bitten in the videos were blamed for bites instead due to their approach to child supervision; 6) Bites in a range of contexts, such as play or when viewers thought that the victim's behavior provoked a dog, were seen as well-de-served and normal. It was concluded that although comments on publicly available videos need to be interpreted with caution due to a self-selection bias, their analysis can help to identify attitudes and perceptions towards risk around dogs that could aid bite prevention interventions and policies.     

Dog experts' brains distinguish socially relevant body postures similarly in dogs and humans

We read conspecifics' social cues effortlessly, but little is known about our abilities to understand social gestures of other species. To investigate the neural underpinnings of such skills, we used functional magnetic resonance imaging to study the brain activity of experts and non-experts of dog behavior while they observed humans or dogs either interacting with, or facing away from a conspecific. The posterior superior temporal sulcus (pSTS) of both subject groups dissociated humans facing toward each other from humans facing away, and in dog experts, a distinction also occurred for dogs facing toward vs. away in a bilateral area extending from the pSTS to the inferior temporo-occipital cortex: the dissociation of dog behavior was significantly stronger in expert than control group. Furthermore, the control group had stronger pSTS responses to humans than dogs facing toward a conspecific, whereas in dog experts, the responses were of similar magnitude. These findings suggest that dog experts' brains distinguish socially relevant body postures similarly in dogs and humans.     

The vocal repertoires of the bush dog (Speothos venaticus), crab-eating fox (Cerdocyon thous), and maned wolf (Chrysocyon brachyurus)

The vocalizations of the bush dog (Speothos venaticus), crab-eating fox (Cerdocyon thous), and maned wolf (Chrysocyon brachyurus) were studied in a captive setting. The three species' repertoires were similar and included whines, long-distance calls, and growls. The whines and growls varied in amplitude, duration, and repetition rate; these variations and the frequencies of occurrence probably were influenced by both social organization and habitat characteristics. The bush dog, which lives in family groups and inhabits rain forests, had an elaborate whine-scream continuum that at close distances conveyed a wide range of moods. On the other hand, the maned wolf, which is solitary and frequents open pampas, used amplitude variations of the growl to signal hostile intentions over short, medium, and long distances.The long-distance vocalizations of the three species were the least variable in structure; the bush dog and crab-eating fox used the call to promote contact with separated pairmates or family members. Based on recordings during development, these two calls appeared to arise from the repetitive whine, a variant of the basic whine syllable. The maned wolf also had a contact-promoting howl, apparently an extended whine of high amplitude, but it was rarely recorded during the present study. More prominent was the maned wolf roar-bark, which functioned to space individuals over large distances, and appeared to be a growl of high amplitude.     

Dogs discriminate between barks: The effect of context and identity of the caller

In the present study we explored whether dogs (Canis familiaris) are able to discriminate between conspecific barks emitted in different contexts recorded either from the same or different individuals. Playback experiments were conducted with dogs using barks as stimuli in a habituation–dishabituation paradigm. Barks were recorded in two contexts (stranger at the fence and when the dog was left alone) from different individuals. We found that dogs distinguished between barks emitted in these two contexts and were also able to discriminate between different individuals which were barking in the same context. These findings suggest that dog bark may carry context- and individual-specific information for the conspecifics.