Canine hyper-sociability structural variants associated with altered three-dimensional chromatin state.

Strong selection on complex traits can lead to skewed trait means and reduced trait variability in populations. An example of this phenomenon can be evidenced in allele frequency changes and skewed trait distributions driven by persistent human-directed selective pressures in domesticated species. Dog domestication is linked to several genomic variants; however, the functional impacts of these variants may not always be straightforward when found in non-coding regions of the genome. Four polymorphic transposable elements (TE) found within non-coding sites along a 5 Mb region on canine CFA6 have evolved due to directional selection associated with heightened human-directed hyper-sociability in domesticated dogs. We found that the polymorphic TE in intron 17 of the canine GTF2I gene, which was previously reported to be negatively correlated with canid human-directed hyper-sociability, is associated with altered chromatin looping and hence distinct cis-regulatory landscapes. We reported supporting evidence of an E2F1-DNA binding peak concordant with the altered loop and higher expression of GTF2I exon 18, indicative of alternative splicing. Globally, we discovered differences in pathways regulating the extra-cellular matrix with respect to TE copy number. Overall, we reported evidence suggesting an intriguing molecular convergence between the emergence of hypersocial behaviors in dogs and the same genes that, when hemizygous, produce human Williams Beuren Syndrome characterized by cranio-facial defects and heightened social behaviors. Our results additionally emphasize the often-overlooked potential role of chromatin architecture in social evolution.

The behavioural effect of short-term cognitive and physical intervention therapies in old dogs.

Efforts to counteract age-related decline have resulted in the emergence of various interventions. However, everyday benefits are rarely reported in elderly people. Dogs provide an excellent model for studying aging and interventions due to their similarities to humans. Our aim was to investigate whether a combined physical and cognitive intervention (most effective in humans) could enhance the performance of pet dogs and lead to far transfer effects (improvement in not just the trained specific task). We examined the impact of three-month-long intervention therapies (cognitive, physical, combined) on the cognitive performance and behaviour of old, healthy dogs (N = 72; aged 7.68-14.54 years) using a 12-subtest behavioural test battery. We did not find the combined intervention group outperforming either the cognitive-only or physical-only therapy groups. Physical interventions, either alone or in combination, improved dogs' behavioural flexibility and social behaviour. Cognitive interventions, either alone or in combination, increased neophilia. Furthermore, all intervention therapies made dogs more engaged with their environment. Moreover, less old, around eight years old dogs, exhibited improved social behaviour, problem solving ability, and increased neophilia by their second test occasion. Additionally, dogs' performance was influenced by their health, training, daily play with the owner, and activity/excitability traits. In sum, both cognitive and physical intervention therapies can have an impact on the behaviour of old, healthy pet dogs. However, these therapies may be more effective when longer or applied at a younger age, as the healthy older dogs were less likely to show improvement.

Cognitive and sensory capacity each contribute to the canine spatial bias.

Dogs interpret cues as being about location, which human infants would relate to objects. This spatial bias could shed light on the evolution of object-centered thought, however, research needs to rule out that this is not a by-product of dogs' weaker (compared to humans) visual capacities. In this study, we used a data set in which dogs were tested in two types of learning tasks (discrimination and reversal learning) with two types of rewarded cues (location and object features). In both tasks, dogs displayed spatial bias, that is, faster learning when the rewarded cue was a location. We investigated how sensory and cognitive capacity each contributes to this spatial bias. To this end, an estimate for general cognitive ability (g) was obtained from a battery of tests for some of the dogs. Cephalic index, a feature targeted in breeding and linked to differences in visual capacity, correlated negatively with the expression of spatial bias only in the easier discrimination learning task, while a negative correlation between g factor and spatial bias scores emerged in the more difficult reversal learning task. We conclude that dogs' spatial bias cannot be reduced to a sensory limitation and is easier to overcome with greater cognitive capacity.

Cross-sectional United Kingdom surveys demonstrate that owners and veterinary professionals differ in their perceptions of preventive and treatment healthcare needs in ageing dogs.

Perceptions of dog owners and veterinary professionals (surgeons/nurses) can influence the preventive healthcare and treatment provided to dogs, especially at the senior life-stage, when chronic diseases become more common. This study compared perceptions of healthcare of dogs as they age between dog owners and veterinary professionals. Data from two online surveys (owners: N = 633, veterinary professionals: N = 305) examined perceived need for veterinary visits and vaccinations. In addition, 48 clinical signs were rated on perceived prevalence (whether owners' dogs had experienced them) and how urgently they should seek veterinary advice. Groups were compared using descriptive statistics and chi-square. Owners most often believed a 'healthy' senior dog (>7 years) should go to the vet once a year (47% owners vs. 25% veterinary professionals, p < 0.001), compared with veterinary professionals every 6 months (39 vs. 73%). A minority (14%) of owners would just take the dog 'if they got sick' but only 2% of veterinary professionals advised this, and 16% of owners of dogs of all ages had not had any contact with their veterinary practise in the previous year. Nearly all veterinary professionals (92%) believed that senior/geriatric dogs should receive yearly vaccinations. However, 28% of owners' dogs of all ages were not vaccinated in the previous year and, of these, 33% did not believe that older dogs need vaccinations. Only 10% of dogs considered 'old' by their owners had attended a senior wellness clinic or examination, despite 14% of practises offering them. The three most common clinical signs reported by owners were slowing down on walks (57%), dental tartar (53%) and being stiff on rising (50%). Owners perceived urgency to seek veterinary care was lower if they had experienced the clinical sign before. In the current study, dog owners and veterinary professionals differed in their opinions about the need for veterinary care, suggesting new educational initiatives, and more effective communication is required.

Age-related effects on a hierarchical structure of canine cognition.

The current study investigates whether there are statistically independent age-related influences on the canine cognitive structure and how individual factors moderate cognitive aging on both cross-sectional and longitudinal samples. A battery of seven tasks was administered to 129 pet dogs, on which exploratory and confirmatory factor analyses were employed to unveil the correlational structure underlying individual differences in cognitive performance. The best-fitting model featured a hierarchical structure with two first-order cognitive domains (individual problem solving, learning) and a second-order common factor. These higher order factors exhibited consistency over a period of at least 2.5 years. External validation linked the common factor positively to discrimination and reversal learning performance, exploration, neophilia, activity/excitability, and training level while negatively to cognitive dysfunction symptoms, suggesting that it is a good candidate for a general cognitive factor (canine g). Structural equation models identified three distinct age-related influences, operating on associative learning, on memory, and on canine g. Health status moderated the negative age-canine g relationship, with a stronger association observed in dogs with poorer health status, and no relationship for dogs in good health. On a longitudinal sample (N = 99), we showed that the direction and magnitude of change in canine g over up to 3 years is affected by various interactions between the dogs' age, communication score, baseline performance, and time elapsed since the baseline measurement. These findings underscore the presence of a general cognitive factor in dogs and reveal intriguing parallels between human and canine aging, affirming the translational value of dogs in cognition and aging research.

Success in the Natural Detection Task is influenced by only a few factors generally believed to affect dogs' olfactory performance.

Research into dogs' olfactory ability is growing rapidly. However, generalising based on scientific results is challenging, because research has been typically conducted on a few specially trained subjects of a few breeds tested in different environmental conditions. We investigated the effects of temperature and humidity (outdoors), age, test location, sex, neutering status, and repeated testing (outdoors and indoors) on the olfactory performance of untrained family dogs (N = 411) of various breeds. We employed the Natural Detection Task with three difficulty levels, from which we derived two performance metrics: Top Level and Success Score. Temperature (0-25 °C) and humidity (18-90%) did not affect olfactory performance. Young adult dogs surpassed other age groups in reaching the Top Level. Sex and neutering status showed no discernible influence on Top Level and Success Score. Dogs performed better in both metrics when tested indoors compared to outdoors. In the test-retest procedure no significant learning effect was observed. We confirmed on untrained companion dogs that olfactory performance declines with age and rejected some factors that have been previously hypothesised to significantly affect dogs' olfactory success. The influence of the testing environment was notable, emphasising the need to consider various factors in understanding dogs' olfactory capabilities.

High-resolution computed tomographic (HRCT) image series from 413 canid and 18 felid skulls.

Computed tomography (CT) is a non-invasive, three-dimensional imaging tool used in medical imaging, forensic science, industry and engineering, anthropology, and archaeology. The current study used high-resolution medical CT scanning of 431 animal skulls, including 399 dog skulls from 152 breeds, 14 cat skulls from 9 breeds, 14 skulls from 8 wild canid species (gray wolf, golden jackal, coyote, maned wolf, bush dog, red fox, Fennec fox, bat-eared fox), and 4 skulls from 4 wild felid species (wildcat, leopard, serval, caracal). This comprehensive and unique collection of CT image series of skulls can provide a solid foundation not only for comparative anatomical and evolutionary studies but also for the advancement of veterinary education, virtual surgery planning, and the facilitation of training in sophisticated machine learning methodologies.