Background: Obsessive-compulsive disorder (OCD), a severe mental disease manifested in time-consuming repetition of behaviors, affects 1 to 3% of the human population. While highly heritable, complex genetics has hampered attempts to elucidate OCD etiology. Dogs suffer from naturally occurring compulsive disorders that closely model human OCD, manifested as an excessive repetition of normal canine behaviors that only partially responds to drug therapy. The limited diversity within dog breeds makes identifying underlying genetic factors easier. Results: We use genome-wide association of 87 Doberman Pinscher cases and 63 controls to identify genomic loci associated with OCD and sequence these regions in 8 affected dogs from high-risk breeds and 8 breed-matched controls. We find 119 variants in evolutionarily conserved sites that are specific to dogs with OCD. These case-only variants are significantly more common in high OCD risk breeds compared to breeds with no known psychiatric problems. Four genes, all with synaptic function, have the most case-only variation: neuronal cadherin (CDH2), catenin alpha2 (CTNNA2), ataxin-1 (ATXN1), and plasma glutamate carboxypeptidase (PGCP). In the 2 Mb gene desert between the cadherin genes CDH2 and DSC3, we find two different variants found only in dogs with OCD that disrupt the same highly conserved regulatory element. These variants cause significant changes in gene expression in a human neuroblastoma cell line, likely due to disrupted transcription factor binding. Conclusions: The limited genetic diversity of dog breeds facilitates identification of genes, functional variants and regulatory pathways underlying complex psychiatric disorders that are mechanistically similar in dogs and humans.
2 October 2018 in Journal of Applied Animal Welfare Science
Currently, there has been growing attention to animal welfare in animal-assisted interventions (AAI). However, there is a lack of scrutiny regarding what steps to take to ensure animal wellbeing during AAI research. The Institutional Animal Care and Use Committee (IACUC) reviews, monitors, and approves all research involving animal subjects in order to ensure an animal's ethical and humane treatment. However, AAI publications rarely report IACUC approval. The purpose of this critical review was to determine the frequency of IACUC approval and to report the descriptions of animal use in AAI research publications. In the 139 articles reviewed, 14 (10%) studies reported attaining IACUC approval; 4/139 (3%) reported an adverse outcome on at least one animal used in the study. The publications inconsistently reported the training or certification and veterinary care of the animals. Lacking IACUC approval in AAI studies indicates that the field underutilizes this method of monitoring animal health and welfare. The IACUC should assess, approve, and monitor research protocols involving animals prior to conducting every study to safeguard AAI animal welfare.
Object play occurs in diverse animals in addition to birds and mammals. Although many carnivores engage in object play in a predatory context, many non-predators do so also. Conjectures over the years on the motivation to play are reviewed dealing with intrinsic, developmental, and stimulus factors. We then report on quantitative studies of the play of puppies from 6 litters (3 breeds) when given 5 different toys with different sensory and functional properties at half week intervals from 3 to 7 weeks of age. The propensity to engage with objects begins early, play complexity increases rapidly, the structure of the play is similar to adult object play, and breed differences were found. Object play with predatory characteristics appears before weaning, suggesting that hunger is not the primary motivation. Studying the development of object play in different dog breeds may be useful in addressing questions of domestication and play evolution.
Background: Previous studies in human patients suggest depth of sedation may be affected by environmental noise or music; however, related data in domestic animals is limited. The objective of the current study was to investigate the effect of noise and music on dexmedetomidine-induced (DM- 10 µg/kg, IM) sedation in 10 dogs.Methods: In a crossover design, post-DM injection dogs were immediately subjected to recorded human voices at either 55–60 decibel (dB) (Noise 1) or 80–85 dB (Noise 2); classical music at 45–50 dB (Music); or background noise of 40–45 dB (Control+). Control− included IM saline injection and exposure to 40–45 dB background noise. Sedation was assessed via monitoring spontaneous behavior and accelerometry (delta-g) throughout three 20-min evaluation periods: baseline, noise exposure, and post-treatment. Sedation was further assessed during two restraint tests at 30 min (R1) and 40 min (R2) post-injection. A mixed model for crossover design was used to determine the effect of noise exposure and time on either spontaneous behavior scores or delta-g. The restraint scores were analyzed using a two-way repeated measures ANOVA.Results: Spontaneous behavior scores indicated less sedation during Noise 2 compared to Control+ (P = 0.05). R2 restraint scores for all DM treatments except Noise 2 indicated significantly higher sedation than Control− [C+ (P = 0.003), M (P = 0.014) and N1 (P = 0.044)].Discussion: Results suggest that the quality of sedation is negatively impacted by high-intensity noise conditions (80–85 dB), but exposure to music did not improve sedation in this population of research dogs.
The purpose of this retrospective case study was to evaluate trends over time in case distribution, sources, and breeds of dogs presenting to the behavioral medicine service at a veterinary college referral hospital in the United States. For case distribution and sources, the available records from the behavior service (n = 1923) from 1997 to 2017 were evaluated. Breeds of dogs presenting to all services (n = 51,052) were compared to behavior cases (n = 822) from 2007 to 2016. Over twenty years, 72.2% of dogs presented for aggression, 20.1% for anxieties/fears/phobias, and 7.4% for miscellaneous behavioral problems. Dogs acquired from breeders decreased and dogs from shelters, rescues, or adopted as a stray increased over twenty years (p < 0.0001). The Herding (p = 0.0124) and Terrier (p < 0.0001) groups were overrepresented for behavior problems as compared to all other services over ten years. Variations in terminology and diagnostic approach made comparisons with earlier studies difficult, which underscores a need for a more consistent methodology in veterinary behavioral medicine. Understanding trends in sources of dogs could direct resources aimed at guiding owners when acquiring a pet dog and preventing behavioral problems. Findings related to breeds could help guide research focused on the genetic contributions to behavior.
Dog and cat preference has been associated with a few factors, like owner personality traits, but data regarding other aspects of preference ontogeny and the impact of preferences on pet wellbeing have yet to be examined. In this exploratory study, several of these characteristics, such as exposure to pets when young and as adults and current pet interactions and diet were analyzed from internet survey data. We found that more people identified as dog people (63.3%) versus cat people (36.7%) and preference for dogs remained consistent from childhood to adulthood compared with cats. In individuals who changed species preference, a lack of childhood exposure to cats (47.2%) was significantly associated with the group that changed preferences from dogs to cats from childhood to adulthood, compared with dog ownership as a child in the group that changed preferences from cats to dogs (24.4%). The number of cats and dogs in the home directly correlated with species preference (p < 0.001). Dwelling location was also significantly associated with species preference, with cat people being more likely to live in an urban area and dog people in a rural area (p = 0.002). More time was spent in both active and passive interactions with pets of the preferred species. Cats owned by cat people were more likely to be fed prescription diets compared with cats owned by dog people (p < 0.001). Interestingly, dog people were more likely to feed both their cats (p = 0.012) and dogs (p < 0.001) a raw diet compared with cat people. Additional research is needed to understand the development and impact of owner species preferences on pets to identify risks of suboptimal wellbeing.