It is well established that small dogs on average have a longer life span than do large dogs; however, the exact mechanisms responsible for this difference are a subject of considerable debate. Using clinical data of over 100,000 individual eye exams from 72 dog breeds of varying size and life span provided by the CERF database, we were able to establish that breed size, life span and the age at which dogs develop non-hereditary, age-related cataracts (ARC) interact. The smallest dog breeds had a lower ARC prevalence between both ages 4 to 5 and for overall life span than medium-sized breeds, which in turn had a lower prevalence than giant breeds. These differences became statistically more significant when comparing small and giant breeds only. Our data also confirmed the inverse relationship between breed size and life span that is generally accepted in the literature. Given that ARC has been shown to be at least partially caused by the accumulation of oxidative damage to the lens, we suggest that it can not only be considered as a general biomarker for life expectancy in the domestic dog, but also for the systemic damages caused by reactive oxygen species (ROS) during the aging process. This suggests that large breeds accumulate more such damage earlier in life than small breeds do, which could be explained by their longer growth period and faster rate of growth, during which the body’s normal anti-oxidative mechanisms may be insufficient. The correlation between ARC incidence, lifespan, and body size suggests new ways of studying the gene expression pathways affecting these attributes, notably those involving insulin-like growth factor 1 (IGF-1). Accumulating more pathological, hormonal and molecular data for dog breeds of different body sizes and rates of growth should also provide new approaches regarding the influence of ROS and the IGF-1 pathway on life span, age-related pathologies and the rate and extent of cell replication that accompanies them.
Inbreeding depression is a widespread and well-documented concern in dog breeding and has been described as a potential animal welfare problem. Consequently, there is currently a considerable movement towards the reduction of inbreeding levels, with the goal of reducing or eliminating inbreeding depression. However, the literature shows that there are mechanisms through which inbreeding depression can be overcome in a population despite continuously high inbreeding coefficients, most notably through purging of the genetic load in relation to genetic bottlenecks, combined with selection for fitness.
Using a pedigree database containing over 50,000 individual Irish wolfhounds dating back to 1862, it could be shown that the breed has gone through at least four genetic bottlenecks since that period, with the result that over 50% of genetic variability in the present population can be explained by just 3 individual ancestors and over 95% by 10 ancestors. However, the exponential increase in population size that took place since about 1965 tends to mask this intense inbreeding when inbreeding is calculated over just a few generations.
When combining the pedigree data with data on individual life span and litter size, no correlation between inbreeding coefficients over 5, 10, 20 and 30 generations as well as calculated back to the beginning of modern breeding and either life expectancy or litter size in Irish wolfhounds could be found. We therefore suggest that the breed may have been subject to purging phenomena during its past genetic bottlenecks.
Our results do not invalidate the well-documented advantages of reducing inbreeding in many breeds; however, they suggest that some breeds may have been subject to purging phenomena and that therefore, caution may be advised in extrapolating results on inbreeding depression between breeds. Research in other breeds with similarly high inbreeding levels (such as the Kromfohrländer) may be useful to further test this hypothesis.
Few tests have been developed to test the cognitive and motor capabilities of domestic cats, in spite of the suitability of cats for specific studies of neuroanatomy, infectious diseases, development, aging, and behavior. The present study evaluated a T-maze apparatus as a sensitive and reliable measure of cognition and motor function of cats. Eighteen purpose-bred, specific-pathogen-free, male, neutered domestic shorthair cats (Felis catus), 1-2 years of age, were trained and tested to a T-maze protocol using food rewards. The test protocol consisted of positional discrimination training (left arm or right arm) to criterion followed by two discrimination reversal tests. The two reversal tests documented the ability of the subjects to respond to a new reward location, and switch arms of the T-maze. Data were collected on side preference, number of correct responses, and latency of responses by the subjects. Aided by a customized computer program (CanCog Technologies), data were recorded electronically as each cat progressed from the start box to the reward arm. The protocol facilitated rapid training to a high and consistent level of performance during the discrimination training. This learning was associated with a decrease in the latency to traverse the maze to a mean of 4.80 ± 0.87 s indicating strong motivation and consistent performance. When the rewarded side was reversed in the test phase, cats required more trials to reach criterion, as expected, but again showed reliable learning. The latency to reward in the first session of reversal increased 86% from the first to the last trial indicating that it may provide a useful index of cognitive processing. Latencies subsequently decreased as the new reversal paradigm was learned. This paradigm provides a relatively rapid and reliable test of cognitive motor performance that can be used in various settings for evaluation of feline cognitive and motor function.
Neuronal ceroid lipofuscinosis is a heritable neurodegenerative disease characterized by accumulation of autofluorescent lysosomal storage granules in neural tissues accompanied by cognitive decline, seizures, and locomotor deficits. Our laboratory identified a mutation, occurring in Dachshunds, of tripeptidyl peptidase I (TPP1), the canine ortholog of human CLN2 (Awano et al., 2006). In order to establish biomarkers for evaluating experimental therapies in this model, we characterized phenotypic changes in seven age-matched dogs over an 8 month period.
Genotyping indicated that 2 puppies were homozygous for the mutant allele and 5 were homozygous normal. All dogs had regular physical and neurologic examinations. Funduscopy, electroretinography and cognitive function testing were performed at regular intervals. Cognitive function was assessed with the CanCog T-maze apparatus.
Physical examination remained normal for all dogs. In affected dogs, changes in funduscopy, ERG and pupillary light reflexes presented between 5.5 and 6 months of age. By 7 months, mild intention tremor and cerebellar ataxia were observed. Affected dogs were still visual at 8 months. MRI revealed diffuse cerebral and cerebellar atrophy and brain weights were reduced by 15% when compared to normal dogs of similar size.
There were pronounced differences in performance between affected and normal dogs in the T-maze learning task. A cognitive deficit in the affected dogs was clearly present at 4 months of age and progressively worsened at each subsequent time point. We conclude that the reversal learning task is a sensitive, early measure of disease progression which could serve as a useful biomarker for evaluation of treatment strategies.
In 1999, 8 of 27 (29.6%) US veterinary schools had a full-time behaviorist. A survey was conducted in the summer of 2007 to obtain information about the availability of behavioral medicine educational opportunities in colleges of veterinary medicine in North America. Twelve of 32 (37.5%) veterinary colleges have a veterinary behaviorist on staff, and 9 (28.13%) support residency programs. Fourteen (43.75%) have a normal animal behavior course, 12 (37.5%) an abnormal/clinical behavior course. Nine universities (28.13%) have a combined normal/abnormal animal behavior course in lieu of separate normal and abnormal behavior courses. Seven have officially recognized student chapters of the American Veterinary Society of Animal Behavior. Four have no behavioral medicine presence in the form of faculty, behavior courses, interested staff, or a student club. Inclusion of behavioral medicine into the curricula of North American colleges of veterinary medicine has been slow in the 14 years since the recognition of the specialty by the AVMA's American Board of Veterinary Specialties. Each year, behavior problems account for a large number of deaths, by euthanasia, of otherwise healthy pets. Increasing opportunities in behavioral medicine at the university level would have a considerable trickle-down effect by affecting the perception by owners and the comfort level of practitioners in identifying, managing and treating behavior problems in pets.
Feline idiopathic cystitis (FIC), is the most common medical cause of elimination change in the cat, and hence is an important differential when working up cats presenting with inappropriate elimination. A recent case-control study found that case cats were more likely than the control population to be male, overweight, and pedigreed, but the study also found that several stress factors were “flare factors” associated with the onset of a bout of clinical signs. A 5-year-old male, neutered, domestic shorthaired cat presented with recurrent bouts of dysuria and hematuria. A full medical work up eliminated other causes, leading to the diagnosis of FIC. On behavioral assessment, the cat was found to be one of 6 within the household. He showed no signs of regarding any of the other cats as part of his social group. A program of behavior therapy was instituted, which involved ensuring the patient had a separate “core area” and easy access to important resources. In addition, visual access to cats from outside the household was restricted. The cat was followed up for a period of 7 months. There was no further recurrence of clinical signs for 6 months, after which clinical signs returned. Further investigation revealed that this outbreak occurred 2 days after the owner confined the cats in close proximity again. This case provides an interesting example of how bouts of clinical signs in FIC cats can often be linked to specific “stressful” events, and how such outbreaks can be reduced or prevented through the implementation of a specific program of behavior therapy.
It is possible to modify lifting techniques in small laboratory pigs to evoke less of a fear response, strengthen the human–animal bond, and improve welfare. The authors hypothesized that recently weaned pigs lifted with a ventral (belly) scoop method would show less fear of new humans and less fear during treatment than pigs lifted vertically by their hind limbs. To evaluate this hypothesis, 32 Yorkshire-cross pigs (age 3 weeks) were divided into 8 groups of 4. All pigs were acclimated to humans for 11 days and uniformly enriched prior to any lifting tests. Pigs were randomly assigned to 1 of 4 different combinations of ventral and/or vertical lifting techniques that varied by consecutive day (1 ventral-ventral; 2 ventral-vertical; 3 vertical-ventral; 4 vertical-vertical). Each day, data were collected regarding pigs’ aversion to lifting and willingness to be caught multiple times. Two hours later, their time to approach a new person and proportion of time spent hiding from the new person were also measured. Aversion scores were assigned based on duration of squealing, shaking, and freezing responses during lifting. Pigs that were lifted using alternate methods on consecutive days showed significantly less aversion when being scooped ventrally (P = 0.008) as compared to lifted vertically by their hind limbs. Additionally, behavioral trends were identified during the study. Based on standardized aversion scores, this research shows that the ventral scoop method induces less fear than the vertical lift method.
Currently in the United Kingdom, there is no legal requirement for anyone giving advice on the training of animals or the treatment of behavioral disorders to hold a formally recognized qualification. The first professional organization in this field in the United Kingdom, the Association of Pet Behaviour Counsellors (APBC), was founded in 1989 with the avowed aim of promoting and developing the profession of pet behavior counseling and standardizing the service provided. Essentially a trade association to advance the interests of its members, APBC members work on veterinary referral only and are required to adhere to a code of practice. Through the activities of veterinary surgeons with a specialist interest in behavioral medicine, there have been moves to better recognize those with competencies in this area in the United Kingdom and Europe. The use by veterinarians and large animal charities of appropriate recognized specialists with accredited skills from nationally recognized bodies in the treatment of behavioral disorders-be they veterinary behaviorists or paraprofessional clinical animal behaviorists-would seem to fulfill this requirement in a way that the existing practice of using practitioners with no formally recognized qualifications or verified skills does not, and should lead to a shift and improvement in current standards of practice. If it does not, then case law will determine the extent to which such disregard is a neglect of this duty of care. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Romanov ewes give birth to an average of 2.8 lambs per partum and display maternal ability over other sheep breeds; however, few studies have investigated their mother–young mutual recognition. Here, 8 primiparous and 7 maternally experienced (multiparous) ewes and their lambs were studied. Maternal selectivity was evaluated at 3 hours postpartum during two consecutive periods of 3 minutes each. Ewes were tested with their own lambs and then with alien lambs. High- and low-pitched bleats, attempts and rejection to the udder, aggressive behavior toward the lambs, and amount of time that the mother permits the lamb to be near the udder were recorded.
At 8 hours postpartum, a double-choice test was performed to assess distal recognition of the lamb by the mother; in the lambs, a double-choice test was performed at 24 hours of age. Latency to reach one of the animals, frequency to visit each, time spent near the choice subject, time spent looking toward them, and frequency of vocalization were recorded. A Mann–Whitney U-test was used for between-group comparisons, and a Wilcoxon test was used for within-group comparisons.
At 3 hours postpartum, most of the ewes (multiparous and primiparous) were selective; however, multiparous ewes tended to have a higher index of acceptance of their own lambs than primiparous ewes (2.74 ± 0.66 vs 0.56 ± 0.76, P = 0.083).
At 8 hours postpartum, multiparous ewes spent more time looking toward their own lambs than primiparous ewes (50 ± 11.8 vs. 15.8 ± 8.9 s, P = 0.018). Compared to primiparous ewes, multiparous ewes spent more time near their own lambs than near alien lambs (84.85 ± 19.6 vs. 21.7 ± 9.7 s, P = 0.05), and more time looking toward their own lambs than toward alien lambs (P = 0.018).
At 24 hours after birth, lambs born to multiparous ewes spent more time near their own mothers than near alien mothers (P = 0.043) and visited their own mothers more than they visited alien mothers (P = 0.05). In contrast, lambs born to primiparous ewes did not show similar behaviors (P ≥ 0.73). In conclusion, in Romanov sheep, maternal experience affects mostly non olfactory recognition of the lamb and also influences the ability of the lamb to recognize its mother.
An improved understanding of the early behavioral indicators of lumbosacral disease in working dogs may allow earlier interventions and help reduce premature retirement because of disability. However, recognition of early behavioral indicators can be challenging in stoic, high-drive working dogs because they often mask clinical signs. The purpose of this feasibility study was to develop a technique for visualizing canine skeletal movements during working tasks and to describe veterinary clinical specialist opinions on the utility of the visualization technique. Three detection-trained police dogs with a recent history of working task deficits and suspected lumbosacral disease were recruited for the study. Conventional and motion capture video recordings were acquired as dogs performed walking and search high working tasks. Whole-body computed tomography (CT) scans were acquired using clinical multislice CT scanners. Image data from motion capture recordings and whole-body CT scans were analyzed and merged. Three-dimensional (3D) computer animation video clips of skeletal movements were created for each dog and each task, using multiple viewing angle perspectives. Interactive meetings with veterinary clinical specialist reviewers were used to refine point placements for the final renderings. Veterinary clinical specialists reviewed final 3D animation movie clips and recorded their opinions on the utility for the visualization technique. Veterinary clinical specialists reported that the computer animations helped them recognize behavioral characteristics that they had not initially noticed in physical examinations. Potential applications for this visualization technique include creating educational training aids for veterinary students, owners, and handlers; assisting veterinarians in planning rehabilitative treatments; and assisting researchers in developing computer models for biomechanical analyses. Future controlled prospective studies are needed in a large number of normal and affected working dogs to improve accuracy of the visualization technique and test the effect of the technique on observer performance.