The effects of the stress of long-term physical and psychological training on the red blood cell picture in dogs

The effect of the physical and psychical load of long-continued training on the components of the red blood picture was studied in thirty clinically healthy dogs of two age categories. The values of erythrocytes were found to be increased whereas those of haemoglobin, haematocrit and other components (MCV, MCH, BI, MCHC) were depressed. The effects are discussed of training, adaptation process, parasympathicotonic form of overload, and qualitative nutrition deficiency as a reflection of the studied training load as exerted on certain insufficiency of the desired formation of the red blood picture, and thereby of a possible adverse impact on the performance of the trained dog.     

Effect of dorsal hip loading,sedation, and general anesthesia on the dorsolateral subluxation score in dogs

OBJECTIVE: To determine whether dorsal loading of the pelvis and type of chemical restraint affected the dorsolateral subluxation (DLS) score of dog hips. STYDY DESIGN: In vivo testing of diagnostic method. ANIMALS: Labrador retrievers, Greyhounds, and crosses between both breeds (n = 119 dogs). METHODS: Dorsal load was applied to the hips through a strap that was placed over the hips, and the peak vertical and steady-state vertical, ground-reaction forces exerted on the stifles were measured in the DLS position. The DLS score was measured with their hips under dorsal load and compared with the DLS score without load. For 24 dogs, the DLS score was measured both under chemical restraint (medetomidine) and under general anesthesia. Wilcoxon-signed rank test and paired t test was used to compare effects of dorsal load and restraint method on the left and right DLS hip score, and P <.05 was considered significant. RESULTS: Both stifles together accepted median 15% body weight in the vertical plane in the unloaded steady state. Loading the hips increased the steady-state, vertical ground-reaction force to 34% body weight. At 8 months of age, loading significantly decreased the DLS score from 65% +/- 11% (mean +/- SD) to 60% +/- 12% for left hips and 66% +/- 11% to 63% +/- 13% for right hips. The left hip DLS score was affected by load more consistently than the right hip. In general, loading the hips decreased the DLS score in all breeds by 4% to 6% except for the greyhounds, in which the DLS score was unchanged by dorsal loading. When grouped by their DLS scores, load significantly decreased DLS scores in dogs with unloaded scores greater than 55% (nondysplastic), whereas DLS scores of dogs with unloaded scores between 55% and 45% (dysplastic) and less than 45% did not change significantly with load. Unloaded scores did not change significantly when compared under sedation versus general anesthesia. However, load significantly decreased the DLS score under general anesthesia for the left hip but not for the right hip. CONCLUSIONS: Less than half of the vertical ground-reaction force normally exerted by the hindlegs of a standing dog was sufficient to induce hip subluxation in the DLS position. Although dorsal loading approximately doubled the steady-state, vertical ground-reaction force, the decrease in the DLS score under load was never greater than 6%. Furthermore, the DLS scores of dogs most likely to be dysplastic (based on DLS scores <45%) were not affected by load, whereas load slightly decreased DLS cores of dogs with DLS scores greater than 55%. CLINICAL RELEVANCE: External influences can change the DLS score significantly, but the magnitude of change is unlikely to be of clinical importance, making the method useful as a field screening test for both dysplastic and nondysplastic hips in young dogs.     

The effect of training stress on enzyme activity in working dogs

The activities were studied in five kinds of enzymes (aspartate aminotransferase - AST, alanine aminotransferase - ALT, lactate dehydrogenase - LD, the thermally stable fraction of lactate dehydrogenase - LD-1, and alkaline phosphatase - ALP) of 30 male dogs. The dogs, divided into two age categories, were studied during a long-continued training (130 days). Both transaminases exhibit characteristic changes in the activity, with a depression at the beginning between the 30th and 40th days of training, followed by a slow increase in AST and by a rapid increase in ALT, continuing until the end of the training period. A statistically significant activity pattern was recorded in LD: the activity declined continuously in both age groups of dogs. LD-1 exhibited an activity depression continuing until the 70th day of training, followed by an increase which reached statistical significance towards the end of the training. ALP activity varied regularly, but always remained significantly below the starting values. The enzymatic activities can be used as partial tests during the scientific management of the training of dogs in relation to the physiological and pathophysiological processes in the bodies of the dogs subjected to the training stress.     

Analysis of feline,canine and equine hemograms using the QBC VetAutoread

Blood samples form 120 consecutive clinical cases (40 cats, 40 dogs and 40 horses) were analyzed on the QBC VetAutoread analyzer and the results compared with those obtained by a Baker 9000 electronic resistance cell counter and a 100-cell manual differential leukocyte (WBC) count. Packed cell volume (PCV), hemoglobin (Hb) concentration, mean cell hemoglobin concentration (MCHC), and platelet, total WBC, granulocytes, and lymphocyte plus monocyte (L+M) counts were determined. Indistinct separation of red blood cell and granulocytes layers on the QBC VetAutoread was observed in samples from five cats (12.5%), two dogs (5%), and one horse. Significantly different (P=0.002) median values for the two methods were obtained for PCV, Hb concentration, MCHC and platelet count in cats; PCV, MCHC, WBC, count and granulocytes count in dogs; and PCV, Hb concentration, MCHC and WBC, granulocytes and platelet counts in horses. Results from the QBC VetAutoread should not be interpreted using reference ranges established using other equipment. Results were abnormal on a limited number of samples; however, when correlation coefficients were low, marked discrepancy existed between values within as well as outside of reference ranges. Spearman rank correlation coefficients were excellent (r=0.93) for PCV and Hb concentration in dogs, and Hb concentration and WBC count in horses. Correlation was good (r=0.80-0.92) for PCV and Hb concentration in cats, WBC count in dogs, and PCV, granulocytes count and platelet count in horses. For remaining parameters, correlation was fair to poor (r=0.79). Acceptable correlations (r>0.80) were achieved between the two test systems for all equine values except MCHC and L+M count, but only for PCV and HB concentration in feline and canine blood samples.     

Prediction of future development of canine atopic dermatitis based on examination of clinical history

OBJECTIVES: The aim of this study was to identify clinical features that could be used to identify individual dogs within the Guide Dogs for the Blind Association canine population at risk of being diagnosed as atopic in the future before they had fully developed the condition. METHODS: Clinical histories of atopic and non-atopic dogs from the Guide Dogs for the Blind Association population were analysed and statistically significant differences identified between the two groups. RESULTS: Atopic dogs were consistently affected by skin disease at a younger age than non-atopic dogs and that there was a significant difference in event curves between atopic and non-atopic dogs at 10 months of age. From a predictive point of view, dogs that suffered from four or more episodes of atopic-type skin disease by the age of 15 months were at an increased risk of developing atopic dermatitis. CLINICAL SIGNIFICANCE: It is suggested that the clinical history of all dogs from the Guide Dogs for the Blind Association about to undergo training should be examined for these factors to assess whether or not they should undergo training.     

Mineral metabolism in dogs during training and work stress

The contents of basic mineral elements (Na, K, Mg, Ca, P, Cl) were investigated in service dogs during their long-term basic training; the dogs belonged to two age categories, and the influence of different work stress (sentry, tracker, watch dogs) on the changes in the contents of these elements was also studied. Great changes in the dynamics of individual elements were demonstrated during the long-term training, signalling the beginning of muscular insufficiency and fatigue in the course of training, as well as the onset of adaptation processes to the psychic and physical stress (Na, K, Mg). The increased contents of Ca and P at the beginning and during the intensive training with a risk of bone demineralization, indicate the beginning of osteopathy, disorders of muscular and nervous irritability and unbalanced feed rations. The satisfactory adaptation process with the stabilized internal environment in the sphere of minerals metabolism is documented in service dogs by the long-term and qualitatively different work stress. The results of our studies can be included into the tests of training and work stress in service dogs.     

Age-related alterations to immune parameters in Labrador retriever dogs

In order to assess age-related changes in the immune status of Labrador retriever dogs, leukocyte phenotypes, lymphocyte proliferative capacity, and serum antibody levels were measured in four cohorts of dogs, ranging from 2 to 10 years of age. Absolute numbers of white blood cells, lymphocytes, monocytes, granulocytes, and CD3+, CD4+, CD8+ and CD21+ lymphocytes significantly decreased with increasing age. Relative percentages of lymphocytes and CD4 cells were significantly decreased, and relative percentages of granulocytes and CD8 cells significantly increased, with age. The CD4:CD8 ratio showed a significant age-related decrease. Proliferative responses of T-cells to mitogens in whole-blood cultures either increased (Concanavalin A) or remained the same (phytohemagglutinin) with age when data was normalised to allow for differences in responding cell number. Similarly, normalised data of proliferative response to anti-CD3 stimulation together with phorbol 12-myristate 13-acetate showed an age-related increase. Serum levels of total IgA significantly increased with age whereas total IgG levels remained unchanged. These observations illustrate a significant change to a number of immune parameters with age. However, further work is required to determine whether the differences reported here are sufficient to cause overt or functional immune senescence in Labrador retriever dogs.     

Prevalence and risk factors of behavioural changes associated with age-related cognitive impairment in geriatric dogs

O bjectives : The aim of this study was to describe the prevalence and severity of behavioural changes associated with age and their relationship to risk factors such as sex, reproductive status, bodyweight and age.
M ethods : A cross-sectional study design was chosen. A total of 325 geriatric dogs were included. Owners of dogs older than nine years were interviewed by a veterinary behaviourist. Structured phone interviews were used to gather information about four behavioural categories related to cognitive impairment: sleep/wake cycles, social interaction, learning and house training and signs of disorientation.
R esults : Signs of cognitive impairment showed a prevalence of 22·5 per cent in geriatric dogs. Sex and age emerged as significant predictor variables. Females and neutered dogs were significantly more affected than males and entire dogs, respectively. Prevalence and severity increased with age. Although weight was not a statistically significant predictor variable, smaller animals had greater odds of showing age-related cognitive impairment. The most impaired behavioural categories were social interaction and house training.
C linical S ignificance : Age-related behavioural changes should be considered by practicing veterinarians because of their relative high prevalence among geriatric dogs, especially in females.     

Evidence for a relationship between Leishmania load and clinical manifestations

Visceral leishmaniasis (VL) is a life-threatening disease of medical, social and economic importance in endemic areas. Dogs are the main reservoir of Leishmaniainfantum. In this study, the authors investigated a group of 56 natural infected dogs to establish the relationship between parasite load and various clinical forms of leishmaniasis.The sick dogs were monitored at the beginning from clinical and physiological point of view. Leishmania load was measured by real-time PCR assay on whole blood samples and lymph node aspirates, collected at the time of diagnosis.Our results indicate that a higher quantity of Leishmania DNA was found in the lymph nodes of dogs characterized by maximum clinical score. This interesting finding indicates the presence of a positive relationship between Leishmania load and clinical manifestations in dogs showing a severe clinical form of leishmaniasis.     

Behavior of hearing or vision impaired and normal hearing and vision dogs (Canis lupis familiaris): Not the same,but not that different

The article compared behavioral characteristics of dogs (Canis lupis familiaris) labeled as hearing and/or vision impaired by their owners with cohort dogs labeled as having normal hearing and vision (NHV) by their owners. The Canine Behavioral Assessment and Research Questionnaire, developed by Hsu and Serpell (2003), was used to survey owners. Four hundred sixty-one dog owners completed the online survey, with 183 of these being owners of hearing and/or vision impaired (HVI) dogs. Data analysis revealed that HVI dogs were reported by owners to show less aggression, less excitement, and were less likely to engage in behaviors, such as chasing of rabbits and rolling in feces than their normally hearing/seeing (NHV) cohorts. HVI dogs, however, were reported to be more likely to chew inappropriate objects, consume feces, bark excessively, and engage in greater licking behavior. When owners were surveyed about the type of training method used, owners of HVI dogs were found to be more likely to use hand signs, physical prompts, or combination of these training methods. Owners of NHV dogs reported being more likely than owners of HVI dogs to use gestures or report no formal training with their dogs. The data provide evidence that HVI dogs are as trainable as NHV dogs, can make excellent pets, and show behavior that is well within the parameters of NHV dog behavior. Still, because of their sensory limitations, specialized training methods and adaptations should be implemented with these dogs. This may limit HVI dogs to owners who are motivated, understand the sensory deficits, and are willing to engage in the modified training.     

A standardized behavior test for potential guide dog puppies: Methods and association with subsequent success in guide dog training

An early understanding of behavioral suitability for guiding work in domestic dogs (Canis familiaris) would be useful for organizations which train dogs as mobility aids, such as the Guide Dogs for the Blind Association. We explored the potential for a standardized test of behavior in young dogs to reflect subsequent success in guide dog training. Five hundred eighty-seven potential guide dogs were exposed to a series of eight stimuli at 6-8 weeks of age. The responses of dogs were scored on a 7-point scale according to either responsiveness to human assessor or to environmental stimuli, on stimuli comprising following when called; retrieve; gentle restraint; noise; stroking; a moving toy squirrel; encouragement to go through a tunnel; and encouragement to go over a ramp. Five of these stimuli showed some association with success in guide dog training, and three of these stimuli could be usefully combined in a logistic regression model of success in training. There is potential for this test to be used to predict suitability for guiding work but adjustments to the scoring protocol are recommended.     

Histopathological changes in canine allergic contact dermatitis patch test reactions. A study on spontaneously hypersensitive dogs

The histopathology of allergic patch test reactions in dogs with spontaneous allergic contact dermatitis (ACD) was investigated. Epidermal necrosis was present in half of the biopsies and neutrophilic granulocytes were present within epidermis in these biopsies as well as in some of the biopsies without necrosis. Spongiosis was only occasionally observed. Dermal infiltration with neutrophilic granulocytes and oedema was found in all biopsies while the number of lymphocytes was small. The results may indicate a different secretion of or responsiveness towards cytokines in canine ACD compared to ACD in man where epidermal necrosis is not a characteristic feature and where the predominant inflammatory cell is the lymphocyte. It is anticipated that histopathological investigation of patch test reactions in dogs will not be helpful in discriminating between allergic and toxic patch test reactions.     

Onset and duration of immunity against Babesia canis infection in dogs vaccinated with antigens from culture supernatants

It has previously been shown that dogs can be vaccinated against heterologous Babesia canis infection using a vaccine containing soluble parasite antigens (SPA) from in vitro cultures of B. canis and B. rossi that are adjuvanted with saponin. In the present study the onset and duration of immunity of vaccinated dogs were studied. Results showed that 3-26 weeks after initial vaccination, dogs effectively limit the level of SPA in plasma upon challenge infection, which was reflected in limited duration and extent of clinical manifestations. There was no statistically significant effect of vaccination on the parasite load in the circulation, which was determined from blood smears. It was further shown that the level of immunity of primary vaccinated dogs (priming and booster vaccination with a 6-week interval) and that of repeatedly vaccinated dogs (a single additional vaccination 6 months after primary vaccination) is comparable. From this study it is concluded that vaccination with this preparation induces protective immunity against clinical babesiosis from 3 weeks after booster vaccination onwards, and remains effective for a period of at least another 6 months. A single booster vaccination is sufficient to maintain immunity for at least another 6 months.     

Collie eye anomaly in the rough collie in Norway

The results of eye examinations of 741 rough collies for collie eye anomaly (CEA) are described. Of the examined dogs, 40-8 per cent had CEA, including, in most cases, chorioretinal dysplasia (CRD). 7-7 per cent had coloboma of the optic disc while 3–5 per cent had complications of CEA, either retinal detachment or intraocular bleeding. There was no sex difference nor was the frequency of the disease influenced by coat colour. After estimating the total frequencies of the different manifestations of the disease, the dogs were divided into two groups according to the age at first examination. In the group of dogs examined between seven weeks and three months old, 48-9 per cent had CEA, compared to a frequency of 25-6 per cent in the group of dogs examined after three months of age. All the puppies with coloboma also showed signs of CRD, while among the older dogs 11 of the 66 CEA cases reported showed signs of coloboma without CRD. Twenty-two dogs which had been examined as puppies and given the diagnosis CEA with minor chorioretinal changes were re-examined at an older age. Of these dogs, 15 had ophthalmoscopi-cally normal fundi at re-examination while seven were unchanged from the first examination.     

Ocular manifestations of natural canine monocytic ehrlichiosis (Ehrlichia canis): a retrospective study of 90 cases

OBJECTIVE: To investigate the spectrum, prevalence and treatment response rate of ocular manifestations associated with natural canine monocytic ehrlichiosis (CME) due to Ehrlichia canis. METHODS: The medical records of 90 dogs that were admitted for primary ocular problems and reacted positive for E. canis serum antibodies were reviewed. All the dogs were treated with oral doxycycline. In 79 dogs, a combination of systemic corticosteroids and/or topical anti-inflammatory, mydriatics/cycloplegics and antibacterial agents were applied. RESULTS: The dogs ranged from 0.5 to 15 years in age; 55 were male and 35 female. A total of 19 breeds were represented. In the majority of dogs, ocular abnormalities were noticed in conjunction with other CME-induced clinical signs. In 30/90 dogs, ophthalmic signs were the sole presenting complaint. Unilateral (22/90, 24.5%) and bilateral (68/90, 75.5%) uveitis was the most common ophthalmic diagnosis and was classified as anterior, posterior or panuveitis in 58 (64.5%), 8 (8.9%) and 24 (26.6%) of the dogs, respectively. Bilateral uveitis was significantly more common than unilateral uveitis (P < 0.0001), and anterior significantly more common than posterior uveitis (P < 0.0001) or panuveitis (P < 0.0001). In addition, corneal ulceration (12/90, 13.3%), necrotic scleritis (10/90, 11.1%), low tear production (8/90, 8.9%) and orbital cellulitis (3/90, 3.3%) were seen. Of the 45 (50%) dogs with a satisfactory follow-up, 25 (55.5%), 11 (24.5%), and 9 (20%) showed complete, partial and poor response to treatment, respectively. The number of dogs exhibiting complete resolution of the ocular manifestations was significantly higher than those with partial (P < 0.0001) or poor (P < 0.0001) response. CONCLUSIONS: CME should be considered a major differential for a wide range of ocular manifestations exhibited by dogs residing in the endemic areas of the disease. Anterior bilateral uveitis appears to be the most prevalent ocular lesion and a favorable outcome to systemic and topical treatment may be expected in the majority of the affected dogs.     

Experimental transmission of a granulocytic form of the tribe Ehrlichieae by Dermacentor variabilis and Amblyomma americanum to dogs

Transstadial transmission of granulocytic Ehrlichieae in dogs was attempted using ticks, Amblyomma americanum and Dermacentor variabilis. Ticks were exposed by feeding as nymphs on acutely infected pups; adult ticks then fed to repletion on susceptible adult dogs that were monitored daily for signs of infection. Evidence of transmission was not observed in control dogs or in those exposed to D variabilis. In contrast, dogs exposed to A americanum developed serologic or clinical evidence of infection, but organisms were not seen in blood smears until corticosteroids were administered, causing recrudescence and accompanying parasitemia. At 12 days after subinoculation of blood obtained from donor adult dogs, before corticosteroids were administered, a febrile response, thrombocytopenia, and appearance of morulae in neutrophilic granulocytes were observed in 2 susceptible recipient dogs.     

Isolation of granulocytes and mononuclear cells from the blood of dogs, cats, horses and cattle

A simple discontinuous Percoll density-gradient technique was adapted for isolation of granulocytes and mononuclear cells from cats, dogs, horses and cattle. Separation was accomplished at low speeds using a standard tabletop centrifuge. Cell purity was 100% for both granulocytes and mononuclear cells and cell viability exceeded 95%. Percent recovery of leukocytes ranged from 69 to 83%.     

Factors associated with success in guide dog training

Tests of motor laterality and behavioral reactivity, as well as salivary cortisol concentrations, were examined in this pilot study to identify dogs best suited to guide dog work. Over a 14-month period, lateralization tests were conducted and cortisol concentrations were determined on 3 separate occasions, and temperament testing was performed on 2. Potential guide dogs (N = 43) involved in this study were 5 golden retrievers (4 males, 1 female) and thirty-eight Labrador retrievers (8 black males, fifteen yellow males, 5 black females, and ten yellow females). Results from these tests were then compared with the ultimate success of the dogs in the Guide Dogs NSW/ACT training program. This comparison produced evidence that motor lateralization (particularly the rate at which both paws were used during the Kong Test and the lateralization index during the Tape Test), reactions to an unfamiliar dog, the latency for dogs to drop and rest during an uninterrupted period, and the dog's color and breed were predictive of ultimate success. This study also identified 14 months of age as a more accurate time to assess dogs for these traits than either 6 months of age or at the age at which they completed their training (ranging from 14 to 20 months of age).     

Impact of individual training parameters and manner of taking breath odor samples on the reliability of canines as cancer screeners

The aim of this study was to assess the progress in operant conditioning of dogs during 3 training phases up to a level where the dogs performed a minimum of 40 correct indications without false alerts and hesitations in at least 100 trials in each phase, and to compare the training results with the working phase. Breath samples from 57, 45, and 118 patients with breast cancer, melanoma, and lung cancer, respectively, were used as patterns, with samples from 305 healthy volunteers as controls. Six dogs in 2 age-groups (20 months vs. 6 months old) were used for the training. In phase I, the dogs were trained to indicate by sitting or lying down before the breath samples taken from cancer patients (pattern odor) coupled with food odor and placed among 4 blank samples (a lineup of 5 samples). In phase II, a pattern sample without food odor was placed among blank samples. In phase III as well as in the working phase, a pattern sample was placed among control samples. Significant individual differences were found in dogs’ performance during the training. The percentage of trials with prompts to achieve self-dependent work decreased in older dogs in consecutive training phases, but increased in phase II in the younger dogs. The increasing level of challenge in consecutive training phases resulted in a higher percentage of false alerts and misses, and in younger dogs, decreased motivation for sniffing the odor samples was observed in training phase III. Nonsignificant and negative correlations between the training phases and working phase in the percentage of correct indications and false alerts show that it is difficult to predict the performance of fully trained dogs on the basis of the results achieved during the training. Fully trained dogs discriminated pattern breath samples (cancer) from healthy controls with 79% sensitivity and 78% specificity, or with 50% sensitivity at the probability of correct response by chance of 50% and 20%, respectively. The sensitivity decreased to 68% and 37%, respectively, when each sample was tested only once, although being better than by chance (P < 0.05). The percentage of false alerts and misses is difficult to reduce during the training; thus, the percentage of correct indications tended to decrease in the course of training phases II and III. Odor samples taken in hospitals may contain components of “hospital odors,” which may be a confounding factor for dogs’ indications. Using trained dogs for cancer screening on the basis of detection of odor markers still requires further study.     

Medical and behavioral surveillance of dogs deployed to the World Trade Center and the Pentagon from October 2001 to June 2002

OBJECTIVE: To evaluate early medical and behavioral effects of deployment to the World Trade Center, Fresh Kills Landfill, or the Pentagon on responding search-and-rescue (SAR) dogs. DESIGN: Prospective double cohort study. ANIMALS: The first cohort included SAR dogs responding to the September 11, 2001, terrorist attacks (deployed), and the second cohort included SAR dogs trained in a similar manner but not deployed (controls). Enrollment occurred from October 2001 to June 2002. PROCEDURE: Dogs were examined by their local veterinarians; thoracic radiographs and blood samples were shipped to the University of Pennsylvania for analysis. Handlers completed medical and training histories and a canine behavioral survey. RESULTS: Deployed dogs were older and had more search experience than control dogs. Serum concentrations of globulin and bilirubin and activity of alkaline phosphatase were significantly higher in deployed dogs, independent of age and training. Despite significant differences in several blood parameters, values for both groups were within reference ranges. No pulmonary abnormalities were detected on radiographs, and no significant differences in behavior or medical history were detected between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Within the first year following the September 11 attacks, there was no evidence that responding dogs developed adverse effects related to their work. Mild but significantly higher serum concentrations of globulin and bilirubin and activity of alkaline phosphatase in deployed dogs suggested higher antigen or toxin exposure. These dogs will be monitored for delayed effects for at least 3 years.