Neoplasia is common in pet dogs but accurate figures for the incidence of tumours in this, as in other species, are sparse. The purpose of this study was to document the occurrence of tumours in a defined population of dogs. From a database of 130,684 insured dogs, claims relating to the investigation or treatment of tumours or tumour-like lesions during a 12-month period were accessed and followed up. A total of 2,546 claims were tumour related and were classified according to tumour site and type. Because the demographics of the insured population were skewed towards younger animals, a standard population, as described in the veterinary literature, was used in the calculation of tumour incidence rates. The skin and soft tissues were the most common sites for tumour development, with a standardised incidence rate of 1,437 per 100,000 dogs per year, followed by alimentary (210), mammary (205), urogenital (139), lymphoid (134), endocrine (113) and oropharyngeal (112). Canine cutaneous histiocytoma was the most common single tumour type, with a standardised incidence rate of 337 per 100,000 dogs per year, followed by lipoma (318), adenoma (175), soft tissue sarcoma (142), mast cell tumour (129) and lymphosarcoma (114). These data are unique and provide a valuable basis for future research into the aetiology and epidemiology of canine tumours.

This study was based on a convenience-sampling questionnaire study of pedigree cat breeding in the UK. Data were collated for the births of 1,056 litters from 14 different pedigree breeds and 942 different households. Significant relationships between various outcomes and relevant predictors were assessed by multiple linear regression or logistic regression as appropriate. The overall mean gestation length of 65.1 days varied significantly between the breeds (P<0.0001), and larger litter sizes were associated with shorter gestation lengths (P=0.04). The mean litter size of 4.6 kittens also varied significantly according to breed (P<0.0001). The weight of kittens born alive (overall mean 93.5 g) increased with longer gestation lengths (P=0.0003), decreased with larger litter sizes (P<0.0001) and varied between the breeds (P<0.0001). A total of 8.0% of pregnancies resulted in a caesarean section, with a higher risk associated with smaller litter sizes (P=0.002). Although the frequency of caesarean sections varied from 0 to 18.5% between individual breeds, breed itself was not shown to have a significant independent effect on this likelihood. A mean of 7.2% of all the kittens were stillborn, which varied according to breed (P=0.0003), and the risk of a stillborn kitten increased with litter size (P=0.0001), and with the presence of congenital defects in the litter (P=0.0002). The mean kitten mortality between birth and 8 weeks of age was 9.1%, and the majority of these occurred in the first week of life. Parturition intervals varied widely. The duration of first stage of labour was less than 2h in 82.9% of cats. The interval between the birth of the first and last kitten was less than 6h in 85.7%, but more than 48 h in three cats. A maximum of 48 h was recorded between the births of individual kittens in unassisted deliveries.

Background: Cardiac murmurs associated with valvular regurgitation occur commonly in conditioned performance horses, but their association with athletic performance is unknown.Hypothesis: Cardiac valvular regurgitation has a negative association with race performance. Animals: Five hundred and twenty-six ''race fit'' Thoroughbred racehorses engaged in either flat (race distance 1,000-2,500 m) or jump racing (race distance 3,200-6,400 m).Methods: Cardiac auscultation and color flow Doppler (CFD) echocardiography were performed on 777 occasions. The associations between the presence and severity of either an audible cardiac murmur or valvular regurgitation assessed by CFD, and published, objective measures of race performance were determined using a standard regression approach.Results: The prevalence of murmurs and of regurgitation varied significantly between racetypes (Po.02), generally increasing from 2-year olds to chasers. There were no consistent associations between racing performance and either grade of murmur or regurgitation, whether the presence or absence of regurgitation or murmur, or only murmurs 3/6 or regurgitation 6/9, were considered.Conclusions and Clinical Importance: There were differences in prevalence and severity of murmurs of atrioventricular and aortic valve regurgitation between racehorses in different disciplines. Data also showed that neither regurgitation nor murmurs were negatively associated with Timeform rating, an index of UK racehorse quality, in any of the groups of racehorses studied.

Hypertensive retinopathy was common in cats > or = 10 years of age and was associated with systolic blood pressures > 168 mm Hg when measured by the noninvasive oscillometric technique.

Cardiac morphology in human athletes is known to differ, depending on the sports-specific endurance component of their events, whereas anecdotes abound about superlative athletes with large hearts. As the heart determines stroke volume and maximum O2 uptake in mammals, we undertook a study to test the hypothesis that the morphology of the equine heart would differ between trained horses, depending on race type, and that left ventricular size would be greatest in elite performers. Echocardiography was performed in 482 race-fit Thoroughbreds engaged in either flat (1,000 -2,500 m) or jump racing (3,200 -6,400 m). Body weight and sex-adjusted measures of left ventricular size were largest in horses engaged in jump racing over fixed fences, compared with horses running shorter distances on the flat (range 8 -16%). The observed differences in cardiac morphologies suggest that subtle differences in training and competition result in cardiac adaptations that are appropriate to the endurance component of the horses' event. Derived left ventricular mass was strongly associated with published rating (quality) in horses racing over longer distances in jump races (P Յ 0.001), but less so for horses in flat races. Rather, left ventricular ejection fraction and left ventricular mass combined were positively associated with race rating in older flat racehorses running over sprint (Ͻ1,408 m) and longer distances (Ͼ1,408 m), explaining 25-35% of overall variation in performance, as well as being closely associated with performance in longer races over jumps (23%). These data provide the first direct evidence that cardiac size influences athletic performance in a group of mammalian running athletes. Thoroughbred horses; athletic performance; heart size RESULTS FROM EXTENSIVE RESEARCH into the effects of athletic training and competition on the human heart have demonstrated differing effects of various types of exercise and training (22). Prolonged periods of high cardiac output with minimal change in arterial blood pressure, typical of long-duration endurance training (dynamic exercise), produce increased diastolic load and stimulate compensatory increases in cardiac chamber size (10). In contrast, short-duration "power" training (static exercise), associated with increased cardiac afterload and arterial blood pressure, produces increased left ventricular (LV) wall thickness due to compensatory concentric myocardial remodeling (15). Although sport-specific cardiac adaptations have been studied for many human athletic disciplines with differing static and dynamic exercise components (9, 19), most studies have compared elite human athletes competing in sports at extremes of the power/endurance spectrum. The differences in cardiac adaptation between athletes performing dynamic exercise over different distances, with subtle differences in the power/endurance components of their competitive events, have not yet been fully explored.The role of the heart in defining athletic performance has been the subject of speculation and interest ...