Reduction in the incidence of elbow dysplasia in four breeds of dog as measured by the New Zealand Veterinary Association scoring scheme

Animal medical genetics: a historical perspective on more than 50 years of research into genetic disorders of animals at Massey University

Over the last 50 years, there have been major advances in knowledge and technology regarding genetic diseases, and the subsequent ability to control them in a cost-effective manner. This review traces these advances through research into genetic diseases of animals at Massey University (Palmerston North, NZ), and briefly discusses the disorders investigated during that time, with additional detail for disorders of major importance such as bovine α-mannosidosis, ovine ceroid-lipofuscinosis, canine mucopolysaccharidosis IIIA and feline hyperchylomicronaemia. The overall research has made a significant contribution to veterinary medicine, has provided new biological knowledge and advanced our understanding of similar disorders in human patients, including testing various specific therapies prior to human clinical trials.

Analysis of risk factors for elbow dysplasia in giant breed dogs

Objective: Identify radiographic risk factors for development of elbow dysplasia in giant breed dogs less than one year of age.

Methods: Twenty-five giant breed puppies (Bernese Mountain dogs, English Mastiff, and Newfoundland) were studied. Both elbows of each dog were radiographed monthly from two to six months of age, then every other month until radial and ulnar physeal closure, followed two months later by bilateral elbow computed tomography. Radiographic parameters measured included the presence or absence of a separate centre of ossification of the anconeal process (SCOAP), medial coronoid disease (MCD), ununited anconeal process, humeral osteochondrosis, elbow incongruity, as well as the length of the radius and ulna, radius-to-ulna ratio, and date of closure of the radial and ulnar physes.

Results: Fifteen dogs completed the study. Two Bernese Mountain dogs were diagnosed with MCD. Risk factors significantly associated with medial coronoid disease included dyssynchronous physeal closure and a decreased radius-to-ulna ratio, both detected between eight to 11 months of age. A separate centre of ossification of the anconeal process was present in 60% of the dogs, and was not a risk factor for development of elbow dysplasia.

Clinical significance: Transient, dyssynchronous growth of the radius and ulna may be a risk factor for development of MCD in Bernese Mountain dogs. Dyssynchronous physeal closure or decreased radius-to-ulna ratio prior to radiographic closure of the distal ulnar and radial physes warrants further study in Bernese Mountain dogs and other breeds subject to MCD development.

Age, breed, sex distribution and nutrition of a population of working farm dogs in New Zealand: results of a cross-sectional study of members of the New Zealand Sheep Dog Trial Association

AIM

To establish baseline information about age, breed, sex distribution and feeding practices for a population of working farm dogs owned by members of the New Zealand Sheep Dog Trial Association (NZSDTA) throughout New Zealand.

METHODS

Questionnaires were sent to members of the NZSDTA in August 2007, requesting information on the size and terrain of the farms where they worked, as well as the breed, weight, age and sex of each working dog they owned, feeding regime employed, diet fed, work levels, and general health of their dogs.

RESULTS

The survey was completed by 542/676 (81%) of the eligible sample population, and provided information on 2,861 dogs, excluding those <1 year old. All of the dog owners surveyed worked on sheep and beef-cattle farms. The median farm size was 440 [Inter-quartile range (IQR) 132-1,200] ha and varied with region. The majority of farms were situated on either hill country (184/542; 34%) or a mixture of hilly and flat terrain (260/542; 48%), and had a median of six (IQR 5-8) working dogs per farm. The median age of dogs was 3.0 (IQR 2.0-6.0) years. Heading dogs were the most common type of working dog (1,510/2,861; 52.8%), followed by Huntaways (1,161/2,861; 40.6%). The gender distribution of all dogs was biased towards males (57%), but this decreased with age. There was a positive association between the number of dogs on a farm and perceived level of tiredness of dogs (p<0.001), but there were no differences in levels of tiredness between farms of different terrain. Most owners (526/542; 97%) fed their dogs once a day. The most common diet fed was a combination of dry food and homekill, which was fed by 328/542 (61%) owners during peak and 313/542 (58%) during off-peak periods of work.

CONCLUSIONS AND CLINICAL RELEVANCE

This study has established baseline information on the age, breed, gender and nutrition of a large population of working farm dogs in New Zealand. Current feeding practices employed by owners include offering a substantial amount of homekill to their animals. Homekill may be deficient or marginal in vitamins and minerals, therefore opportunities could exist to improve the diets and therefore the longevity and performance of these dogs.