Factors associated with past and potential future use of veterinarians by Ontario trout farmers

This study investigated whether certain variables were associated with Ontario trout farmers' use of the Fish Pathology Laboratory (FPL), Ontario Veterinary College, or their willingness to pay for private veterinary services. Sixty-two farmers, representing 91% of Ontario's 1990 farmed trout production, were personally interviewed. Logistic regression was used to compare the 26 farmers who had submitted fish to the FPL during the previous two years to those who had not. Submitters tended to have been fish farming for fewer years, and to produce more fish, use more workers, treat prophylactically less frequently, keep records of drug treatments, and not disinfect holding units (p<0.05). Most farmers stated they would occasionally hire a private veterinarian. Only 13 farmers anticipated hiring one more than once per year. Polychotomous regression showed that farmers who purchased, instead of hatched, their seed stock, kept records, treated therapeutically often, and used several workers would hire private veterinarians more frequently (p<0.05). Strategies are discussed by which the veterinary profession might better understand and meet the needs of the aquaculture industry.     

Heartworm in dogs in Canada in 1991

In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.     

A pathological and microbiological evaluation of omphalophlebitis in very young calves slaughtered in New Zealand

Omphalophlebitis, generally referred to as navel ill, is a common post-mortem meat inspection finding in very young calves slaughtered in New Zealand, and a gross pathological, histopathological and bacteriological evaluation of 147 carcasses condemned for this condition at routine post-mortem meat inspection was undertaken. Localised lesions restricted to the umbilicus alone were present in 29.9% of cases. The majority of cases included gross pathological change in the umbilical vessels and other tissue sites beyond the umbilicus. Most hepatic nodes were grossly normal but histological examination revealed that 61.5% of nodes from other than localised cases of navel ill were hyperplastic. However, there was little difference in the prevalence of hyperplastic hepatic nodes from cases of localised navel ill (21.4%) compared with normal calves (15.9%). Despite the wide range of bacteria isolated from umbilical lesions, Salmonella typhimurium recovered from the navel, liver and hepatic nodes of a single extended case of navel ill was the only isolation of known public health importance. Given the separation of cases of navel ill into different gross pathological, histopathological and microbiological categories, current meat inspection judgments whereby all calves with navel ill are condemned should be revised. In particular, routine condemnation of the carcass and viscera in all cases of localised navel ill (lesions restricted to the umbilicus alone) should be reassessed.