Amputation and Cisplatin for Treatment of Canine Osteosarcoma

Seventy-one dogs with histologically confirmed appendicular osteosarcoma were evaluated. Seventeen dogs were treated with amputation and two postoperative [corrected] doses of IV cisplatin given 21 days apart (group 1). Nineteen dogs were treated with IV cisplatin 21 days before amputation, with a second dose given immediately after amputation (group 2). Thirty-five dogs were treated by amputation of the affected limb with no chemotherapy (group 3). The median disease-free interval for group 1 was 226 days, and 177 days for group 2. This was not significantly different. The median survival time was 262 days for group 1, 282 days for group 2 and 119 days for group 3. Group 1 and 2 dogs had survival times that were significantly longer than for dogs in group 3. Two IV courses of cisplatin given before or after amputation appears to improve the survival of dogs with osteosarcoma.     

Toxicoses associated with administration of mitoxantrone to dogs with malignant tumors

One hundred twenty-nine dogs with histologically confirmed malignant tumors were used in a prospective study to determine the toxicity of the new dihydroxyquinone derivative of anthracene, mitoxantrone, which was administered IV at 21-day intervals at dosages ranging from 2.5 to 5 mg/m2 body surface area. Each dog was evaluated for signs of toxicosis for 3 weeks after each dose was administered or until the dog died, whichever came first. The number of dogs in each evaluation period were as follows: 1 dose (n = 129), 2 doses (n = 82), 3 doses (n = 43), 4 doses (n = 26), 5 doses (n = 19), 6 doses (n = 9), 7 doses (n = 6), 8 doses (n = 5), 9 doses (n = 3), and 10 doses (n = 1). The most common signs of toxicosis were vomiting, diarrhea, anorexia, and sepsis secondary to myelosuppression. None of the dogs died of complications resulting from mitoxantrone treatment. Dogs with signs of toxicosis during the 21-day interval from administration of the first dose of mitoxantrone were 95 times (P = 0.003) more likely to develop signs of toxicosis during the 21-day interval from the second dose of mitoxantrone. Similarly, dogs that developed signs of toxicosis during the 21-day interval from the administration of the second dose were 34 times (P less than 0.001) more likely to develop signs of toxicosis during the 21-day interval from the administration of the third dose. With each 1 mg/m2 increase in mitoxantrone, the odds of developing signs of toxicosis increased by 5.9 fold (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Response of Canine Mast Cell Tumors to Treatment With Oral Prednisone

Twenty-five dogs with naturally occurring mast cell tumors were treated with daily oral prednisone (1 mg/kg) for 28 days. Five dogs (20%) had reduction in tumor volume and were considered responders. Four of these underwent partial remission and one underwent complete remission. Survival times for the five responders were 3, 5, 6, 7.5, and greater than 28 months, respectively. We therefore conclude that prednisone is effective in some canine mast cell tumors. Further studies are indicated to determine the most effective dose of prednisone, the appropriate duration of treatment, and the efficacy in more benign mast cell tumors, and in combination with other forms of therapy.     

Radiotherapy of soft tissue sarcomas in dogs

Megavoltage radiotherapy was administered to 42 dogs with soft tissue sarcoma. Acceptable local control of these aggressive tumors was achieved after one year of treatment. Control rates of 48 and 67% were obtained at doses of 45 and 50 gray (Gy), respectively. At 2 years, control rates decreased to 33% at the dose of 50 Gy. Serious complications developed in 4 of 42 dogs at doses of 40 to 50 Gy. The estimated dose with a 50% probability for causing serious complications was 54 Gy, given in 10 fractions. We believe that the large doses per fraction used in this study probably led to an increased probability for necrosis. Hemangiopericytomas seemed to be more responsive than fibrosarcomas. Only 2 of 11 recurrent tumors were controlled with surgery. Good local control was achieved with radiation alone for one year at doses with a low probability for serious complications; however, higher total radiation doses or combined modalities, such as surgery and radiation or radiation and hyperthermia, may be needed for longer-term control.     

Outcome of dogs with high-grade soft tissue sarcomas treated with and without adjuvant doxorubicin chemotherapy: 39 cases (1996-2004)

OBJECTIVE: To examine the effect of adjuvant doxorubicin chemotherapy on outcome in dogs with high-grade (grade 3) soft tissue sarcomas (HGSTSs). DESIGN: Retrospective case series. ANIMALS: 39 dogs. PROCEDURES: Medical records of dogs with HGSTSs were reviewed. Dogs treated with surgery alone or receiving single-agent doxorubicin chemotherapy postoperatively were included in the study. Owners and referring veterinarians were contacted for follow-up information. Slides from histologic sections were reviewed to confirm the diagnosis of HGSTSs. Cases in which follow-up examination was not performed and radiation therapy or chemotherapy other than doxorubicin was administered were excluded. RESULTS: 39 dogs met inclusion criteria. Twenty-one dogs received adjuvant doxorubicin. Tumor-, patient-, and treatment-related variables were not significantly associated with measured outcomes including local, metastatic, and overall disease-free intervals as well as survival time. Overall median disease-free interval was 724 days with a median survival time of 856 days for all dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Adjuvant doxorubicin-based chemotherapy did not benefit this population of dogs with HGSTSs. Outcome for visceral HGSTSs was similar to that of nonvisceral HGSTSs in these cases.     

The structure and regulation of the Irish equine industries: Links to considerations of equine welfare

The equine industries in Ireland are vibrant and growing. They are broadly classified into two sectors: Thoroughbred racing, and sports and leisure. This paper describes these sectors in terms of governance, education and training in equine welfare, and available data concerning horse numbers, identification, traceability and disposal. Animal welfare, and specifically equine welfare, has received increasing attention internationally. There is general acceptance of concepts such as animal needs and persons' responsibilities toward animals in their care, as expressed in the 'Five Freedoms'. As yet, little has been published on standards of equine welfare pertaining to Ireland, or on measures to address welfare issues here. This paper highlights the central role of horse identification and legal registration of ownership to safeguard the health and welfare of horses.     

Trends in cow numbers and culling rate in the Irish cattle population, 2003 to 2006

Cows are the main economic production units of Ireland's cattle industry. Therefore, demographic information, including overall numbers and survival rates, are relevant to the Irish agricultural industry. However, few data are available on the demographics of cows within a national population, either in Ireland or elsewhere, despite the recent development of comprehensive national cattle databases in many EU Member States. This study has sought: to determine the rate of cow culling from the national herd; to determine the rate of culling by type (dairy, beef), age, method of exit, date of exit and interval between last calving and exit; to calculate the national cow on-farm mortality rate; and to compare the Irish rates with published data from other countries. This work was conducted using data recorded in the national Cattle Movement Monitoring System (CMMS). Culling refers to the exit of cows from the national herd, as a result of death but regardless of reason, and cow-culling rate was calculated as the number of cow exits (as defined above) each year divided by the number of calf births in the same year. Culling rate was determined by type (dairy or beef), date of birth, method of exit (slaughter or on-farm death), month of exit and interval between last calving and exit. The average cow-culling rate during 2003 to 2006 was 19.6% (21.3% for dairy, 18% for beef). While comparisons must be treated with caution, it concluded that the overall rates of culling in Ireland fell within published internationally accepted norms. The on-farm mortality rate of 3.2-4.1% was similar to that reported in comparable studies.     

Tuberculosis in alpaca (Lama pacos) on a farm in Ireland. 2. Results of an epidemiological investigation

Tuberculosis (TB), due to infection with Mycobacterium bovis was diagnosed in a flock of alpaca in Ireland in 2004. An epidemiological investigation was conducted to identify the risk of TB for farmed alpaca where TB is endemic, the origin of the infection, the potential for alpaca-to-alpaca transmission and appropriate control measures. The investigation focused on the alpaca flock (including the farm, animal movements and breeding, feeding and flock health practice), the disease episode (including animal disease events and subsequent control measures) and TB infection risk in the locality. The TB risk to alpaca is high in areas where infection is endemic in cattle and badgers and where biosecurity is inadequate. It is most likely that the source of infection for the alpaca was a local strain of M. bovis, present in cattle in this area since at least 2001. Genotyping of isolates identified a single variable number tandem repeat (VNTR) profile in both cattle and alpaca in this region. Although a tuberculous badger was also removed from the vicinity, bacterial isolation was not attempted. On this farm, infection in alpaca was probably derived from a common source. Alpaca-to-alpaca transmission seems unlikely. Two broad control strategies were implemented, aimed at the rapid removal of infected (and potentially infectious) animals and the implementation of measures to limit transmission. Tests that proved useful in detecting potentially-infected animals included measurement of the albumin-to-globulin ratio and regular body condition scoring. Skin testing was time consuming and unproductive, and early detection of infected animals remains a challenge. The flock was managed as a series of separate groupings, based on perceived infection risk. No further TB cases have been detected.