Prevalence of bovine milk pathogens in Azorean pastures: mobile versus fixed milking machines

The aims of the present study were (1) to evaluate the influence of using mobile (n=47) or fixed (n=45) milking machines in Azorean herds on the apparent prevalence of several milk pathogens in bulk tank milk (BTM) and (2) to determine whether separated subclinical mastitic cows can serve, in real time, as predictors of milk pathogen prevalence for the remaining animals at the herd level. The use of a mobile or fixed milking machine influenced (P≤0.05) the prevalence of Staphylococcus aureus (72.3 per cent; n=34 v 51.1 per cent; n=23, respectively) and Klebsiella species (46.8 per cent; n=22 v 26.7 per cent; n=12, respectively). S aureus (95 per cent CI OR 1.1 to 6.0) and Klebsiella species (95 per cent CI OR 1.0 to 5.8) were 2.5 times more likely to increase in the BTM of herds using mobile milking machines. The prevalence of coagulase-negative staphylococci (100 per cent; n=92), Escherichia coli (75.0 per cent), Corynebacterium bovis (57.6 per cent), Enterococcus species (55.4 per cent), Streptococcus dysgalactiae (51.1 per cent), Streptococcus uberis (41.3 per cent), Actinomyces pyogenes or Peptostreptococcus indolicus (41.3 per cent) and Streptococcus agalactiae (32.6 per cent) in BTM remained similar among the herds. κ coefficients were always <0.70, indicating intra-herd disagreement of the prevalence of milk pathogens between BTM and separated milking cows. Milking hygiene should be improved in pastures, focusing specifically on herds that use a mobile milking machine. The segregated cows at milking time are not good predictors of milk pathogens in BTM.

Treatment of skin carcinomas of the face by high-dose-rate brachytherapy and custom-made surface molds

PURPOSE

To analyze the results obtained in a prospective group of patients with basal or squamous cell skin carcinomas of the face treated by high-dose-rate (HDR) brachytherapy via custom-made surface molds.

METHODS AND MATERIALS

A total of 136 patients with basal or squamous cell carcinomas of the face were treated between March 1992 and March 1997 by surface molds and HDR brachytherapy with iridium-192. Nineteen patients were treated with standard Brock applicators and 117 patients with custom-made polymethyl methacrylate applicators, built over a plaster mold obtained of the patient's face. Minimum dose administered to the tumor was 6000 to 6500 cGy in 33 to 36 fractions at 180 cGy/fraction in lesions of up to 4 cm. Lesions greater than 4 cm were boosted up to 7500-8000 cGy after a 3-week pause.

RESULTS

With the custom-made surface molds, the dose distribution was uniform in the surface of the skin and at 5 mm depth in the whole area of the applicator. Differences between the areas of maximum and minimum dose at this depth never reached values higher than 5% of the prescribed dose. At the edges of the custom-made molds dose gradient was sharp, with the detected dose at 5 mm from the applicator being negligible. All the patients were complete responders. There were 3 local recurrences, 1/73 patients treated for primary tumor and 2/63 patients treated for recurrent tumor. Actuarial local control at 5 years for all patients was 98%, for those patients with primary tumors 99%, and for recurrent patients 87%. The treatment tolerance was excellent in all cases. No severe, early, or late, complications were detected.

CONCLUSIONS

Radiotherapy is a highly effective treatment of skin carcinomas of the face. Custom-made molds, to be used in conjunction with HDR brachytherapy equipment, make possible a uniform dose distribution, with a sharp dose gradient in the limits of applicators. Custom-made surface molds are easy and safe to use, and they fit very accurately for daily treatment. Local control is excellent with minimal sequelae or complications. Probably they will become the standard way of treatment of face skin carcinomas in the near future.