Therapeutic efficacy of tilmicosin in ovine mammary infections

The therapeutic activity of tilmicosin was studied in some bacterial infections responsible for mastitis and mammary pustular dermatitis in sheep. The research was carried out on 105 half-breed sheep, between 3- and 5-year-old, kept in loose housing. The animals were divided into two groups (A and B) on the basis of clinical signs observed. Group A (68 animals suffering from mastitis) presented with the udder increased in volume, reddened, hot and painful on palpation, with decreased mammary secretion. Group B (37 animals suffering from mammary pustular dermatitis, aggravated by symptoms of mastitis), presented with vesicles and pustules all over the skin of the udder and the teats. Both groups were treated with tilmicosin (Micotil® Elanco). The results obtained in vitro and in vivo confirmed the therapeutic effectiveness of this antibiotic in both groups. A single dose of tilmicosin (10 mg/kg body weight (b.w.) subcutaneously) can be used with efficacy and safety in bacterial mastitis and in mammary pustular dermatitis caused, respectively by Staphylococcus aureus, coagulate negative staphylococci and Staphylococcus epidermidis (isolated by bacteriological test). Moreover, the greater susceptibility of these staphylococci to tilmicosin than to various other antibiotics tested in vitro (cephalotin, cloxacillin, enrofloxacin, gentamicin, tetracycline, thiamphenicol) make it an excellent choice for the treatment of this infection. In both groups of treated animals, the symptomatology decreased rapidly and completely with remission and normal functioning of the udder after 5 days of the treatment. No bacteria were present in milk 5-7 days after administration. None of the treated animals showed local or general side effects. However, the long-term efficacy of tilmicosin on maintaining a bacteria-free status of the udder beyond day 11 is unknown and requires further investigation. © 2003 Elsevier Science B.V. All rights reserved.