Field Mastectomy in Ruminants - Surgical and Clinicopathological Aspects

Background: We report the case of 3 cows, 1 ewe, and 1 doe, with chronic mastitis and which underwent a mastectomy. All animals had a history of mastitis, edema with purulent secretion in the udder region, areas of abscess formation, fibrosis, hypogalactia, and agalactia. The animals had already been treated with systemic antibiotic therapy and anti-inflammatory drugs without response. The objective of this work is to describe the surgical and clinicopathological aspects of performing a radical mastectomy in the field in 3 cows and 1 ewe, and a partial mastectomy in a doe, with both procedures performed successfully and considered efficient to maintain the survival of the affected animals, in addition to being economically viable. Cases: In all animals reported in the study, a general and a specific clinical examination were performed, where on palpation of the udder were observed an increase in the region of the mammary apparatus, fluid fluctuation, areas of fibrosis with increased stiffness, and loss of udder functionality. In the case of the doe, there was a functional teat, which was preserved during the surgical procedure. Radical mastectomy was performed in 3 cows and 1 ewe, and the doe underwent a partial mastectomy, with preservation of the functional teat. All animals have fasted for food and water for 48 h. In cows, the anesthetic protocol consisted of 2% xylazine hydrochloride [0.15 mg/kg, intramuscularly (IM)], followed by an epidural block in the lumbosacral region with 2% lidocaine hydrochloride [10 mL]. The midazolam hydrochloride [0.1 mg/kg, intravenously (IV)] and 2% xylazine hydrochloride [0.05 mg/kg, IM] were administered to the ewe and the doe, also associated with lumbosacral epidural anesthesia with 2% lidocaine hydrochloride [5 mL]. The animals were positioned in the right lateral decubitus position and the entire abdominal and udder region were shaved and sanitized for the surgical procedures of radical mastectomy and partial mastectomy, with the use of degerming and topical povidone-iodine. The postoperative period consisted of penicillin-based antibiotic therapy associated with streptomycin [24,000 IU/kg, IM, 10 consecutive days] and flunixin meglumine [2 mg/kg, IM, 3 consecutive days] in cows; enrofloxacin [2.5 mg/kg, IM, 7 consecutive days] and flunixin meglumine [0.5 mg/kg, IM, 5 consecutive days] in the ewe; oxytetracycline [10 mg/kg, IM, 5 applications on alternate days] and flunixin meglumine [0.5 mg/kg, IM, 3 consecutive days] in the doe. In all animals, the cleaning of the surgical wound was performed daily with 10% topical Povidone-iodine and Permethrin ointment, for 14 days, when the stitches were removed. Discussion: The choice of the surgical procedure resulted in improvement of the clinical conditions and increased survival of all animals, and in the case of the doe, partial mastectomy contributed to the preservation of the functional teat, preserving its productive capacity. All anesthetic protocols used and the anatomical positioning of the animals were satisfactory for performing the procedures. Although they are techniques described in the literature with great blood loss, especially in cows, blood transfusion was not required in any of the animals. The stitches were removed 14 days after the surgical procedures, and the surgical wound was completely healed.