Tarsocrural joint polymyxin B concentrations achieved following intravenous regional limb perfusion of the drug via a saphenous vein to healthy standing horses.

OBJECTIVE: To determine whether therapeutic concentrations (> 0.5 to 1.0 µg/mL) of polymyxin B (PB) were achieved in the tarsocrural joint of horses when the drug was administered by IV regional limb perfusion (IV-RLP) via a saphenous vein at doses of 25, 50, and 300 mg and to describe any adverse systemic or local effects associated with such administration. ANIMALS: 9 healthy adult horses. PROCEDURES: In the first of 2 experiments, 6 horses each received 25 and 50 mg of PB by IV-RLP via a saphenous vein with at least 2 weeks between treatments. For each treatment, a tourniquet was placed at the midmetatarsus and another was placed midway between the stifle joint and tarsus. Both tourniquets were removed 30 minutes after the assigned dose was administered. Blood and tarsocrural joint fluid samples were collected for determination of PB concentration before and at predetermined times after drug administration. In experiment 2, 4 horses were administered 300 mg of PB by IV-RLP in 1 randomly selected pelvic limb in a manner identical to that used in experiment 1. RESULTS: For all 3 doses, the mean synovial fluid PB concentration was > 10 times the therapeutic concentration and below the level of quantification at 30 and 1,440 minutes after drug administration, respectively. No adverse systemic or local effects were observed following PB administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that IV-RLP of PB might be a viable alternative for treatment of horses with synovial infections caused by gram-negative bacteria.

Clinical prevalence and associated intraoperative surgical complications of reproductive tract lesions in pot-bellied pigs undergoing ovariohysterectomy: 298 cases (2006-2016).

To address the current dearth of clinically relevant publications regarding ovariohysterectomy (OVH) in the domestic pot-bellied pig (PBP), the present study aims to report prevalence of uterine lesions, intraoperative complications, and short and long-term survival in this species (n=298). Prevalence of lesions included uterine neoplasia 11.4 per cent (34/298), pyometra 1.6 per cent (5/298) and cystic endometrial hyperplasia 5 per cent (15/298). Pigs at least six years of age were statistically more likely to have a uterine lesion (less than P=0.001). Smooth muscle tumours represented the most frequent neoplasm. Haemorrhage was the most common intraoperative complication in 23 per cent (8/34) of pigs with neoplasia. Pigs without reproductive tract lesions were statistically more likely to survive to hospital discharge than those with lesions (P=0.001). Short-term survival, defined as survival to hospital discharge, of pigs with reproductive tract lesions was 89 per cent (48/54). Pigs with pyometra were least likely to survive to discharge 60 per cent (3/5). Long-term survival (≥1 year) was 93 per cent (14/15) for pigs with neoplasia. Practitioners should be aware of significantly higher rate of neoplastic and inflammatory diseases in PBP at least six years of age. To minimise morbidity and mortality in PBP undergoing OVH, the present study suggests the procedure should be performed prior to six years of age.