a b s t r a c tThe aim of the present study was to determine the duration and efficacy of three local anesthetics in the palmar digital (PD) nerve block. Nine adult horses were randomly allocated in a crossover design (bupivacaine, 5 mg/mL; lidocaine, 20 mg/mL; and ropivacaine, 7.5 mg/mL). The objective lameness evaluations were recorded before and at 5, 10,15, 30, 60, 90, 120, 150, 180, 210, 240, and 300 minutes after PD block. The relative lameness severity (RLS) was determined and analyzed using the Tukey-Kramer test (P < .05). Lameness improvement (LI) after blocking was determined as a percentage decrease in the quadratic mean (vector sum). The RLS after lameness induction was 4.06 times the threshold (8.5 mm), and the intensity of lameness (time 0) was similar between horses (coefficient of variance ¼ 25%). Five minutes after PD block, all drugs had improved lameness in more than 2.5 times (LI >60%). Bupivacaine, lidocaine, and ropivacaine were effective in blocking at least three times (LI >75%) the experimental lameness. Using 7.5-mg bupivacaine, LI was >3.5 times between 5 and 90 minutes after PD block (LI >83%). With lidocaine (30 mg), between 5 and 90 minutes after blocking a significant LI was observed with a reduction in the lameness intensity greater than 1.2 times (LI >43%). Ropivacaine (11.25 mg) improved lameness in >2.6 times (LI >66%) between 5 and 180 minutes after block. Bupivacaine and ropivacaine showed greater anesthetic effectiveness when compared with lidocaine. The local anesthetics produced a significant LI 5 minutes after blocking. Objective analysis showed a longer analgesic effect of the PD nerve block using ropivacaine than bupivacaine and lidocaine, respectively.

No abstract

Clostridial myonecrosis is a highly fatal infectious disease of the muscle that is caused by pathogenic clostridia. When it occurs in equine muscle, the infection can cause a variety of clinical signs. The present report described a case of acute myonecrosis caused by Clostridium septicum in a horse, which had a favorable clinical evolution. A 6-year-old mare was admitted to a veterinary hospital due to increased volume and lameness in the left pelvic limb after an intramuscular injection of an anti-inflammatory drug. The diagnosis of myonecrosis caused by C. septicum was based on clinical and laboratory findings. The animal showed significant improvement after 5 months of treatment and was discharged from the hospital. There is very limited information regarding myonecrosis caused by C. septicum in horses in Brazil; our study showed that early diagnosis and prompt appropriate treatment can ensure significant improvement and recovery of affected animals.

No abstract