The morphology and distribution of normally placed and displaced A horizontal cells were studied in the retina of a diurnal hystricomorph rodent, the agouti Dasyprocta aguti. Cells were labeled with anti-calbindin immunocytochemistry. Dendritic-field size reaches a minimum in the visual streak, of about 9,000 microm(2), and increases toward the retinal periphery both in the dorsal and ventral regions. There is a dorsoventral asymmetry, with dorsal cells being larger than ventral cells at equal distances from the streak. The peak value for cell density of 281 +/- 28 cells/mm(2) occurs in the center of the visual streak, decreasing toward the dorsal and ventral retinal periphery, paralleling the increase in dendritic-field size. Along the visual streak, the decline in cell density is less pronounced, remaining between 100-200 cells/mm(2) in the temporal and nasal periphery. Displaced horizontal cells are rare and occur in the retinal periphery. They tend to be smaller than normally placed horizontal cells in the ventral region, whilst no systematic difference was observed between the two cell groups in the dorsal region. Mosaic regularity was studied using nearest-neighbor analysis and the Ripley function. When mosaic regularity was determined removing the displaced horizontal cells, there was a slight increase in the conformity ratio, but the bivariate Ripley function indicated some repulsive dependence between the two mosaics. Both results were near the level of significance. A similar analysis performed in the capybara retina, a closely related hystricomorph rodent bearing a higher density of displaced horizontal cells than found in the agouti, suggested spatial independence between the two mosaics, normally placed versus displaced horizontal cells.

Abstract:The present study reports a snakebite in a horse in the state of Pará, Brazil. At initial evaluation the animal was reluctant to walk and had tachycardia, tachypnea, severe lameness, bleeding on the pastern and swelling around the left hind leg. Blood samples from the bleeding sites, took on the first day, showed leukocytosis and neutrophilia, whereas biochemical values of urea and creatinine were significantly increased. The chosen treatment was snake antivenom, fluid therapy, antibiotics, anti-inflammatory agents and diuretic drugs. On the fourth day of therapy, the hematological values were within normal parameters. There was improvement related to the clinical lameness and swelling of the limb. However, a decrease in water intake and oliguria were observed. On the seventh day the animal died. Necropsy revealed areas of hemorrhagic edema in the left hind limb and ventral abdomen; the kidneys presented equimosis in the capsule, and when cut they were wet. Moreover, the cortex was pale, slightly yellow and the medullary striae had the same aspect. Based on these data, we concluded that the snakebite in the present study was caused by Bothrops spp. and that renal failure contributed to death.

A 300 kg, 11-month-old quarter horse filly was presented with a joint dislocation in the right anterior limb. The animal was attended at the Federal University of Pará (UFPA) Veterinary Hospital in September 2016, where it was reported that the horse was injured on a fence. On clinical examination, the dislocation of the metacarpophalangeal joint with a rupture of the joint capsule and exposure of bone surfaces was observed, however, with no rupture of the extensor and flexor tendons. Surgery was recommended and the patient was anaesthetised with detomidine (Dormiun V; Agener União, São Paulo, Brazil; 0.04 mg/kg), ketamine (Cetamin; Syntec, São Paulo, Brazil; 0.03 mg/kg/h) and guaiacol glyceryl ether (JA Saúde Animal, São Paulo, Brasil, 0.5 ml/kg/h) i.v. The reconstitution of the joint capsule, lateral collateral ligament (LCL) and the other soft tissues around the injury was performed. A chemical arthrodesis was performed, then the tissue approximation and finally the skin suture. Bandages were applied on the wound with hydrophobic cotton and a Robert-Jones dressing. Systemic treatment was performed with enrofloxacin (Zelotril 10%; Agener União, São Paulo, Brazil; 5 mg/kg) i.m., meloxicam (Maxicam 2%; São Paulo, Brasil; 0.6 mg/kg) i.v. during 10 and 20 days, respectively, then replacing the antibiotic with ceftiofur (Cef 50; Agener União, São Paulo, Brasil; 2.2 mg/kg) i.m. for another 22 days. An iodine solution was applied to the joint optimising arthrodesis. After three and a half months, the lesion was entirely healed and with good movement, so the patient was discharged. This case demonstrates that, with adequate treatment and attention, it is possible to recover the patient’s quality of life.