RESUMOForam utilizadas 31 vacas leiteiras mestiças para comparar o perfil energético em duas estações, verão e inverno. Amostras de sangue foram colhidas semanalmente durante o pré-parto, no dia do parto e nos dias dois, cinco, 10, 15, 21 e 30 do pós-parto. Todos os metabólitos analisados foram influenciados pelo estádio fisiológico. As concentrações de glicose foram maiores no inverno, enquanto as concentrações de triglicérides e lactato desidrogenase (LDH) foram maiores no verão. As concentrações de colesterol, AST e GGT mostraram um padrão de comportamento diferente entre o verão e o inverno. Ácidos graxos não esterificados (NEFA) e beta-hidroxibutirato (BHB) não foram influenciados pela estação do ano. As vacas que pariram durante o inverno tinham um escore de condição corporal (ECC) maior e perderam mais ECC até o parto. No verão, 32,26% e, no inverno, 29,03% dos animais apresentaram concentrações de NEFA acima do recomendado no pré-parto; 22,58% dos animais no verão e 19,35% no inverno tiveram cetose subclínica em algum momento do período de transição, tornando-os mais suscetíveis a outras doenças.

ABSTRACTWe used 31 crossbreed dairy cows to compare the energetic profile in summer and winter. Blood samples were taken weekly prepartum, at calving and on days 2, 5, 10, 15, 21 and 30 postpartum. All metabolic indicators analyzed were influenced by the physiological status. The glucose concentrations were higher during winter while the triglyceride concentrations and lactate dehydrogenase (LDH) were higher in the summer. The season influenced the concentrations of cholesterol, AST and GGT, showing a different pattern between summer and winter. Non-esterified fatty acids (NEFA) and beta-hidroxibutirate (BHB) were not influenced by the season. Cows that calved during winter had a greater body condition score (BCS) and lost more BCS until calving. During summer, 32.26% of the animals and 29.03% during winter had NEFA concentrations above the optimum level and 22.58% of the animals in summer and 19.35% in the winter had subclinical ketosis at some point during the transition period, making then more susceptible to diseases.

An outbreak of ulcerative abomasitis in suckling calves associated with Clostridium perfrigens type D infection is described. Six twoweek old Holstein calves died after showing loss of appetite and lethargy. Other animals had died in similar circumstances during the previous six months. At necropsy, the abomasum was severely distended with dark fluid and the mucosa was oedematous and covered with many millimetric ulcers, while the serous surface of this organ was covered with fibrin. Several irregular black areas of infarcts were observed in the cecum of one animal. Histologically, the abomasal mucosa showed ulcers and haemorrhage, while the submucosa showed severe oedema and infiltration of neutrophils, lymphocytes and plasma cells. Short, thick, nonsporulated Gram positive rods were observed on smears of abomasal mucosa. C. perfringens type D was isolated from the abomasal mucosa. Low immunity and stress could have contributed to the pathogenesis of the lesions described

Se describe un brote de abomasitis ulcerativa asociada con infección por Clostridium perfringens tipo D en terneros lactantes. Seis terneros Holstein, de 2 semanas de edad, murieron después de presentar anorexia y apatía. Otros animales del mismo establecimiento habían muerto de la misma forma seis meses antes. A la necropsia el abomaso estaba muy distendido con contenido fluido y oscuro, la mucosa estaba edematosa y presentaba gran cantidad de úlceras milimétricas y habían depósitos de fibrina en la serosa. En el ciego de un animal se observaron extensas areas de infarto. En frotis de la mucosa abomasal se observaron bacilos cortos Gram positivos, no esporulados, aislándose de ella un cultivo rico de C. perfringens tipo D. Es probable que la baja inmunidad de los terneros debido a falta de calostro y estrés alimenticio, haya sido el predisponente para la infección por C. perfringens tipo D