Influência da raça sobre a volemia e função renal de bovinos com acidose láctica ruminal aguda, induzida experimentalmente | Influence of the breed on volemia and renal function in cattle with experimentally induced acute rumen lactic acidosis

Portugués. A volemia e a função renal de bovinos com acidose láctica ruminal (ALR) foram estudadas em cinco garrotes Jersey (J) (Bos taurus) e cinco Gir (G) (Bos indicus). Amostras de sangue, urina e conteúdo ruminal foram coletadas durante 24h após a indução experimental da ALR. Os bovinos G apresentaram maior grau de hipovolemia (p < 0,00001) e volume ruminal (p ; 0,47) na excreção total diária deste isômero; garrotes G excretaram menor quantidade de lactato-L na urina (p < 0,05). Independente da raça, quanto menor foi o pH urinário maior a porcentagem de excreção fracionada urinária de lactato total e de lactato-D (r = - 0,69).

Inglés. To study volemia and renal function in cattle with acute rumen lactic acidosis (RLA) five Jersey (J) (Bos taurus) and five Gir (G) (Bos indicus) steers were used. Blood, urine and ruminal fluid samples were collected throughout 24h after RLA induction. Higher levels of hipovolemia (p < 0.00001), and total rumen volume (p < 0.05), lower glomerular filtration (p < 0.003) and urinary volume (p < 0.05) were detected in the G steers. Nevertheless, these steers excreted more efficiently H+(p < 0.0001); although higher urinary D-lactate fractional excretion was seen in the G steers similar amounts of D-lactate were excreted by both breeds throughout the trial. Lower urinary levels of L-lactate were excreted by G steers. The higher the urinary pH, the lower the D-lactate fractional excretion in both breeds.