Post-parturient haemoglobinuria in cattle: A Heinz body haemolytic anaemia

Abstract

Extract

During the late summer and spring of the four years 1967 to 1970 many dairy herds throughout the Northland region? ? The Northland region is here regarded as that part of the North Island of New Zealand lying north of Auckland city. There are about 600,000 dairy cattle in this region. experienced outbreaks of a form of post-parturient haemoglobinuria. Clinically the disease was indistinguishable from that reported overseas. In 1970 the first cases occurred in mid-July and the incidence declined sharply towards the end of September, although in both 1969 and 1970 cases were still occurring towards the end of October. In some herds over 40% of the cows showed clinical evidence of the disease. Younger lactating cows, particularly 2- and 3-year-olds, were the more severely affected and most cases occurred 2 to 4 weeks post-partum. The most characteristic clinical feature of the disease was an anaemic state. Practising veterinarians reported that affected animals frequently showed haemoglobinuria, hyperpnoea, pyrexia, icterus, anorexia and decreased milk yield (either singly or in combination), and that occasional animals died with the disease. Intercurrent infectious disease (usually mastitis) was present in some of these fatal cases, while in others there was a history of forced exercise (usually droving with dogs) immediately prior to death.