Studies of the Epidemiology and Risk Factors Involved in the Pathogenesis of Acorn Calf Disease in Australia

Summary

Congenital chondrodystrophy of unknown origin (CCUO) is a condition where a calf from a healthy cow is born with disproportionate dwarfism. In Australia CCUO occurs in beef herds principally in south-eastern NSW and north-eastern Victoria. A sporadic condition until 2001, annual occurrence since, involving higher numbers of affected farms and affected calves, with a few farms outside the focus region is evidence that CCUO is now an emerging condition in southern Australia. As yet the pathogenesis of CCUO is not understood but has been postulated to involve manganese deficiency. 
This project investigated the epidemiology of CCUO in Australia and found that occurrence on affected farms is characterised by a history of maternal nutritional deficiency during gestation in spring calving mobs related to drought (defined as a three-month period in which rainfall is within lowest 10% on record) during the 2nd to 4th months of gestation. An on-farm trial conducted using an injectable multimineral supplement (including manganese, copper, zinc and selenium) did not prevent birth of CCUO calves. At this point extension is needed to support beef producers to recognise, report and prevent CCUO, and further research to delineate the climatic and nutritional conditions that contribute to CCUO occurrence.