Prevalence and major causes of ruminal lesions in intensive cattle fattening units.

Ruminal acidosis is frequent in cattle fattening systems associated with grain-rich fibre-poor diets. This study aimed to assess the prevalence of ruminal lesions compatible with ruminal acidosis intensive fattening farms and its risk factors on farm. Rumens of 218 out of 1960 bullocks from six farms were classified in slaughterhouses, and the management practices and the type of feed were compared. The prevalence of lesions compatible with ruminal acidosis was high (65%), where 47% and 18% of the animals had ruminal lesions compatible with subacute and acute disease, respectively. Prevalence of lesions differed significantly between the farms, with differences in the management and feeding practices. Ruminal lesions compatible with ruminal acidosis are prevalent in cattle fattening units in Portugal and husbandry and feeding practices are likely to have an impact.