Growing Forward 2 - Final Report - Page 10

BEEF CATTLE There are approximately 19,000 producers involved in raising beef cattle from birth to market age, with about 325,000 beef cows, in Ontario.1 The average number of cows per farm is between 60 and 70 animals. However, there are a large number of farms with less than 30 cows, and very few farms with greater than 100 cows. As such, the beef industry has a significant economic presence, with over 200 million pounds of beef produced annually, representing roughly $500 million in cattle and calf cash receipts, and contributing more than $2 billion to the Ontario economy. The beef sector usually involves an extensive phase of relatively little intervention, where calves are born and raised through weaning, and periods of more intense management to assemble and finish growth in feedlot conditions. On cow-calf operations, animals generally live on pasture, where disease rates are low, and antimicrobial therapy is rarely used. By contrast, feedlot animals are housed at high densities with intense management. Feedlot cattle are subjected to many stressors, including long-distance shipping, heat or cold, social upheaval, high stocking densities and surgical procedures, such as castration and dehorning. This transition leaves animals vulnerable to infectious diseases, which they are exposed to through mixing with animals from different sources. As such, morbidity in newly received feedlot calves may be as high as 40-50%. There are approximately 19,000 producers involved in raising beef cattle from birth to market age, with about 325,000 beef cows, in Ontario. The major problem affecting stocker and feedlot cattle is respiratory disease. This problem is multi-factorial with many different causal organisms, which are largely normal inhabitants of the upper respiratory tract that have proliferated. Furthermore, these organisms may change in relative importance during the progression of the disease. The feedlot situation makes it challenging to screen newly arrived cattle, particularly since these animals may not show outward signs of illness, and since feedlot managers may have little or no information on the prior health status of the animals. As well, the varied sources of animals make it difficult to ensure consistent health management throughout their life. Feedlots may make use of metaphylactic treatments, based upon the assumption that the animals in the group of high risk and are either susceptible or are already harbouring disease. 1 College of Veterinarians of Ontario‚ÄĀ http://www.ontariobeef.com 10