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4. Opportunistic Agents

“Shipping fever, or BRD as many call it, is caused by bacteria – that’s why I want to use antibiotics.”






“Yes – but they are ubiquitous opportunitistic bacteria (2) that are present on almost all farms.  This means that they are normally present in low numbers where they wait for an opportunity to overgrow their neighbors and invade the living tissue. Without an opportunity, they typically cause few problems.  Factors that create an opportunity include stress (3), proper housing and viral infections (4). So if we can control these disease precursors, we can reduce the risk of BRD.  You need to inusre good colostrum to newborn calves, maintain a comprehensive vaccination program and follow other good husbandry practices including a good biosecurity program.”



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What is a Backgrounder?

The backgrounder is a person who provides management services that many cow/calf producers omit, such as castrating, dehorning, and vaccinating.  Backgrounders also consolidate calves from many different small producers, get them ready for feedlot and merchandize them to feeders who demand a more uniform group of calves to put on feed.