Pest problems have far-reaching effects – Jon Urness, Vita Plus

Posted on May 26, 2016 in Forage Foundations
By Jon Urness, Vita Plus national forage specialist
Wildlife pests found around bunkers, piles and bags are not only an unsightly nuisance, but can also wreak havoc by spreading serious disease threats to livestock and even humans.

Let’s split these threats into two sources:  the airborne threat (birds) and the ground threat (rodents).

Airborne threat
Birds – such as pigeons, starlings, house sparrows and gulls – consume rather large amounts of feed and contaminate much more.  According to USDA, a starling consumes up to 50 percent of its bodyweight in feed daily.  A flock of 200 starlings eats 175 pounds of feed per week, not to mention the feed lost due to contamination.  Because birds have a much higher body temperature than mammals, most bird pathogens don’t seem to bother non-stressed humans and livestock.  However, salmonella and some fungal threats can be serious problems.

  • Salmonella is a bacterial disease-causing organism capable of spreading disease in livestock and humans. Infections are usually intestinal and treatable, but can become more general and cause death.  Young and older cattle are most susceptible, especially two- to four-week-old calves.  In older cattle, abortions and reduced milk production can result. According to USDA, there are 81 known types of salmonella and they can be transmitted through direct contact, consumption of feces-contaminated feed or water, or inhalation.
  • Histoplasmosis and cryptococcosis are diseases found in bird manure.  In the upper Midwest, crypto is probably the most serious of the two and is transmitted by breathing spores, consumption of contaminated feed or water, and even contact with milking equipment. The result is often a mastitis infection that does not respond well to treatment.

Ground threat
Rodents – such as rats, mice, raccoons and opossums – are also sources of destruction and serious disease. Canadian researchers claim that a colony of 100 rats will consume a ton of feed in a year and contaminate or destroy 10 times that amount. Rats create 25,000 droppings per year and mice 17,000, causing all kinds of biosecurity hazards. The researchers state that rodents carry at least 45 different diseases; the most serious include salmonellosis, pasteurellosis, leptospirosis, swine dysentery, trichinosis, toxoplasmosis and rabies.

The economic impact of these pest threats to farms is substantial. USDA estimates that the cost of destroyed feed alone is $2 billion in the U.S.  Stay tuned for the July Forage Foundations when we will explore some ways to fight these airborne and ground threats.

Category: Animal health
Business and economics
Forage Foundations