<P> One obstacle to gathering more comprehensive data on the use of antibiotics in feed is the majority of the poultry industry utilizes vertical integration . As a consequence, farmers are often unaware of what components go into the feed, including whether or not antibiotics are used . Also in antibiotic usage in general, there are criteria to define bacterial resistance to specific antibiotics, however, there are no standards to divide the bacteria into resistant and susceptible categories based on antibiotics utilized . </P> <P> The poultry industry also plays a large part in the United States economy, both in domestic purchasing and through international demand . The USDA reports that the U.S. is the "world's largest producer and second largest exporter of poultry meat ." In 2010, the U.S. produced 36.9 billion pounds of broiler meat and exported 6.8 billion pounds of broiler meat . This equates to an estimated retail value of 45 billion dollars in 2010 . </P> <P> Both the agricultural and pharmaceutical industries have been lobbying against legislation that seeks to quell non-therapeutic antibiotic use in livestock since the first introduction of such legislation in Congress in the 1970s . Despite scientific evidence suggesting a strong association between antibiotic use in poultry and other livestock, agribusiness lobbies such as The National Chicken Council argue that there is not sufficient evidence to purport that there is a measurable impact to humans and shifts the blame of the problem of antibiotic resistance to overprescribing in the field of medicine . </P> <P> With antibiotic restrictions, integrators will bare the immediate costs of these changes, and would likely result in modified finances and contracts with growers . Also, public health agencies may not have adequate scientific evidence for making appropriate decisions for better public health outcomes, secondary to lack of research funds . As a reference, the US spends about $101 billion per year for both governmental and biomedical industrial research, which is only 5% of total health expenditures . </P>

How many chickens are in a typical chicken house