Antibiotic resistance remains issue

The 2005 DANMAP report from the Danish government’s programme for
surveillance of European antimicrobial resistance, the most recent statistics
available, says: “Antimicrobial consumption in food animals is still low
compared to the total consumption before the cessation of growth promoter use.”
A chart in the report also says antimicrobial use in animals levelled in 2004
and 2005. At the same time, the use of antibiotics in humans has held about
steady from 1997 through 2005, the DANMAP report showed.

US cuts back
on antibiotics
The US Food and Drug
Administration (FDA) says about 70% of infection-causing bacteria are
resistant to at least one of the drugs most commonly used to treat infections in
humans. The FDA site does not say where these bacteria acquired their
resistance, but says use of antibiotics in animal feed can cause microbes to
become resistant to drugs used to treat human illness.

In the US,
sub-therapeutic antibiotic use, or below the level required to cure a sick
animal, in livestock and poultry feed has declined in the last three years,
according to Ron Phillips, vice president of legislative and public affairs for
the Animal Health Institute. Antibiotics are being removed from animal feeds
because consumers want them removed. In July 2005, the FDA removed
its approval for Baytril for use in chicken feed because of its similarity
to human antibiotics and concerns about resistant diseases. “These trends
correspond to an increase in therapeutic use to treat a higher numbers of sick
animals or birds. It “is precisely what is taking place in Europe,” Philips
added.

Farmers and veterinarian response
A Western Kansas
veterinarian with a large cattle feedlot practice said many of his clients
continue to use low-dose antibiotics as growth promoters because they work and
because there are no comparable human drugs in use. In essence, it wouldn’t
matter if the animal’s bacteria developed resistance to these drugs, because the
bacteria still would be susceptible to human drugs, he said.
An Iowa
veterinarian also said there is talk among pig producers of cutting back on
antibiotics in feed, but “it’s a necessary part of production.” They are fed not
only as a growth promoter but to prevent pneumonia and scours, or diarrhoea, he
said.
As if to underscore this need, the FDA recently approved another
antibiotic for feed use in pigs, although it is to be done by “veterinary
directive” only, the Iowa veterinarian said.
The biggest issues in the
cattle industry are whether or not cattle feeders will be allowed to continue to
feed tylosin phosphate (to prevent liver abscesses) and/or monesin (to prevent
coccidiosis, an intestinal disease in cattle),” said Gary Smith, Colorado State
University professor of meat sciences.

The answer: Few and
effective
According to Michael Hansen, senior scientist at the Consumers
Union, which publishes Consumer Reports, the ideal rule-of-thumb is to keep
livestock away from antibiotics unless they are needed, and then to treat as few
as possible with an effective dose.

External
links:
FDA
Consumers
Union

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