University of Minnesota professor of veterinary medicine, Randall Singer, said many antibiotics are naturally produced by bacteria or fungi that help kill or inhibit the growth of microorganisms during a session at the Iowa Pork Congress held in Des Moines recently, reports High Plains/Midwest Ag Journal.

He said: "Antibiotics have several different approvals in the US. Use for growth promotion and feed efficiency is at a low dose to help improve the health of animals. Use as disease prevention, is also administered at a low dose to healthy animals who are at risk for catching a disease. Use for disease control is at a higher level when one or more animals have contracted the disease. And use for disease treatment is at a high level when the animal is already sick and needs treated."

While some mutant strains of diseases have been found, Professor Singer says antibiotics are not causing the mutant strains in all cases.

He continued: "The pathogens don't always cause disease. They are opportunistic and cause disease when something else present is causing it. Prior use of high amounts of antibiotics is causing the risk of more disease."

Professor Singer said when antibiotics are used at high doses, all the bacteria in the gut are killed that protects animals from other disease. However, using low doses of antibiotics is a better option because it helps prevent or treat the problem disease in early stages.

"The huge problem here is that the wrong people use only part of the information inappropriately to lead to an antibiotic ban," he added.

The research shows that low doses of antibiotics over long periods of time are better with better susceptibility to disease, according to Professor Singer. High doses of antibiotics will kill off more susceptible bacteria and make animals more prone to disease.

He noted the ban of antibiotics in Denmark in the late 1990s, which they thought would help improve human health.

"The Danes have seen an increase in diseases resistant to medications such as tetracycline and chloramphenicol since the ban," he said. "The antibiotic ban in Denmark got rid of the use of antibiotics at low levels as feed additives. The interesting fact that is not reported is that the actual doses of antibiotics in Denmark have skyrocketed. These doses must be given at high levels to fight the diseases, when these diseases could actually be less prevalent if antibiotics were given at low levels in feed."

Hog producers in Denmark can still use high doses of antibiotics therapeutically and they are using more antibiotics now at high levels to treat hogs that are disease-prone because bacteria in the gut has been killed.

"Would you rather keep your animals healthy in the first place or use antibiotics at high levels to treat sick animals and risk human health?" asked Professor Singer. "The answer to that is fairly easy in my mind, but we are looking at regulations against all the 'possibilities' instead of using facts."

Iowa State University veterinary medicine professor, Scott Hurd, said the issues that are being looked at are about antibiotic resistance, not antibiotic residues, reports High Plains/Midwest Ag Journal.

"Science tells us that the risk for humans' health to be affected from antibiotic use in animals is minimal," he said.

Professor Hurd said using science is not the same thing as using scientific material and it is important to know the risk that is imposed.

He said the most important thing to do before making any drastic decisions is to do a risk assessment of the situation and what is involved.

"The fact is that you are actually more likely to die from a bee sting than from an antibiotic-resistant bacteria. So maybe we should outlaw bees," Professor Hurd joked.

Politicians in Denmark and other European nations have banned the use of antibiotics because they think it will make an improvement in human health when, he said, it is most important to have healthy animals because "healthy animals make safer food."

"If we can remove illness from animals then we will have healthier animals and safer food," Professor Hurd said.

He pointed out that the public health risk is more from unhealthy animals than ones who have had low doses of antibiotics.

"A carcass with adhesions from disease or sickness is 90 per cent more likely to be contaminated with salmonella, which can lead to contamination of surrounding carcasses due to cut-outs of contaminated areas," he continued. "If we have healthy animals we reduce this risk considerably."

Professor Hurd said he hopes bans are not put on antibiotics and realistically, he expects more veterinary oversight of antibiotics in the future. He also thinks producers will need to keep better records in order to prove what medicines they have given which animals and when.

"With the continual demand for food and an increase in consumption of meat, people want to eat meat and it is our job to give them a healthy, wholesome product," he said.

With evidence of effectiveness of antibiotic use at low levels, Professor Hurd does not expect to see any federal legislation regarding antibiotics as long as producers continue to use antibiotics correctly and carefully, reports High Plains/Midwest Ag Journal.

"The government and consumers don't always know what is good for them. US pork producers need to continue to fight the good fight to raise healthy animals, which will make safe food," he concluded.