YDS 2013-1 Soru=50

It is stated in the passage that antibiotics ----.

Farmers in many countries utilize antibiotics in two key
ways: at full strength to treat animals that are sick and in
low doses to fatten meat-producing livestock or to
prevent veterinary illnesses. Although even the proper
use of antibiotics can inadvertently lead to the spread of
drug resistant bacteria, the habit of using a low dose is a
formula for disaster: the treatment provides just enough
antibiotic to kill some but not all bacteria. The germs that
survive are typically those that happen to bear genetic
mutations for resisting the antibiotic. They then
reproduce and exchange genes with other microbial
resisters. As bacteria are found literally everywhere,
resistant strains produced in animals eventually find
their way into people as well. You could not design a
better system for guaranteeing the spread of antibiotic
resistance. To cease the spread, Denmark enforced
tighter rules on the use of antibiotics in the raising of
poultry and other farm animals. The lesson is that
improving animal husbandry – making sure that pens,
stalls and cages are properly cleaned and giving
animals more room or time to mature – offsets the initial
negative impact of limiting antibiotic use.