Date of this Version
Commensal rats and mice are among the only animals about which no good can be said. Each year rats and mice are estimated to cost the American public over $1 billion. This loss is due to contamination of food stuff, structural damage, etc. To give an idea how these rodents can effect the economic picture, assume a rat will eat 25 pounds of chicken feed per year and foul another 25 pounds to such extent it cannot be used as feed (some estimates are as much as ten times greater). The house mouse will consume about 5 pounds per year. Feed costs are not constant; they differ from time to time over quite a range. If feed costs $120 per ton, then each rat costs $3 a year to feed, a mouse, 30 cents.