Rats and mice have long been a problem on farms where food and nesting sites are plentiful. They are carriers of some 45 diseases and are capable of contaminating farm feed and water supplies helping to spread disease from contaminated to uncontaminated areas and from animal to animal. Many of these diseases are harmful to livestock and humans.
You should not be embarrassed to admit you have a rodent problem. The probability is high that mice or rats currently exist on your farm. The embarrassment and costs occur if something is not done to confront the problem.
The general rule of thumb is that there are approximately 25 mice or rats for every one that is seen.
Best Management Practices
The first step is to determine if you are experiencing a mouse or rat problem since they require different control strategies. You can tell what type of rodent you are dealing with by examining the droppings. Mouse droppings are black and rice kernel size and rat droppings are black and bean sized. Both are highly reproductive and extremely capable of surviving in all kinds of conditions.
Step One: Rodent Proof your Barn:
Maintain good housekeeping around and in the barn. Eliminate loosely piled building materials, old feed bags, or anything that a rodent can hide in or under. Block off all entrances into walls and destroy all nesting material.
Remove food and eliminate water sources such as leaky taps, open water troughs, sweating pipes and open drains. Reduce feed spillage and dispose of any dead animal carcasses. Keep all feeds in metal hoppers or covered cans.
Step Two: Control Existing Rodent Population:
Predators – Cats can limit low-level mouse or rat populations. The problem is that cats can introduce disease into your facility by bringing in rodents caught in the fields.
Glue boards – Are effective on mice but you need to avoid excessive dust or they will not work. Need to use caution when removing dead rodents, since there is the chance of disease infection. Be sure to wear gloves and dispose of dead rodents in tightly sealed plastic bags.
Sound and ultrasound devices – Not very effective since rodents may be frightened the first few days by the strange noises but quickly adapt to them.
Traps – Snap or box traps are useful in eliminating rodents. Rats are more distrustful of anything new in their environment and it may take 4-5 days before they are used to the traps. Live traps are good to use near runways used by mice and rats.
Toxic baits (Rodenticides) – There are two types of rodenticides: acute poisons and anti- coagulants. The newer anti-coagulant products require single feedings by rodents to cause mortality. For rats, pre-bait using baits without poison for about one week to get them accustomed to the bail. Baits should be 3-6 ft. apart for mice and 23-33 ft. for rats. All uneaten baits must be removed and properly disposed of after completing the poisoning program. CAUTION: Cover all baits to prevent consumption by children, cats, dogs, poultry and livestock.
It is extremely difficult to eliminate mice and rats from livestock and poultry barns. Always read the labels prior to using a product.
Additional Information on Rodent Control
Baker RO, Bodman GR, Timm RM. Rodent- proof construction and exclusion methods. University of Nebraska. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1025&context=icwdmhandbook
Brittingham MC, Falker ST. Controlling birds around farm buildings. Pennsylvania State University Extension. http://extension.psu.edu/natural-resources/wildlife/wildlife-nuisance-and-damage/birds/wildlife-damage-control-16-controlling-birds-around-farm-buildings
Pierce RA. Bait Stations for Controlling Rats and Mice. University of Missouri Extension. http://extension.missouri.edu/p/G9444
T. Controlling rodents. North Carolina State University Extension. http://www.thepigsite.com/articles/1015/controlling-rodents/
Factsheets in this series were prepared by Stephen Herbert, Masoud Hashemi, Carrie Chickering-Sears, and Sarah Weis in collaboration with Ken Miller, Jacqui Carlevale, Katie Campbell-Nelson, and Zack Zenk.
This publication has been funded in part by Mass. Dept. of Agricultural Resources in a grant to the Massachusetts Farm Bureau Federation, Inc. and by Mass. Dept. of Environmental Protection, s319 Program.