Anyone who visits and works daily on a poultry farm knows that rodents like warm facilities, delicious meals, and temperate water. Everything is free and sometimes readily available. Another gift in the all-inclusive package is that rodents do not face any predators inside the houses. Unfortunately, rodents can hang around and transmit pathogens, including Salmonella spp., infectious bursal disease virus, chicken anemia virus, and inclusion body hepatitis, from other premises and contaminated birds. For these reasons, the presence of rodents creates a high risk of breaking the biosecurity rules.
To Get Rid of Rodents, Learn About Them
- Rats and mice are active at night and hide during the day. However, when the facilities are overcrowded by rodents, they may appear during the day, even when people are working inside the houses. Be aware that the appearance of a mouse or rat during the day can indicate a significant population (some estimate 500 to 1,000). Do not allow them to overrun your facilities. In addition, if the population of rodents is dense, the rodents will compete and disturb breeders, bite them, and eat the eggs and feed.
- Rodents are gnawers, allowing them to wear down their superior incisors, which grow continuously (0.4 millimeter per day). Gnawing on wires can lead to fires due to electrical shorts. Gnawing also can cause equipment damage and accelerated wear of material including egg belts, curtains, and pipes. Rodents also burrow in hidden places under the concrete, causing foundational damage.
- A small hole (only 6 and 12 millimeters) is a welcoming entrance for young mice and rats, respectively.
- Their quick reproductive cycle enables them to increase their population within a short period of time: 7 to 10 litters of mice per year multiplied by 7 to 10 mice per litter.
Three types of rodents typically invade poultry facilities:
- The mouse (Mus musculus) gnaws all the time, is curious, likes to live in the feed storage area, and stays close (less than 50 meters) to the house. Its strong-smelling urine facilitates their detection.
- The black rat, or roof rat, which eats once a day, climbs and hides under the roof. It needs to live close to a water source.
- The Norway rat lives mostly outside. The territorial range for rats is about 100 meters. A rat is suspicious. For instance, arsenic is no longer an effective rodenticide because rats learned that eating the bait led to the death of a housemate! As a result, different rodenticides have been developed including anticoagulants.
Control the Rodent Population
Rodents represent a threat to production from a sanitary and economic point of view. Their entrances must be closed. They are controlled by monitoring the consumption of rodent baits to prevent an infestation. The continuous monitoring and tracking of rodent activity are the only way to prevent an invasion. A good start to control rodents is to use the senses: Look for tracks, fresh gnawing, or musky odors. Species can be distinguished by the shape of their feces: round feces in the case of rats and small sharp feces in the case of mice.
These three pillars can prevent and fight against rodent infestations:
Maintain rodent-proof facilities: For instance, in dark houses, do not allow light leakage. The entrance of light highlights the presence of a hole that could be big enough for mice to gain access. Another common example is the habit of not closing the poultry house door. During egg collection, the main access door can remain open for 1 or 2 hours for daily collection of eggs. Otherwise, the door should remain closed.
Eradicate the rodent nests and eliminate food sources: In the feed storage room, it is not unusual to see some bag leakage and spilt feed on the floor. This is a rodent treat, especially if they can find a water source nearby!
Get rid of rodents as soon as possible: The presence of rodents must be considered an emergency. Indeed, it is easier to eliminate a few mice than a colossal family. Keep in mind that rodents can reproduce starting at 6 weeks old and gestation lasts only 3 weeks. During their life span, the matriarch can produce thousands of progeny.
The key is to prevent hiding and breeding places and sources of food and water for rodents. Ensure premises are kept clean and do not allow any light leakage, especially in a dark house. Create a harsh, inhospitable outside environment by keeping vegetation short and ensuring the disposal of dead birds in a closed and easily cleaned area. Ideally, the farm should be surrounded by a deep concrete wall (50 centimeters in depth) to prevent tunneling under fences. Plain tin sheets and doors as part of the fencing will complete the unwelcoming barriers.
Rodenticides and Bait Stations
Having barriers and rodent stations in place is not enough to deter rodents. Monitoring their presence with the use of rodent baits is obligatory. A map outlining the location of all numbered bait stations must be updated regularly and will help identify the first arrivals. If no rodent activity is found, checking once a week will be sufficient. In the case of an infestation, monitor the bait stations daily and place additional bait stations.