POULTRYAND
LIVESTOCK
POULTRY
The information and recommendations in this newsletter are applicable to
North Carolina
and may not apply in other areas.
The Norway rat, Rattus norvegicus, is potentially one of the most serious pests of livestock and poultry production. They consume and ruin feed, destroy foundations with their burrowing, chew through electrical wiring, can spread livestock and poultry diseases, and have been known to kill young chickens and turkeys. Fortunately, rats are much easier to control than mice.
Start rat control programs by doing what should be done to discourage all rodent invasions: clean up around the place. Cut tall weeds growing against buildings, along nearby fence lines and drainage ditches, and on lagoon banks. Properly store or remove lumber, spare feeders and all that other objects you just might need that has collected around the outside of your buildings. Even a cluttered room inside a building can be a rodent haven and should be cleaned up.
A good general cleaning accomplishes two goals. First, it discourages new rodent immigrants by taking away the easy hiding places. Secondly, and most importantly, it makes it much easier to locate rodent burrows. This is particularly true for the Norway rat since it nests almost exclusively below ground. The large burrows of Norway rats are pretty easy to spot if there's no place to hide them. Successful rat control depends on locating all of the burrows. It's much easier and more effective to bait Norway rats where they live than placing baits where they may go once they leave their burrows at night.
The first step for Norway rat control is a survey of the area to locate all of the rat burrows. I find it helpful to carry a few bundles of surveyor flags to mark each burrow. While locating and marking burrows, take a second to close each one (a boot heel works just fine). Walk the perimeter of buildings. Check around feed bins, pump houses and storage sheds. Also walk fence rows and tree lines within 100 feet of a poultry or hog house (or any other animal structure and outbuilding). Inspect nearby drainage ditches for burrows. If there's a lagoon, check along the banks for rat burrows. Most lagoon bank rat burrows are found on the bank nearest poultry and hog houses.
Keep a running inventory of the number of burrows that you locate. Use this count to estimate how much rodenticide will be needed. Calculate your needs by multiplying the number of burrows by three. That's the number of days of consecutive baiting needed for one baiting cycle when using a single dose rodenticide. Single dose active ingredients include brodifacoum, bromodiolone, bromethalin, cholecalciferol and difethialone. Choose pelleted baits in individual packets (pitch packs). That's probably the most economical choice. Add another 50 percent (that's my estimate) tothe total number of bait packets needed to cover a second cycle of baiting. It's now time to bait some rats.
The baiting method recommended is called pulse baiting. It's very simple, but effective when done properly. Start by inspecting each of the burrows marked earlier. Re-close open burrows and inspect them again after 24 hours. Remove flags from burrows that have not been reopened, and bait each open burrow with a single pitch pack. Open is the operative word here. Basically, if the burrow stays closed after 24 hours, it's dead. If it's open, there's still someone home. Be sure the packet is pushed into the burrow. It doesn't have to be wedged tight, but should be squarely in the rat's tunnel. This improves the likelihood that the rat will take the packet into its burrow or open the packet and feed where it's found. Pitch packs placed well into the rat's burrow are also less likely to be rooted out by a non-target animal.
Inspect burrows the following day, and replace pitch packs as needed. Some packs will be gone, some will be untouched, and others partially eaten. Some will look intact, but will be completely empty. The lesson here is to be sure that each visible pack still has bait in it. If desired, check and re-bait burrows for a third day. Once daily baiting has gone on for 2-3 days, forget about the rats for one week. Return the following week to start another baiting cycle (pulse) as described. A third cycle may be needed, but the rat population will be greatly reduced by that third week.
Occasionally, it is not possible to reach a particular rat burrow
or group of burrows. It will be necessary to bait the approaches
to these burrows, by placing pitch packs in some suitable bait
station. Rat-sized commercial bait stations are available from many agriculture supply stores. Homemade stations are easily constructed from 3 inch drain tile cut into 24 to 36 inch long sections. To be effective, stations must be placed along rat "runways". Rodents hug the walls as a general rule, so position bait stations flush against walls with their openings aligned along the wall (note the positioning of the homemade bait station). Several stations located along walls as close as possible to inaccessible rat burrows will generally work.
I want to briefly mention a potential problem for hog producers called PADS (Porcine Allergic Dermatitis Syndrome). Thanks to the rainfall that's occurred recently over much of North Carolina, the mosquito populations will increase dramatically. All the female mosquitoes will be hungry, and some of them will feed on hogs. White-skinned hog breeds can be particularly sensitive to mosquito bites and often develop small red lesions at the bite sites. When there are a lot of bites, and the skin reaction is serious, it's called PADS. Top hogs that show up at slaughter with PADS are often docked severely. The condition is short-lived (no more than a few days to a week), but will be recurring if the mosquitoes are not controlled.
Premise sprays with permethrins are effective to reduce mosquito populations. Apply sprays at labelled rates to interior and exterior surfaces (under eaves, in corners and other dark, protected spaces around the building). Top hogs may also be sprayed at the appropriate rate to kill and repel feeding mosquitoes. Treatments need not be applied more than 3 to 4 days before hogs go to market unless the hogs are being severely challenged by the mos8quitoes. Remember, however, that there are treatment intervals relating to both structures and animals. Don't overdo it.
One other alternative that may work to reduce mosquito pressure on animals due for market is to increase wind speed. Try positioning fans to maintain a constant, high velocity air flow for several days over the hogs going to market. The air flow should discourage mosquitoes from settling in for a meal. Note that this last suggestion is only my opinion based on what I know about mosquitoes around hog and poultry farms. This is not a technique that's been researched.
Web page last updated on September 16, 1996 by Stephen J. Toth, Jr..
