POULTRYAND
LIVESTOCK
POULTRY
The information and recommendations in this newsletter are applicable to
North Carolina
and may not apply in other areas.
I've observed more roach infestations on hog farms over the past few summers. It's hard to say exactly why, but I suspect it has to do with changes in management practices and building design. Whatever the cause, hog house roach infestations are often impressive and always disgusting to anyone who has to work around them. There's plenty of reason for concern. Roaches can transmit almost any disease and parasite that occurs on a hog farm. For example, Salmonella species, E. coli and coccidia are just a few of the pathogens that can be transmitted from room to room in a farrowing house. Cockroaches are the major source of the asthma-causing allergens present in some urban environments. Roaches have even been known to strip wiring and cause electrical shorts. Finally, there's always the possibility of taking some of the insects home.
Fortunately, I've only seen two kinds of roaches on North Carolina hog farms so far. The Oriental cockroach (Blatta orientalis) likes to live in pits, pit plenums, drains, and any place it's warm and damp. These roaches are about 1 inch long as adults and dark brown to black in color. Adult males have wings that don't completely cover their abdomens. Adult females and nymphs of this species are wingless. Oriental cockroaches have the longest life cycle of any of the other pest roaches. It takes 400 to 500 days for these roaches to develop from eggs to reproducing adults. Like all roaches, their eggs are deposited in egg cases called ootheca. The ootheca of this cockroach contains approximately 16 eggs. Each ootheca is carried by the female Oriental cockroach for 1 to 2 days until deposited in secluded areas. Oriental cockroaches are often moved from location to location on infested grocery bags, cartons, feedstuffs, and other items.
The adult German Cockroach (Blattella germanica) is about 1/2 inch long, brown in color, and has two dark stripes on the pronotum (area behind head). Both adult males and females have wings; nymphs are wingless. Like the Oriental cockroach, German cockroaches prefer humid, warm environments. They are not, however, restricted to pits and plenums. German cockroaches readily infest every available space in a farrowing house or nursery. They are found in large numbers inside junction and switch boxes, conduits and light fixtures, behind wall panels, around the compressor under refrigerators, and even inside the frames of farrowing crates. The German cockroach has a relatively short life cycle of 60 to 75 days, and is much more prolific than its cousin. Each of their ootheca contains 30 to 40 eggs. The female German cockroach carries each ootheca around with her until the eggs hatch. Finally, German cockroaches are hitchhikers. They're easily moved around on infested grocery bags, cartons, feedstuffs and other materials.
It's probably not possible to eradicate a roach infestation on most hog farms, but they can be managed. Start with improved sanitation. Make certain that food and trash in offices, break rooms or dining areas are removed every day. Food must be stored in well-sealed containers. Remove clutter (equipment, clothing, trash, etc.) throughout the hog facility. The clutter provides good hiding places for the roaches and makes it harder to apply insecticides efficiently. Also, deny roaches easy entry points and hiding places. Seal gaps around pipes, windows, doors, electrical outlets and conduits with silicon caulking. Close gaps leading to wall voids in a similar manner. Since German and Oriental cockroaches like warm and moist environments, eliminate unnecessary sources of water. Repair all leaks around toilets, water heaters, sinks, flush tanks and other places in the hog house.
Chemical control is usually needed to manage roach infestations. Start keeping accurate records (active ingredients used, application dates, efficacy, etc.) to evaluate efforts and plan rotation of chemicals. Expect to rotate classes of insecticide active ingredient on a regular basis. Roaches are noted for their ability to develop resistance to most of the insecticides used for their control. Rotation of carbamate, organophosphate, permethrin and pyrethrin insecticides will reduce the risk of developing a resistant roach population or compensate for existing resistance problems.
Use the right formulation and equipment to apply insecticides. Wettable powders are often more useful when treating porous surfaces since they adhere to the surface better than emulsifiable concentrates. Apply enough spray to wet surfaces while avoiding runoff. Use low pressure (20 to 40 pounds per square inch) and a flat fan nozzle that gives relatively large droplet size to avoid drift and splash. Dry formulations are more suitable to treat electrical cabinets, junction boxes, wall voids and attics. Use an electrostatic power duster for large areas such as attics.
Treat only those surfaces where roaches are active, but be thorough. In addition to the locations mentioned, drains, plenums, pit walls, under feeders, exterior and interior wall surfaces, walkways, cracks, crevices and other locations are likely targets so long as they are permitted by the product's label. The frequency of application depends on the product used and the type of surface treated. In general, the hog house (especially farrowing rooms and nurseries) is a poor environment for residual control. For example, boric acid is effective for many months if it remains dry, but doesn't work well once it is wet. It is best used in attics and wall voids. Even more versatile insecticides such as chlorpyrifos and permethrin can be easily washed off during clean up. There is also the problem of new roach hatches. Insecticides will not kill eggs, and must be present on surfaces to kill newly hatched roaches. Treatment intervals usually vary from 2 to 4 weeks, but check the label for exact recommendations and follow them. Don't count on two or three treatments for good control. It's likely that treatments will be needed for some time to clean up a serious infestation.
Insecticides registered for use in livestock buildings include the following:
CARBAMATE:
* carbaryl (Sevin); ineffective for German cockroaches
ORGANOPHOSPHATES:
* chlorpyrifos (3M Chlorpyrifos Livestock Premise Spray, Dual Use EC)
* dichlorvos (DDVP, Vapona)
* diazinon (DryZon WP)
PYRETHROIDS:
* permethrin (various trade names)
* cyfluthrin (Tempo, Countdown)
* pyrethrum (various trade names)
Web page last updated on 1 July 1996 by Stephen J. Toth, Jr..
