According to many egg producers and pest control consultants, solid rodent and fly control programs on egg farms that are religiously adhered to can ultimately lead to virtually pest-free layer houses. Robert Rowland, pest control specialist, IVESCO, explained that the pest control success the egg industry has enjoyed will not maintain itself without continued emphasis from producers. “Don’t get complacent; you need to keep doing what you did to get there,” he said. “There has been a little bit of back sliding, but not much. By and large the industry has done a good job of maintaining what they achieved.”
Rowland said that the best way for an egg operation to maintain its pest control program is to have an individual whose sole responsibility is rodent and fly control. “Those are the programs where the maintenance of the program has been quite good,” he said. The layer complex’s full-time pest control specialist may have helpers assigned to them, and Rowland said that some companies have had to hire an additional person just to do the paperwork to stay in compliance with documentation requirements of their programs. “This has definitely increased the cost of eggs,” he said. But complexes can see cost savings in other areas, such as improved bird health and performance over time due to better biosecurity.
Rodents are the most important pest to control to keep Salmonella enteritidis out of the house environment, so Rowland said that egg producers tend to do a better job on rodents, and therefore flies, can, on occasion, become a problem. He said that the majority of any fly issue at a layer operation is going to come from inside the building. If it is a wet year, it is harder to dry out the piles of manure, which makes them more hospitable for fly larvae.
House flies are the main issue at table egg layer farms. In warm weather, the time between when an egg is laid and when the new adult fly is ready to lay eggs is as short as five days. This short generation time in summer months means that fly populations can increase rapidly. In really wet, warm weather, Rowland said that egg producers may have to spray outside the house, but, generally, if egg producers take care of things inside the house, they won’t have to spray outside the house.
Control after a house cleanout
If the house environment is positive for Salmonella enteritidis, then a total house cleanout is required before a new flock is bought into the building. In deep-pit houses this means that the new flock comes into lay without a dry manure pile underneath it to help absorb the moisture in the droppings from the new flock and without the beneficial insects that feed on or parasitize fly eggs, larvae or pupae. Rowland said that most egg producers are not putting an absorptive material in the pits after a total cleanout following an Salmonella enteritidis-positive sample. Those producers that do put something in to absorb manure moisture are using a diatomaceous earth product, bentonite clay or wood shavings.
Rowland said that even without putting absorptive material in the pit, it is still possible to control flies during the critical first eight to 10 weeks that a flock is in the house. “The expense for the first eight to 10 weeks may seem high, but after that, the cost really goes down if you do a good job up front.” In addition to use of a residual spray on the walls and an insect growth restrictor on the manure piles, adding beneficial insects after a total cleanout where you don’t put old manure back in the house can be an important part of a successful fly control program.
Rodents are a harder pest to keep at zero than flies are, according to Rowland. “Rodents are hard to keep out of old houses, and once they get into the manure piles in a deep pit house, they are hard to get rid of,” he said. “A great percentage of people raising table egg layers in the U.S. now do keep the place mowed, and they keep rock around the building. This is really important for the older buildings that are harder to keep the rodents out of.” The rock or gravel around the immediate exterior of the building coupled with keeping the grass outside of the rock area mowed short work together to create a zone that is inhospitable for rodents around the buildings. This reduces the likelihood that they will find a hole in the building to get inside.
Newer buildings with manure belts are designed to be basically rodent-free. “I visited a farm in Pennsylvania that has had two flocks on it, and I found absolutely no evidence of any rodents,” Rowland said. He explained that the high concrete curbs are a good feature of new houses, but rodents can still climb concrete. More important than the height of the concrete curb is that where the metal on the building meets the concrete, there needs to be metal flashing to keep the rodents out.
Broiler and turkey farms also working on pests
Rodent and insect control programs in the poultry industry have been driven by the desire to improve biosecurity and reduce Salmonella numbers on farms. Most of the early successes in pest control were designed and implemented by primary breeders. Rowland said that the success of rodent and insect control in the layer houses has started to spread to broiler and turkey meat bird farms.
Meat bird farms have to work to control rodents and flies, but they also have a pest that has been more difficult to eliminate: darkling beetles. Rowland said he has only seen three meat bird houses that didn’t have any darkling beetles. “Once darkling beetles are in a poultry house, they never leave,” he said. “Any chemical that you use will lead to resistance issues because there are no new genetics in the building.”
Rowland said that houses with concrete floors may have less beetles, but that is not an effective control measure. He explained that beetles are nocturnal and that the broiler industry’s move to solid sidewall housing with low light levels has led to beetles being more active over the 24-hour day. Reusing litter is a deterrent to controlling darkling beetles. The egg load in built-up litter can be enormous. No effective parasite, predator or bait has been found for darkling beetles, according to Rowland. While it may not be practical or possible at the present time to completely eliminate darkling beetles from turkey and broiler houses, Rowland said that with the right timing of chemical applications that beetle numbers can be kept quite low.
Lowering Salmonella numbers on meat bird farms
Rowland said that a number of turkey and broiler integrators are focusing on pest control on contract farms as a means of lowering Salmonella numbers. Many integrators are doing cost share with contract growers on pest control. Some are contracting with local contract applicators to follow a specific program from the integrator to use the chosen chemicals at the right time every flock. This insures consistency on all the farms. “The complex drives the protocol,” he said. “This system seems to work best, results with low cost.”