This summer’s high temperatures have created major problems in terms of controlling flies on livestock units all over the country, with many producers struggling to stay on top of a critical issue, says David Reece, Technical Adviser to Lodi UK.
Apart from the irritation they cause, preventing poultry, pigs, cattle and other livestock from settling and feeding, flies can cause physical damage by biting and transmitting organisms, viruses and diseases. Issues with animal welfare, biosecurity, reduced productivity and environmental complaints are common where flies proliferate, so controlling them effectively is essential on any professional livestock business.
This summer has provided ideal conditions for flies to breed and thrive. Day- and night-time temperatures have been much higher than normal, so flies have bred very successfully, and a high percentage of their eggs have developed into maggots.
The cold spring meant that the normal build-up in flies during April did not happen, but when average temperatures began to rise sharply in June their numbers escalated rapidly. Complaints from home owners living close to livestock units rose sharply as windows were left open to combat the heat, as did the number of producers requiring help to control sudden increases in fly numbers.
The main species which affect livestock are the common house fly (Musca domestica), lesser house fly (Fannia canicularis) and stable fly (Stomoxys calcitrans). All like a consistent temperature and their level of activity depends more on a rise in the average temperature than peak figures. As soon as the average night-time temperature rises to threshold levels they tend to become active.
Flies are prolific breeders and have been able to produce another generation on an almost weekly basis this summer. In many cases, numbers went from zero to problem levels in a very short space of time, requiring a fast response followed by more frequent control measures. In previous years it might have been possible to wait a week before acting, but this year 24 - 48 hours has often been the limit. And where normally pest controllers might visit regular customers every six weeks this has often been reduced to perhaps four weeks.
Regularly monitoring fly numbers and activity are key to staying on top of the problem and should be done at least weekly until the average night-time temperature falls to below 8°C. Just as fly numbers only increase when the average temperature starts to increase over time, conversely, numbers only begin to decline when the average temperature begins to decline over time.
Whilst controlling adult flies may look impressive in terms of visual results by the time they reach that stage they will have produced the next generation. This approach is therefore unlikely to be the best long-term option, it is expensive due to the need for ongoing treatment and should be limiting to minimise the risk of building up resistance to the active ingredients used in these types of product.
A more effective, cost-efficient method for most livestock enterprises is to treat manures with a modern, flexible and effective larvicide product such as LodiMaggots, which tackles the problem at base level by killing fly eggs and maggots to eliminate and control fly larvae. An alternative is Lodi Sheila RB1, a ready-to-use Azamethiphos-based granular insecticide which contains unique sex pheromones and attractants that lure flies to the bait, killing them quickly.
In warm, still areas inside livestock housing where flies congregate to rest and breed Lodi Twenty One, the only product that can be sprayed or painted on the walls and ceilings of livestock buildings, can be used to kill flies almost instantly. Lodi Perbio Choc RTU instantly kills all flying and crawling insects including red mite.
Further information is available from Lodi UK on 01384 404242 or www.lodi-uk.com