Bekæmpelse af blodmider hos æglægger

The fight against red mites apparently is an endless task in many types of Layer production systems. Red mites represent a problem for the hens’ well-being and pose a risk of infection, thus regular monitoring and control is recommended.

There are many ways of attacking the red mites and since they spend most of their lives in cracks and crevices, and are dependent on a hot and humid environment, it seems logical to focus on such places. Spider webs and dust shields the mites and should be removed.

A number of egg producers disperse powder, either in the form of silicates, e.g. Hexamid or pure silica, which consists of sharp crystals that supposedly cuts the red mites’ chitin armor into pieces, or use lime based products such as hydrate lime, Stalosan or Staldren. The latter seems particularly interesting because the powder is pH neutral (pH 5.5) and has a drying effect on the environment and the mites, without drying the skin and mucous membranes of hens and humans. Staldren consists of a special grade of calcium carbonate from Faxe Kalk, with various ingredients added, one of which is the disinfectant Halamid imported by the company J.N. Jorenku. During laboratory experiments, the red mites were rapidly disabled when exposed to the powder, as they were dehydrated in a matter of minutes.

In a large cage system facility, with evidence of many red mites, a layer of Staldren was broadcast throughout the facility during the idle period between flocks. The dust settled in a fine, bright red layer over the surfaces of the entire facility. About 6 later a few red mites were still found in the house, but it appeared they were limited to cracks and areas where the powder had not penetrated.

In another egg production facility, broadcasting of Staldren using a motorized backpack type blower, which distributes a fine mist of powder around the facility, was carried out periodically.

This was done in darkness, using a head lamp, and with the hens in the house, without causing any major unrest among the hens. This method is also being tested as a complementary procedure in the facility mentioned above. At the same time, Staldren was added to the bedding material in the sand bath. Three weeks after this, presence of red mites were only detected on plastic clips holding the perches. Further evaluation is on-going.

The project concerning red mite control is sponsored by the Danish Poultry Levy Fund (Fjerkræafgiftsfonden), and J. N. Jorenku has contributed resources to conduct tests using Staldren as a red mite control agent.

* The above text is adapted from an article in Fjerkrænyt (Poultry News) Nr. 19, December 2013 contributed by Ms Susanne Kabell, Consultant & Ph.d. Veterinary.

Kilde: FjerkræNyt nr. December 19, 2013