Stone brood, or aspergillosis of bees, is a fungal pathology of larvae of different ages and adults. Although the infectious agent is common in nature, the disease is quite rare in bee farms. Its development is observed during the period of active honey collection or in damp spring weather. In this case, the infection can lead to serious consequences. Therefore, the question of how to treat stone brood in bees is considered very relevant.
What is stone brood
This term refers to a fungal disease of the brood, which is most often diagnosed in the spring. The main pathogens of the pathology include Aspergillus flavus Link, fumigatus Fres, niger van Tiegh.
Infected brood cannot leave the comb. It becomes stone and fuses with the cell. As the disease develops, the mycelium affects the body of the individual. Moreover, its main effect is associated with a toxin that changes the structure of soft tissues.
Causes of aspergillosis
Pathogenic fungi lead to the development of aspergillosis. Aspergillus is found on dead individuals and on living plants. They are present on the anthers and nectaries of flowers visited by bees. As a result, the spores, along with the pollen, end up in the hives.
The risk of active fungal development increases at temperatures of +25-45 degrees and humidity at 95-100%. In this case, the pathogens infect the honeycombs and the bees themselves.
Symptoms
It is quite easy to identify stone brood. Infected larvae become covered with a black or brownish-green coating. At the same time, dead individuals acquire a solid consistency.
Adult bees can die not only in the hive itself, but also outside it. In this case, the fungus grows outward, forming a kind of collar behind the head. By pressing on a dead specimen, you can feel the hardening.
Treatment methods
In isolated cases of death of larvae, honeycombs with bees need to be moved to a dry and warm hive. It must be disinfected. After this, special preparations recommended for the treatment of stone brood are used. These include:
- "Ascovet";
- "Astemizole";
- "Askosan";
- "Unisan".
Only Unisan is suitable for independent use.In this case, 1.5 milliliters of the substance must be mixed with 750 milliliters of sugar syrup. It is recommended to use the resulting solution to treat the following:
- internal walls of the hive;
- frames on both sides;
- empty and occupied cells;
- bee colonies with brood;
- beekeeper's work clothes and tools.
The manipulation should be repeated 3-4 times with an interval of 7-10 days. It is recommended to complete the processing 20 days before the start of honey collection.
If bee colonies are severely damaged, they must be destroyed. For this purpose, smoking with sulfur dioxide or formaldehyde is used. Insulation, canvases and frames must be burned. Then you need to process the hives and tools. To do this you need to do the following:
- Clean the hives from debris, insect corpses, wax, and fungi.
- Treat surfaces with a 5% formaldehyde solution.
- Dig up the soil under the hives, adding a 4% formaldehyde solution.
- Disinfect gowns, towels, and face masks. To do this, you need to boil for half an hour or soak things in a 2% hydrogen peroxide solution for 3 hours. After which they should be washed and dried.
Prevention
To avoid the appearance of stone brood in bees, it is recommended to adhere to the following rules:
- Before installing the hives, the land should be treated with lime. This should be done for disinfection purposes.
- Maintain exceptionally strong bee colonies in the apiary.
- Place the apiary in dry places that are well lit by the sun.
- Avoid dense grass.
- For the winter, reduce the number of nests and insulate them well.
- During the period of absence of honey collection, provide the bees with nutritious food.
- Keep houses dry, clean and ventilated.
- Do not carry out any manipulations with hives in damp and cold weather.
- Do not use antibacterial drugs that weaken the immune system of insects to strengthen bee colonies.
High humidity in hives poses a great danger to bees and can cause the development of a fatal disease. Therefore, the houses in the apiary must be dry and warm throughout the year.
Stone brood is considered a rather dangerous disease, which leads to negative consequences for bees and can provoke their death. Therefore, when the first signs of a fungal infection appear, it is worth taking action.
