Diseases of bees / Ministry of Agriculture and Fisheries.

Date:
1948
Catalogue details

Licence: Public Domain Mark

Credit: Diseases of bees / Ministry of Agriculture and Fisheries. Source: Wellcome Collection.

    14/36 page 10
    Chilling may also occur if there is a serious loss of bees caused by disease, or by poisoning (see p. 23), when the remaining bees may be too few to cover the brood. A similar lack of balance between the amount of brood and the number of bees may occur if a prolonged spell of warm weather in the spring is followed by unseasonable weather later; the bees raise more brood than they can cover adequately in the event of a sudden cold period, the arrival of which causes them to contract and leave some of the cells unprotected. Young coiled larvae which have been chilled often turn a glistening black. and are difficult to see unless the brood combs are new; in old combs their colour matches that of the dark interior of the cells. Older chilled larvae become greyish in colour. The sealed brood may show moist, sunken and perforated cappings, as in American Foul Brood, but the cell contents are never ropy. The trouble will usually be cleared up by the bees themselves, but in severe cases the affected combs should be replaced by clean ones, and either rendered down for wax or kept in a dry place for use again later when the dead brood has become shrivelled and easy for the bees to remove. STARVED BROOD Colonies which have produced a large amount of brood in the spring may find themselves short of food during bad weather in the early summer. Some of the brood may then have to be abandoned: egg laying ceases, young larvae are often eaten by the bees and pupae may be found thrown out on the ground in front of the hive. Starved or neglected brood may also result from such operations as artificial swarming and certain systems of swarm control, if they are carried out thoughtlessly. It should be realized that in our variable climate bees sometimes run short of stores in May or early June, or even later, and a supply of sugar should be kept available for feeding in such an emergency. NEGLECTED DRONE BROOD The presence of a drone-laying queen or of laying workers leads to the production of irregular patches of drone brood. If the colony is weak, many of the larvae and pupae reared in worker cells are small and undernourished. If this state of affairs is allowed to continue, the brood becomes neglected by the bees and chilling causes death and subsequent decomposition. The combs have an untidy appearance due to scattered groups of cells with raised and irregularly dome-shaped cappings; many of the latter may be partially torn away, leaving the heads of the dead drones exposed to view. ' The decomposing larvae become soft and often brown in colour, and eventually they dry up to form dark masses sticking to the sides of the cells. The obvious remedy is to requeen or to unite the remaining bees with another colony, but the inexperienced bee-keeper may overlook the real cause of the trouble—the lack of a good fertile queen—and recognize only the more obvious decomposition of the brood, with its superficial resemblance to Foul Brood. Badly distorted combs and those containing a large amount of dead brood are best replaced by clean drawn comb. Io
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