During the 1960's, beekeepers in Louisiana and Texas complained about the fall and winter losses of bees in their apiaries (the so-called "disappearing disease" ). 

Oertel (1965) noted that the "disease" occurred in Louisiana from late September to early January when colony populations literally disappeared within a short time; only a "handful" of bees was left; honey stores were present; small amounts of pollen were sometimes present although pollen was generally absent; and brood rearing was almost nonexistent. He found that his checks for pesticide residues were negative and also observed that there were no samples of dead bees with which to conduct any analysis for (Nosema) disease. Williams and Kauffeld ( 1973) noted that the loss of bees in three commercial apiaries occurred during February which was later than the losses of bees during the 1960's. 

Since the loss of large numbers of colonies still recurs from time to time, we set up an apiary to observe the differences in colonies of bees with restricted and unrestricted broodrearing during fall and winter months in the Gulf Coast region. The effect of different food treatments on the population, amount of stored pollen and its relation to brood rearing, and consumption and storage of honey in the colonies from December to the end of March were also to be observed. It was hoped that the results would show the importance of continued broodrearing during the winter months in this region .  

The test was set up as a 2-3 factorial experiment in which the 24 colonies were randomly divided into two groups of 12 colonies each, one with the queens free, so they could lay eggs and brood rearing would be continuous throughout the test, and the second with the queens restricted. The queens were restricted with a wire screen push-in cage with one side made of queen excluder material so bees could enter the cage to feed and groom the queen . However , these queens in the second group could lay a maximum of only 25.8 cm2 (4 in.2) of eggs (brood ) . Thus, these colonies were forced into conditions that prevail in the north in October when egg laying and brood rearing most generally stop .  
  
Discussion 

The primary aim of the test was to determine how long honey bee colonies with populations of young bees could be maintained in Louisiana with almost daily foraging from October to March when brood rearing was restricted ( only about .12 dm2 of brood emerged every three weeks ). The October population of all colonies in both groups covered slightly more than 10 Hoffman frames of a Langstroth hive; the March populations of the two groups were very different. Colonies with uncaged queens had increased in population to cover an average of 14 frames ( continuous brood rearing and subsequent replacement of old dying bees by young bees ). Colonies with caged queens ( brood restricted ) had an average of only 2.2 frames of bees .. Two weeks after March 25, 50 per cent of these colonies were dead even though food supplies were present in  the hives . March conditions in these colonies were similar to those associated with disappearing disease in the southern states .

Overwintering of Colonies of Honey Bees with Restricted and Unrestricted Brood-rearing in Louisiana. 
Am Bee J, 115: 480- 490

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