i have mentioned in several posts that i was convinced that bees feeding on real honey would have a much better chance of staying healthy as compared to those feeding on syrup.
my thinking was that they would be getting the vital nutrients in real honey (not present in syrup) that are necessary for their immune systems to function optimally.
now i'm not so sure about that.
after revisiting randy oliver's papers on bee nutrition, i have come to understand that those vital nutrients for longevity and immunity come primarily from pollen.
oliver does a better job than i ever could explaining what vitellogenin is and the role it plays in bee health and wintering longevity:
http://scientificbeekeeping.com/fat-bees-part-1/ (this is part one of a four part series)
i believe i have found a likely explanation as to why i had 5 of 18 hives suffer queen failure over this past winter. it may be that the natural forage that was available here late last year didn't have quite enough nutritional quality.
this may explain why those who supplement with protein patties in the fall are having better wintering success.
this brings me to think like it's not bad to 'top off' or 'bring up to wintering weight' using syrup late in the year, fearing that the bees will have less immunity to pathogens if they are using some stored syrup for fuel.
i have been putting a little dry pollen substitute out in the late winter for the bees to add to the natural pollen that they bring in. it may be a good idea for me to put some of that out in late summer as well to augment the natural flow as they get into rearing those last rounds of bees for overwintering.