Rumor: Is Fumagillin believed partly responsible for late winter colony die-offs

[fatscher]

Up here in Northern Virginia (or down here, depending on your perspective) some of our expert regional beekeepers are saying an adamant NO!!!! to feeding bees syrup with fumagillin added to counter Nosema.

This is the same bunch of experts who were believers in fumagillin 6 months ago.

I'm not clear why but, I understand they believe Fumagillin may be harming the bee's resistance to this cold weather.

Has anyone heard this before? I know I know, there are the good people who don't believe in any sort of medication. But I'm curious if the medicine-believers have heard anything on this.

[sqkcrk]

I don't know about that, but I have heard that Fumadil-b is not effective against Nosema cerana, as it is against Nosema apis. So maybe that's what is going on.

I also heard that in Spain(?) double strength Fumadil-b treatments have been used to try to "control" Nosema cerana.

This is one of the problems w/ Nosema. Beltsville won't test samples to determine if the samples are Nosema apis or Nosema cerana. It's too expensive and time consuming. I think that it takes a DNA test to be sure.

[oldenglish]

I will try to find the article and post it but I read somewhere recently that fumigillan in mammals weakens the immune system, although not sure about bees, if it does I would think the worst time you could give it would be in the fall going into winter and in the spring when you want a strong build up

Found it,

From BeeResearch – Nosema update
This issue of colonies stronger if fed protein without fumagillin, only use
if needed - could be explained by one of the first comments to me by Dr.
Robert Cramer at MSU.
He's a fungal pathologist in the molecular veterinary labs in Bozeman, has been working on alternatives to fumagillin - see Jan Bee Culture.

Robb was surprised that beekeepers used fumagillin. He said that in mammals, fumagillin is known to suppress the immune system, not something one
Wants to see when treating sick animals. He didn't know if this applied to bees-I suggest that he not waste time confirming this, but to immediately focus on alternatives for Nosema control, which he did.

[Ian]

It helps winter our bees up here,
reduces the incidence of nosema, helping the bees winter better,
we winter in cold winter climates,

This is what our researchers are telling us,

Id call that rumour

[tecumseh]

considering the KNOWN cost of the item and the POSSIBLE benefit plus the QUESTIONABLE downside ECONOMIC impact of not using this compound it is quite understandable why some might not want to use the product.

Here the effect of not using the product 'if you are a honey producer' barely registers and is likely of minor economic impact... whereas in places northward the economic impact can be significant (and possible more importantly immediately recognizable).

everytime I buy a bottle of the stuff I can not help but believe that some large commercial concern is fairly routinely gaffing beekeeper via the price. I suspect ANY alternative product would make the price of the product quickly collapse.

[beemandan]

Here the effect of not using the product 'if you are a honey producer' barely registers and is likely of minor economic impact... I'm not so sure that applies to Nosema ceranae. Its my understanding that n ceranae isn't associated with long periods of confinement as is the case of Nosema apis.

[tecumseh]

I ain't certain either Dan. It is quite evident to me that most northern tier bee keepers have much more experience recogning and dealing with nozema apis than us southern beekeepers simply because it is so evident for those beekeepers that endure long winters.

old studies of packages and established hives moved north from southern location can be highly infected without showing any signs beyond being called 'poor doers'. some of these old studies suggest that infestation level can be remarkable high without any OBVIOUS signs.

It was also my understanding (any yes or no information to this notion is greatly appreciated) that nozema carena has mutated in the process of getting from there to here.

It is remarkable how very long the US of A kept these pathogens out until we decided that trade with china and the interest of packers was more important than the PRODUCERS here .

[winevines]

I will try to find the article and post it but I read somewhere recently that fumigillan in mammals weakens the immune system, although not sure about bees, if it does I would think the worst time you could give it would be in the fall going into winter and in the spring when you want a strong build up

Found it,

From BeeResearch – Nosema update
This issue of colonies stronger if fed protein without fumagillin, only use
if needed - could be explained by one of the first comments to me by Dr.
Robert Cramer at MSU.
He's a fungal pathologist in the molecular veterinary labs in Bozeman, has been working on alternatives to fumagillin - see Jan Bee Culture.

Robb was surprised that beekeepers used fumagillin. He said that in mammals, fumagillin is known to suppress the immune system, not something one
Wants to see when treating sick animals. He didn't know if this applied to bees-I suggest that he not waste time confirming this, but to immediately focus on alternatives for Nosema control, which he did.

Someone offered this explanation that they heard at the Reno conference for why using fumagillan is not good. Any comments or verification?

The information on Fumigillin I got at ABF in Reno this January. It was the subject of several lectures. Now I have to get the information from them on how to exactly count Nosema spores. Some people do an exact count using a hemocytometer and the other was just using a regular slide and cover slip doing an estimate. The last method can be done right in the field if necessary. What has been discovered is that when we use Fumigillin we are eliminating that species (Nosema apis) which is susceptible. We then leave behind Nosema cereana which is resistant. Nosema apis is a problem in the winter months and the problem is more readily visible with bee poop on the outside as well as all over the inside of the hive. Nosema cereana is active all year round and can cause a colony to collapse at anytime as well a queens to fail regularly. Now we are getting a picture! If has been discovered that when a colony is fed protein (brand is not a factor), it helps that colony to cope with the Nosema c. infection, and in some cases, it can no longer be detected. Back to proper diet for bees as well as people. And, yes, we want FAT BEES!

[Allen Dick]

I agree. Good forage and supplementary feeding are keys to success, as is avoiding drastic and unnecessary manipulations, Some manipulations, like splitting and requeening and minor loosening of the cluster by inserting the occasional empty frame or foundation frame at the right time are actually beneficial. Most others are not.

Moving bees is hard on them, especially if not done with forethought. One move can actually be beneficial, but further moves over a short timespan (a month or three) can be detrimental unless the move is to superior pasture.

I gave a way three large jars of fumagillan when I retired. I had no use for it. Whenever I checked my bees, I could not find any spores, and I do know what I am doing, since we ran a small lab doing testing for other beekeepers.

In my view, good beekeeping is the best preventative and cure for nosema, but I am sure that everyone's situation is different, and sometimes things happen.

Nonetheless, it is always a good rule to feed your bees, put them on good, varied pasture, and avoid stressing them with excessively invasive inspections and manipulations.

[alpha6]

Last May at the Colorado Beekeeping Assoc. meeting, Dr. Frank Etschen gave a presentation on tests that were done with bees and nosema where they fed bees using different concentrations of Fum B and others with just Sugar water alone. The test was funded by Fum B producers. Though he would not come out and say it (because of who funded the study I am sure) the results as shown on his slides showed no difference and in some cases a less of an effect on nosema those who received Fum B than those who received S/W. So from his study it can be determined that just feeding S/W to bees infected with nosema has the same effect (or gets the same or better results) as feeding with Fum B.

I wish I had a copy of the study to link to but I can't find it on the web. If I do find it I will link it. Anyone else get this same presentation?

[Cedar Hill]

Regardless. My bees seem much healthier using it. Whatever works for them up here in MA. I'll use.

[Ian]

>>What has been discovered is that when we use Fumigillin we are eliminating that species (Nosema apis) which is susceptible. We then leave behind Nosema cereana which is resistant.

Isnt this interesting. Thanks for the input. It makes a lot of sense, you know. How else is nosema c out competing nosema a? I am going to pass this past my provincial apiarist.