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Autumn Nosema Testing - yes folks it's that time of year again

posted Oct 2, 2018, 2:54 PM by Helen Mooney   [ updated Oct 2, 2018, 3:20 PM ]
Nosema apis and Nosema ceranae are endemic in colonies here and should be strongly considered as a contributing factor if colonies are lost in late Spring.  Nosema is a silent killer.  Dysentery is only present towards the end stages of an infection of Nosema apis and not seen at all in the case of N. ceranae. So the visible signs can not be relied on. 

Mary Coffey in Teagasc HQ, is the key person to contact if you suspect and infection and in any case, 30 adult flying bees should be sent to her twice a year for testing, which is now free. Complementary to that, most clubs have one or two microscopes and invariably one or two members know how to test for Nosema.

Whilst time consuming, it is critical that we know the extent of Nosema levels, particularly in our breeding apiary. So these colonies are always the first to be tested, and testing is done biannually.  Colonies highlighted for rearing grafts next year must be Nosema free because this microsporidian prevents adult bees from digesting protein in the form of pollen.  If adult bees are sick due to Nosema, and cannot absorb protein, they, in turn, can not make brood food, and as a result, cannot nurse and feed young queens with the copious amounts of royal jelly required to rear superior queens.

Parallel to that, we must ensure that breeder queen colonies are also free of Nosema, which has a genetic component with regard to susceptibility levels.  This is one trait that we do not want passed onto the next generation. 

The third factor in limiting the extent of Nosema, and, which has been bourne out as an effective preventative measure in this apiary, is good hygiene between hive inspections: we rinse the hive tools and our gloves in 10% washing soda between each and every colony inspection.  In addition, we provide half a complement of fresh new frames each year and change hive floors or other hive parts if they begin to look dirty or mouldy. 

There is no licensed treatment for Nosema in Ireland, and we do not believe there needs to be, if good hygiene between inspections is adhered to.  Why add chemicals to a hive if it can be avoided? Here (https://photos.app.goo.gl/RiEpsjwkqszbXMLg6) you will find some more photographs of Nosema spores found in a few colonies today, as well as some photos of the preparation of a sample of 30 bees for testing. Thankfully many of today's smaples had negligible levels and two colonies were completely free of spores.  If you would like to know more about how to test for Nosema, please get in touch.