Tuesday 23rd of May 2017

THRESHOLD YARDSTICK


The following are methods to monitor mite levels and disease resistance. Note that threshold levels may vary by geographic location. Check with your local Bee Association or Research Lab for specific information for your area.
 

VARROA MITE

Testing Method:
 

Alcohol Wash Assay - (AWA)

Reference: ABJ Aug 2000 Pg. 659 Erickson

Below 5% - Resistant (w/o treatment)
Above 5% - Treatment required in late summer
Reference: ABJ Jan 2008 Pg. 51 R.Danka;J Harris;K Ward; R Ward

Varroa mite levels reach their peak in the fall of the year.
 

TRACHEAL MITE

Testing Method:

Professional Laboratory Analysis
Below 20% - Resistant (w/o treatment)

Above 20% - Treatment required

Tracheal mite levels reach their peak in the winter and spring of the year.

HYGIENIC BEHAVIOR

Testing Method:

1. Pin Prick (24 Hours)
Reference: Apidologie 30: (1999) Pg 367-374 Gramacho K, et al.

2. Freeze/Kill Brood Assay (48 Hours)
Reference: Bee Culture May 1998 pg 23 Spivak

Above 90% removal of dead brood = Hygienic Behavior

Hygienic Behavior standards can be further improved in a selected population by decreasing the standard removal time from 48 hours to 24 hours, with a minimum of 95% of the dead brood removed. This is the standard maintained by OWA
 
NOSEMA

Testing Method:

Professional Laboratory Analysis
Reference:: Bee Culture Nov 1999 Pg 34 Bach

Below: 4,000 spores/bee -- Not detectable

Above : 1,000,000 spores/bee - Treatment required

Nosema levels reach their peak in the spring of the year.