Exam 2 Flashcards
What is colony collapse disorder
- First seen in 2006-07.
- Characterized by:
- Higher than normal winter losses (summer losses are now
considered). - Hives made of mostly younger bees.
- Small population of workers and drones.
- Plenty of food in the hive.
- Capped larvae are intact.
- Queen may still be present.
What is the varroa mite?
Varroa destretor
- External prasitic mite
- feeds on the **fat bodies **
- transmits a number of bee viruses
What tissue does the varroa mite feed on?
They feed on the liver of the fat bodys for bees.
The fat bodies liver/immune system.
A major intercation that casues CCD.
Which viruses are transmitted by the varroa mite?
Deformed wing virus
Black queen cells virus
Chronic bee paraysis virus
Acute bee paralysis
Name the Important key fetures about Deformed wing virus?
First identified in the 1980s in Japan.
* Iflaviridae in Picornavirales. *
* Positive sense RNA virus with a 10,000 kb genome encoding for a polyprotein.
** Transmitted by the varroa mite. **
* Circulative, non-propagative transmission.
* Causes deformed wings and extremities.
* Can also cause neurological symptoms,
including memory issues
What are the key features about Sacbrood virus?
Related to Deformed wing virus.
* Transmitted from bee to bee, not the varroa mite. * Infect larval bees, particularly the worker larvae.
* Infectious in dead larvae, pollen and honey for up to 1 month.
What are the key features about Black queen cell virus?
**Dicistroviridae, genus Cripavirus (order Picornavirales). **
* Positive sense RNA virus with a 8,550 bp genome.
* Asymptomatic in workers and drones.
* Kills queen bees.
What is the role of Fat bodies?
erves as storage for fat cells in bees.
* Important for overwintering.
* Responsible for production of royal jelly.
* Also important for biochemical reactions (functions as a liver!)
* Made of vitellogenin (a primary component of egg yolks).
* Winter bees have large deposits, summer bees have small deposits.
What Impact does deformed wing virus have on bees?
Causes deformed wings and extemities – Bee can not fly
Can also casue neurological symptoms, including memory issues —- Proble m bee has to rember how to get back home.
What is the most likely cause of colony collapse disorder?
The synergistic interaction between:
* Varroa mite feeding on fat bodies.
* Deformed wing virus disrupting fat bodies.
*** Both varroa mite and deformed wing virus down-regulating expression of immune system genes. **
What role does monitoring of varroa mite populations play in controlling CCD?
Monitoring of pest populations is an essential component of IPM management.
Three main methods:
1. Sticky trap
2. Jar method
3. Brood sampling
The threshold for action is low, but the threshold varies by country and sampling method.
What treatment options are available for CCD?
Chemical controls
Pyrethroids Organophosphates Formic acid Oxalic acid Thymol Powders (powdered sugar, talc, etc.) Mineral oils
Cultural controls
Heating the hive to 104˚F to cause the mites to drop off of the bees.
A wire mesh in the bottom of the hive can prevent varroa mites from climbing back onto the bees.
- Most effective when combined with stick traps.
Comb trapping- infested combs are removed from the hive.
What cultural controls are used?
Cultural controls
Heating the hive to 104˚F to cause the mites to drop off of the bees.
A wire mesh in the bottom of the hive can prevent varroa mites from climbing back onto the bees.
- Most effective when combined with stick traps. Comb trapping- infested combs are removed from the hive.
What genetic engineering options are being considered and developed?
RANi target Varroa mite genes
Use of Snodgrassela alvi (a bee endosymbiont) has been genetically engineered to induce RNAi against bee viruses and the varroa mite.
How do bee grooming habits impact CCD development?
Some Apis mellifera colonies are resistant to the varroa mite.
The mite is able to feed but cannot establish in the colonies.
The bees aggressively groom and remove the varroa mites.
The bees will also bite the mites to kill them.
This behavior is common in A. m. scutellata (East African lowland honey bee).
