Beef IQ: Biology and Management of Horn Flies and Face Flies Kelly Loftin Associate Professor/Extension Entomologist Department of Entomology Fayetteville, Arkansas 479 575-3462
[email protected]
Livestock Pests - Flies “Pasture”
breeding flies
– Horn Fly – Face Fly “Premise”
breeding flies
– House Fly – Stable Fly Black
flies or Buffalo Gnats Biting Midges Horse Flies
Family Muscidae Horn Fly Haematobia irritans
Horn Fly – Economic Importance Most economically important insect pest of pastured cattle in the U.S. Losses occur through blood loss and annoyance, infestations of up to 10,000 flies per animal have been documented. Losses in cow-calf production is an indirect reduction in calf weaning weight. Reduction in calf weaning weights vary from 18 pounds and up. Stocker cattle gains may be reduced by 50 pounds. Linked to increased summer mastitis in cattle
Horn Fly - Life Cycle & Biology Haematobia irritans Complete metamorphosis Adult remains on host - except for egg laying.
Horn Fly - Life Cycle & Biology Adults live from 6 - 8 weeks, mating occurs on the host about 3 days after emergence. Eggs laid on fresh cattle manure, less than 10 minutes old Larvae develop in manure. Horn flies overwinter as pupae in the soil. Life cycle from egg to adult is from 9 - 12 days.
Two Seasonal Peaks in Abundance 350 300 250 200 150 100 50 0 March
April
May
June
July
August Sept.
Oct.
Nov.
Horn Fly Management Return of $ 2-5, for each $ 1 spent. Treat when population reach an average of 200 per animal for beef cattle (100 for dairy cattle). Dust bags, back rubbers, mechanical traps. Mineral/feed additives (IGR’s –methoprene, diflubenzuron; Larvicides - tetrachlorvinphos). Sprays, pour-ons, dusts. Insecticide impregnated ear tags.
Economic Thresholds and Counting Horn Flies Economic injury level is 150-200 flies per animal (75-100 dairy). Count flies on a minimum of 10 animals to obtain an average. Whole body, one side, two sides? Whole animal counts are more accurate but not always possible. When flies are less than 25 per animal count individually, when greater than 25 count in multiples of 5, 10, etc.
b
a Drawings of estimated population of horn flies on cattle; a = 50, b = 100 and c = 200.
c
Horn flies on bull and belly of Hereford.
Control Methods
Horn fly (Bruce) trap Passive, no chemicals Restrict access to feed or water Animal must pass through trap Up to 70% control Cost (material): $500-550
Potential Issues with Trap Trap
maintenance (horned cattle) Alternate water sources (rainfall and wet weather water sources) On occasion individual animals will not pass through trap
Horn Fly Demonstration – Dallas County 250 Treatment threshold 200 per animal
Average horn flies per animal
200
150
Trap Control 100
50 Cattle moved to another pasture
Date
4 00 23 /2 9/
9/
16 /2
00
4
04 9/ 20
04 9/
8/
9/
2/ 20
4 26 /2
00
4 00 19 /2 8/
8/
12 /2
00
4
04 8/
5/ 20
4 00 29 /2 7/
7/
22 /2
00
4
0
Insecticide Impregnated Ear Tags One treatment ? If not applied too early Organophosphates, pyrethroids, organochlorines and now macrocyclic lactone (abamectin) Insecticide resistance should be considered Insecticide classes should be rotated
Horn Fly Demonstration – Stone County 400
350
Average horn flies per animal
300
250 Treatment threshold 200 per animal Control Ear Tag*
200
Backrubber** *One Avenger ear tag per animal. **Backrubber charged with permethrin and diesel
150
100
50
0 8/21/2006
8/28/2006
9/4/2006
9/11/2006
9/18/2006
Date
9/25/2006
10/2/2006
10/9/2006
Ear tag Insecticide classes Insecticide Class
Beef Dairy*
Synthetic Pyrethroid
Yes
Yes
Organochlorine**
Yes
No
Organophosphate
Yes
No
Macrocyclic lactones
Yes
Yes
* Lactating dairy cattle. ** Existing stock only (Avenger), no longer manufactured.
Remember to rotate insecticide classes and remove tags when they become ineffective or at the end of the fly season to lessen insecticide resistance or tolerance issues.
Backrubbers and Dust Bags Self treatment device Recharge when needed Backrubber is saturated with a light oil solution containing insecticide Dust bags are closed mesh burlap bags containing insecticide dust – no mixing necessary Best if forced use
Paired, forced-use dust bags
Forced-use backrubber
Issues with Backrubbers and Dust Bags Are
the animals using the self-treatment device? Forced-use deployment is best (restrict access to feeders, etc.) Maintenance and charging
IGR’s and Larvicides Insecticide mixed into trace minerals formulated as a block, as granular form mixed with feed, or as liquid feed Consider proximity to untreated animals Kills horn fly larva developing in manure Animals must eat a specified amount each day Examples: IGR’s - Altosid (methoprene) and ClariFly (diflubenzuron). Larvicides – Rabon (tetrachlorvinphos)
A small amount of insecticide is poured down the backline Rates vary ~ about ½ ounce maximum Higher insecticide concentration than sprays (310%) Two types: traditional insecticide and endectocide Endectocide pour-ons control internal parasites, lice and horn flies, consider horn fly control as an added benefit
Pour-ons
Endectocides for horn fly control? Ivomec, Cydectin, etc. Pour-ons Cost of endectocide pour-ons are decreasing especially with generics. Probably best not to rely on endectocides alone to control horn flies (use when necessary for internal (worms) parasites). Label excerpt …should be a part of the parasite control program for both internal and external parasites. Ivomec pour-on will control horn flies from 1428 days, meaning multiple applications may be required during a fly season.
Sprays
Controls adult flies, ticks, lice High pressure sprays to apply a large volume of insecticide solution (1-2 quarts) Low-volume sprays apply about 2 ounces per animal, uses nozzles set up in gate or doorway where animal must pass
Walk through sprayer Restrict access to minerals or water Animals are automatically treated as they pass through (electronic eye) Not to be continuously operated – operate only when fly numbers reach treatment threshold Commercial units are available
Solar powered automatic sprayer
Horn fly demonstration – Washington County 700
600
400 Treatment threshold 200 per animal
Automatic sprayer* Control
300 *Charged with permethrin (2 oz. Permethrin-10 per gallon water) 200
100
Date
10/18/2006
10/11/2006
10/4/2006
9/27/2006
9/20/2006
9/13/2006
9/6/2006
8/30/2006
8/23/2006
8/16/2006
8/9/2006
8/2/2006
7/26/2006
7/19/2006
0
7/12/2006
Average horn flies per animal
500
Issues with automatic sprayer Are the animals using the sprayer? Similar issues with back rubbers, dust bags and trap. Restrict access to minerals or water (forced use). Individual animals may not use the sprayer (observe). Cattle should be acclimated to sprayer. Inert ingredients (xylene) in some insecticide formulations will damage pump. Most animal insecticides work fine (exception: Ravap, but formulation may be changed to remove xylene).
http://www.uaex.edu/Other_Areas/publications/PDF/FSA-7031.pdf
Consult MP 144 “Insecticide Recommendations for Arkansas” which is updated yearly. http://www.uaex.edu/Other_Areas/publications/HTML/MP-144.asp Read and follow the insecticide label.
Family Muscidae Face Fly Musca autumnalis
Face Fly – Economic Importance Musca autumnalis Introduced into North America in 1952, native to Europe, China, North Africa, etc. Economic losses from decreased weight gain, decreased milk production, and mechanical transmission of pinkeye Does not reach pest status every year in Arkansas, usually only a major problem 1 or 2 years out of every 5 years. More of a pest in north Arkansas than south Arkansas
Face flies on cow (left) and calf infected with pinkeye (right).
Face Fly
Face Fly Biology Intermittent feeders Females feed on secretions around the eyes and on saliva (ptotein for egg production) Female and Male feed on nectar and pollen Once feeding is complete the female leaves the host
Adult female lays eggs on fresh cattle manure Eggs hatch into larvae Larvae develop in the manure Larvae pupate in soil near manure pat Adults emerge from pupae (white) Life cycle from egg to adult is from 11 - 17 days Overwinter as adults
Face Fly Life Cycle
Face Fly Management Face fly are difficult to control because they are found on the face (hard to treat area) and spend little time on the host. Insecticide treatment may be necessary when an average of 10 flies per animal (face) are present. Face flies are equally attracted to adult cattle and calves. Self treatment devices (back and face rubbers, dust bags, face misters) provide control. Insecticide impregnated ear tags provide limited control (pyrethroid ear tags (2 per animal) are generally more effective for face flies than the organophosphates).
Consult MP 144 “Insecticide Recommendations for Arkansas” which is updated yearly. http://www.uaex.edu/Other_Areas/publications/HTML/MP-144.asp Read and follow the insecticide label.
