Sludge Watch ==> Co-locating sewage sludge compost and mega dairy barns - FLY ALERT

[maureen.reilly at sympatico.ca]

Sludgewatch Admin:

I see that where sewage sludge compost sites are going in, cow condos move 
in next door.
I figure the two stinky groundwater polluting industries can blame 
environmental damage and odors on each other indefinity.

But the flies ... especially the sludge flies  (see testimony about Nursery 
Products, Calif)...can be a problem.
...........................................



Flight risk: Flies a health concern for beef cattle

June 6, 2006
AgAnswers
Purdue Extension
http://www.aganswers.net

What's the buzz around cattle pastures these days? The same that it always 
is when the weather turns warm: flies. The winged intruders are more than 
just an annoyance to grazing cattle.
Flies also can transmit diseases and stunt growth, said Ron Lemenager, 
Purdue University Extension beef specialist. Producers can protect their 
herds through proper sanitation and insecticides, he said. "For grazing 
cattle we're really concerned about two different types of flies: face flies 
and horn flies," Lemenager said. "Face flies tend to feed on secretions 
around the eyes and noses of cattle. They move from one animal to the next. 
The face fly is a major vector for M. bovis, which is a bacteria that can 
cause pinkeye.

"The horn fly is a little different. That particular fly is much smaller in 
size and tends to stay with the same animal, leaving that animal only to 
deposit eggs in fresh manure patties and then returning to that animal. The 
horn fly is a bloodsucker and tends to feed on the back, withers, neck and 
sides of animals. The horn fly can cause reduced weight gains." Face flies 
are similar in size to common houseflies. They feed without piercing the 
cow's skin. In addition to carrying the bacteria that causes pinkeye, face 
flies also can transmit eyeworm and infectious abortion. Horn flies are 
about half as big as face flies but no less troublesome.

The flies inject their tube-like mouthparts into cattle and draw blood for 
food. Horn flies can feed as often as 30 times per day. The feeding causes 
stress for animals, often leading to weight loss. Horn flies also can spread 
summer mastitis, a disease affecting a non-lactating cow's mammary glands.
"These flies start becoming a problem about late May," Lemenager said.

"By the middle of June producers should be thinking about fly control."

Control methods for face and horn flies on grazing cattle include 
insecticide treatments. Insecticides usually are applied directly to the 
animals, by various methods:
Insecticide-impregnated ear tags -- Insecticide is gradually released from 
the tag through the animal's body oils. Cows spread the chemical when they 
groom themselves or their calves.Dust bags -- Insecticide powders are 
sprinkled over cattle as they walk under the bags hanging above gateways. 
Bags that contain oil- based insecticides are known as oilers.Pour-ons -- 
Concentrated insecticide is poured along the animal's top line.Sprays -- 
Insecticides are sprayed onto cattle. Some sprays come in ready-to-use 
forms, while others require dilution with water.

Feed-throughs -- Cattle consume supplements or feed mixes containing a 
larvacide. The compound disrupts the life cycle of developing flies after 
the eggs are layed in fresh manure.

Horn flies are vulnerable to most control methods, Lemenager said. "The horn 
fly is very easy to control because it stays with the animal," he said. "Fly 
sprays, insecticide-impregnated ear tags, back rubs with insecticide and 
dust bags are pretty effective methods of control. "We also can use 
feed-throughs, in which you've got insecticide that's part of a mineral or 
supplements that you might purchase commercially. The feed-through 
insecticide passes through the animal into the manure, and then it breaks 
the life cycle of the fly before it can become an adult. It works primarily 
on the pupa stage of larval development." Producers have fewer control 
options for face flies. "The face fly is a different critter," Lemenager 
said. "The feed-through insecticides don't work quite as well if you have 
neighbors who are not controlling their flies, because these flies will 
migrate from animal to animal. So you're probably stuck with using 
insecticide sprays, impregnated ear tags, dust bags, oilers or some 
combination of them." Producers should be careful which insecticides they 
use and how they use them, Lemenager said.

"There are some resistance issues with some of these insecticides," he said. 
"Producers should visit with their local herd health provider or Extension 
educator about what's working in their area. We're probably going to have to 
switch the insecticides we use from one year to the next, so that we don't 
develop a significant resistance problem." Additional information about 
flies is available in Purdue Extension publications E-12-W, "Control of 
Cattle Pests" and E-206-W, "The Face Fly," both written by Ralph Williams, 
Extension entomologist. The publications are available online at Purdue's 
Beef Extension Publications Web page, at 
http://www.ansc.purdue.edu/beef/beefpub.htm .