Several local sheepfarmers have lost lambs and sheep to flystrike this past week. We've had an incredible amount of rain which doesn't help. Aside from having sheep sheared in spring, which they and myself do, is there anything else to help prevent this? I don't want any more disasters and its a horrible way for an animal to go. For those of you who have no idea what fly strike is, flys attach themselves to an animal in large groups, apparently anywhere on the body, lay eggs unde the skin , which develop into maggots and eventually kill the animal via the toxins produced.Thats all I know. Some of my old sheep disease books refer to blowfly which I assume is same thing, but that was books from Australia and England and 50 years ago. Thanks.

-- Kate Henderson (sheeplady@catskill.net), July 08, 2000

Answers

Dip them.

-- Hendo (redgate@echoweg.netm), July 08, 2000.

It is the same thing - sheep get flystruck or fly-blown (hence blow flies). Those who care about their sheep, learn about it - it can happen anytime, although the conditions you describe are when it's most likely. Those of a sensitive turn of stomach move on for a while. Kate, this is not aimed at you personally - lots of people who need to know the facts of life, and haven't got the start you have, read this forum.

Flies lay their eggs in moist warm conditions with ample available organic material to feed on. That can be manure, fresh meat, an open wound, but it's also quite likely to be warm wet wool, with the scurf, lanolin, dirt, faeces, etc beginning to decompose. Some flies can lay under the skin, but it's not necessary for sheep - the above is enough to get started. The maggots hatch, feed, excrete, the area stays damp, the skin starts breaking down, the maggots keep eating - the living animal now, but eventually no longer living once the maggots have eaten enough of it. Don't know about toxins, but the sheer removal of flesh would seem to be enough to account for death in my opinion. Doesn't stop the maggots of course - it's easier for them when the animal's rotting all through, rather than just on the surface.

Have I convinced you it's unpleasant yet? Good. If you keep sheep with wool, it can happen - be ready for it (as Kate is doing), you owe the animals that much. First of all, as a preventative, crutch or have crutched all sheep that need it (that is, clip wool and accumulated manure away from their backsides). Some sheep won't need it - they may be hair-sheep, or some are "naturally crutched" - they just grow that way. If you might have fly problems, have the lamb's tails docked (or use the rubber rings). Detail on this has been covered in a previous thread. It's way kinder than letting them be chomped to death slowly by hundreds of maggots. If you're so cruel or so irresponsible that you'd prefer to let your animals die in agony rather than you have the discomfort of thinking about using sensible management practices, then you shouldn't have the animals.

If pasture is particularly lush, perhaps move the sheep to drier pasture for a while - even move them onto the lush pasture and then off again after a couple of hours each day, to avoid them getting scours.

Talk to surrounding sheep graziers/farmers/whatever you call them, and see what they advise. They may also be able to show you fly- struck sheep - either before or after treatment, or ideally during. Also talk to your local produce store or whatever it is that has farmers' supplies around there. See if local/state agricultural extension agencies can advise, as well. As always, in everything, the more you know, the better. Practices can vary, too, from place to place and over time. What we use may not be legally acceptable for you - certainly while the way we do it hasn't changed, things we used when I was but a lad are illegal now - too toxic.

What we do here is to use hand shears, and a pour-on insecticide that's specially formulated for maggots (which react differently to grown insects). Catch the flystruck sheep, clip the maggot-infested wool very short until the base of the wool is exposed, and into clean dry wool surrounding the fly-blown area, then pour on the insecticide, and puddle it around and into the centre of the struck area with the flat side of the shears, working it into any areas and flesh that might conceal maggots. Check the animal for further strike in other areas while you've got it down, then release it.

Most common area for fly-strike is around the anus, where faeces (and urine on ewes) accumulate. Second most common is on the back, where soaked wool can stay wet for days in damp conditions - the longer the wool the worse the situation. Poll strike on the head, similar to the back, in woolly-headed sheep. Strike around horns, where wool doesn't dry as quickly. Strike on flanks, particularly if animals have then lain on their side or with their side against something for a while after eggs have been laid. Strike around the pizzle in wethers and rams. And elsewhere.

Go around your sheep regularly (daily is certainly enough, two- or three-daily would be sufficient if you had huge numbers - I'm talking hundreds or thousands here), watching for signs of fly-strike. Badly struck areas appear dark and damp, because of serum oozing from the non-skin. Sheep can appear to have an itch or irritated area - no doubt that's the case - may be trying to rub on something, or scratch with their hooves. Wool can appear to be coming away in strands - it is, as sheep scratch at it, and as its anchoring in flesh gives way. GET LOCAL ADVICE from experienced people - more than one source.

The price of freedom from fly strike is eternal vigilance.

-- Don Armstrong (darmst@yahoo.com.au), July 08, 2000.

Hendo is right up to a point - dipping can work, has a short-term residual effect, but you can't do it too often (accumulated toxicity, withholding periods), and it's expensive. Well worth considering if the situation is getting out of control otherwise, or if you would be dipping them soon anyway.

The dip, diluted, may be useable as the pour-on insecticide. GET ADVICE ON THIS - it's toxic stuff, and not all dips are suitable.

Kate's comment about spring shearing is excellent. Ideally you want to have short-wooled sheep coming into the warm part of the year, with the wool growing longer as the weather gets colder. You need to exercise judgement here, and have shelter or at least wind-breaks available for newly-shorn sheep. I've seen hundreds of newly-shorn sheep killed by a cold wet snap - not ours, but a neighbour's. Doesn't have to be freezing weather either - just cold and wet and windy. You need to fit shearing around spring lambing though, and consider the risks of temporarily separating sheep and lambs if you shear after lambing - not a problem with small flocks.

-- Don Armstrong (darmst@yahoo.com.au), July 08, 2000.

Okay, what do you dip them with and how? My very old sheep husbandry books from Australia show big portable tanks with wooden ramps in and out for the hundreds of sheep they run. I only have fifty. We shear sheep in March, just before lambs are due. Also I always do the tails. My vet told me that most of the best dips are no longer legal to use in this country, I believe Lindane was one. I do look over my sheep each morning for any problems. Usually I can tell when they start acting differently .

-- Kate Henderson (sheeplady@catskill.net), July 09, 2000.

Kate:

This is from the Handbook of Livestock Management Techniques:

Sheep do not like to enter water or a spray and must be forced to do so. Holding pens must be positioned both ahead of and behind the treatment area. Sheep will enter the dipping tank or spray area more readily if the approach chute is curved such that they cannot see ahead.

The dipping tank can be constructed of metal or concrete. It should be 12 feet long at the top and six feet long at the bottom, with a cleated incline for the other six feet. The tank should be two feet wide at the top, sloping to one foot at the bottom and it should be six feet high. The sheep should be completely immersed in the liquid (including their heads and ears).

Spraying can be done in a holding pen with a high-pressure sprayer equipped with a nozzle, or the sheep can be walked through a spraying device equipped with nozzles on each side as well as the top or bottom. In either case, the use of a pen is recommended to allow the treated sheep to drain briefly to save the liquid and prevent contamination of soil or pastures by the insecticide.

There is more to this. If you'll provide an address I'll make a copy of two pages and send them to you.

About twenty years ago I went on a business trip to New Zealand. Since I was assigned scheduling, I scheduled the trip for several days longer than I knew the meetings would take. Gave time for some day-trips. One was to a sheep farm and they happened to be dipping at the time. Rather a three-ring circus. As I recall two guys were above the tank with some type of push poles they used to completely immerse the sheep. The sheep had been sheared first.

-- Ken Scharabok (scharabo@aol.com), July 09, 2000.

For interest, Insecticides for flystrike is a state of Western Australia publication. Not necessarily directly applicable to your area, but similar information ought to be available for you. There should be similar ones on how to dip sheep, too.

Dipping is normally done soon after shearing because you want to treat the skin, but how much expensive dip you use is actually determined by the amount of wool there is to soak it up. A plunge dip is the old, simple way to do it (you literally dip the sheep in the chemical), but it takes a big hole, and it uses a lot of expensive dip solution - not economical for small numbers. A spray "dip" recirculates what isn't carried away in the wool, uses less chemical, is a little more complicated to build - basically more capital outlay, less running costs.

-- Don Armstrong (darmst@yahoo.com.au), July 09, 2000.

This is probably pretty obvious but everyone should realize that flystrike is not limited to sheep. We see several dogs and cats a year with it. Rabbits too. It is usually associated with areas that are badly soiled (feces, urine)or have sores (hot spots, wounds). A lot of long haired dogs that are outdoors and poorly groomed will develop the problem. The destruction of the flesh by the maggots causes the release of toxins that can put a healthy animal in a coma in 3 days. The maggots are hard to kill and i hesitate to use an insecticide on severely debilitated animals. Betadine works pretty well but the maggots have to be flushed out and/or picked off individually. Not a fun chore!!!! So if you have a dog with a thick matted coat get it shaved before problems develop. Also beware of soiling of the back end with diarrhea or a urine leakage problem. Good hygiene and daily attention can work wonders in preventing this in your pets.

-- teresa (teresam@ascent.net), July 09, 2000.

For a small herd, pouring on hydrogen peroxide draws them out quickly, then spray the affected area with tamed iodine.

-- Jean (schiszik@tbcnet.com), July 10, 2000.

Jean was correct with the peroxide--it will make the maggots come right out of the skin. When we dock lambs I usually go ahead and cut their tails off about 5 days after the bands are put on--and pour peroxide over the tail that is left just in case any fly problems are there--then spray well with iodine. As for a fly repellant, De-Lice was recommended to me by Pipestone. One ounce per 7 pounds for sheep. It is poured straight--right down the middle of their backs and repels flies like crazy. Use 4-5 cc per lamb. This will work for about 2-3 weeks. As we have had 3 mild winters in a row here in north Georgia we really have a fly problem this summer. Hope this helps.

-- Lynn N. Johnson (lynn@wauka.com), July 14, 2000.

dunno

-- mark cowan (johnstonthomas@hotmail.com), October 15, 2001.

Is DE (diatomaceous earth) not a possible help here?

-- Ann Markson (tngreenacres@hotmail.com), October 15, 2001.

Kate, excellent advice here! I would also contact Pipestone. pipestone.com Also if you can't dip the sheep, the high pressure washer is an excellent idea, and can be accomplished in a stock trailer. Vicki

-- Vicki McGaugh (vickilonesomedoe@hotmail.com), October 15, 2001.