Avoid Footrot Like
This article first appeared in The Working Border Collie, Inc. in July/Aug 1993.
by Mike Neary
Extension Sheep Specialist
|Footrot in the ewe flock is a frustrating
situation. anyone who has fought footrot can attest to this. Seldom is the battle
completely won. Footrot always seems to win a partial victory. Whether through decreased
production, increased labor and medication costs, decreased ewe longevity and higher
culling rates. Footrot can be a wicked health problem in sheep or can be a mild annoyance.
The only good thing I can think of about footrot is that it can give the dogs a lot of chute work through the footbath and some gathering and shedding work.
**Prevention of footrot is the only practical way of dealing with this problem. Avoid footrot like the plague.
Causes of Footrot
Footrot is caused by a synergistic action of two anaerobic bacteria, along with environmental conditions conducive to their growth and spread. The bacteria are; Fusobacterium necrophorum and Bacterioides nodusus. The bacteria F. Necrophorum is commonly present in soil, manure, etc. It is the B. Nodusus organism, when present, that causes the problem. Again, both bacteria have to be present to cause footrot. There are over 20 strains of the B. Nodusus bacteria, varying in their infectivity and severity.
Warmth, mud and poor sanitation are environmental conditions that also favor footrot spread. these conditions create the anaerobic (lack of oxygen) conditions necessary for the spread of the disease. The B. Nodusus organism will only live in soil for 14 to 21 days.
At the risk of being annoying, I want to repeat the statement, avoid footrot at all costs. If nothing but this point is remembered, this article will have been successful.
There are mountains of misinformation that are spread about footrot. Remember this also; footrot is spread by sheep carrying the disease. Certainly, footrot can be spread through equipment and contaminated premises. However, the overwhelming cause of footrot in clean flocks is through introduction of sheep carrying the disease. Most people that get footrot in their flock, buy it. Not a good bargain.
Footrot bacteria can live in cracks and crevices of a sheep's hoof for months. Often, they will not even limp until environmental conditions are right to activate a case of footrot.
Buy sheep from a flock that is free of footrot. Isolate all new purchases fro at least 30 days. Buy sheep from honest breeders that will honestly tell you their health problems or otherwise. Be incredibly cautious about buying "bargain" sheep at the salebarn, etc. A free sheep with footrot will be an incredibly expensive individual.
For those fighting footrot, the goal is to dry out the infected feet and introduce oxygen. This is accomplished using chemical drying agents and close trimming of infected feet.
Some of the chemicals used are: Zinc sulfate, copper sulfate and formaldehyde. These chemicals are usually used in a footbath or soaking area. Zinc sulfate is usually the best, safest compound for man and beast. Antibiotics can also be used to help cure footrot. When available, the footrot vaccine can also be helpful in the footrot fight.
Keeping feet trimmed of overgrown tissue will reduce mud and manure packing and decrease the chances an anaerobic environment will develop. Sheep that have footrot should be trimmed ruthlessly. Do not be frightened of a bit of blood.
It is important to separate infected sheep into their own hospital group and away from those not infected. This allows you to concentrate your efforts on the infected sheep and helps prevent further spread of the disease. Since footrot lives in soil for only two to three weeks, use planned pasture rotating to you advantage.
Some breeds, lines or individual sheep seem to have a propensity for susceptibility to footrot. if you have some sheep that cannot be cured, culling may be the best strategy. If you have a small flock of grade sheep, it may be more feasible to sell the whole flock and buy more sheep in two to three weeks.
Do not believe the old wives' tales about footrot. Footrot is most commonly spread by infected sheep entering an uninfected flock. Do not buy footrot! Prevention is the best cure.