[Jacob-list] safeguard and anthelmentics

[Jacobflock at aol.com]

In a message dated 10/16/03 5:59:36 PM Central Daylight Time, 
patchworkfibers at alltel.net writes:

<< We had a problem with Safeguard resistance a few years back and haven't 
used it 
 until this year when it has worked fine.  An interesting note is that a vet 
told me 
 that your/my parasite population, assuming that our sheep are kept to 
themselves, is 
 it's own tiny environment.  It may  not matter what wormers don't work for 
the guy 
 down the road if you aren't sharing grazing land. Overworming in an 
individual flock 
 can create resistance that you may not see in a flock that worms twice a 
year. Kinda 
 over simplified, I know.  
 
 Having a fecal exam done by a vet is inexpensive and you don't even have to 
have the 
 vet actually see your sheep.  You can transport that tiny little bag of 
fresh 
 droppings quite easily.  It's not like OCD where you need either an X-ray or 
a 
 decapitation to diagnose. 
 
 A sheep may have just been wormed, but still be wormy.  And a sheep may look 
 "poorly" and have diarrhea and not be wormy.  
 
 Linda >>

Parasite resistance to anthelmentics is and will be the problem of the next 
decade.  There are NO new products on the horizon.  If parasite resistance to 
current applications continues at what appears to be a rapidly increasing rate, 
the genetic resistance of the sheep host will be the last best defence.  

A fecal test is cheap in the larger scheme..  Under using "wormers" is a very 
bad practice ... over using "wormers" can be just as bad.  Some breeders are 
"stressing" sheep for parasite resistance ... the sheep can carry and handle a 
load but show no signs of wasting.  Some breeders use "wormers" four to six 
times a year on a "schedule".  One Jacob breeder had no evidence of worms in 
his flock ... and so he never wormed.  I am aware of another flock that worms 
some sheep once a year. The use of anthelmentics is best done as sheep/flock 
specific.

Fred Horak