what wormer as summer goes on?

[DB67]

Lambs got a white drench (ovispec) as a first worm in may. In the process of getting their second dose (cydectin). On the whole looking well. Bit dryer which alwyas helps!

Will perhaps look to dose again at end of july when we take some lambs off their mothers. They may not NEED it but id rather be safe than sorry and wait till mid august. Would using an orange dose be the most useful? Back to a white? Or are lambs old enough that any kind of dose would do the job?

Can nemo strike in july?

 

[exmoor dave]

probably not much point going back to white unless you know you have no resistance to it. nemo will be dropping away now.

orange (group 4) would be good if you are weaning.

 

[DB67]

Much appreciated.

 

[Poorbuthappy]

Tested some of mine this pm and found 400 epg of nemo and 100 of tricho.
Just watch the nemo as Cydectin isn't persistent against that

 

[Tim W]

DON'T use the orange drench unless you have proven resistance to other options, using drenches 'just in case' is not a sensible option and is exactly what helps accelerate resistance to anthelmintics

Do FEC's and then after treatment re test to check if the drench is effective ---know what works on your farm and what doesn't work before using a new series wormer---that way they will retain their effectiveness for longer on your sheep (and perhaps more importantly) on the national flock

 

[JD-Kid]

agree with tim in saying that the new brands being pushed a bit as being the only drench to use (spose to get a pay back on there R&D ) like the mectin's people went nut's with them was not long after they brought it out there was talk of restance happening

guys useing white for years and years i would say a good chance there is some restance unless people test there is no way of knowing

 

[DB67]

Are any drenches persistent against nemo?

 

[JohnGalway]

Get a sample of lambs FEC tested (We will take 10 individual dung samples - 15 lambs is the least amount to put in I have been told - each test to send to the lab). Use the same drench again (if it kills what you want it to kill). Then test the same lambs in either 7 or 14 days depending on drench. You'll know what your lambs had, what they have after the dose, and if the dose works, or if it didn't and you need to go in again with something different.

 

[Poorbuthappy]

Are any drenches persistent against nemo?

No.

 

[Devil's advocate]

It would be intersting with a closed flock on a mixed farm to try to clear the resistant worms out. Put all sheep on a reseed & drench with orange wormer, keeping moving them onto more clean grass. Plough out all the older grass for cereals. Then hopefully white drenches would work again?

 

[JohnGalway]

They reckon you should not dose 10% (I think it's 10%) of the lambs (best ones advised) to keep non resistant worms on the ground.

 

[Devil's advocate]

They reckon you should not dose 10% (I think it's 10%) of the lambs (best ones advised) to keep non resistant worms on the ground.

Yes but if going to clean ground (years of arable cropping) & then more clear ground surely the aim would be to kill all worms. I do know not practical for many, possible for me with a lot of expense & effort.

 

[Global ovine]

It would be intersting with a closed flock on a mixed farm to try to clear the resistant worms out. Put all sheep on a reseed & drench with orange wormer, keeping moving them onto more clean grass. Plough out all the older grass for cereals. Then hopefully white drenches would work again?

Once you (or previous owner of your flock) have challenged the worm populations in your sheep sufficiently (often enough or by under dosing) the surviving worms would have become the dominant worm strain on the farm. The problem is about 90% or more of the worm population is on the ground/pasture as eggs, stage 1,2 and 3 larvae. Therefore you would have to clear the farm completly of sheep for some years to restore the efficacy of a single chemical drench.
The fastest way to build up drench resistance in worms is to move freshly drenched sheep onto "clean" pastures. As all the new contamination going onto that clean area will then be eggs from those worms resistant to the chemical challenge. ALWAYS RETURN SHEEP BACK ONTO DIRTY AREAS SO RESISTANT WORMS BREED WITH SUSCEPTIBLE WORMS, THEREBY REDUCING THE PROGRESS OF SELECTION TOWARDS HIGHER RESISTANCE.

If you have any single chemicals still effective (eg whites or levamisole) you should cease using them now and only use that chemical in combination with another. IT IS IMPERATIVE TO MAINTAIN CHEMICAL FAMILY EFFICACY AT ALL COSTS. Once all your cheap options are gone you are left with 2 options, get out of sheep, or be forced to only use the new and very expensive options. NZ research has shown that by 9 drench challenges, worms are showing the first evidence of resistance! Long acting drenches are worse as the tail of the treatment allows those worms showing the development of resistance to slip through, thereby increasing the frequency of resistant genes in the worm population.

I strongly endorse the comments above by Tim W and John Galway.

 

[JohnGalway]

Yes but if going to clean ground (years of arable cropping) & then more clear ground surely the aim would be to kill all worms. I do know not practical for many, possible for me with a lot of expense & effort.

Keep lambs healthy and thriving by keeping worms susceptible to doses would be my aim. Can't comment on arable as I farm on a different planet lol. Is it even possible to eradicate worms? Can't see it being an option on an all sheep farm, but my knowledge is limited and I'll be the first to admit it.

Monday I will be sampling my lambs, early in the week is best for postal reasons, keep the sample fresh if the lab isn't near by. If I have enough Chanaverm (Yellow, levamisole) I will likely dose them with that. I used it earlier in the year as a cheapie against Nemo. If on my second test, which will be in 7 days time (the following Monday) as it's a Yellow drench, all is well, then Chanaverm will remain my drench of choice for lambs this Summer. I will try something else next year. A White drench or an Ivermectin drench would require a test interval of 14 days.

Previous to this I was a "dose just to be on the safe side" kinda guy, am attempting to mend my ways.


Oh yes, now I remember what I was going to say.......

To do a drench resistance test, which is what I'll be starting into on Monday, I need to leave a 6 week gap between when I last drenched the lambs. Not entirely sure of the reason, but it was stipulated for doing the test, I'd have liked to have tested two weeks ago but I held off.

 

[Poorbuthappy]

John I guess the reason they've told you to wait 6 weeks is to ensure sufficient worms are present to get an accurate test. Because of the way the fec is done, an egg count of 3-400 epg only involves counting 6 - 8 eggs on the slide (1 egg = 50 epg because of dilution technique) so obviously the more eggs present, the more accurate this becomes.

DA, we had triple resistance prior to moving farms. This was pre zolvix being available so we drenched sheep on moving with all 3 classes of drench. We used Cydectin, which was still working but had lost its persistency.

There had been sheep on the farm we bought just as winter keep from a neighbour, so I felt there should be some non resistant worms present to 'dilute' any resistant ones that made it through.

My vet had wanted me to buy some ewe lambs of known origin to import more non resistant worms, but with hindsight, we should have culled the flock and started fresh. That seemed drastic and too expensive at the time as cull values were much lower than currently.

Our first test the following summer suggested we'd left the problem behind, but by that autumn it was very apparent we hadn't.
This rambling discourse is basically to say it's not that easy to do away with the problem, and indeed I heard of a farm in Scotland that went out of sheep for several years to try to lose the problem, but within a few years of returning the problem was back.

 

[Devil's advocate]

Once you (or previous owner of your flock) have challenged the worm populations in your sheep sufficiently (often enough or by under dosing) the surviving worms would have become the dominant worm strain on the farm. The problem is about 90% or more of the worm population is on the ground/pasture as eggs, stage 1,2 and 3 larvae. Therefore you would have to clear the farm completly of sheep for some years to restore the efficacy of a single chemical drench.
The fastest way to build up drench resistance in worms is to move freshly drenched sheep onto "clean" pastures. As all the new contamination going onto that clean area will then be eggs from those worms resistant to the chemical challenge. ALWAYS RETURN SHEEP BACK ONTO DIRTY AREAS SO RESISTANT WORMS BREED WITH SUSCEPTIBLE WORMS, THEREBY REDUCING THE PROGRESS OF SELECTION TOWARDS HIGHER RESISTANCE.

If you have any single chemicals still effective (eg whites or levamisole) you should cease using them now and only use that chemical in combination with another. IT IS IMPERATIVE TO MAINTAIN CHEMICAL FAMILY EFFICACY AT ALL COSTS. Once all your cheap options are gone you are left with 2 options, get out of sheep, or be forced to only use the new and very expensive options. NZ research has shown that by 9 drench challenges, worms are showing the first evidence of resistance! Long acting drenches are worse as the tail of the treatment allows those worms showing the development of resistance to slip through, thereby increasing the frequency of resistant genes in the worm population.

I strongly endorse the comments above by Tim W and John Galway.

Thats a load of rubbish though isn't it.

Never used group 4 so should get a good kill, keep moving them on. I've only 30 acres out of 200 which has ever seen a sheep. Keep changing wormers move the flock on use the dirty grass for something else keep reseeding ploughing out grass for crops & keep moving on. Surely to let one animal be un wormed would be absolute vandalism.

 

[Poorbuthappy]

Not sure if your situation is a bit unique DA?
Are your saying those 30 acres are pp?
Or are they part of the arable rotation, so all your sheep grass is young leys?

The point about leaving some undrenched when moving into 'clean' grazing is that if you don't, every worm on that 'clean' pasture is a resistant one dropped by the newly drenched sheep. This is the fastest way to develop resistance.
I know - been there and got the T shirt.
10 years + ago I would have religiously drenched lambs before going into 'clean' grazing, whether that be new leys or aftergrass from silage ground.
I've now got triple resistance, and if I continued that policy with zolvix and startect would soon have resistance to them too.

We have to think about 'managing' the worm population rather than think we can eradicate it.

 

[Devil's advocate]

Not sure if your situation is a bit unique DA?
Are your saying those 30 acres are pp?
Or are they part of the arable rotation, so all your sheep grass is young leys?

The point about leaving some undrenched when moving into 'clean' grazing is that if you don't, every worm on that 'clean' pasture is a resistant one dropped by the newly drenched sheep. This is the fastest way to develop resistance.
I know - been there and got the T shirt.
10 years + ago I would have religiously drenched lambs before going into 'clean' grazing, whether that be new leys or aftergrass from silage ground.
I've now got triple resistance, and if I continued that policy with zolvix and startect would soon have resistance to them too.

We have to think about 'managing' the worm population rather than think we can eradicate it.

10 acre of PP & 20 acres of leys in arable rotation. This is the first year that worms have been a problem, I blame it on getting rid of the cattle that used to graze the PP, the cattle are coming back. I have other grass not fenced for sheep also in arable rotation used for horse haylage business & plenty of arable ground which has been arable for 40 years. I'd rather make the effort to clear out the worms than learn to live with them.

Can resistant worms contaminate new leys from a neighbour, on the feet of wildlife or contractors tyres?

 

[Poorbuthappy]

As I thought, yours is quite a unique situation. Be careful with the pp, and be aware I have heard of resistant worms surviving the plough.
I would still talk in terms of managing the worm population, even in your situation. But you have more weapons in your armoury such that you shouldn't need to rely on wormers, so with careful management resistance shouldn't be a problem.

Do you use fecs?

 

[JD-Kid]

6 weeks ummmm don't realy know what thats going to tell you to be fair thought the idea was testing the drench some of the drenchs run out of steam on day one so to be fair any time from day 2 to a time before any new worms could lay eggs

triple restance to them single dose not as combo drenchs i'm guessing .. levamisole how bad on that ??

1/2 the reson the probs took off is the advice that was given drench programs can recall every 21-28 drenching hoggets maybe 6-7 a year so did not take long for things to take off

don't know many farms with clean paddocks nemo can last up to 2 years + so spelling for a year kinda blows that one out of the water cropped padocks would be clean and then be worked up again so most restance would be plowed under

the cattle thing ummm sounds good on paper but sheep would lower cattle worms by grazeing to the deck cattle can't graze down low eneff to realy lower sheep worm numbers

PBH i would wonder more about breeding than worms and try to build up the blood lines to handle the worms .. stud breeder we get some rams off think total drench free last year years before that at radom some rams on a nill drench program those were ranked unknowen to the person doing data IE only had a marker tag nothing on file .. think ewes been non drenched for 15-17 years i guess
first few years kind thought ummm he's cocked it up ewes crashing a bit between lambing and weaning think a lot of ewes that crashed put in a mob by them selfs after weaning if they did not pick up down the road

we done alot of trial by fire here and it's lowered our use of drench's to totaly remove them ummmm could be done but a high culling rate may happen both on ewes that can't handle them and also ewes useing all there engey trying to fight them off