Another first lamb dose & fec test

[unlacedgecko]

I would say that a ewe that needs worming is a failure --- regardless of the grazing system

They should have established enough resistance by then to do without
Trouble is that hardly anyone measures/selects for parasite resistance ---terminal sire breeders are probably the worst due to the low negative correlation between growth and resistance . Every time they select for good growth you select for poor resistance ---select for growth with no check on where you are going with resistance over many years =sheep very susceptible to worms

Surely the best and cheapest way to reduce pasture worm burdens is to have ewes that naturally hoover up the worm eggs?

I'm absolutely fascinated by the concept. I think breeding parasite resistant sheep is one of the most important and exciting aspects of the industry currently.

 

[neilo]

What do you drench ewes with pre-lambing Neil? We used Cydectin LA once 3 years ago and was very impressed with it. I'm considering using every 4-5 years just to keep the worm burden under control. I rotate between and clear and yellow drench for the ewes and this is generally the only time they get done.

I've used levamisole for the last 2 years (actually Levafas Diamong this year, as suspected possibility of rumen fluke), with the idea that any levamisole resistant worm eggs that get shed, and are picked up by lambs, will get killed by an ivermectin drench for them.
Pre-lambing is the only drench I'd give to a fit ewe too.

 

[neilo]

What would folk recommend for lambs as second worm dose end of June..cydectin or a levaside? Do they both do the same job?

Both would do the same job, as long as you have no resistance to either. Without knowing that, wormer choice is just a stab in the dark.

 

[neilo]

I would say that a ewe that needs worming is a failure --- regardless of the grazing system

They should have established enough resistance by then to do without
Trouble is that hardly anyone measures/selects for parasite resistance ---terminal sire breeders are probably the worst due to the low negative correlation between growth and resistance . Every time they select for good growth you select for poor resistance ---select for growth with no check on where you are going with resistance over many years =sheep very susceptible to worms

Surely the best and cheapest way to reduce pasture worm burdens is to have ewes that naturally hoover up the worm eggs?

But that natural resistance is known to wain around lambing time, allowing them to shed loads of eggs onto pasture for a few weeks. That's always been the idea of using a lambing time wormer, and I've yet to see any real evidence to suggest it's not still worthwhile.

In an intensive/higher stocking rate situation, is there any evidence to suggest that some ewes don't lose that resistance over lambing time?

As for the arguement for selecting terminals on FEC, I would suggest there are greater economic gains to be made for selecting for out & out production in terminals, than by drastically slowing those gains in performance by reducing selection pressure in order to select on another trait (FEC). If the maternal lines they are used on are selected using FEC ebv's, they should have a large bearing on the lambs resistance themselves, without diluting the performance potential from the terminal sire. Obviously if the sire is one of those 'hack of all trades', then there is an arguement for selecting those on FEC too perhaps.

Personally, I like the theory behind it, but am a little more dubious this year. I bought a Lleyn last year, who was top 1% on FEC ebv, having been tested himself, as well as his sire and plenty of his half sibs. Those figures should be rock solid, you would think. This Spring, his FEC ebv's places him in the bottom 10% of the breed. You'll perhaps understand why I am a little less inclined to trust it now.

 

[sheepwise]

I would say that a ewe that needs worming is a failure --- regardless of the grazing system

They should have established enough resistance by then to do without
Trouble is that hardly anyone measures/selects for parasite resistance ---terminal sire breeders are probably the worst due to the low negative correlation between growth and resistance . Every time they select for good growth you select for poor resistance ---select for growth with no check on where you are going with resistance over many years =sheep very susceptible to worms

Surely the best and cheapest way to reduce pasture worm burdens is to have ewes that naturally hoover up the worm eggs?

Why do high growth rate sheep have low resistance to worms? Logic would suggest the opposite would be the case.

 

[Tim W]

But that natural resistance is known to wain around lambing time, allowing them to shed loads of eggs onto pasture for a few weeks

heritable trait ---some shed more than others , hence we breed for those that don't shed as much. Looking at my ewes now 6 to 9 weeks after lambing and still averaging 60epg (apart from the Charollais of course )

In an intensive/higher stocking rate situation, is there any evidence to suggest that some ewes don't lose that resistance over lambing time?

Yes, the trials we did were at 12 ewes/acre on good grazing

As for the arguement for selecting terminals on FEC, I would suggest there are greater economic gains to be made for selecting for out & out production in terminals, than by drastically slowing those gains in performance by reducing selection pressure in order to select on another trait (FEC)

But every time you gain that extra little bit of carcase you loose a bit of worm resistance which means more worms to infect lambs and more worms for the dams to hoover up
The gains that are made annually in carcase are quite small ---it would be quite easy to make large initial gains in FEC if breeders & breed associations had a bit more foresight

I have now had terminal sires for 5 years (I think ) and I have to admit that they are the most dysfunctional things I have had to work with
Without exception every ram and ewe I have bought in has had problems ...daggy/prone to scald & footrot/wormy/poor fertility and downright stupid to match
Plenty of culling and selective breeding for functionality is starting to produce something that I would consider using

 

[Tim W]

Why do high growth rate sheep have low resistance to worms? Logic would suggest the opposite would be the case.

Don't know ???
Will have to ask the boffins ----

 

[Northeastfarmer]

What's noromectin injection like? I did my ewes after they lambed with that this time

 

[Woolless]

I did another fec on the mob of lambs which were sitting at 100 epg last Friday tonight. Six days later they are up to 550. Get those nemo lambs dosed @hubbahubba!

 

[neilo]

What's noromectin injection like? I did my ewes after they lambed with that this time

IIRC, it's just the same as drenching them with a clear drench.

 

[Northeastfarmer]

IIRC, it's just the same as drenching them with a clear drench.

Like cydectin...

 

[neilo]

Like cydectin...

No, Cydectin has a residual effect. Ivermectin has no lasting effect, just kills those susceptible worms that are present.

 

[Northeastfarmer]

No, Cydectin has a residual effect. Ivermectin has no lasting effect, just kills those susceptible worms that are present.

Ah ok thanks, I only worn the ewes once a year

 

[hubbahubba]

I did another fec on the mob of lambs which were sitting at 100 epg last Friday tonight. Six days later they are up to 550. Get those nemo lambs dosed @hubbahubba!

I don't know why my vet as saying I should leave it for a while. Could it be if I do them now at a lowish count of 100epg I could end up doing them again quite soon?

 

[Woolless]

I don't know why my vet as saying I should leave it for a while. Could it be if I do them now at a lowish count of 100epg I could end up doing them again quite soon?

Possibly. If they were sitting at 100 epg nemo having already had a dose, or if it was strongyles, I probably would sit on my hands. But my guess would be that the nemo count will only be going one way. Test them again?

 

[GrannyAching]

Possibly. If they were sitting at 100 epg nemo having already had a dose, or if it was strongyles, I probably would sit on my hands. But my guess would be that the nemo count will only be going one way. Test them again?

What happened to "one nemo egg is one too many - dose immediately" which I have seen so often on this forum?

 

[Woolless]

What happened to "one nemo egg is one too many - dose immediately" which I have seen so often on this forum?

For a first dose, that may be the best response. After that, mine seem to develop a resistance so that there is a background level without the rapid rise and concurrent problems. I will know more this year after doing my own regular fecs.

 

[Tim W]

For a first dose, that may be the best response. After that, mine seem to develop a resistance so that there is a background level without the rapid rise and concurrent problems. I will know more this year after doing my own regular fecs.

I tend to agree---- I have just dosed one group for nemo --they had a high cocci count (and signs of ) which I think brought the nemo threat up the scale a bit
Just down the way I have another mob that have had low nemo levels for the last few weeks but haven't been treated as they are cracking lambs with no signs of ill thrift

Two other mobs have had no drench at all so far ---lambing later to avoid nemo rise helps

 

[GrannyAching]

For a first dose, that may be the best response. After that, mine seem to develop a resistance so that there is a background level without the rapid rise and concurrent problems. I will know more this year after doing my own regular fecs.

Fair enough. I can see now that your post does actually say that so apologies. I think I was focussing on the fact that the OP hasn't dosed yet so it is a first challenge.

 

[hubbahubba]

I dosed the 100epg nemo lot yesterday. And then two other lots I was foot bathing I dosed a few dirty lambs and marked them. Start lambing 25th March. A good few lambs high 30kg's but just as many little runts all the same.