Would you use PG600 this time of year?

[EmsoffLambs]

If I CIDR a December born ewe lamb to breed next week, is it necessary or helpful to use PG600? Or is that only really needed when the ewes are not already cycling?

[Chuckles450]

I would here. Pg600 makes it a little closer to a sure thing IMO.

[Don Drewry]

Peoples experience varies, IMO, PG600 increases the lambing rates when used in August or September.  So, I'd use it if I wanted twins and not if you want a single.  We have no lambing problems with ewe lambs with twins so I like them even if we lose a good share of them.  Single lambs occasionally get too big with a ewe lamb and I might need to be there to assist but I haven't lost any due to large singles for several years.

[karinfish]

You make a really good point Don that I had not considered.  Getting ready to CIDR about 20 replacement ewes and was only going to use the CIDR and not the PG 600.  Now will certainly reconsider!!! 

[Bigiron59]

 Touched on a point that has been discussed with some friends. You want to put selection pressure on your ewes for early breeding and twinning. Continued use of homonal minulation to cycle your females , will result in what the dairy industry has . females that will not cycle at all without drugs.
 I used cidrs in my ewe lambs last year. No pg600.  The youngest one had twins. The nice thing was concentrating the lambing for a gruop, or so I thought. They still lambed over about a 10 day period. The one ram  was a long gestation  and one was short. So did have 3 lambing events. One for each ram used.
I considered cidrs for my matures this year. Opted not to. Concentrated on making sure ewes were in breeding rig( condition score 3) and  a core gruop(25 head) that I wanted bred earlier and tight were isolated from rams for 60 days.
Seems to have worked
 Rams been in about 10 days . Have not checked ,but count yesterday was  35 ewes marked.  Historically ,98 percent of my ewes settle on single service. Not all ewes were introduced to rams at one time, as I want some lambs with different birthdates. 
I can not see any reason to use pg600 this time of year. If your ewes are so unfertile that they can't drop more than 1 embryo, are they worth propegateing.?
 One if my friends has exposed his ewes 2 weeks earlier than I have for many years. He has saved ewe lambs from those ewes over the years. He has a flock that natuarlly cyles early and has a very prolific flock of bf wether dams, normally approaching a 200 drop rate.
He implemented an aggressive ai plan 3 years ago. Saving a lot of those daughters, along with natural daughters. This year an aggressive cidr / pg 600 plan used with natuarl cover of rams. As his second cyle is about half way through, it appears that I have more ewes settled than he. It appears either the rams are not fertile enough to cover his groups, or the ewes are cycling, but may not be ovulating. Either way, lots of remarks and will now be later lambing.
His ewes are also in condition score 3 and most were isolated from rams for at least 60 days. No right or wrong In this deal, but my retained ewes will be from early born twins from non hormone induced ewes  or retained flush ewe lambs.
I will continue to cidr ewe lambs as it is a nice way to manage that gruop. No pg600 . cidr will be in10 go 14 days.Most lambs are sold out of that gruop, as they don't fit my management scheme . I will be using a ram lamb from that gruop. The one twin born out of the ewe lamb that had twins.
She lambed at 12 .5 months of age . Sire of those lambs was a ram lamb that  sired lambs at 5.5 months are age. 
 Good luck .

[EmsoffLambs]

I don't normally CIDR any of my ewes this time of year. However, I just purchased a new ewe lamb and would like her bred to Maximus before he goes back to Texas in a month. I want her bred ASAP so he's still here if she doesn't settle on her first cycle. The rest of the ewe lambs will be bred naturally.

[Chuckles450]

The only problem I see with your scenario Crystal is that you're going to waste a bunch of pg600 since you're only breeding the one ewe. It's highly doubtful you'll be risking her future fertility.

[Bigiron59]

Nor would I waste pg 600 on a ewe lamb. She has her whole life ahead of her. I guess it's up to you. I look at strategic breeding as an investment in my future . Short term bang, might be long term bust.  I will be flushing some ewes in a month? Why. It's to late to hit a banner with the lambs?  Late septber ,early October flushes historically produce the highest quality and quantity of embryos according to several people that do this. So you either do it and have late lambs, or freeze the embryos to implant next year. Either way, its a long term breeding stategy. Breeding to next gens ewe lambs or that next stud. Wethers would be the last option, so I will do it later for the better good. Same with breeding ewe lbs.  Lambing ease sire to get live lambs. First goal.
If she were mine, cidr , that needs to be in 10 days. Then she should cyle the day after pulling cidr. Your against a tight window
If she just came off a show string, fed who knows what to get her ready , its more iffy.  I have one out. Her last show will be in late Sept. She won't be ready to breed til late October. I want her home a while to clean her out get her used to my feed and she has her whole life ahead of her. She is good enough, that she may be flush candidate next year. A easy lambing ram to ensure a good delivery without damage to ewe is highest priority for me. Again ,long term goal.
Good luck

[Don Drewry]

If you follow this link it suggests that 5 or 12 days of implant time is the same result and use of PG600 "in season" has no impact.  http://www.fda.gov/downloads/AnimalVeterinary/Products/ApprovedAnimalDrugProducts/FOIADrugSummaries/UCM190797.pdf
This study shows similar results, it does suggest that a longer implant time results in a more consistent shorter period to the ewes coming into heat.  https://krex.k-state.edu/dspace/bitstream/handle/2097/18288/AudraHarl2014.pdf?sequence=1

Our experience has been very good with a 12 day period.  The first two years we injected PG600 subq on the body of the ewes.  We noticed a distinctly lower lambing percentage in ewes lambing the first week of January versus later periods.  Since then we've injected PG600 behind the ear and we've not noticed any reduction in lamb rates in the first group of lambs, in fact more of our triplets are born in the first period.

This year we left the implants in for 7 days instead of 12.  We just completed the 2nd 17 day cycle.  We had significantly fewer ewes remarked this year as we have had other years.  Normally, about 1/2 of our ewes remark in 17 days and about 1/4 get marked one more time.  This year only 1/8 of the ewes remarked.  To Crystal's original question, I still expect that a shot of PG600 would increase the chances of multiple lambs born with a ewe lamb.  Reading the 2nd link study relatively quickly I suspect part of the response is also based on where the ewe was in her cycle when implanted.  Without being implanted at best 1/4 of our ewes will lamb in the first half of January so for us the PG600 response is probably that ewes are just coming into their "season" and we are seeing some response. So, I'd adjust my previous comment and say only early January lambing is likely to have a result for mature ewes.  I suspect ewe lambs are likely to have a greater response but I don't know that for sure.

[PBCL]

I would wait 7-12 days and use 2 1/2 cc of PG 600 if you are only doing a few ewes I draw up multiple syringes with single doses fill the rest of the syringe with air and freeze them pull them out and thaw them before your next use I get the same success rate on frozen PG 600

[EmsoffLambs]

Thanks, Tony! That's what I'll do.

[karinfish]

Love reading the various responses on this thread and really appreciate the links to the research. I, like Crystal thought I was only going to have a short window to be able to get a group of ewe lambs bred to Pivatol our newest ram as well as our other Burn son but things have changed and we now get to keep them both through the entire fall and winter. So as I also have read that repeated use of PG 600 can begin to have a negative impact on the ewe over time and trying to consider implications of twins versus singles I think I will choose the big iron method for this group of 20 replacement ewes. Going to do a 12 day pull in groups of five so that worst case I never have more than five ewe lambs lambing at one time. Using the CIDRs on ewe lambs will be a first however so this will be interesting for sure!  The one very nice thing I discovered last year however is our first burn son throws lovely easy lambing sausage babies. Let's hope his half brother does the same. Happy lambing everyone!

[Bigiron59]

Karin, my experience , and others  is  with cidrs you control the window of lambing. I would have thought last years window would have been narrow ,as all bred in a 12 hr time frame. 1 rebred and stuck on day 35. However the lambing " window " here lasted 14 days. Each ram used was consistent , but each ram sired lambs with different gestation lenght.
I have cidrs being shipped Monday.  And will again cidr ewe lambs. It will be interesting  as the dorsets were sired by two different sires and the hamps were as well. But these were all shorter gestation sheep. However the hamp ram lamb was sired by a long gestation ram , and they were twins born on day 153. So will be interesting to see what shakes out.
The Dorset service is new, so who knows. Its always something to look forward to. And cidrs are not recommended in ewe lambs. But many are used.

I do have a commercial producer that uses cidrs on around a  1000 ewes . His goal is lambing Sunday pm through Friday am each week. First year was off 30 hrs. Made adjustment and last year was much better. He thinks he has it figured out this year. Each flock will have a window, based on your genetics and management.
I feed once a day at 4 pm every day during lambing. That helps influence time of lambing.
It will be interesting to see what you find out with your cidred ewe lambs.

[Honey Tree]

Shane, by feeding at 4pm, what was the window of time that your ewes lambed?

[Bigiron59]

90 percent if lambs are born from 3 pm to 9 pm. Always be that 5 to 6 am out lier and I can tell at feeding time if that one will be yet today . 8 pm check will determine if its gonna be a midnight lamb, which is not gonna happen , as I will intervene an get it done if dialated .
Hair cross ewes still are primitive enough that 90 to 95 percent are born from 5 am to 9 am with some early afternoon. Have never had any night of evening in  the 3 years I have had them. One years ewes were fed tmr with feedwagon at 5 pm . other years free choice round bales with grain feeding at 4 pm.
Other have other ideas. Time can not vary, or your lambing window will not be consistent. Most people think they consistantly feed "on time". But when they kept logs . most found the " consistent " time of feeding varied as much as 8 hrs over course of a week. Nothing consistant about that, except it was consistently inconsistent.