Lut Question

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Well-known member
Dec 22, 2006
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west virginia
I put in Cidrs on 5-10-09 gave Cystorelin, pulled them 5-17-09 and gave Lut. Bred cows over the next few days, how soon (I think 14 days) can I give another shot of lut to the ones that did not cycle to come into heat. Most of the time I breed once and kick out with bull but this year I am going to watch for those who didn't catch and breed again. So I just need to know if the 14 day is right. This would put them cycling with the next group that will be synced to breed. Thanks in advance
Prostaglandin (Lutelyse, Estrumate, etc) need a viable corpus luteum to have any effect. Cows that aren't cycling won't have a corpus luteum so prostaglandin alone won't have eny effect. If they were cycling you could give the prostaglandin 5-15 days after the previous heat to induce degeneration of the corpus luteum that will cause the next heat to start.

If the CIDR protocol didn't force them into cycling I don't know what will, could it be that you just missed their heats? If you are set on AI-ing them and assuming that the CIDRs did indeed kickstart their cycle I would wait 7 days after the set time for AI and give them the prostaglandin and watch very closely for heat from 36-96 hours after the shot. The vast majority will show signs of hear from about 66-84 hours after the shot in my experience.

Or the cheapest and possibly the best route for you would be to just wait this cycle out and try and catch them when they should cycle again with the rest of those that didn't settle on the first service 18-23 days after they should have been in heat the last time. The heat following an induced heat is supposed to be a very fertile one and you won't win much time by inducing a heat. All you'll achieve is double the amount of time you need to heat detect.
So what your saying KNERSIE is that the 14 days would be ok ? I am looking for most optimum time to give the lut shot, The two that didn't cycle are as follows, one was a first calf heifer and the other a 8 or 9 yr. old cow who I am trying to get caught back up with the rest. She calved a little later than the others and trying to back her up some. She was around 45 days post partum and in good condittion. The heifer is in good condition but you know how those can be. I just want to try and get them bred back and was thinking 14 days would give ample time for them to make a new CL and that it would be strong enough to take when bred. Plus I have another group to pull cidr's next monday and this would fall within the time the would be cycling. I am pretty sure they didn't cycle or maybe just missed them, I bred several who showed no real activity but had mucas and their cevix was nice and firm, didn't have any problems getting gun through them at all. Have bred off just that before with good results. I am no rookie at this but just trying to see if others have gave the second lut shot at 14 days with good results or if something else has worked better for them after pulling those Cidrs and not seeing any signs of a heat. Thanks Again.
Neighbor shoots for day 10 to hit them with prostaglandin. Don't know for sure but seems he has pretty good luck getting them back into heat.
Day 7-13 would be better, but I believe you still don't quite grasp how it works. You need a CL to DEgenerate in order to bring on the next heat. At the time of heat there is NO CL. The CL developes out of what is left of the burst follicle from the ovulation so if they didn't cycle last time there won't be a CL and hence nothing for the Lutalyse to work on.

If the heifer and the late calver hadn't started cycling yet the Lute or the Estrumate isn't going to do any good. Like I said if the CIDR didn't kickstart the cows into cycling, Lutalyse alone is just a shot wasted. I suspect they did cycle after the CIDRs, but the heat wasn't a strong one and that they will have a stronger heat on their next natural heat which will coincide with the cows that hadn't settled on the AI.

Your other option is to use the combination of GNRH and prostaglandin, can't remember the timing by heart, never used this much and had unreliable success with this method.
KNERSIE":tbjnlxf7 said:
Your other option is to use the combination of GNRH and prostaglandin, can't remember the timing by heart, never used this much and had unreliable success with this method.

7 days. If you give the GnRH on saturday morning you give the pgf2 the next saturday morning

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