JSchroeder said:Based on the dates you gave, you were trying to get her to breed back at 30-40 days which is tough even with a CIDR but Lutalyse is useless for that.
Lutalyse won't bring an anestrus cow into heat, it will only induce it in cows that are already cycling. As you guessed, a CIDR is what you want to try.
Cowboy said:Every one needs to keep in mind a few simple rules for the breeding cattle --
First -- Prostoglandin (Lutelyse or Estrumate) will only work on a cow that is a: cycling and b: mid-cycle WITH a functional CL.
Any time you inject a cow that cycled less than a week earlier or one that has never cycled , you will in most cases FAIL to get her to come into heat with that shot.
A cow that has calved say 30 days ago, and has so far not cycled, will not come in with a single dose of Lutelyse -= period!
A cow that has cycled 2 days ago will not come back in -- period!
If you feel you need to try and bump a cow forward in the calving season -- a Cidr (Progesterone based product) will act as an artifical CL. It fools them into thinking they are about to cycle back, and alot of them will before they normally would on thier own.
These drugs are not cure alls, and I see alot of quitions or comments directed at the majic drug Lutelyse. It is not a majic drug, it is a natural occuring hormone already in the cow's uterus. We , by injecting them with it, are giving them hundreds of times the normal amount present, and it over-rides thier natural balance -- tells the CL to go away, and a follicle is formed after all progesterone is gone from the system. This works well in normally cycling cows, buy it will do nothing for them unless all the above are met.
Hope this helps every one get a handle on when to use what -- repeated shots in some cows that are nor receptinve CAN, and some times does, make them imune to reponses later on. Use this and any other drug with discretion, and they will work much better!
Best of luck on your breeding season!