Synchronization

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Lucky

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Has anyone used Lutalyse to synchronize a herd using natural service? I’ve got them to 90 days but only about 60% are calving in the first 45 days.
 

Ky hills

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I've never done that, but years ago when we were using it to synchronize for AI, the AI rep said that he would recommend doing it for natural service too. My concern is that depending on the number of cows it may be more than a bull could cover in a short time.
 

TCRanch

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This recent thread should be of interest to you:
 
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Lucky

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I've never done that, but years ago when we were using it to synchronize for AI, the AI rep said that he would recommend doing it for natural service too. My concern is that depending on the number of cows it may be more than a bull could cover in a short time.
The bulls are my main concern. From what I’ve read it’s still a 1-25 ratio for mature bulls. I’ve always ran 1-15 or 20 but this year I’d need to buy 1 more to get below 1-25.
 

TCRanch

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The bulls are my main concern. From what I’ve read it’s still a 1-25 ratio for mature bulls. I’ve always ran 1-15 or 20 but this year I’d need to buy 1 more to get below 1-25.
Keep in mind, just because or even if you try to sync with Lute, it doesn't mean they will all cycle at the same time. Maturity of the bull is definitely a consideration, as is his BSE, desire, condition and time of year at turnout - which somewhat coincides with desire. When the temperature hovers at 90+, their game is compromised.
 

simme

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Has anyone used Lutalyse to synchronize a herd using natural service? I’ve got them to 90 days but only about 60% are calving in the first 45 days.
I am reading this to say that you currently have a 90 day calving period with 60% in the first half of that period. I don't believe that Lutalyse will help much. Lutalyse only works if a cow is already cycling. If she is already cycling, she will cycle every 21 days during that 90 day breeding period. If she only starts cycling in the last half of that 90 days, then lute is not going to cause her to cycle sooner. If she is cycling in the first half of that 90 day period and getting settled in the last half, then the issue is why did she not settle in the first cycles. Issues there would be fertility of the cow and bull, nutrition, etc. Lute will not help with that. Lute will help to group the heats of the cycling cows into a common few days - generally so that they can be AI bred in a few day period for convenience of the AI tech. Also, lute will only work in a portion of that 21 day cycle - when the cow has a CL. First 10 or so days after a previous heat, lute will have no effect because the CL has not formed yet. If you want them to cycle earlier, a higher nutrition level and a CIDR protocol may be a better plan to get them cycling sooner. Mainly the nutrition. Hope I am interpreting the question correctly.
 

W.B.

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I would say there is a decent chance that by using lutalyse there is a decent chance that you are lowering your percent bred in 45 days In a natural service situation. I would look closer at nutrition, bcs and your bulls.
 

RDFF

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I personally think you're best off just making sure you've got plenty of bull power available for their normal 21 day cycle, and then working as best you can to improve both natural genetic fertility (cull those who don't settle within 45 days), and making sure you've nutritionally got them where they need to be. If you're not "challenging them" to be tops in fertility (by not culling hard for lack of fertility, and by using artificial crutches to get them there), you'll never be able to differentiate between the "good ones" and the "bad ones". You'll be keeping those "problem breeders" in the herd, and then you're only working backward... We all know that there's some that will breed no matter what......... and there's some that just WON'T breed too. Which one do you want your herd to be like? If you don't challenge them, and cull for it, you'll never get there. I know guys that specifically try to breed them when they're somewhat nutritionally challenged, just so that they will only end up with the most fertile ones calving. Don't know how that can be afforded... you'd have to ask them that... but I can tell you that they don't have much for breeding issues or open cows anymore!

Artificially screwing with their natural fertility cycle can also potentially have some unintended negative consequences. Is it worth it just to get that cycle down to maybe 12-15 days instead of 21? That's all that Lutalyse really gains you.

"Cowboy" on the steerplanet website explained the Lutalyse thing well, and pay attention to the red letter warning (my emphasis):


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Cowboy

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Re: Lutalyse

« Reply #7 on: May 19, 2008, 11:24:13 PM »

Every one needs to keep in mind a few simple rules for the breeding cattle --

First -- Prostoglandin (Lutalyse 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 Lutalyse -= 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 artificial CL. It fools them into thinking they are about to cycle back, and alot of them will before they normally would on their own.

These drugs are not cure-alls, and I see a lot of questions or comments directed at the magic drug Lutalyse. It is not a magic drug, it is a natural occurring 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 their 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 not receptive CAN, and some times does, make them immune to responses later on. Use this and any other drug with discretion, and they will work much better!

Best of luck on your breeding season!

Terry
 
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Lucky

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Thank for all the replys. I’m going to think on this awhile. Nutrition is definitely an issue and I’ve been working on that but nothing happens quickly. We run the bulls 4/15-7-15. We used to do 5/1-8/1 but the heat was getting to the bulls and February is always the worst for newborns so we moved it up 15 days. I’d really like to get down to 75 days and have the majority of the calves born in a tighter window. I’ve also been culling hard and the last few years and replacing with bred heifers. I still have several older cows though. I figured the Lute might tighten up the early calvers and if I could use markers we could go back and Lute the ones that didn’t settle 1 more time. I’ve been reluctant to try this as it always seems the best thing to do is let nature take it’s course.
 

simme

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I calve in the fall and wonder if that would work better for you - extreme heat makes it hard to settle cows. Got some ear blood in the cows? That might help. I would be interested in thoughts on fall calving vs spring calving in Texas. Matching the breeding time to the time that better forage is available is a consideration as well.
Pulling the bulls a couple weeks earlier each year should by definition tighten up your calving window and will automatically select for fertility in the cow herd provided they have adequate nutrition. But will increase the culling rate until the goal is reached.
 

TCRanch

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Thank for all the replys. I’m going to think on this awhile. Nutrition is definitely an issue and I’ve been working on that but nothing happens quickly. We run the bulls 4/15-7-15. We used to do 5/1-8/1 but the heat was getting to the bulls and February is always the worst for newborns so we moved it up 15 days. I’d really like to get down to 75 days and have the majority of the calves born in a tighter window. I’ve also been culling hard and the last few years and replacing with bred heifers. I still have several older cows though. I figured the Lute might tighten up the early calvers and if I could use markers we could go back and Lute the ones that didn’t settle 1 more time. I’ve been reluctant to try this as it always seems the best thing to do is let nature take it’s course.
Works for me! I just spent quality time looking for a cow; finally found her not far from the house. She was the last to calve as a heifer on 6/16/19. But I kept her because I didn't need to cull that year. Last year she moved up to 4/24 and I'll be darned if she isn't in labor now. Definitely crossing her off my cull list this year (calving wasn't supposed to start for 4 more days - give or take 10 and already 9 calves). I obviously give more leeway with heifers & younger cows. Older cows that consistently calved first but start falling behind are the ones I focus on selling.
 

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