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.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.
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.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.
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.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.
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.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.