Lutalyse primer - For those that might not already know.
This site covers the bovine estrous cycle.
https://www.wikihow.com/Tell-when-a...ows,heat until a few weeks after giving birth.
There are natural hormones involved - follicle stimulating hormone (FSH), estrogen, lutenizing hormone (LH), progesterone, and prostaglandin.
Lutalyse is prostagladin - a hormone. Lutalyse will work ONLY if there is a CL present on the ovary. If the heifer has not yet cycled, lutalyse will not cause her to start cycling. If a cow has not restarted her cycle after calving, lutalyse will not jumpstart her cycle. Lutalyse works by causing regression of the CL which is present on the ovary during a portion of the 21 day cycle. You can use lutalyse to bring a cycling cow into heat. Use a 1.5" needle and give the injection IM. If the CL is present, the cow should be in heat in 1 to 5 days. If the CL was not present (with no observed heat) give a second injection 10-12 days after the first one. IF the cow is cycling, that second shot should line up with a CL present and cause her to come in heat.
Lutalyse is used to reset the heat cycle - not jumpstart. And may take 1 or 2 injections depending on where the cow is in her cycle. Usually used with AI (artificial insemination). If you use lutalyse to SYNCH (synchronize) lots of cows to be in heat at the same time and are using a bull, he may be overworked.
Lutalyse can be used to abort early in a pregnancy. Women who may be pregnant should NOT handle lutalyse.
Lutalyse comes in the original concentration and an HC high concentration. The dosage is different.
If you want to jumpstart the heat cycle, the treatment is insertion of a CIDR in the vagina with a shot of GNRH, remove CIDR in 7 days and inject lutalyse. No miracle cure. You won't force a poor condition cow into heat with this, but may rush the process up in good conditions. This treatment is also used in cycling cows to tightly group the time that the cows come into heat when AI is to be used. This results in a shorter duration for heat checking and breeding. You would NOT want to do this to a large group of cows being bred with a bull.
GNRH is also used to treat cysts on the ovary.