Jane Naramore, Veterinary Assistant 

Fall calving herds are soon approaching breeding season.  If you plan to A.I. this season it’s time to look at your calendars and make preparations now.  This will make breeding season go much more smoothly.

First, consider your options:  Timed breeding after synchronizing heats, or breeding on natural heats.  To optimize your time, get those cows and heifers synchronized.  Not only will you spend less time working your animals, but your calving season will be substantially shortened!

Timed breeding can be accomplished in many different ways, but no matter how you accomplish this remember heifers should be given at least 2-4 weeks more to get bred. This means synchronization should start 2-4 weeks earlier than cows.

Rose Hill Veterinary Practice, P.C. (RHVP) recommends the following protocol:

Before starting:

1.        Identify the animals to bred by visible ear tags and/or brands

2.        Have semen on hand or arrange for delivery to RHVP with the cow/bull record

DAY 1:  Insert CIDR’s, inject 1.5cc Fertagyl (GnRH) intramuscular (IM). Administer with a 3cc syringe and 20 gauge 1” needle

DAY 7:  Remove CIDR’s, inject 6cc Lutalyse (Prostaglandin F2alpha) IM.  Chalk or use other heat detection devices.

Watch for standing heats (early AM & late PM).  Note I.D. number and breed 10-12 hrs after first standing heat.

56-60 hours after removing CIDR’s breed all cows which have not shown standing heat and inject 2.0cc GnRH IM or IV(intravenously)

Visable secondary signs of heat: 

1. Mounting other cows
2. Vaginal mucous discharge
3. Swelling and reddening of the vulva
4. Bellowing, restlessness, and trailing
5. Rubbed tailhead hair and dirty flanks
6. Chin resting and back rubbing
7. Sniffing genitalia
8. Head raising and lip curling
9. Decreased feed intake and milk production
10. Metestrous bleeding, bloody mucous discharge (especially heifers)

A cow is in standing heat if she stands to be mounted and does not move away from under the animal that is mounting her. 

If you have questions, want to discuss alternative protocols, or want to set up times for our staff to help, don’t hesitate to call the office at 540-987-1200 and we’ll be happy to help in any way we can.