Listed below are some quick facts of information from “Artificial Insemination and Estrus Synchronization for Beef Cattle Fact Sheet”, written by Taylor Davis.
Estrous Synchronization
- Reduces time required to check heat when using AI
- Shortens calving season
- Improves overall management
- More handling time
Artificial Insemination
- Genetic Selection
- Potentially improve genetics
- 87% of the cow herd reflects the genetic makeup of the herd sires after 3 generations.
- Increase weaning weights– (Anderson et al., 2003 – +110 lbs from AI calves)
- Reduces the expense of keeping bulls
- Feed, vaccinations, veterinary costs
- Controls venereal diseases
Body Condition Score, Nutrition, and Reproduction
- Cattle that are too thin or too obese may have reduced reproductive capabilities compared to moderate cattle.
- Learn how to utilize Body Condition Scoring practices (Scale 1 to 9). A score of six or seven is desired at calving and five at breeding.
- Feed heifers separately from cow herd. Their nutrient requirements are different.
**Heat stress and rough handling can decrease conception rates**
Hormones in Ovulation:
Progesterone (P4)
- Produced in the ovary by the Corpus Luteum.
- Maintains early pregnancy.
Prostaglandin F2 α (PG)
- Regresses the fully developed CL (luteolisis).
- Produced by the uterus.
- Will not stimulate estrus if cattle are not cycling.
- Can cause abortions in cows and humans. Use gloves.
Gonadotropin Releasing Hormone (GnRH)
- Produced in the Hypothalamus (Brain).
- Target organ: Anterior pituitary (Brain).
- Causes the release of FSH and LH (ovary stimulating hormones).
- Luteinizing Hormone (LH) – triggers ovulation and development of corpus luteum (CL)
- Follicle Stimulating Hormone (FSH) – stimulates follicular growth, spermatogenesis, estrogen release
How to Detect Heat:
- Gomer Bull with Chin Ball Marker
- Heat Mount detector
- Paint Stick
- Computerized
- Visual Detection
AM/PM Rule
- British and Continental breeds:
- Animals in heat in the morning – breed in the afternoon
- Animals in heat in the afternoon – breed the next morning
What is Timed Artificial Insemination?
- Designed to
- control follicular wave dynamics
- induce regression of the corpus luteum (CL)
- induce the ovulation of a dominant follicle
- The technician can calculate when ovulation will occur and inseminate animals accordingly
**Fertility is a major component of beef cattle production**
For more information on Beef Cattle Reproduction from the University of Florida, please click here.
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