-
What is the importance of getting cows pregnant? (3)
increase milk production, reduce replacement costs, accelerate genetic improvement
-
What technique is used on the majority of US dairies for first service?
AI to natural estrus
-
The MAJORITY of the variation in preg rate between farms is due to...
management/ environment
-
What are advantages of synchronization? (8)
efficient method of use of AI, organize farm labor, reduce need for estrus detection, schedule hormone treatments, dry off (know exactly when to), know expected calving dates, record management, improves service rate
-
How can you approximate the pregnancy rate?
service rate x conception rate
-
What is service rate?
% of eligible open cows that are bred per unit of time (21 days); equivalent to heat detection rate
-
What is conception rate?
% of bred cows that become pregnant, # preg/ # inseminated, changes with pregnancy diagnosis method
-
What are the challenges to synchronization protocols? (5)
labor, compliance to specific protocols, accurate records, public perception, good nutrition and management is key
-
GnRH works at the __________ to cause...
hypothalamus; induce ovulation of ovarian follicles.
-
Prostaglandins work in the __________ to cause...
uterus; luteolysis
-
Progesterone works in the _________ to cause...
ovaries; increase progesterone in the blood
-
CL is refractory for ___________.
5 days (prostaglandin won't work)
-
Administration of PGF induces...
estrus followed by ovulation 2-5 days after injection.
-
__________ induces abortion in pregnant cows.
Prostaglandin (you need the CL to maintain the pregnancy)
-
Describe the ovsynch protocol.
GnRH--(7d)--> PGF--(56hr)--> GnRH--(16hr)--> timed AI
|
|
