Routine Fertility Visits

Question 1

What does a farmer mean when he refers to a cow as NSB

Answer 1

Normal cow , Oestrus not observed, No calving problems, The cow has not been served, No RFM, The cow is not with a bull, No Vaginal discharge, More than VWP days

Question 2

What does vet mean by NSB cow can “have a jab”

Answer 2

This cow is normal, is cycling normally and no abnormalities were detected. The cow is at a stage of her cycle where a prostaglandin injection will bring her bulling. The cow will be bulling in 3-5 days. The cow should be inseminated when oestrus is observed.

Question 3

What does a farmer tell you by asking you to PD a cow?

Answer 3

This cow is normal, healthy and milking OK.The cow has been inseminated.
She falls into the PD window for this farm. She has not been seen bulling since service.No vaginal discharges have been seen.

Question 4

What is your responce if a cow PDs positive/negative?

Answer 4

+ve =No action/abort

-ve = Reassess if NSB

Question 5

Describe the process of a PD

Answer 5

Rectal Exam for Pregnancy
• Locate cervix and uterus manually.
• Scan full length of both uterine horns.
• Scan ovaries?
• Ultrasound findings: Pregnancy +/-, Uterine abnormality, Ovarian structures – corpus luteum

Question 6

What is the action of prostaglandin on a cow ?

Answer 6

Causes luteolysis
Progesterone production is turned off.
Cow comes into oestrus – 3-4 days (2-7)
Simply: Prostaglandin destroys the CL→ P4↓

Question 7

What is the action of GnRH on a cow?

Answer 7

Causes large release of LH.
This results in luteinisation of follicles or ovulation.
New luteal tissue is formed.
Progesterone production increases.
Simply: GnRH creates CL → P4↑

Question 8

What is the effect of a PRID on a cow ?

Answer 8

Progesterone Releasing Intravaginal Device (PRID)
Slow release of progesterone over 7-11 days.
Effectively acts as a temporary removable corpus luteum.
If no other luteal tissue is present, removal results in the cow coming into oestrus 2-4 days later.
Simply: PRID* pretends to be a CL → P4↑↓

Question 9

Describe the approach to uterine infections

Answer 9

• Days calved?
• Nature of discharge (colour, comsistency etc
• Is the cow ill?
• Pyometra
• Is a Corpus Luteum present? If a Corpus Luteum is present it may be persistent (admin PGs)
• A damaged endometrium may not be able to produce prostaglandin.
• Many cows will “self cure” if they come into oestrus.
• No luteolysis = no oestrus