Question

How do you arrange the correct sequence of the following procedural steps for early pregnancy diagnosis in cow?
(A) Do the insemination in adult dairy cows.
(B) Administer a small dose (2.5 mg or 0.5 ml) of Dinoprost (Lutalyse) intravenously through the ear vein.
(C) Observe critically the teat of the animal for alveolar milk to start flowing about one minute later.
(D) After 18 to 22 days and 3 hours prior to the evening milking, place the teat cannula in the left fore-teat and leave it for milk flow from the teat cistern till it ceases.
Choose the correct answer from the options given below which describe the correct sequential steps for early pregnancy diagnosis in cow.

• A. (A), (B), (C), (D)
• B. (A), (C), (D), (B)
• C. (A), (D), (C), (B)
• D. (A), (D), (B), (C)

Hint:

Breeding comes first, then draining the cistern, then the hormone injection, then observing the response.

Answer 1

The Correct Option is D

Step 1: The procedure begins with insemination (A), since pregnancy diagnosis can only be tested after breeding.
Step 2: 18 to 22 days later, 3 hours before evening milking, a teat cannula is placed in the left fore-teat and left until cisternal milk stops flowing (D). This empties the milk cistern so any later flow must come from a fresh let-down reflex.
Step 3: A small non-luteolytic dose of Dinoprost (Lutalyse) is then injected intravenously through the ear vein (B).
Step 4: The teat is observed for alveolar milk to flow about a minute later (C). If a corpus luteum is still active, this indicates likely pregnancy.
Answer: (A), (D), (B), (C).