Which agent is used to induce parturition in cows?

Which agent is used to induce parturition in cows?

• A. Oxytocin
• B. Progesterone
• C. PGF2a
• D. Estradiol

Answer: (C)

Inducing parturition in cows relies on removing the hormonal signal that keeps pregnancy ongoing. The corpus luteum produces progesterone to maintain pregnancy, so triggering luteolysis and reducing progesterone allows the uterus to become contractile and start labor. Prostaglandin F2 alpha does exactly that: it causes luteolysis of the corpus luteum, progesterone falls, and the cow progresses toward birth. After the hormonal environment shifts, contractions can be supported or intensified as needed. Oxytocin is good for boosting or sustaining contractions once labor has begun, but it doesn’t reliably induce labor on its own because the progesterone block must first be removed. Giving progesterone would prevent labor, not induce it. Estradiol can influence uterine activity but is not a standard, reliable inducer of parturition in cows.

Inducing parturition in cows relies on removing the hormonal signal that keeps pregnancy ongoing. The corpus luteum produces progesterone to maintain pregnancy, so triggering luteolysis and reducing progesterone allows the uterus to become contractile and start labor.

Prostaglandin F2 alpha does exactly that: it causes luteolysis of the corpus luteum, progesterone falls, and the cow progresses toward birth. After the hormonal environment shifts, contractions can be supported or intensified as needed.

Oxytocin is good for boosting or sustaining contractions once labor has begun, but it doesn’t reliably induce labor on its own because the progesterone block must first be removed. Giving progesterone would prevent labor, not induce it. Estradiol can influence uterine activity but is not a standard, reliable inducer of parturition in cows.