Question

High milk yielding varieties of cows are obtained by
A. Superovulation
B. Artificial insemination
C. Use of surrogate mothers
D. All of the above

Answer 1

Hint: High milk yielding varieties or cows are obtained by artificial means since mixed breeds showcase a significant raise in milk production. These artificial means include superovulation, artificial insemination and surrogacy among others.

Complete Answer:
Superovulation in cattle maximizes the number of fertilized and transferable embryos with a high probability of producing pregnancies. Artificial insemination (AI) is the method of collecting sperm cells from a male animal and manually depositing them into the reproductive tract of a female. In a surrogate pregnancy, eggs from a female or a donor are fertilized with sperm from a sperm donor to make an embryo. The embryo is implanted in the uterus of the surrogate mother, who will carry the baby until birth.

Thus, option (D) all of the above is the right answer. All the three methods stated above are effective methods of obtaining high yielding cows.

Note:
The high degree of unpredictability in super ovulatory response creates problems that affect both the efficiency and profitability of embryo transfer programs. Artificial insemination increases efficiency of bull usage, potential for genetic selection and others.