This document summarizes the utilization of sex-sorted semen in cattle production. It discusses how sperm are sorted based on their X and Y chromosomes into sexed semen with 80-90% accuracy using flow cytometry. The sexed semen allows producers to limit offspring to a single sex. The document outlines the sex-sorting process and provides examples of its use in the dairy industry to produce more valuable female calves and in the beef industry to produce male calves. It also briefly discusses potential issues like calf welfare due to killing of excess male calves.

1. UTILIZATION OF
SEX-SORTED
SEMEN
Amit Gnawali
M.SC. Animal science
Department of Animal Breeding and
Biotechnology
Agriculture and forestry university (AFU)
MARCH
2021

2. Introduction
❖Sperm contains an X and a Y
chromosome.
❖Ova contains only an X chromosome.
❖When fertilization occurs
X-sperm + X-ova = XX female
Y-sperm + X-ova = XY male

3. 3
SEXED SEMEN
❖Sexed semen is semen that has
sorted by its X and Y chromosome.
❖Allows a producer to limit
offspring to a single sex.
❖ 80-90% of accuracy.

4. How are Sperm Separated?
4
❖Identifying difference between X and
Y chromosomes.
❖X – chromosomes contains 3.8% more
DNA in cattle
❖Flowcytometry method is best
method with more than 90% accuracy.

5. Sexed Semen Process
5
❖ Flowcytometry is commonly used
❖ Fluorescence-Activated Cell Sorting
❖ Electrostatic cell sorting

7. Artificial Insemination
❖Use only in herds with AI pregnancy rates of 60% or more with
conventional semen.
❖Healthy cycling females with good body condition, preferably heifers.
❖Animals observed in standing estrus. If using fixed-time AI, make sure
a high percentage of the animals were in estrus before fixed-time AI.
❖Inseminate heifers with sex-sorted semen once and subsequently
with conventional semen if they do not conceive.
❖Be extremely careful with semen thawing and handling.
❖The inseminator should have experience and be known to achieve
good pregnancy rates. 7

8. Commercial Bovine Production
❖ Dairy industry
❑ Female are more valuable
❑ Greater selection pressure
❑ Herd size increases
❑ Replacement of superior heifer
❑ Annual 9- 15 % genetic progress (Sedial, 1999)
❖ Beef industry
❑ Male are more valuable
❑ They use Y enriched semen for quality beef. 8
REPLACED BY

9. Multiple ovulation and embryo transfer
❖ Invitro fertilization
❖ Reverse sorting
9

10. 10
CALF WELFARE
❖ 0.1% of the bull calves produce
sufficient sires for the dairy
industry
❖Inhumane killing of male calves

11. Applications
❖ Reduced dystocia by 20%
(Seidel, 2003)
❖ Improved biosecurity
❖ Increased rate of genetic gain
11

12. THANK
YOU!
Amit
Gnawali
Phone
9847120271
Email
agnawali97@gmail.com