Semen evaluation

Question 1

Semen also contains cells other than sperm (COTS).. What are they?

Answer 1

– RBC, WBC, bacteria, epithelial cells. These are also assessed

Question 2

The sample indicates the physiological condition of the testes and tubular tract – mainly retrospectively…Many factors can adversely influence the findings. List some factors:

Answer 2

Avoid sunlight
Temperature shock – sudden changes, or above 38 deg C. Don’t let stay in the AV
Rough handling
Soaps
Disinfectants
Water
Blood
Urine

Question 3

Traditional “Full Book” =

Answer 3

45 mares natural service, or 120 mares AI

Question 4

DSO provides an indication of the functionality of the…..(anatomically)

Answer 4

seminiferous epithelium

Question 5

How would you assess/ set about working out the DSO?

Answer 5

Collect the stallion twice daily for a week

The total sperm in the collection on the 7th day is equivalent to the DSO (in the order of 3000 million)

Question 6

How is DSO useful?

Answer 6

It can help with determining the size of the book – need minimum of 500 million, morphologically normal sperm/service

Question 7

When calculation BSE-
Collect semen twice, at one hour interval
Samples can be considered representative if:

Answer 7

Volume of both ejaculates is approximately equal
Total sperm in second ejaculate is about half the first
pH of second ejaculate is the same or slightly higher than the first
Motility of the second ejaculate is the same or slightly more than the first

Question 8

Describe the 3 fractions of the ejaculate and their relevant volumes..

Answer 8

3 fractions: 1st is watery (20ml), 2nd is creamy and sperm rich, 3 rd is gel-like with low pH (variable volume).

Question 9

As the stallion ages.. where are most of the sperm reserves?

Answer 9

Note where the sperm reserves are and the percentage of reserves stored in different areas
Tail of epididymis is very important (61%)

Question 10

Increased frequency =

Answer 10

decreased sperm per ejaculate

Question 11

In relation to testicular degeneration, what anatomical area is most commonly noted? What class of horse does it commonly affect? Causes?

Answer 11

Seminiferous tubules degenerate
A common problem in older stallions
May be heritable
Also environmental causes

Question 12

The acrosome

contains …………..These are necessary for:

Answer 12

-enzymes
-the sperm to enter
the zona pelucida of
the ovum

Question 13

evaluation of semen should include:

Answer 13

• Volume
• Colour
• Texture
• Motility
• Concentration

Question 14

Gel fraction mainly comes from the:

Answer 14

vesicular glands

Question 15

Total volume is greatly influenced by:

Answer 15

Season

Question 16

Which fraction of semen is of greatest interest?

Answer 16

The gel-free fraction

Question 17

When should motility assessment be performed?

Answer 17

Perform immediately after collection

Question 18

What percentage of motility ratings is considered fair?

Answer 18

30-49% motility

Question 19

What percentage of motility ratings is considered poor?

Answer 19

<30%

Question 20

What percentage of motility ratings is considered good?

Answer 20

50-69%

Question 21

What percentage of motility ratings is considered very good?

Answer 21

> 70%

Question 22

Minimum recommended Individual Motility is ……. Ideally it should be …….,
particularly if ……………………………………………………..

Answer 22

30%
>60%
freezing or chilled-shipping the semen

Question 23

What is used to assess semen concentration?

Answer 23

The haemocytometer

Question 24

When do Primary and secondary sperm abnormalities occur?

Answer 24

Primary develop during spermatogenesis

Secondary develop during epididymal transport

Question 25

What is the difference between major and minor sperm defects?

Answer 25

Major defects have been associated with infertility

Minor defects have not been associated with infertility

Question 26

Define compensable abnormalities

Answer 26

These abnormalities can be compensated for by increasing the insemination dose – i.e. they DO NOT inhibit normal sperm

Question 27

Define uncompensable abnormalities

Answer 27

The abnormalities can not be compensated for by increasing the insemination dose – they DO inhibit normal sperm

Question 28

Which classification system would you be best to use when assessing semen for frozen semen processing?

Answer 28

compensable/ noncompensable

Question 29

List the 4 questions you would ask during analysis of the spermiogram

Answer 29

Identify types of defects
What is the effect on fertility?
What is the cause of the abnormality?
Can a prognosis be given?