1. The document discusses methods of semen collection in various farm animals including bulls, rams, bucks, boars and dogs. For bulls, the main methods are using an artificial vagina, massage, or an electro-ejaculator. 2. Factors that can affect the conception rate of artificial insemination include semen quality, preservation and transportation, as well as the skill of the inseminator and environmental conditions of the animal. Proper collection, handling and thawing of semen is important to maintain sperm viability. 3. Detection of estrus and cleanliness during insemination also impact conception rates. Maintaining the correct temperature of water during thawing and proper

1. VETERINARY OPTIONAL
for UPSC CSE
Paper-1
ANIMAL REPRODUCTION
Lecture -4
Semen Collection in Farm Animals
by Dr. Ankesh Bisla

3. Topics to be Covered
1) Semen Collection in Bull, Ram & Buck, Boar,Dog
2) Factors Affecting conception rate in AI

4. Semen Collection in Bull
There are 4 methods for collection of semen in bull .
Concept → ejaculation + collection
Ejaculation → bull need a reflex to ejaculate
Collection → we need a equipment for its collection . For e.g. Graduated Tube

5. Collection from vagina after natural service

6. ARTIFICIAL VAGINA

7. Massage
Method

8. ELECTRO-
EJACULATOR

9. Collection from vagina after natural service

10. AV / Artificial Vagina
• A V – Artificial Vagina – This is the best method and is commonly used in all species.
• In bull, the Cambridge model of A V is used.
• It consists of a rubber cylinder that is 7 cm in diameter and 42 cm long.
• one side for air and water entry.
• Then there is an inner rubber liner that is longer than the cylinder and it is turned back on both ends of the cylinders.
• Then there is a rubber cone that is 20 cm long.
• Then there is a graduated glass tube of 10 ml which is attached with the rubber cone.
• Half to 2/3 of the space between the Cylinder and inner rubber liner is filled with water and at the time of filling the
temperature of the water is 500 – 600c.
• Now the air is injected through the valve until the cylinder’s openings are closed due to the building of the inner liner. At
the time of collection, the temperature of A V should be 400 – 450c.
• A V is lubricated before collection of the semen.
• Note
 If the temperature is too high → Bull may refuse to mount the A V forever.
 If the temperature is low → unable to stimulate the ejaculatory reflex.
 In the bull for collection, the temperature of A V is important whereas in stallion the pressure of A V is
important.

11. Massage Method
• The hand passed in the rectum and the ampullae and seminal vesicles are
massaged with hands till the ejaculation occurs.
Disadvantage:
 Sometimes massage of ampullae stimulates urination.
 Skill & experienced needed.

12. ELECTRO-EJACULATOR
• By Electro – Ejaculator – It has been successfully used in Ram, Buck, and Bull.
• In the bull, it is used if the bull refused to mount the A V or it is suffering from abnormalities of the
hind limbs.
• It consists of electrodes that run at 110 volts.
• The probe should be lubricated with non-insulating lubricant, electrodes are inserted 30-45cm in
the rectum and fixed on the ampulla and seminal vesicle.
• Then the current is passed and 5-10 stimuli of 1-2 seconds are provided after every one second.
• The semen collected by this method is of large volume due to excessive secretion of the accessory
sex glands.
Disadvantage:
 May lead to Ataxia
 Painful to bull
 Concentration of spermatozoa is low in semen are if
compare to AV method

13. Semen Collection in Stallion
• Ideal method to use in stallion is AV.
• AV for stallion is comparatively larger.
• AV of stallion also have handle so that it is held firmly as stallion have a vigorous thrust at
the time of ejaculation.
• Before ejaculation stallion’s penis should be properly washed with mild soap solution &
rinsed with clean water to remove smegma & other debris.
• Temperature of AV should be 45-50°c
• Ejaculation is completed in about 15-20 sec
• Collection bottle are warmed to body temp. & are attached to AV
Note#
Smegma is a secretion of the oil glands around the genitals. For men, smegma often appears under the foreskin
of the penis. In women, it's most likely to appear between the folds of the vagina's labia or around the clitoral
hood. Smegma has several distinct characteristics: thick, cheese-like consistency.

14. Semen Collection in Ram & Buck
1) By collecting semen from the vagina of ewe after natural service :
 using a glass pipette attached to rubber bulb for suction.
 penis & vagina should be cleaned before mating.
 Semen unsafe to use as it is contaminated.
2) By Using Artificial Vagina :
 Rubber cylinder 20cm long and 5cm wide in diameter.
 Inner rubber liner 25 cm long & 3.75 cm in diameter.
3) By Electro-ejaculation :
Before inserting a suitable size probe , the rectum of ram/Buck should be emptied with warm water enema.
Gradually increasing current stimulation (2.5v to 8v peak ) are given with current on for 2-5 sec and off for 2-3 sec.

15. Semen Collection in Boar
 In boar maintenance of proper pressure is very crucial for ejaculation.
 3 Fractions in ejaculation :
a) Pre-sperm fraction → seminal fluid which have bacterial count & gelationous material From cowper”s gland.
Note# In natural service presperm fraction is use to seal the the cervix & prevent loss of semen.
b) Sperm-rich fraction → All ejaculate in one time or b/w interrupted fluid of seminal vesicle.
c) Post-sperm fraction → contain 20% of gelatinous material
1) Gloved hand method :
a) Boar is allowed to mount on the estrous female or phantom.
b) Operator stand on the right side of dummy.
c) As boar mount & protrude the penis, operator catches twisted glans penis in gloved
hand & exerts pressure on it so as to stimulate the ejaculation.
d) Semen collected in wide-mouth bottle fitted with gauze filter.
2) Artificial Vagina :
a) Design to provide optimum pressure to spirally twisted cranial portion of penis.
b) Temp → 45°-50°c , rubber cylinder→ 12.5cm length & diameter→ 4.5cm
c) Small pieces of sponge are place b/w hard rubber cylinder & inner rubber lining to apply pressure on
twisted end of penis.

16. Semen Collection in Dog
1) Artificial Vagina :
 AV of dog 20cm in length & 20cm in diameter
 Temperature of AV should be 40-42°c
 The dog penis is stimulated through prepucial sheath & after its erection it is introduced into the AV
Precaution
 In hair breed ,hair should be avoided to come in b/w AV & penis
 Make sure dog don’t urinate & mark the area before semen collection as it will result in urination & urine will come out with
semen deteriorating its quality. To avoid this, few drops of semen should be discarded on the ground.
2) Manual manipulation :
 Simplest & cheapest method of semen collection in dog.
 Estrous bitch exposed to dog , when dog show interest 3-4 cm penis of dog is exposed by pushing prepucial skin caudally.
 Base of the penis is grasped behind the Bulbus glandis & moderate pressure is applied by fingers.
 Collected in glass/plastic funnel attached to warm tube into a warm vial to prevent leakage.
 Maintening proper pressure behind bulbus glandis is important.

17. Bulbus glandis
• “Bulbus glandis” are located on either side of the base of the penis. When
a dog becomes aroused, the bulbus glandis swell with blood, creating two readily visible
bumps.
• Functions: Bulbus glandis is not a gland . It helps to complete the “coital tie”, which keeps the male and
female dogs locked together until mating is complete.

18. Copulatory tie

20. Factors Affecting conception rate in AI
Factors affecting conception rate following AI:-
1.semen collection – collection of semen in a contaminated equipment which might lead to
deterioration of sperm.
2. Semen quality – if microscopic & macroscopic examination is not done properly sperm is not able to
fertilse ovum.
3. Semen preservation – if diluent are not prepare accordingly or proportion of semen & diluent not
properly made.
4. Transportation of diluted semen – unable to maintain required temperature in cases of long
transport.
5. Thawing – Temperature of water( should be 35°C – 37°C) is not maintained in which straw from liquid
nitrogen cylinder is placed.
6. Unskilled worker (AI, 45 degrees than 90 degrees)
7. Removal of Dung from the rectum
8. Proper opening of vulvar lips to avoid infection
9. Environmental condition of the animal
10. Detection of animal in heat.