This document discusses various methods for preparing teaser bulls to identify cows in heat for artificial insemination. Key considerations for choosing a teaser bull include mild temperament, good libido, and moderate size. Common surgical preparation techniques include vasectomy, caudal epididymectomy, penile deflection, and preputial obstruction. Non-surgical methods involve testosterone administration. Advantages and disadvantages of different techniques are provided, such as vasectomized bulls maintaining libido but risk of spreading venereal disease, and penile deviated bulls better detecting cows in heat with no disadvantages noted.

1. Importance
• To identify femals for artificial insemination
• Hastenig the on set of cycling in young heifers
Cows to being cycling earlier.•
• To identify the animals displaying
oestrus unnoticed
signs of behavioural

2. Choosing a teaser bull .
• Mild temperament
• Good libido
• Moderate to small size
• Ideally surgery should performed in smaller condition
for easy restraining

3. CONT…
• specially veneral disease
• Use yearling bull
• Selected for culling for low genetic merit
• Castrate or sell at the end of breeding season

4. Techniques of teaser bull preparation
1.Vasectomy
Procedur
e
•
Application of local anesthesia
• Skin incision
• Identification of ductus deferens
Fig.1 Skin incision

5. CONT…
• Placing of ligature
Fig.2Spermatic cord freed
• Removing of ductus deferens
• Closing of skin
Fig.3 Ducdus deferens isolated and
removed

6. 2.Caudal epididymecectomy
Procedure
• Preparation of scrotum
• Infiltration of local anesthetic
• Incision directly over the tail of the epididymis
• Grasp the epididymis and exteriorize the entire
epididymal tail

7. CONT…
3.Penile deflection
Procedure
• Prepuce is surgically relocated at an angle of about 45
degree lateral from the midline.
• Penis touches rump of the cow rather than the vulva

8. 4.Preputial obstruction
Procedure
• A subcutaneous puerse string suture
proximal to preputial opening
is placed 1 inch
• Many times breakage of the suture
.copulation,phimosis, paraphimosis
• Closing the prepuce and making preputial fistula for
urine

9. 5.Penile fixation
• Penile fixation anterior to the scrotum
• Penile fixation posterior to the scrotum
• Retractor penis muscle fixation

10. Non surgical methods
• The administration of testosterone ,propionate .the
is 100mg testosterone propionate every third day .
does
• Alternatively 150 mg may be administered weekly
• Testosterone administration should being 3 week before
the teaser is used and administration should continue
through the breeding season.

11. Penile blocked
bull
Advantages
• Allow for normal mounting
• Prevents extension penis thus insemination
• Healps prevent the spread of venereal disease
Dis advantage.
• Effect for only one year.

12. Vasectomisebull
Advantage
s
Normal libido
Breeding
stimuli
rate to AI
by sterile bull increase the conception
Disadvantage
s
Can spread venereal

13. Penile
deviated
bull
Advantage
s
• Better for detecting oestrous femals than either
vasectomise or penile blocked males
• No venereal disease spreading
Disadvantages
• No disadvantages noted

14. Epdidymectomized bull
Advantages
• Reiatively simple to performe
• Economical methods of preparing a teaser bull
Disadvantage
s
• Can spread venereal disease