Lecture 3 Flashcards
What is the natural-service herd dependent on for repro success?
Healthy breeding sound bulls
What type of cow usually does natural service herds
Beef cattle
How many bulls should you have?
One bull per 25 open cycling cows
What type of bulls should you buy?
Buy virgin bulls at least 60 days before breeding season to allow time to adjust to feed ration
Obviously disease free
When is a bull typically ready to breed?
15 months old
What are requirements for sound bulls?
Physically sound and in good health
Functional repro system
Fertile spermatozoa
Free of venereal diseases
What accessory sex glands does the bull have
Ampulla
Vesicular glands
Prostate
Bulbourethral
Which accessory sex gland has the ability to affect bull fertility
Vesicular gland
What things (anatomy wise) can affect bull fertility
Scrotum, testicle, tail of epididymis, seminal vesicle, prepuce
What does the BSE consist of
ID and history
Physical exam
Reproductive exam
Collection and examination of semen
What do you look at in the semen collection?
Motility and morphology
What do we not care about with bovine sperm?
Concentration
What does the PE consist of?
Structural soundness BCS Eyes Feet/legs Wounds, physical defects Generalized disease Rectal exam of internal genitalia External genitalia
What sex gland do we worry about causing disease in bulls
Seminal vesicles
What are some abnormalities you might find while palpating the seminal vesicles
Loss of lobules
Adhesions
One is larger than the other
What is the only frequently diagnosed disease of bovine accessory glands
Seminal vesiculitis
What infectious agents most commonly cause seminal vesiculitis
A. Pyogenes
Brucella abortus
H. Somni.
Mycobacterium
How to treat seminal vesiculitis
Can’t treat it
Won’t good enough antibiotic concentration to seminal vesicles
What are some abnormalities of the penis and prepuce
Fibropapilloma Penile abnormalities Hematoma Prolapsed prepuce Skin separation Laceration
When are the penile/preputial abnormalities seen?
After rectal probe is inserted to ejaculate the bull
What is fibropapilloma? Caused by? How to treat?
Common warts and papillomas on the penis
Caused by bovine papilloma virus
Can treat
No vaccines
What do you do with a bull with corkscrew penis
Cull the bull- won’t be able to perform coitus
What is a penile hematoma
A break in the tunica albuguinea of the penis with the escape of the blood from the corpus cavernosum into the surrounding tissues
What is a sequelae of penile hematoma?
Prolapsed prepuce
What is prolapse of the prepuce most common in? Why?
Bos indicus breeds because they have a pendulous prepuce
What can cause prolapse of the prepuce?
- Injury to preputial tissue with edema
- congenital preputial abnormality
How to treat preputial prolapse
Put in a sling, control infection, possibly surgery if it is a valuable bull
Why measure scrotal circumference?
It strongly correlates with testicular size and sperm production in bulls up to three years of age
*it is basically a measurement for parenchymal tissue (bigger= more seminiferous tubules)
How do bull testes hang?
Vertically
What is another benefit of measuring scrotal circumference?
Higher scrotal circumference means:
their daughters will reach puberty at an earlier age
Reduced probability that bull will suffer from testicular hypoplasia or degeneration
In litter bearing animals, means daughters will have more active ovaries (ovulate more follicles)
What does scrotal circumference have nothing to do with?
Testosterone and aggression
What is the minimum threshold for progressive motility?
30%
What stain is used for sperm?
Nigrosin-eosin
What is the minimum recommended threshold for sperm morphology to be normal spermatozoa?
70%
What are some sperm head defects in bulls?
Wrinkled acrosome Pyriform head Giant or small heads Nuclear vacuoles Diadim defect
What are some midpiece/tail defects in bulls
Dag defect Proximal or distal droplet (most common) Abaxial attachment Coiled or bent tail Stump tail
What does gossypol cause? Where is gossypol found
Gossypol is found in cottonseed product and causes segmented midpiece (impaired motility)
What are the classification for breeding potential?
Satisfactory
Unsatisfactory
Deferred
What is a satisfactory classification mean
Equals or surpasses all the minimum thresholds
30% progressive motility
70% normal sperm morphology
Good scrotal circumference
What are the minimum values for scrotal circumference
15 months: 30 cm
18 months: 31 cm
21 months: 32 cm
24 months: 33 cm
What does unsatisfactory mean?
Below one or more thresholds and unlikely to ever improve
What does deferred mean?
Bulls that are substandard but have the capability to improve
Commonly young bulls or bulls with heat stress
What are two veneral diseases to look for in bulls
Tritrichomonas foetus
Campylobacter fetus subspecies venerealis
