12 Bull Breeding and Soundness Examination

30-60 days prior to breeding season

When do you do a breeding soundness exam in bulls?

1. thorough eval of the bull's history

2. physical exam

3. exam of the testes and measurement of scrotal circumference

4. detailed exam of genital tract via rectal palpation

5. collection/analysis of semen sample

List the components of the breeding soundness exam in the bull

a. bull history and physical exam

b. exam of genital tact via rectal palpation

d. exam of testes/measurement of scrotal circumference

e. collection/analysis of semen

Select the components of the breeding soundness exam in bulls:

a. bull history and physical exam

b. exam of genital tact via rectal palpation

c. exam of internal organs, ESPECIALLY rumen

d. exam of testes/measurement of scrotal circumference

e. collection/analysis of semen

f. exam of oral cavity and thorough diet testing

1. physical exam

2. minimum scrotal circumference

3. minimum progressive motility (30%)

4. minimum morphologically normal cells (70%)

Name the 4 parts of the breeding soundness exam that a bull must pass to be a satisfactory potential breeder

History

FEVER, breeding history, signalment, BCS, vaccination and deworming are all part of what component of the breeding soundness exam?

1. pampiniform plexus and testicular cords

2. testicles

3. epididymis

4. scrotum

What structures are you looking at when you examine the external genitalia of a bull in breeding soundness exam?

Physical exam

During this part of the breeding soundness exam, you look at the bulls ability to move with ease, detect females in estrus, mount, and complete breeding

Measuring scrotal circumference (at the widest part of the testicle)

What is this?

Scrotal circumference correlates with daily sperm output and age of his heifers at puberty (his daughters come into puberty younger with biggest testicles)

Why does scrotal circumference matter in bulls?

Rectal palpation

During this part of the breeding soundness exam, you evaluate internal genital structures and aids in semen collection by pre-stimulation for electroejaculation

Urethralis muscle, prostate, seminal vesicles, ampulla, inguinal rings

What internal genital structures are you feeling for on rectal palpation of a breeding soundness exam?

Prostate

What is 1?

Seminal vesicles

What is 2?

Ampulla

What is 3?

Ampulla - hotdog

What is 6? What will it feel like?

Seminal vesicles - grapes

What is 7? What will it feel like?

Prostate

What is 8?

Urethralis muscle

What is 9?

Urethralis muscle

This internal genitalia finding feels like a broomstick on the floor of the pelvis

Prostate

This internal genitalia finding feels like a ring on a giant's finger

Seminal vesicles (vesicular glands)

This internal genitalia finding is located cranioventral to the prostate, is lobulated, paired, symmetrical, and freely moveable in health

Ampulla

This internal genitalia finding is thick walled and tubular which are terminal dilations of the ductus deferens, lying midline between seminal vesicles

Inguinal rings

This internal genitalia finding is located just cranial and ventrolateral to the pelvic brim as slits in the abdominal oblique muscles

The difference between normal seminal vesicles (top) and asymmetric seminal vesicles (bottom)

What is this picture showing?

1. electroejaculation (most common)

2. manual massage (best for young bulls)

3. AV collection (bull stud operations)

Name the methods of semen collection for bulls

Electroejaculator probe

What is this?

Prepuce and external sheath, palpate penis through sheath

Name the things you are examining when doing external genitalia exam of a bull breeding soundness exam

Diphallus

What is this?

30%

You put a small amount of bull semen diluted with warm physiologic saline onto a 400x cover slip for breeding soundness exam. What is the MINIMUM acceptable progressive motility?

Minimum acceptable morphology is 70% (less than 20% can be head or mid-piece abnormalities)

You put a small amount of bull semen stained with eosin nigrosin stain and look at 1000x oil immersion level. What is the minimum acceptable percentage for normal morphology in a breeding soundness exam?

Fluid, nodules

Describe the characteristics of a healthy pampiniform plexus and testicular cords

Same size and shape, firm like a flexed forearm, temperature (NOT HOT), mobile within the scrotum

Describe the characteristics of healthy testicles

Size, shape consistent, no pain (granulomas will be FIRM)

Describe the characteristics of a healthy epididymis

No skin lesions, should be pendulous

Describe the characteristics of a healthy scrotum

Drop of stain on slide first, then semen drop near top of the slide; make 2-3 of them

How do you prepare a slide for looking at semen in a breeding soundness exam

Diff Quick

What do you stain the semen with if you suspect vesiculitis?

Head abnormalities, midpiece abnormalities, tail abnormalities, versus normal

When looking at morphology of semen, what things are you classifying?

Abaxial Tail Implantation and Distal Cytoplasmic Droplet

What two appearances of sperm where once considered abnormal but under the new BSE classifications are considered normal?

The sperm just to the right of the center of the image has an abaxial tail implantation = technically considered normal

What is this? Normal or abnormal sperm?

This sperm has a distal cytoplasmic droplet = technically considered normal (because the droplets are normally shed)

What is this? Normal or abnormal sperm?

Abnormal = coiled tail

What is this? Normal or abnormal sperm?

Abnormal = Coiled Tail

What is this? Normal or abnormal sperm?

Abnormal = "dag defect"

What is this? Normal or abnormal sperm?

Abnormal = thick midpiece

What is this? Normal or abnormal sperm?

Abnormal

What is this? Normal or abnormal sperm?

Abnormal = two tails

What is this? Normal or abnormal sperm?

Abnormal = proximal droplet

What is this? Normal or abnormal sperm?

Abnormal = coiled midpiece

What is this? Normal or abnormal sperm?

Abnormal = knobbed acrosome

What is this? Normal or abnormal sperm?

Abnormal = knobbed acrosome

What is this? Normal or abnormal sperm?

Abnormal = pyriform head

What is this? Normal or abnormal sperm?

Abnormal = pyriform head

What is this? Normal or abnormal sperm?

Abnormal = nuclear vacuoles

What is this? Normal or abnormal sperm?

Abnormal = detached head

What is this? Normal or abnormal sperm?

Abnormal = distal reflex

What is this? Normal or abnormal sperm?

Abnormal = Dag like defect

What is this? Normal or abnormal sperm?

Abnormal = dag like defect

What is this? Normal or abnormal sperm?

Abnormal = proximal droplet

What is this? Normal or abnormal sperm?

Distal droplet = technically considered normal

What is this? Normal or abnormal sperm?

Normal sperm

What is this? Normal or abnormal sperm?

Cratered head sperm = abnormal

What is this? Normal or abnormal sperm?

Genetics, toxins, nutrition, infectious disease, HEAT, STRESS

What may cause increased abnormalities of morphology of bull sperm?

Percentage of normal sperm is lowest 3 WEEKS post heat/stress and returns to normal by 6 weeks post insult

How long does heat and stress affect morphology of bull sperm?

COOLER

Sperm normally stays 4 degrees C *warmer/cooler* than the core body temperature due to the pampiniform plexus, scrotal fat, and fluid surrounding the testicles

Suppresses LH and FSH (dec. testosterone --> neg. impact on Sertoli cells that help sperm grow)

What hormones does stress affect that has a negative impact on the sperm and its morphology?

Test mating

This is not included in the routine bull breeding soundness exam but is good to do because it reveals penile deviations, evaluation of libido, and ability to make intromission

1. progressive motility over 30%

2. normal morphology over 70%

3. appropriate scrotal circumference based on age

4. no physical defects noted

What classifies a bull during a breeding soundness exam as SATIFACTORY

Re test in 60 days

What does it mean if you have a bull with a breeding soundness exam classified as "deferred"?

1. progressive motility under 30%

2. normal morphology under 70%

3. inappropriate scrotal circumference based on age

4. physical defects noted

What classifies a bull during a breeding soundness exam as UNSATISFACTORY

1. libido

2. doesn't ensure bull is highly fertile

3. doesn't ensure bulls are free of infectious agents in semen

You have done a semen evaluation for a bull breeding soundness exam. Motility and morphology are normal. This is all good, but what does it NOT measure?