Breeding Soundness Exam

Question 1

what effect does high nutritional diets have during prepubertal period for male cows?

Answer 1

reduced the age of puberty and increased size and weight of testicles (we want them to hit puberty sooner so they can nut more for longer)

Question 2

what effect does high nutritional diets have DURING puberty for male cows?

Answer 2

fat deposition around testes, lamanitis, abnormal bone and cartilage growth lameness, etc. AKA dont feed them too much you DINK

Question 3

how do we decide to group bulls together?

Answer 3

depends on age, bull libido, fertility, environment (like size of pasture), feed and water availability

Question 4

what is a bull:cow ratio and what is the number we want?

Answer 4

essentially it’s how many cows can one bull shag

1:20-1:30 is most common. the older the bull, the more ladies he can handle

Question 5

when shopping for bulls, what are some things that help you decide which bull to buy?

Answer 5

can use expected progeny differences (EPDs)
certain breeds: hybrid vigour, breed traits
conformation
herd improvement vs terminal sires (a terminal sire is where no calves kept as replacement and all sold for meat)

ultimately it depends on the goals of your producer

Question 6

what is an expected progeny difference (EPD)? what major categories are you looking at?

Answer 6

an evaluation of an animal’s genetic merit, essentially you compare bulls to their breed standards

calving: calving ease
growth: weaning or yearling weight, milk
carcass: weight, marbling, rib eye area, fat thickness
maternal: docility, milk

Question 7

how to select for good birth weights based on EPDs?

Answer 7

normally for EPDs, we want a bigger number, but for birth weight, we want a small number because lower birth weights means less risk of dystocia

Question 8

what do CED and CEM stand for and how do they differ?

Answer 8

CED: calving ease direct, takes into account the birth weight of the calf
CEM: calving ease of the mother (does not take into account calf birth rate)

Question 9

for heifers, what EPD values do you want to select for when choosing your bull? How about for more mature cows?

Answer 9

for heifers: select for smaller birth weights (smaller numbers)

for mature: select for better carcass quality or bigger calves depending on what the producer wants

Question 10

why do we do BSE’s yearly?

Answer 10

because 20% of bulls are subfertile and the greatest econominc loss is with subfertile bulls and delayed conception. Every time we delay conception you lose weaning weight!

80% of cows are bred by 2 or more bulls so the lower fertile bulls are compensating for the more fertile bulls

Question 11

what are the 3 aspects of fertility?

Answer 11

good libido, physical soundness, good semen quality

Question 12

how do you test a bull’s libido? what are the downsides to doing this?

Answer 12

serving capacity=number of matings a bull is willing and able to perform in a test situation

downsides: not accurate in yearlings (they are shy and get scared when older bulls around), not welfare friendly for the females

Question 13

what are the 4 components of a breeding soundess exam?

Answer 13

physical exam
internal genitalia exam
external genitalia exam
semen evaluation

Question 14

why is body condition score important during your BSE PE?

Answer 14

too fat=can’t breed, it’s too hard, omg poor horny fat bulls
too skinny=no energy to breed omg poor starving bulls

Question 15

what BCS is ideal for bulls

Answer 15

3 or 4 out of 5

Question 16

why is leg conformation important to evaluate?

Answer 16

cows with bad comformation get culled sooner

Question 17

what general diseases do you want to look for on PE of bulls?

Answer 17

IBK, cancer eye, lumpy jaw, foot rot

Question 18

how to treat foot rot/interdigital necrobacillosis

Answer 18

systemic abs and NSAIDs

Question 19

what external genitalia structures do you need to examine?

Answer 19

scrotum, testes, epididimies, spermatic cord, penis, prepuce

Question 20

when palpating the testicles, what are you feeling for?

Answer 20

are the testes freely moveable? are they equal in size and consistency? are the epididymes turgid and prominent?

Question 21

scrotal dermatitis in bulls can be caused by

Answer 21

frost bite!

Question 22

proper way to measure scrotal circumference?

Answer 22

hold the scrotal neck with one hand and then use a measuring tape with the other hand! It should be fairly snug, but not too snug!!

Question 23

what is approx range of normal scrotal circumference in bulls?

Answer 23

for a 12 month old: the high 20s to low 30s range in cm

Question 24

larger scrotal circumference is associated with

Answer 24

greater testicular volume=greater sperm production

earlier onset of puberty in offspring

Question 25

for an internal genitalia exam what are we looking at?

Answer 25

vesicular glands, ampullae, inguinal rings

Question 26

what should normal ampullae, seminal vesciles, and inguinal canal feel like on rectal palpation

Answer 26

ampullae: 10-15cm long and 5-8cm in diameter

vesciles: 8-15cm long, 3-5cm long

inguinal canal: should feel like a slit on either side, 15-20cm ventral to the pelvic brim and 5-15cm lateral of midline

Question 27

what are 2 ways to do semen collection?

Answer 27

artificial vagina and electroejaculation

Question 28

what are the 2 broad categories of a semen evaluation

Answer 28

motility and morphology

Question 29

how do we evaluate semen motility (procedure)?

Answer 29

on a heated slide, put a drop of semen on the slide and look at 100x

OR can put a drop of semen on a slide and look at 250-500x mag and use a phase contrast microscope

Question 30

hoe do you evaluate semen morphology?

Answer 30

on a heated slide, put a drop of semen and drop of eosin nigrosin stain to mix and smear, then use oil immersion at 1000-1250x magnification

Question 31

describe the gross swirling semen motility scores and what they mean?

Answer 31

VG/very good: rapid dark swirls
G/good: slower dark swirls
F/fair: no swirls but individual cell motion
P/poor: little or no individual motion

Question 32

how do you measure PROGRESSIVE motile sperm?

Answer 32

need a special microscope, BUT it’s the gold standard and is more accurate.

we want more than 30% progressively motile sperm

Question 33

when evaluating semen morphology, what percent normal do we want?

Answer 33

more than 70% normal

Question 34

detached heads (no tails) are associated with…

Answer 34

defective development OR bulls following sexual rest

Question 35

upon doing a semen morpholohy examination, you find these. what are they and what does this indicate? Does this defect affect the sperm at all?

Answer 35

these are knobbed acrosomes

due to stress OR abnormal thermoregulation

these sperm cannot penetrate the zona pellucida of the egg

Question 36

what is the most commonly missed morphology defect and what does it indicate?

Answer 36

nuclear vacuole defect

if present in large numbers=envonrmental issues, stress, thermoreguation, dexamethasone, toxins

Question 37

a pyriform shaped sperm head indicates…

Answer 37

environmental heat stress

Question 38

what does this morphology abnormality indicate?

Answer 38

this is a Dag Defect

it is heritable or diet related

common in danish kersey bull

Question 39

what is this morphology abnormality indicate?

Answer 39

this is a cytoplasmic droplet

common in young bulls

proximal drops are worse than distal drops

Question 40

what is this defect and what does it indicate?

Answer 40

a bent tail

caused by improper handling of semen sample like hypotonic solution such as staining or cold shock, so you should recollect the bull and get a new sample to look at

Question 41

what is this defect and what does it indicate?

Answer 41

distal midpiece reflex

related to thermal insult of the testes

Question 42

if a bull has vesiculitis, what will you see on semen evaluation?

Answer 42

WBCs and RBCs under the microscope and barely any sperm

Question 43

what are the 4 “decisions” you can make at the end of a BSE?

Answer 43

satisfactory: meets the min requirements of motility and morphology, for scrotal circumference, and for PE

deferred: for younger bulls who need to be retested, or in mature bulls expected to make a recovery

questionable: give them time and re test them

unsatisfactory: not meeting minimum requirements

Question 44

t or f: a satisfactory potential guarantees fertility

Answer 44

false!

Question 45

transmission, clinical signs, and treatment/prevention of: trichomoniasis foetus

Answer 45

transmission: infected bull to a cow, back to a bull again via breeding
CS: early embryonic death, extended breeding seasons, and poor pregnancy rates
treatment/prevention: purchase virgin bulls who haven’t gotten infected via breeding an infected cow, testing and culling

Question 46

a producer calls you to ask how he can test his bulls for trichomoniasis, you tell him…

Answer 46

test 3 times 1 week apart to get highest sensitivity

either a pooled PCR (cheaper but if it’s positive you have to go hunting) or a culture (cannot differentiate from other trichomoniasis)

Question 47

what is the cause of vibrio? transmission? clinical signs? treatment prevention?

Answer 47

campylobacter fetus sp veneralis

transmission: survives in raw and processed bull semen. bulls are asymptomatic carriers. young bulls are resistant to the infection but older bulls become chronic carriers.

CS: vaginitis, cervicitis, irregular and delayed return to estrus, early embyronic death, abortion in late gestation

treatment: avoid contact with infected bulls and vaccine bulls

Question 48

how can you test your herd for vibrio?

Answer 48

preputial smegma, vaginal mucus, culture sample

best option is PCR, most sensitive and specific