Lab quiz 6

Question 1

Breeding soundness exam purpose

Answer 1

• is to breed genetically superior, healthy males

- after BSE is complete the male is classified as satisfactory, questionable or unsatisfactory

Question 2

Three most commonly used methods of semen collection in animal agriculture

Answer 2

1. Artificial Vagina (neuroendocrine response)
2. Digit Manipulation (neuroendocrine response)
3. Electrojaculation (neural response)

Question 3

Behavior in semen collection

Answer 3

• Vocalization
• Teaser or stimulus
• Flehmen response
• Salivation due to pheromones
• Touch such as rooting, flanking, touching vulva
• Stimulus to ejaculate
• > Pressure and Temperature

Question 4

Count Sperm in a hemocytometer

Answer 4

1. Count number of sperm in 5 chambers and do the same for the other chamber
2. find the mean of the two totals and multiply the mean by 5 (bc really 25 in each chamber)
3. Multiply the mean obtained by 10,000 to obtain the number of cells per ml of diluted sample
4. Multiply that number by the dilution factor

Question 5

Three pieces of equipment needed for electroejaculation

Answer 5

1. The electrojaculator itself is a power supply with rheostats to control the amplitude of the delivered current and lots of circuitry to prevent accidental electrocution
2. a collection tube, usually attached to a latex rubber cone in which to collect the semen
3. the pulses of current are applied through a electrojaculator probe
   - probe is inserted into the rectum such that the electrodes lie within the pelvic cavity

Question 6

Phantom collection types

Answer 6

• neuroendocrine
  1. Artificial vagina
• high quality and high concentration
  2. Gloved hand techniques
• boars

Question 7

Gross appearance

Answer 7

• color and opaqueness

Question 8

Factors Affecting sperm

Answer 8

• temperature
• pH
• osmotic pressure
• oxygen tension
• toxins
• sunlight

Question 9

Digital Manipulation

Answer 9

• some species are stimulated to ejaculate by applying pressure and massaging the penis
• a large cup or director cone attached to a collection tube can be slipped over the penis to facilitate harvesting the semen
• commonly used for pigs, dogs and poultry
• additional type of digital manipulation in bulls involves stroking the ampullae and prostate gland through the wall of the rectum once the bull is restrained and slightly sedated
• presence of a female in estrus to arouse the male and a phantom to mount are both helpful

Question 10

Electroejaculation

Answer 10

• neural response, lower quality collection
• applying a series of short, low-voltage pulses of current to the pelvic nerves which are involved in the ejaculatory response
• can be used with almost any mammal
• only technique useful for collecting semen from wild animals, in which case the male is anesthetized prior to the procedure
• another advantage is that it does not require a mount animal and can be applied in the field using a battery-powered unit
• with bulls, samples collected using an electrojaculator usually have larger volume and lower number of sperm

Question 11

total sperm

Answer 11

• multiply concentration by ejaculate volume

Question 12

Visual Exam

Answer 12

1. Age
2. General Health
   - body condition score
   - lameness/feet
   - parasites
   - disease symptoms
   - libido

Question 13

Physical Exam

Answer 13

1. Palpate the testes
   - firmness, no lumps, epididymis feels normal and unobstructed
2. Check the penis
3. Internal structures such as ampulla and prostate are evaluated via rectal palpation (less common)
4. Measure the scrotum

Question 14

Motility

Answer 14

• the percentage of sperm that are progressively motile

- progressively motile sperm swims briskly forward in a relatively straight line, as opposed to moving in circles

Question 15

Morphology

Answer 15

• the percentage of sperm with normal shape and size

Question 16

Artificial Vagina

Answer 16

• phantom collection, neuroendocrine
• high quality and high concentration
• used to collect semen from cattle, horses, sheep, goats, rabbits and cats
• uses thermal and mechanical stimulation to trigger ejaculation
• made of tube with a rubber lining which holds warm water to provide temperature and add pressure
• lubricated inner liner is added just before use
• male is allowed to thrust into it
• male will often mount a phantom female, or a trained steer

Question 17

Semen Evaluation

Answer 17

1. Quantity
   - volume
   - concentration
   - total sperm
2. Quality
   - gross appearance
   - motility
   - morphology

Question 18

Volume

Answer 18

• the amount of ejaculation present

Question 19

Three parts of a Breeding Soundness Exam

Answer 19

1. Physical Exam
2. Visual Exam
3. Semen Evaluation

Question 20

Concentration

Answer 20

• how many sperm are present per mL of ejaculate
• most common means of determining sperm concentration is to count the sperm under a microscope with a hemocytometer
• hemocytometer is a glass slide onto which a precision grid has been etched
• can also count sperm using a spectrophotometer if a standard curve has previously been determined for similar samples

Question 21

What decides what method to use?

Answer 21

• the method is dependent on the species of the male and his deposition