Canine Breeding Management Flashcards
What is the first stepping stone in breeding management in canines?
Identify 1st day of vulvar discharge and start counting until day 18.
What is the second stepping stone in breeding management in canines?
Start 3-4 days after proestrus starts or when vaginal cornification (superficial cells) make up 50% of the cells to perform diagnostic blood work.
What is the third stepping stone in breeding management of canines?
Identify 1st day of standing estrus (Day 9)
When does LH peak in the dog?
24-48 hours into estrus
What causes the LH peak in dogs?
Estrogen peak during proestrus
Does LH have a short or long peak duration in dogs?
Very short peak duration
How often should LH be assayed in order to detect the peak rise in dogs?
Daily
When does ovulation occur in the dog?
When is this in relation to estrus?
- 24-48 hours after the LH surge
- Day 3-4 of estrus
About how long does ovulation take to complete in the dog?
About 24 hours
What is ovulated in the dog?
Primary oocyte (2N)
What has to occur after ovulation in a dog in order for fertilization to occur?
Primary oocyte (2N) must go through further meiotic division to a secondary oocyte (1N)
How long does it take for a primary oocyte to divide to a secondary oocyte in the dog?
2-3 days
How long is the secondary oocyte viable for in the dog?
3-4 days
What is the modern standard for breeding management used for assessing when to breed in the dog?
Progesterone (P4)
When should progesterone samples be taken in the dog?
Every other day (M-W-F)
An initial rise in P4 coincides with what?
LH peak
A progesterone level of what coincides with the LH peak?
2 ng/mL
A progesterone level of what coincides with ovulation starting?
5 ng/mL
Ovulation can be confirmed when progesterone is at what level?
Greater than 15 ng/mL
What happens to progesterone levels post-ovulation?
Become elevated and stay elevated
A rise in progesterone of 3 ng/mL in 24 hours coincides with what event?
Ovulation
Failure to confirm ovulation can lead to what 3 results?
- Conception failure
- Small litter
- Inaccurate due date determination
When should a dog be bred after P4 levels have reached 5 ng indicating ovulation if dealing with natural or shipped semen?
48-96 hours later
If using frozen semen, when should a dog be bred after P4 levels reach 5 ng?
72 hours
How long do embryos remain in the oviduct after ovulation?
9-10 days after ovulation
Embryos enter the uterus as what?
Late morula or early blastocyst
How long are canine oocytes good for post-ovulation?
Up to 108 hours
When is the fertile period in relation to ovulation?
-5 to +5 days
When is the fertilization period in relation to ovulation?
+2 to +5 days
When is the peak fertility time in relation to ovulation?
-1 to +4
When is the preferred time for natural service or fresh insemination in relation to ovulation?
0 to +4
When is the preferred time for frozen semen insemination or breeding where semen quality is not optimal in relation to ovulation?
+2 to +4
If the availability of the male and female is unlimited, when should breeding take place?
Every 2-3 days until female is no longer standing
How long can canine spermatozoa be good for in the genital tract of the female with natural cover?
Up to 6 days
There are higher conception rates and larger litter sizes with what type of breeding method?
Natural breeding
What is an assay that comes in an in-house kit that can be used in conjunction with a progesterone assay?
LH assay
Which is more definitive, an LH assay or a progesterone assay?
LH assay
What is a disadvantage to using an LH assay?
Must take daily blood samples
Gestation length in the dogs is defined as how many days?
63 days
Why do spayed animals have a high LH?
No negative feedback
What corresponds to the LH peak?
Initial rise in P4
When should be female be bred in relation the LH peak?
4 to 6 days after the LH peak
A male should have what value of progressively motile sperm for breeding?
200 x 10^6
Normal sperm morphology should be what percentage in the male used for breeding?
80%
Sperm motility should be what percent in the male dog used for breeding?
80%
A male dog to be used for breeding should be negative for what bacteria?
Brucella canis
What are 2 tools that can be used for measuring scrotal width?
- US
- Calipers
Be careful not to include what when measuring the testes?
Epididymis
What else should be evaluated other than scrotal width?
Symmetry
What are 3 possible means of semen collection in the dog?
- Manual stimulation and ejaculation
- Chemical ejaculation
- Electro-ejaculation
What is the most commonly used method for semen collection in the dog?
Manual stimulation and ejaculation
What is a method of semen collection that can be used in conjunction with manual stimulation?
Chemical ejaculation
Which method of semen collection may increase spermatozoa numbers?
Chemical ejaculation
What type of semen collection method requires general anesthesia?
Electro-ejaculation
What type of semen collection method may have urine contamination?
Electro-ejaculation
Where should the hand of the collector be placed with manual collection?
Caudal to the bulbous glandis
How many fractions does canine sperm have?
What are they?
- 3
- Pre-sperm, sperm rich, prostatic portion
How many sperm may be collected per ejaculate with manual collection?
300 million to 2 billion
How much oxytocin is given for chemical ejaculation and when?
- 5 IU SQ or IM
- 5-10 minutes prior to manual stimulation
How much prostaglandin F2a is given for chemical ejaculation and when?
- 0.1 mg/kg SQ or IM
- 15 minutes prior to manual stimulation
Why are oxytocin and prostaglandin F2a used for chemical ejaculation?
The myofibril cells of the epididymal duct are smooth muscle cells so these cells may respond to them.
What is the volume range for fraction 1 in mL?
Fraction 2?
Fraction 3?
- 0.5-5
- 1-4
- 1-80
What color typically is fraction 1?
Fraction 2?
Fraction 3?
- Clear
- Opalescent
- Clear
Which fraction of ejaculate is the sperm-rich fraction?
Fraction 2
What is the breeding dose of spermatozoa for the dog?
200 x 10^6 spermatozoa
What are the 3 groups of morphology sperm can be assigned to?
- Normal
- Primary abnormality
- Secondary abnormality
A fertile dog should be greater than what percentage morphologically normal?
Greater than 80%
What volume of semen is typically used for AI in a dog?
2 to 4 mL with 200 x 10^6 motile normal spermatozoa
What must be avoided when using a catheter for AI?
Going into the bladder
Canine semen should be extended in what ratio with commercial extender?
When should this be done?
- 1:1 to 1:4
- After centrifugation to remove excess fluids
How is canine semen usually frozen?
On dry ice in pellets or straws
The average dog may fill how many pellets per dose?
How many doses per ejaculate?
- 10-12 pellets per dose
- 3+ doses per ejaculate
How are frozen semen pellets thawed?
In warm extender
How much semen is frozen if a straw is used?
100 x 10 ^6 sperm per 0.5 mL straw
A dose for frozen semen should be what per insemination?
About 150 x 10^6 motile sperm per insemination
What are 2 methods for using AI with frozen semen?
- Trans-cervical
- Surgical method
Where should frozen semen be placed in the female with AI?
Uterine body
Where is the external cervical opening located?
Cranial ventral portion of the dorsal vaginal fold
If vaginal strictures or bands are present in the female, where do they tend to be?
Around the vestibulo-vaginal area
What might be necessary if a female has vaginal strictures or bands?
- AI
- C-section
Are vaginal strictures or bands considered a heritable trait or a developmental defect?
No
What is the term used for when 2 males breed the same female during a single estrus?
Does this happen in the dog?
- Superfecundation
- Yes
What is the term for when a female may be bred and get pregnant and then do through another receptive period (different estrus) and get pregnant again?
Does this happen in the dog?
- Superfetation
- No
