Canine Breeding and Reproduction

Question 1

when is sexual maturity in dogs

Answer 1

-typically between 6 and 15 months
-first viable sperm production usually by 12 months
-varies breed by breed, smaller sooner

Question 2

how often fo dogs have a estrous cycle

Answer 2

-usually 2x per year
-basenji and dingo 1x per year
-wolves cycle 1x per year
-late spring and early summer months

Question 3

complete canine estrous cycle

Answer 3

-complete cycle takes 6 months in domestic dogs
-estrous semiannually
-estrus “heat”
-metestrus (diestrus)
-anestrus

Question 4

how can heat cycles vary

Answer 4

-in length
-when they get their first heat
-how often
-within breed

Question 5

things seen in different stages of heat cycle: proestrus

Answer 5

proestrus: ~9 days
-vulva swollen
-bloody discharge
-attracted to male but does not mate

Question 6

things seen in different stages of heat cycle: estrus

Answer 6

~9 days 4-13 days
-accepts male
-straw coloured discharge

Question 7

things seen in different stages of heat cycle: metestrous or diestrus

Answer 7

-non pregnant:
~90 days
-can have pseudo pregancy
-swelling goes down

-pregnant:
-pregnancy
-parturition 63 days from ovulation

Question 8

things seen in different stages of heat cycle: anestrus

Answer 8

-2-5 months
-sexual inactivity

Question 9

hormonal change of FSH

Answer 9

-goes up and then down during anestrus
-after its all the way down proestrus begins

Question 10

hormonal changes if LH

Answer 10

increases and drops at the beginning of estrus
-stimulating ovulation

Question 10

hormonal change if E2 (estradiol)

Answer 10

-present towards the end of anestrus
-continues to rise till end of proestrus then drops
-increases a little at the end of metestrus I
-drops soon after metestrus II

Question 11

hormonal changes of progesterone

Answer 11

-low amounts present in proestrus
-steadily increases through out estrus
-increases till end of metestrus I then drops
-goes down until metestrus II

Question 12

different cytology based off of the stage a dog is in

Answer 12

-rounded and hundreds of cells, with nucleus indicating anestrus
-nucleated and enucleated cells indicate proestrus
-cortified cells (square and flat) indicate estrus

Question 13

how long are dogs pregnant for

Answer 13

63 days

Question 14

determining the timing for mating

Answer 14

-male and female should be physically mature
-swelling of vulva
-bleeding
-hormone testing available
-vaginal smears to show cell shape

Question 15

what in in the blood tells if the female is ready to be mated

Answer 15

progesterone

Question 16

things seen in different stages of heat cycle: prolactin

Answer 16

-in pregnant dogs is present and starts to increase at the beginning of metestrus II
-drops right at the end

Question 17

natural copulation

Answer 17

-behaviour clues: frolicking, tail tucking, and tail flagging
-present hindquarters, tail to side
-tradition is that female goes to male
-they are territorial so male can get stresses

Question 18

stages of canine mating

Answer 18

-first stage coitus (1-2mins)
-the turn (2-5 seconds) first 2/3 of semen deposited at this point
-second stage coitus (5-45 mins) 1/3 of very rich semen deposited
-this is the tie, bulbus glandis engorges, constrictor vestibuli muscles of vagina contract
-successful tie should last 15-20 minuites

Question 19

artificial insemination

Answer 19

-chilled, not frozen semen
-AKC registration of pups required vet to collect and inseminate
-vaginal insemination possible
-success rate is variable
-above cervix increases success

Question 20

AI success rates

Answer 20

-for percent whelping and litter size
-highest success to lowest
-fresh, chilled, frozen-thawed
-Intra-uterine, vaginal

Question 21

selecting a mate

Answer 21

-inbreeding co efficient < 10%
-complement strengths and improve weaknesses
-genetics- disease, behaviour, appearance, temperament

Question 22

how often should dogs be bred

Answer 22

-skip a heat between whelping
-larger litter
-healthier pups
-improved longevity for bitch
-wild canids have one litter per year

Question 23

male reproduction problems

Answer 23

-frozen testicles (> or eq to 60 days loss of viable sperm)
-steroids (prednisone for allergies)
-brucellosis bacterial infection that renders a male sterile)
-cryptorchidism
-normal decent of testicles 7-10 days

Question 24

female reproductive problems

Answer 24

-tumors, cysts
-chromosomal abnormalities
-false pregnancy (prolacting, same as pregnant)
-60 days after estrus
-may lactate, gain weight
-may display nesting behaviour

Question 25

breeding and age

Answer 25

-males sperm count declines by 9 years
-females not bred by 5 may have greater risk of whelping problems
-most bitches retire around 6

Question 26

induced estrus

Answer 26

-one female in heat, causes heat cycles to begin in other females
-litters would be closer together then ideal in a kennel with multiple litter/year