Uterus is between bladder and colon

The time when reproduction first becomes possible. 

is variable, ranging from 5-24 months, usually around 6 mo. 

Large and giant breeds mature more slowly

General physical signs: vulva and mammary enlargement

ovarian cycles 

regularly occuring periods during which the bitch is sexually active and receptive , with periods in between where there is no activity. 

one oestrous cycle per reproductive phase ( cf. cats) 

every 6 mo. on average

influenced by various factors including stress, disease, age, breed, social factors

No menopause 

pro-oestrus: 7-10 days ( range 4-14)

oestrus: 7-10 days ( range 5-15)

metoestrus: 63 days ( same length as pregnancy)

anoestrus: 3-4 months. 

in season during pro-oestrus and oestrus ( 2-3 wks) every 6ish mo. 

behavioural changes in oestrus initiated by rising levels of oestrogens but full expression and peak fertility requires oestrogen withdrawl in presence of progesterone. 

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Prolactin is luteotrophic and maintains progesterone levels days 25-50 by feeding the CL

- initiates mammary development, milk production and behavioural changes of pregnancy ex. nesting

- You might use prolactin inhibitors to treat false pregnancies. 

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Hormones: oestrogen increases from follicles in ovary

Physical: vulva turgid swelling, thin bloody discharge

Behaviour: may roam, flirting, but will not accept dogs 

Hormones: Oestrogen in decline, progesterone rising

Physical: vulva softer, discharge thicker, straw coloured

Behavioural: stands for male dog, sideways tail deflection 

Luteal phase

high levels of progesterone

same length as pregnancy-63 days

This is the time when false pregnancies occur 

no reproductive tract activity

no attraction to male dogs

3-4 mo. 

5-9 mo. 

usually begins in spring after birth

Oestrus depends on daylight

seasonally polyoestrous- they repeatedly cycle throughout Spring,Summer, early Autumn( unless pregnant) 

induced ovulation- spines

Polytocous 

When are Queens in season?

why might that be a problem?

every 2-3 wks. 

problem for spaying

less physical signs, more behavioural signs

affectionate, rolling, crouching, vocalising

coital stimulation causes LH surge and ovulation c.24 hours later 

Non pregnant, ovulated queens have shorter duration of elevated progesterone 

6-12 mo. 

Testicles in scrotum at birth 

if testicles not there by 12 weeks, very unlikely to descend- surgery - often get stopped in inguinal region on way down. 

Spay before first season: zero risk mammary cancer in later life but greater risk of urinary incontinence

Spay after first season, before second: apparently risk for urinary incontinence reduced 

Bitch left with dog for few days

minimal human intervention

Mating, tie ( dog steps off bitchs back and turns around-not necessary for fertile mating) , post coital 

Queen goes to tom in planned breeding, courtship of much vocalising, queen crouches, hind quarters raised 

Mating is quick, tom bites scruff, stimulation by penis, then queen licks and rolls, pair stay together

>2 yrs of age

- 3rd oestrus

< 8 yrs of age

When physically and temperamentally mature 

may breed from 6 mo. 

Planned breeding at 18 mo. 

depends on dog

4 wks: spheres

7 wks: foetuses

alot easier in cats 

6 wks- skeletons

single exposure okay

can detect foetal death in utero 

4 wks in bitch

placenta derived

ex. relaxin assay 

nest making

milk oozes

temp drop - 12-14 hours before birth- 0.5-1.0- falls at stage 1 labour , rises again at start stage 2 labour 

cats tend to disappear 

Restless

panting , agitated, wining - dogs

washing, vocalising- cats 

can last 6-12 hours

active abdominal straining

temp rises again

clear foetal fluids passed when allantochorion ( first water bag ruptures-bitch often licks fluid 

- lateral recumbancy, usually a neonate within 30 min of strong contractions

weak ones for 2-4 hrs considered abnormal

Stage 2 as a whole lasts up to 12 hrs and rarely up to 24 hr. 

see foetus in amniotic sac/membrane- second water bag

bitch often nibbles and breaks it open as well as umbilical cord - may need assistance for weak and ammature bitches 

1. mistake stage 1 for stage 2

2. interfere too much

3. havent prepared themselves

4. dont bring bitch to vet- upsets her more. 

abnormal birth

need a good repro history 

observe behaviour, take temp, feel abdomen, vag exam- are birth fluids present, obvious obstruction? 

Cervix cranial in bitches: if can feel pup in canal, vaginal delivery usually possible 

illness

obesity

breed

temperment/psychological

previous trauma to pelvis or abdominal wall

uterine inertia 

commonest cause 

Primary and Secondary 

uterus doesnt contract

Causes: 

1. single pup fails to stimulate myometrium or larger litters causes myometrial desensitisation by over stimulation

2. weakness in dam or prolonged parturition/dystokia

3. inherited

weak Stage 2 or Stage 2 starts then stops and nothign happens despite more pups are present in the uterus. 

might be a bitch with an enormous litter but worn out from straining 

1. for mild cases- gentle exercise 

2. Oxytocin +/- calcium if no obstructive dystokia- oxytocin stimulates myometrium to contract by increasing ca uptake. can be repeated but not excessive 

3. if obstructive-sort out, might need C section 

monitor ECG or atleast auscultate heart frequently, if bradycardia develops stop giving it. 

Have Iv. catheter placed and give infusion of saline or lactated ringers solution throughout this. 

basically wont fit

may be maternal problem like pelvica canal post trauma 

Uterine inertia and no luck with oxytocin 

obstructive dystokia

pelvic narrowing 

foetal death

sick dam

certain dog breeds