Small Animal repro Flashcards
Explain anatomy of the canine/feline reproductive tract
- Vagina Body: Made of longitudinal folds which increase under oestrus due rising E2 levels → can be used as a guide to stage the oestrus cycle
- Male Dog:
Testes: Orientated horizontally, epididymis is dorsal
Penis: Os penis
Accessory Glands: Large prostate that is palpable via rectum - Male Cat:
Testes: Orientated horizontally/diagonally, epididymis is cranio-ventral
Describe the canine oestrus cycle
Type: mono-oestrus 1-3 cycles/year. except Basenjis, wolves, Tibetan mastiffs cycle once a year.
Cycle duration: 7 months (range 4-12)
Ovulation: Lasts 3 days 2d post LH
Puberty: 7-12 month (6-24 month)
Fertilisation: 48-72 hours
Fertility: Decreases from 4 years, lowered sig. beyond age of 8
Gestation: 57+-1d post D1 OR 65+-2d post LH OR 58-72d from a single mating
What the phases of oestrus in canines?
- Pro-Oestrus: 5-9d (2-25d), Bitch has swollen vulva & blood, E2 ↑ and peaks prior to oestrus
- Oestrus: 6-12d (2-21d): Bitch allows mating, E2 decreases and P4 increases towards the end
- Dioestrus: P4 is the dominant hormone, last in pregnant 57d from D1, non-pregnant 2-3m
- Anoestrus: P4 levels are low causes reproductive quiescence, (resting) lasts 4m (3-10m)
What are the effects of hormones in the oestrus cycle?
- Oestrogen:
o Oedema of the vulva & vaginal mucosal folds
o Thickening vaginal epithelium
o Bleeding from endometrium o ↑ P4 receptors on the uterus
o Development of endometrial glands & mammary ducts
o Attracts males - Progesterone:
o Stimulate further endometrial gland development & secretion
o Suppress contractility of uterus
o Closes cervix
o Suppress leukocyte response in uterus
o Get mated & keep pregnant
What are some unique features of the oestrus cycle?
- P4 ↑ before oestrus
- Standing heat via ↓ E2 & ↑ P4 (increasing oestrogen and decreasing progesterone).
Progesterone levels start to increase BEFORE ovulation. - Ovulation of primary oocytes: Not fertilisable immediately, must undergo meiosis (48-72hrs), to ber eady for fertilisation
How to monitor the oestrus cycle?
- Vulvar turgidity/consistency
Pro-oestrus: Turgid
LH Surge: Sudden drop in turgidity
Oestrus: Doughy
*Vaginal cytology tells you that the bitch is in oestrus, and marks the day that she enters dioestrus
*Vaginoscopy helps to decide when to breed the bitch during oestrus (shrunken angular, pale, dry phase - late oestrus)
- Vaginoscopy/Speculum:
Method: NO lube (sperm toxic), gentle twisting motions whilst avoiding the clit & urethra
1. Pro-Oestrus: Swollen, pink, moist vagina folds
2. Late Pro-Oestrus to Early Oestrus: ‘Shrinking Rounded’ Folds large but shrinking, becoming drier & paler, 2nd transverse folds appear
3. Early Oestrus: ‘Shrinking-Rounded’ Folds large but shrinking as oedema decreases due to E2↓, becoming pale/dry, primary & secondary folds still round
4. Mid-Oestrus: ‘Shrunken Angular’ Oedema almost completely gone, folds are small & becoming angular, is pale-pink/pale & dry
5. Late-Oestrus: ‘Shrunken angular’ Small angular folds, pale & dry
6. Very Late Oestrus: Folds are sharply angular but some crests are becoming rounded & pale with increasing pinkness via epithelial sloughing, malodourous cell-rich opaque discharge
7. Early Dioestrus: Folds are small, pink, moist and round, foul smelling brown discharge (+- White/bloody) for 2-5d, bitch may still be attractive for a few days
8. Dioestrus: Folds are small, round, pink, moist and ‘rosette-shaped’
9. Anoestrus: Same as Dioestrus - Vaginal Cytology:
Method: Moisten sterile cotton bud with saline inserted dorsally in the vestibule to access the cranial vagina through a speculum → twirl 360→ roll on a microscope slide & stain with diff-quik
Superficial Cell Index (SCl): Proportion (%) of superficial cells present on a smear
–> Oestrogen increases the number of layers of cells within the epithelium. Increases distance between most superficial layers and blood supply.
–> Can see which stage of the oestrus cycle
Cell Types:
Superficial Cells: Dead, dark-staining cells with a large angular cytoplasm & either no/pyknotic nucleus (Not vesicular cf. alive cells)
Intermediate Cells: Alive, vesicular living nucleus with clear outline, partly angular (Small) or angular (Large) cytoplasm
Parabasal Cells: Alive larger living nucleus, similar to intermediates but smaller & rounder
Basal Cells: Alive, largest vesicular nucleus, smaller & darker than parabasal cells
Phases:
Dioestrus & Anoestrus: SCI- Low <20%, RBC – No,
Neutrophils - +/- (Most in dioestrus), Debris - +++,
Bacteria - +++,
Thin layer of cells on slide
Pro-Oestrus: SCI – Rising 60-80%+,
RBC – Many sometimes but ↓ progressively,
Neutrophils – Some but progressively ↓, Debris – progressively ↓,
thin layer of cells on slide
Oestrus: SCI – 100% (All superficial), Debris – No (Clear),
RBC - +/-,
Neutrophils – NONE (Otherwise indicates infx/endometritis),
Cell layer progressively thickens with superficial cell rafts (Sheets of superficial cells) in the last 1-2d
(D1) First Day of Cytological Dioestrus: The first day where SCl drops by >20% with an ↑ of >10% intermediates/parabasal cells.
Marks the end of the fertile period
–> Stop further inseminations
- Behaviour Sx:
Tickle/rub the perirenal area between the anus and vulva
Reflexes (Tickle/Rub Perineal Region):
o Vulva reflex: Vulva lifts upwards
o Tail reflex: Deflects to one side
o Lordosis: Less useful, sometimes slight back arching - Hormonal Assays
1. LH: Snap test, not quantitative. Requires, 1-2 times daily, blood sampling to catch LH surge
2. Progesterone: Test every second day. LH surge coincides with a rise in progesterone above 6 nmol/L. Ovulation occurs around 16 nmol/L.
P4 rise above 30 nmol/L = confirms ovulation
*Aim to breed 4-7 day after LH surge using identified P4 (or LH)
*P4 value cannot indicate when it is too late to breed/D1
–> Only vaginal cytology can tell
Describe the Feline Oestrus Cycle
- Type: Seasonal polyoestrous (Summer) induced ovulation +- spontaneous, esp. in Orientals
- Puberty: 4-12m age
- Ovulation: 29-40hrs post coitus
- Oestrus: 7d
- Gestation: 66d (64-69d)
Phases
- Non-mating: E2 follicular phase for 1wk & interoestrus for 2wks (Low E2)
- Ovulation w/o Conception: LH surge in follicular phase → dioestrus (4-5wks) → ovarian inactivity (2wks)
Dx of Pregnancy
Diagnosis of pregnancy
- Abdominal Palpation: 15-30d
- US: >16d
- Radiographs: >40d
- Nipples Pinking: 2-4wks
How to approach breeding management?
- Ask owners to bring in bitch a few days after noticing vaginal bleeding
- Perform basic oestrus monitoring (OM), e.g, Reflexes, turgidity, vaginoscope, cytology
- Repeat OM every 2-4d initially; preferably 2d once LH surge until breeding/D1
- Add P4 (+-LH) as required
How to manage fresh semen via AI or natural breeding?
Fresh semen AI or natural breeding:
- Breed when enter the pale-dry-shrunken angular (100% SCI) phase, usually 4 days after LH surge
–> Oocytes 4-5 day prep for fertilisation + 2d ovulaion post LH = 4-5 window before D1 - 2-3 inseminations/matings done every second day, during the most fertile period (last 4 days of oestrus)
- Lifespan: 1 week
- Dose: > 150 million
Method for Fresh Semen AI:
- Check semen motility beforehand → carefully draw into warm pipette & syringe
- Insert pipette dorsally into vulva avoiding the clit/urethra to the fornix, as deep as possible
- Lift the bitches back legs and expel the semen → massage clit for 30s to encourage oxytocin
- Keep hindquarters elevated or 10m unless using TCI or Mavic catheter
What is a Mavic AI Catheter?
- Mimics the bulbus glandis of the dog penis
- Balloon is inflated following placement of catheter into vagina
- Sperm is passed through the catheter, followed by post-sperm fraction/semen extender. Injected slowly over 10 minutes
How to manage fresh chilled semen/frozen semen?
Fresh chilled Semen
Timing: 4-5d post LH surge
Frozen Semen
Lifespan: 24hrs once inseminated Timing: 5.5d post LH surge
Dose: Small dose 100 mil
Method:
- Using either a Norwegian pipette, surgical or using an endoscope to catheterise cervix (TCI)
- Inseminate directly into uterus instead of cranial vagina
What are important hormones in pregnancy?
- Progesterone – not specific for pregnancy
- Prolactin – increases throughout dioestrus, not specific
–? luteotrophe (maintains the CLs)
–> preparing for, and maintaining, lactation - Oestrogen – small rise during second half of gestation
- Relaxin – pregnancy specific – detectable from D21, rises through second half of gestation
Diagnosis:
- Abdominal palpation
- Radiography
- Ultrasound
- Hormone assays: Relaxin
How do you estimate gestation length?
Indications:
- When dealing with dystocia
- Managing a C-section or pregnancy termination
Whelping:
- 58 to 72 says from a single mating
- 63-67 days after the LH peak
- 56-58 days post D1
- Long fertile period due to longevity of sperm in the reproductive tract (7 days of fresh semen)
- ALSO 4 day fertilisation period at the end of oestrus
*11 days prior to D1 during which mating result in pregnancy
–> Range of when birth will be due to this
Estimating Gestation date:
- Number of days from mating to today
- Gestation length range from D1
- Further mating dates: Widens the window
Also use progesterone levels to predict:
- If p4 lower than 8.7 nmol/L: 48 hours
- If P4 < 3.18 nmol/L: 24 hours
- If P4 low, likely to be close to whelping
- If P4 high, unlikely to whelp within 12 hours
Other methods:
- Ultrasound measurements of amniotic sac, embryo/foetus
- Radiography
- Auscultation of foetal heartbeats: last 5 days gestation
- Relaxation of abdomen, preineal area and paracervical area
–> Abdomen changes from barrel shape to pear shape
–> Cervix becomes visible when paracervical area relaxes
- Mucoid discharge: Liquifaction of mucous plus: 4 weeks to 1 day prior to whelping
- Lactation: 2 weeks prior to whelping
- Rectal temperature may fall one degree witihin 24 hours to 36 hours of parturition. Not reliable
What are the stages of parturition?
- Stage I: onset of uterine contractions, relaxation of the cervix, ~ 6 – 12 hrs
- Stage II: full dilation of cervix to expulsion of final foetus (hrs)
- Stage III: expulsion of foetal membranes (usually follows each pup)
What is Dystocia?
- Maternal vs foetal causes
- Primary inertia: Failure to push
- Obstructive dystocia: Pushing is futile
Signs:
- Strong tenesmus (painful defecation) for 20-30 min without pup
- Weak intermittent tenesmus for more than 2-3 hours
- More than 4 hours between pups
- Green discharge before the birth of first pup
–> Placental separation: Oxygen supply may be compromised
- Abdominal discharges e.g. black, bloody, purulent, stinking
How to diagnose Dystocia
Abdominal radiographs:
- Number of foetuses present/left
- Gestation length
Ab US:
- Normal foetal heart rate: >220 beats per minute
- HR < 180 bpm: Getting nervous
- HR <150 bpm: Proceed to C-Section
Digital palpation
Vaginoscopy
- Identify foetal membranes = cervix dilated
- If dilated: C-section safe
What is primary inertia?
Is the inability of a dam to deliver normal sized foetus through a sufficient birth canal
Cause: Excess myometrium stretch, weak myometrium, HypoCa, Hypoglycaemia, anxiety
Treatment:
- C-section: After 3x oxytocin or prior
- Glucose supplement
- Oxytocin:
Timing: Wait 30-60m between doses, give only a max 3 doses before C-section
Contraindicated: High foetus no. as it may cause uterine tetany → foetal hypoxia or premature separation
–> Obstructive dystocia or if cervix still close it is also contraindicated - Ca supplement:
Total Ca may be normal but Ionised is low
Admin: Slow IV given to effect
Sings of Success (saturation): Stop if bradycardia, calm, nausea, vomiting, licking lips & uterine contractions
What is Obstructive Dystocia?
Pushing is futile → may cause 2nd inertia (Exhaustion)
Causes:
- Maternal: Small pelvic canal, Abnormal expulsion, abnormal uterus, or caudal repro tract
- Foetal: Increased size, abnormal presentation, abnormal development
Tx: C-section, resolve cause, e.g., correct malposition but is difficult due to small opening (Raising forequarters may help)
– hygiene is important
C-section:
- Short gestation length so do not cut until cervix is dilated on vaginoscopy
PPC < 6nmol/L considered safe
Estimated date for LH surge or D1 is major advantage
How to manage neonate resuscitation and care?
- Stretch the umbilical cord to encourage blood vessel closure → then cut 2cm away from ab wall
- Clear airways, assess heartbeat & rub vigorously with towel to stimulate RR
- If slow to breathe + HR present: Doxopram (1-2 drops sublingual/IM) & O2 or acupuncture philtrum/nasal philtrum to stimulate respiration
- Once breathing warm the pup (Do NOT do before as ↑ acidosis)
- Check for congenital abnormalities & weigh
Describe causes of Pregnancy Loss
Non-Infectious
Cause: Severe malnutrition, trauma, endocrinopathy, uterine insufficiency, exogenous drugs, genetic
Infectious
Bacterial:
- Brucella Canis:
–> Transmission: Ingestion, inhalation, venereal
–> CS: Often subclinical
Pathogenesis:
- Entry through the mucosa → regional LN → bacteraemia into the following areas
- Male genital tract: Infertility, epididymitis, testicular atrophy, orchitis
- Pregnant female: 3rd trimester abortion, infertility
- Reticuloendothelial System: Splenomegaly, lymphadenopathy, hepatitis
- Filters: Discospondylitis, paresis, uveitis, meningoencephalitis, arthritis, glomerulopathy
Diagnosis:
- Bacteria Culture: Difficult, done on chilled tissues
- Blood Culture
- Rose Bengal Test (RBT): More sensitive (Not species specific)
- Complement Fixation (CFT): More specific (Not species specific)
- Slide Agglutination: High sensitivity, low specificity → follow with AGID
Treatment:
- Not recommended due to potential relapse and human susceptibility
- Castration + Ab therapy (Minocycline, Aminoglycoside)
Control (Endemic): Ensure kennels disease-free, test animals prior to external breeding, quarantine
Brucella Suis
Incidence: Widespread in feral pig populations (QLD & NSW)
Transmission: Pig hunting or ingesting raw pig meat Zoonosis: Careful w/ Sx on hunting dogs
Dx & TX: Same as B. Canis
VIral
Canine alphaherpes virus-1
CS:
- Adults: Tracheobronchitis, vesicular lesions on vestibulum/vagina/prepuce
- Bitches: Late abortion, mummified foetus, still-birth, ↓ litter size
- Neonates (<2wks): Anorexia, ab pain, crying, mucosal haemorrhage, death <48rs
Pathology:
- Scattered haemorrhage in kidney
- Necrosis of liver & lungs
- Enlargement of spleen & LN’s
- Intranuclear inclusion bodies
Dx: No readily available tests in Aus
Tx: No effective Tx, experiments on temp >37 degrees suppressed replication
Control: Minimise stress! Isolate pregnant & lactating bitches, vaccination during oestrus & final week of gestation
What is the CEHMEP Complex?
Cystic endometrial hyperplasia, mucometra, endometritis, pyometra (CEHMEP)
CS: Infertility (CEHME)
Pathogenesis:
1. Oestrus: Oestridial causes development of endometrial glands & P4 receptors
2. Progesterone:
o Further secretion from endometrial glands → cystic changes
o Suppress motility of endometrium
o Closure of cervix
o ↓ Immune funct.
What are other conditions of pregnancy and the puerperium?
- Pregnancy Toxaemia
Incidence: Uncommon Cause: Inadequate nutrition, large litter
Dx: Ketonuria w/o glucosuria, hypoglycaemia, CS of depression & recumbency
Tx: IV dextrose, improved nutrition, severe cases may warrant OVH/induction/abortion - Metritis
Is inflammation of the endometrium and myometrium usually <1wk post whelping
PF: retained placenta/foetus, traumatic/unhygienic obstetrics, unhygienic environment
CS: Fever, malodourous red-brown discharge +- leukocytosis/leukopenia, shock, dehydration
Dx: No P4 present post-whelping (Ddx pyometra cf. has P4), Vagina cytology (Degenerate N, bacteria), Ab US & radiographs (Uterine size & presence of foetus)
Tx: Fluid therapy, broad spectrum Ab, ecbolic +- OVH (foetal remnants), dextrose supplement (Hypoglycaemia) but AVOID IU infusion
Uterine Prolapse
Incidence: Rare
Tx: Replace via laparotomy, OVH if traumatised/no longer breeding
–> Ovariohysterectomy
Px: Recurrence is uncommon
- Subinvolution of Placental Sites (SIPS)
Is bloody vulvar discharge lasting for >6 week after parturition but otherwise healthy
Incidence: Common, especially in young primiparous bitches
Pathogenesis: Abnormal persistence & invasion of endometrium by foetal trophoblasts causing erosion of maternal BV’s
Tx: None if healthy, resolve spontaneously at pro-oestrus, monitor anaemia/metritis (OVH)
Ddx: Oestrogenisation, vaginitis, metritis, neoplasia, haemorrhagic tendency
Px: Doesn’t recur, doesn’t affect future fertility - Hypocalcaemia AKA Milk Fever
Host: Usually small breed with a large litter of ~3wk pups
Cause: Pre-partum or during parturition as a cause of primary intertia
CS: ↑ Muscle tone, tremors, clonic spasms, dilated pupils, seizures, dry nose
Dx: Total Ca <7mg (Normal 9-11), ionised Ca <0.8mmol or <2.4mg
Tx: Calcium gluconate – admin slowly IV to effect, manage diet, ↓ suckling
PX: If results not dramatic post Ca rethink Dx
Ddx: Epilepsy, meningoencephalitis, poisoning (Coffee, 1080)
What is a pyometra?
Causes: E. Coli!!! Strep, Staph, Klebsiella, Proteus, Actinomyces, Pasteurella, etc.
PF: Repeated non-pregnant cycles, oestrogens, progesterone
Timing: Dioestrus!! 1-12wks post-oestrus
Cause: NOT from the male → from bitches’ poo
Hosts: Middle-age/old unspayed nulliparous/low parous, history of exogenous steroids
CS: Purulent vulvar discharge, non-specific signs of illness (ALWAYS think Pyo in non-specific signs in intact bitch)
Diagnosis:
- Vaginoscopy
- Cytology +- Culture
- Ab US
- Haematology: Severe leucocytosis w/ left shift (+- normal), Normocytic/chromic anaemia
- Serum: Hyperglobulinaemic, hypoalbuminaemia, pre-renal azotaemia, liver dysfunction
- Urinalysis: Low USG (ADH interference via endotoxin), renal casts +- Proteinuria/glucosuria
- Contra-indicated: Do NOT palpate abdomen (Uterine rupture)
Tx:
- Stabilise & OVH: Lavage after, take care w/ ligatures, tie off arteries early, open large
- Medical Tx:
Indication: <4yo, valuable breeder, systemically healthy
Methods: Similar to abortion induction, e.g., PGF2a, Aglepristone, Cabergoline +- Misoprostol (Cervix dilation), Oxytocin (Helps evacuate – only if cervix open & P4 at baseline)
Adjuvant: Combine with Broad spectrum Ab (Amoxycillin + Metronidazole)
Timing: Continue until uterus is normal on US, vagina discharge stops +- P4 reaches baseline
Post-op: Advise breeding on subsequent oestrus
What is Transmissible Venereal Tumour?
Transmission: During sex or sniffing/licking genitals, metastasis
Cause: ?Viral
Envi: Many free-roaming dogs in warm humid climates (NA)
Prevention: Strict biosecurity
CS: Tumours around penis/vagina/oral/nasal mucosa, pink/grey friable ‘cauliflower heads’ & discharge
Dx: Impression smear (Round cells), biopsy, response to vincristine
Tx:
- Chemotherapy: Vincristine (Doxorubicin), Treat weekly for 1-2 treatments post resolution of lesion
- Surgical resection
- Radiation: Small lesions
- Sterilise ASAP
What is Vaginitis?
Inflammation of vagina
CS: Vulvar discharge, frequent licking of vulva, attracts male dogs +- Dsy/Pollakiuria, concurrent dz
Cause: Usually bacterial (E. Coli, Strep, Pasteurella, Staph)
PF: Anatomical defects, foreign body, urinary tract disease
Juvenile Puppy Vaginitis
Host: <1yo, onset >8wks
Tx: Usually resolve after 1st/2nd oestrus cycle, Abfor severe cases, based on +ve culture of cranial vagina
Adult-Onset Vaginitis
Host: >1yo
Primary Vaginitis: Brucella canis (E), Canine herpes virus
Secondary: Urine pooling (Congenital abnormality), foreign body, Neoplasia, urinary tract disease (UTD), Urinary incontinence
Dx:
o Vaginoscopy: Hyperaemia, neoplasia, FB (foreign body)
o Cytology: Neutrophilia
o Culture: Bacteria is normal in vagina; Tx only if pure heavy culture
o Digital exam: Anatomical abnorm
o Urinalysis: Rule out UTI
Treat: Primary cause if seen, systemic antibiotics based on culture and sensitivity, low does E2 for spayed dogs, phenylpropanolamine if there is incontinence, surgery for anatomic defects
What is the vestibulovaginal abnormalities?
CS:
- Inability to breed naturally
- Chronic vaginitis
- Chronic urinary tract infection
- Dystocia
Diagnosis:
- Digital vaginal exam
- Vaginoscopy (speculum, endoscope)
- Contrast vaginography
Treatment:
- Manual dilation: for minor vaginal strictiures
- Incision of small septae +- OVH (decreased heritability)
What is vaginal hyperplasia and prolapse?
Is the protrusion of oedematous vaginal wall into the lumen +- through the vulvar lips
Cause: Associated with pro-oestrus rise in E2 conc +- Oestrus or E2 rise in pregnant dogs
Consequence: Often recurs (60-100%)
Grade 1: Swelling of Caudal vagina. Vagina cranial to urethral orifice → vestibule appears swollen
Grade 2: Similar to grade 1 but mass protrudes from vulva
Grade 3: Whole vaginal circumference protrudes from vulva (Donut)
Tx: Vaginal cytology to confirm prooestrus/oestrus if required
Protect until resolved (when ↓ E2),
–> Protect with E-Collar, keep clean and moist, confinement
Manual replacement of mass w/ purse-string around vulva. (Monitor for irritation)
Advise OVH (prevent recurrence and source of oestrogen)
+- P4, Surgical resection
Ddx: Vaginal neoplasia – usually older dogs, anywhere in vagina, doesn’t vary w/ cycle
What is Split Oestrus?
CS: Signs of pro-oestrus → subside (no ovulation) → 2nd pro-oestrus to oestrus 3-6wks later
Timing: Common at 1st oestrus (Puberty)
Tx: Don’t – can breed at 2nd pro-estrus
What is Cystic Ovarian Degeneration?
Incidence: Rare but increases with age
Size: 1-5cm
CS: Anoestrus (Non-functional follicular or P4 cysts), nymphomania (Rare – E2 secreting)
Dx: US, Ex-lap, steroid analysis, vaginal cytology, serum P4
Tx: OVH, Surgical drainage (needle Aspiration – laparotomy), Mechanical induce ovulation (GnRH, hCG, PGF2a – varied response, recurrence possible)
What is Pseudopregnancy?
Incidence: All bitches essentially pseudopregnant (Dioestrus)
Pathogenesis: Decline in P4 & increase of prolactin towards end of dioestrus
Cause: OVH during dioestrus, abrupt stop of P4 Tx, Antiprogesterone Tx
CS: Mammary development, lactation, nesting, mothering inanimate, weight gain
Tx: Resolves 1-3wks, prevent licking teats, Prolactin inhibitors: cabergoline (↓lactation), treat for galactostasis/mastitis
Contraindicated: Phenothiazine – increase prolactin & milk secretion
What is Ovarian Remnant Syndrome?
CS: Cyclic oestrus Signs post OVH (Vulvar swelling, discharge, stands to mount, attractive)
Cause: Residual tissue revascularises ovarian tissue OR ovarian tissue displaced to the in round/broad lig. in development
Dx: Cytology, Serum preogesterone (Post-oestrus Signs, presence of luteal tissue), Ab US/Ex-lap, rule out other Ddx
Ddx: Vaginitis, neoplasia, stump pyometra, exogenous E2, coagulopathy
Tx: Surgical removal – maybe easier in diostrus, bilateral remnants in 35% cases
What is Cryptorchidism?
Failure of tests to descend into scrotum
Complications: Retained testes have higher risk of neoplasia (sertoli cell tumour – E2 secretion causing feminisation) & torsion
Dx:
- Palpation
- US
- Testosterone/AMG assay
- Ex-lap
- Stimulation Test: Baseline testosterone sample → GnRH/hCG & Rx sample at 1, 4, 8 hrs
Management:
- Remove internal testes prior to scrotal testes; never leave internal testis behind
- hCG & GnRH
- Castration/Vasectomy
What is Orchitis and Epididymitis?
Causes: Infection from trauma (Bites), Secondary to prostatis/cystits, haematogenous infection
Pathogens: Most commonly bacterial (Staph, E. coli, Proteus) or brucella canis
CS: Acute painful swelling of scrotum, fever, hindlimb lameness, purulent prepuce discharge
Dx: Palpation, US, semen culture/evaluation, CBC, needle aspirate (Brucella serology)
Tx: Surgical removal
What is Paraphimosis?
Is the inability to retract penis back into sheath
Cause: Hair ring, abnormalities of prepuce, neoplasia, scars, os penis fx, balanoposthitis, in-rolling of prepuce
Tx: EMERGENCY, anti-inflam treatment, local irrigation, try return into prepuce by removing cause and retain with purse string
Chronic cases: Phallopexy (Cr.)
What is Agalactia?
Failure of mammary development or milk letdown
Tx: Phenothiazine sedatives e.g. (ACP): suppress dopamine, Oxytocin
What is Mastits?
CS: Pain, erythema & swelling of glands (Local or general) +- Pyrexia, Left shift neutrophilia
Pathogens: E. Coli, Strep, Staph
Dx: US (Abscessation), cytology of milk, haematology (WBC, RBC, Bacteria)
Hemorrhagic/purulent discharge from teat
Ddx: Inflammatory mammary adenocarcinoma – usually in older dogs
Prevention: Trim puppies’
toenails, keep whelping area clean
Tx:
- Encourage suckling (Unless purulent) or milk out
- Anti-inflam
- Hot/cold packs
- Ab: 1st line – cephalexin, amoxicillin-clavulanic acid → must consider puppies/distribution
- Gangrenous mastitis: May require Sx drainage, debridement and flushing
How to Prevent, postpone or suppress oestrus in bitches?
- Desexing: Ovariectomy +- OVH
Adv (In order): Prevent pregnancy, mammary neoplasia, pyometra, gonad/prostate size, sexual behaviour
Dis (In order): Urethra sphincter incontinence, Prostate neoplasia, obesity (diabetes mellitus, hypothyroidism)
No Effect on: Hip dysplasia (Bone density & ability to train) - Progestogens
MOA: Uncertain, likely negative feedback on hypothalamus (GnRH) & Pituitary (LH, FSH)
Admin: AVOID depot formulas
Timing: Safest in anoestrus prior to E2 increase (Potentiates P4 effects → pyometra)
Dis: Cystic endometrial hyperplasia! Pyometra! Benign/neoplastic mammary nodules, adrenocortical suppression, ↑ appetite/Wt. gain/behaviour change/skin changes, predisposes DM & Acromegaly
- Megestrol Acetate (Ovarid)
Timing: Postpone oestrus - start 1-2 wks prior to expected pro-oestrus,
To suppress oestrus once it has begun – <3d of pro-oestrus
Dis: Use during oestrus can ↑ side effects and pregnancy is still possible
CI (Contraindications): Existing/previous pyometra, mammary neoplasia, diabetes, liver dz, pregnancy - Medroxyprogesterone Acetate (Provera)
Admin: AVOID depot formulation unless scheduled OVH Timing: In anoestrus
Dis: Not recommended in dogs due to high side effects - Proligestone (Covinan)
Adv: Can be used for temporary or long-term postponement, less side effects of oestrus.
Timing: During anoestrus <30d of heat → repeat at 3m, 4m, then 5m thereafter
Dis: Small pyometra risk, delayed return to oestrus, permanent sterility +- Discoloured hair
CI: Avoid in animals destined for breeding
- Androgens
Drugs: Mibolerone, Testosterone Propionate
Role: Negative feedback on pituitary preventing release of LH & FSH → no ovulation
CI: Admin prior to puberty, pregnant animals, renal dz, hepatic dz
Dis: Clit enlargement, vaginitis, masculine foetuses, seborrhoea, aggravation or adenoma - GnRH Agonists
Drugs: Deslorelin acetate, Azagly-nafarelin
MOA: Binds to GnRH receptors in anterior Pituitary → may initially induce oestrus → eventual downregulation of LH & FSH → suppression of gonads (↓ Seminiferous tubules)
Dis: Not registered in bitch – only on males to induce sterility
Other Use: Benign prostatic hyperplasia, behaviour control, testing prior to surgical castration, incontinence in spayed bitches (After trying E2 & Phenylpropanolamine)
- Suprelorin
Doses: 4.7mg supresses male fertility for 6month, 9.4mg for min 12month
Timing: Takes 4-6 wks to become sterile
Adv: Few side effects, long-acting after 1x Tx
Dis: Cheaper to sterilise In long run, varied return to fertility
Indications for Pregnancy termination?
Indications: Unwanted female serve, unwanted male serve, conception in an obstetrics risk bitch
Methods:
- Ovariohysterectomy
Timing: Early in pregnancy – if done in late gestation give adequate fluids
- PGF2a (Lutalyse)
MOA: Causes luteolysis & uterine contractions
Timing: V effective 2nd ½ gestation but takes time as CL is relatively resistant
Admin: 25ug/kg first injection → 250ug/kg 2x daily for >4d until all are aborted
OR lower doses (30ug/kg) every 8hrs for >5d (Fewer side effects)
Alt.: Synth PG (Cloprostenol; lower dose rates, only after 30d gestation but some dislike
Adv: Cheap ‘
Dis: Frequent Tx may require hospitalisation, Side effects (subside within 60min – nausea, diarrhea, discomfort)
CI: Heart/resp disorders, systemic illness, non-verified pregnancy
- P4 Receptor Antagonist, e.g., Aglepristone (Alizine)
MOA: Has affinity for P4 receptors 3x that of natural progesterone.
No P4 = no pregnancy
Timing: From mating (Post-heat D1) - 45d
Admin: 2x doses, 24hrs apart
Adv: Fewer side effects than PG, can be used In cats
Dis: Expensive
Post-op: US >10d after to check success (>30d from mating) - Dopamine Agonist/Prolactin Inhibitor
MOA: Prolactin supports CL → lowering prolactin removes CL support
Drugs: Cabergolin (50% efficacy >40d), Bromocroptine similar
Adj: Combined with PGF2a (Cloprostenol)
Adv: No major adv, can be admin orally - Oestrogen
MOA: Prevent implantation by interfering with uterotubal function/transport
Timing: A few days within mating Dis: BM suppression, cystic endometrial hyperplasia, Pyometra, dyscrasia - Glucocorticoids*Not recommended but don’t give whilst preg
Dis: Difficult to induce abortion, high dose for prolonged periods required
Side effects: PD, PU, Polyphagia CI: Pregnancy
– Use low-dose, short acting formula for non-repro disorders in pregnant bitch
What is the preferred methods for terminating pregnancy?
- Bitch not Destined for Breeding: Spay
- Destined for Breeding & Mating was Seen: (If owner saw the mating)
a) Tx with Aglepristone ~1 wk post-mating → confirm non-pregnancy 1m post-mating OR
b) Wait until 1m post-mating and examine for pregnancy → if pregnant Tx w/ Aglepristone/PGF2a to induce abortion - Destined for Breeding & Mating not Seen:
Take a vaginal cytology to see if bitch was in oestrus (+- presence of sperm)
a) In oestrus: Follow point 2 b) Not in Oestrus: Confirm pregnancy 1m later
What are the indications of inducing oestrus in a bitch?
Indications: Delayed puberty, protracted anoestrus (Not drug related), Sync of ovulation for ET
Prerequisites: Must be healthy, >4m from last oestrus (Anoestrus, with baseline progesterone levels)
CI: Intersex, chromosome abnormalities, hypothyroidism, other systemic illness
Effective treatment:
- Cabergoline: Daily at the start of anoestrus util 3-8d into pro-oestrus (May take a m). Induce fertile oestrus after 1 month.
- Deslorelin Implant: Explore flare at the beginning of Tx ~10d insertion to see LH surge→ remove
- eCG/hCG: LH-like effects
How to control repro in dogs/cats (Summary)
Control of Repro in Dog: Castration, vasectomy, GnRH-agonist (superlorin), Intra-testicular injection of zinc Gluconate
Control of Repro in Cats
Pregnancy Termination: Rare. Usually OVH, otherwise PGF2a, Prolactin inhibitors, Aglepristone
Suppression of Oestrus
- hCG/GnRh/Cotton Bud: Induction of ovulation → oestrus returns ~6-7wks
- Progestogens: Risk the same as in a bitch, done during anoestrus/interoestrus
- Melatonin Implant: Induce seasonal anoestrus; not in aus
Oestrus Induction: eCG + FSH, Prolactin inhibitors
