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130.e2 Breeding Management (Dog)

Breeding Management (Dog) Bonus Material Client Education
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• Perineal stimulation results in lateral devia-
BASIC INFORMATION
tion of the tail (“flagging”), elevation of the development of the squamous epithelium
and/or the vaginal cytology contains 100%
Definition vulva, and lordosis. superficial cells.
Diagnostic and treatment approaches that ■ Blood sample should be centrifuged
optimize a bitch’s reproductive performance Etiology and Pathophysiology immediately, or if not possible, refrig-
• Developing follicles secrete estradiol initially eration should be delayed 2 hours.
Synonyms (proestrus), followed by progesterone after ○ The day of LH surge (day 0) is the day
Breeding timing, estrus monitoring, ovulation the LH surge has occurred (estrus). on which serum progesterone concentra-
timing • Follicles ovulate 2 days after the LH surge, tion rises to above double the baseline
and oocytes are fertile another 2 days later. value. This is usually in the range of
Epidemiology • Oocytes remain fertile for 4 days. 1.5-3 ng/mL.
SPECIES, AGE, SEX • Breeding should occur between 3 and 8 days ○ Ovulation occurs during the rapid rise in
Dogs, postpubertal, female after the LH surge. progesterone, usually in the range of
5-10 ng/mL.
GENETICS, BREED PREDISPOSITION DIAGNOSIS ○ Progesterone can be measured by
• Breeding animals should be tested for heri- laboratory assays (radioimmunoassay or
table disorders important to the breed; Diagnostic Overview chemiluminescence) or by patient-side
> 400 genetic diseases have been identified For optimal timing of breeding, determine the semiquantitative ELISA assay.
in dogs. day of the preovulatory LH surge by detecting • B. canis testing is essential.
• In brachycephalic breeds or other bitches the first day on which serum progesterone
requiring an elective caesarean section, the concentration rises to become double the Advanced or Confirmatory Testing
caesarean section can be safely scheduled 64 baseline value (usually 1.5-3 ng/mL) or by • Vaginoscopy
days after the luteinizing hormone (LH) measuring serum LH concentrations directly. ○ Start 0 to 5 days after onset of vaginal
surge. Additional value may be found in vaginal bleeding; continue q 48h to monitor
cytology and vaginoscopy, both of which are estrogenization of the vaginal mucosa.
RISK FACTORS inexpensive, provide immediate results, and ○ Tubular Plexiglas speculum, 10-20 mm
• Advanced age of dam and/or sire may be performed on site but are less accurate inner diameter, 15-25 cm long
• Use of cooled or frozen semen; semen with than hormone assays. A typical protocol for a ○ Maximal development of the squamous
limited availability bitch whose signs of estrus are subtle involves epithelium (evident as paleness) and
• Dam’s or sire’s history of subfertility daily vaginoscopy or vaginal cytology until edema (evident as swollen, rounded folds)
• Degenerative and/or infectious conditions characteristic changes of early estrus are noted, of the vaginal mucosa coincides with peak
within the reproductive tract at which time serum progesterone is measured estradiol concentrations, just before LH
q 24-48h. surge.
CONTAGION AND ZOONOSIS ○ As estradiol declines, the edema resolves
Brucella canis Differential Diagnosis and the vaginal mucosa appears wrinkled
• Persistence of estrous behavior: granulosa or crenulated. Crenulation of the vaginal
GEOGRAPHY AND SEASONALITY cell tumor, endocrine-secreting anovulatory mucosa is an indirect indication that the
Bitches cycle at any time of the year (except follicle(s) bitch has had an LH surge and is near or
basenji: late summer/early fall). • Discharge from an open pyometra within her fertile period.
• Vaginal or uterine trauma resulting in • Serum LH concentration
ASSOCIATED DISORDERS bleeding ○ Commercial kits are available for semi-
Estrus induction, artificial insemination, quantitative assessment of serum LH
pregnancy diagnosis, elective cesarean section Initial Database concentrations in a convenient snap test
timing • Vaginal cytologic evaluation: (Witness LH, Zoetis).
○ Start 0 to 5 days after the onset of vaginal ○ Once- or twice-daily testing is required;
Clinical Presentation bleeding and continue q 48h to monitor LH concentrations remain elevated only
DISEASE FORMS/SUBTYPES estrogenization of the vaginal mucosa. for 18-24 hours.
Breeding management used may vary depending ○ Use a cotton swab moistened with saline
on the type of semen used and route of or a cytobrush to reach through a vaginal TREATMENT
insemination planned for the breeding. speculum for collection of cells from
cranial vagina. Treatment Overview
HISTORY, CHIEF COMPLAINT ○ During estrus, the vaginal cytology will Proactive strategies help to optimize efficacy
Owner desires litter from dam and wants to contain 100% superficial cells (cornified; of breeding.
maximize fertility and fecundity. large, angular, often with folded edges),
many of which still have nuclear remnants Acute General Treatment
PHYSICAL EXAM FINDINGS or pyknotic nuclei. • Breeding strategies
Physical exam should be unremarkable. Pro- ○ Presence of 50% or more cornified cells ○ Natural service, fresh or shipped (cooled)
cedures for a thorough reproductive evaluation can be used as the threshold for begin- semen artificial insemination
are outlined in Breeding Soundness Exam: ning measurement of serum progesterone ■ Breed on days 4 and 6 after LH surge.
Female Dog (p. 1070). Overt signs of estrus levels. ■ Inseminate vaginally, using a 5-mm-
should be evident: • Serum progesterone concentration thick plastic pipette that is advanced
• Swollen, edematous vulva ○ Start determining serum progesterone to the caudal end of the cervix (confirm
• Serosanguineous vaginal discharge concentration after there is maximal placement by abdominal palpation).

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