Canis ISSN: 2398-2942

Pregnancy termination

Contributor(s): Autumn P Davidson, Prof Gary England, Carlos Pinto

Introduction

  • Bitches that are misbred can undergo elective termination of pregnancy without negative impact on future reproductive potential.
  • Very commonly the involved sire and dam are of different breeds; and often times the bitches are too young (peripubertal age/first estrus).
  • Unwanted pregnancies contribute to dog overpopulation.

Uses

  • Elective termination of unwanted pregnancies eliminate the surplus of puppies for adoption.
  • Elective termination in young immature bitches allows them to complete their physical growth.
  • Pharmacological intervention is indicated for bitches of valuable breeding potential that would not benefit from ovariectomy or ovariohysterectomy.

technique

  • To utilize a pharmcological protocol that induces luteolysis or remove luteotrophic support. In the dog, prolactin and the luteinizing hormone are luteotrophic hormones.
  • For either regime, the efficacy is increased when pregnancy termination commences later than 25 days after ovulation.
  • Such later treatments, whilst more efficacious, are most likely to result in abortion of fetal material (in cases of very late abortion, the fetuses may be alive at the time of expulsion).
  • Treatments commencing before or by 30 days after ovulation are most likely to result in pregnancy termination by resorption, that may or not be accompanied by mild vulvar discharge.
  • Administration of PGF2alpha SC and misoprostol (Prostaglandin E; PGE) Misoprostol intravaginally.
  • Two types of luteolytic prostaglandin F2alpha: the natural PGF2alpha dinoprost tromethamine (Lutalyse®) and the synthetic PGF2alpha cloprostenol (Estrumate®).
  • Several commercial preparations of prostaglandin E are available; both PGE1 and PGE2 are available. PGE1 preparations are significantly less expensive than PGE2 products. Misoprostol (PGE1) has been shown to successfully induce pregnancy termination, especially when used concomitantly with PGF2alpha administration.
  • Combination therapy shortens the period of treatment time as compared to the use of PGF2alpha alone.
  • Lochia noted after a mean of 2.5 days of treatment, initiation of abortion after a mean of 3.5 days and completion of abortion after a mean of 5 days.
  • Administration of a combination of cabergoline and PGF2alpha (cloprostenol) associated with less severe side effects.
  • Cabergoline Cabergoline administered orally each day for a minimum of 10 days. Prostaglandin administered commencing one day after cabergoline and given SC every two days on five occasions.
  • Combination therapy increases the efficacy of either treatment alone.
  • A blood-tinged lochia noted after 2 to 4 days.
  • May increase in volume if treatment is given early and pregnancy is terminated by resorption.
  • For later treatments, abortion commences an average of 6 days after the initiation of treatment and is complete in most cases by day 10.

Advantages

  • Control of pregnancy resulting from unwanted mating (misalliance Mesalliance ).

Disadvantages

  • Short term physical side effects (especially with PGF2alpha treatments).
  • Abortion of fetuses may be esthetically unappealing to clients, making hospitalization or boarding of bitches preferable during the treatment period.

Requirements

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Preparation

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Procedure

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Aftercare

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Prognosis

  • Excellent for termination of pregnancy.

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Cetin Y, Macun H C, Beceriklisoy H B et al (2010) Intravaginal application of misoprostol improves pregnancy termination with cabergoline and alfaprostol in dogs. Berl Munch Tierarztl Wochenschr 123 (5-6), 236-242 PubMed.
  • Pettersson C H & Tidholm A (2009) Safety and efficacy of mid-term pregnancy termination using aglepristone in dogs. JSAP 50 (3), 120-123 PubMed.
  • Onclin K & Verstegen J (1999) Comparisons of different combinations of analogues of PGF2alpha and dopamine agonists for the termination of pregnancy in dogs. Vet Rec 144 (15), 416-419 PubMed.
  • Wanke M, Loza M E, Monachesi N et al (1997) Clinical use of dexamethasone for termination of unwanted pregnancy in dogs. J Reprod Fertil Suppl 51, 233-238 PubMed.


ADDED