Page 989 - Small Animal Internal Medicine, 6th Edition

CHAPTER 55 Clinical Conditions of the Bitch and Queen 961

for which sound studies provide support. Breeder clients SEMEN PERITONITIS
often request therapies they have heard about through The differential diagnoses for a sexually intact bitch with
VetBooks.ir the grapevine or on the Internet, usually anecdotal and acute onset of signs of abdominal pain include pyometra,
uterine rupture, and uterine torsion. Acute peritonitis sec-
often without clinical data supporting their use. The con-
sequences of mistreating pregnant or nursing bitches or
should also be considered in the estrual bitch with acute
neonates should limit the clinician to prescribing therapies ondary to deposition of semen into the abdominal cavity
with sound scientific rationale in most cases. During the signs of abdominal pain and a history of possible exposure
first month of pregnancy, organogenesis takes place, and to an intact male dog, or with a recent history of artificial
the impact of potentially teratogenic drugs is most critical. insemination. Semen is forced into the uterus during the
At therapeutic levels, most drugs in the maternal blood- copulatory lock because of the large amount of prostatic fluid
stream are capable of crossing the placenta to reach fetal in the final fraction of the canine ejaculate. Normally the
circulation. Even before implantation, drugs in mater- semen should not enter the peritoneal cavity of bitches after
nal circulation reach embryos. Any drug that reaches the mating, but in the case of mates mismatched in size or a
fetal circulation must be metabolized and excreted by diseased uterus, semen could be forced into the peritoneal
the immature fetal kidney and/or through subfunctional cavity through a tear in the uterus or vagina or through the
hepatic metabolism. Clinicians should evaluate the package fallopian tubes. Intraperitoneal deposition of semen results
insert on any drug before prescribing its use in pregnant in peritonitis because prostatic fluid contains a large amount
bitches. Cautions for use in pregnant or lactating individu- of foreign antigens. Severe suppurative peritonitis and the
als will be outlined as “safe, untested/unknown, or prob- systemic inflammatory response syndrome are likely sequelae
lematic.” Extrapolation across species may not be reliable (Fig. 55.7, A, 55.7, B). Stabilization followed by exploratory
(i.e., tested in laboratory mice). Dose reduction of many
drugs is advised, but guidelines are lacking (Wiebe and
Howard, 2009).

VACCINATION DURING PREGNANCY
Shelter personnel may be faced with the dilemma of vac-
cinating a pregnant bitch or queen upon admission to a 10
facility. Bitch and queen owners commonly request booster
vaccinations before breeding. Historically, vaccination in
pregnancy has been advised against in small animal medi-
cine, because of the paucity of data concerning vaccine
safety and efficacy during gestation, and because it is
accepted that no substance should be administered unnec-
essarily during pregnancy. However, when the immu-
nity of the dog or cat is unknown, the risk of maternal,
fetal, and neonatal infection must be weighed against that A
of vaccination. The U.S. Centers for Disease Control and
Prevention states that risk to a developing fetus from vac-
cination of the mother during pregnancy is primarily the- 10
oretical, that no evidence exists of risk from vaccinating
pregnant women with inactivated viral or bacterial vaccine
or toxoids, and that the benefits of vaccinating pregnant
women usually outweigh potential risks when the likeli-
hood of disease exposure is high. Further research in vac-
cination of pregnant dogs and cats is needed; extrapolating
from the human field is advised at this time. The shelter
environment provides an example of likely disease expo-
sure in the face of unknown vaccination history, warrant-
ing vaccination of pregnant dogs upon admission with
canine distemper virus, parvovirus, and bordetella bron-
chiseptica (intranasal/oral), and cats with feline viral rhi- B
notracheitis, calicivirus, and panleukopenia. Inactivated,
subunit, recombinant, polysaccharide conjugate vaccines FIG 55.7
should be selected for use in the pregnant dog/cat if avail- Semen peritonitis. (A) Cytology of peritoneal fluid showing
able. Client-owned bitches should not be boosted during toxic neutrophils, red blood cells, and a spermatozoon head
pregnancy if they have been vaccinated within the previous are present. (B) Phagocytosis of a spermatozoon head
3 years, queens (recombinant) if within 1 year. (arrow).