Page 994 - Small Animal Internal Medicine, 6th Edition

966 PART VIII Reproductive System Disorders

gastrointestinal, and respiratory disorders. Toxoplasmosis antibodies via colostrum. Bitches can be screened before
can be spread venereally. The diagnosis is based on serology breeding for CHV-1 titers; negative serology should prompt
VetBooks.ir and PCR. Cryptosporidia canis and C. felis develop in the strict hygiene and isolation during the last 3 weeks of preg-
nancy and the first month postpartum. Vaccine development
microvillus border of epithelial cells in the digestive, respira-
tory, and genitourinary tracts and can cause abortion. The
rus, as evidenced by other herpesviral vaccines developed
diagnosis is made with the direct immunofluorescent anti- is hampered by the poor immunogenicity of the herpesvi-
body (IFA) test or PCR. for different species, such as feline and bovine rhinotrache-
itis. A commercial CHV vaccine is currently available in
Europe; it has not been subjected to nonproprietary critical
CANINE VIRAL-ASSOCIATED evaluation.
PREGNANCY LOSS
Herpes Virus Minute Virus
Adequate exposure of a non-immune bitch to canine herpes- Canine Minute Virus (canine parvovirus type 1) causes
virus (CHV-1) during the last 3 weeks of gestation can result resorption and abortion after transplacental transmission.
in infection of the dam and subsequently her neonates. Any fetuses surviving to term can have anasarca and myo-
Venereal transmission is believed to be rare and community carditis, with poor neonatal survival. The diagnosis is based
(respiratory) transmission more common. Signs in the bitch on virus isolation, immunofluorescence, or PCR.
are usually limited to a mild, clear upper respiratory dis-
charge and transient sneezing; however, reports of a more
severe respiratory form of CHV-1 exist in adult dogs, often FELINE VIRAL-ASSOCIATED
with other viral coinfections (Piewbang et al., 2017). Infec- PREGNANCY LOSS
tion in the naïve pregnant bitch commonly results in late Leukemia Virus (FeLV), Panleukopenia
term abortion or neonatal death within the first few weeks Virus (FPV), Herpes Virus (FHV), Infectious
of life. The recently infected bitch has inadequate time to Peritonitis (FIP), and Feline
form protective maternal antibodies and allow passive Immunodeficiency Virus (FIV)
immunity (transplacental or transmammary) to be acquired Viral-associated pregnancy loss is in the queen is more
by the neonates. Incompletely developed immune systems common than bacterial; reproductive failure can be associ-
and inadequate thermoregulation during the first weeks of ated with feline leukemia virus (FeLV), feline panleukopenia
life make neonates vulnerable to systemic viral infection. virus (FPV), feline herpes virus (FHV), feline infectious
Adequate ingestion of colostrum must occur promptly post- peritonitis (FIP), and feline immunodeficiency virus (FIV).
partum for puppies to acquire passive immunity. The trans- Viral transmission can occur transplacentally, via oronasal
mission of protective immunity (placental or colostral contact, and in some cases can be transmammary. Infection
antibodies) between a bitch and her puppies depends upon can result in resorption, mummification, or abortion of
the prior existence of adequate serum maternal antibodies. fetuses, as well as neonatal death. Abortion PCR and culture
CHV-1 can evade the immune system and become latent in panels are commercially available. The queen and tom cat
the nervous system; immunosuppression during pregnancy should be FIV antibody- and FeLV antigen-screened and
can promote viral reactivation, but if this occurs it will likely appropriately vaccinated. The most effective management
boost the immune response and increase the level of colos- system to prevent infectious causes of pregnancy loss in the
tral antibodies available to neonates. queen include rigorous health maintenance of both the
Transmission of herpesvirus from an infected, viremic queen and tom, routine annual screening for underlying
dam to neonates occurs subsequent to contact with infec- health problems, retrovirus status, and excellent nutrition.
tious vaginal fluids or oronasal secretions. Signs in the Queens should be maintained in a closed colony environ-
neonate are progressive and severe, and include anorexia ment and new additions to the colony quarantined.
(poor weight gain), dyspnea, abdominal pain, incoordina-
tion, diarrhea, serous to hemorrhagic nasal discharge, and Vector Borne Disease
petechiation of the mucous membranes. The mortality rate Babesiosis and leishmaniasis have both been implicated in
in untreated litters infected in utero or during birth is com- canine abortion.
monly 100%, with deaths occurring during the first few days
to 3 weeks of life. Infection in neonates born to a non-
immune bitch may also result from contact with CHV-1 METABOLIC DISORDERS
from another dog shedding the organism in the vicinity.
Older naive (>3-4 weeks of age) puppies exposed to herpes- HYPEREMESIS GRAVIDARUM
virus may have an inapparent infection; some authors have Bitches can experience a transient loss of appetite and some-
reported concerns with later central nervous signs includ- times have periodic vomiting during the second and third
ing blindness and deafness. Subsequent litters of the bitch weeks of gestation. This usually resolves spontaneously, but
infected during a previous pregnancy are usually resistant sometimes marked anorexia hinders adequate nutrition
to infection, having acquired adequate circulating maternal during gestation. Antiemetic therapy can be helpful with