EQUINE | Equine Disease Quarterly
with Amycolatopsis spp and one with Crossiella equi
infection, and four other cases of mucoid placentitis. can be determined with high accuracy by Doppler
flow ultrasonography.
Two cases of equine coital exanthema were confirmed
in the USA. The current trend in horse breeding is characterized
by a decline in mares that are bred and a new focus
on wellbeing of established pregnancies as well as
enhanced genetic selection with regards to health
and future performance of the foal. In addition,
great advances in the area of assisted reproductive
technologies offer numerous possibilities that were
not available in the past.
Clostridial enterocolitis was diagnosed in neonatal
foals in the USA, five of which were associated with
Clostridium perfringens infection. Additionally, four
cases of C. difficile infection were confirmed.
Of neurological diseases reported during the first
quarter of 2019, one case of rabies and nine cases
of Eastern equine encephalomyelitis were reported
by the USA, all but one in Florida. During the same
period, the RSA confirmed one case of West Nile virus
infection and 60 cases of equine encephalosis that
occurred in a total of five provinces. Mexico reported
41 outbreaks of Western equine encephalomyelitis
in the state of Nayarit. Fifty-three cases of the disease
were recorded in these outbreaks, including seven
fatalities.
Changing Trends in Equine Reproduction
Research advances in equine reproductive biology
and health over the past 50 years have contributed to
improved fertility and breeding efficiency in horses.
The development of endocrine and ultrasonography
diagnostics aids the clinician in determining potential
fertility of mares and stallions. Follicular dysfunction
and ovulation failure can be diagnosed with high
precision in mares, embryo and fetal development can
be monitored from 10 days after ovulation throughout
gestation, and fetal/placental abnormalities diagnosed
to identify high-risk pregnancies. In stallions,
biochemical and genetic sperm abnormalities have
been identified that previously remained undetected
based on traditional breeding soundness examinations.
Furthermore, testicular abnormalities and blood flow
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Monitoring Healthy Pregnancy
Biomarkers for high-risk pregnancies and efficient
treatments to prevent late pregnancy losses are being
investigated. As new potential markers for unhealthy
conditions are discovered, effective treatment options
need to be developed. A similar trend is seen with
regards to endometritis as well as the development
of new diagnostics for dormant bacteria and uterine
biofilms. While new therapeutic regimens for
endometritis often include non-antibiotic alternatives
or supplements, most treatment options for high-
risk pregnant mares include long-term use of broad-
spectrum systemic antibiotics without the possibility of
performing bacterial sensitivity tests. There is a global
awareness of consequences when antibiotics are
overused in human as well as veterinary medicine—
and equine reproduction is not an exception. An
overuse of antibiotics can lead to bacterial resistance
and contribute to one of the most urgent public health
issues today. New trends in equine reproduction
reflect these challenges to veterinary medicine, public
health and the global equine breeding industry, and
additional non-antibiotic treatment options need to be
developed.
• Equine Health Update •