2. INTRODUCTION
• Abortion is the termination of pregnancy by the removal or expulsion of a fetus of
recognizable size before it is viable.
• Pregnancies lost before 42 days (in cattle) are usually referred to as Early
embryonic deaths.
• The death of fetus before or during parturition at full term is called Still birth.
5. • The fetus that may result in abortion are not very frequently
diagnosed.
• these usually occur as an individual cow problem rather
than as a herd outbreak.
• Chromosomal abnormalities (an extra or missing
chromosomes) are known to cause abortion in farm
animals, but their importance in abortion in farm animals is
unknown.
GENETIC ABNORMALTIES
6. HEATSTRESS
Heat stress can affect reproductive performance
in a dairy herd, although it will generally cause
conception problems rather than abortions.
While there is some evidence to suggest that a
very sudden increase in environmental
temperature may result in abortions.
No matter the age of the cattle, heat stress
depresses the immune system, making them
more susceptible to other diseases.
7. TOXICAGENT
Toxic agent may also cause abortions or early
embryonic deaths.
Cattles are susceptible to the nitrates found in
plants under certain conditions.
If a cow is exposed to sufficiently high levels of
nitrates/ nitrites (~.55 % or greater nitrate in
forage), abortions may occur, especially in late
gestation.
8. Mycotoxins such as Zearalenone in
very high levels can cause
abortions in cattle, although these
levels are not normally found in
“naturally contaminated”
feedstuffs.
Likewise, the only reports of
abortions associated with Aflatoxin
appear to be situations where the
health of the cow was also
severely compromised by the toxin
9. TWINPREGNANCY
Twin pregnancy is the most common cause of abortion in
mares.
The inability of a mare to successfully carry twin fetuses
to term may be related to placental insufficiency arising
from competition between the placentae.
This may lead to the death of one fetus and eventually to
the abortion of both fetuses
11. BACTERIALCASUEOF ABORTION
1. BRUCELLOSIS:
It is a zoonotic disease characterized by abortion in
pregnant female, infertility, mastitis and retained
placentae.
Abortion due to brucellosis commonly occurs during the
last trimester of pregnancy.
Several species of the bacterium Brucella can cause
brucellosis in cattle; however, Brucella abortus is the
primary bovine pathogen.
12. The organisms enter via mucous membranes and invade the udder, lymph
nodes, and uterus, causing a placentitis, which may be acute or chronic.
Abortion or stillbirth occurs 2 weeks to 5 months after
initial infection.
Affected cotyledons may be normal to
necrotic, and red or yellow.
13.
14. LEPTOSPIROSIS
Leptospirosis is a contagious,
bacterial disease of animals and
humans.
It is a globally important zoonotic disease
caused by the pathogenic Gram negative
bacteria of the genus, Leptospira.
15. Leptospirosis can be transmitted either directly
between hosts or indirectly in the environment.
Leptospira species can be ingested in contaminated food
or water, spread in aerosolized urine or water, or
transmitted by direct contact with the skin.
The leptospira cause a diffuse placentitis with avascular.
The fetus usually dies 1–2 days before expulsion and
therefore is autolysis.
Occasionally, calves are born alive but weak.
16. Abortion usually occurs during the last trimester of pregnancy but
can occur from the 4th month onwards.
Infertility and milk drop occurs only in pregnant or lactating cows
because Leptospira organisms prefer pregnant uterus and lactating
mammary gland to proliferate.
17. VIRALCAUSESOF ABORTION
BOVINE VIRAL DIARRHEA:
Bovine viral diarrhea is a disease caused by
bovine viral diarrhea virus (BVDV).
It is an important cause of diarrhea,
reproductive problems and reduced milk
yield in affected herds.
18. BVD virus is immunosuppressive and
is found in many fetuses with
infections caused by other agents.
20. The virus is carried to the placenta in WBCs; over the next 2
weeks to 4 months, it causes a placentitis, then infects the
fetus and kills it in 24 hours.
Abortion can occur any time but
usually is from 4 months to term.
21.
22. REFERENCE
• Ahmed tibary, (2021), abortion in cattle, Washington.
• John currin, (1999), common causes of abortion, Virginia. (USA)
