Pregnancy Failure in Ruminants Flashcards
(26 cards)
Name the 3 ways pregnancy can fail
failure of service
failure of conception
failure of pregnancy
Name female factors in failure of service
delayed uterine involution
delayed return to cyclicity
oestrus expression
Define NEBAL
negative energy balance
main concern in service
less energy in the body than required for living out of work
essentially a lack of nutrition
What cow factors control and alter oestrus expression ?
reproductive health
general health
BCS
metabolic stress
mobility
lameness
genetics
physical pain
Male factors that can go wrong in natural service
lack of libido
ability to detect oestrus
mechanical failure (failure to mount, failure of intromission, failure of ejaculation)
Male factors that can go wrong in AI
farmer’s ability to detect heat
timings being wrong
incorrect technique and handling
Define the 12 hour, AM/PM rule
AI should be given to the cow 12 hours after you observe the standing oestrus behaviour. If the behaviour is in the morning, always give the AI in the afternoon, etc…
Name some possible aids for detecting oestrus
scratch pads/stickers/tail paint
raddles/chin markers
pedometers/neck monitors
Name female factors that can go wrong in conception
metabolic fitness and hormonal status (NEBAL)
failure of ovulation (endocrinological problem, systemic disease, anatomical obstruction)
hostile uterine environment
uterine infections
freemartinism
Male factors that can go wrong in natural conception
breeding soundness
semen quality (motility, morphology)
infections
Male factors that can go wrong in artificial conception
semen quality
storage
AI technique
handling
timing
Define EED
early embryonic death
<15-17 days
prior to CL maintenance
infectious or non-infectious
often difficult to know it has happened
often caused by failure of maternal recognition of pregnancy
Define LED
late embryonic death
end of differentiation
infectious or non infectious
Define abortion
> 42 days
foetal development has started
infectious or non-infectious
Define stillbirth
animal is born dead
SMEDI definition
stillbirth
mummification
embryonic death
infertility
other CS associated with abortion
systemic illness
pyrexia
milk drop
reduced appetite
visible aborted material
Protozoal causes of infection in cows
Neospora (lifelong infection, late abortion, testing through sample Ab testing and PCR)
Viral causes of abortion in cows
BVD (causes immunosuppression, milk drop, infertility and abortion)
BHV-1 (causes infectious bovine rhinotracheitis, carrier for life, causes upper resp tract dissease with abortion storms)
Schmallenberg (associated with a vector, CS include hydranencephaly and arthrogryposis)
Bluetongue (midge vectors)
Define a PI
persistently infected animal
when the foetus does not yet have a developed immune system and so the foetus recognises the virus as a part of its normal body functions. They can abort or be born with defects, but most are born completely fine. These animals act as life-long shedders and are the most common source of infection
Bacterial causes of abortion in cows
Leptospirosis (uncommon in the UK, spread in urine, see “flabby bag”, milk drop, abortion and infertility)
Salmonella (wildlife reservoir, if see CS then very severe disease)
Listeria monocytogenes (soil bacteria, grows in poorly made silage, associated with grazing fields too close to the ground, associated with “silage eye”, uveitis and meningoencephalitis)
B. licheniformis (grows in mouldy cereals, causes mastitis)
Q fever (often subclinical, spread in wildlife and ticks, necrotizing placentitis)
Brucellosis (notifiable !! most commonly Brucella abortus)
Immediate actions when see abortions in sheep
management of ewe (isolate, record ID, clinical exam)
management of aborted material (submit foetus and placenta for PM)
management of environment (disposal of bedding, cleaning, disinfection, biosecutiry)
Bacterial causes of abortion in sheep
Chlamydia abortus (late abortion, if ewe is not pregnant she will abort her next pregnancy, only abort once then immune, likely to cull positive animals)
Protozoal causes of abortion in sheep
Toxoplasma gondii (late abortion, common to have mummification and stillbirth)
