Pregnancy Failure in Ruminants

Question 1

Name the 3 ways pregnancy can fail

Answer 1

failure of service
failure of conception
failure of pregnancy

Question 2

Name female factors in failure of service

Answer 2

delayed uterine involution
delayed return to cyclicity
oestrus expression

Question 3

Define NEBAL

Answer 3

negative energy balance
main concern in service
less energy in the body than required for living out of work
essentially a lack of nutrition

Question 4

What cow factors control and alter oestrus expression ?

Answer 4

reproductive health
general health
BCS
metabolic stress
mobility
lameness
genetics
physical pain

Question 5

Male factors that can go wrong in natural service

Answer 5

lack of libido
ability to detect oestrus
mechanical failure (failure to mount, failure of intromission, failure of ejaculation)

Question 6

Male factors that can go wrong in AI

Answer 6

farmer’s ability to detect heat
timings being wrong
incorrect technique and handling

Question 7

Define the 12 hour, AM/PM rule

Answer 7

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…

Question 8

Name some possible aids for detecting oestrus

Answer 8

scratch pads/stickers/tail paint
raddles/chin markers
pedometers/neck monitors

Question 9

Name female factors that can go wrong in conception

Answer 9

metabolic fitness and hormonal status (NEBAL)
failure of ovulation (endocrinological problem, systemic disease, anatomical obstruction)
hostile uterine environment
uterine infections
freemartinism

Question 10

Male factors that can go wrong in natural conception

Answer 10

breeding soundness
semen quality (motility, morphology)
infections

Question 11

Male factors that can go wrong in artificial conception

Answer 11

semen quality
storage
AI technique
handling
timing

Question 12

Define EED

Answer 12

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

Question 13

Define LED

Answer 13

late embryonic death
end of differentiation
infectious or non infectious

Question 14

Define abortion

Answer 14

> 42 days
foetal development has started
infectious or non-infectious

Question 15

Define stillbirth

Answer 15

animal is born dead

Question 16

SMEDI definition

Answer 16

stillbirth
mummification
embryonic death
infertility

Question 17

other CS associated with abortion

Answer 17

systemic illness
pyrexia
milk drop
reduced appetite
visible aborted material

Question 18

Protozoal causes of infection in cows

Answer 18

Neospora (lifelong infection, late abortion, testing through sample Ab testing and PCR)

Question 19

Viral causes of abortion in cows

Answer 19

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)

Question 20

Define a PI

Answer 20

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

Question 21

Bacterial causes of abortion in cows

Answer 21

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)

Question 22

Immediate actions when see abortions in sheep

Answer 22

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)

Question 23

Bacterial causes of abortion in sheep

Answer 23

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)

Question 24

Protozoal causes of abortion in sheep

Answer 24

Toxoplasma gondii (late abortion, common to have mummification and stillbirth)

Question 25

Viral causes of abortion in sheep

Answer 25

Border Disease (sheep version of BVD, immunosuppression, barren ewes, absorption of foetus, congenital abnormalities)

Question 26

Non-infectious causes of abortion

Answer 26

systemic illness (i.e. mastitis, lameness, pneumonia)
stress (high cortisol levels)