Pregnancy failure in ruminants I Flashcards
What are the female factors that affect failure of service?
- Delayed uterine involution- due to uterus infection (not ready to recieve pregnancy)
- Delayed return to cyclicity
- Oestrus expression
What are the male factors that affect failure of service?
- libido/ oestrus detection and mechanical failure in natural service
- Oestrus detection/ AI technique in artifical insemination
What can cause delayed uterine involution?
- Dystocia/ Assisted calving
- Treatment and resolution of infection/ inflammation
- Retained foetal membranes
What can cause a delayed return to cyclicity?
- Negative energy balance
- PP uterine inflammatory disease
- cystic ovarian disease and anoestrus
What are some ‘cow factors’ that effect oestrus expression?
- returning to cyclicity
- reproductive health
- General health and BCS
- metabolic stress
- Mobility/ lameness (basic hoof pathology)
What are some ‘management factors’ that effect oestrus expression?
- loafing area access
- underfoot conditions
- sexually active group
What three things can make natural service unsuccessful?
- Failure to mount
- Failure of intromission
- Failure of ejaculation
What may you observe when a cow is in oestrus?
- Increased activity
- standing to be mounted
- occurs at least 30 minutes twice per day
- they will be as far from milking/feeding as possible
What are two ways that oestrus can be detected for artificial insemination?
- thick waxy paint/ tail paint
- raddles/ chin marker
What is a pedometer used for?
- Oestrus detection
- detects increased activity
What are the male factors that affect conception?
- semen quality
- infectious agents
- timing of AI
- semen handling and AI technique
How can acyclicity effect a failure to ovulate?
- reduced magnitude of an LH surge
What is an example of an anatomical problem causing failure to ovulate?
Obstruction of the uterine tube (salpingitis)
What is salpingitis?
Obstruction of the uterine horn
When does vaginal recession occur?
- Due to faecal contamination
- is more likely in thin cows
What is early embryonic death and when does it occur?
- Losing of the CL (occurs prior to CL maintenenace)
- Less than 15-17 days
What is late embryonic death and when does it occur?
- Corpus luteum regresses (occurs during differentiation)
- occusr less than 42 days after ovulation
What does SMEDI stand for?
- Stillbirth
- Mummification
- Embryonic Death
- Infertility
What are the clinical signs of infectious abortion?
- Pyrexia
- Milk Drop
- Reduced appetite
- Visible aborted material
- often accompanied by a systemic disease
How can you diagnose infectious abortion?
- Sample collection and submission to an approved lab
What is neospora caninum?
Protozoan parasite
What is the lifecycle/ transmission of neospora caninum?
in the direct host- dogs
Dogs eat infected placenta/ aborted tissue
they then produce sporozoites in their faeces
infected faeces is then grazed on by cattle
How does neospora present?
- Late abortion between 5-7 months
How do you test for neospora caninum?
- Take a sample on the last day of abortion as antibodies peak in the last 2 weeks of gestation
- Can take a PCR on foetal tissue
- identify infected cattle and either do not breed the replacements or cull them
How is BVD transmissed?
- either the faecal/oral route
- transplacental
What are the clinical signs of BVD?
- Immunosuppression
- Milk Drop
- Abortion
What is the significance of getting BVD at 1-4 months of pregnancy?
The calf gains immunotolerance to it
What is the diagnosis for BVD virus?
- Dam serology for antibody
- Viral antigen testing
- PCR on the foetal spleen
What are the clinical signs of leptospira hardjo?
- Milk drop
- Pyrexia
- Abortion/ Infertility
- Infected animals become chronic renal carriers
What are the clinical signs of Bovine Herpes Virus?
- Severe Upper Respiratory Tract Disease
- Vulvovaginitis/ balanoposthitis
- Exposed cattle become latently infected
- They start shedding during periods of stress
- causes abortion storms
What bacteria is found in spoiled silage?
Listeria monocytogenes
What is listeria monocytogenes associated with?
Associated with ‘silage eye’
How can you diagnose listeria monocytogenes?
Using a culture from foetal stomach contents/ placenta
What are the clinical signs of schmallenberg virus?
- Hydranencephaly (brain sacs are filled with fluid)
- Arthyrogryposis (joint stiffness)
What are the clinical signs of Q fever?
- Often subclinical
- Abortion/ Inappetence
- Necrotising placentitis
- Long lasting immunity
What is the diagnosis of Q fever?
- Impression smear of intercotyledonary placenta for acid fast bacteria
How would you manage an ewe that has aborted?
- Isolate the aborting ewe and record the ID
- clinical examination of evidence of systemic disease
- Do not foster any lambs
What is the presentation of chlamydophilia abortus?
- inter-cotyledonary placentitis
- Pregnant ewes abort
- they only abort once then they are immune
From how many days can you make a pregnancy diagnosis in dairy cattle?
From 28 days
What may cause failure of intromission in natural service?
- Nerve damage- no ejaculation
- Penile deviation/ Penile fracture
- May be behavioural
How long should ‘standing to be mounted’ last?
30 minutes twice a day
What may you use to help detect oestrus in ewes?
- Wax crayon attached to rams in a harness
What is the normal cause of acyclicity?
- Reduced magnitude of LH surge
- Systemic Disease
How is Semen usually stored on the farm?
what element is used
Nitrogen
Name three anatomical factors that can effect the ability to ovulate in females?
- If the cow is a freemartin
- Salpingitis
- Vaginal recession (may be due to faecal contamination)
After how many days is pregnancy loss considered to be rare?
70+ days
What does poor sperm quality usually reflect?
historic problems
What are the direct and intermediate hosts of neospora caninum?
- Direct- Dogs
- Intermediate- Cows
What is the definitive host of toxoplasma gondii?
Cats
How does toxoplasma spread?
Spreads via oocysts in the faeces, they survive for a long time in the environment (zoonotic)
How would you diagnose toxoplasma
grossly
Pale calcified areas on cotyledons
Serology titre
Histopathology on the placenta
What are the clinical signs of border disease virus?
- Immunosupression
- Barren ewes
- Abortion
- Congenital abnormalities
- Hairy shakers
How would you diagnose BVD?
- Dam serology for the antibody
- Serology for the vital antigen
- PCR on the foetal spleen
How is Q fever spread?
Via ticks
What salmonelliosis types are found in cattle?
- S.dublin
- S.typhimurium
What salmonelliosis types are found in sheep?
- S. abortus ovis (rare UK), S. montivideo (birds), S. typhimurium (sewage), S. dublin (cattle)
What three things may cause artificial insemination to fail?
- Failure to mount
- Failure of intromission
- Failure of ejaculation (nerve damage…)
What is the effect of oxytetracycline on the male?
May decrease sperm quality
Why is quality on insemination variable?
- On-farm storage
- Thawing and handling
- Delay to insemination
- AI timing and technique
What foetal abnormalities does BVD cause?
- Congenital cataracts
- Cerebral hypoplasia/ aplasia
