Bovine Infectious Infertility and Abortions Flashcards
What is early embryonic death?
Fetal death less than 8 weeks.
What is early embryonic death?
Fetal death less than 8 weeks.
What is abortion?
Fetal death between 42/56 days and 260 days.
What is stillbirth?
Fetal death after 260 days.
What is intervention level?
<5% of a herd
What si the number 1 diagnosis of abortion?
“Unknown”
What is Listeria monocytogenes?
Gram positive coccobacillus.
Where do you find Listeria monocytogenes?
Everywhere, but it’s concentrated in rotting hay and improperly stored silage.
What sites does Listeria have a predilection for?
Fetoplacental tissue
What are the two main clinical signs you see with listeriosis?
Abortion in the last trimester
SICK INFECTED COWS
NOTE: This is one of the only bacteria where you will also see a sick cow!!!
How do you diagnose listeriosis?
Isolation of organism from fetal tissues and placenta.
What 2 lesions might you see with listeriosis?
Autolysed fetus
Pinpoint, yellow necrotic foci on placenta
How do you treat listeriosis?
The cow usually recovers on her own.
What are 3 ways you can prevent listeriosis?
Proper silage storage
Clean up old hay
Don’t feed rotten material to pregnant animals
What is abortion?
Fetal death between 42/56 days and 260 days.
What is stillbirth?
Fetal death after 260 days.
What is intervention level?
>#5% of a herd.
What si the number 1 diagnosis of abortion?
“Unknown”
What is Listeria monocytogenes?
Gram positive coccobacillus.
Where do you find Listeria monocytogenes?
Everywhere, but it’s concentrated in rotting hay and improperly stored silage.
What sites does Listeria have a predilection for?
Fetoplacental tissue
What are the two main clinical signs you see with listeriosis?
Abortion in the last trimester
SICK INFECTED COWS
NOTE: This is one of the only bacteria where you will also see a sick cow!!!
How do you diagnose listeriosis?
Isolation of organism from fetal tissues and placenta.
What 2 lesions might you see with listeriosis?
Autolysed fetus
Pinpoint, yellow necrotic foci on placenta
How do you treat listeriosis?
The cow usually recovers on her own.
What are 3 ways you can prevent listeriosis?
Proper silage storage
Clean up old hay
Don’t feed rotten material to pregnant animals
What is leptospirosis?
Aerobic spirochete
What serovars of lepto are zoonotic?
All of them
What are the two types of lepto that we need to worry about?
Host adapted
Non host adapted
What clinical signs do the host adapted types of lepto cause?
Insidious repro loss or infertility.
NOTE: Host adapted lepto tend to have “hardjo” in the name
What clinical signs do the non host adapted types of lepto cause?
Abortion storms
How long is the incubation period of lepto?
4-10 days
Where does lepto localize and persist?
The renal tubules.
What general clinical signs do you see with lepto infections?
Often none.
What 5 ways is lepto transmitted?
URINE Placental fluids Milk Transplacental Semen
What are the main 3 ways lepto is diagnosed?
Clinical history
Dark field microscopy
Fluorescent antibody (using fetal kidney or maternal urine)
What 2 things can you do to prevent lepto?
Limit exposure to wildlife
Vaccinate
What is Brucella abortus?
Intracellular gram negative coccobacillus
What is the zoonotic form of brucella?
Undulant fever
What is the primary means of transmission of brucella?
Mucus membranes
Who do you usually blame in cases of brucella?
The “bull” (can also be transmitted by intrauterine deposition of frozen semen.
NOTE: Sire bulls should always be tested for brucella
What clinical sign for you see with brucella?
Abortion, frequently after 5 months gestation.
What is the deffinitive diagnosis of brucella?
Isolation of the organism.
What is a finding that is suggestive of brucellosis?
Placentitis (moroccan leather)
What is REALLY important to remember about brucella?
It is REPORTABLE in the USA
What is the treatment for brucellosis?
No treatment for positive cases. Can only prevent via vaccination of heifers.
What is the current brucella vaccine strain?
RB51
Since brucella is reportable, it is monitored by the government, how do they go about that?
Orange tags in the right ear (right ear is always for the gov’t) and a tattoo of “Rsheild#”, with the number being the last digit of the year.
What are 2 uncommon and sporadic bacterial causes of abortion?
Mycoplasma
Ureaplasma
What are 3 minor players when it comes to infectious causes of abortion?
Haemophilus somnus
Chlamydia
Salmonella
What is Campylobacter foetus veneralis?
Gram negative microaerophilic rod
NOTE: It is an obligate parasite of the bovine.
What bacteria is an obligate parasite of bovines?
Campylobacter foetus veneralis
What is another name for Campylobacter foetus veneralis?
Vibrio
What 2 strains of campylobacter can be found in the GIT?
C. fetus fetus
C. fetus jejuni
Why are we not worried aboout the other two strains of vibrio?
Because they aren’t transmitted venereally.
How is vibrio transmitted?
Coitus
What type of fetal deal does vibrio cause?
Early embryonic death
What are clinical signs of vibrio?
Cows have a delayed return to estrus.
Bulls have no signs.
What percentage of cows abort their fetus when infected with vibrio?
Less that 10%
How is campylobacter diagnosed?
Preputial scrapings on Clark’s media.
NOTE: Can also use vaginal mucus or fetal abomasal contents or the placenta.
What are 3 ways to conrtol the spread of vibrio?
AI
Use Camp negative bulls
Vaccines (vaccinate before breeding season with 2 injections 2-4 weeks apart, and an annual booster)
What is Tritichomonas foetus?
A flagellated protozoa
Where does tritrichomonas live?
Preputial crypts.
Why do older bulls have higher numbers of tritrichomonas?
They have deeper preputial crypts.
How is tritrichomonas transmitted?
Via coitus.
What does tritrichomonas cause?
Fetal death, usually early embryonic death.
How do you diagnose tritrichomonas?
Herd history in females. Usually subclinical in males.
What 21-day histogram would suggest that an animal is infected with tritrichomonas?
A reverse stair-step. (eg. 10, 2, 4, 6, 8)
What 4 samples can be used to diagnose tritrichomonas?
Fetal fluids (amnion, abomasum)
Uterine contents
Cervicovaginal mucus
Preputial wash
If submitting a preputial wash to look for tritrichomonas, what do the samples go in?
Diamond’s medium or InPouch
What is the protocol for testing for tritrichomonas?
After 2 weeks sexual rest, samples to be taken once a week for 3 consecutive weeks. All samples undergo PCR to type.
What is different about the tritrichomonas vaccine?
It doesn’t prevent the dz, merely shortens it’s recovery interval. So you vaccinate infected females.
How do you prevent tritrichomonas?
Use only culture negative or bulsl less than 4 years of age.
What is neospora caninum?
A protozoa
How is neospora transmitted?
Dogs are the definitive host, the protozoa is primarily transmitted vertically.
What clinical disease does neospora cause in the dam?
None
What clinical disease does neospora cause in the calf?
Either Normal, Weak or Aborted.
What lesion do we see with neospora?
Autolysed fetus
What 2 ways can we diagnose neospora?
IHC on fetal tissues and placenta
Serologic testing
What 2 ways can we prevent/control neospora?
Disrupt the predator-prey lifecycle
Store and serve feed and water in a way that prevents fecal contamination
What is the agent that causes infectious bovine rhinotreacheitis?
Bovine herpesvirus 1
What is the most frequently diagnosed cause of viral abortion in North America?
Infectious bovine rhinotracheitis
What kind of transmission to we need to be aware of with infectious bovine rhinotracheitis?
Aireborne transmission
What are the two forms of IBR that we see?
Veneral
Systemic
Where is the IBR virus shed?
Aborted fetus
Respiratory
With the systemic form of IBR, when do we see abortions?
Between 4 and 8 months gestation
Besides abortions, what clinical sign might we see with systemic IBR?
Sometimes respiratory signs
What do we see clinically with the veneral form of IBR?
Pustules or nodules
How is IBR diagnosed?
Autolysed fetus and foci of necrosis in liver and other organs are suggestive.
How is veneral IBR treated?
Resolves spontaneously in 1-2 weeks
What are 3 control/prevention measures for IBR?
Biosecurity
Vaccination
AI with negative semen
What is a big thing to remember with regard to vaccinating for IBR?
Follow the manufacturer’s instructions
What virus causes the most reproductive problems?
Bovine viral diarrhea virus (BVDV)
What are the 2 different categories to divide BVDV into?
Genotype
Biotype
What are the 2 genotypes of BVDV?
BVDV1
BVDV2
What are the 2 different biotypes of BVDV?
Cytopathic
Noncytopathic
What biotype of BVDV results in the persisntently infect calves?
Noncytopathic
What is the primary source of BVDV spread?
Persistently infected calves, because they are constantly shedding.
What are the 3 outcomes of BVDV infection?
If infected BEFORE 120 days gestation, you get a persistently infected calf.
If infected AFTER 120 days gestation, calf will either fight off infection or lose the fight and abort.
Why is 120 days gestation so important with regards to BVDV?
That’s when the immune system begins to form, so calves infected with BVDV before this will have the virus considered as “self” and won’t fight it.
What are the 2 sources for horizontal transmission of BVDV?
Persistently infected calves**
Acutely infected animals
What do we have to be careful of with BVDV?
Virus can be transmitted by fomites so be really freaking careful about what you do, and clean all your shit between farms!
What is important to remember about the clinical signs of BVDV?
Most show no clinical signs!!! SCREEN ALL YOUR ANIMALS!
What are 3 clinical signs of BVDV?
Ill thrift
Intermittent diarrhea
Chronic respiratory dz
What is considered diagnostic confirmation of BVDV?
Virus neutralization negative with tests 14 days apart.
Virus isolation positive for 14 days or longer.
What are the 2 general economic impacts of BVDV?
Reproductive losses
Production losses
Which type of bovine production is more affected by BVDV?
Beef and dairy are both equally affected.
What are the 2 best diagnostic tests for BVDV according to Dr. French?
Immunohistochemistry
PCR
What is a benefit of running PCR for BVDV?
Can run pooled samples.
What are 2 benefits of using IHC to test for BVDV?
Can use an ear notch sample.
Maternal antibodies don’t interfere.
What are 2 ways to control BVDV?
Biosecurity (closed herd)
Vaccines FOLLOW MANUFACTURER’S LABELS
What should BVDV control stragtegies aim for?
Detection and elimination of PIs
What species does bluetongue virus infect?
Cattle and sheep
How frequently does bluetongue virus cause abortions?
Only a minor cause, more commonly causes teratogenesis.
What is important to remember about the vaccines for bluetongue virus?
They’re only MLV, so it may propagate the dz if the vector is present!
What type of virus is the bluetonge virus?
An orbivirus.
What fungus can cause abortions?
Aspergillus fumigatus
When do we see transmission of aspergillus most?
In the winter and spring during increased confinement of cattle.
What type of spread do we see with aspergillus?
Hematogenous.
How does aspergillus cause abortions?
Hematogenous spread causes placentitis which results in abortion.
What 2 lesions do we see with aspergillus abortions?
Necrosis of the cotyledons and thickening of the intercotyledonary space on the placenta
Mycotic plaques in ~25% of the cases on the fetus (looks like ringworm lesions)
How is aspergillus diagnosed?
Fungal hyphae on microscope of histopath.
