Bovine Reproductive Failures Flashcards
Name the 4 causes of failure of fertilisation
- Poor ova quality
- Poor sperm quality
- Timing of insemination
- Insemination technique
What insemination factors can cause a failure of fertilisation?
- Insemination technique
2. Timing of insemination
Ovulation delay/failure can cause what?
Fertilisation failure
What 3 factors affect sperm quality??
- Heat stress
- Semen handling
- Semen preservation technique
Poor endocrine environment adversely affects _____ development and _____ quality.
Poor endocrine environment environment adversely affects follicle development and oocyte quality.
Impaired luteal function affects what 3 aspects of fertility?
- Early embryonic development
- Maternal recognition of pregnancy
- Implantation
Impaired function of the endometrium affects what 3 aspects of fertility?
- Early embryonic development
- Maternal recognition of pregnancy
- Implantation
Name 3 causes of freemartinism.
- Heterosexual twin
- Fusion of chorioallantois
- Chimeras
What is the best diagnostic method to determine subclinical endometritis in the cow?
Uterine cytology
What is the vaginal discharge score for clinical endometritis?
4-5
What is the vaginal discharge score for subclinical endometritis?
2 - 3
Puerperal metritis is an a____ s_____ b_____ disease
Puerperal metritis is an acute systemic bacterial disease
What is metritis treated with?
Parenteral antimicrobial (oxytet, penicillin)
What is endometritis treated with?
PGF (luteolysis) Uterine antimicrobials (cephapirin)
What method of diagnosis is best used for bacterial abortions?
Bacterial isolation
Is Brucellosis zoonotic?
Yes
Is Brucellosis found in Australia?
No
How is Brucella abortus transmitted?
Ingestion/inhalation of contaminated material
Name 3 signs of Brucellosis
- Metritis
- RFM
- Abortion
Brucellosis causes abortion > 5 month. True/False?
True
How is Campylobacter fetus transmitted?
Venereal transmission
Bulls are the main source of Campylobacter fetus. True/False?
True
Repeat breeders is a sign of what?
Campylobacter fetus spp
An irregular and delayed return to oestrus and longer calving season is a sign of…….
Campylobacter fetus spp infection
Where does Leptospirosis persist in the animal?
Renal and genital tracts
What is the hallmark sign of a Leptospirosis infection?
abortion storms
How is Leptospirosis transmitted (2 ways)?
Urine
Venereal
Spoiled silage can lead the transmission of what bacteria?
Listeria monocytogenes
‘Droopy cow’ describes when half an animal’s face appears to droop. What type of bacteria causes this?
Listeria monocytogenes
An autolysed fetus is a sign of what bacterial infection?
Listeria/listeriosis
What time of year is the incidence of mycotic abortions the highest?
Winter
What is the main causative agent of mycotic abortions?
Aspergillus fumigatus
What causes necrotizing placentitis with a leathery appearance?
Mycotic abortions
Fetal skin lesions are associated with…..
Mycotic abortions
Is Bovine Herpes Virus (BHV 1-5) a latent infection?
Yes- latent
What are the 2 routes of transmission for BHV?
- Venereal
2. Direct contact (aborted fetus)
Sporadic abortions can occur with BHV due to previous exposure or vaccination. True/False?
True
Do abortion storms due to BHV occur in the non-vaccinated herd population or vaccinated/previously exposed herd population?
Non-vaccinated/non exposed herd population
Where in the animal does BHV reside?
Placenta
What is another name for Bovine Viral Diarrhoea Virus (BVDV)?
Pestivirus
BVDV persistent infected calves do not usually show any signs of disease, however they are still infected and do what?
Shed large amounts of virus
A transplacental infection usually results in the calf being….
PI animal (persistently infected animal)
The acute form of BVDV causes what?
Immune suppression
BVDV infection results in what % reduction in pregnancy rates?
50% reduction
How does a BVDV infection affect follicle size?
Smaller preovulatory and ovulatory dominant follicles
How does BVDV affect E2 production?
Lower E2 production
Delayed E2 peak
How does BVDV affect LH peaks?
Reduced LH peaks
Impaired luteinization
How is Akabane virus transmitted?
Biting midges
What happens if an animal is infected with Akabane virus at a young age?
Long lasting immunity develops
What are the consequences if infection of Akabane virus occurs during pregnancy?
Fetal abnormalities
If infected with Akabane virus >180 days, what is the incidence of abnormal calves?
Low 5-10%
If infected with Akabane virus 80-150 days, what is the incidence of abnormal calves?
40%
Name 2 protozoal causes of infertility and abortion in the cow.
- Trichomoniasis (Trichomonas fetus)
2. Neosporosis (Neospora caninum)
What are the definitive hosts of Neospora caninum?
Dogs/canids
Neospora caninum an intracellular host. True/false
True
How is Trichomonas foetus transmitted?
Coitus
Which protozoa causes mummified/autolysed fetus?
Neospora caninum
Which protozoa is associated with repeat breeders?
Trichomonas foetus