Term
| What are the 2 'categories' of repro problems, and indicators for each? |
|
Definition
Management
-chronic losses for 3+ months
Disease
-rapid change in production
-reductions in multiple areas (stillbirths, litter size, conception etc) |
|
|
Term
What are the repro targets for swine?
Farrowing Rate
Total born/litter
Born alive/litter
Stillborn/litter
Mummified pigs
Gestatoin length |
|
Definition
Farrowing Rate >85%
Total born/litter ~12
Born alive/litter ~11
Stillborn/litter <0.5
Mummified pigs <1.5%
Gestation length 110d |
|
|
Term
| What are the agent factors causing parvovirus? |
|
Definition
-Porcine Parvovirus
-stable, endemic infection
-causes embryonic & fetal death |
|
|
Term
| What are the clinical signs of parvovirus? |
|
Definition
-increases in sows returning to etrus after breeding
-decrease in number of piglets born alive
-increase in mummified piglets
-many gilt litters affected |
|
|
Term
| If you have a litter of mummified fetuses of all varying sizes, what disease is likely the cause? |
|
Definition
|
|
Term
| What can you do to control Parvovivrus |
|
Definition
-vaccination, but almost impossible to eliminate
Gilts - 5 & 2 wks pre breeding
Sows - 2 wks pre breeding
Boars - anually |
|
|
Term
| What host factors contribute to parvovirus |
|
Definition
immunity (vaccination)
gilts |
|
|
Term
| What environmental factors contribute to parvovirus |
|
Definition
contaminated facilities
carrier pigs present |
|
|
Term
| What disease is caused by erysipelothrix rhusiopathiae |
|
Definition
|
|
Term
| Describe the characteristics of erysipelothrix rhusiopathiae |
|
Definition
-resistant to drying but susceptible to disinfectants
-infected swine shed profusely
-produces toxin that damages blood vessels
POTENTIALLY ZOONOTIC |
|
|
Term
| What are the the clinical signs of erysipelas |
|
Definition
-systemic vasculitis
-high fever
-abortions
-painful to move
-purple skin
-diamond skin lesions |
|
|
Term
| What can you do to prevent/control erysipelas |
|
Definition
-vaccinate every weaning
-quarantine
-good sanitation
-cull animals with joint lesions
-treat affected animals with antibiotics/water meds |
|
|
Term
| What makes the virus causing PRRSV such a severe disease? |
|
Definition
-can causes asymptomatic persistent infections
-can cause severe fatal disease
-replicates in macrophages
-considerable genetic mutation & recombination
-prolonged carrier state
-get lots of antigenic drift within the herd |
|
|
Term
True or False
There are multiple strains of PRRSV |
|
Definition
|
|
Term
| What percentage of herds in Ontario are infected with PRRSV |
|
Definition
|
|
Term
| How is PRRSV transmitted? |
|
Definition
body fluids
-needles, semen, trucks, flies, mosquitoes |
|
|
Term
| What are the clinical signs of reproductive PRRSV in pregnant sows |
|
Definition
-anorexia, fever, pregnant sow mortality
-minimal impact if 1st & 2nd trimester
-reproductive failure & infertility if >72 days gestation (transplacental infections) |
|
|
Term
| What are the clinical signs of PRRSV after transplacental infection has occured? |
|
Definition
-abortions
-premature farrowing (<110d)
-stillbirths, mummified piglets
-weak piglets
-neonatal diarrhea
-high pre-weaning mortality |
|
|
Term
| Describe the respiratory signs of PRRSV |
|
Definition
-dyspnea
-cyanosis of extremities (blue skin)
-minimal coughing unless 2ndary infection present
-immunosuppresive -> leads to other infections |
|
|
Term
| Describe the pathogenesis of PRRS |
|
Definition
1. Infection of tonsil & URT
2. Pneumonia
3. Alveolar macrophages destroyed -> 2nd lung infections
4. Decrease in lymphocytes, neutrophils
5. 2ndary infections e.g. neonatal diarrhea |
|
|
Term
| What should you do to treat PRRS? |
|
Definition
supporting treatment with anti-inflammatories
prevent secondary infections with strategic medication |
|
|
Term
| What can you do to control PRRSV in populations? |
|
Definition
Mass exposure
-vaccination *can revert to virulence!
Depopulation
-thorough clean & disinfect of barns 2x then repopulate with negative stock
Herd closure
-no incoming breeding stock for 6-12 months |
|
|
Term
| Why is PRRS a challenging disease to control? |
|
Definition
-many different strains, vaccines don't cross-protect
-transmission poorly understood
-immunity poorly understood |
|
|
Term
| If your cows are showing diamond skin lesions, what disease is present? |
|
Definition
|
|
Term
| What host factors contribute to erysipelas? |
|
Definition
|
|
Term
| What agent factors contribute to erysipelas? |
|
Definition
-survives well in dry environment
-susceptible to disinfectants
-toxin causes blood vessel damage |
|
|
Term
| What environment factors contribute to erysipelas? |
|
Definition
-unsanitary barn
-poor biosecurity
-carrier pigs present |
|
|
Term
| What is the link between PRRSV & enzootic pneumonia? |
|
Definition
PRRSV causes immunosuppression, damaging macrophages in the respiratory tract & reducing availability of neutrophils & lymphocytes
-increases risk of 2ndary infections such as mycoplasma hyopneumoniae |
|
|
