Karteikarten
Biosecurity, IBR and BVD
Karten in diesem Stapel (19)
- 1There are two main principles concerned with reducing the movement of infectious diseases. What are these called?1. Bio-exclusion
2. Bio-containment - 2Define Bio-exclusion.Bio-exclusion = activities to reduced the risk of introduction, to a population, of an external infectious agent
- 3Define Bio-containment.Bio-containment = activities to reduce the source and spread on an infectious agent from a farm population.
- 4What is normally considered the highest risk activity that would introduce infectious agent onto a farm?Buying stock
- 5Challenge and Immunity are the balance that decides whether an animals gets infectious disease or not. Explain what would happen with 1. Good defence and relatively low challenge? 2. High challenge and relatively poor defence?1. No disease
2. Disease - 6Control of any non-ubiquitous infectious agent should start with a...bio-exclusion risk assessment
- 7Bio-exclusion does not tend to be disease specific. What about bio-containment?Bio-containment is much more likely to be disease specific.
- 8What is the aetiological agent causing IBR? What are the three recognised subtypes of this aetiological agent?Bovine Herpes Virus 1 (BoHV1)
1. BoHV 1.1 causes IBR and can cause abortion
2. BoHV 1.2a causes IPV and can cause abortion
3. BoHV 1.2b causes IPV and CANNOT cause abortion - 9On BoHV 1 there are two glycoproteins of importance on its surface. what are these called and why are they important?There is glycoprotein E and glycoprotein B.
Cattle will raise antibodies to both of these glycoproteins and both of them are responsible for immunity. - 10In a primary infection of IBR what is the source of the virus and how is it spread?source of virus = other infected animals
spread of virus = mainly by direct contact (pen to pen disease)
Respiratory secretions as well as some reproductive secretions will contain virus. - 11Is it a primary or a secondary infection that is the only stage commonly associated with clinical signs of IBR? Clinical signs of IBR?Primary infection assoc with clinical signs.
1. Dullness and reduced appetite
2. Pyrexia
3. Sudden reduced milk concentration
4. Conjunctivitis
5. Nasal and ocular discharge
6. Tracheitis
7. Sometimes a cough - 12What happens all throughout primary infection of IBR?Shedding of virus to infect others until animal produces an immune response and becomes clinically normal again. Virus is localised to nerve ganglia and becomes latent.
- Paired antibody rise to gE and gB. it is a sustained Ab response due to latency. - 13What stimulates reactivation of latent IBR infection?STRESS!
- calving
- transport
- high steroid tx
- Lameness, disease, nutritional stress - 14Upon reactivation of a latent IBR infection what happens?1. Virus is shed (less than during primary infection)
2. Clinical signs are absent or very mild
3. Antibodies against gE and gB are restimulated - 15What is a sero-negative latent carrier of IBR?An animal who became infected during period of maternally derived anibody cover - so animal becomes latently infected without circulating antibody. MDA prevents clinical disease and seroconversion.
- 16Tx of IBR?1. NSAIDs
2. Rest
3. Abs only if you consider animal at risk of contracting secondary infection.
4. Consider vaccination of the rest of herd if have confirmed diagnosis. Live Vax which is intranasal. - 17Diagnosis of IBR in the acutely sick animal?In the acutely sick animal
1. DIRECT TEST - looking for virus itself. Occular conjunctival swab and guarded nasopharyngeal swab. The lab will then carry out PCR or virus isolation. - 18Diagnosis of IBR at a herd level?SEROLIGICAL ANTIBODY TESTING
tests for antibodies to gE or gB. Serology is an essential for the control of IBR in the herd. - 19—
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- Beschreibung
- BVMS 4 Cattle Karteikarten am Biosecurity, IBR and BVD, erstellt von Holly Wark am 29/03/2016.
- Erstellt von
- Holly Wark
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