w/c 30-June-14 Flashcards
(45 cards)
Where are leukocytes produced?
Bone marrow- all cell lines
Spleen and liver = potential to produce all leukocyte lines
Thymus, spleen, LN = most differentiation of lymphoid
Bursa of Fabricus function
Secondary lymphoid tissue in birds
Along with thymus, spleen and LN = differentiation of lymphoid cells.
When PCV tube is spun down, the layer where the leukocytes are is known as the…
Buffy coat. Is between the bottom layer (erythrocytes) and top layer which is the plasma
Why can’t leukocyte counts be done on a machine for reptile/avian blood?
Machine counts nucleated cells. Avian/Reptile blood=nucleated cells therefore falsely high.
Why do you get a neutrophillia from stress?
Neutrophils are ‘washed’ off their attached position on the blood vessel wall.
CNP to MNP Normal RATIO =
How does this differ between cats/dogs?
Circualting to Marginated neutrophil pool
Normally 1
i.e. same amount marginated as circulating but in CATS can be 3!!
therefore stress related neutrophillia
Neutrophil half life
5-10 HOURS
What is a left shift
If demand hgi, more immature neutrophils released i.e. MORE BANDS or earlier, known as a left shift.
When would you see toxic changes of neutrophils?
When they are being produced too quickly e.g. poorly developed nucleus or basophillia.
Cells can appear more blue or Dohle bodies might be present (all toxic change)
Difference between degenerate and toxic neutrophils
Degenerative neutrophils: In tissue, fighting with bacteria, bacterial toxins.
Toxic: in peripheral blood due to accelerated production. NO NEED FOR TOXINS!
Classification of regenerative left shift
Left shift: more immature neutrophil in circulation
Regenerative left shift = neutrophilia. Segemented > Bands
Classification of degenerative left shift
Left shift: more immature neutrophil in circulation.
Degenerative left shift: Neutropenia
Bands > Segemented
Significance of degenerative left shift
Severe condition. Start antibiotics!
Bands in circulation but still neutropenia.
Means dogs/cat have used up their storage pool
Horses/Cow significance of degenerative left shift
Horses and Cows don’t have the storage pool that dogs/cats have therefore tend to start off with a deg left shift (still need antib to help in first few days) then will tend to become regen after few days
Why is a degenerative left shift more severe in dogs/cats than large animals
Dogs/Cats have storage pool.
Horses/Cows don’t therefore start off with degen left shift while bone marrow inc production.
In dogs/ cats means it has used up storage and bone marrow is not keeping on top.
Both need antibs to start off.
Right shift is indicated by
Hypersegementation of the nucleus
Pet Travel Scheme (PETS) =
Required to protect individual pets but also UK disease status
Requires rabies and tape worm treatment but NO LONGER REQUIRES TICK TREATMENT (from Jan 2012)
Which tick born pathogens are endemic to UK (2) and how do they differ?
- Borrelia burgdorferi = Spirochete = Ixodes ricinus. Lyme disease
- Anaplasma phagocytiohillium = Rickettsial = Ixodes ricinus= Similar to E.canis but less severe
Which tick vector transmits Babesia canis/ Babesia gibsoni and Ehrlichia canis (all NON endemic to UK)
Rhipicephalus sanguineus
Ehrlichia canis: Rickettsial (causes Thrombocytopenia)
B. canis is more severe than B.gibsoni = PROTOZOAL
Large babesia / small babesia example
Protzoal.
Large babesia: B. canis
Small babesia: B. gibsoni (S. eruope)
V. uncommon in cats
Babesia pathogenesis
Within ticks, Babesia is transmitted trans-stadially and trans-ovarially.
Sporozoites injected from tick salivary glands
Enter circulation, endocytotosed by RBC
Immune-mediated
Cattle Babesia species =
Cattle and rodent reservoir are more important causes of human Babesiosis.
B. divergens = cattle.
Clinical signs of Babesiosis
Those of haemolytic anaemia:
Lethargy, Depression, Inappetence, Icterus, Splenomegaly, Tachycardia/Tachypnoea
Treatment of Babesiosis - does it differ between type of pathogen
Diagnosis: Microscopic identification (low sensitivity)
PCR or Serology (Ab test/ ELISA)
TREATMENT: Imidocarb diproprionate. Large forms (B. canis): Rapid clinical response Small forms (B. gibsoni) : Cure uncommon; relapses occur
