Neonatal immunity Flashcards
Complete development of the immune system requires…?
Antigen stimulation
What is essential for all veterinary species in the first few weeks of life?
Passive transfer of immunity from mother to newborn
What is the first foetal lymphoid structure?
Thymus
What develops at the same time as antibody production?
Cell mediated immunity
Following development of the thymus put the following in order of their foetal development:
- Peyer’s patches
- Lymph nodes
- Bone marrow, spleen
- Complement
- Blood lymphocytes
- Blood lymphocytes
- Bone marrow, spleen
- Lymph nodes
- Complement
- Peyer’s patches
What is the role of maternal hormones?
At birth they promote anti-inflammatory phenotype
- short lived
What are the 2 common infections that can occur during pregnancy?
- BVDV = bovine viral diarrhoea virus
- Neospora caninum
How do they effects of Neospora caninum change throughout the 3 pregnancy trimesters?
1st - absorption of mummified foetus
2nd - abortion
3rd - live calf with congenital infection
What are the two strains of BVD?
Non-cytopathic - doesn’t kill cells
Cytopathic - kills cells
Neonatal immunity is always what type of response?
Primary
Compare the Transfer of immunity to offspring in:
- dogs/cats
- ruminants, pigs, horses
- 5% placental, 95% colostral
- 100% colostral
How does colostrum provide immunity?
Active transfer of Igs from blood to mammary gland under hormonal influence
What is the main colostrum antibody?
IgG
As colostrum changes to milk get reduced IgG content, proportionally more … ?
IgA
What are important considerations surrounding the transfer of colostrum?
- Essential it happens in the first few hours of life
- Colostrum ingested and passes into GI tract where enzyme levels are low/blocked so that proteins can reach small intestine
- Newborns have a specialised Fc receptor on intestinal epithelial (only for up to 24 hours)
- In GI tract, Igs are bound, actively pinocytosed and quickly reach lymphatics and circulation
- So, in first few hours of life, newborn receives large amount of Igs from mother – rapidly seen in plasma Ig levels as maternally derived antibodies (MDA)