Neonatal Immunity And Colostrum Flashcards
Describe the development of the immune system in pocket Pete with short gestation periods
Mice(21 days), rats
Considerable development of the immune system AFTER birth
Describe the development of the immune system in larger pets/farm animals with long gestation periods
Dogs (63 days), cow (274 days), horse (340 days)
Immune system is nearly fully developed AT birth (still at high risk of disease since the adaptive immune system is naive-no memory, has had no exposure to pathogens so there is no memory cells to give a rapid response or preformed antibody in the blood at birth) but they have the frame work (lymphocytes, macrophages and dendritic cells (innate))
Response to antigens will be the same as in adults just no memory
Because a neonates adaptive immune system is developed by inexperienced, how does passive transfer aid in the first while of life
Dam provides protective antibody to keep the neonate healthy while the immune system develops
Passive because the immunity comes from the dam, and is not made by the neonates own immune system
Transferred via the colostrum or placenta
Describe the placental route of passive transfer in farm animals (all ruminants, pigs and horses)
Maternal blood cells separated by vascular endothelium, connective tissue and uterine epithelium, this results in NO placental antibody transfer
This makes colostrum essential for these animals
Describe the placental route of passive transfer in cats and dogs
There is SOME placental antibody transfer (10% of adult concentrations)
This makes colostrum very important to these animals
Describe the placental route of passive transfer in humans
Most of the newborns antibody is from the placenta, colostrum has only a small effect on the neonatal disease incidence
Describe the production of colostrum
Colostrum is the first secretion produced by the mammary glands of the common domestics species
It takes weeks to produce (not hours) in prep for birth (milk after wards is produced fast)
Antibody (especially IgG) is transported from serum into colostrum
The first 2 milking (suckings) are rich with antibody (true colostrum)
Describe the composition of colostrum
Rich in a variety of nutrients, lymphocytes and immune regulatory proteins
Colostrum is thicker and stickier and yellower than milk (has a higher specific gravity which is the basis for testing for colostrum quality)
What does having a high specific gravity mean
More “stuff” or solutes suspended in the liquid or solvent
Lactation beings
At parturition
As the neonate continues to suck from the dam, what happens to colostrum
Colostrum is replaced with milk and residual colostrum becomes diluted (transitions to milk for the first few days)
True colostrum changes to true milk
Milk has a much lower concentration of antibody, most are synthesized
In the mammary gland
Colostrum antibody is absorbed by the neonate resulting in passive transfer of immunity, what does this antibody do
Provides protection in the first weeks of life (until it is replaced or dies off)
What is failure of passive transfer?
Refers to the lack of significant absorption of colostrum antibody by the neonate
Neonatal digestive tract is undeveloped at birth, how does this aid in passive transfer
The undeveloped digestive tract allows large antibody proteins to be absorbed without being broken down
In what animals is failure of passive transfer most significant in
Farm animals since immunity depends completely on colostrum (no placental transfer)
True or false
If the mom is vaccinated, the colostrum will have those antibodies to give to the neonate
True
Without colostrum, what can occur
Slower growth
More infectious disease prevalence
More deaths
More deaths from hypothermia/hypoglycemia
True or false
Without receiving colostrum, neonates have a better response to vaccines?
True
Because there is no circulating antibody from colostrum to fight off the vaccine antigens (this is why the first serious of vaccinations is done with 3 successive rounds, to ensure it was not broken down by passive transfer immunity)
About ___% of dairy calves fair to attain adequate colostrum antibody
40%
These suffer more serious disease and are more likely to die