Neonatal immunity and colostrum Flashcards
Development of the immune system happens when
Develops in the fetus and or early neonatal life
When do pocket pets be considered immune system developed
Pocket pets with short gestation periods
Mice (21 days), rats
Considerable development of immune system after birth
When are larger animals immune system considered developed
Larger pets with long gestation periods
Dog (63 days), cow (274 days), horse (340 days)
Immune system nearly fully developed at birth
are the neonates of the common domestic species at special risk of infectious disease
Yes because the adaptive immune system is naive
What does naive mean?
No memory cells to grove a rapid, major, response
No preformed antibody at birth
What is in a naive immune system
The potential is present
Lymphocytes, macrophages, dendritic cells
For many antigens, the primary response is similar to that of adults.
Do neonates have innate immunity?
Similar to that in adults
What does the neonatal immune system need to be affective
They have a well developed adaptive immune system but is inexperienced
Needs exposure to pathogens to develop.
Memory
Production of circulating antibody
Passive immunity of neonatal
Neonates are protected in early life by transfer of antibodies from dam to neonate
Passive transfer of in neonates is and happens by
Dam provides protective Ig to keep the neonate healthy while its immune system develops
Passive because immunity is not made by neonate
Transferred via colostrum or placenta
Farm animals (all ruminants, pigs, horses) placenta transfer what
Maternal blood cells separated by vascular endothelium, connective tissue and uterine epithelium
No placental Ig transfer
Colostrum is essential
Cat and dog placental transfer of Ig
Some Ig transfer (10% of adult concentrations)
Colostrum is very important
Placental transfer of Ig from humans
Most of newborn’s Ig is from placenta, colostrum has only a small effect on neonatal disease incidence
Colostrum is
The first secretion of the mammary glands
Takes weeks to produce
Colostrum is rich in
Ig, especially IgG, is transported from serum into colostrum
Very rich in a variety of nutrients, lymphocytes, and immune regulator proteins
High in glucose
Colostrum looks like and is this way because
Colostrum is thicker and stickier (and yellower) than milk
Has a higher specific gravity
Basis of a test for colostrum quality
High in glucose
Colostrum vs milk
The first 2 milkings (and probably suckings in SA) are rich in Ig – true colostrum
Lactation begins at parturition
As the neonate sucks, colostrum is replaced with milk and residual colostrum is diluted
So, transition milk, produced for the first few days as change from true colostrum to true milk
Milk has much lower concentrations of Ig, most are synthesized in the mammary gland
Failure of passive transfer is
Colostral antibody is absorbed by neonate resulting in passive transfer of immunity.
The Ig provides protection in the first weeks of life
Failure of passive transfer refers to lack of significant absorption of cholesterol Ig by the neonate
Consequences of failure passive transfer
More infectious disease
More likely to die
Slower growth
Better response to vaccination
Most likely will die from hypothermia or hypoglycaemia
What percent of dairy calves have FPT
About 40% of dairy calves fail to obtain adequate colostral antibody.
Suffer more serious disease
More likely to die
What percent of calves will die when FPT
7% overall
10% of those that have FPT
How many beef calves will get FPT
6%