colostrum Flashcards
what is colostrum
- first milk produced after partuition
- very high in IgG (also IgM and IgA)
- IgG actively absorbed via GIT
how is maternal igG transferred into the neonate in rabbits and primates
ALL IgG transferred across the placenta
how is maternal iGg transferred into the neonate in dogs and cats
both in utero and via colostrum
how is maternal IgG transferred into cows, pigs, sheep and goats
all maternal IgG transferred via colostrum
why is colostrum important to neonates
- animals receiving IgG solely via colostrum are hypogammaglobulinemic (immunologically naive, immature innate immune system, increased susceptibility to disease)
- protects against hypothermia (have low % of adipose tissue and cannot thermoregulate properly)
why is colostrum important to neonates
gut health
- introcduces gut friendly microbes to stimulate the neonates immature digestive system
nutrition
- higher fat, protein, mineral and growth factor content compared to normal dam milk
immunity
- contains antibodies and other immune cells to reduce risk of infection and mortality rates
what is the role of IgG
only Ig that can cross the placental barrier and confer passive immunity. absorbed across GIT to provide systemic protection
- 85-95% Ig
what is the role of IgA
mucosal protection by prevention of pathogen attachment/colonisation and penetratin epithelial surfaces
what is the role of IgM
first to interact with pathogens and causes agglutination of bacteria when it binds to their surface epitope
how is colostral IgG absorbed by the GIT
- acheived by a process called pinocytosis
- cells engulf Ig’s from intestinal lumen and transfer across into lymphoreticular system
- enter the bloodstream intact (IgA later sent to mucosal surfaces, IgG remains in circulation
- IgG1 is re-secreted back into the GIT lumen
- pinocytotic cells have short life span and close at 24hrs of age
why is it crucial to get colostrum into the neonate as soon as possible after birth
- pinocytic cells have a short life span
- gut is completely closed after 24 hrs
- absorptive capacity of pinocytic cells is massively declined by 12-16 hours post birth
- important to get colostrum in by 6 hours post birth at MINIMUM (legal requirement)
- ability to absorb reduced by 30% 6 hours post birth
- concentration of mother’s colostrum IgG decreases exponentially over first 24 hours after birth
what is passive transfer
the process by which the neonate acquire immunity via absorption of immunoglobulina
what is the difference between successful passive transfer and failure of passive transfer
successful passive transfer = neonate consumes an adequate amount of immunoglobulins
failure = deprived of adequate colostrum
what are the 5 Qs of colostrum management
- quality
- quantity
- quickly
- quite clean
- quantify
list sources of colostrum
- dam
- fresh but different dam from same holding and same disease/vax hx
- stored refrigerated or frozen
- replacer (not supplement, ensure has enough IgG)
- different animal species (risk of hemolytic anemia in lambs)
list methods of delivering colostrum
- leave on dam (probably not sufficient for some)
- bottle feed (not bucket feed)
- tube feed
neonates left with to suckle dam are how many more times likely to receive insufficient antibodies
2.4 times
at what temperature should colostrum be fed
body temp (38 degrees)
or follow packet instructions
how should colostrum be stored
- 1-2L (dont pool)
- refrigerate at 4 degrees max 48hours post collection, ideally only 24 hours
- freeze for max 1 year and thaw at over 50 degrees
- pasteurize then store
what are the benefits of passive transfer
- short and long term health advantages
- reduces pre and post weanin mortality due to infectious disease
- increases daily live weight gain
- better feed efficiency conversion
- breeding animals have better fertility
- dairy cows, goats, and sheep have increase milk production in first and second lactation
what are the implications of failure of passive transfer
- short and long term health problems
- impacts on longevity
- increased risk of diseases (esp neonatal scours and spesis)
- increased risk of mortality
- stunted growth and development
how can you measure colostrum quality
- colostrometer (specific gravity directly related to IgG content)
- brix refractometer (measures protein fraction in colostrum to provide a decent correlation with IgG but not quantitiative
what is a suitable measurement of colostrum on a brix refractometer
22% = 50mg/ml immunoglobulin
discard anything below 22
how do you measure colostral antibody transfer
- brix refractometer can be used to measure protein fraction from a neonates serum sample
- foal IgG snap tests (over 800 mg/ml = good immunity)
can you correct failure of passive transfer
- serum transfusion (limited to valuable animals)
how does colostrum help to clear excess bilirubin from they body of a neonate
acts as a mild laxative to move meconium which helps clear excess bilirubin from the system
what factors can affect the quality of colostrum
- premature/induced birth
- breed and age differences
- length of non-lactation period
- time from birth to milking/striping milk from mother (if above 9 hours post birth, IgG level in solostrum have declined)
- dilution effect (dairy cows have higher milk yields than beef cows which can dilute IgG levels)
- disease at partuition
- poor BCS (no energy to produce good colostrum)
