The immune system: how it builds up, from chick to adult
Why does an eight-day-old chick resist what kills a twenty-day-old chick? Why does the veterinarian set vaccines at precise ages and not when it suits you? Why does a flock that has been hot, thirsty or badly started fall ill three weeks later? The answer lies in an invisible system, the immune system, which builds up throughout the flock from an inheritance the hen left in the egg yolk. This lesson explains what you protect when you respect biosecurity and the veterinarian's calendar.
12 min read · 5-question quiz at the end
By Abdul Hussein ChoumanFounder of NEXTEKCI · Agnibilékrou hatchery since 2006Lesson reserved for students following the steps
This lesson is part of Level 6 — The bird: anatomy, physiology, behaviour. It opens to registered students who have passed the level 5 exam. Levels 1 to 5 and the tracks remain readable by everyone.
What you will learn
- ✓Name the chicken's three lines of defence and explain what each one does
- ✓Explain maternal immunity, how long it lasts and the 'window of fragility' it leaves
- ✓Understand why a vaccine takes 7 to 14 days to act and why the calendar belongs to the local veterinarian
- ✓Spot the six farm factors that weaken immunity and act on them