Chicks are very frail and vulnerable, especially during the first few weeks of their life. Hence, it is imperative to have sound management to keep your flock alive and healthy. However, early chick mortality cannot be completely avoided even if our management is robust and the quality of the chicks supplied is good, 1-5% of mortality is normal in a poultry farm; however, anything higher than this is a red flag and should be taken seriously.

A high mortality rate in a flock is a sure sign that something is wrong, and it demands the poultry owner’s immediate intervention and appropriate action to stop further losses. Many factors cause early chick mortality, these may include issues of genetics, management, disease and nutritional causes. In this article, we will look extensively at the causes of early chick mortality and ways by which we can reduce it.

What causes early chick mortality?

There are many reasons why chicks may die, the most common factors include:

•Genetics
•Management
•Nutritional
•Disease

Genetic causes

Genetic factors are primary contributors to early chick mortality. Inherited lethal gene mutations, congenital defects, and metabolic predispositions heavily impact hatchability and first-week survival rates.

Lethal gene mutations

Bird genomes contain several known lethal gene mutations. These genes typically cause developmental failures during the incubation period, leading to unhatched embryos or dead-in-shell chicks. In rare cases where a chick does hatch with these mutations, it often dies within the first 24 to 48 hours.

Congenital neurological defects

Certain genetic combinations cause neurological malfunctions shortly after hatching. Affected chicks may suffer from a failure to thrive due to an inability to reach food or water.

Congenital neurological defects manifest in the following ways:

1.Congenital Tremors: A genetic or sometimes viral condition causing severe, rhythmic tremors that prevent the chick from standing or eating properly.
2.Congenital Loco: Causes chicks to lose balance, walk in circles, or flip onto their backs, ultimately leading to starvation or trampling by other flock members.

Metabolic and cardiac predispositions

In meat-producing birds like broilers, rapid growth genetics can trigger lethal metabolic syndromes:

1.Sudden Death Syndrome (SDS): Often referred to as “flip-over disease,” it is linked to cardiac arrhythmias and is considered a metabolic disease where genetics, environment and rapid growth all play a role.

2.Ascites: Inherited fast growth creates a high demand for oxygen, causing heart and lung strain, which leads to fluid accumulation in the abdominal cavity and early death.

Skeletal and muscular deformities

Genetics, in combination with incubation conditions, can lead to structural defects. Chicks born with severe skeletal deformities (such as perosis, crooked toes, or twisted legs) often struggle to compete for feed and are highly susceptible to early culling or mortality.

Next month, we will look at management causes in early chick mortality.