Learn why day-old and young chicks are highly vulnerable to diseases, the common causes, prevention methods, and practical tips for poultry farmers.

Why Chicks Get Easily Infected with Diseases

Raising healthy chicks is the dream of every poultry farmer. However, many farmers experience high chick mortality within the first few weeks after purchase. It is common to hear farmers say, “The chicks were healthy when I bought them, but after a few days they started dying.”

The truth is that young chicks have weak immune systems, making them highly susceptible to infections. Understanding why this happens is the first step towards preventing losses.

In this guide, we’ll explore why chicks easily get diseases, common mistakes made by farmers, and practical solutions suitable for poultry farming.

1. Chicks Have Weak Immune Systems

Just like human babies, newly hatched chicks are born with immature immune systems.

Although they receive some antibodies from the mother hen through the egg yolk, this protection only lasts for a short period. After which, the chicks must develop their own immunity. During this transition, they are highly vulnerable to diseases.

For example, a farmer purchases 100 day-old chicks from a hatchery. The chicks appear healthy, but after two weeks, several begin coughing and sneezing. This often happens because the maternal antibodies have reduced, and the chicks have not yet developed sufficient immunity.

2. Poor Brooding Conditions

Brooding refers to providing chicks with the correct temperature, ventilation, food, and water during their first few weeks. Poor brooding is one of the leading causes of disease outbreaks.

Common mistakes include:

• Low temperatures causing chicks to huddle together
• Excessive heat leading to dehydration
• Wet litter
• Poor ventilation
• Overcrowding

These conditions stress the chicks and weaken their immunity.

During the cold months, farmers sometimes underestimate how much warmth chicks need. Cold stress often leads to respiratory infections and increased mortality.

3. Dirty Drinking Water

Water is one of the quickest ways diseases spread.

If drinkers are dirty or contaminated with droppings, bacteria such as E. coli and Salmonella multiply rapidly.

Signs include:

• Diarrhoea
• Weakness
• Reduced feeding
• Sudden deaths

Clean drinking water should always be available.

4. Poor Quality Feed

Feed does much more than make chicks grow.

It also supports their immune system.

Low-quality feed may lack:

• Protein
• Vitamins
• Minerals
• Energy

Malnourished chicks become weak and cannot fight infections.

This can result from a farmer buying cheap, unbranded chick mash to save money. After several weeks, growth becomes uneven, and disease outbreaks become frequent because the chicks are not receiving balanced nutrition.

5. Lack of Vaccination

Vaccination is essential in poultry farming.

Many dangerous diseases have no cure but can easily be prevented through vaccination.

Common vaccines in Kenya include:

• Newcastle Disease
• Gumboro (Infectious Bursal Disease)
• Marek’s Disease
• Fowl Pox
• Infectious Bronchitis

Skipping vaccinations can lead to devastating losses.

6. Poor Farm Hygiene

Disease-causing organisms survive in:

• Dirty litter
• Feed spills
• Mud
• Standing water
• Equipment

Without proper cleaning and disinfection, infections spread rapidly.

Good hygiene significantly reduces disease risks.

7. Introducing New Birds Without Quarantine

Many farmers mix newly purchased birds with existing flocks immediately.

This increases the risk of introducing diseases.

New birds should ideally be quarantined for at least 14 days before joining the main flock.

8. Stress Weakens Chicks

Stress suppresses immunity.

Common stress factors include:

• Transportation
• Sudden weather changes
• Feed changes
• Loud noises
• Rough handling
• Overcrowding

A stressed chick is much more likely to become sick.

9. Biosecurity Is Often Ignored

Biosecurity means preventing diseases from entering the farm.

Simple practices include:

• Restricting visitors
• Using footbaths
• Cleaning equipment
• Controlling rodents
• Keeping wild birds away

Many disease outbreaks begin when these simple precautions are ignored.

Common Diseases Affecting Chicks in Kenya

Some of the most common diseases include:

Early diagnosis greatly improves management.

Practical Tips for Poultry Farmers

To reduce chick mortality:

• Buy chicks from reputable hatcheries.
• Follow the recommended vaccination schedule.
• Keep the brooder warm (32–35°C during the first week, reducing gradually each week).
• Provide clean drinking water daily.
• Feed high-quality chick mash.
• Replace wet litter immediately.
• Disinfect the poultry house before introducing chicks.
• Isolate sick birds immediately.
• Avoid overcrowding.
• Consult a veterinarian whenever unusual deaths occur.

Young chicks become infected with diseases easily because their immune systems are still developing. Poor brooding, dirty water, poor-quality feed, stress, inadequate hygiene, and failure to vaccinate all increase the risk of disease.

The good news is that most chick diseases can be prevented through proper management, good nutrition, timely vaccination, and strong biosecurity practices. Investing in these preventive measures is far more cost-effective than treating sick birds or replacing lost chicks.

For poultry farmers, paying close attention during the first six weeks of a chick’s life can significantly improve survival rates and overall farm profitability.