"Identification and Causes of First-Grade Broiler Day-Old Chick Production: Quality Criteria and Influencing Factors"

Introduction
The quality of day-old chicks is a critical factor in the success of commercial broiler production. Grade A chicks not only exhibit higher survival rates but also demonstrate better growth uniformity, feed efficiency, and immune response. Accurate identification of these chicks during post-hatch evaluation, along with a clear understanding of the factors contributing to their production, is essential for improving productivity.

Characteristics of Grade A (or First-Grade) Chicks
General Appearance
The chick is alert and active, responding quickly to sound and movement. The eyes are bright and open, without any sinking or discharge. The beak is smooth and aligned, free from abnormalities.

Fluff Condition:
The fluff is dry, soft, uniform, and free of stickiness, indicating precise regulation of humidity and ventilation in the hatchery.

Closed and clean navel
The navel is fully healed, without any discharge or wounds, which is an important indicator of internal health and a reduced risk of navel infection (Omphalitis).

Abdomen is contracted and elastic
Complete yolk absorption is an indicator of proper circulatory system function and embryonic metabolism. Swollen or soft abdomens signal issues with absorption or temperature disorders during incubation.

Healthy locomotor organs
The legs are straight, without twisting or swelling of the hock joints. The toes are spread and aligned. Roughness or redness on the soles often indicates problems with the incubator floor or prolonged time spent inside the hatchery.

Appropriate and uniform weight
The chick’s weight should be approximately 67–70% of the egg weight before incubation. Uniformity of weight within the batch is of great importance.

Factors Influencing the Production of Grade A Chicks
1. Parent Flock Management

Balanced nutrition of the parent flock (calcium, phosphorus, vitamins A, E, B12, riboflavin) ensures eggshell quality and embryonic development.

Parent farm hygiene, disease control, and complete vaccination enhance passive immunity transfer to the chicks.

Flock age is also a key factor: young flocks produce smaller eggs, while older flocks lay larger eggs with variable quality.

2. Quality of Hatching Eggs

Proper size, healthy shell, and absence of cracks or surface contamination.

Storage at an appropriate temperature (15–18°C) and for a short duration (preferably less than 7 days) prevents a decline in hatchability rate.

3. Incubation and Hatching Management

Uniform temperature (37.5°C during incubation) and controlled humidity (55–60% during incubation, increasing to 70% in the hatcher).

Effective ventilation and CO₂ control inside the incubator prevent the occurrence of embryonic abnormalities.

Proper egg turning (5 times per hour) prevents the embryo from sticking to the shell.

4. Hatch and Delivery Timing

Chicks that hatch too early or too late experience metabolic problems, excessive dehydration, or incomplete yolk absorption.

Collection, vaccination, and transportation using standard equipment and optimal temperature