Healthy chickens have large, smooth combs that are bright red in color, elastic and warm to the touch. However, sometimes we find that the color of the cockscomb changes to a dark red, which may be due to the following reasons:
The dark red color of the cockscomb may be due to certain acute infectious diseases such as avian influenza, Newcastle disease, cholera or typhoid fever. These diseases can affect the blood circulation and metabolism of chickens, resulting in a darkening of the color of the comb.
Deficiencies in certain nutrients, such as vitamin A or B vitamins, can also cause a dark red color in the comb. These nutrients are essential for the health of the chicken's ** and mucous membranes, and their deficiency can lead to ** and mucosal lesions, which can affect the color of the comb.
The environmental conditions inside the coop can also affect the color of the comb. For example, environmental factors such as high humidity, poor ventilation, or the presence of harmful gases can cause irritation and damage to the chicken's respiratory system and mucous membranes, causing the comb to turn dark red.
Excessive startling or prolonged stress can also cause the comb to turn dark red. This is because the stress state causes the blood vessels of the cockscomb to dilate, increasing blood circulation, which changes color.