Enter the chicken coop and observe the flock carefully and find several problems:

  1. Most of the feces are black, accompanied by indigestion. Some feces are not formed and overfeed.
  2. Most cockscombs have hoarfrost, dander, or black crusts.
  3. The overall condition of the chickens is good, the spirit is normal, and there are no chickens with necks and eyes closed. There were also no respiratory symptoms.
  4. The quality of the eggs is very good, the color is bright, the shell is thick, and the size is uniform.
  5. The air quality of the chicken house is very good, the ventilation is good, there is no special smell, and it is not stuffy.

Two newly dead chickens were selected for autopsy and the following lesions were seen:

  1. The mesentery is black, the intestine is black, and the intestinal contents are light red.
  2. The ovaries are unchanged, the follicles are normal, and one of the chickens has an unborn egg (hard shell) in the fallopian tube.
  3. The glandular stomach is normal, and there are ulcers, cracks and erosions in the cuticle of the gizzard. Gastrointestinal bleeding.
  4. Other lesions are not obvious, and there are jujube-like protrusions in the intestines, which can be analyzed as individual phenomena, not as a basis for the overall problem of chickens.

According to this analysis:

  1. Black stool is caused by chronic bleeding in the gizzard. Because it is chronic bleeding and the blood volume is not large, it does not appear red stool. The blood passes through the intestines and mixes with the stool and turns black.
  2. Muscular gastric ulcer, erosion, hemorrhage, blackening of the mesentery, and blackening of the intestinal tract are all related to mycotoxins. This is also a chronic process and is not easy to detect. It is not easy to judge the appearance without dissection.
  3. There are dander, hoarfrost, and black scabs on the cockscomb, which are very common and are related to fungal infection. Although it does not affect feeding and egg production, it has an impact on the health of the flock and reduces the immunity of the flock.

According to feces, cockscombs, flock status, and anatomical lesions, it can be judged as:

  1. Adenomagastritis due to chronic infection with fungi and mycotoxins.

Because it is a chronic process and a latent infection, it is not easy to find. Muscle ulcers and erosions lead to indigestion, loss of feed nutrients, and incomplete absorption, so the egg production rate cannot reach 90%.