Parts of a Chicken Digestive Tract
With crop impaction, even if a chicken continues to eat, the feed cannot pass the impacted crop. For example, passive absorption of nutrients such as fat-soluble vitamins is not subject to modulation by diet. It is usually rounder, but similar in structure to the proventriculus. When the flexor tendons are pulled taut, and the digits flexed, the tubercle pad moves proximally over the stationary plicae on the sheath. A bird can have as many as fifty bowel movements a day.
Birds gather and eat feed. The feed travels to the foregut esophagus, crop, proventriculus and gizzard where it is digested and prepared for absorption. Feed then travels to the midgut, or the small intestine. Here, nutrients begin to be absorbed. Remaining nutrients travel to the hindgut large intestine, ceca, vent and cloaca where waste is excreted. A healthy digestive system can be as simple as a balance of bacteria. Some birds ingest whole seeds that have not been shelled.
In cases like this, the gizzards power, along with some hard pieces of grit, break down the shell so the nutrient-filled insides can be processed. In the intestines, more juices are excreted. Bile and enzymes designed to break food down even more get to work on the food.
At the end of the line, some parts of the food cannot be used by the bird. This unusable food, along with waste products brought back from the bloodstream, come out of the bird as feces and urine.
All waste leaves the bird from the Vent or Cloaca. Since birds eat often and have such a high metabolism, they excrete waste often. A bird can have as many as fifty bowel movements a day. A Birds Digestive System. Because of the strong grinding motion of the gizzard's muscles, such sharp objects can put holes in the gizzard wall.
Chickens with damaged gizzards grow thin and eventually die. Preventing this situation is a good reason to keep a poultry house free of nails, glass shards, bits of wire, and so on. The small intestine is made up of the duodenum also referred to as the duodenal loop and the lower small intestine.
The remainder of the digestion occurs in the duodenum, and the released nutrients are absorbed mainly in the lower small intestine. The duodenum receives digestive enzymes and bicarbonate to counter the hydrochloric acid from the proventriculus from the pancreas and bile from the liver via the gall bladder.
The lower small intestine is composed of two parts, the jejunum and the ileum. The Meckel's diverticulum marks the end of the jejunum and the start of the ileum see Figure 6.
In the egg, the yolk sac supplies the nutrients needed for the embryo to develop and grow. Right before hatch, the yolk sac is taken into the navel cavity of the embryo. The residual tiny sac is the Meckel's diverticulum. Location of the Meckel's diverticulum in the digestive tract of a chicken. The ceca plural form of cecum are two blind pouches located where the small and large intestines join. Some of the water remaining in the digested material is reabsorbed here.
Another important function of the ceca is the fermentation of any remaining coarse materials. During this fermentation, the ceca produce several fatty acids as well as the eight B vitamins thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folic acid, and vitamin B Because the ceca are located so close to the end of the digestive tract, however, few of the produced nutrients are absorbed and available to the chicken.
Despite the name, the large intestine is actually shorter than the small intestine. The large intestine is where the last of the water reabsorption occurs. In the cloaca, the digestive wastes mix with wastes from the urinary system urates. Chickens usually void fecal material as digestive waste with uric acid crystals on the outer surface—that is, chickens do not urinate. The color and texture of chicken fecal material can indicate the health status of the chicken's digestive tract: The reproductive tract also exits through this area.
When a hen lays an egg, the vagina folds over to allow the egg to leave through the cloaca opening without coming into contact with feces or urine. These microflora aid in digestion. When chicks hatch, their digestive tracts are virtually sterile. If raised by a mother hen, a chick obtains the beneficial microflora by consuming some of its mother's fecal material.
In artificial incubation and brooding, chicks do not have this option. Through the probiotics, the chicks receive the beneficial bacteria they need to fight off infection by pathogenic bacteria, such as salmonella.