In this article, I will explain about pigeon digestive system. The usual pigeon feed of seeds and grains consist of carbohydrates, fats, proteins, minerals, vitamins, etc. These nutrients must be made ready first for absorption in the blood. And circulation to all parts of the body for use to perform various functions. Although pigeons don’t have an elaborate system of taste. They can discriminate between a bad seed and a bitter one without crushing and tasting it. They usually leave old, moldy worm-eaten bad grain by merely looking at it, perhaps more by instinct than otherwise. It did only when there is sufficient time. And a lot to choose from but not when they are hungry and famished.
Procedure Of Digestion:
Due to inherent competition and struggle for existence, they scramble for food when they feed as a flock. In the latter case, pieces of wire and glass and even small nails took, thus endangering their innards. Therefore, the fancier must ensure an adequate supply of good and clean seeds, grains. or other feed in spacious feeders so that pigeons do not have to struggle and fight to feed. Let us see what happens to the food taken and processes involved in digestion and assimilation of seeds and grains, and the body parts involved in such procedures of pigeon digestive system.
The tongue is long and narrow. But broader and fringed at the base and lies on the mouth’s floor or the buccal cavity. It also carries taste buds, mostly on its upper side. Seeds and grains picked up by the beak and coated slightly with saliva are pushed forward by the tongue and swallowed by stretching. The neck and head and jerking into distensible tubing called the gullet esophagus open in the crop. Here these are softened with the help of water and get swollen to almost double their size.
The gullet is a wide enough expandable tube that can let pass the grains and seeds picked up by the beak on to the crop. The bi-lobed crop has no other function in non-breeding pigeons than to soften seeds and grains.
Bio-Lobed Crop: “Pigeon Milk”
In the breeding pigeons, the bi-lobed crop produces “Pigeon Milk” by both the cock and the hen, a feature that restricts the female sex; and very few other species of birds. Cells of the inner lining of the crop of both cock and hen commence dividing very rapidly, with the couple starting to sit to hatch eggs. The pace of cell division exceeds many folds in the last week of hatching. These cells get filled with fat and bud off and shed to constitute the “Milk,” which is a cheese-like cream-colored substance consisting of about one-third of solid matter and about three-fourths of water by weight.
A solid case is mostly made up of proteins. With considerable quantities of such minerals as calcium, potassium, sodium, phosphorus, and some essential vitamins. These nutrients, which are ready for assimilation. And necessary as the newly hatched chick’s digestive system requires time to start functioning and digesting food that consists of the normal softened grains and seeds fed by the parents. Artificial feeding of this “Milk” by research workers has produced accelerated growth in poultry chicks, indicating and confirming its importance for the newly hatched.
The pigeon drinks with its head pointing downward; Water gets sucked up before it drops down into the gullet and then into the crop. The crop is open in the proventriculus’ glandular stomach, which secrets some digestive juices, mostly hydrochloric acid and pepsins. The mixture then passes down into the gizzard or ventriculus to be ground to an excellent mesh. Walls around the small cavity of the biconvex muscular gizzard are very thick and tough and don’t get worn out, although very hard grit is invariably present in the feed. It is due to its rod-like keratinized cuticular lining. It added that grit helps promote and assist in grinding solid food by the gizzard to an excellent state.
Duodenum And Pancreas:
From the gizzard, finely pulverized food enters the first loop of the small intestine called the duodenum, which, in addition to secreting its juices, receives gastric juices from the pancreas that suspended in its loop; as well as from the adjacent liver. The middle part of the small intestine is called the jejunum, and the distal much-looped portion is the ileum. Whereas the pancreas and the small intestine provide enzymes essential for the digestion of carbohydrates, fats, and proteins.
The liver supplies bile for the digestion of fats. The entire small intestine’s inner surface study with a massive number of tiny projections called villi, which impart a velvet-like texture and increase its surface area immensely and help absorb nutrients in the blood. A very short large intestine follows the ileum. Their junction is marked by two caeca, which have no function to perform and represent degenerate vermiform appendix in man. The large intestine opens in the rectum of the same diameter. There is no distinction between the large intestine and the rectum that begins in the cloaca. Feces pass out through the anus.
Cloaca divides through membranes into several chambers with slightly different functions in the case of hens and cocks. In both sexes, the upper chamber receives ureters from the two kidneys depositing the solid uric acid or urea coated as a white cap on each dropping as it passes out of the body. In the hen, it also receives the egg. The lower chamber receives feces or the waste matter. Here it is further acted upon, and excess water and useful bacteria reabsorb in the system.
Diarrhea and excess water that some fanciers give by hand during hot summer competitions result in loose droppings with lost water and valuable bacteria, affecting the digestive system quite adversely. It also happens when the above chamber fails to perform its function correctly due to disease or infection. One finds the third chamber in very young chicks called bursa Fabricius connected with the growth process and disappears with age.
Food moves in the whole digestive system with smooth muscles of the elementary canal or the digestive system by a process called peristalsis.