The Chicken Digestive System Small intestine Aids in digestion and nutrient absorption. Made up of the duodenum, jejunum, and ileum. The chicken digestive tract is like other monogastric (single The largest glandular organ in the body. Aids in Liver stomach) animals such as pigs, horses, and dogs. The most notable differences in their GI tract are lack of teeth, crop, proventriculus, the metabolism of carbohydrates, fats, proteins, gizzard (ventriculus) ceca and cloaca. and sugars. Bacterial action which helps breakdown Ceca undigested food passing through the intestine. Labelled diagram of the chicken The ceca turn into the large intestine, which digestive system connects with the cloaca. Large Intestine To absorb water, dry out indigestible foods and eliminate waste products. Cloaca Where digestive, urinary, and reproductive systems meet. The external opening of the cloaca that passes Vent waste to the outside. A Ruminant Digestive System RUMINANTS: The process of digestion ~ 1. All herbivores (plant eating mammals) are called ruminants. Chickens do not have teeth. Therefore, mastication does not occur. 2. They chew the cud to breakdown plant matter and stimulate They simply swallow their food whole; it then passes down the digestion. oesophagus and into the crop where food is stored until it is ready to 3. The stomach is divided into four chambers – rumen, be passed into the proventriculus. This organ is the glandular reticulum, omasum, and abomasum. stomach where food is exposed to gastric juices, hydrochloric acid, Ruminants are animals with four-part stomachs which allows them and digestive enzymes. The gizzard is an organ with thick, muscular to chew food more than once (regurgitate). Examples of these walls that grind feedstuff into smaller pieces which makes digestion animals include sheep, goats and cattle which chew their cud easier. (ruminate). Cud is undigested vegetation which has been swallowed From the gizzard, food travels to the small intestine which consists and then ‘regurgitated’ back into the mouth for chewing. When it is of the duodenum, jejunum, and ileum. The duodenum is responsible swallowed again, the cud passes into the digestive system. for digesting proteins, fats, starch, and sugar. As such, the jejunum and ileum are primary sites for absorbing these nutrients. Undigested food enters the ceca which is a vast house for bacteria, yeast, protozoa, and fungi capable of digesting structural carbohydrates such as cellulose and Fiber. From the ceca food moves into the colon for water absorption. At this point, undigested food passes through the cloaca and exits the chicken. Parts of the chicken digestive system and function~ Parts Beak Function The process of digestion ~ Where food is picked up (pecking) and broken Through the action of rumination, ruminants ferment the food, up until able to swallow. Oesophagus Transports food from the beak to the crop. Crop A pouch in the oesophagus used to store food regurgitate, and chew their food before the main digestion process. 1. Ruminants quickly swallow the food and store it in the rumen. temporarily before passing into the 2. Once the rumen is filled, food passes into the second proventriculus. Proventriculus Gizzard chamber, (reticulum). The organ where food is broken down by gastric 3. In the reticulum, digestive juices partially digest the food. juices, digestive enzymes, and HCL. 4. The muscular part of the stomach that uses grit 5. Now when mammals are resting, they bring the cud back up to grind grains and Fiber in smaller pieces. Partially digested food is called cud. into the mouth for regurgitation. 1 6. After cud is chewed, food is passed to the omasum and the (one yolk) has matured it is released from the ovary into the oviduct abomasum. and its termed ovulation. 7. Symbiotic bacteria in the caecum brings about the complete digestion of cellulose. Processes of Rumination ~ Part of Length of Time spent oviduct part there Infundibulum 2 inches 15 min Function of part Picks up the yolk and Rumination is a complex process involving regurgitation, deposits it into the remastication, insalivation, and deglutition. magnum. Magnum Regurgitation – is the process by which partially digested feed 13 inches 3 hours Albumen is produced and returns from the stomach to the rumen to be remasticated. surrounds the yolk which Remastication – when the regurgitated feed is chewed again and forms the chalazae which break into smaller pieces. hold the yolk in a central Insalivation – is the process in which saliva is produced, mixed with position. Isthmus remasticated food to aid in digestion. 4 inches 1.25 hours Two shell membranes are placed around the egg. Deglutition – when remasticated food is mixed with saliva, swallowed, and passed to the rest of the digestive system to Uterus (Shell complete digestion. Gland) 4.2 inches 20.75 hours The shell, formed mainly of calcium carbonate, is deposited on the outer cell membrane. Four compartments and functions Vagina 4 inches 1-10 minutes The egg only stays here for Structure Function Rumen Storage of ingested food; addition a short time during which it of saliva to food. Digestion of is rotated through 180 cellulose by enzymes secreted by degrees so that it is laid at bacteria and protozoa. the large end first. Reticulum Omasum Vent/Cloaca Separation of larger pieces of food 4 inches The completed egg is for regurgitation to the mouth via expelled through this the oesophagus. opening. Storage of liquified food, muscular Structure of the Egg ~ contractions grind food into smaller pieces. Water and finer particles move to the abomasum. Abomasum Storage of liquified food; Chemical digestion of food by enzymes (proteins). The Reproductive Tract of a Hen ~ The egg structure is composed of shell, membrane, Air cell, egg white, egg yolk, and chalaza. The egg white forms 2/3rd of the whole whereas egg yolk covers only 1/3rd of the whole egg. The eggshell is hard and brittle and is either white or brown, it is composed of calcium, magnesium carbonate, and calcium phosphate. The Egg has: Two shell membrane which protects the inner parts against bacterial invasion. The reproductive tract of a hen is made up of two parts: the ovary Albumen (egg white) made up of proteins, minerals, water and for developing an embryo. and the oviduct. Ova (yolks) develop in the ovary. When an ovum 2 The air cell serves as a tiny shock absorber during early Folder – dried feedstuffs, such as hay, straw and chaff are used embryonic development. when forages are unavailable: can also include green chopped The chalaza holds the yolk in the centre of the egg. feedstuffs, such as corn stalks, elephant grass and kudzu. The yolk is a source of food for the embryo and contains fat Silage – pasture grasses, legumes and other crops conserved and in the egg. stored in silos. The germinal disc is where the female’s genetic material is Rabbit Production ~ found. Male Female Young The shell of an egg contributes to protection, respiration, and Buck Doe Kitten water exchange. Reasons for raising rabbits: The Vitelline membrane (VM) protects and vives shape to Food Clothes Incubation of eggs ~ Economic benefits Layer birds produce fertile eggs for hatching. Eggs selected for Pet/Comfort the egg yolk and separates it from the egg white. Breeds of Rabbits: hatching should be cleaned, of a good size, and shape. These can be hatched naturally by a broody hen or can be hatched artificially in an New Zealand White incubator. Eggs take 21 days to hatch. The egg in the incubator must New Zealand Red also have good circulation of air and a source of moisture to prevent Chinchillas them from drying out. Flemish Giant Californian White Candling Eggs ~ Mating Kindling Weaning In the process of candling, Eggs being incubated are carefully Signs of Heat: examined with the use of a candle to find out whether a dark area is Slimey discharge from Vulva. seen it means that an embryo is present. Swelling of the Vulva Making a lot of noise Humping other animals Feed Conversion Ratio ~ Feed Conversion Ratio (FCR) is efficiency with which the bodies of Mating – The doe will mate with the buck once she is in heat which livestock convert animal feed into the desired output (weight). means when she has produced eggs ready to be fertilized. 𝑡ℎ𝑒 𝑤𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑓𝑒𝑒𝑑 𝑖𝑛𝑡𝑎𝑘𝑒 Pregnancy – The gestation period for rabbits’ is 31 days. FCR formula = 𝑤𝑒𝑖𝑔ℎ𝑡 𝑔𝑎𝑖𝑛𝑒𝑑 𝑏𝑦 𝑡ℎ𝑒 𝑎𝑛𝑖𝑚𝑎𝑙 Kindling – The process of giving birth to kittens. Importance of FCR Helps control expenditure on feed Helps in identifying animals which are efficient feed Weaning – When kittens gradually give up milk for solid feed, this is usually after 8 weeks. Digestion in rabbits converters. A rabbit is an herbivore with a simple stomach. Rabbits are fed on: Selection of classes and breeds of animals that have low feed conversions. CLASS OF LIVESTOCK FCR AVERAGE CATTLE 4 : 5 to 5 : 0 : 1 PIG 3 : 5 to 4 : 0 : 1 GOAT 4: 5 to 5 : 0 : 1 RABBIT 3 : 0 to 3 : 5 : 1 CHICKEN 3 : 0 to 3 : 1 Herbage – water grass, sweet potato veins, lettuce, Spanish needle. Appropriate Rations for Livestock ~ Feedstuffs provide nutrients for energy, growth and development, maintenance, production, and reproduction. They can be classified into the following groups: Forages – green pasture grasses, legumes, mulberry and neem. 3 Root crops – radish, carrots, and sweet potato. Concentrates (pellets) Water A rabbit’s diet contains cellulose which is not broken down until membrane in mouth & food reaches the caecum. Undigested food passes into the small throat. intestine into the caecum and appendix where there are cellulose Fowl Typhoid digesting bacteria which breaks down and forms droppings which Coughing & Sneezing, green smelly droppings. are egested during the night. New Castle Difficulty breathing, Coprophagy – The habit of rabbits eating small droppings which Disease coughing, and sneezing. enables the animal to derive the greatest amount of nutrition from the ingested and re-ingested materials. Caring and Management of Rabbits ~ Like other farm animals, rabbits need a suitable diet to grow, develop and reproduce. An ideal diet consists of green feed, root crop, and commercial pellets with clean water. It is important to clean and sanitize the rabbits’ hutch to prevent diseases from affecting the animals. Their feeders and drinkers should be washed to prevent diseases. Diseases that affect rabbits ~ Disease Symptoms Treatment Coccidiosis Rabbits look sick with Add 16% dull eyes, droppings Sulfamezathine solution are loose/watery and in their drinkers for 5 bloody. days. Mammary glands The teat should be become swollen, hot, washed morning and and red. evening with warm Mastitis diluted antiseptic solution suitable for rabbits. Snuffles Coughing, sneezing, Remove animals from discharge of mucus drought free areas, small from nose. drops of eucalyptus oil in nostrils. Myxomatosis Swollen face, red Vaccination & Isolation eyes, pus, and swollen ears. Parasites Ear crank, irritated ear Isolate animals & soften scabs using cooking oil. Diseases in Chickens ~ Disease Symptoms Treatment Marek’s Legs stretched out Disease stiffly. Coccidiosis Diarrhoea, Blood in Add Sulphate faeces, sudden death of Mezathine to drinking young chicks. water and keep the Vaccination litter dry. Fowl Pox Breathing difficultly, Vaccinate non- cheesy yellow infected birds. Good Sanitation 4 Vaccination
