RUMINANTS! Agriscience I. Introduction A. What do these animals have in common? 4 compartment stomach B. What does this anatomical feature permit the animals to do? Digest plant material (plant fiber or cellulose) C. Facts about ruminants 1. We (humans) and preditors cannot eat 99% of plant material on earth’s surface. 2. We cannot digest the plant material that we do eat. 3. Ruminants convert plant material to food products for us: a. They eat and digest plants b. We consume meat and milk products c. We use products made from fat and bone d. Predators have a food source 4. 90 Percent of world’s plant-eaters are ruminants D. What makes the ruminant system suitable for plant eaters? 1. They eat grass, shrubs, and trees 2. When threatened they run (fight or flight) 3. Observe a deer eating in an open field (always on high alert) 4. Ruminant system permits plant eaters to: a. Fill up fast and go to a safe place to digest b. Store large amounts of food while available and digest later

Ruminant Digestion Agriscience Anatomy Process Physiology Development E. Today 1. Ruminant Basics 2. Ruminant anatomy and digestion - video 3. Calf digestive tract development - models 4. Rumen exploration - canulated steer 5. Rumen fluid sample - collect and analyize in lab under microscope

Mammalian Digestive Systems Agriscience Monogastric Equine Ruminant All mammals have one of three basic types of digestive systems Whilethey are all similar, there are some variations within each type

Monogastric (Simple Stomach) Agriscience Humans, pigs, predators One compartment Glandular design II. Mammalian Digestive Systems A. Monogastric 1. Humans, pigs, and predators 2. One small, simple stomach compartment 3. Glandular design 4. Secretes acid and enzymes that digest food to its most basic chemical compounds. 5. Monogastrics cannot digest plant fiber (cellulose) 6. Monogastrics need concentrated, high energy diets

Equine Agriscience Horses and their relatives One glandular compartment Hind-gut fermenter (cecum) to digest plants Agriscience II. Mammalian Digestive Systems B. Equine 1. Horses and relatives, gerbals 2. One simple, glandular stomach 3. Hind-gut fermenter between small and large intestines to digest plant fiber (Cecum) 4. Cecum contains bacteria which break down cellulose 4. Must grazefairly often and must have fiber (grass or hay)

Ruminant Agriscience Most herbivores Four compartment stomach Fore-gut fermentation vat to digest plants Agriscience II. Mammalian Digestive Systems C. Ruminants 1. Most herbivores 2. Fore-gut fermentation vat 3. Four compartment stomach (no four stomachs) 4. One compartment is a glandular stomach 5. Other three compartments break down cellulose and prepare ingesta for complete chemical digestion. 6. System is based on anaerobic fermentation by bacteria

Nature’s Amazing Plant-Digesting Machine The Ruminant Nature’s Amazing Plant-Digesting Machine Agriscience The ruminant is an organism with a very complex and amazing structure which permits it to utilize the most common food source on the planet: plants

I thought Dumbo was an elephant Ruminant Facts (Bovine) Chews cud 40,000-60,000 jaw movements/day No upper incisors - dental pad Does not “bite” grass - wraps tongue Uses fermentation to digest plants Symbiotic relationship with bacteria Produces 13 gallons of gas/hour Produces 40 liters of saliva/day Does not sleep! Agriscience I thought Dumbo was an elephant III. Ruminant A. Ruminant Facts 1. Chews cud 2. 40,000-60,000 jaw movements/day 3. No upper incisors - dental pad 4. Does not “bite” grass - wraps tongue 5. Uses fermentation to digest plants 6. Symbiotic relationship with bacteria 7. Produces 13 gallons of gas/hour (carbon dioxide and methane) 8. Produces 40 gallons of saliva/day 9. Does not sleep! 10. Symbiotic relationship with bacteria a. Bacteria digest cellulose for the cow b. Cow provides for the bacteria: 1) Home with reliable heat 2) Waste removal 3) Adequate nutrition 4) Ideal pH

Stomach Compartments Agriscience Rumen - fermentation vat Reticulum - rumen’s “assistant” Omasum - dehydrator Abomasum - glandular stomach Agriscience Four compartments are “crammed” together inside the abdominal cavity. Oriented so that rumen is on cow’s left side, reticulum in front near chest, and omasum/abomasum on cow’s right side. Rumen + Reticulum = Reticulorumen

Rumen Agriscience Largest compartment On left side of animal Contains micro-organisms Ferments cellulose Absorbs VFA’s Divided into chambers Continually contracting Contains papillae Produces CO2 and CH4 pH close to neutral (6 - 7) Agriscience IV. Stomach compartments A. Rumen 1. Largest compartment (up to 40 gallons in mature cow) 2. On left side of animal 3. Contains micro-organisms a. 500,000 billion bacteria (5 X 1015) - 5 quadrillion b. 50 billion protozoa 4. Ferments cellulose 5. Absorbs VFA’s (short chain FA’s - acetic, proprionic, butyric) 6. Divided into chambers called sacs 7. Continually contracting (motility) - 1-3 per minute in healthy cows 8. Lining itself not absorbant (squamous epithelium) 8. Contains vascularized papillae 9. Produces CO2 and CH4 10. pH close to neutral (6 - 7)

Reticulum Agriscience Smallest compartment Lies close to the heart Small sac - part of rumen body Catches dense, heavy feed for later rumination Contracts for regurgitation “Honeycomb” lining Catches hardware and stores it Agriscience IV. Stomach compartments B. Reticulum 1. Smallest compartment 2. Lies close to the heart 3. Small sac - part of frontal rumen body near esophagus 4. Catches dense, heavy feed for later rumination 5. Contracts for regurgitation a. Contractions (secondary) push dense, heavy feed back up the esophagus for cud-chewing. B. Feed pushed up for rumination called a bolus 6. “Honeycomb” lining 7. Catches hardware and stores it indefinitely

Omasum Agriscience Third compartment Globe-shaped Lining called “many plies” Reduces feed particle size Absorbs water and dries out ingesta Absorbs volatile fatty acids IV. Stomach compartments C. Omasum 1. Third compartment 2. Globe-shaped 3. Lining called “many plies” 4. Reduces feed particle size 5. Absorbs water and dries out ingesta 6. Absorbs volatile fatty acids

Abomasum Agriscience Final compartment Tubular in design “True” stomach (glandular) Secretes HCl and enzymes for chemical digestion Reduces pH to 2.5 Dissolves minerals Kills rumen bacteria Breaks down proteins Passes ingesta to small intestine Agriscience IV. Stomach compartments D. Abomasum 1. Final compartment 2. Tubular in design 3. “True” stomach (glandular) 4. Secretes HCl and enzymes for chemical digestion 5. Reduces pH to 2.5 a. Dissolves minerals b. Kills rumen bacteria c. Breaks down proteins 9. Passes ingesta to small intestine

Ruminant Digestion Agriscience The process of digestion by ruminant is very involved and complex (much more than monogastrics) Very intricate systems There are many things which must happen in the proper order There are many things which can go wrong Bloat Acidosis Displaced abomasum Ketosis

Ruminant Digestion Agriscience Rumination Intake Mastication (chewing) Swallowing Regurgitation Remastication Fermentation Eructation Absorption Digestion Rumination Agriscience V. Ruminant Digestion A. Intake 1. No upper teeth - dental pad 2. Cows wrap tongue around grass and tear (sheep bite) B. Mastication (chewing) 1. Reduces particle size 2. Mixes with saliva to begin digestion C. Swallowing 1. “Light” grasses and seeds pass directly to rumen 2. Heavy, dense feeds & large particles fall into reticulum 3. “Hardware” falls into reticulum D. Regurgitation & Remastication (Rumination) 1. Heavy feed and large particles pushed back up the esophagus by reticular contractions. 2. Feed is rechewed to further reduce particle size and add more saliva 3. Rumination occurs 10-12 hourse per day. E. Eructation 1. Rumen gases released into atmosphere by belching 2. Gas travels up esophagus at up to 7.3 feet/second (llama spit) 3. Anthing that interferes with eructation causes bloat and can be fatal because expanding rumen takes up space for lungs, squeezing air out, preventing inhalation, and animals suffocates. F. Absorption 1. VFA’s are passed into bloodstream in rumen and omasum 2. Water is absorbed from ingesta in omasum G. Digestion 1. Abomasum mixes enzymes and HCl with ingesta 2. pH 2.5 kills rumen bacteria and protozoa that get through 3. Feed reduced to basic chemcial compounds in abomasum and S.I. 4. Nutrients passed into bloodstream through abomasum walls and small intestine

Fermentation Agriscience Anaerobic bacteria break down cellulose VFA’s released by bacteria passed to bloodstream through papillae CO2 and CH4 produced by bacteria Bacteria controlled by protozoa Ingesta passed to omasum by contractions Agriscience F. Fermentation 1. Anaerobic bacteria break down cellulose 2. VFA’s released by bacteria passed to bloodstream through papillae (Acetic, Proprionic, Butyric) 3. CO2 and CH4 produced by bacteria 4. Bacteria controlled by protozoa 5. Ingesta settles and becomes more liquid as fermentation proceeds 6. Ingesta evenutally passed to omasum by primary contractions (1-3 per minute)

Calf Digestive Tract Development Agriscience Calves are an investment They must be fed properly as babies to insure they develop properly You must understand the development of the digestive tract in order to properly feed calves.

Calf Digestive Tract Development Newborn Agriscience Only abomasum is functional Sucking action forms esophageal groove Milk passes directly to abomasum Milk curdles and digests slowly Rumen does not develop as long as calf is on milk only VI. Calf Digestive Tract Development A. Newborn 1. Calf is born with a stomach in which only the abomasum compartment is functional. 2. Rumen, reticulum and omasum do not work at first 3. Nourishment (milk) must go directly to abomasum 4. Sucking action causes folds of muscle in rumen to contract and form the esophageal groove 5. Milk bypasses rumen and abomasum and goes directly to abomasum 6. Milk coagulates (curdles) in abomasum to form a “curd” which digests slowly 7. Rumen does not develop properly as long as calf consumes only milk 8. Stomach size a. 60% abomasum - 4 liters b. 25% rumen - 1.7 liters c. Total size - 6.7 liters Abomasum - 4 liters Rumen - 1.7 liters Total Size - 6.7 liters

Calf Digestive Tract Development 12-16 Weeks Agriscience Feed (grain) consumption causes rumen to develop Rumen is populated with micro-organisms from environment Bacteria produce VFA’s which cause rumen to develop papillae and increase in size Calf can digest hay and grass once rumen develops Calf Digestive Tract Development A. 12 - 16 weeks 1. As soon as calf begins to eat grain feed the rumen begins to develop 2. Rumen is populated with micro-organisms from its environment (microbes are everywhere) 3. Rumen bacteria release VFA’s which cause papillae to develop 4. Only grain contains VFA butyric acid, which is needed for rumen development (grass & hay does not contain butyric acid) 5. Once papillae develop calf can digest cellulose 6. Calves should be fed grain feed as soon as possible after birth. Abomasum - 4 liters Rumen - 13 liters Total Size - 20 liters

Rumen Exploration Agriscience Agriscience Lab Lab will involve investigating rumen and taking a fluid sample Lab also will involve listening to rumen contractions using stethoscope

The Cannula Agriscience Provides direct access to the rumen Possible only in ruminants Rumen wall is very close to epidermis behind the ribs on the left side Surgically inserted by a veterinarian Not painful or dangerous to the cow Permits researchers to: Observe rumen function Evaluate digestion of different feedstuffs Remove fluid to use as inoculant for sick cows Agriscience VII. Rumen Exploration A. The canula (fistula) 1. Provides direct access to the rumen 2. Possible only in ruminants 3. Rumen wall is very close to epidermis behind the ribs on the left side 4. Surgically inserted by a veterinarian 5. Not painful or dangerous to the cow 6. Permits researchers to: a. Observe rumen function b. Evaluate digestion of different feedstuffs c. Remove fluid to use as inoculant for sick cows

Rumen Investigation and Sampling Agriscience Put on obstetrical glove Remove cannula lid and permit gas to exit Feel rumen wall and papillae Reach into ingesta Pick up ingesta (liquid and solid) Collect a fluid sample VII. Rumen Exploration B. Investigation 1. Put on obstetrical glove 2. Remove lid and permit gas to exit 3. Feel rumen wall and papillae 4. Reach into ingesta 5. Pick up ingesta (liquid and solid) 6. Collect a fluid sample

Rumen Fluid Evaluation The Rumen Contains: Bacteria (digest cellulose) Over 200 species Smaller than 5 microns (5/1000 mm) Can only be seen with an electron microscope Protozoa (control bacteria population) Much larger (20-200 microns) Can be seen with microscope at 400X Prey on bacteria Fungi (aid in cellulose digestion) Same size range as protozoa Numbers are very low in rumen Discovered only 20 years ago Agriscience VII. Rumen Exploration C. Rumen fluid contents 1. Bacteria (digest cellulose) a. Over 200 species b. Smaller than 5 microns (5/1000 mm) c. Can only be seen with an electron microscope 2. Protozoa (control bacteria population) a. Much larger (20-200 microns) b. Can be seen with microscope at 400X c. Prey on bacteria 3. Fungi (aid in cellulose digestion) a. Same size range as protozoa b. Numbers are very low in rumen c. Discovered only 20 years ago D. If microorganisms die en masse due to a rumen problem, the rumen shuts down and the cow will die.

Rumen Fluid Evaluation Place a drop of fluid on a slide Position cover slip Place under microscope Locate fluid smear at low power Increase to 400X and adjust light Agriscience VII. Rumen Exploration D. Rumen fluid evaluation 1. Place a drop of fluid on a slide 2. Position cover slip 3. Place under microscope 4. Locate fluid smear at low power 5. Increase to 400X and adjust light

Rumen Microorganisms Dasytrich and Entodinium protozoa Large protozoa Isotrich and Entodinium protozoa Fungal sporangia

To Comply With Unapproved and Extra-label Drug Use Rules Agreement To Comply With Unapproved and Extra-label Drug Use Rules Of the Georgia Junior Livestock Program By signing this agreement I acknowledge and agree to the following: I am a bona fide member of the Morgan County FFA Chapter. I understand that the Georgia Department of Agriculture may conduct random urine drug tests on all species at the livestock shows beginning in 2004. I have read and/or had explained to me the rules regarding unapproved and extra-label drug use in animals participating in the Georgia Junior Livestock Program and agree to abide by the following: I agree not to give a show animal any medication not specifically labeled for it according to its species, age, time to slaughter, or stage of lactation. I agree not to exceed labeled dosages when giving animals over-the-counter medication or medication prescribed by a veterinarian. I agree not to give a show animal prescription medication unless that animal is under the care of a licensed veterinarian. If I have an animal under the care of a veterinarian and am administering medication according to the veterinarian’s instructions I agree to have the prescription in my possession while my animal is on the premises of a show. I understand that a prescription does not necessarily mean that my show animal is automatically in compliance with the rules if a urine test reveals a specific violation. I agree to abide by withdrawal times of medications and/or feed additives. I will not bring an animal to a show that is within the withdrawal window stated on the medication and/or feed additive’s label. I agree to notify Mr. Savelle of any medications that my show animal is receiving as soon as I begin administering the medication. I understand that violation of the rules on unapproved and extra-label drug use in animals that I exhibit in the Georgia Junior Livestock Program may result in fines, disbarment from exhibiting livestock at junior shows in the future, and possible legal action against myself, my parents, and my agriculture teacher. I have participated in a class offered by my FFA chapter in which I was made aware of the rules governing unapproved or extra-label drug use by the Georgia Junior Livestock Program. Signature of Student Date: Signature of Parent/Guardian Signature of Agriculture Teacher/FFA Advisor

Agriscience