Animal Nutrition Quiz 2 Study Guide Feed Nutrient Analysis - TDN (total digestible nutrients)- o Measure of energy- comparable to digestible energy (DE)o Primarily used for ruminantso Expressed in units of weigh or percento TDN= (DCP+DNFE+DCF+2.25DEE)o Of tern under values protein o Used to balance rations- Protein utilization o Feed to gain being lower is a good thing. The less feed it takes you to get a greatergain the better. o Nitrogen cost us money we want less waste nitrogen- Protein Nutritive valueo Biological value (BV)- is just the % of nitrogen absorbed from the GI available for productive body functions BV=((N intake-[fecal N +urinary N])/(N intake – fecal N))x100o Protein efficiency ratio (PER)- number of grams of body weight gain of animal per unit of protein consumed.- Feed intake terms o Palatability – summation of animals differences to appearances, odor, taste, texture, temperature and other sensory properties. o Hunger- is based on a physiological need Satisfied by calories o Appetite- desire to repeat a pleasant experience Satisfied by palatability  Calories may not satisfy - Feed intake control o Long term (days and weeks)  Maintains energy balance (or nutrient accretion) in the animla depending on life stages  Hormone secretions like leptin (secreted by body fat stores) o Short term (hours)  Distension (neural receptors) GI hormones in response to nutrient absorption.  The fullness in the gut will tell us we aren’t hungry anymore (full) even if we haven’t met the nutrient need.o As digestibility increases distension stops the progression of everything elseGI Tract and Nutrition - GI- gastrointestinal- Purpose- provide the nutrients needed for use in the body metabolism and reject unnecessary or harmful substances - Primary functionso Digestiono Absorption of nutrients o Ingestion of food o Wastes removal (excretion) elimination o Secretion o Protection from toxicants/pathogens/etc. - GI tract regionso Mouth-  Starch digestion begins with salivary amylase Saliva production (buffering in ruminants) Chewing/mastication o Esophagus-the pathway to carry foodstuff from the mouth to the upper path of theGI tract. (in ruminants it also carries it backwards as well.)o Stomach Ruminant-- Reticulum o Microbial action (protozoa, bacteria. Fungi) o Anaerobic environment (no oxygen)o Almost all starch (cellulose/hemicellulose) is converted to VFAso Fat hydrolyzed and saturatedo Vitamin B-complex productiono Low quality protein/nonprotein nitrogen converted to high quality microbial protein o Waste products of fermentation: CO2, CH4 methane is produced as a way for hydrogen to escape the rumen since oxygen is not present. - Rumen o Rumination  Up to 8 hours a day  Controlled vomiting- Further chewing- More saliva production o Eructation  Belching of rumen gases  Bloat- pushing up against the diaphragm, causing breathing problems for the animal (can eventually lead to choking in the animal - Frothy bloat - Occurs with high quality early forages - Omasumo Water absorption o Digestion flow control - Abomasum (the true stomach)o Gastric stomach (acidic pH 4-5 range)o Pepsin/HCL production Begin protein digestion  Cardiac-mucus Fundus-pepsin/HCL, mucus Pyloric-mucus o Small intestine (absorbs more water than the large intestine)  Duodenum- Digestive secretions- Pancreatic secretions- Bile- Some absorption  Jejunum- Absorption  Ileum- Absorption o Cecum Ascending components  Larger in animals like the rabbit because it helps to break down the roughage they eat like veggies o Large intestine- Microbial digestion - Water absorption - Inorganic element excretion  Colon- descending components Rectum- short travel before the anus o Anus- route of exit from the body - Pregastrico Rumen (cow, sheep, etc)o Sacculated stomach (kangaroo) a pocket off of their stomach that allows for some microbial digestion but is not a separate structure from the stomach. o Prior to the abomasum there is a vat that contains microbes that are responsible for breaking down feedstuff. - Hind gut fermenters- receives less energy and nutrients from absorptiokn because of placement. o Cecum (rabbit, rat) o Sacculated colon (horse, pig)o Unsacculated colon (dog, cat) o Coprophagia- feces eating that allows them to recycle the energy that lost in the first round of digestion in the hind gut.- Nutrient utilization o Digestion  Mechanical forces (mastication/mixing)- the physical break down of the food (chewing)  Chemical action (HCL, bile) - In the stomach/ abomasum- Chemical breakdown of bonds in the feedstuff - Bile that is produced by the liver acts as an emulsification agent forfat- Emulsification- allows fat to suspend in water for further digestion to take place Enzyme action (hydrolysis)- Microbial action (rumen, colon, lg intestine) - Pepsin (stomach) - Amylase (mouth) o Absorption  Process of mobbing nutrients from GI lumen to the mesenteric blood or lymphatic system Some of this requires active energy some doesn’t o Metabolism  All the chemical processes in the body’s cells that provide for the growth , maintenance and production of the body. - Anabolic (synthesis)-glycogen - Catabolic (breakdown)- break down and make ATP (or something for the body)- Whatever is not utilized in metabolism for something will leave thebody as waste product.  Examples of metabolic processes/ pathways - Glycolysis/ gluconeogenesis- Protein breakdown/ synthesis- Lipolysis/ triglyceride synthesis - β-oxidation/fatty acid synthesis take special look at final slide of general flow of nutrients after a meal Carbohydrates - Fat is the long-term storage.- Carbohydrate is the short-term storage. So it is the first one used.- Two phases an animal is o Post prandial- you have just eaten a meal. The body has what it needs at that momento Meal- Carbohydrate- aldehyde or ketone derivatives of polyhydric alcohol’so Contains hydroxide groupso When these fold they fold differently based on the functional group present these shapes will affect the metabolic pathway - Classification and functionso Monosacccharde-1 sugaro Disaccharide- 2 sugar in chain (common table sugar)o Trisaccharide- 3 sugar in chain o Oligosaccharide- above 3 below 10 sugars in a chain o Polysaccharide- more than 10 in a chain - Polysaccharide o Importance Plant- (contains the greatest proportion of carbohydrate) - Cellulose-