In Exercises 80 to 85, sketch the graph of g. a. | Ch 2 - 84

Non­Ruminant Mouth 1. Food Acquisition 2. Mechanical Breakdown (mastication) 3. Saliva  Add moisture  Buffer (bicarb)  Taste  Amylase (start starch digest) ­ ONLY primates and pigs Stomach (Monogastric)  4 regions  2 Secretions ­ HCI – Parietal Cells (pH~2.0) Chemical reaction NOT enzymatic ­ Pepsinogen – Chief Cells. In  pH  pepsin (active form) ­ Pyloric region regulates passage of feed (digesta) Small Intestine  Enzymes from S.I. and Pancreas   CARBOHYDRATES ­ Starch  glucose ­ Fiber  Fiber (not digested)  FATS ­ T.G.  glycerol & fatty acid   PROTEIN ­ True protein  amino acids (some not digested) ­ Non­protein  out. ~absorbed  MINERALS (absorbed)  VITAMINS (absorbed) Large Intestine  Water absorption ~ Minerals ~ Vitamins Ruminant Mouth  Food Acquisition ­ Tongue primary important  Mastication  No upper front teeth  Saliva ­ Add moisture ­ Buffer!!! ­ NO Amylase Reticulo­ Rumen  No enzymes from animal  Bacteria ~ 25­30 billion/mL  Protozoa ~200­500,000/mL  CARBOHYDRATES ­ Starch  microbe nrg  VFA ­ Fiber  microbe nrg  VFA ­ VFA absorbed from rumen wall ­ Main source of energy  FATS ­ T.G.  glycerol & fatty acids  PROTEIN ­ True Protein  microbial protein some by­pass goes to S.I. ­ Non­Protein N  Microbial protein  VITAMINS ­ B vitamins synthesized ­ Cobalt, cobalalmine Omasum  Water absorption Abomasum  True stomach  HCl  Pepsinogen  Pepsin Small Intestine  Major site of digestion & absorption by animal (digesta leaving rumen)  CARBOHYDRATES ­ Nothing, all in rumen  FATS ­ F.A. absorption  PROTEIN ­ Microbial protein  amino acids ­ By­pass protein  amino acid  MINERALS (absorbed)  VITAMINS (feed and microbial absorbed) Large Intestine  Water absorption ~ Minerals ~ Vitamins Young Ruminants  Essentially monogastric – Only abomasum fuctional  3 weeks: Rumen begins to become functional  3 months: (4 mo.) fully functional  Esophageal Groove: muscle, during first 3­4 months of life active. Nursing stimulates it closing – milk by­passes rumen and goes into abomasum. Terms  Regurgitate: to east up “digested” feed to the mouth.  Ruminate: Regurgitation, chewing, re­swallowing.  Eructate: Eliminating of gas via belching. ­ Gas produced by bacteria and protozoa ­ CO 2and CH 4 ­ Bloat = inability to expel gas  Swallow  Regurgitate  Chew bolus  Re­swallow  Another bolus regurgitated.  Rumination = Regurgitate  Chew bolus  Re­swallow Non­Ruminants Herbivores *See monogastric Non­Ruminant* Large Intestine  Cecum (pocket) ­ ~ Same as rumen ­ But CP (crude protein) No. ­ Starch No. ­ Fiber  VFA (Absorption) ­ B Vitamins Synthesized.  Rest of L.I. ­ Water Absorption ~ Minerals ~ Vitamins (B Vit.) Digestion of Cellulose  Pre­gastric digestion  Post­gastric digestion