Nutrition (ANISCI EXAM #1)

water

ongoing loss of water: saliva, urine, sweat, milk

ongoing need for water: gives body shape, ttransports nutrients, participates in metabolic relations, eliminates waste and excess heat

grass 85% water → drink less water

hay 85% dry matter → need MORE WATER

carbohydrates

major energy source and easily digestible

1) simple carbohydrates → easy to digest

• sugar (glucose), in cereal grains: wheat, oats, barely, rye

2) complex carbohydrates → more slowly digested

• main source of energy for poultry and swine

3) dietary fiber→ difficult to digest

• require host & microbial interaction

• cellulose, lignin, hemicellulose

• main energy source for ruminants and hindgut fermenters

lipids

• structure: carbon + hydrogen > oxygen

• ENERGY

• essential fatty acids, fat soluable vitamins (A, E, D, and K)

• easy to digest

• triglyceride + water = glycerol + 3 fatty acid chains

Free Fatty Acid (FFA) = Nonestrified fatty acid (NEFA)

protein

• chains of amino acids (carbon, hydrogen, oxygen, NITROGEN, ± iron, phosphorus, sulfur)

• must have nitrogen in it

• excess protein → energy

• animals need diff amounts of protein based on their age + activity level

classification of proteins

essential amino acids

• must be supplied in diet

• different for each animal

semi essential amino acids

• slowly produced in the body from other amino acids

non essential amino acids

• produced by animal as long as it has the elements

dry matter (DM)

feed w all moisture removed

• determined by heating feed until all water has evaporated

converting DM to As Fed basis to feed

desired weight of DM/actual DM of feed = actual weight of food

crude protein

true protein + non protein nitrogen

avg protein = 16% nitrogren

crude protein = total protein x 6.25

path of food

Mouth (+ salivary glands) →esophagus →stomach → small intestine - duodenum, jejunum, ileum (+ pancreas - bicarbonates, enzymes + liver -bile stored in gallbladder), large intestines - cecum +/- colon → rectum

Monogastrics

• 1 stomach

• acid and digestive enzymes

• depend primarily on concentrate feeds

  • <18% crude fiber on a DM basis

ex. pigs, dogs, cats, humans

Herbivore, Monogastric Hindgut fermenter

microbial breakdown and fermentation of forage (>18% crude fiber) occurs after the stomach in the cecum and/or large intestines

ex. horses

• duodenum, ileum, right ventral colon, left ventral colon, left dorsal colon, right dorsal colon, transverse colon, small colon, rectum

herbivore, ruminant, foregut fermenter

cow stomach → forestomach, true stomach

forestomach: rumen (40-60 gal), reticulum (2-5 gal), omasum (4-15 gal)

“true” stomach: abomasum (4-7 gal)

carbohydrates in feed

structural “cell well” neutral detergent fiber + nonstructural “cell contents” → broken down through MICROBIAL FERMENTATION & DIGESTION

structural cell wall neutral detergent fiber - ex. cellulose, hemicellulose, lignin

nonstructural “cell contents” - ex. sugars and starches

products of microbial fermentation and digestion

1) volatile fatty acids: propionic acids, butyric acid, acetic acid

2) methane and carbon dioxide →expulsion of gases through eructation(burping)

3) lactate

volatile fatty acids

acetic acid, butyric acid, propionic acid

• provide up to 80% of ruminants energy needs

acetic acid - volatile fatty acid

• fatty acids

• muscle metabolism

• body fat

• milk fat

butyric acid - volatile fatty acid

• energy for rumen wall

• converted to ketone = B-hydroxybutyrate (B-HBA) used for fatty acid synthesis

propionic acid - volatile fatty acid

LIVER = made into glucose (energy!) and lactose

Energy Balance

Feed → Rumen ( volatile fatty acid’s → propionic acid) → Liver (oxaloacetate) →glucose (energy)

Minerals

purpose: components of bones and teeth and an important part of body’s enzymes

• elements other than C,H,N,O → INORGANIC

most feeds contain some sort of minerals

• supplemental minerals provided in the form of salt, trace mineralized salt, bone meal etc

macrominerals vs microminerals

macro → required in larger amounts

ex: calcium, phosphorus, magnesium, sodium, chloride, potassium, sulfur

micro → required in smaller amounts

ex: copper, iron, selenium, zinc, cobalt, fluorine, iodine, manganese, molybdenum

deficiency vs toxicity

deficiency : not enough of a mineral

toxicity or poisoning : too much of a mineral

Vitamins

• organic (carbon-containing) nutrients

• needed in very small amounts for specific functions

fat soluable vitamins

involved in regulating body functions (vision, blood clotting, tissue maintenance) and growth (bone development)

• need to be supplied in diet for all species

  • except vit D which requires exposure to sun and vit K in ruminants which is synthesized by microbes

water soluble vitamins

used more for body metabolic regulation

vitamin C and B-complex vitamins

vitamin A

pigment in the retina, reproductive ability, immunity

vitamin D

sun → skin → liver → kidney → Ca absorption in the intestines

important for bone growth and repair

lack of vit D → rickets

vitamin E

antioxidants, cell signalling, neurologic functions, reproduction

vitamin K

blood clotting

• ruminants synthesize this by microbes

vitamin C and B-complex vitamins

vitamin C (ascorbic acid) - aid teeth/bone formation and infection prevent

• lack of vitamin C = scurvy

B-complex vitamins - involved in chemical reactions, improve appetite, growth and reproduction

• choline, B1, B2, B6, biotin, niacin, B12, panthothenic acid

water soluble vitamins in ruminants and horses

ruminants: microbes supply all water soluble vitamins except for vitamin C and choline

• choline produced in liver

horses: microbes in cecum produce B vitamins

polioencephalomalacia

vitamin B1 (thiamine) deficiency

vit B1 acts as a cofactor for several key enzymes involved in glucose metabolism

• needed for proper brain function since the brain relies on glucose as major energy source

Forage/Roughage

high fiber, hard to digest, >18% crude protein

fresh: pasture, green chop

dried: hay, straw

fermented: silage

legumes vs nonlegumes

legumes: CONTAINS NITROGEN → MORE PROTEIN, nodules on roots are able to take nitrogen from air and turn it into ammonia which converts into ammonium

ex. clover, alfalfa

nonlegumes: CONTAIN LESS PROTEIN, can not use nitrogen from the air

concentrates

low fiber, highly digestible, < 18% crude fiber when dry

energy feed: grain & by products

protein: animal or plant

concentrates → protein supplements (> 20% protein)

animal proteins: > 47% crude protein, more balanced amount of essential amino acids

ex. meat, meat scraps, bone meal, milk etc

vegetable proteins: <47% protein

ex. soybean meal, peanut oil meal etc

concentrates → energy feeds (< 20% protein)

grains & by products

ex. corn, oats, barley, wheat, dried beet pulp

feed analysis

chemical, drying, burning or wet chemistry procedures that determine the major chemical components of feed

• moisture

• crude protein = true protein & nonprotein nitrogen

  • protein in feed is about 16% nitrogen

  • analyze feed for % nitrogen then multiply by 6.25 to get % crude protein

  ex. 100 grams of feed containing 3% nitrogen

  • 3% x 6.25 = 18.75 grams of protein

• net energy (NE): indicator of true energy of a feed

neutral detergent

forage is broken down into cell contents + cellulose, cellulose, lignin

neutral detergent fiber

fairly insoluble materials in cell wall, low neutral detergent fiber is desirable

ex. hemicellulose, cellulose, and lignin

broken down with acid detergent

acid detergent fiber

least digestible part of plants, low acid detergent fiber is desirable

ex. cellulose and lignin

broken down with 72% sulfuric acid into cellulose and lignin