Cereals Flashcards
Types
Corn/maize Wheat Barley Oats Rye Millet
Character of a good ration
- maximalise production and performance
- not harmful to health and quality of animal products
- proper proportions of concentrates and roughages for type and age of animal
Summary
- C. protein: 10-15%, Lys,Met + Cys low, medium BV
- C. fiber: low (2-3%, exc. oat),
- EE: low (2-3%, exc. oat,corn),
- NFE: high (70-80%),
- DE: high (12-15 MJ/kg),
- Ca: low (0,3-1,0 g/kg),
- P: (3-4 g/kg),
carbs from plant perspective
(1) simple sugars active in plant intermediary metabolism;
(2) storage compounds such as sucrose, starch, and fructans;
(3) structural carbohydrates such as pectin, cellulose, and hemicellulose
Carbs as chemicals
- Monosaccharides: simple carbohydrates, cannot be degraded to more simple sugars: glucose, fructose
- Disaccharides and oligosaccharides: two or more monosaccharide molecules: lactose, sucrose, maltose, cellobiose
- Polysaccharides: giant molecules with complex structure, large number of monosaccharide molecules: starch, a glycogen and cellulose
Starch
Amylose and amylopectin
Ratio: pl. wheat flour 30% amylose vs. corn 70% amylose
-ratio influence digestibility
-more glucose can be derived from amylopectin
Classification of carbs
- Hydrolysable CHO /NSC: non structural carbohydrate: simple sugars(quick absorption) and starch(amylase)
- Fermentable CHO/ fibers: cellulose, hemicellulose and pectin(microbial fermentation in the caecum and large colon VFA)
A hydrolysable group (CHO-H) measured by direct analysis: includes simple sugars, sucrose, and some starches that are readily digested in the small intestine and produce fluctuations in blood glucose after feeding
A rapidly fermentable group (CHO-FR) that yields primarily lactate and propionate. This group includes: starches that escape digestion in the small intestine as well as galectins, fructans, gums, mucilage, and pectin
A slowly fermentable group (CHO-FS) that yields mostly acetate and butyrate. This group includes the compounds captured in neutral detergent fibre(NDF) such as cellulose,hemicellulose, and lignocellulose
Fiber types
- Soluble fibers
- pl. pectins, some hemicellulose (eg beta-glucan), inulin (fructane group)
- gelatinizing (gel forming) –slow down/preventionof the absorption of some nutrients
- some are fermented in the large colon –VFA production
- Non soluble fibers
- cellulose, hemicellulose and lignin
- water retention
Average value of some nutrients
*Crude fiber - low (2-3%, oat, barley); - best: oat
*NSP (non-starch polysaccharides): B-glucans, pentosanes, pectin
- Monogastricanimals can’t digest => ferment,
- Large viscosity:
Positive effect
Beta-glucans: immunostimulant (oat and barely) Increase small intestinal starch digestion and stabilize blood glucose
inulin= prebiotics
Negative effect
antinutritive effect (impaction, obstruction)
decrease digestibility
*Crude Protein (CP) - 10-15% (low or medium level), - 80-95% of CP is True Protein, - good digestibility, - poor in Lys (3-4 g/kg), and Met + Cys (3-5 g/kg),
- Biological Value (BV): medium, BV = retained N/absorbed N.
*Ether Extract (EE) - low (2-3%) Oat and Corn - type of fat (animal products) - omega ratios - fat soluble vitamins
*Minerals Ca: very low (0.3-1.0 g/ kg), P: reasonably high (3-4 g/kg) - 50% of the P is in form of Phytate P =>worse bioavailability;
*Vitamins - vitamin B group (but B12), vitamin E.
Biological Value (BV)
- Enviromental
- Clinical dietetics: Renal Hepatic
- Performance: energy loss, fluid loss
carcass fat from pigs fed on Corn vs. Barley
slightly softer and yellower softer consistency reflects the content and quality of fat in corn: cornfat substantially higher than that in barley the fat that is present in corn tends to be highly unsaturated and soft (oily) the colouris due tothe presence of a pigment (cryptoxanthin)
In some parts of the world,this colouris considered undesirable.
Phytic acid
- principal storage form of phosphorus in many plant tissues, especially bran and seeds
- strong binding affinity to phosphorous and minerals such as calcium, magnesium, iron, copper, and zinc- results in precipitation, making the minerals unavailable for absorption in the intestines
- non-ruminant animals: lack the digestive enzyme phytase, so phosphorus and inositol in phytate form is not bioavailable
- ruminants: digest phytate because of the phytase produced by rumen microorganisms
- source: hulls of nuts, seeds and grains
Horse
-Corn max. 30%
-Hydrolysable carbohydrates (CHO-H) important component of equine diets, particularly for the performance horse, where blood glucose serves as a major substrate for muscle glycogen synthesis
-Too much blood glucose, however, may contribute to or aggravate certain problems in horses:
▪ such as equine Cushing’s disease (ECD), equine metabolic syndrome (EMS),
▪ developmental orthopedic diseases (DOD),
▪ recurrent equine rhabdomyolysis, (RER), and polysaccharide storage myopathy (PSSM).
▪ adversely affect behavior in certain individuals.
-obesity
-dysbiosis , thyphlocolitis: excessive intake of grain(easily fermentable carbohydrates) lactate↑, pH ↓; endotoxins
-laminitis (nutritional):
▪ Carbohydrate overload
▪ Pasture associated laminitis (fructans)
-Endotoxaemia: inflammatory condition of the tissues (laminae) that bond the hoof wall to the pedal (coffin) bone in the horse’s hoof
-Biogen amines + hyperglycemia/hyperinsulinaemia: increases in capillary pressure, ischemia, increased vascular permeability leads to oedema within the hoof, compression of small vessels and nerves
Ruminants
-Acute rumen acidosis (2–6 hr)
▪ intake of a high level of rapidly digestible carbohydrate, lactic acid ↑,pH ↓→metabolic acidosis
▪ laminitis
▪ liver abscess
-Chronic rumen acidosis (subclinical)
▪ feeding excessive amounts of rapidly fermentable carbohydrates in conjunction with inadequate fiber
▪ reduced feed intake
