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417 Cards in this Set
- Front
- Back
Fermentation in the horse occur |
In the cecum and colon after the small intestine |
|
Fermentation in cattle occur |
In the rumen prior to the small intestine |
|
Nutrition has profound influences on the health of the animal in |
Laminitis (Horse); Obecity (Dog); Renal failure (Cat); Milk fever (Dairy cattle) |
|
Where cost is not an issue people will pay up for |
Expensive feed that prevents certain diseases (tying up in horses);
Amino acids and vitamin supplements (better temperment horses);
Less odorous faeces, more palatable food, food that looks nicer |
|
Nutrition closely related to health and wholley controlled by the owner |
Preventative medicine - avoid illnesses through proper nutrition |
|
All important nutrients bar water will be found in |
Dry matter |
|
Inorganic nutrients |
Copper, cobalt etc. major components of many enzymes of the body |
|
Organic nutrients |
Extremely important to the maintenance of animal |
|
Water essential for |
Life - prevention of dehydration and fight against diarrhea |
|
Variable water content in body mass |
Newborn animal up to 90%; fat animal 50% |
|
Two major functions of water |
Metabolism (all biochemical rxns; medium for transport in digesta, blood, urine, sweat);
Temperature regulation (sweating, panting) |
|
Metabolic water |
Formed during metabolism by oxidation of hydrogen containing organic nutrients;
Important source for hibernating animals |
|
Sources of water |
From metabolism, from feed, from drinking water |
|
Water content in air dry concentrates |
10-15% water |
|
Water content in succulent feeds |
70%+ water |
|
Water content in root crops |
80%+ water |
|
Water content in hay/straw |
10-15% water |
|
Water content in silage |
5-84% water |
|
Water adds |
No calories but does add palatability |
|
Factors affecting water requirement |
Production (growth, eggs, milk);
Diet and dry matter intake (food, salt);
Species and size;
Athletic performance; Environment (temperature, rainfall, humidity);
Health (haemorrhage, vomiting, diarrhea) |
|
Difference in amount of food required between wet and dry |
A greater weight of the wet food will need to be fed in order to get the same amount of nutrients as in dry food (nutrients in wet food more dilute) |
|
Equalize the amount of nutrients in a feed by |
Taking it as a measure of the dry matter content (content in a feed after all moisture is removed) |
|
70% of the dry matter of plants is made up by |
Carbohydrates |
|
Carbohydrates are what % of an animals body |
1% |
|
Sugars are |
carbohydrates contained less than 10 monosaccharides |
|
Polysaccharides |
3 or greater strand of monosaccharides - include starch, cellulose, hemicellulose etc. |
|
Over time grass becomes more stemy meaning it increases in which type of carbohydrate |
Structural carbohydrates (ex. cellulose) |
|
Non-structural carbohydrate |
Starch |
|
Starch is made up of |
amylose and amylopectin |
|
Starch is readily broken down by |
Pancreatic and salivary amylase; mammalian enzymes; almost completely digestible is exposed |
|
Structure of amylose |
Linked at Carbon 1 and 4 or 1 and 6 by alpha linkages |
|
Structure of cellulose |
Linked at carbon 1 and 4 by beta linkages |
|
Cellulose is a major component of |
Plant cell walls and cannot be digested by mammalian enzymes;
Microflora of rumen in ruminants can break it down (produce cellulase) |
|
Cellulose digestibility is decreased by |
Lignin |
|
Hemicellulose differs from cellulose only in |
How the individual molecules are linked; complex group of cell wall polysaccharides that cannot be digested by mammalian enzymes |
|
Lignin is |
Not strictly a carbohydrate |
|
Lignin acts as |
Intercellular cement and is associated with plant cellulose and hemicellulose;
Very resistant to enzyme degredation;
Amount increases with age of plant; |
|
Lignin affects feed by |
Reducing digestibility; Cellulose becomes significantly less digestible in the presence of lignin |
|
Lipids / Fats / Oils |
Organic compounds insoluble in water but soluble in organic solvents |
|
Fats refer to |
Solid lipids |
|
Oils refer to |
Liquid lipids |
|
Major role of lipids is |
Energy storage |
|
Brown fat has a role in |
Temperature regulation |
|
Amount of energy in fat compared to carbohydrate |
Contains twice as much energy |
|
Lipids a source of essential fatty acids which are |
Fatty acids that cannot be synthesized in mammals |
|
Essential fatty acids are important for |
Heart disease;
Immunity;
Inflammation;
Joint disease;
Skin health;
Reproduction |
|
Lipids are carriers for |
Fat-soluble vitamins (A, D, E, and K) |
|
Lipids are a constituent of |
Cell membranes |
|
Glycerol + Fatty acids = |
Triglyceride |
|
The most common way for lipids to be added to the diets is |
As triglycerides |
|
Saturated fatty acids have no |
Double bonds in the C,H, and O chains (maximum hydrogens);
Shorter chains are usually solid at room temperature (Fats) |
|
Unsaturated long chain fatty acids are usually |
Liquid at room temperature (Oil) |
|
The number and location of double bond in lipids dictates |
What purpose the lipid has or if it is just used for energy |
|
Fatty acid name meanings |
First number - How many carbons are present;
Second number - Number of double bonds;
N - position relative to the last carbon atom |
|
Linoleic acid and linolenic acid |
Cannot be synthesized so much be fed (dietary essentials) |
|
Arachodonic acid |
Synthesized at a slow rate de-novo, so required if C18:2 lipid is not present |
|
Essential fatty acid requirements related to |
Prostaglandin;
Hormone like substances;
Regulate blood clotting, pressure;
Smooth muscle contractions;
Reproduction;
Immune responce |
|
EPA eicosapentaenoic acid
DHA docosohexaenoic acid
Important in |
Cardiovascular function;
Brain function;
Rheumatoid arthritis |
|
Signs of essential fatty acid deficiency in non-ruminants |
Reduced growth rate;
Dy scaly skin;
Lack of sheen on hair;
Infertility;
Poor wound healing;
Irritating skin conditions |
|
Oxidation of fats is known as |
Rancidity |
|
Unsaturated fatty acids oxidised at double bond to produce |
Hyperoxides
Shorter chain fatty acids free radicals and taints and off-flavour compounds (aldehydes and ketones);
Catalysed by U.V. light, Cu, and Fe |
|
Antioxidants protect from |
Oxidation of fatty acids; Se, Vitamin E, beta-carotene; Synthetic versions added to feedstuffs to protect from oxidation |
|
Naturally occurring antioxidants |
Tocopherols (Vit E) |
|
Synthetic antioxidants |
Butylated hydroxy toluene (BHT) |
|
Hydrogenation |
Conversion of unsaturated fatty acids to saturated fatty acids;
Hardens fat and improves keeping quality; much fat hydrogenated in the rumen |
|
Benefits of dietary fats |
Concentrated energy source;
Flavour / Palatability;
Satiety effect;
Fat soluble vitamin carrier;
Source of essential fatty acids;
Decreased feed dust;
Pelleting lubricant |
|
Main contributer of obesity is |
A high fat diet |
|
Clinical abnormalities associated with lipid metabolism |
Artherosclerosis heart disease and artherosclerotic plaque from cholesterol;
Low density lipoprotein - cholesterol and coronary heart disease;
High circulating triglycerides and coronary heart disease;
Fatty liver - increased liver lipogenesis - high fat or cholesterol diet |
|
Proteins are |
Complex organic compounds made up of C, H, O, N, and S; Have 16-18% nitrogen content;
Singular unit is an amino acid |
|
Chain of amino acids are called |
Peptides (dipeptides, tripeptides, polypeptides) |
|
Proteins found in |
All living cells;
Collagen, Keratins, elastin |
|
Essential amino acids |
Protein precursors which the animal is incapable of synthesizing |
|
Rumen micro-organisms can synthesize both |
Essential and non-essential amino acids allowing for very different dietary requirements from monogastrics |
|
Pigs, dogs, and rats require 10 amino acids |
Tryptophan, Threonine, Histidine, Arginine, Leucine, Lysine, Isoleucine, Methionine, Valine, Phenylalenine |
|
Cats and taurine |
Normally synthesized from methionine and cysteine but cannot be synthesized at sufficient rates in the cat and must be supplied in the diet |
|
Chickens essential amino acid |
have 10 plus glycine |
|
First limiting amino acids |
One or two essential amino acids limiting growth and production |
|
First limiting amino acids in poultry |
Methionine |
|
First limiting amino acids in pigs |
Lysine or tryptophan |
|
First limiting amino acids in equine |
Lysine |
|
First limiting amino acids in dairy |
Lysine and methionine |
|
Protein needed in ruminants as a |
Substrates for microbes which produce both essential and non-essential amino acids |
|
Amino acids used in ruminants come from either |
Microbial produced proteins and rumen undegradable proteins |
|
Effects of low protein |
Decreased intake and feed utilization;
Decreased growth rates;
Decreased PCV, red cell count;
Decreased wound healing;
Poor colostrum quality;
Catabolism of body proteins;
Decreased immune response |
|
Proteins are used as an energy source when |
Energy is limiting; Happens by deamination mainly in the liver producing urea;
Excretion of urea has an energy cost making this a very ineficient way to provide energy;
Can be used for weight loss but puts additional strain on kidneys and liver |
|
Proteins and amino acids as building blocks for |
Biological substrates such as enzymes, elastin, skeletal muscle |
|
Animal Feedstuffs are made up of |
Moisture; Carbohydrate; Protein; Lipids (Oil or Fat); Ash; Also vitamins, nucleic acids etc |
|
Most common system of feed analysis |
The proximate analysis system; the legal basis for declared analysis |
|
The proximate analysis system is made up of |
Moisture/Dry Matter (DM%);
Crude protein (CP);
Crude Fibre (CF);
Ether extract (EE) (Lipids);
Ash;
Nitrogen free extracts (NFE) (Carbohydrates) |
|
Dry Matter (DM) |
The percent of the feed that is not water/moisture;
Moisture and dry matter sum to 100% |
|
In order to compare nutrient concentration the feed must be at similar |
Dry matter %;
So nutrients are at comparative concentrations |
|
Nutrient content on labels listed on an |
As fed basis;
Listed in a % of the full feed including moisture (aka in the state it is fed) |
|
DM% = |
Dry sample weight / original sample weight |
|
DM is determine by |
Drying out the feed at 105 degrees for 16 hours until weight change stops |
|
Crude Protein (CP) |
Most common method for analysis of total protein concentration in farm and companion animal feeds |
|
Crude protein determination based on |
Nitrogen concentration - assumes protein contains 16% Nitrogen |
|
CP% = |
N% x 6.25 |
|
Kjeldahl Method |
All free nitrogen converted to ammonia;
CP concentration based on N concentration which is based on ammonia concentration;
Assumption that all protein contains 16% N
Assumption that all N is from protein
Very crude estimate |
|
Ether Extract (EE) / Crude Fat % |
Crude estimate of the total lipid concentration in feed |
|
Ether extract determined by what process |
Feed is rinsed for a pre=determined period of time with petrolium ether;
Petrolium ether is evaporated off;
Left with feed minus the oil (as well as organic acids, sterols, and lipid soluble vitamins) |
|
Ether Extract (EE) / Crude Fat % consists of |
The lipid content of the feed as well as organic acids, pigments, sterols, and lipid soluble vitamins;
Crude measurement of lipid |
|
Crude Fibre (CF) |
An approximation of concentration of plant cell wall in feedstuffs (cellulose, hemicellulose, lignin) |
|
Crude fiber is determined by |
Successively boiling sample in acid then alkali and weighing the residue;
What is removed does not consist of all of the cell wall content making this one of the most inaccurate measurements |
|
High levels of crude fiber likely indicate |
Low digestibility of the feedstuff; Indigestible by mammalian enzymes |
|
Ash |
An estimate of total inorganic matter or mineral concentration in feeds;
Supplies no energy value;
Organic Matter % (OM) + Ash % = 100% |
|
Essential mineral elements in ash |
Major: Ca, P, Mg, S, Na, K, Cl
Trace: Cu, Co, I, Zn
Non-essential elements: Al, Pb, etc.. |
|
To determine ash content of feed |
Place feed in furnace for 4 hrs at 550-600 degrees Celcius |
|
OM is important because |
it is the energy yielding component of feed |
|
Nitrogen Free Extractives (NFE) |
Component of feed digestible by mammalian enzymes;
Whats left after all other fractions are removed;
Digestible carbohydrates (starches, sugars, pectins, organic acids, pigments);
Also contains some cellulose, hemicellulose, and lignin |
|
NFE% = |
100 - (Moisture% + Ash% + CP% + CF% + EE%) |
|
NFE is the easy was to determine |
Utilizable feed (Estimate the energy value of diets) |
|
Van Soest Detergent System |
Determine plant cell walls and plant cell contents (Fiber analysis);
Based on the use of detergents and acids |
|
Neutral detergent fiber (NDF) consists of |
Cellulose, Hemicellulose, and Lignin;
Measure of total cell wall carbs (structural carbs or fiber);
Contains small concentrations of fiber bound protains, lignified nitrogen, minerals, cutin |
|
Acid detergent fiber (ADF) consists of |
Cellulose and Lignin;
Less digestible than NDF;
Good relationship with digestibility |
|
Acid detergent lignin (ADL) consists of |
Lignin |
|
Structural carbohydrates |
Plant cell wall;
Digest slowly and not completely;
Contains Cellulose, Hemicellulose, and Lignin |
|
Non- structural carbohydrates |
Plant cell contents;
Digest quickly and completely;
Contains starch, sugars, and pectin |
|
Most accurate measure of 'fiber' |
Neutral detergen fiber (NDF); |
|
Neutral detergent fiber (NDF) indicates |
Digestibility, filling effect, rate of digestion |
|
Neutral detergent fiber (NDF) determined by |
Boiling feed in sodium lauryl sulphate and EDTA (same as detergent);
The residue is NDF |
|
Acid detergent fiber (ADF) determined by |
Boiling feed in sulphuric acid |
|
Acid detergent lignin (ADL) determined by |
Very strong acid used to leave only lignin as the residue;
Most indigestible part of the cell wall;
Presence reduces the digestibility of cell wall |
|
Amino acids, fatty acids, vitamin concentrations are determined using |
Chromatography;
Detection devices generate electrical signal based on number of carbon atoms that exit column at different times;
Separation based on physical properties |
|
Chromotography graph |
Peaks at different times indicating content with the amount of mV indicating the amount of that substance present |
|
Minerals and Trace Elements |
Atomic absorption spectroscopy;
Technique available to determine the actual proportion of components in ash |
|
Atomic absorption spectroscopy |
Acid solution of sample heated in a flame;
Different elements release radiation at different specific wavelengths;
Vaporised atoms absorb light;
Amount of light absorbed proportional to concentration of element |
|
Calorimetry |
Energy measurement (gross energy) |
|
Productive capacity of all nutrients in feed organic matter |
Growth;
Maintain body temperature;
Athletic performance;
Immune response |
|
Calorimetry works by |
Heating known weight of feed and measuring temperature rise of water near feed;
Temperature rise in water jacket = energy released at combustion
Measured in calories or joules;
Technique is adiabatic = no heat added no heat lost |
|
Near infrared reflectance spectrosopy |
Powerful new feed analysis tool;
Used to predict CP, WSC, ADF, NDF but not ash or minerals;
Light shone through feedstuffs, different components cause different light scatterings (reflectance or absorption);
Calibrations required before each measurements |
|
Large variable component of feedstuffs lost to |
The animal |
|
Largest most variable component of feedstuffs is lost in |
The animals faeces |
|
Digestibility measures |
The proportion of feed constituent that is not excreted in faeces |
|
Digestibility types |
Dry matter digestibility (DMD); Organic matter digestibility (OMD); CPD; NDFD; GED |
|
Calculate digestibility |
Faecal DM / DM Intake = % Indigestibility;
Digestibility = 100 - % Indigestbility |
|
Calculate organic matter digestibility |
(Faecal DM - Faecal ash) / (Dry matter intake - Ash content) = OM Indigestibility;
OMD = 100 - OM Indigestibility
Higher % of ash in the faeces because becomes more concentrated (OM gets digested ash does not) |
|
Digestibility values determined by |
Measuring amount fed and collecting faeces for a number of days |
|
Average quality dog food |
Low fiber digestibility (likely higher in non-digestible substances such as lignin) |
|
Good quality dog food |
High fiber digestibility |
|
Digestible organic matter in the dry matter (DOMD) |
A measure of the concentration if digestible energy yielding nutrients in the feed DM |
|
Digestible energy concentration (DE) |
A more accurate estimate of concentration of digestibility energy yielding nutrients in feeds |
|
Apparent digestibility |
Determined through faecal collection and considers the entire amount as indigestible feed;
Faeces contains more than just undigested foods;
Micro organism; endogenous secretions; enzymes |
|
True digestibility |
Considers only the undigested feed as the indigestible amount (will be higher than the apparent digestibility because the amount indigestible is less) |
|
Factors effecting digestibility |
Feed composition:
Fiber or cell wall - digestibility very variable
Cell wall content - digestibility higher than fiber
Protein animal / vegetable - true digestibility usually 85 - 100% |
|
Concentrates usually have |
Higher digestibility than forages |
|
Fiber has a very limited digestibility in the |
dog and cat |
|
Chemical treatment of feeds to breakdown cell wall linkages |
Ammonia treatment of forages;
Sodium Hydroxide treatment of grains;
Urea treatment of grains / whole crop cereals;
Acid treatment of grains |
|
Physical treatment of feeds |
Rolling;
Grinding - reduces forage digestibility;
Crimping - inexact, not as effective as rolling;
Flake - moistened then rolled;
(Horses and sheep no benefit, cattle and pigs benefit total tract DMD) |
|
Heat treatment of feeds |
Micronization, Extrusion, Roasting;
Advantages with some cereals for ruminants;
May denature proteins in dog and cat foods;
Causes gelatinization of starch which makes it more digestible for more animal species |
|
Combination of heat treament and physical treatment |
Steam flaking |
|
Soybean flour in dog diets more digestible than |
Soybean grits |
|
Blended rice in dog diet more digestible than |
Whole rice |
|
Finer material tends to be more digestible because |
Greater surface area exposed to enzymes involved in digestion |
|
High temperature drying can reduce the digestibility of |
Meat and bone meal and poultry meal in dog and cat diets |
|
Maillard products |
Chemical alterations created by damaged proteins causing less digestibility |
|
High temperature drying in farm animal protein sources can |
Decrease digestibility (distillers dried grains and grass meal) |
|
Cattle digestion vs sheep digestion |
Cattle better digest long fiber while sheep better digest concentrates |
|
Factors affecting digestibility |
Species; Ruminant vs Non-ruminant; Cattle vs Sheep; Feed DE concentration |
|
As food passage rate increases digestibility |
Declines (Up to 12%);
Caused by feed allergies, more food, stress |
|
Compartmental digestion in the horse |
Important pre-cecal digestion of starch - too much makes to to the cecum could cause digestive upset (Colic);
Micronized corn is best; oat next best but cause freshness; If remove oats replace with cooked cereals to maintain pre-cecal digestion of starch |
|
Compartmental digestion in ruminants |
Protein digestion in the rumen = rumen degradability (Requires fistulated animals);
Needed to determine protein supply to the rumen micro organisms |
|
Rumen degradability estimates |
Solubility of feed protein;
Rate of protein disappearance for insoluble fraction;
Rumen retention time |
|
Best predictor of digestibility (for welfare of animal and total tract digestibility) |
Near infrared spectroscopy (NIRS) |
|
Tillery and Terry |
In-vitro digestibility assay of rumen fluid |
|
EFOS Method |
In-vitro digestibility assay of pig gastric, pancreatic, and microbial enzymes |
|
Winter milk production |
50% of the diet |
|
Winter finishing of beef cattle |
Up to 90% of the diet |
|
Straights |
Concentrate feed ingredients used as a sole identifiable dietary component (Eg. barley, beet pulp, oats) |
|
Blends |
A mix of straights no mineral added minimal processing |
|
Course mixes / muesli / crunches |
Mixes of concentrate feed ingredients where ingredients mixed with minimal processing individual ingredients often identifiable contains mineral and vitamin supplements formulated for specific species |
|
Compounds |
Mixes of concentrate feed ingredients blended together following mechanical and thermal processing contain mineral and vitamin supplements, flavours and other additives formulated for specific species;
Pellets, nuts, cubes, pencils, meals, crumbs |
|
Using supplements designed for one species for another can lead to |
Toxicity (high selenium salt for cows can kill a horse) |
|
What is quality? |
Digestibility of energy (available calories);
Supply of digestible protein;
Type of energy / differences between species;
Quality of protein / lysine content important;
Palatability;
Potential for toxins / plant or fungal metabolites that cause morbidity or mortality (Not as dangerous in ruminants) |
|
Feed ingredient classes |
Cereal grains;
Cereal by-products;
Oilseed by-products;
Sugar by-products;
Fruit by-products |
|
Cereal Grains |
Barley, wheat, maize, oats, sorghum (not used much) |
|
Cereal by-products |
Maize gluten feed, Maize gluten meal, maize distiller grains, pollard wheat bran, brewers grains |
|
Oilseed by-products |
Soyabean meal, soya hulls, rapeseed meal, sunflower seed meal, palm kernal meal, cotton seed meal |
|
Sugar by-products |
Molassed sugar beet pulp, Unmolassed sugar beet pulp, Cane molasses |
|
Fruit by-products |
Citrus pulp |
|
Barley; Energy supplement; Cereal grain |
One of the most popular cereals used;
Higher fiber lower starch than wheat;
Low pre-cecal digestibility in horses if uncooked;
Low in Ca, Low in Lysine |
|
Wheat; Energy supplement; Cereal grain |
High energy, high starch;
High risk of rumen acidosis;
Low in Ca, Low in lysine |
|
Maize; Energy supplement; Cereal grain |
High starch, low protein cereal grain;
Very high energy, highly digestible, high oil;
Should be heat treated for optimal digestion in many species;
Available as ground or flaked;
Low pre-cecal digestibility in horse;
Low Ca, Low lysine |
|
Oats |
High fiber cereal;
High in unsaturated oils;
Commonly used as straight feed for horses;
Causes excitable behavior in horses;
Also used for straight feed in ruminants and sheep |
|
Maize Gluten Feed; Cereal by-product |
Medium energy, medium protein;
Commonly used in ruminant diets;
Low in lysine;
High in fiber - less useful for other species;
Can be used in grower finisher pig and layer breeder poultry |
|
Pollard / Wheat bran; Cereal by-product |
Medium energy, medium protein;
Outer husks of wheat grains and screenings;
Low Ca;
Used to add fiber / laxative properties;
Often used solely to increase pelleting quality of mix |
|
Maize distillers grains; Cereal by-product |
Medium/high energy, Medium protein;
Very commonly used for ruminant diets;
Limited use for other species;
High fiber level;
Low in lysine |
|
Brewers grains; Cereal by-product |
Low/Medium energy, Medium/high protein;
Ruminant feed;
Usually based on barley grains but may have other types of cereals;
High protein, high fiber, high oil;
Usually fed wet / concentrate, very palatable |
|
Unmolassed sugar beet pulp; By-product of sugar industry |
High fiber by-product of sugar beet;
High energy for ruminants too much fiber for poultry;
Requires soaking if fed straight to horses;
Excellent source of slowly digestible carbs for ruminants |
|
Molased sugar beet pulp; By-product of sugar industry |
Ideal ruminant feed;
Not as high in fiber as unmolassed beet pulp;
Commonly used straight/ as a cool feed in horses;
Extensively used in pig diets except creep diets;
Very palatable;
Low in phosphorous |
|
Cane Molasses |
Low in protein, High sugar feed for all farm animals 65% sugar;
Very palatable - useful for shy feeders;
Aids pelleting; useful in course mixes prevents sorting;
High in potassium and salt, can cause scouring |
|
Citrus pulp; By-product of fruit processing industry |
Low protein, High energy for ruminants, Low energy for pigs;
Antinutritional factor for young pigs and poultry (limonin);
Limited use pigs and poultry;
Palatability is an acquired taste in ruminants;
Common straight feed in dairy cows |
|
Soyabean meal; Oilseed by-product |
High energy, High protein supplement;
Good source of lysine;
Antinutritional factor destroyed on heating;
Used extensively in diets for all species;
Very useful in young monogastric diets;
Very safe high quality high protein feed |
|
Soya Hulls |
Low protein, High fiber feed
Used as a source of digestible fiber in ruminant and pig diets;
Safe feed no antinutritional factor; |
|
Rapeseed meal; Oilseed by-product |
Medium energy, High protein feedstuffs;
Limited use in pig and poultry diets;
Often used to partially replace soyabean meal;
Antinutritional factors - glucosinolates and erucic acid |
|
Sunflower seed meal; Oilseed by-product |
Low energy, High protein feed;
Quality depends on protein and fiber content;
Sunflower hulls high fiber;
Low digestibility;
Good source of methionine |
|
Expelled Pal Kernel Meal; Oilseed by-product |
High fiber feed, Cheap source of energy;
Used as straight feed for ruminants in some areas;
May contain aflotoxins;
High saturated oil content;
Shell pieces may cause lameness if fed straight;
Low in lysine |
|
Cottonseed meal; Oilseed by-products |
High Protein supplement;
Low in lysine;
Limited in pigs and poultry;
May be sold on crude fiber / crude protein low fiber / high protein best;
Anti-nutritional factor called gossypol;
May contain aflotoxins |
|
Grass varieties |
Perennial ryegrass (head out 6 May - 12 June);
Italian ryegrass (head out 22 May - 28 May);
Cutting the grass keeps it from heading out;
Also: Cocksfoot; Meadow fescue; Brome grass; Timothy; Bent Grass; Meadowgrasses; Yorkshire fog; Crested dogstail etc. |
|
Species sown |
Perennial ryegrass- Early (64%), Late (6%);
Italian ryegrass - 19%;
Cocksfoot - 4%;
Timothy - 7% |
|
Old pasture have lower |
Yield and digestibility |
|
Chemical composition of grass differs between young and mature |
Young: CP (30%), CF (20%), Moisture (75-85%) Carbs (3-25%), Cellulose (20-30%), Hemi-cellulose (10-30%);
Mature: CP (3%), CF (40%), Moisture (65%), Carbs (5-30%), Cellulose (20-30%), Hemi-cellulose (10-30%)
Young: Has higher protein, lower fiber, higher moisture, lower carbs |
|
Change in digestibility with increasing maturity |
Decrease in digestibility with maturity |
|
Growth rate of grass through the year |
Lowest in winter, highest in may/june and august |
|
Relative cost of grass and other feeds |
Grazed grass < Silage < Corn gluten < Dairy ration |
|
Aims of grassland management |
Provide supply of high quality herbage over the growing season;
Avoid waste;
Avoid inefficient utilization by animals;
Provide feeding for winter |
|
Cattle graze for |
6 - 11 hours per day |
|
Most common time for cattle grazing is |
Just after dawn and just before dusk |
|
Movement of cattle while grazing |
Slow in uniform crop; Fast in variable crop |
|
Factors affecting intake herbage |
Animal Factors: Metabolic weight, production, stage of lactation;
Sward Factors: Herbage quantity, herbage quality;
Effort of grazing: Difficult conditions |
|
Application of slurry |
Allow 5 weeks from application to grazing;
Contains N, P, and K |
|
Full return of faeces and urine increases |
Yield by 20-40% |
|
Continuous stocking |
Stock have access to one area for entire grazing season |
|
Intensive continuous stocking |
Reduce number as grass supply drops |
|
Rotational Grazing (paddock grazing) |
Divide into number of similar sized paddock;
Stock moved in sequence around |
|
Strip grazing |
Move electric fence daily or every 12 hours;
Rotation cycle 21-30 days |
|
Leader-follower rotational grazing |
Two groups, one follows other;
Better use of grass, less waste;
Lambs ahead of ewes, calves ahead of older cattle (less likely to get parasites) |
|
Integrated grazing and conservation |
Subdivide pasture into 2 sections in ratio 60:40 (for beef cattle);
Early season graze 40%, conserve 60%;
Mid season graze 60%, conserve 40%;
End season graze 100% |
|
Alternate cutting and grazing |
Graze part, cut early season in mid season vice-versa;
Improves grass quality;
Can have shortage of grass for few weeks |
|
Zero grazing |
Harvest all grass and feed as silage (good utilisation but expensive) |
|
The greater the sward height |
The greater the dry matter yield |
|
Animal problems at pasture |
Parasites; Mineral deficiency / Toxicity; Bloat |
|
Bloat |
Common with diets high in legumes (Lucerne, Clover);
Problem with lush grass;
Control: Anti-foam in water, Provide some fibrous feed, Feed small quantities of pasture high clover |
|
Haymaking |
Reduce moisture content of forage to 20% or less;
Suppress fungal growth, thermophilic bacteria, molds (farmers lung);
Weather most important - drying conditions low humidity;
Mature herbage dries easier and quicker |
|
Effect of rain on hay quality |
Increases moisture content - prolongs enzyme actions, increases tossing required and leaching;
Encourages mold growth |
|
Nutrient losses during haymaking |
Plant enzymes; Oxidation; Mechanical damage; Leaching |
|
Silage |
Produced by controlled fermentation of crop at high moisture content;
Produces organic acids from bacterial action on sugars; |
|
Quantity of acids produced in silage proportional to |
The amount of sugar; Type of bacteria; Type of crop; Moisture content |
|
Two fermentation types |
Aerobic fermentation;
Anaerobic fermentation |
|
Aerobic Fermentation |
Air trapped in crop when ensiled;
Loss of carbohydrate by respiration;
Increased temperature could lead to protein denaturation |
|
Anaerobic Fermentation |
In absence of air anaerobic microbes (Lactobacilli, streptococci, pediococci) produce acid and preserve the crop;
Type and quantity of acid critical: Lactic acid desirable;
Clostridia produce butyric acid which leads to protein breakdown and poor fermentation |
|
Relationship between acid type and silage quality |
When lactic acid is high, Butyric acid ammonia nitrogen and pH is low (and vice versa) |
|
Moisture content of silage |
Low DM herbage (<18%) - Needs high level of acidity to check clostridial growth;
Dryer herbage (25-28% DM) - pH 4.4 adequate;
High DM herbage (30+%) - Initial fermentation to pH 4.8 adequate; |
|
Soluble carbohydrate content of silage depends on |
Grass species (ryegrass increases it);
Weather (poor decreases it);
Nitrogen fertilizer (decreases it);
Time of N application (< 1 month decreases) |
|
Require sugar levels higher than |
3% in fresh grass for preservation of silage |
|
Wilting to improve preservation |
Decrease effluent;
Increase dry matter;
26% DM normally results in good preservation |
|
Additves to improve preservation |
Used in difficult crops and difficult conditions;
May protect proteins and improve animal performance |
|
Value of silage as a feed |
Quality of silage: Energy content, protein content;
Amount animal eats: Taste, smell, etc. |
|
On-Farm assessment of silage quality |
Variable layers;
DM Content - how much water can be squeezed out;
ME Value - Leafiness, courseness of stem
Type of fermentation - well fermented (yellow green, fruity smell)
pH - check with lithmus paper |
|
Laboratory assessment of silage quality |
ME Value;
Digestible crude protein;
Ammonia content;
pH |
|
Importance of silage cutting date |
Late cutting means loss of 10 and 20 days regrowth respectively |
|
Silage making |
Exclusion of air; Final sealing; Effluent (wilted); |
|
Silage and Health |
Reasonably clean record; All visibly spoilt silage should be thrown away not given to animals; |
|
Dangers of Silage |
Moulds / black / contamination / excess fermentation / stemminess |
|
Moulds in Silage |
Aspergillus sp. linked to abortion in cattle and sheep;
Linked to COPD and lung problems in horses from mouldy hay |
|
Botulism |
Contamination by dead carcasses, soil, manure;
Clostridium botulinum may multiply in silage |
|
High ammonia levels in silage |
Associated with lameness and scour in dairy cows;
Inverse relationship between dry matter content of silage and lameness |
|
Wet, Low pH Silages |
High sugar, wet grass ensiled with an effective innoculant;
Highly acidic - low intakes, acidosis (especially when combines with high concentrate intake) |
|
Listeriosis |
Disease in cattle and sheep sometimes linked to feeding incompletely sealed big bale silage;
Listeria monocytogenes soil born, associated with aerobic seterioration |
|
Feed contains what kind of energy |
Chemical energy |
|
Many biological processes need energy |
Muscular contraction, digestion, absorption, circulation, excretion, respiration, maintenance of body temperature |
|
Energy containing products produced within body |
Milk fat and protein, adipose tissue and skeletal muscle GI tract cells, enzymes, hormones, white blood cells |
|
Animals need nutrients for |
Activity, Maintenance of body temperature, tissue production, biological process |
|
Compare energy required for general processes to |
Chemical energy supplied from feed |
|
Energy losses in animal nutrition |
Feed Gross Energy (GE) --> Digestibility (DE) --> Metabolisable Energy (ME) --> Net Energy (NE) |
|
Digestible Energy (DE) = |
GE - Faecal Energy |
|
Metabolisable Energy (ME) = |
DE - Methane and Urinary Energy |
|
Net Energy (NE) = |
ME - Heat Increment |
|
Energy Requirements |
Maintenance, Tissue Production, Activity |
|
Net energy used for |
Maintenance; Production of body growth and foetal growth |
|
The heat increment is largest and most important for |
Ruminants - also very variable depending on the feed |
|
Best estimate of available energy in feed is |
NE for calculated for cattle and sheep |
|
Feed NE values and animal NE requirements expressed |
Relative to the NE content of barley |
|
Feeds have two NE values |
UFL / UFV depending on what processes energy is used for (sometimes written as UFLI and UFVI) |
|
UFL |
For maintenance and lactation and slow growers |
|
UFV |
Rapidly growing animals |
|
1.00 UFL = |
The NE content of 1kg of air dry standard barley for milk production = 1700 kcal;
Animal requirements: maintenance and lactation |
|
Animals that use UFL |
Dairy cows/ewes in lactation, pregnancy or dry periods;
Dairy heifers or ewe lambs;
Wintering or slowly growing animals;
Breeding male cattle;
Dairy goats |
|
1.00 UFV = |
The NE content of 1kg of air dry standard barley for meat production at an animal production level (APL) of 1.5;
APL = (NEm = NEg) / NEm;
Animal requirement for maintenance and weight gain at a given maintenance : gain ratio |
|
Animals that use UFV |
Rapidly growing steers, bulls, beef heifers;
Fattening steers, bulls, beef heifers, lambs;
Cattle with daily gains > 1kg/d |
|
Daily UFL for maintenance special values |
Increase 10% for loose housed cows;
Increased by 20% for cows at pasture;
Reduced by 10% for dry beef cows |
|
Daily Dairy Cow UFL for maintenance = |
1.4 + 0.6 LWT/100 |
|
Daily Sheep UFL for maintenance = |
0.033 x LWT^0.75;
Increased by 10% out-wintered ewes |
|
The higher you go with the fat content |
The more UFL you need per kg of milk |
|
Assumptions made in diet formulation |
That UFL values of the diet are additive;
Feeding concentrates reduces forage digestibility;
Diet digestibility reduced as feeding levels increase |
|
Feed conecntrates with forage decreases forage digestibility because |
The acidity of the rumen increases causes death of some of the bacteria |
|
Changes in body weight dairy cow;
1kg of body weight loss |
Supplies 3.5 UFL |
|
Changes in body weight dairy cow;
1kg of body weight gain |
Requires 4.5 UFL |
|
Changes in body weight dairy cow;
Loss of one unit body condition score |
Supplies 150 UFL |
|
Changes in body weight dairy cow;
Gain of one unit of body condition score |
Requires 200 UFL |
|
Protein synthesis in tissues such as |
Liver or muscle cell etc. |
|
Protein essential for life |
Cell turnover, blood cells, enzymes, hormones |
|
Growth and production by proteins |
Skeletal muscle, foetal development, milk production |
|
In large intestine bacteria can |
Digest and modify protein but is after site of absorption |
|
In Monogastrics:
Protein sources differ in their |
Digestibility and the proportion of absorbed amino acids used in body tissues |
|
The quality of protein sources may be assessed by |
Biological value = (Food nitrogen - [faecal nitrogen + urinary nitrogen]) / (Food Nitrogen - Faecal Nitrogen) |
|
Biological value measures |
The proportion of digested N that is used for protein synthesis in body tissue |
|
Biological value is high when |
The amino acid composition of the tissue being synthesized is similar to that of the feed |
|
Net Protein Utilisation (NPU) = |
Combines digestibility with biological value
Biological Value x Protein Digestibility |
|
The most important characteristics of protein quality for monogastric animals are |
Digestibility and amino acid profile |
|
Animal based protein sources have |
High biological value;
But have to move away from using some animal proteins (Mad cow scare) |
|
Ideal amino acid profile |
Ideal amino acid profile |
|
Essential amino acid index |
The sum of the proportion of each essential amino acid for a reference tissue (egg often used as a standard) that is provided by each essential amino acid in the feed |
|
Diets formulated on the basis of CP and |
The essential amino acids likely to be limiting in typical diets |
|
CP and essential amino acids for pigs |
Lysine, Methionine + Cystine and Threonine |
|
CP and essential amino acids for horses |
Lysine |
|
CP and essential amino acids for cats and dogs and poultry |
Many essential amino acids |
|
Younger animals, lactating animals, pregnant animal have |
Higher protein requirements |
|
Older animals have |
Lower protein requirements |
|
Ammonia in the rumen produced by |
Protein hydrolysis, peptide degradation, amino acid deamination |
|
Fermentation in rumen;
Bacteria, Protozoa Numbers |
1 billion to 10 billion bacteria per ml of rumen fluid;
100 thousand to 10 million protozoa per ml of rumen fluid |
|
Main rumen bacteria |
Bacteroides Amophillus; Bacteroides Ruminacola; Butyrivibrio Fibrosolvens;
Proteolytics 30% of biomass in rumen |
|
Bacteria and protozoa use protein breakdown products to |
Fuel their nitrogen requirements for multiplication in the rumen |
|
Some bacteria use ammonia |
Other only need amino acids |
|
For bacteria to properly convert protein |
Need sufficient supply of energy - or valuable feed protein gets lost as ammonia |
|
Use bacteria and protozoa breakdown products to |
Form non-essential and essential amino acids which are then digested and absorbed |
|
Microbial Protein Digestibility (True Digestibility) |
Bacteria (75%), Protozoa (90%), Common total biomass (75-80%) |
|
Microbial Protein Amino Acid Concentration |
Can vary with diet;
Assumed constant at 80% or close to it;
Not all microbial protein is amino acids absorbed by the animal |
|
Not all feed protein degraded in the rumen |
Rumen undegradable or Rumen by-pass protein |
|
High quality protein sources may be |
Protected from rumen digestion |
|
Bypass protein |
Straight through the rumen and right on out - can be caused with increased feed amount |
|
Absorbed amino acids not used with 100% efficiency |
Not enough energy supplied by the diet;
Not correct ratios of amino acids supplied (amino acid profile wrong);
Animal over-supplied with protein |
|
Crude protein paths in ruminant: Rumen degradable protein |
Rumen degradable protein --> Microbial protein --> Microbial Nucleic Acids / Microbial true protein (AA) --> Amino acids absorbed in small intestine (68% used in tissue) |
|
Crude protein paths in ruminant: Rumen undegradable protein |
Rumen undegradable protein --> Undergradable protein amino acids (AA) --> Amino acids absorbed in small intestine (68% used in tissue) |
|
The PDI Protein System |
Protein system used for ruminants in Ireland - Feed analysis, Nutritional advice |
|
The PDI Protein System: Feed Component;
PDI Value = |
Protein value of ruminant diets;
Microbial amino acids absorbed from the small intestine;
Amino acids supplied by undegradable dietary protein and absorbed in the small intestine |
|
The PDI Protein System: Animal Component |
Animal requirement for amino acids;
Maintenance requirement;
Production (milk, weight gain, gestation, wool growth) |
|
PDI = |
g of true protein truly digestible in the small intesting;
the PDI is made up of two protein fractions: PDIM and PDIA |
|
PDIA = |
g of dietary true protein undegradable in the rumen but truly digestible in the small intestine |
|
PDIM = |
g of mircrobial true protein that is truly digestible in the small intestine |
|
Each feed has two PDIM values |
PDIMN and PDIME |
|
PDIMN = |
g of microbial true protein that can be synthesized in the rumen from rumen available N;
Depends on the rumen degradability of feed protein |
|
PDIME = |
g of microbial true protein that can be synthesized in the rumen from the rumen available energy;
Depends on the supply of fermentable organic matter (FOM) |
|
Each feed as a |
Potential and an actual PDIM value |
|
The higher of PDIMN and PDIME is |
The potential PDIM value |
|
The lower of the PDIMN and PDIME is |
The actual PDIM Value;
Consider how much you could produce, the lower is the actual value (rate limiting) |
|
The PDI System in Practice |
PDIME + PDIA = PDIE;
PDIMN + PDIA = PDIN |
|
PDIN = |
g of true protein (amino acids) truly digestible in the small intestine when rumen degradable N limited microbial protein synthesis |
|
PDIE = |
g of true protein truly digestible in the small intestine when rumen available energy (FOM) limited microbial protein synthesis |
|
The PDI value of a particular feed = |
The lower of the PDIN or PDIE value |
|
Peripheral neuro receptors stimulate the hypothalamus |
Receptors in liver, GI tract, Skin; |
|
Secretions of peptides and hormones directly on the hypothalamus |
Peptides from gut, adipose, brain |
|
Control of intake by additive effects of |
Peptides and Hormones and Neuro receptors |
|
Metaboli control of intake |
Circulating control of nutrients;
Peripheral neuro receptors in liver and GI tract;
Tell animal if there is lots or few nutrients in blood or gut |
|
Most likely feed intake regulator in monogastrics is (animal feel hungry when concentrations decline) |
Glucose |
|
Most likely feed intake regulator in ruminants is (animal feels hungry when concentrations decline) |
Acetate and proprionate from rumen; |
|
Animals with high energy / protein requirements (Lactating animals, rapidly growing animals) |
Strive to eat more |
|
Animals eat more after |
Starvation or excersize |
|
Lipostatic regulation of feed intake |
Desire to maintain constant body weight or fatness;
Lost in many domestic species, wild animals rarely obese |
|
Leptin |
Hormone produced by adipose tissue important for lipostatic control of feed intake --> satiety factor (Full feeling);
Leptin absent from obese mice |
|
Other lipostatic controls |
Adipose tissue in abdomen reduces intake;
Fatty acids in liver disrupt peripheral neural receptor system that initiates feeding |
|
Thermostatic regulation of feed intake |
Thermoreceptors in hypothalamus and peripherally in skin;
Food digestion produces heat increment;
Reduce feed intake if too hot;
Increase feed intake if too cold;
Lots of heat produced from excreting unwanted protein |
|
Physical limitations to feed intake |
Tension receptors in the oesophagus, stomach, duodenum, small intestine ;
Stomach and distal duodenum in dogs and cats;
Rumen in ruminants;
Crop in birds |
|
Physical limitations especially important in |
High fiber diets (balloon in ruminants);
Fiber limits intake in pigs, poultry, cats and dogs;
Very important in highly productive of very hungry animals - animals can be full up and still hungry |
|
Psychological factors regulating feed intake |
Sight of other animals eating;
Related to appetite;
Desire of animal to repeat pleasurable experience |
|
Photoperiod effect on regulation of feed intake |
Most evident in deer |
|
Effect of ill-health on regulation of feed intake |
Immune response: tumor necrotic factor; interleukins reduce intake;
Progesterone increases intake, estrogen reduces intake;
Stress hormone reduce intake;
Infectious disease, gastrointestinal parasites, parturition |
|
Feed intake regulators: feed factors |
Palatability;
Nutrient concentration;
Filling effect;
Physical factors |
|
Palatability of feed effect on feed intake |
Sensory response of an animal to its food; Taste, smell, sight, texture, temperature;
Appetite increases intake of palatable feeds;
Important hen choice available;
Companion animal feeds formulated to be palatable |
|
Nutrient composition of feed effect on feed intake |
High nutrient concentration may lower intake;
Marginal nutrient deficiency increases intake;
Severe nutrient deficiency reduces intake |
|
Filling effect of food effect on feed intake |
Related to fiber content - more fiber = more filling |
|
Physical factors of feed effect on feed intake |
Dusty feeds reduce intake (feed gone bad or mouldy or musty) |
|
Feed intake regulation: Management factors |
Feed allowance;
Frequency of feeding;
Feeding routine;
Feeding environment |
|
Feed allowance effect on feed intake |
Ad-libitum or restricted feed access;
To feed ad-libitum you must accept a 10% feed loss |
|
Frequency of feeding effect on feed intake |
Increased feeding frequency increases intake (Overall? Or in a singular feeding?) |
|
Feeding environment effect on feed intake |
Trough space (group fighting over food);
Previous experience at feed trough (traumatised by previous bullying);
Group stresses / group feeding can increase intake |
|
Feed intake prediction |
Intake predicted based on energy required and size [body weight, egg/milk production, growing animals (current vs mature size), heat stress]; |
|
Ruminants often fed high forage diets so |
Distention of the GI tract and filling effect of forage are very important factors |
|
Filling properties |
Neutral detergent fiber (NDF) (cellulose, hemicellulose, lignin) related to space occupying / filling effect of diet |
|
Digestibility of feed |
Indigestible material adds to the filling effect of the feed |
|
Rate of digestion in the rumen |
Room created more quickly for more feed |
|
Rate of digestion in the rumen |
Room created more quickly for more feed |
|
Rumen retention time of forage particles |
Particle size: most importnat with sheep |
|
The Fill Unit System for Ruminants |
Designed for forage based diet formulation |
|
Animal Intake capacity |
Quantity of food the animal can eat voluntarily |
|
Daily intake capacity |
Expressed in Fill Units: Lactation Fill Unit (LFU), Cattle Fill Unit (CFU), Sheep Fill Unit (SFU) |
|
Forage Fill Value |
The maximum quantity of forage that could be eaten when fed ad-libitum as the sole feed;
Expressed in Fill Units (LFU, CFU, SFU) per kg of feed;
Used in practice to predict daily intake of feed |
|
Substitution rate |
The influence of any supplementary concentrates required on the voluntary intake of forage |
|
The Full Unit: Animal Component
Intake capacity: Always daily intake capacity |
Weight of animal (related to rumen size / energy requirements);
Production level (milk);
Stage of lactation;
Fatness;
Breed |
|
The Fill Unit: Forage Component |
Forages are given fill values called Fill Units (FU);
Reference forage have 1.00 Fill Units;
All feeds expressed relative to the reference forage;
Mainly related to cell wall or filling effect of forage; |
|
When concentrate supplements are fed |
Total DM intake is increased, Forage DM intake is reduced |
|
Substitution rate = |
Reduction in forage DM intake per kg of concentrate DM fed;
Rate usually varies from 0 to 1.0 |
|
Substitution rate depends on |
Difference in energy required by animal, and energy supplied by forage alone;
Hungry animal low substitution rate, well fed animal high substitution rate;
Increased milk production or energy requirements leads to decreased substitution rate |
|
Substitution rate for high LFU forage is |
Less than substitution rate for lower LFU forages |
|
Mineral Types |
Macro minerals and Trace Minerals |
|
Vitamin Types |
Fat Soluble and Water Soluble |
|
Deficiencies in minerals cause |
Metabolic disorders |
|
Amount of mineral retained = |
Feed intake - faecal and urine output;
Feed is main intake;
Feed may contain minerals that interfere with absorption |
|
Short or long term imba;ances of minerals |
Body reserves may compensate for imbalances in short term;
Metabolic disorders occur when body reserves cannot be mobilised to balance intake and requirement |
|
Macro Minerals - Needed in high quantity |
Calcium, Magnesium, Phophorous, Sodium, Sulphur;
Usually have no issue getting plenty in the diet |
|
Calcium involved in |
Blood clotting, enzyme action, muscle contraction - milk fever;
Metabolisation from bone decreases with age - older animals more prone to milk fever;
Ca requirement at lactation about twice that amount needed in last week of pregnancy;
Calcium required for egg shell formation |
|
Calcium metabolism |
Tightly controlled (unusual for mineral);
Under control of 3 hormones - Calcitonin, Parathyroid hormone, Vitamin D3 (conversion to active form dependent upon magnesium) |
|
Hypocalcaemia |
Milk Ca output increases at calving;
Ca in blood falls;
Takes 24 hours for absorption to increase and 48 hours for bone to respond;
Delay causes drain on Ca and leads to hypocalcaemia |
|
Calcium deficiency in cows (milk fever) |
Most within 24 - 48 hours of calving;
Death due to bloat and decreased heart activity;
Low Ca can increase incidence of left displaced abomasum |
|
Prevention of Ca deficiency in cows |
Increase absorption efficiency of dry cow - restrict Ca intake to increase absorption efficiency;
Supplement Vitamin D3 - only give near calving;
Supplement magnesium - stimulates mobilization of bone Ca |
|
Prevention of Ca deficiency in cows
Part 2 |
Ca:P ratio is idea at 1:2; Ca absorption maximum - supplement P (expensive)?;
Calcium Supplements - Limestone (34% Ca), di-calcium phosphate (22% Ca) |
|
Prevention of Ca deficiency
Part 3 |
Cationic : Anionic Balance;
Acidification of diet before calving increases Ca uptake from intestine |
|
Magnesium |
Enzyme activator;
Nerve impulse control;
98% bound in bone and other tissues;
Needs continuous supply in diet - limited fee pool in circulation;
Availability 15-30% absorbed in rumen |
|
Magnesium deficiency in cattle and sheep |
Grass tetany (staggers);
Animals on spring grass (low Mg);
Sodium for Mg absorption may be low;
Slow development in cattle in autumn - if animal stops eating (bad weather) or handling stress;
Rapid action to death;
Mg is conserved in forage usually OK |
|
Mg Deficiency Prevention |
Feed concentrate higher in Mg during times of low grass Mg;
Mg bullets dissolved in the rumen;
Mg licks - Bitter so mask with molasses;
Mg in water;
Dust pasture with calcined magnesite (be careful cause rain will wash away);
Use potassium fertilizer in autumn |
|
Phosphorous |
Present in many essential body substances (Nucleic acids, ATP);
Primary deficiency results in poor thrift. Often associated with Ca deficiency;
P easy to measure in blood |
|
Dietary Phosphorous |
P requirements typically 80% of Ca requirement;
Grass has 50% as much P as Ca;
Cereals high in P and balance deficit;
All grass diet can be short of P;
Animals on non-cereal supplements (maize) can be short of P |
|
Sodium |
Major cation in blood;
Acid-base balance;
Transmission of nerve impulses;
Nutrient absorption across gut;
Deficiency results in reduced performance;
Salt |
|
Sodium deficiency |
Rare!
Spring pastures;
Caused by lots of potassium fertilizer - increases P uptake and reduces sodium uptake by plant |
|
Sulphur |
Essential for rumen micro-organisms;
Synthesis of sulphur containing amino acids (methionine and cystine);
Sheep with rapid wool growth need more sulphur;
Deficiency rare excess may affect availability of other trace minerals; |
|
Trace Elements |
Required in small amounts;
Involved with enzyme activity mostly;
Most not of practical significance;
Interactions between trace elements can alter absorption and availability;
Trace elements more necessary for growth - problems in growing not lactating animals |
|
Signs of trace element deficiency |
Very variable:
Reduced fertility;
Reduced growth rate;
Be sure it is primary cause of problem because it is often not |
|
Copper |
Iron incorporation to haemoglobin;
Enzyme systems;
Oxygen metabolism |
|
Signs of Copper deficiency |
Changes in coat color (lack of pigment);
Reduced fertility and ill thrift;
Regional problem with animals on home-grown feed;
Liver copper best indicator |
|
Copper supplementation |
Pasture dressing with copper sulphate;
In feed supplement (copper oxide, sulphate, proteinated copper);
Rumen bolus of copper oxide needles;
Injections (dont use in horses);
Toxicity (especially in sheep) |
|
Selenium |
Selenium and Vitamin E act as antioxidants;
Deficiency causes cell death (white muscle disease in calves);
Sub clinical deficiency common - poor growth, increased mastitis;
Glutathione peroxidase used as indicator to measure selenium;
Selenium toxicity in horses - regional (some weeds accumulate Se) |
|
Selenium supplementation |
Improved fertility;
Less retention of foetal membranes;
In feed - sodium selenite, proteinated forms;
Rumen bolus;
Injection;
In anthelminthic - Panacur SC |
|
Cobalt |
Needed for synthesis of vitamin B12;
Deficiency - poor growth, susceptible to parasites, ketosis and weight loss in cows, can be induced by high Mn;
Not measured in blood but response to supplementation observed;
Supplement with cobalt sulphate |
|
Zinc |
Deficiency causes - skin lesions, ill thrift, lameness (keratin synthesis), mastitis, unlikely to be common deficiency;
Supplements - Zinc oxide, sulphate, Zinc Mthionine Proteinate |
|
Iodone |
Involved in thyroid hormone formation;
Primary deficiency or secondary due to Giotregens in feed (kale, cabbage);
Deficiency - reduced fertility, week and hairless young born, regional |
|
Iodine deficiency |
Diagnose at post-mortem by weight of thyroid gland (large if low iodine);
Herbage low;
Supplement - potassium iodide, calcium iodide, iodized salt lick, seasweed meal;
Accumulates in milk - toxicity? |
|
Iron |
Formation of haemoglobin;
Deficiency - anaemia (not common);
Soil contains iron - housed animals on all milk diet develop deficiency (pigs);
Excess iron can reduce copper uptake |
|
Manganese |
Enzyme activator;
Deficiency - impaired fertility and growth;
Supplement with manganese oxide or manganese sulphate;
Proteinated manganese |
|
Mineral stores |
Good storage - Ca, P, Na, Cu, Se - if deficient for weeks, no great problem;
Medium Store - I - protected for 2-3 weeks;
Poor store - Mg, Co - need daily supplement |
|
Proteinate versus inorganic form |
Mineral bound to amino acid or small protein;
Absorption like peptide not mineral;
Maintains more bioactivity;
Cost ?
Cu, Zn, Mn |
|
Vitamins |
Organic molecules required in small amounts;
Supplementation usually generous to cover all conditions;
Fat soluble - A, D, E, K;
Water soluble - B complex, C |
|
Vitamin A (Retinol) |
Carotenoids in green plants precursors for vitamin A give yellow colour to milk, fat;
Involved in maintenance of epithelial cell lining and vision;
Often supplemented - not toxic till over 100x recommended value;
Degrades over time - supplement on non-green food |
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Vitamin D3 |
Involved in calcium regulation;
High in hays and can be synthesised in skin from UV;
Deficiency - rickets;
Toxicity due to overdose in treatment of milk fever;
Often supplemented dirrectly - winter no UV, housed animals |
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Vitamin E (alpha tocopherol) |
With selenium acts as antioxidant;
Present in fresh green feed drops in storage (silage low);
Deficiency more common after winter - muscle weakness, sudden death;
Supplement either vitamin E directly or selenium;
Unstable in moist feed - proprionic treatment of grain destroys it;
High fat diet needs more vitamin E |
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Vitamin K |
Synthesized by rumen bacteria;
Involved in blood clotting;
Primary deficiencies rare;
Some clover hay contains warfarins that block clotting mechanism - vitamin K is antidote in dogs |
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Vitamin B complex |
Range of vitamins act as co-enzymes;
Ruminants synthesize B vitamins by rumen microbes;
Synthesis needs cobalt;
Thiamine (vitamine B1) deficiency where thiaminase activity high (sugar/starch diet acidosis);
Result in cerebro-cortical necrosis |
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Vitamin B Complex Part 2 |
B1 and B12 occasionally supplemented in cattle and horses;
Common supplement in pig and poultry rations;
Appetite stimulants? |
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Vitamin C (ascorbic acid) |
Most can synthesize (except human and guinea pig);
Deficiency in farm animals rare! |