WEEK 3: Nutrition / Feed Analysis Flashcards
Anabolism
Synthesis of complex molecules to store energy
Catabolism
Breaking down complex molecules to produce energy
Eructation
Burping lol
Diet vs. Ration
Diet is all the feed and water consumed by an animal.
Rations are the daily feed allotment given to an animal.
Aspects of Feed Analysis
> Nutrient composition
Digestibility
Productive value
Palatability
Physical characteristics
Proximate Analysis of Feeds
A set of traditional chemical/analytical procedures designed to partition feedstuffs into various nutrient components including water, ash, crude protein, ether extract, crude fiber, and nitrogen-free extract.
Dry Matter
Everything in a feed other than water. Found via evaporating all the water out of a sample.
Ash
The mineral content of the feedstuff. Determined by literally burning off all organic matter in a feed sample.
Crude Protein
An estimate of the protein content in a feed sample. Found via math based on the nitrogen content of the sample, but because not all of the nitrogen is derived from protein, it’s a crude measurement at best.
Ether Extract
Crude fat. Found by using a fat solvent to extract fat from a sample.
Crude Fiber and Nitrogen-Free Extract
Provide an estimate of the carbohydrates in a feed.
Limitations of Proximate Analysis
Information is sometimes misleading or inaccurate
* Crude protein measurement has little value for monogastric animals and immature ruminants
* Some plant materials other than fat are also ether soluble
* Nitrogen-free extract (NFE) is often an inaccurate estimate of digestible carbohydrates
Van Soest Method
Some complex bullshit, an “alternative fiber analysis” that helps predict how digestible feedstuff will be for animals and “evaluate heat damage in forages”
Feed Analysis of Vitamins
Vitamins must be individually assayed to determine concentrations in feed. Biological assays for some, chemical analysis for others.
Feed Analysis of Energy Content
BOMB CALORIMETER BABY
Determines gross energy of a sample in calories.
Calorie: energy required to raise temp of 1g of water by 1 degree Celsius
3 Ways to Determine the Value of Feedstuffs to Animals
1) Feeding Trial
2) Digestion Trial
3) Metabolism Trial
Feeding Trial
A comparatively simple experimental tool in which animals are fed to determine their performance on specific feeds or substances added to feeds.
AKA “Will they eat it? What happens when they do?”
Digestion Trial
An experimental tool used to determine the digestibility of a specific feedstuff, nutrient, or ration.
AKA Chemically analyze the nutrients in a feed/diet, feed it to an animal, collect its poop, and then compare what nutrients remain in the poop to what was in the feed originally.
The digestion coefficient refers to how much of the feed has been absorbed nutritionally.
TDN = total digestible nutrients
Metabolism Trial
An advanced form of digestion trial that measures the body’s use of nutrients
Two expressions of feed composition
Air-dry Basis (as-is) and Dry Matter Basis
Units of Energy Measurement
Kilocalorie (kcal) - 1000 calories
>used in Human and Pet nutrition
Megacalorie (Mcal) - 1,000,000 calories
>used in Livestock nutrition
Energy Content of Nutrients
CARBOHYDRATES - 4 kcal/g
PROTEIN - 4 kcal/g
FAT - 9 kcal/g
“four four nine” with fat as the densest. ez pz.
Ration (Balanced)
The amount of feed offered to an animal during a 24-hour period.
Balanced ration: provides the proper nutrients for an animal to accomplish its specific production function
High Quality Rations
1) Palatable
2) Economical
3) Free of quality-lowering factors
National Research Council
Publishes nutrient requirements and recommendations for feeding
animals in various stages of production
Covers animals used in agriculture, research, and as companions.
