Feed Analysis – Week 9 Go Over Exam 2 Discuss Exam 3 Terminology Haylage Lab Wrap Up Next Feed Analysis Lab – Dry Hay and Scissor Cuttings – Next Week Wednesday This Week – Digestion Lab Look at PPT from More – To – Do Farms Proximate Analysis – Today Digestion Calculations and NPU

What is Proximate Analysis? Proximate Analysis is a partitioning of compounds in a feed into six categories based on the chemical properties of the compounds. The six categories are: 1.moisture 2.ash 3.crude protein (or Kjeldahl protein) 4.crude lipid 5.crude fibre 6.nitrogen-free extracts (digestible carbohydrates)

Moisture – You already know this….

To determine Ash: What is ASH? Burn sample by placing a weighed amount into a muffle furnace for 2 hours at 600 degrees C. Ash is considered as the dry “inorganic” residue remaining. What has been removed? What is remaining?

To determine Crude Protein: Digest a small dried sample in concentrated sulfuric acid until all organic matter is destroyed. Nitrogen from feed is now in the form of ammonium sulfate. The digest is neutralized with sodium hydroxide, distilled, and the titrated. Protein contains an average of ______ % N. 100/16 =

To determine Ether Extract: Extract dry sample with Ether for a period of 4 hours or more. This removes the fat only, thus the loss of weight after drying equals fat.

To determine Crude Fiber: After removal of water and ether extract from a sample of feed, the sample is boiled in weak acid(.0255 N H2SO4), then in weak alkali (.312 N NaOH). This removed the proteins, sugars, and starches, which are discarded. What’s Left? ___________________ - Then What? _________

To determine NFE: Nitrogen Free Extract is found by difference, not by actual analysis. The percentages of water, ash, protein, fiber and fat are merely added together and subtracted from 100. The NFE is made up of readily available CHO’s. Such as: _______________ and _____________ .

To determine NFE: Nitrogen Free Extract is found by difference, not by actual analysis. The percentages of water, ash, protein, fiber and fat are merely added together and subtracted from 100. The NFE is made up of readily available CHO’s. Such as: _______________ and _____________ .

To determine Energy: The bomb calorimeter is an instrument used for determining the gross energy content of a material. Energy Value is expressed in units called ____________ . Where 1 calorie is the amount of heat required to raise the temperature of 1 gram of water from 14.5 degrees Celsius to 15.5 degrees Celsius. Cal- Kcal = Mcal =

To determine Digestibility : IN A PERFECT WORLD ????????? Brainstorm how to get this info……….

To determine Digestibility : IN A PERFECT WORLD ????????? - Indicator - Feces Collection Bags -Digestion Stalls - In a lab????

To determine Digestibility : A Digestion Trial Consists of: 1. Running a proximate analysis of feed 2. Feeding an animal a given amount of feed 3. Collecting Feces from a given amount by use of a marker or collecting feces. 4. Running an proximate analysis of feces 5. The difference is the apparent digestible portion of the feed. 6. Computed as follows:

To determine Digestibility : Equation: Nutrient Intake - Nutrient in Feces Apparent digestibility (%) = __________________________ X 100 Nutrient Intake

To determine Digestibility : Now an example: Wednesday Lab: