FEED FORMALUATION USING THE ITERATION METHOD
This application is a simple feed formulation program.
It is designed for Animal Nutrition lecturers, farm animal producers, animal practitioners, nutritionists and consulting veterinarians who want to use an easily to use try and error spread sheet feed formulation program.
The program has three sheet and you can move from The Data Entry Sheet to formulate sheet and then to the Output or Result sheet and back until you get the solution that fit your situation.
Data Entry Sheet
Data Entry Sheets enable you to use data in the already put in software for Dry Matter (DM), Crude Protein (CP), Crude Fibre (CF) and Cost per tone or change raw material attributes. You enter your own ingredients and their chemical composition by overtyping, and these will be updated automatically in the Formulate and Output sheets. It is recommended that you enter values on a dry matter basis. Formula Price
The formulation method is the iteration (i.e. try and error) automated by a spreadsheet. Enter inclusion rates or proportion values (as %) against the raw materials of interest sticking to standard rules of thumb in feed formulation (see notes on RED tabs in the Formulate sheets). Through iterations (a few trials) you will be able to produce the diet of interest. As you enter the proportions the total % inclusion is summed up automatically for you so that you can adjust % levels until its 100%.
The formulation Basis provides options for "As-Fed Basis" or "Dry Matter Basis". When entering nutrient composition, you must decide the basis you will work with although it is recommended to use the Dry Matter basis. This is a very critical point. An improper selection of basis will result in an incorrect formula. The resultant formula should be on same basis as that of nutrient requirements. For example, if nutrient requirements are considered on "As-Fed Basis", the formula will be on "As-Fed Basis" too. To change DM basis to As Fed Basis and vice versa the following formulae are useful:
The method of converting from one basis to the other is as follows:
Let A = be kilograms of feed on 100 percent dry matter basis
B = kilograms of feed on an as fed basis
C = the percent of dry matter in the feed
To convert from as fed basis to 100 percent dry matter basis:
A = B x C
Example: A ration calls for 2.6 kg of maize on as fed basis. The feed composition table shows that maize has 89 % dry matter. Therefore 2.6 x 0.89 = 2.3 kg on a 100 percent dry matter basis.
To convert from 100 percent dry matter basis to as fed basis:
B = A/C
Example 1: A ration calls for 2.3 kg of maize on a 100 percent dry matter basis. The feed composition table shows that maize has 89 % dry matter. Therefore 2.3/0.89 = 2.6 kg on as fed basis.
Example: A ration calls for 9 kg of alfalfa on a 100 percent dry matter basis. The feed composition table shows that alfalfa at mid bloom has 89.2 % dry matter. Therefore 9/0.892 = 10 kg on as fed basis.
NB: When using nutrient requirement and feed composition tables given on a 100 percent dry matter basis, it is easier to work out the ration on the dry matter basis and then convert the final figures to as fed (air dry) basis.
Out put Sheet
This gives you the properties of the diet you have formulated which you compare against specifications (see best results table at the right hand top position). The bigger table to the left gives more details on the contributions of each ingredient to Dry Matter, Crude Protein, Crude Fibre and Cost. So you can use these contribution values to reformulate. If say the diet is too expensive, you can lower the proportion of the ingredient that has contributed more cost. Reformulate a few more times and until you get the diets that suits your situation. This is called iteration.
The price per unit of the calculated formula appears in the best result table. No units for weight or currency are mentioned here so you can use your own currency units. The weight and currency units are same which are used in the Data Entry Sheet (database). For example if ingredient price is entered in Ãƒï¿½Ã‚Â£ /kg, the price of the formula will also be in Ãƒï¿½Ã‚Â£ /kg. If ingredient is entered in $ /ton, the price of the formula will also be in $ /ton. Because this software does not take currency units in consideration while making formula, it is important that all price values should be entered in the same units throughout the programme.
If you want to create a bank of formulae (historical formulae) for future reference, click on File, then Save as and type a different file name, create a folder named Historical formulae and save your files in here. These files can be accessed via Excel.
To Print active sheets, Click on File then Print and choose Active sheet. To print all the three (Data entry, Formulate and Output sheets) choose Entire workbook.