HOMEWORK # 1 - PROXIMATE ANALYSIS and TDN
A FARMER HAD A FEEDSTUFF WHICH HE SENT TO A LABORATORY FOR PROXIMATE ANALYSIS. IT WAS GROUND AND A 200 GRAM SAMPLE WAS WEIGHED INTO A PAN AND DRIED IN AN OVEN UNTIL CONSTANT WEIGHT WAS ATTAINED. THE DRY WEIGHT OF THAT SAMPLE WAS 181 GRAMS.
ANOTHER 200 GRAM SAMPLE WAS WEIGHED AND KJELDAHL ANALYSIS RUN. FROM THAT SAMPLE 4 GRAMS OF NITROGEN WERE OBTAINED.
A DIFFERENT 300 GRAM SAMPLE WAS WEIGHED, DRIED, WEIGHED ( 271.5 GRAMS), ETHER WAS REFLUXED THROUGH THE SAMPLE, THEN IT WAS DRIED AND WEIGHED AGAIN AND IT WEIGHED 257 GRAMS.
THIS SAMPLE WAS BOILED IN DILUTE ALKALI, THEN DILUTE ACID, THEN WASHED, THE RESIDUE DRIED, WEIGHED (IT WEIGHED 24 GRAMS) AND PLACED IN A CRUCIBLE IN A FURNACE AT 550 C AND ASHED, COOLED, AND WHAT WAS LEFT WEIGHED .8 GRAMS.
An additional 300 g sample was ashed and it weighed 2.533333 g
WHAT IS THE PROXIMATE ANALYSIS OF THIS FEEDSTUFF THAT SHOULD BE REPORTED TO THE FARMER?
Water
Crude Protein
Ether Extract
Crude Fiber
Ash
NFE
Total 100
Assume the digestibility of Crude Fiber is 50%,
of Ether Extract is 70%, and of CP and NFE is 80%.
What is the TDN value of the feed?
TDN
