The AAT/PBV protein evaluation system for ruminants. A revision
Year: 1995
Type: other
Abstract: The AAT/PB V protein evaluation system for ruminants has now been used in Denmark, Norway and Sweden for some years and will soon be introduced in Finland and Iceland as well. The basic concepts\nwith AAT (amino acids absorbed in the small intestine) and PB V (protein balance in the rumen) and the\nfactors to be considered in predicting the AAT and PBV values are maintained, but the continuous development in methods and knowledge has led to changes in methods used to predict the individual\nfactors. The inclusion of these modifications in the different countries has not taken action at the same time, but depends on the time the different countries has introduced the system and on the calendar for\nmajor changes in the feed evaluation system. It has the effect that at a given time the system may be slightly different in the different Nordic countries. but we follow the same line in the development. The\nfollowing is the most important changes that has been made or arc going to be made in the system since\nthe system was first presented. In the prediction of the AAT and PBV values of the feeds: I) changes in\nthe nylon bag procedure to predict the protein degradability in the rumen by correcting for particle loss\nand for microbial N contamination of the bag residues in fibrous feeds, 2) a change from using a constant\nfigure of 0.82 for intestinal digestibility of undegraded amino acids to an actual determination of the\nintestinal digestibility of the single feeds. 3) a microbial amino acid synthesis per kg of digested\ncarbohydrates on fresh grass of 135 g is used instead of the general factor of 125 g which is maintained\non all other feeds. The recommendations for AAT and PB V to different categories of ruminants will depend on the actual economical situation and feeding system and will therefore differ from place to place and probably from time to time as well. In general, it has been observed that the potential of decreasing the protein allocation is greater than the possibilities of increasing the milk yield or the weight gain. by using the AAT/PBV system instead of the digestible crude protein system.
Language: English
Topic: Animal health and immunology
Subfield: Animal Science and Zoology
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W2273990572