Controlled versus and ad libitum feding


  • When the amount of feed consumed is regulated in some way by the experimenter,the feeding is controlled, as distinguished from the ad libitum system in which each animal or group is allowed to eat all it wants.
  • Ad libitum feeding, or ¬†unrestricted feeding of animals is the most commonly followed procedure in farm animal investigations and gives unbiased results for direct practical application.
  • By keeping records of feed intake,the results can be expressed on an efficiency basis, such as "feed required per 100 kg gain" as well as in terms of total increase in weight.This system gives unbiased results for direct practical application in terms of the feed, species and function under study.
  • It is subject to the limitation, however, that with certain feeds and rations differences in nutritive value may be masked by differences in palatability.Further, the method does not provide the controlled conditions required for certain purposes-for example, the deterimination of digestibility.
  • Thus, in many instances there is an advantage in using some system of controlled feeding. Earlier in their studies of protein quality, Osborne and Mendel recogonised that ad libitum feeding, frequently gave rise to variable results.
  • In one series of studies Osborne and Menedel kept the food intakes alike for each diet under study, in accordance with a prescribed schedule¬†based upon the preliminary experiment.
  • They were thus able to compare the growth made on different diets consumed in the same amount.Recognising that the more rapidly growing animals might be at a disadvantage under this system in view of their increasing maintenance requirement.
  • They carried out another series in which the food intake was adjusted in accordance with increase in weight.
  • In another experiment Osborne and Mendel allowed¬† ad libitum feeding and selected for comparison the growth records of those animals which had consumed substantially the same amount of food under this system.
  • Ad libitum gives unbiased results for direct applications
  • Ad libitum feeding does not provide the controlled conditions required for certain purposes like the determination of digestibility.

Ad libitum feeding of goats

  • Ad libitum feeding frequently gives rise to variable results.
Last modified: Monday, 6 February 2012, 8:37 AM