Preference of weanling pigs for dietary supplemental methionine sources

Three hundred and sixty pigs were used in a study to determine whether the dietary inclusion of DL-methionine reduces diet acceptance by weanling pigs and how other commercial sources of supplemental methionine compare. During the first, third and fifth week following weaning at 21 days of age, pigs were offered a choice between a basal diet (control) or basal diet supplemented with DL-methionine, liquid methionine or liquid methionine hydroxy analogue (MHA), with or without a flavoring/aromatic agent. Daily feed disappearance was used as an indicator of diet preference. The diet supplemented with DL-methionine was preferred by pigs over the control diet for the first 3 days following weaning. Both the DL-methionine and the liquid MHA supplemented diets were preferred during the last 3 days of the first week of the study. The dietary addition of DL-methionine, liquid methionine or liquid MHA increased the preference of pigs for these diets compared with the basal control diet during the entire third and fifth week. The results indicate no adverse effect of these supplemental methionine sources on the diet preference of nursery pigs. The dietary addition of the flavouring/aromatic agent used in the present study reduced the preference of pigs for the treatment diets irrespective of the supplemental methionine source.