The presence of experienced piglets does not promote the growth of newl weaned piglets

In a feeding trial the hypothesis was tested that the presence of experienced piglets facilitates the adaptation of newly weaned piglets to solid food. The 72 four-week-old piglets in the experimental group were mixed at weaning with 12 piglets which had been weaned one week earlier, whereas their 72 siblings in the control group were reared in the absence of experienced piglets. Observations between the second and fourth day showed that the experimental piglets displayed eating behaviour more frequently than the control piglets. During the first week, diarrhea prevalence was higher (35 vs. 25 animals; P = 0.09) and daily weight gain was lower (11 g vs. 29 g; P = 0.10) in the experimental group than in the control group. Weight gain during the whole five-week experimental period was practically identical (P = 0.90). The negative effect of the experienced piglets can possibly be attributed to their shedding of entero-pathogens and the increased food intake of the newly weaned piglets before their gastrointestinal tract was adapted to solid feed, thus increasing the diarrhea risk in the experimental group.