Effects of auditory, visual and chemical stimuli on the ingestive behavior of newly weaned piglets

Auditory, chemical and visual stimuli were used in a factorial trial in an attempt to stimulate feeding in newly weaned piglets. Ninety-six crossbred piglets weaned at 28 d of age were assigned to groups containing four littermates. Each group was placed in a 1.2-m X 1.2-m pen in an isolated room for 48 h. Pens were equipped with nipple waterers and trough-type feeders. The auditory stimulus was piglet and sow nursing vocalizations. A visual stimulus was provided by a lamp that illuminated the feeding area. Auditory and visual stimuli were presented for 5 min once an hour for 48 h. The chemical stimulus consisted of 60 ml of evaporated milk sprayed over the surface of the feed once every 12 h. Water was used in place of milk in control treatments. Piglets were videotaped for 48 h. Frequency and duration of feeding, drinking and lying were recorded for two piglets out of each pen. Auditory stimuli increased (P less than .05) the number of drinking bouts per day from 16.3 to 19.2 and the number of drinking bouts associated with stimulus presentation from 6.2 to 8.0. There also was an auditory X day interaction effect on total time spent feeding. On d 2 postweaning piglets in the auditory treatment group spent more (P less than .05) time feeding than did those without auditory stimulation (127.1 vs 104.2 min, respectively). The relatively simple visual and chemical stimuli tested had no significant effects on ingestive behavior.(ABSTRACT TRUNCATED AT 250 WORDS)