Belly-nosing in early-weaned piglets is not influenced by diet quality or the presence of milk in the diet

Early weaning of piglets can lead to an increase in belly-nosing and other oral-nasal behavior (nosing, chewing, or sucking other piglets), but the causative factors involved in these behavior patterns are largely unknown. Because these behavior patterns resemble massaging the udder and sucking, they may be associated with feeding. The objectives of this study were to determine any effect of diet quality or the presence of milk in the diet on belly-nosing behavior of piglets weaned at 14 to 18 d. During the first 2 wk after weaning, piglets were fed diets differing in quality and inclusion of milk products. Six replicates of eight piglets per replicate, blocked by initial body weight, (n = 192) were offered one of four dietary treatments: HQM: high quality, high in milk products; HQ: high quality, no milk products; PQ: poor quality, no milk products; HQ+MR: high quality, no milk products (as HQ) sprayed with milk replacer five times daily. Thereafter, the piglets were fed a standard nursery diet. Feed intake was measured daily for wk 1 and again at the end of wk 2. Behavior was recorded every 5 min during two 4-h periods on d 2 to 7, 10, 14, 17 and 21 after weaning. Dietary treatment influenced ADFI and ADG during wk 1. Average daily feed intake (P < 0.05) and ADG (P < 0.05) of piglets on PQ were less than those of piglets on the other treatments. During wk 2, ADFI (P > 0.10) and ADG (P > 0.10) were the same across all treatments. Overall, ADFI was not influenced by the inclusion of milk products in the diet or the addition of milk replacer (P > 0.10); however, ADG was. Piglets on HQM had higher ADG than those on HQ during wk 2 (P < 0.05) and 3 after weaning (P < 0.05). However, milk replacer did not influence ADG (P > 0.10). Although the dietary treatments did affect ADFI and ADG, there were no effects on any behavior pattern recorded, including time spent at the feeder (P > 0.10). Lower weight-for-age piglets performed more oral-nasal behavior, in total, than higher weight-for-age piglets (P < 0.03). Neither feeding a poor-quality diet nor the presence of milk in the diet had an effect on belly-nosing or other oral-nasal behavior patterns during the first 3 wk after weaning. Belly-nosing does not seem to be associated with feeding.