The effect of creep feed intake and starter diet allowance on piglets' gut structure and growth performance after weaning.

Diets offered to lactating and weaned piglets are the most expensive diets within pig production; however, the effect of these diets on lifetime pig performance is inconsistent. The objective of the current study was to investigate the impact of creep feed consumption during lactation and different starter diet allowances on piglets' gut structure and lifetime growth performance. In total, 320 pigs and 80 pigs (Landrace × Large White) were used after weaning in a 2 × 2 factorial arrangement to study growth performance and gut structure, respectively. At weaning, piglets that ate creep feed and piglets that were not offered creep feed during lactation were allocated to 2 kg/pig [low level (LL)] or 6 kg/pig [high level (HL)] of starter 1 diet (16.5 MJ DE/kg, 22.5% CP, and 1.7% total Lys) allowance. At weaning and at 1 and 3 wk after weaning, 8 piglets per treatment were sacrificed, and their small intestine morphology was evaluated (villus height and crypt depth). Piglets that ate creep feed had increased feed intake during the first week after weaning (P < 0.05), but no effect of creep feed intake was observed on piglets growth or gut structure during the postweaning period (both P > 0.05). Piglets that were fed HL after weaning had higher ADG and BW from weaning to 16 wk after weaning (both P < 0.05) and had lower feed conversion ratio (FCR) from weaning to 6 wk after weaning (P < 0.05). Piglets fed HL after weaning also had higher villi height and greater crypt depth than LL piglets at 3 wk after weaning (both P < 0.05). Creep feed consumption during lactation increases feed intake early after weaning, suggesting an improved capacity of piglets to cope with weaning, but did not influence their growth performance. Offering piglets 6 kg of starter diet enhances piglets' growth performance during the growing and finishing phase, probably by improving gut structure after weaning.