Impact of a short term dietary challenge on growth performance and feeding behavior in finishing pig

Pigs are frequently facing environmental perturbations with subsequent short and long-term effects on their health and performance. The objective of this study was to evaluate the consequences of an acute dietary challenge on growth performance and feeding behavior in finishing pigs. A total of 160 pigs (average initial BW of 69.1 kg, 115 d of age) were used in two successive replicates of 80 animals with 4 treatments. In the control group (CC), pigs were fed a standard diet (7.6 g digestible Lys/kg and 9.6 MJ NE/kg) during the whole experimental period (55 days). The DC, CD, and DD groups were challenged with a ‘diluted’ diet for a 7-d period at 130 d, at 153 d, and at 130 and 153 d of age, respectively. Digestible Lys and NE contents were reduced by 20% in the diluted diet in comparison to the control diet, using wheat bran and sunflower meal as diluters. In both diets, essential amino acids were kept constant relative to Lys. Within each replicate, all pigs were equipped with a RFID ear-tag and housed in a same room. The room consisted of a resting area and 2 feeding areas separated by a weighing-sorting station, which allowed for continuous measurements of individual BW. The 2 feeding areas were equipped with 4 feeding stations each. These electronic feeder systems automatically distributed the chosen diet to each pig and recorded the visits to the feeder, with their time and the amount of feed consumed. The average daily BW gain and the BW at slaughter were significantly reduced in the CD and DD groups when compared to the CC group (1,052 g/d and 125.5 kg on average vs 1,119 g/d and 129.5 kg, respectively; P<0.01). Intermediate results were reported for DC group (1,073 g/d and 127.1 kg). Feed conversion ratio was higher in DC and DD groups than in CC and CD groups (3.13 and 3.15 vs 2.93 and 2.95 kg/kg, respectively; P<0.01). Over the total duration of the experiment, mean feeding behavior traits were not influenced (P>0.05) by treatments. Carcass traits were similar in the 4 experimental groups. This study demonstrates an age-of-exposure effect of a dietary challenge on growth performance in finishing pigs. This study is part of the Feed-a-Gene project and received funding from the European Union’s H2020 program under grant agreement no. 633531