The effect of lysine/energy ratio on the performance of weaned piglets. Influence of using the post weaning diet up to 40 kg

Three hundred and sixty weaned piglets, with an average body weight of 7.2 kg, were allocated to treatments to determine the optimum ratio of digestible lysine/net energy (digest lys/NE). Four treatments were compared in a 2 x 2 factorial design : two net energy levels, 2300 and 2200 kcal/kg and two digest lys/NE ratios, 4.9 and 5.8 g/1000 kcal.The diets contained maize, wheat, barley and soybean meal. Feed intake was not affected by dietary energy content and digestible lysine level.When the energy in the diet increased, ADG increased and feed conversion ratio was improved. The optimal digestible lysine content of the diet and the optimal digestible lysine/net energy ratio appeared to be, respectively, 11.5 g/kg and 4.9 g/1000 kcal.The distribution of the post weaning diet up to 40 kg, meant that the piglets were better adapted for the finishing period.Overall growth performance and feed conversion ratio were very similar whatever the post weaning diet.