Nutritional plans of net energy with a constant calorie: nutrient ratio on the performance of piglets from 7 to 30 kg

ABSTRACT

This study was conducted to evaluate different nutritional plans of net energy (NE) with a constant calorienutrient ratio on the performance of piglets from 7 to 30 kg. Sixty barrows with an initial weight of 7.11±0.89 kg were distributed among five nutritional plans two NE-decreasing plans (A and B, starting from NE concentrations of 2.47 and 2.52 Mcal kg−1, respectively, and ending both at 2.37 Mcal kg−1) and three NE-constant plans (C, 2.37 Mcal kg−1; D, 2.42 Mcal kg−1; and E, 2.47 Mcal kg−1). The nutritional plans were composed of two decreasing plans A, 2.47-2.42-2.37- 2.37-2.37 Mcal of NE kg−1 of feed; B, 2.52-2.47-2.42-2.37-2.37 Mcal of NE kg−1 of feed; and three constant plans C, 2.37 Mcal of NE kg−1 of feed; D, 2.42 Mcal of NE kg−1 of feed; E, 2.47 Mcal of NE kg−1 of feed, from 7 to 10, 10 to 15, 15 to 20, 20 to 25, and 25 to 30 kg, respectively, with six replicates per treatment and two animals per experimental unit. Animal performance was evaluated through the following measurements average daily feed intake (ADFI), NE intake, standardized ileal digestible lysine intake (SID Lys intake), average daily gain (ADG), feedgain ratio (FG), final weight (FW), feed cost per kg of weight gain (CWG), economic efficiency index (EEI), and fecal score. Piglets' final weight was 32.95±3.30 kg. Considering the total experimental period, there was no effect of the nutritional plan on ADG, FG, CWG, and EEI. The final weight of piglets under plan D was higher than that recorded for those allocated to plan C, not differing from the other nutritional plans. Piglets fed under nutritional plans A and D presented higher ADFI compared with those subjected to other plans. Net energy and SID Lys intakes were significantly higher in piglets subjected to plans A, D, and E compared with those under plans B and C. Net energy nutritional plans did not influence the fecal score and the occurrence of diarrhea of the piglets. Based on our analysis, a nutritional plan containing a constant NE level of 2.42 Mcal kg−1 of feed may be recommended for piglets from 7 to 30 kg.