Pigs receiving daily tailored diets using precision-feeding techniques have different threonine requirements than pigs fed in conventional phase-feeding systems

Abstract

Background There is large variation in amino acids requirements among pigs, hence feeding pigs individually with daily tailored diets or in groups with a single feed may require different levels of nutrients. Thus, the response to different threonine levels (70%, 85%, 100%, 115%, and 130% of the ideal threonine:lysine protein ratio of 0.65) was studied in growing pigs raised in a conventional group phase-feeding (GPF) system or fed individually using individual precision-feeding (IPF) techniques. In a 21-day trial, 110 barrows (25 ± 0.80 kg body weight) were housed in the same room and fed using electronic feeders. Five pigs per treatment were slaughtered at the end of the trial. Results Threonine intake increased linearly for the IPF and GPF pigs ( P < 0.05). Lysine intake was similar across the treatments. Average daily gain, gain:feed ratio, and protein deposition were affected linearly by threonine level ( P < 0.05) in both feeding systems. Protein deposition in the GPF pigs was maximized at 150 g/d and a 0.65 threonine:lysine ratio, whereas protein deposition increased linearly in the IPF pigs. Plasma Met and serine levels were 11 and 7% higher, respectively, in the IPF pigs than in the GPF pigs ( P < 0.05). Dietary threonine increased ( P < 0.05) threonine concentration in the longissimus dorsi in a quadratic manner in the IPF pigs, whereas there was no effect in the GPF pigs. Longissimus dorsi collagen decreased as dietary threonine increased in the IPF and GPF pigs ( P < 0.10). Carcass muscle crude protein was 2% higher in the GPF pigs than in the IPF pigs ( P < 0.05). Conclusions Individual pigs are able to modulate growth and the composition of growth according to threonine intake. The average amino acid ratio value that is currently used for GPF cannot be used for IPF.

Feeding behavior of growing and finishing pigs fed different dietary threonine levels in a group-phase feeding and individual precision feeding system

“…A total of 220 barrows of the same high-performance genotype (Fertilis 25 × G-Performer 8.0; Geneticporc Inc., St-Gilbert, Quebec, Canada) with a good health status were shipped to the Agriculture and Agri-Food Canada swine complex (Sherbrooke, Quebec, Canada) in two batches. Each batch of pigs was part of a different animal trial with a batch of 110 pigs in the finishing phase [110–130 kg body weight (BW); November to December 2015 ( Remus et al, 2020a )] and a batch of 110 pigs in the growing phase (25–50 kg BW; February to March 2016; Remus et al, 2019a ). Pigs were allocated to two 76-m 2 pens each with a concrete slat floor in the same mechanically ventilated room.…”

“…Individually fed pigs in a precision feeding setup have higher amino acid (AA) efficiency of utilization than pigs fed in groups in conventional phase-feeding systems ( Cloutier et al, 2015 ; Remus et al, 2019a ). This is due to the fact that group-fed pigs receive larger and constant amounts of AA within each feeding phase to maximize herd growth performance.…”

“…Most of the pigs fed with precision feeding systems receive smaller amounts of AA than the group-fed pigs, and dietary AA concentration decreases as the pigs age ( Andretta et al, 2014 , 2016b ). Precision feeding system decreases AA intake from 17% ( Remus et al, 2019a , 2019b ) to 27% ( Andretta et al, 2014 , 2016b ), and further changes in dietary threonine (Thr) ( Remus et al, 2019a ) might impact on feeding behavior. Early studies ( Yoshida et al, 1966 ; Benevenga et al, 1968 ) have proposed that drops in plasmatic Thr or histidine due to AA imbalance increased the efficiency of utilization of these AA.…”

“…Previously, we demonstrated that pigs can change body composition as a function of Thr intake and feeding system (group-fed vs. individually fed pigs; Remus et al, 2019a ). However, body composition in pigs was shown to change with meal frequency ( Allee et al, 1972 ; Le Naou et al, 2014 ).…”

“…However, body composition in pigs was shown to change with meal frequency ( Allee et al, 1972 ; Le Naou et al, 2014 ). As FI might be influenced by AA imbalance ( Yoshida et al, 1966 ; Benevenga et al, 1968 ), this study was set out to establish correlations between feeding behavior, protein deposition (PD), lipid deposition (LD), and plasma concentration of Thr in growing ( Remus et al, 2019a ) and finishing pigs ( Remus et al, 2019a ). Additionally, it was assessed potential differences in the feeding pattern of group-fed or individually fed pigs receiving different levels of Thr in the diet.…”