Candido Pomar

Agriculture and Agri-Food Canada | AAFC

Individual precision feeding (IPF) is a suitable tool to account for the nutritional requirement variability among pigs. It was previously reported that, within IPF, pigs require greater Thr:Lys than conventional group-phase feeding (GPF) pigs. It remains unknown if these differences in Thr:Lys requirements occur due to different growth rates (Gr)....

The immune response varies between pigs, as not all pigs have the same response to a stressor. This variation may exist between individuals due to body weight (BW) or body composition, which may impact the capacity for coping with an immune challenge (IC). Tryptophan (Trp), threonine (Thr), and methionine (Met) requirements might also play a consid...

Nitrogen and phosphorus excretion are major sources of environmental contamination in growing–finishing pig operations. Nutrient excretion can be reduced by feeding pigs daily-tailored diets to their estimated nutrient requirements using individual precision feeding (IPF) techniques. This study modeled and evaluated the environmental impact of movi...

Methionine (Met) is an essential amino acid that can be supplied in different chemical forms: DL-Met, L-Met, and OH-Met. This study aimed (i) to model and compare the utilization efficiency of Met for protein deposition (PD) from all sources and (ii) to determine the efficacy and efficiency of these three free Met sources in average daily gain (ADG...

This study investigated the ability of replacement gilts to adapt their calcium and phosphorus utilization and their kinetics in bone mineralization to compensate for modified intake of these nutrients by applying a novel Ca and P depletion and repletion strategy. A total of 24 gilts were fed according to a two-phase feeding program. In the first p...

This study aimed to measure protein deposition (PD) in pigs fed with daily tailored diets where either dietary lysine (Lys) or threonine (Thr) were provided at independent levels (ignoring an ideal ratio). A total of 95 growing pigs (35 kg body weight (BW)) with electronic ear tags granting them access to automatic feeders were randomly assigned to...

The efficiency of pig production using nutrients has increased over the years. Still, better efficiency of nutrient utilization can be achieved by feeding pigs with diets adjusted to their estimated requirements. An increase in nutrient efficiency of utilization represents economic gains while maximizing environmental performance. The objective of...

Pig and poultry production systems have reached high-performance levels over the last few decades. However, there is still room for improvement when it comes to their environmental sustainability. This issue is even more relevant due to the growing demand for food demand since this surplus food production needs to be met at an affordable cost with...

Esse estudo usa modelagem para simular o uso de nutrientes para suínos em crescimento e terminação recebendo dietas de baixa proteína ou em um sistema de alimentação de precisão individual.

Large variability in body composition is observed in pigs fed and raised in similar conditions. Part of this variation might be explained by the feeding behavior of pigs, given its effect on metabolic hormones associated with energy regulation and protein metabolism. The objective of this study was to elucidate this relationship by examining body c...

The use of radioactive isotopes to measure de novo lipogenesis in pigs has been well established. Different from radioactive isotopes, stable isotopes present little or no risk to human and animal subjects. Therefore, the objective of this study was to adapt the method of bolus injection of radioactive glucose ( 14C) to use 13C-labelled glucose to...

Describing the feeding behavior of pigs is difficult given the large day-to-day variations observed for a given animal. The objectives of this study were to create an index that integrates the information from several components of feeding behavior in order to account for intra-animal variation within a day and between days, and to evaluate the cap...

To determine amino acids (AA) requirements for pigs in precision feeding systems, it is important to understand the sources of variation in protein utilisation among pigs. It is possible that using fixed AA ratios to determine requirements limits protein deposition (PD) and contribute to this variation. This study aimed to measure PD in pigs fed wi...

This study aimed to evaluate the effect of individual precision feeding (IPF) compared to conventional 2 phase-feeding (2P) system in growing-finishing pigs receiving diets varying in crude protein (CP) content. Sixty crossbreed barrows were randomly distributed in a nested 2×2 factorial arrangement (IPF vs 2P and 2 CP levels, reduced CP (RCP) and...

Feeding behavior is an important aspect of pig husbandry, as it can affect protein deposition in pigs. A decrease in plasma threonine (Thr) levels may influence feed intake due to amino acid (AA) imbalance. We set out to study whether different Thr inclusion rates of 70%, 85%, 100%, 115% and 130% of the ideal Thr:lysine (Lys) ratio of 0.65 in two d...

Phosphorus ( P ) is an essential nutrient in livestock feed but can pollute waterways. In order for pig production to become less of a threat to the environment, excreta must contain as little P as possible or be efficiently used by plants. This must be achieved without decreasing the livestock performance. Phosphorus and calcium ( Ca ) deposition...

Pigs exposed to stressors can change their daily typical feeding intake pattern. The objective of this study was to develop a method for the early identification of deviations from an individual pig’s typical feeding patterns. In addition, a general approach was proposed to model feed intake and real-time individual nutrient requirements for pigs w...

Precision feeding using real-time models to estimate daily tailored diets can potentially increase nutrient utilization efficiency. To improve the amino acid requirements estimation for growing-finishing pigs, it is necessary to accurately estimate real-time body protein mass (BP).The aim of this study was to predict individual BP over time in orde...

Optimal amino acid ratios for pigs have been established for conventional phase feeding systems, but these ratios may differ for precision feeding systems. Our objective was to assess the impact of different dietary Thr inclusion levels (70%, 85%, 100%, 115%, or 130% of the estimated ideal 0.65 Thr:Lys ratio) on growth performance, plasma biochemic...

Precision feeding requires a mathematical model to estimate standardized ileal digestible (SID) lysine (Lys) requirements in real-time. However, this type of model requires constant calibration updates. The objective of this study was to review the calibration of the model used to estimate the real-time Lys requirements of individual growing-finish...

Significant differences in the estimation of amino acid requirements exist between the available factorial methods. This study aimed to compare current factorial models used to estimate the individual and population standardized ileal digestible (SID) lysine (Lys) requirements of growing pigs during a 26 day feeding phase. Individual daily feed int...

Abstract: This study aimed to estimate independently real-time lysine (Lys) and threonine (Thr) requirements in growing-finishing pigs. Ninety-five pigs were randomly assigned to treatments according to 2×5 factorial arrangement with 2 amino acids (AA; Lys, and Thr) and 5 levels of incorporation (60%, 80%, 100%, 120%, and 140% of the estimated requ...

This study focused on the relationship between feeding behaviour and the composition of the body gain in growing pigs. Feeding behaviour and body composition traits were calculated using individual information from 165 pigs during the last 28 days of the finishing period of 3 growing trials. A linear regression model describing the relationship bet...

This study aimed to predict real-time individual body protein mass (BP, kg), protein deposition rate (PD, g/d) and the proportion of PD in the body weight (BW, kg) gain (BWG, kg/d) over the growing-finishing period, as required for precision feeding.

Abstract: •Precision livestock farming (PLF) is proposed to the livestock industry as an essential tool to enhance sustainability and competitiveness. •Precision livestock feeding is part of PLF and can have a great impact in livestock profitability due the ability of feeding pigs with diets tailored daily to their nutrient requirements. •Precisi...

The objective of this study was to review the calibration of the model used to estimate real-time individual growing-finishing pigs Lys requirements. Two 28 d growth experiments were performed with 110 pigs distributed in a complete randomized design with growing (25 kg BW ± 2.1, n = 60; 10 pigs per treatment) or late-growing (68.1 kg BW ± 6, n = 6...

Implications • Utilization of precision feeding techniques in growing pig operations can significantly reduce production costs (>8%), protein and phosphorous intake (25%) and excretion (40%), and greenhouse gases emissions (6%) by increasing individual nutrient efficiency. • Precision feeding allows real-time off-farm monitoring and intelligent man...

There is a large variation in nutrient requirements among pigs, and, therefore, feeding pigs individually with diets tailored daily or in groups with a single feed may require different nutrients inclusion rates. The objective of this study was to evaluate the effect of the Met inclusion rate on growth performance, carcass quality, and nutrition he...

Background: There is large variation in amino acids requirements among pigs, so 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 studi...

This study aimed to compare growing pigs feeding behavior when fed with conventional group-phase feeding systems (CON) or fed individually with daily tailored diets (IND: individual precision feeding) under two ambient temperature conditions (TN: thermoneutral, 23°C; and HT: high temperature, 30°C). Forty-eight barrow pigs 44-kg (±0.98) BW were ass...

Accuracy, trueness, and precision of dual-energy X-ray absorptiometry (DXA) assessment of pig carcasses and primal cuts dissected tissues were evaluated using available region of interests (ROI) and Total Body and Small Animal software modes. Fat mass, lean mass, and bone mineral content (BMC) DXA values were compared to dissected tissue weights (f...

The precision of a dual-energy X-ray absorptiometry (DXA) device in terms of repeatability and reproducibility was evaluated on nine left half-carcasses from pigs with large variability in body weight and fat content. Repeatability was assessed by scanning each carcass 10 times sequentially in the same position. Reproducibility was assessed by scan...

Optimal AA ratios have been established for conventional group phase feeding (GPF) systems, but these ratios may differ in finishing pigs when fed with precision feeding systems (IPF). The aim of this study was to evaluate the response of different levels of threonine (Thr; 70, 85, 100, 115 and 130% of the 0.65 Thr: Lysine ideal protein ratio) in p...

This study was undertaken to evaluate the effect that switching from conventional to precision feeding systems during the growing-finishing phase would have on the potential environmental impact of Brazilian pig production. Standard life-cycle assessment procedures were used, with a cradle-to-farm gate boundary. The inputs and outputs of each inter...

The ability of birds to modify dietary phosphorus utilisation when fed with low-phosphorus and calcium (Ca) diets was studied using different sequences of dietary phosphorus and Ca restriction (depletion) and recovery (repletion) during the grower and the finisher phases. A total of 3600 Ross 708 broilers were randomly divided into 10 replicate pen...

The effect of a calcium (Ca) and phosphorus (P) depletion and repletion strategy was studied in four consecutive feeding phases of 28 days each. In all, 60 castrated male pigs (14±1.6 kg initial BW) received 60% (low (L) diet; depletion) or 100% (control (C) diet; repletion) of their Ca and digestible P requirements according to six feeding sequenc...

Pigs maintained in hot environments voluntarily reduce feed intake, and thus growth performance, to lower the heat dissipation burden. Feeding pigs with low-protein diets has been proposed to attenuate the negative effects of heat stress in pigs reared in hot climate areas. The aim of this study was to evaluate the performance and body composition...

Pigs fed individually with daily tailored diets (PF: precision feeding) may respond differently to amino acid (AA) supply compared to pigs fed under conventional group-phase feeding (GF) systems. The response of growing pigs in PF and GF systems fed with different levels of threonine (70%, 85%, 100%, 115%, and 130% of the ideal threonine-to-lysine...

Previous studies have demonstrated that precision feeding can significantly reduce nutrient intake and excretion in growing pigs reared in thermoneutral (TN) conditions. However, feeding pigs with low protein diets has been shown to attenuate the negative effects of heat stress in pigs reared in hot climate areas. The aim of this study was to evalu...

2nd place in the Graduate Poster Competition Abstract There is a large variation in nutrient requirements among pigs and therefore, feeding pigs individually with daily tailored diets, or in groups with a single feed, may require different levels of nutrients. The response to different levels of threonine (Thr): lysine (Lys) ratio (70, 85, 100, 115...

2nd Place in the Poster Graduate Competition Abstract Health challenges can affect production costs because they impair broiler performance. This metaanalysis was conducted to evaluate the performance responses of broiler chickens treated with feed additives (FA; prebiotic or probiotic or symbiotic), challenged by enteric bacteria. The database was...

There is a large variation in nutrient requirements among pigs, and therefore, individually feeding pigs with daily tailored diets may require different nutrient levels than when pigs are feed in groups with a single feed. Therefore, the response to different levels of Thr:Lys ratio (70, 85, 100, 115, and 130% of the 0.65 Thr:Lys ideal ratio) was s...

Guidelines have been developed in Quebec to maximize the benefits and minimize the risks associated with the application of livestock manure to agricultural soils. Within these guidelines, P content of manure has to be assessed and manure application adjusted to crop needs. However, the work required to obtain a representative sample of pig slurry...

The feeding behavior of growing-finishing pigs reared under precision feeding strategies was studied in 35 barrows and 35 females (average initial BW of 30.4 ± 2.2 kg) over 84 d. Five different feeding programs were evaluated, namely a conventional 3-phase program in which pigs were fed with a constant blend of diet A (high nutrient density) and di...

The feeding behavior of growing–finishing pigs reared under precision feeding strategies was studied in 35 barrows and 35 females (average initial BW of 30.4 ± 2.2 kg) over 84 d. Five different feeding programs were evaluated, namely a conventional 3-phase program in which pigs were fed with a constant blend of diet A (high nutrient density) and di...

This study was developed to assess the impact on performance, nutrient balance, serum parameters and feeding costs resulting from the switching of conventional to precision-feeding programs for growing–finishing pigs. A total of 70 pigs (30.4±2.2 kg BW) were used in a performance trial (84 days). The five treatments used in this experiment were a t...

The effect of Lys restriction followed by a repletion period on the performance of growing pigs was studied during 3 feeding phases, each lasting 28 d. A total of 47 castrated male pigs (G Performer 8.0 × Fertilis 25 pigs; Genetiporc Inc., Saint-Bernard, QC, Canada; initial BW of 26.7 ± 2.7 kg) were given each d 70% or 100% of their Lys requirement...

A better understanding of the fate of dietary P use by growing pigs will allow an optimization of P use and enhance sustainable practices. The optimization of P utilization is complicated by the multiple criteria, such as growth performance, bone mineralization, and manure P used for assessment of needs. Mathematical modeling is a useful tool to de...

The objective of this study was to compare actual factorial methods used to estimate phase-feeding growing pigs' lysine requirements with the method developed for precision feeding (PF) which provides individual pigs with daily tailored diets. Data from 36 high-performance pigs (25 kg initial BW, MSE= 2.23) were used in a 28-d trial. Observed indiv...

A better understanding of the fate of dietary P use by growing pigs will allow an optimization of P use and enhance sustainable practices. The optimization of P utilization is complicated by the multiple criteria, such as growth performance, bone mineralization, and manure P used for assessment of needs. Mathematical modeling is a useful tool to de...

The effect of Lys restriction followed by a repletion period on the performance of growing pigs was studied during 3 feeding phases, each lasting 28 d. A total of 47 castrated male pigs (G Performer 8.0 × Fertilis 25 pigs; Genetiporc Inc., Saint-Bernard, QC, Canada; initial BW of 26.7 ± 2.7 kg) were given each d 70% or 100% of their Lys requirement...

This study concerns feed composition and planning and is mainly focused in reducing feeding costs. We also estimate the excretion of nutrients that can be harmful to the environment when applied in excess but without trying to reduce them. The diets are formulated to satisfy or exceed the animal’s requirements, so their growth will not be affected....

Modelling is a useful tool for decision making in complex agro-industrial scenarios. The book contains a selection of the papers presented at the International Symposium of Modelling in Pig and Poultry Production 2013, and brings together the best and most recent academic work on modelling in the pig and poultry industries, with a particular emphas...

The implementation of precision feeding in growing-finishing facilities requires accurate estimates of the animals' nutrient requirements. The objectives of the current study was to validate a method for estimating the real-time individual standardized ileal digestible (SID) lysine (Lys) requirements of growing-finishing pigs and the ability of thi...

The aim of the present work was (1) to study the relationship between cross-sectional computed tomography (CT) images obtained in live growing pigs of different genotypes and dissection measurements and (2) to estimate carcass composition and cut composition from CT measurements. Sixty gilts from three genotypes (Duroc×(Landrace×Large White), Pietr...

Improving dietary P utilization without modifying pig performance is crucial for production sustainability. A feeding program comprising with three 28-day phases (20 to 40, 40 to 70 and 70 to 100 kg) was used to feed 72 pigs with an initial body weight of 20 kg. The ability of the pigs to modify the digestive and metabolic utilization of P when fed...

The impact of moving from conventional to precision feeding systems in growing-finishing pig operations on animal performance, nutrient utilization, and body and carcass composition was studied. Fifteen animals per treatment for a total of 60 pigs of 41.2 (SE = 0.5) kg of BW were used in a performance trial (84 d) with 4 treatments: a 3-phase feedi...

The effect of feeding pigs in a three-phase feeding (3PF) system or a daily-phase feeding (DPF) system on growth performance, body composition, and N and P excretions was studied on 8 pens of 10 pigs each. Feeds for the 3PF and DPF treatments were obtained by mixing two feeds, one with a high nutrient concentration and the other with a low nutrient...

L’effet d’une restriction en lysine suivie d’une période de réplétion sur les performances de porcs en croissance a été étudié pendant 3 phases d’alimentation de 28 jours chacune. Ainsi, 47 mâles castrés (poids vif initial de 26,7 ± 2,7 kg) ont reçu quotidiennement 70 ou 100 % de leurs besoins en lysine selon les séquences suivantes : 70‐70‐70, 70‐...

The objective of this study was to calibrate the mechanistic component of a mathematical model estimating in real‐time the individual lysine requirements of growing (from 25 to 55 kg body weight, BW) and finishing (from 70 to 100 kg BW) pigs. Four experimental diets were mixed daily at different proportions to provide each pig with a diet containin...

The objective of this study was to develop and evaluate a mathematical model used to estimate the daily amino acid requirements of individual growing-finishing pigs. The model includes empirical and mechanistic model components. The empirical component estimates daily feed intake (DFI), BW, and daily gain (DG) based on individual pig information co...

We look at the environmental impact of formulating diets for an animal production system, namely the case of growing pigs. The classic approach in animal production is to use a growth model based on the least-cost diet formulation. This optimal diet is generally established by linear programming. Such an approach can lead to adverse environmental e...