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Enteric methane (CH4) emissions from ruminants have compelled a wide range of research initiatives to identify environmental abatement opportunities. However, although such mitigations can theoretically be attained with feed additives and feeding strategies, the limited empirical evidence on plant extracts used as feed additives does not support extensive or long-term reductions. Nevertheless, their strategic use (i.e. alone or combined in a simultaneous or consecutive use) may provide not only acceptable CH4 abatement levels, but also relevant effects on animal physiology and productivity. Condensed tannins (CT) represent a range of polyphenolic compounds of flavan-3-ol units present in some forage species that can also be added to prepared diets. Methods to determine CT, or their conjugated metabolites, are not simple. Although there are limitations and uncertainties about the methods to be applied, CT are thought to reduce CH4 production (1) indirectly by binding to the dietary fibre and/or reducing the rumen digestion and digestibility of the fibre and (2) directly by inhibiting the growth of rumen methanogens. On the basis of their role in livestock nutrition, CT influence the digestion of protein in the rumen because of their affinity for proteins (e.g. oxidative coupling and H bonding at neutral pH) that causes the CT-protein complex to be insoluble in the rumen; and dissociate in the abomasum at pH 2.5 to 3.0 for proteolysis and absorption in the small intestine. CT may also reduce gastro-intestinal parasite burdens and improve reproductive performance, foetal development, immune system response, hormone serum concentrations, wool production and lactation. The objectives of this paper are to discuss some of the beneficial and detrimental effects of CT on ruminant production systems and to develop a conceptual model to illustrate these metabolic relationships in terms of systemic physiology using earlier investigations with the CT-containing legume Lotus corniculatus. Our conceptual model indicated four complex and long-lasting relationships (digestive, toxicological, physiological and morphological) that can alter the normal biology of the animal. These relationships are interdependent, integrative, and sometimes, complementary to each other. This conceptual model can be used to develop mechanistic models to improve the understanding of the interaction between CT and the ruminants as well as to guide research initiatives of the impact of polyphenol-rich foods on human health.
In pasture-based seasonal calving systems, failure to become pregnant during the breeding season results in important economic losses as maximum profit is attained by minimising costs and increasing the proportion of grass in the diet of the lactating dairy cow. In the United States, dairy producers primarily strive to maximise production potential but are becoming increasingly aware of the economic consequences of sub-optimal cow fertility and survival. For this reason, interest in crossbreeding is emerging. The objective of this paper is to review the fertility and survival outcomes reported from recent research studies and data analyses in Ireland, New Zealand and the United States. Research conducted in Ireland during the early 2000s concluded that of three ‘alternative’ dairy breeds the Norwegian Red was most suited to seasonal grass-based production. A key finding was favourable fertility and survival. A follow-up study confirmed a fertility advantage with Norwegian Red×Holstein-Friesian compared with Holstein-Friesian: proportion pregnant to first service; +0.08 and in-calf after 6 weeks breeding; +0.11. Another study found higher fertility with Jersey crossbreds: pregnant to first service; +0.21, and in-calf after 6 weeks breeding; +0.19. Studies conducted in Northern Ireland also found superior fertility performance with Jersey crossbred cows offered low and moderate concentrate diets. In New Zealand, crossbred dairy cattle (primarily Jersey×Friesian) are achieving similar rates of genetic gain for farm profit as the purebred populations, but creating additional gain derived from economic heterosis. In the United States, analysis of commercial data from California showed higher first-service conception rates for Scandinavian Red×Holstein (+6 percentage units) and Montbeliarde×Holstein (+10 percentage units) compared with Holstein (23%). They also exhibited fewer days open and greater survival. At Penn State University, Brown Swiss×Holstein cows had 17 fewer days open than Holstein cows during first lactation, and numerically fewer in second (12 days) and third lactation (6 days). At the University of Minnesota, crossbred cows had 21 percentage units higher first-service conception rates, 41 fewer days open and 12 percentage units higher in-calf rates compared with pure Holstein cows. They also had greater survival to second (+13 percentage units), third (+24 percentage units), fourth (+25 percentage units) and fifth (+17 percentage units) lactation. The literature clearly illustrates favourable animal performance benefits from crossbreeding, using a range of modern breeds, and within the context of both grass-based and high-input confinement production environments. Economic analyses generally indicate profitable performance owing to lower replacement cost and higher herd productivity.
An experiment was conducted to examine whether increased CLA in milk of dairy cows fed fresh pasture compared with alfalfa and corn silages was because of ruminal or endogenous synthesis. Eight Holsteins were fed a total mixed ration using alfalfa and corn silages as the forage source in confinement or grazed in a replicated crossover design. The proportion of total fatty acids as CLA (primarily c9, t11-18:2) in g/100 g was 0.44 v. 0.28 in ruminal digesta, 0.89 v. 0.53 in omasal digesta and 0.71 v. 1.06 in milk during confinement feeding and grazing, respectively. Blood plasma CLA was 0.54 v. 1.05 mg/l for the two treatments, respectively. The increased concentration of CLA in milk with grazing likely resulted from increased synthesis through desaturation of t11-18:1 in the mammary gland.
Rangelands provide the main forage resource for livestock in many parts of the world, but maintaining long-term productivity and providing sufficient income for the rancher remains a challenge. One key issue is to maintain the rangeland in conditions where the rancher has the greatest possibility to adapt his/her management choices to a highly fluctuating and uncertain environment. In this study, we address management robustness and adaptability, which increase the resilience of a rangeland. After reviewing how the concept of resilience evolved in parallel to modelling views on rangelands, we present a dynamic model of rangelands to which we applied the mathematical framework of viability theory to quantify the management adaptability of the system in a stochastic environment. This quantification is based on an index that combines the robustness of the system to rainfall variability and the ability of the rancher to adjust his/her management through time. We evaluated the adaptability for four possible scenarios combining two rainfall regimes (high or low) with two herding strategies (grazers only or mixed herd). Results show that pure grazing is viable only for high-rainfall regimes, and that the use of mixed-feeder herds increases the adaptability of the management. The management is the most adaptive with mixed herds and in rangelands composed of an intermediate density of trees and grasses. In such situations, grass provides high quantities of biomass and woody plants ensure robustness to droughts. Beyond the implications for management, our results illustrate the relevance of viability theory for addressing the issue of robustness and adaptability in non-equilibrium environments.
Ruminant production systems have been facing the sustainability challenge, namely, how to maintain or even increase production while reducing their environmental footprint, and improving social acceptability. One currently discussed option is to encourage farmers to follow agroecological principles, that is, to take advantage of ecological processes to reduce inputs and farm wastes, while preserving natural resources, and using this diversity to increase system resilience. However, these principles need to be made more practical. Here, we present the procedure undertaken for the collaborative construction of an agroecological diagnostic grid for dairy systems with a focus on the mountain farming relying on the use of semi-natural grasslands. This diagnosis will necessarily rely on a multicriteria evaluation as agroecology is based on a series of complementary principles. It requires defining a set of criteria, based on practices to be recommended, that should be complied with to ensure agroecological production. We present how such agroecological criteria were identified and organized to form the architecture of an evaluation model. As a basis for this work, we used five agroecological principles already proposed for animal production systems. A group of five experts of mountain production systems and of their multicriteria evaluation was selected, with a second round of consultation with five additional experts. They first split up each principle into three to four generic sub-principles. For each principle, they listed three to eight categories of state variables on which the fulfilment of the principle should have a positive impact (e.g. main health disorders for the integrated health management principle). State variables are specific for a given production, for example, dairy farms. Crossing principles with state variables enabled experts to build five matrices, with 75 cells relevant for dairy systems. In each cell, criteria are specific to the local context, for example, mountain dairy systems in this study. Finally, we discuss the opportunities offered by our methodology, and the steps remaining for the construction of the evaluation model.
The impact of nutrition and energy reserves on the fertility of ruminants has been extensively described. However, the metabolic factors and the molecular mechanisms involved in the interactions between nutrition and ovarian function are still poorly understood. These factors could be hormonal (either reproductive and/or metabolic) and/or dietary and metabolic (glucose, amino acids and fatty acids). In this review, we briefly summarize the impact of those nutrients (fatty acids, glucose and amino acids) and metabolic hormones (insulin/IGF-I, growth hormone, T3/4, ghrelin, apelin and the adipokines (leptin, adiponectin and resistin)) implicated in the development of ovarian follicles, oocytes and embryos in ruminants. We then discuss the current hypotheses on the mechanisms of action of these factors on ovarian function. We particularly describe the role of some energy sensors including adenosine monophosphate-activated kinase and peroxisome proliferator-activated receptors in the ovarian cells.
Piglet survival is a major problem, especially during the first 3 days after birth. Piglets are born deficient of energy, but at the same time they have a very high energy requirement because of high physical activity, high need for thermoregulation (because of their lean body with low insulation) and high heat production in muscle tissues. To be able to survive, newborn piglets may rely upon three different sources of energy, namely, glycogen, colostrum and transient milk, which orchestrate to cover their energy requirements. Piglets are born with limited amounts of energy in glycogen depots in the liver and muscle tissues and these depots are sufficient for normal activity for ∼16 h. Intake and oxidation of fat and lactose from colostrum must supply sufficient amount of energy to cover at least another 18 h until transient milk becomes available in the sow udder ∼34 h after the first piglet is born. Selection for large litters during the last two decades has challenged piglets even further during the critical neonatal phase because the selection programs indirectly decreased birth weight of piglets and because increased litter size has increased the competition between littermates. Different attempts have been made to increase the short-term survival of piglets, that is, survival until day 3 of lactation, by focusing on improving transfer of vital maternal energy to the offspring, either in utero or via mammary secretions. Thus, the present review addresses how sow nutrition in late gestation may favor survival of newborn piglets by increasing glycogen depots, improving colostrum yield or colostrum composition, or by increasing production of transient milk.
The objectives were to evaluate quantitative animal-based measures of sow welfare (lameness, oral stereotypies and reactivity to humans) under commercial farm conditions, and to estimate the influence of housing, sow parity and stage of gestation on the outcome of these measures. Across 10 farms, 311 sows were used. Farms differed in terms of housing design (pen v. stall), space allowance, floor type in stalls (partially v. fully slatted), and feeding system in pens (floor v. trough). Lameness was assessed in terms of gait score, walking speed, stride length, stepping behaviour, response to a stand-up test and latency to lie down after feeding. The presence of oral stereotypies and saliva foam were recorded. Reactivity to humans was assessed by approach (attempt to touch the sow between the ears) and handling tests (exit of the stall for stall-housed sows, or isolation of the animal for pen-housed sows). Only stride length and walking speed were associated with lameness in stall-housed sows (P<0.05 and P<0.01). In stalls, the probability that a sow was lame when it presented a short stride length (<83 cm) or a low speed (<1 m/s) was high (69% and 72%, respectively), suggesting that these variables were good indicators of lameness, but were not sufficient to detect every lame sow in a herd (sensitivity of 0.39 and 0.71, respectively). The stage of gestation and parity also influenced measures of stride length and walking speed (P<0.05). Saliva foam around the mouth was associated with the presence of sham chewing and fixture biting (P<0.05). The probability that a sow presents sham chewing behaviour when saliva foam around her mouth was observed was moderate (63%) but was not sufficient to detect all sows with stereotypies (41%). A high discrimination index was obtained for behavioural measures (aggressions, escapes) and vocalisations during the approach test (stalls: 78.0 and 64.0; pens: 71.9 and 75.0, respectively), the number of interventions needed to make the sow exit the stall during the handling test for stall-housed sows (74.9), and attempts to escape during the handling test for pen-housed sows (96.9). These results suggest that these measures have a good power to discriminate between sows with low and high reactivity to humans. Finally, the outcome of several measures of lameness, stereotypies and reactivity to humans were influenced by the housing characteristics, sow parity and stage of gestation. Therefore, these factors should be considered to avoid misinterpretations of these measures in terms of welfare.
The present study evaluated the effects of a novel plant extract (PE) product (GrazixTM) on the performance and gut health of weaned piglets challenged with Escherichia coli. The PE was a standardised mixture of green tea leaves (Camellia sinensis) and pomegranate fruit (Punica granatum) obtained by using the LiveXtractTM process. A total of 144 piglets were weaned at 24 days and allocated to 8 for a 35-day experiment with a 2×2×2 factorial design comparing different treatments (water without product (CT) or 8 μl/kg per day PE in drinking water (PE)), feeding regimens (ad libitum (AD) or restricted (RE)) and oral E. coli challenges on day 9 (sham (−) or infected (+)). There were six pens per group with three piglets per pen. On day 35, 24 of the RE feeding piglets were slaughtered. It was found that PE supplementation increased the average daily gain (ADG) from day 28 to day 35 (P=0.03) and increased the gain to feed ratio (G : F) from day 7 to day 14 (P=0.02). RE feeding led to lower feed intake in piglets during the 1st week (P<0.01), 2nd week (P=0.06), 3rd week (P=0.05), and throughout the course of the overall study period (P=0.05). E. coli challenge decreased the ADG and G : F ratio from day 7 to day 14 (P=0.08 and <0.01, respectively) and increased the faecal score (higher values indicate more severe diarrhoea) on days 14, 21, 28 and 35 (P<0.01). PE supplementation decreased the faecal score in the challenged piglets during the 1st week post-challenge (P<0.01). E. coli challenge increased the faecal E. coli level on day 14 (P=0.03) and increased the Enterobacteriaceae level on day 35 (P<0.01). Reduced faecal E. coli was observed on days 14 and 35 (P=0.05 and 0.02, respectively), and reduced Enterobacteriaceae (P<0.01) was found on day 35 in the PE animals. RE feeding increased the faecal Lactobacillus, Enterobacteriaceae and E. coli levels on day 35 (P=0.02, <0.01 and <0.01, respectively). These results suggest that PE supplementation may improve the gut health status of post-weaning piglets and counteract some of the negative effects that occur when piglets are challenged with E. coli.
The objectives of this study were to analyze whether dry matter intake (DMI), water intake (WI) and BW were influenced by estrus. A second objective was to determine whether correlations exist among these traits in non-estrous days. Data collection included 34 Holstein-Friesian cows from the research farm ‘Haus Riswick’ of the Agricultural Chamber North Rhine-Westphalia, Germany. On an individual basis, daily DMI and daily WI were measured automatically by a scale in the feeding trough and a WI monitoring system, respectively. BW was determined by a walk-through scale fitted with two gates – one in front and one behind the scale floor. Data were analyzed around cow’s estrus with day 0 (the day of artificial insemination leading to conception). Means during the reference period, defined as days −3 to −1 and 1 to 3, were compared with the means during estrus (day 0). DMI, WI and BW were affected by estrus. Of all cows, 85.3% and 66.7% had reduced DMI and WI, respectively, on day 0 compared with the reference period. Lower BW was detected in 69.2% of all cows relative to the reference period. During the reference period, average DMI, WI and BW were 23.0, 86.6 and 654.8 kg. A minimum DMI of 20.4 kg and a minimum BW of 644.2 kg were detected on the day of estrus, whereas the minimum WI occurred on the day before estrus. After estrus, DMI, WI and BW returned to baseline values. Intake of concentrated feed did not seem to be influenced by estrus. Positive correlations existed between daily DMI and daily WI (r=0.63) as well as between cows’ daily BW and daily WI (r=0.23). The results warrant further investigations to determine whether monitoring of DMI, WI and BW may assist in predicting estrus.
Increase of fat cells (FCs) in adipose tissue is attributed to proliferation of preadipocytes or immature adipocytes in the early stage, as well as adipogenic differentiation in the later stage of adipose development. Although both events are involved in the FC increase, they are contrary to each other, because the former requires cell cycle activity, whereas the latter requires cell cycle withdrawal. Therefore, appropriate regulation of cell cycle inhibition is critical to adipogenesis. In order to explore the important cell cycle inhibitors and study their expression in adipogenesis, we adopted a strategy combining the Gene Expression Omnibus (GEO) database available on the NCBI website and the results of quantitative real-time PCR (qPCR) data in porcine adipose tissue. Three cell cycle inhibitors – cyclin G2 (CCNG2), cyclin-dependent kinase inhibitor 2C (CDKN2C) and peripheral myelin protein (PMP22) – were selected for study because they are relatively highly expressed in adipose tissue compared with muscle, heart, lung, liver and kidney in humans and mice based on two GEO DataSets (GDS596 and GDS3142). In the latter analysis, they were found to be more highly expressed in differentiating/ed preadipocytes than in undifferentiated preadipocytes in human and mice as shown respectively by GDS2366 and GDS2743. In addition, GDS2659 also suggested increasing expression of the three cell cycle inhibitors during differentiation of 3T3-L1 cells. Further study with qPCR in Landrace pigs did not confirm the high expression of these genes in adipose tissue compared with other tissues in market-age pigs, but confirmed higher expression of these genes in FCs than in the stromal vascular fraction, as well as increasing expression of these genes during in vitro adipogenic differentiation and in vivo development of adipose tissue. Moreover, the relatively high expression of CCNG2 in adipose tissue of market-age pigs and increasing expression during development of adipose tissue was also confirmed at the protein level by western blot analysis. Based on the analysis of the GEO DataSets and results of qPCR and Western blotting we conclude that all three cell cycle inhibitors may inhibit adipocyte proliferation, but promote adipocyte differentiation and hold a differentiated state by inducing and maintaining cell cycle inhibition. Therefore, their expression in adipose tissue is positively correlated with age and mature FC number. By regulating the expression of these genes, we may be able to control FC number, and, thus, reduce excessive fat tissue in animals and humans.
The use of molecular genetic information in the evaluation of livestock has become more common. This study looks at the efficacy of using such information to improve the genetic evaluation of a rare breed of dual-purpose cattle. Data were available in the form of pedigree information on the Gloucester cattle breed in the United Kingdom and recorded milk and beef performance on a small number of animals. In addition, molecular genetic information in the form of multi-marker, multiple regression results converted to a 1 to 10 score (Igenity scores) and 123 single nucleotide polymorphism (SNP) genotypes for 199 non-recorded animals were available. Appropriate mixed-animal models were explored for the recorded traits and these were used to calculate estimated breeding values (EBV), and their accuracies, for 6527 animals in the breed’s pedigree file. Various ways to improve the accuracy of these EBV were explored. This involved using multivariate BLUP analyses, genomic estimated breeding values (GEBV) and combining Igenity scores with recorded traits in a series of bivariate genetic analyses. Using the milk recording traits as an example, the accuracy of a number of traits could be improved using multivariate analyses by up to 14%, depending on the combination of traits used. The level of increase in accuracy largely corresponded to the absolute difference between the genetic and residual correlations between two traits, but this was not always symmetrical. The use of GEBV did not increase the accuracy of milk trait EBV owing to the low proportion of variance explained by the 101 SNPs used. Using Igenity scores in bivariate analyses with the recorded data was more successful in increasing EBV accuracy. The largest increases were found in genotyped animals with no recorded performance (e.g. a 58% increase in fat weight in milk); however, the size of the increase depended on the level of the genetic correlation between the recorded trait and the Igenity score for that trait. Lower levels of improvements in accuracy were seen in animals that were recoded but not genotyped, and ancestors which were neither genotyped nor recorded. This study demonstrated that it was possible to improve the accuracy of EBV estimation by including Igenity score information in genetic analyses but it also concluded that increasing the level of performance recording in the breed would be beneficial.
Surgical castration in pig husbandry is criticized for welfare reasons. Thus, it is necessary to evaluate alternative ways of rearing male pigs, such as entire or immunocastrated animals. Immunocastration is a vaccination directed against gonadotropin-releasing hormone (GnRH) to suppress the production of sexual hormones. This study aimed at investigating the effects of these two methods of castration in comparison with intact male pigs on blood T-lymphocyte subsets and function, the immunoglobulin (Ig) response to an influenza vaccine and health markers during sexual development. A total of 70 animals were allocated to three experimental groups: entire (E), surgically castrated at 5 to 6 days of age (SC), and immunized against GnRH at 3 and 4 months of age (IC). Blood samples were collected at 3, 4 and 5 months. At slaughter, global health status and body and spleen weights were measured. Results showed that SC male pigs had fewer blood lymphocytes than E pigs at 4 and 5 months (P<0.05), whereas IC pigs did not differ significantly from E pigs. The percentages of CD3+, CD3+CD4+ and CD3+CD8+ lymphocytes were not altered by treatment (P>0.1). Compared with E pigs, the SC pigs had a higher percentage of CD3+CD4+CD8+ cells at 4 months, whereas the IC pigs had a higher percentage at 5 months (P<0.05). Regarding γδT cells, SC pigs had a lower percentage than E pigs at 4 and 5 months (P<0.05), whereas IC pigs did not differ significantly from E pigs at any age. However, there were no consequences on T-lymphocyte proliferation and total IgG or anti-influenza Ig. At slaughter, relative spleen weight was decreased in IC pigs, whereas pneumonia score was decreased in SC pigs relatively to E pigs. Overall, no clear functional consequences of either method on commercial pig immune abilities were demonstrated, but more investigations are required to ascertain this conclusion.
Welfare concerns for intensive beef production have often been raised, but on-farm welfare assessment studies are rare. The aim of this study was to apply the Welfare Quality® (WQ) welfare assessment system for fattening cattle on beef bull farms to evaluate the state of welfare at the level of WQ measures and of aggregated scores, as well as overall classification. In addition, the purpose was to evaluate two ways of providing feedback information to the farmers with regard to possible welfare improvements on the farms. The study was conducted in Austria, Germany and Italy on a total of 63 beef bull farms with deep litter or cubicle-housing systems. Assessments were carried out 3 times (1 month and 7 months apart from the initial visit). In every country, farmers were assigned to two treatment groups (feedback from initial visit as written report, F, written feedback plus oral advice, FA) and a control group (C), which did not receive any feedback. At the criterion level, the highest average welfare scores were obtained from ‘Absence of prolonged hunger’ (94/100 points) followed by ‘Absence of pain induced by management procedures’ (88/100) and ‘Comfort around resting’ (77/100). Most welfare concerns related to the criteria ‘Absence of disease’ (40/100), ‘Expression of social behaviour’ (44/100) and ‘Positive emotional state’ (48/100), thus indicating room for improvements. Two-thirds of the farms achieved the ‘Enhanced’ level, about one-third was judged ‘Acceptable’ and only one farm ‘Excellent’. After 6 months of monitoring period, there was no significant welfare improvement in both the treatment groups as compared with the control group. Reasons for the lack of effect may mainly be seen in the short monitoring period and a lack of external incentives. In conclusion, the WQ assessment system revealed areas for improvement, but longer term studies and investigations on alternative ways of transferring outcomes from on-farm welfare assessments to farmers should be carried out in future.
The objective of this study was to identify detailed fertility traits in dairy and beef cattle from transrectal ultrasonography records and quantify the associated risk factors. Data were available on 148 947 ultrasound observations of the reproductive tract from 75 949 cows in 843 Irish dairy and beef herds between March 2008 and October 2012. Traits generated included (1) cycling at time of examination, (2) cystic structures, (3) early ovulation, (4) embryo death and (5) uterine score; the latter was measured on a scale of 1 (good) to 4 (poor) characterising the tone of the uterine wall and fluid present in the uterus. After editing, 72 773 records from 44 415 dairy and beef cows in 643 herds remained. Factors associated with the logit of the probability of a positive outcome for each of the binary fertility traits were determined using generalised estimating equations; linear mixed model analysis was used for the analysis of uterine score. The prevalence of cycling, cystic structures, early ovulation and embryo death was 84.75%, 3.87%, 7.47% and 3.84%, respectively. The occurrence of the uterine heath score of 1, 2, 3 and 4 was 70.63%, 19.75%, 8.36% and 1.26%, respectively. Cows in beef herds had a 0.51 odds (95% CI=0.41 to 0.63, P<0.001) of cycling at the time of examination compared with cows in dairy herds; stage of lactation at the time of examination was the same in both herd types. Furthermore, cows in dairy herds had an inferior uterine score (indicating poorer tone and a greater quantity of uterine fluid present) compared with cows in beef herds. The likelihood of cycling at the time of examination increased with parity and stage of lactation, but was reduced in cows that had experienced dystocia in the previous calving. The presence of cystic structures on the ovaries increased with parity and stage of lactation. The likelihood of embryo/foetal death increased with parity and stage of lactation. Dystocia was not associated with the presence of cystic structures or embryo death. Uterine score improved with parity and stage of lactation, while cows that experienced dystocia in the previous calving had an inferior uterine score. Heterosis was the only factor associated with increased likelihood of early ovulation. The fertility traits identified, and the associated risk factors, provide useful information on the reproductive status of dairy and beef cows.
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 concentration. The DPF pigs tended (P=0.08) to consume more feed (+3.7%) than the 3PF pigs, but only during the first feeding phase. The DPF pigs consumed 7.3% less protein (P<0.01) but a similar amount of total P. For the whole growing period, the DPF pigs tended (P=0.08) to gain more weight (+2.4%) than the 3PF pigs, mainly because of faster growth (P=0.02) during the first feeding period. At the end of the experiment, total body protein mass was similar in the two treatment groups, but the DPF pigs had 8% more body lipids (P=0.04) than the 3PF pigs. Daily multiphase feeding reduced N excretion by 12% (P<0.01) but did not significantly reduce P excretion. In addition, feed costs, nutrient intake and nutrient excretion under the two feeding strategies were simulated and compared after different approaches were used to formulate complete feeds for each phase of the 3PF system, as well as the two feeds used in the DPF program. Simulated feed intake and growth was similar to those observed in the animal experiment. In comparison with the simulated 3PF system, the feed cost for the DPF pigs was reduced by 1.0%, the simulated N and P intakes were reduced by 7.3% and 4.4%, respectively, and the expected N and P excretions were reduced by 12.6% and 6.6%, respectively. The concomitant adjustment of the dietary concentration of nutrients to match the evaluated requirements of pig populations can be an efficient approach to significantly reduce feeding costs and N and P excretions in pig production systems.