# On-farm validation of a feeding strategy improving nutritional and technological quality of meat from Duroc crossbred pigs and contributing to relocating feed resources

Isabelle Louveau, Justine Faure, Etienne Labussière, Bénédicte Lebret

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Isabelle Louveau, Justine Faure, Etienne Labussière, Bénédicte Lebret. On-farm validation of a feeding strategy improving nutritional and technological quality of meat from Duroc crossbred pigs and contributing to relocating feed resources. Animal - Open Space, 2026, 5, pp.100129. 10.1016/j.anopes.2026.100129. hal-05523024

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Research article

# On-farm validation of a feeding strategy improving nutritional and technological quality of meat from Duroc crossbred pigs and contributing to relocating feed resources

I. Louveau *, J. Faure, E. Labussière, B. Lebret

PEGASE, INRAE, Institut Agro, 35590 Saint Gilles, France

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## ARTICLE INFO

Article history:
Received 7 October 2025
Revised 6 January 2026
Accepted 16 January 2026

Handling editor: Marjeta Candek-Potokar

Keywords:
Faba bean
Fatty acids
Linseed
Meat quality
Pork

## ABSTRACT

There is an increasing demand from consumers and pork chain actors for farming practices improving simultaneously the intrinsic (e.g. sensory, nutritional, etc.) and the extrinsic (i.e. production-related: type and origin of feed resources, environmental impacts, etc.) quality attributes of pork. In this context, the present study was undertaken in a commercial farm to validate a feeding strategy designed to jointly improve intrinsic and extrinsic quality attributes of pork. The experiment included a total of 102 growing pigs (Danbred dams × Duroc sires) with females (n = 52) and castrated males (n = 50) over three replicates. At an average body weight (BW) of 32 kg, pigs were assigned to either a control (C) or an experimental diet based on "relocation of feed resources" (R). They were fed *ad libitum* one of the two diets according to a three-phase feeding programme until slaughter, when pigs achieved around 125 kg BW. The C diet was based on oilseed meals as a source of proteins and the R diet included extruded faba bean as the main source of proteins and extruded linseed as a source of n-3 polyunsaturated fatty acids (FAs). The average growth rate and slaughter BW tended to be higher (P < 0.1) in R than in C pigs, but hot carcass weight and lean meat content did not differ between the two feeding regimens. Ultimate pH in the *Longissimus* (LM) and ham (*Semimembranosus*, *Adductor*, *Gluteus medius* (GM) and *Gluteus superficialis*) muscles was higher (P < 0.01) in R than in C pigs. Drip loss in LM was lower (P < 0.001) in R than in C pigs. With respect to meat colour, L*, b*, C* and h° values measured 24 h after slaughter were lower (P < 0.01) in the LM and GM, indicating less light and redder meat (due to lower h°) from R compared with C pigs. Compared with the C diet, the R diet did not affect LM protein and lipid content but markedly reduced (P < 0.001) the n-6:n-3 and saturated:n-3 FA ratios in both LM and backfat. The current study confirms that in commercial conditions, feeding crossbred pigs with a faba bean-based diet enriched with extruded linseed is a favourable strategy to jointly improve the technological and nutritional properties of pork, while contributing to the relocation of feed resources.

© 2026 The Authors. Published by Elsevier B.V. on behalf of The animal Consortium. This is an open access article under the CC BY license ([http://creativecommons.org/licenses/by/4.0/](http://creativecommons.org/licenses/by/4.0/)).

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## Implications

Pork quality includes various attributes related to the product itself (carcass composition and conformation, and meat sensory,

technological and nutritional properties) and to pig farming conditions, including the geographical origin and nature of feed. The present study was undertaken to validate a feeding strategy designed to improve several quality attributes of pork on a commercial farm. Our study has demonstrated that feeding Danbred × Duroc crossbred pigs a faba bean-based diet enriched with extruded linseed is a favourable strategy to jointly improve the technological and nutritional properties of pork in commercial conditions, while contributing to the relocation of the protein resources.

<footnote>* Corresponding author.</footnote>

<footnote>E-mail address: isabelle.louveau@inrae.fr (I. Louveau).</footnote>
<table><caption>**Specifications table**</caption><thead><tr><th>Subject</th><th>Quality of Animal Products</th></tr></thead><tbody><tr><td>Type of data</td><td>Tables</td></tr><tr><td>How data were acquired</td><td>Weights of body and carcasses were recorded with electronic scales. Backfat and muscle thickness were determined at the carcass split with a ruler, and carcass lean meat percentage was determined directly with a calibrated ruler based on these measurements. Colour coordinates and pH of loin and ham muscles were determined using a Minolta CR-400 chromameter (Osaka, Japan) and a portable pH meter (HI98163, Hanna Instruments, Smithfields, RI, USA). The chemical composition of feeding formulae was assessed as described by Lebret et al. (2021). Experimental feeding formulae and muscle water contents were analysed according to the Association of Official Analytical Chemists. Nitrogen contents of muscle and feeding formulae were determined by the Dumas method (AOAC, 1990) with a FP828 (Leco, St Joseph, MI, USA). Protein contents were then based on the determined nitrogen content multiplied by 6.25 as the standard conversion factor. Total lipids were extracted from loin muscle, backfat, and feeding formulae according to the method of Folch et al. (1957) and were quantified gravimetrically. Fatty acid profiles of muscle, backfat and feeding formulae were determined after methylation with a gas chromatograph (Agilent Technologies 7890A, Santa Clara, CA, USA). Data analyses were performed using the Statistical Analysis System software (SAS Institute Inc., Cary, NC, USA).</td></tr><tr><td>Data format</td><td>Raw, processed and calculated data in Excel.</td></tr><tr><td>Parameters for data collection</td><td>Crossbred female and castrated male Duroc pigs (n = 102) were raised in a commercial farm. At around 32 kg, littermates were assigned to one of the two feeding regimens until slaughter at around 125 kg BW. The control diet was based on oilseed meal as a source of proteins, and the "relocation of resources" diet included extruded faba bean as the main source of proteins and extruded linseed as a source of n-3 polyunsaturated fatty acids.</td></tr><tr><td>Description of data collection</td><td>Data were collected by weighing individually living pigs before slaughter and postmortem carcasses in commercial facilities. After slaughter, meat quality traits were measured and tissue samples</td></tr></tbody></table>

<table><tr><td></td><td>(loin, ham muscles and adipose tissue) as well as feeding formulae were collected for biochemical analyses undertaken individually on all animals or feed samples.</td></tr><tr><td>Data source location</td><td>Institution: INRAE<br>City/Town/Region: Saint Gilles (35)<br>Country: France<br>Latitude and longitude: 48°8'37.332"N, 1°49'56.595"<br>GPS coordinates: 48.1452, -1.830114</td></tr><tr><td>Data accessibility</td><td>Repository name: https://entrepot.recherche.data.gouv.fr/<br>Data identification number: https://entrepot.recherche.data.gouv.fr/dataset.xhtml?persistentId=doi:10.57745/VAMCFZ</td></tr><tr><td>Related research article</td><td>Lebret, B., Lhuisset, S., Labussière, E., Louveau, I., 2023. Combining pig genetic and feeding strategies improves the sensory, nutritional and technological quality of pork in the context of relocation of feed resources. Meat Science, 2023 Mar;197:109074.<br>https://doi.org/10.1016/j.meatsci.2022.109074.</td></tr></table>

**Introduction**

Pork is the second most-consumed meat worldwide and the first meat consumed in Asia and Europe (OECD, 2025). Pork quality is an important issue in most countries, even though there are differences in the ranking of quality attributes among countries, consumers (according to their experience and motives), and circumstances of consumption (every day or 'extra') (Verbeke et al., 2010; Murphy et al., 2015; Lin-Schilstra et al., 2022). Quality of pork and pork products is multidimensional and can be defined by a set of intrinsic and extrinsic attributes (Lebret and Čandek-Potokar, 2022a). Intrinsic attributes include meat organoleptic, nutritional and technological properties (i.e. suitability for processing and storage). Extrinsic attributes refer to the way food is produced and include the ethical, cultural and environmental dimensions. They have become increasingly important in consumers' perceptions of pork and their purchasing decisions (Argemí-Armengol et al., 2019) while genetic selection has deeply modified carcass and meat composition towards more protein and less fat. The ambition of considering jointly the intrinsic and extrinsic quality attributes to better fit the expectations of consumers and pork chain stakeholders and thereby improve the sustainability of pork is a real challenge, and indeed corresponds to the concept of One Quality (Gagaoua et al., 2025a). This ambition is in line with the EU Commission strategy entitled the "Farm to Fork Strategy for a fair, healthy and environmentally friendly food system". Among others, this policy includes the objective of reducing dependency on critical feed materials (e.g. soya grown on deforested land) by fostering EU-grown plant proteins (EC, 2020).

Pig genotypes and feeding practices are major factors determining pork quality (Lebret and Čandek-Potokar, 2022a). Regarding genetics, a limited number of porcine breeds are used in the commercial pork industry. Among them, the Duroc breed used, either
as pure (Ciobanu et al., 2011) or as crossbred (Morales et al., 2013; Lebret et al., 2011), is favourable for sensory and technological quality in comparison with other selected breeds used in conventional production. Nevertheless, it is important to note that there is a difference in intramuscular fat content and therefore probably in sensory quality among Duroc lines (Schwob et al., 2020). Recently, we undertook a study under experimental conditions to evaluate the impact of the combination of genetic and feeding factors on several quality attributes of pork (Lebret et al., 2023). We demonstrated that the production of Duroc female crossbred pigs fed a faba bean-based diet as the main protein source and enriched with extruded linseed as a source of n-3 FA is a favourable strategy to improve simultaneously the sensory, nutritional and technological properties of pork. This strategy also contributes to improve the image attributes of pork by meeting the challenge of relocating protein resources to decrease feed material imports and thereby the dependence on third countries for animal feeding, and the environmental impacts of pork (Gagaoua et al., 2025b). A validation of this feeding strategy under commercial farming conditions and considering both castrated males and female Duroc crossbred pigs was needed before the transposition of this strategy on a larger scale. Therefore, the current study was undertaken to evaluate, on farm, the impact of two feeding strategies on several quality attributes of pork: a diet including faba bean (French origin) as a protein source and extruded linseed as source of n-3 FA, or a control diet based on oilseed meal (including imported soybean) as protein resources, both distributed according to a simplified multi-phase (three steps) feeding to female and castrated male crossbred Duroc pigs, on multiple quality attributes of pork.

## Material and methods

### Animals and experimental design

The experiment was conducted in a commercial farm (Le Cochon de Bretagne, 22190 Plérin, France) and included a total of 102 growing pigs with females (n = 52) and castrated males (n = 50) over three consecutive batches (n = 34 pigs/batch; i.e. 8 or 9 castrated males or females per dietary group/batch).

Animals originated from Danbred sows inseminated with semen from Duroc boars from Canadian origin (Genesis, 44150 Ancenis, France). Pigs were managed according to standard commercial pig farming procedures, with surgical castration performed during the first week of life. Pigs were issued from 34 litters (14, 10 and 10 litters for first, second and third batches, respectively). Within each batch, one to two (and three for one litter from batch two) pairs per litter were chosen at the end of the postweaning period on the basis of their sex and BW. Within a pair of littermates of the same sex, pigs were assigned to one of the two feeding regimens (Table 1). The following feeding strategy has been described and evaluated previously under experimental conditions (Lebret et al., 2023). Pigs from the control (C) treatment received a diet based on oilseed meals (imported soybean, rapeseed and dehulled sunflower) as protein resources. Pigs from the "relocation of resources" (R) treatment received a diet including extruded faba bean (French origin) as the main protein resource and extruded linseed (Valorex, France) as a source of n-3 polyunsaturated fatty acids (PUFAs) and contained 0.2% of antioxidants from plant origin (including vitamin E) to prevent PUFA oxidation. The high n-3 PUFA content of the R diet was in accordance with the specifications of the "Bleu Blanc Coeur" trademark for high nutritional quality. Within each feeding regimen, three formulae were successively distributed to pigs according to their growth phase: growing (from 31.6 to 63.5 kg BW), finishing (from 63.5 to 101.5 kg BW) and end-

finishing (from 101.5 kg until slaughter at around 125 kg BW). Within the growth phase, R and C diets were isoenergetic and provided the same amounts of SID amino acids. Diets were provided ad libitum and pigs had free access to water all along the experiment. Within batch, pigs of the two feeding regimens were housed in the same room during the whole experimental period, i.e. from 31.6 ± 3.22 kg BW until slaughter at 125.4 ± 11.95 kg BW, and castrated males and female pigs from the same feeding regimen were housed in the same pen (13.4 m²/pen; 0.79 m²/pig) on concrete floor (one pen per diet per replicate).

### Growth performance

Individual BWs of pigs were recorded at the start of each growth phase and the day before slaughter. Feed consumption during each phase was measured per pen, and average daily feed intake and feed conversion ratio were calculated per pen (n = 3 in each feeding regimen). Average daily gain was calculated per pig for each growth phase and over the whole experimental period.

### Slaughter and measurements of carcass and meat quality traits

All pigs in the same batch were slaughtered on the same day (19 September 2019, 12 December 2019, and 23 January 2020 for batches 1, 2 and 3, respectively). The day before slaughter, feed was removed at 0800 h. From 1000 h onwards, pigs were individually weighed, grouped within feeding treatment (i.e. with pigs from the same original pen without mixing with other pigs), placed on a roofed platform for around 2 h, and the two groups were transported (same truck) to a commercial slaughterhouse (Quintin Viandes, 22800 Quintin, France; distance: 70 km, around 1 h). Animals from the same feeding treatment were kept in lairage in the same pen and had free access to water. The next morning, pigs from each experimental treatment were alternately slaughtered by electrical head-stunning (300 V, 13 to 15 s duration) followed by jugular exsanguination in compliance with the current national regulations applied in slaughterhouses. Just after slaughter, the hot carcass (trimmed of digestive, reproductive, and respiratory tracts and of perirenal fat) was weighed. *Longissimus* muscle (LM) depth and backfat thickness (rind included) were measured at carcass split with a ruler according to the ZP method (minimal distance between vertebral channel and cranial end of *Gluteus medius* (GM) muscle for LM; minimal fat thickness over the GM for back-fat) and lean meat percentage was determined directly with a calibrated ruler based on these measurements (Font-i-Furnols et al., 2016).

After 24 h of chilling at 4 °C, the cold carcasses were weighed. The pH was measured at 24 h *postmortem* directly in the LM (between 1st and 2nd last ribs) and in ham *Semimembranosus* (SM), *Adductor* (AD), GM and *Gluteus superficialis* (GS) muscles with a portable pH meter equipped with a specific meat electrode (HI98163, Hanna Instruments, Smithfields, RI, USA). A transversal section of LM (10th dorsal vertebra level, 1.5 cm depth) was taken and bloomed for 15 min at 4 °C under artificial light before measurement of colour coordinates CIE L*: lightness, a*: redness, b*: yellowness, C*: saturation (chroma) and h*: hue (average values of three different determinations) using the Minolta CR-400 Chroma Meter (Osaka, Japan) with a D65 illuminant, a 1-cm diameter aperture and a 2° observer angle. Colour coordinates were also measured at one site of the GM and GS muscles, as described above. An additional slice of LM muscle (100 ± 10 g, consecutive to the previous one on the cranial side) was taken, weighed and kept at 4 °C in a plastic bag in hanging position for the determination of drip loss on day 4 *post-mortem* (Lebret et al., 2023).
<caption>**Table 1**</caption>

Composition and nutritional value of the experimental formulae used in the Control and R (relocation of feed resources) feeding regimen.

<table><thead><tr><th rowspan="2"></th><th colspan="3">Control</th><th colspan="3">R</th></tr><tr><th>G<sup>1</sup></th><th>F<sup>1</sup></th><th>E-F<sup>1</sup></th><th>G<sup>1</sup></th><th>F<sup>1</sup></th><th>E-F<sup>1</sup></th></tr></thead><tbody><tr><td colspan="7"><strong>Ingredients, % (as fed basis)</strong></td></tr><tr><td>Wheat</td><td>21.96</td><td>21.61</td><td>21.49</td><td>17.35</td><td>18.60</td><td>19.02</td></tr><tr><td>Maize</td><td>21.96</td><td>21.61</td><td>21.49</td><td>17.35</td><td>18.60</td><td>19.02</td></tr><tr><td>Barley</td><td>21.96</td><td>21.61</td><td>21.49</td><td>17.35</td><td>18.60</td><td>19.02</td></tr><tr><td>Wheat bran</td><td>3.17</td><td>8.86</td><td>10.76</td><td>3.13</td><td>8.41</td><td>10.18</td></tr><tr><td>Dehydrated beet pulp</td><td>1.59</td><td>4.43</td><td>5.38</td><td>1.56</td><td>4.21</td><td>5.09</td></tr><tr><td>Soybean meal 48</td><td>15.51</td><td>10.61</td><td>8.98</td><td>4.98</td><td>3.28</td><td>2.72</td></tr><tr><td>Rapeseed meal</td><td>3.39</td><td>2.23</td><td>1.85</td><td></td><td></td><td></td></tr><tr><td>Shelled sunflower meal</td><td>3.39</td><td>2.23</td><td>1.85</td><td></td><td></td><td></td></tr><tr><td>Extruded linseed + extruded faba bean</td><td></td><td></td><td></td><td>3.52</td><td>3.52</td><td>3.52</td></tr><tr><td>Faba bean<sup>2</sup></td><td></td><td></td><td></td><td>29.37</td><td>19.36</td><td>16.02</td></tr><tr><td>Cane molasses</td><td>2.00</td><td>2.00</td><td>2.00</td><td>2.00</td><td>2.00</td><td>2.00</td></tr><tr><td>Rapeseed oil</td><td></td><td></td><td></td><td></td><td>0.17</td><td>0.23</td></tr><tr><td>Sunflower oil</td><td>1.84</td><td>1.72</td><td>1.69</td><td></td><td></td><td></td></tr><tr><td>L-lysine HCl</td><td>0.40</td><td>0.36</td><td>0.34</td><td>0.23</td><td>0.24</td><td>0.25</td></tr><tr><td>Mineral-vitamin mix<sup>3</sup></td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td><td>0.50</td></tr><tr><td>Antioxidants (Sevefarm ®)<sup>4</sup></td><td></td><td></td><td></td><td>0.20</td><td>0.20</td><td>0.20</td></tr><tr><td colspan="7"><strong>Analysed chemical composition, %<sup>5</sup></strong></td></tr><tr><td>DM</td><td>87.5</td><td>87.4</td><td>87.4</td><td>88.2</td><td>87.8</td><td>87.7</td></tr><tr><td>CP</td><td>16.9</td><td>14.6</td><td>13.9</td><td>17.0</td><td>14.9</td><td>14.2</td></tr><tr><td>Crude fat</td><td>3.9</td><td>3.9</td><td>3.9</td><td>3.4</td><td>3.3</td><td>3.3</td></tr><tr><td>Crude fibre</td><td>4.5</td><td>4.8</td><td>5.0</td><td>5.5</td><td>5.5</td><td>5.5</td></tr><tr><td>Starch</td><td>39.6</td><td>40.4</td><td>40.5</td><td>41.2</td><td>41.4</td><td>41.5</td></tr><tr><td>Ash</td><td>5.4</td><td>5.3</td><td>5.3</td><td>5.5</td><td>5.3</td><td>5.2</td></tr><tr><td>Gross energy, MJ/kg</td><td>16.2</td><td>16.1</td><td>16.1</td><td>15.7</td><td>15.7</td><td>15.7</td></tr><tr><td colspan="7"><strong>Fatty acid (FA) composition, % of identified FA<sup>6</sup></strong></td></tr><tr><td>Saturated</td><td>13.9</td><td>14.3</td><td>14.4</td><td>13.9</td><td>14.0</td><td>14.0</td></tr><tr><td>Monounsaturated</td><td>22.3</td><td>21.7</td><td>21.6</td><td>19.5</td><td>21.7</td><td>22.3</td></tr><tr><td>Polyunsaturated (PUFA)</td><td>63.8</td><td>64.0</td><td>64.0</td><td>66.6</td><td>64.3</td><td>63.7</td></tr><tr><td>C18:3 n-3 (ALA<sup>7</sup>)</td><td>2.14</td><td>2.24</td><td>2.27</td><td>26.0</td><td>23.1</td><td>22.4</td></tr><tr><td>n-6:n-3 PUFA</td><td>28.8</td><td>27.6</td><td>27.2</td><td>1.56</td><td>1.78</td><td>1.85</td></tr><tr><td colspan="7"><strong>Calculated composition, %<sup>8</sup></strong></td></tr><tr><td>Digestible lysine, %</td><td>1.01</td><td>0.86</td><td>0.81</td><td>1.00</td><td>0.86</td><td>0.81</td></tr><tr><td>Net energy, MJ/kg</td><td>9.60</td><td>9.43</td><td>9.37</td><td>9.60</td><td>9.43</td><td>9.37</td></tr><tr><td>LysD/EN</td><td>1.00</td><td>0.86</td><td>0.81</td><td>1.00</td><td>0.86</td><td>0.81</td></tr><tr><td>Vitamin E</td><td>20</td><td>20</td><td>20</td><td>60</td><td>60</td><td>60</td></tr></tbody></table>

## Sampling and biochemical analyses

Representative samples of each experimental diet per feed fabrication (one fabrication of each diet at each batch) were analysed for DM, CP, crude fat, crude fibre, starch, ash and gross energy contents as described by Association of Official Analytical Chemists methods. On each carcass, on the day after slaughter, a complete cross-section of LM (1st-2nd last ribs) was taken, trimmed of external fat, minced and homogenised. A fraction was vacuum packaged and stored at -20 °C to determine intramuscular lipid (IMF) content and fatty acid (FA) composition; the rest was freeze-dried, then ground, before determination of protein and DM contents. A slice of SM muscle was also taken and prepared as described for LM for the determination of IMF, protein and DM contents. A sample of dorsal subcutaneous fat (back fat) was also taken at the last rib level, vacuum packaged and stored at -20 °C before extraction of lipids and analysis of the FA profile.

Muscle protein (=6.25 × nitrogen) and water contents were assessed from freeze-dried muscle samples. Nitrogen contents

were determined by the Dumas method (AOAC, 1990) with a FP828 (Leco, St Joseph, MI, USA). Water content was determined from freeze-drying, added to the residual water content of the freeze-dried material determined before and after an overnight oven-drying at 103 °C.

Protein and water contents were expressed as a percentage of fresh muscle, considering water loss of each muscle sample during freeze-drying. Lipid content was determined on muscle and adipose tissue samples kept at -20 °C. Total lipids of LM, SM and backfat were extracted from tissue samples by homogenisation in chloroform/methanol (2:1, v:v) according to the method of Folch et al. (1957) and were quantified gravimetrically after evaporation of the solvent under a nitrogen flow. For fatty acid analyses of the LM and backfat samples, extracted total lipids were stored in chloroform:methanol (2:1) containing 0.01% butylated hydroxytoluene (BHT) at -20 °C before FA methylation with boron trifluoride methanol, as described by Lebret et al. (2021). Analyses were performed with a gas chromatograph (Agilent Technologies 7890A, Santa Clara, CA, USA) equipped with an injector, a capillary column

<footnote n="1">¹ G: growing, F: finishing, E-F: end-finishing periods.</footnote>

<footnote n="2">² 90% faba beans + 10% soy beans extruded together.</footnote>

<footnote n="3">³ Contains 4 000 mg/kg vitamin E.</footnote>

<footnote n="4">⁴ Contains 20 000 mg/kg vitamin E, 50 000 mg/kg vitamin C, and aromatic substances.</footnote>

<footnote n="5">⁵ Analysed as described by Lebret et al. (2021) and expressed relative to fresh feed for DM, and to standardised DM of 88.0 % for all other components within each diet.</footnote>

<footnote n="6">⁶ Fatty acid (FA) profile of diets analysed by gas chromatography after chloroform-methanol extraction of lipids as described for the FA profile of intramuscular fat.</footnote>

<footnote n="7">⁷ ALA: Alpha linolenic acid.</footnote>

<footnote n="8">⁸ Calculated values as described by Furbeyre et al. (2020) and expressed on a fresh feed basis, except vitamin E that was calculated from its concentration in the ingredients of each diet.</footnote>
(30 m × 0.25 mm internal diameter) filled with a stationary phase containing 50% cyanopropylphenyl and 50% dimethylpolysiloxane (Agilent Technologies) and a flame ionisation detector (280 °C). The carrier gas was hydrogen. The column temperature was increased from 150 °C up to 220 °C (+4 °C/min) and reached a plateau after 10.5 min. Heptadecanoic acid (C17:0) was used as the internal standard. Retention times and peak areas were determined for all samples. The identities of the peaks were determined by comparing them to the retention times of standard FA methyl esters. For LM, the amount of each FA was calculated as a function of the internal standard (heptadecanoic acid, C17:0) and was expressed in mg per 100 g of muscle by considering the LM lipid content. For backfat, the FA composition was expressed as a percentage of identified FA.

## Statistical analyses

Statistical Analysis System software (version 9.4; SAS Institute, Cary, NC, USA) was used to analyse the data. The pig was considered as the statistical unit for traits measured individually. First, data were analysed by an analysis of variance (ANOVA, proc GLM) with feeding regimen, sex within feeding regimen, and batch as fixed effects to calculate residues. The normality of residues was checked (Kolmogorov-Smirnov, $P \ge 0.05$). For LM and SM lipid contents, as well as for the proportions of all individual FA in LM and in backfat, the data were log-transformed and tested again to assess the normality of their residues. Then, raw or log-transformed data were analysed by ANOVA (proc GLM) with feeding regimen, sex within feeding regimen and batch as fixed effects in the model. The interaction between feeding regimen and batch was not significant for any of the traits under study and was therefore not included in the model. Least-square means were calculated by feeding regimen and included in the tables.

## Results

### Growth performance

The feeding strategy tended to influence the growth performance of animals (Table 2). The average daily weight gain over the whole experimental period tended to be higher ($P = 0.061$) in

pigs receiving the R than in those receiving the C feeding regimen. However, differences in BW at slaughter between R and C pigs did not reach significance ($P = 0.10$). The average daily feed consumption estimated at the level of the pen during the three different growth periods was very close in the two feeding strategies (growing: 2.00 (R) vs 1.92 (C) kg feed/pig; finishing: 2.96 (R) vs 2.90 (C) kg feed/pig; end-finishing: 3.37 (R) vs 3.24 (C) kg feed/pig). Hot carcass weight, backfat thickness, muscle depth and lean meat content did not differ significantly between the two feeding regimens ($P > 0.10$).

### Meat quality indicators

The pH 24 h of the loin and the four ham muscles was higher ($P \le 0.001$) in R pigs than in C pigs (Table 3). This was associated with reduced ($P < 0.001$) drip loss in the LM from R pigs compared with C pigs. With respect to meat colour, significant differences were observed between the two feeding regimens. Lightness (L*) was lower ($P < 0.01$) in loin (LM) and ham (GM and GS) muscles from R compared with C pigs. The R pigs had also lower a* value ($P < 0.05$) in the LM and lower b* value ($P < 0.05$) in the LM, GM and GS muscles, leading to lower C* ($P < 0.01$) in the LM and GM and lower h° in the three muscles (LM, GM and GS), indicating a redder colour of the meat, compared with C pigs.

### Biochemical composition of muscles and adipose tissue

Water and protein concentrations were not affected by the feeding regimen in the SM muscle, but the R pigs tended to have lower water and slightly higher protein concentrations in the LM ($P < 0.10$) (Table 4). The feeding regimen did not influence the lipid content of the LL and SM muscles but strongly modified the fatty acid composition of the LM muscle (Table 4). Compared with C, the R diet greatly increased ($P < 0.001$) the concentration of all n-3 PUFA, with a strong increase in alpha-linolenic acid (ALA) and ecosapentaenoic acid (EPA) concentrations while the increase in docosahexaenoic acid (DHA) concentration was much more moderate. Conversely, the concentrations in n-6 PUFAs and particularly in linoleic acid (LA) were reduced ($P < 0.001$) in R pigs compared with C pigs, leading to a strong decrease ($P < 0.001$) in the n-6:n-3 and LA:ALA ratios. However, the concentrations of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty

<table><caption>**Table 2**
Growth performance and carcass traits of pigs according to feeding regimen: Control (C) or R (relocation of feed resources).</caption><thead><tr><th rowspan="2"></th><th colspan="2">Feeding regimen<fnref n="1" /></th><th rowspan="2">RMSE</th><th colspan="3">P-value<fnref n="2" /></th></tr><tr><th>C</th><th>R</th><th>F</th><th>S</th><th>B</th></tr></thead><tbody><tr><td>Number of animals</td><td>50</td><td>51</td><td></td><td></td><td></td><td></td></tr><tr><td>Growth performance</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Initial live weight (LW) (kg)</td><td>31.6</td><td>31.6</td><td>2.78</td><td>0.97</td><td>0.99</td><td>&lt;0.001</td></tr><tr><td>BW at end of growing (kg)</td><td>63.0</td><td>64.1</td><td>5.27</td><td>0.31</td><td>0.26</td><td>&lt;0.001</td></tr><tr><td>BW at end of finishing (kg)</td><td>100.6</td><td>102.5</td><td>6.87</td><td>0.18</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>BW at slaughter (kg)</td><td>124.0</td><td>126.8</td><td>8.60</td><td>0.10</td><td>0.003</td><td>&lt;0.001</td></tr><tr><td>Age at slaughter (d)</td><td>165</td><td>165</td><td>1.1</td><td>0.93</td><td>0.97</td><td>0.14</td></tr><tr><td>Average daily gain (ADG) (g)</td><td>997</td><td>1 028</td><td>81</td><td>0.061</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>ADG growing (g)</td><td>949</td><td>979</td><td>105</td><td>0.15</td><td>0.052</td><td>&lt;0.001</td></tr><tr><td>ADG finishing (g)</td><td>1 077</td><td>1 099</td><td>92</td><td>0.24</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>ADG end-finishing (g)</td><td>958</td><td>994</td><td>139</td><td>0.19</td><td>0.70</td><td>0.018</td></tr><tr><td>Carcass traits</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Hot weight (kg)</td><td>98.6</td><td>100.7</td><td>6.90</td><td>0.13</td><td>0.002</td><td>&lt;0.001</td></tr><tr><td>Muscle thickness (mm)<fnref n="3" /></td><td>76.5</td><td>76.7</td><td>4.48</td><td>0.78</td><td>0.23</td><td>&lt;0.001</td></tr><tr><td>Backfat thickness (mm)<fnref n="4" /></td><td>17.9</td><td>17.7</td><td>3.59</td><td>0.82</td><td>&lt;0.001</td><td>0.035</td></tr><tr><td>Lean meat content (%)<fnref n="5" /></td><td>59.2</td><td>59.3</td><td>1.84</td><td>0.82</td><td>&lt;0.001</td><td>0.40</td></tr></tbody></table>

<footnote n="1">¹ Least-square means calculated from raw data.</footnote>

<footnote n="2">² P-values of effects of feeding regimen (F), sex (S) within feeding regimen, and batch (B), and RMSE obtained from the ANOVA.</footnote>

<footnote n="3">³ Minimal distance between vertebral channel and cranial end of *gluteus medius* muscle.</footnote>

<footnote n="4">⁴ Minimal fat thickness over the *gluteus medius* muscle.</footnote>

<footnote n="5">⁵ Determined directly with a calibrated ruler (Font-i-Furnols et al., 2016).</footnote>
<table><caption>**Table 3**
Meat quality traits of the loin and ham muscles of pigs according to feeding regimen: Control (C) or R (relocation of feed resources).</caption><thead><tr><th rowspan="2"></th><th colspan="2">Feeding regimen<fnref n="1" /></th><th rowspan="2">RMSE</th><th colspan="3">P-value<fnref n="2" /></th></tr><tr><th>C</th><th>R</th><th>F</th><th>S</th><th>B</th></tr></thead><tbody><tr><td>Number of animals</td><td>50</td><td>51</td><td></td><td></td><td></td><td></td></tr><tr><td>Loin: <i>Longissimus</i> muscle</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>pH 24 h</td><td>5.57</td><td>5.66</td><td>0.10</td><td>&lt;0.001</td><td>0.069</td><td>&lt;0.001</td></tr><tr><td>Drip loss at 4 d p.m. (%)</td><td>5.20</td><td>3.63</td><td>1.29</td><td>&lt;0.001</td><td>0.002</td><td>&lt;0.001</td></tr><tr><td>Colour</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Lightness (L*)</td><td>52.6</td><td>50.9</td><td>2.67</td><td>0.003</td><td>0.11</td><td>&lt;0.001</td></tr><tr><td>Redness (a*)</td><td>6.55</td><td>6.05</td><td>0.98</td><td>0.012</td><td>0.64</td><td>&lt;0.001</td></tr><tr><td>Yellowness (b*)</td><td>5.84</td><td>5.13</td><td>0.93</td><td>&lt;0.001</td><td>0.20</td><td>0.001</td></tr><tr><td>Chroma (C*)</td><td>8.81</td><td>7.96</td><td>1.25</td><td>0.001</td><td>0.48</td><td>0.003</td></tr><tr><td>Hue angle (h°)</td><td>41.8</td><td>40.2</td><td>3.78</td><td>0.046</td><td>0.12</td><td>&lt;0.001</td></tr><tr><td>Ham muscles</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>pH 24 h <i>Semimembranosus</i></td><td>5.59</td><td>5.65</td><td>0.09</td><td>0.001</td><td>0.016</td><td>&lt;0.001</td></tr><tr><td>pH 24 h <i>Adductor</i></td><td>5.71</td><td>5.82</td><td>0.15</td><td>&lt;0.001</td><td>0.090</td><td>0.028</td></tr><tr><td>pH 24 h <i>Gluteus medius</i></td><td>5.56</td><td>5.62</td><td>0.08</td><td>&lt;0.001</td><td>0.082</td><td>&lt;0.001</td></tr><tr><td>pH 24 h <i>Gluteus superficialis</i></td><td>5.61</td><td>5.69</td><td>0.09</td><td>&lt;0.001</td><td>0.023</td><td>&lt;0.001</td></tr><tr><td>Colour <i>Gluteus medius</i></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Lightness (L*)</td><td>52.5</td><td>49.5</td><td>3.38</td><td>&lt;0.001</td><td>0.62</td><td>&lt;0.001</td></tr><tr><td>Redness (a*)</td><td>9.24</td><td>8.86</td><td>1.46</td><td>0.20</td><td>0.43</td><td>&lt;0.001</td></tr><tr><td>Yellowness (b*)</td><td>7.67</td><td>6.58</td><td>1.23</td><td>&lt;0.001</td><td>0.87</td><td>&lt;0.001</td></tr><tr><td>Chroma (C*)</td><td>12.0</td><td>11.0</td><td>1.76</td><td>0.007</td><td>0.58</td><td>&lt;0.001</td></tr><tr><td>Hue angle (h°)</td><td>39.5</td><td>36.5</td><td>3.77</td><td>&lt;0.001</td><td>0.41</td><td>0.014</td></tr><tr><td>Colour <i>Gluteus superficialis</i></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Lightness (L*)</td><td>50.1</td><td>48.5</td><td>2.91</td><td>0.007</td><td>0.15</td><td>0.003</td></tr><tr><td>Redness (a*)</td><td>10.1</td><td>10.1</td><td>1.44</td><td>0.88</td><td>0.046</td><td>&lt;0.001</td></tr><tr><td>Yellowness (b*)</td><td>7.43</td><td>6.93</td><td>1.19</td><td>0.038</td><td>0.024</td><td>&lt;0.001</td></tr><tr><td>Chroma (C*)</td><td>12.6</td><td>12.2</td><td>1.73</td><td>0.34</td><td>0.023</td><td>&lt;0.001</td></tr><tr><td>Hue angle (h°)</td><td>36.2</td><td>34.6</td><td>3.41</td><td>0.016</td><td>0.55</td><td>&lt;0.001</td></tr></tbody></table>

acids in the LM did not differ between R and C pigs. The effects of the feeding regimen on the composition of subcutaneous adipose tissue were very close to those found in the LM (Table 5). Tissue lipid content did not differ between the R and C pigs but the fatty acid profile was strongly modified with a marked increase (P < 0.001) in the proportion of n-3 PUFA and particularly in LA, and a decrease in the n-6 PUFA proportion (P = 0.011) in pigs receiving the R diet compared with pigs receiving the C diet. This also led to a strong reduction (P < 0.001) in the n-6:n-3 and LA: ALA ratios. The proportion of total PUFAs was slightly decreased (P = 0.011) in favour of those of MUFA in the subcutaneous fat of R compared with C pigs.

## Author's point of view

Associated with our previous findings (Lebret et al., 2023), the current study further shows that the production of Duroc crossbred pigs fed a faba bean-based diet enriched with extruded linseed and raised in commercial farming conditions with group housing, is a favourable strategy to jointly improve the nutritional properties of pork, while meeting the challenge of relocating the source of proteins to reduce dependence on countries from the global South for animal feeding. Feeding pigs with the R diets also improves the technological properties of meat, i.e. higher pH 24 h and lower drip loss, therefore leading to less light and redder meat (i.e., lower h° value; Lebret et al., 2015) in both loin and ham. The impact of the R feeding regimen on growth performance did not reach significance, in contrast to our previous findings (Lebret et al., 2023). In other studies, the dietary reduction of the n-6:n-3 ratio leads to an increase in average daily gain of pigs (Sun et al., 2020), whereas other studies failed to show such an effect (Nuernberg et al., 2005; Corino et al., 2008). This discrepancy

may be related to the investigation of different genotypes or the duration of distribution of the experimental diets. The lack of any effect of the feeding regimen on carcass traits is consistent with our previous observations (Lebret et al., 2023) and with other studies which examined the addition of linseed oil to pig feed (Kouba et al., 2003; Nuernberg et al., 2005; Corino et al., 2008) or the incorporation of extruded linseed into the feed of Piétrain crossbred pigs (Guillevic et al., 2009).

With respect to meat quality traits, the current study clearly shows an improvement in the technological quality of pork with the distribution of the R feeding regimen compared with the control. The lower lightness of the meat (loin and ham) of the R pigs compared with the C pigs is consistent with the higher ultimate pH of these muscles, these two characters being generally strongly correlated, and is associated with an improvement in the visual appearance of the meat (redder colour) (Gagaoua et al., 2023). The pH values of meat from R and C pigs were within the range of values considered “normal” for pork (5.50–5.80) (Prevolnik Polse et al., 2015). Within this range of values, an increase in pork pH is associated with higher processing yields (e.g.cooking). Therefore, one can conclude that meat from R pigs has a higher technological quality than that from C pigs (Lebret and Čandek-Potokar, 2022b).

In our previous observations (Lebret et al., 2023), differences in meat ultimate pH and colour of Duroc crossbred pigs fed the R vs C feeding regimen were in the same direction (less light and redder meat) but did not reach significance, except for hue angle of the GS muscle which was significantly lower (−3.9 pt, P ≤ 0.05) in R than C pigs. In this previous study, we reported a lower glycolytic potential (122 vs 147 µmole equivalent lactate/g, P ≤ 0.05) in the LM of Duroc crossbred pigs fed the R vs C feeding regimen, which could explain their higher ultimate pH and, consequently, lower meat

<footnote n="1">¹ Least-square means calculated from raw data.</footnote>

<footnote n="2">² P-values of effects of feeding regimen (F), sex (S) within feeding regimen, and batch (B), and RMSE obtained from the ANOVA.</footnote>
<caption>**Table 4**</caption>

Biochemical composition of the Longissimus and Semimembranosus muscles and fatty acid (FA) composition of the Longissimus muscle of pigs according to feeding regimen: Control (C) or R (relocation of feed resources).

<table><thead><tr><th rowspan="2"></th><th colspan="2">Feeding regimen<sup>1</sup></th><th rowspan="2">RMSE</th><th colspan="3">P-value<sup>2</sup></th></tr><tr><th>C</th><th>R</th><th>F</th><th>S</th><th>B</th></tr></thead><tbody><tr><td>Number of animals</td><td>50</td><td>51</td><td></td><td></td><td></td><td></td></tr><tr><td>Longissimus muscle</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Water (%)</td><td>74.8</td><td>74.6</td><td>0.48</td><td>0.078</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>Proteins (N × 6.25, %)</td><td>22.7</td><td>22.8</td><td>0.34</td><td>0.056</td><td>0.52</td><td>&lt;0.001</td></tr><tr><td>Lipids (%)</td><td>1.80</td><td>1.95</td><td>0.24</td><td>0.18</td><td>0.002</td><td>0.16</td></tr><tr><td>FA mg/100 g muscle</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>C10:0</td><td>1.97</td><td>2.20</td><td>0.32</td><td>0.13</td><td>0.011</td><td>0.002</td></tr><tr><td>C12:0</td><td>1.24</td><td>1.40</td><td>0.35</td><td>0.097</td><td>0.004</td><td>0.44</td></tr><tr><td>C14:0</td><td>17.50</td><td>20.42</td><td>0.34</td><td>0.048</td><td>&lt;0.001</td><td>0.10</td></tr><tr><td>C14:1</td><td>0.34</td><td>0.37</td><td>0.39</td><td>0.51</td><td>0.009</td><td>0.043</td></tr><tr><td>C15:0</td><td>0.76</td><td>0.76</td><td>0.19</td><td>0.64</td><td>0.39</td><td>&lt;0.001</td></tr><tr><td>C16:0</td><td>336.30</td><td>375.74</td><td>0.30</td><td>0.12</td><td>&lt;0.001</td><td>0.10</td></tr><tr><td>C16:1 n-9</td><td>3.59</td><td>3.65</td><td>0.22</td><td>0.94</td><td>0.92</td><td>0.94</td></tr><tr><td>C16:1 n-7</td><td>43.64</td><td>49.70</td><td>0.33</td><td>0.070</td><td>&lt;0.001</td><td>0.008</td></tr><tr><td>C18:0</td><td>173.95</td><td>193.24</td><td>0.30</td><td>0.13</td><td>&lt;0.001</td><td>0.35</td></tr><tr><td>C18:1 n-9</td><td>531.53</td><td>597.29</td><td>0.33</td><td>0.11</td><td>0.003</td><td>0.045</td></tr><tr><td>C18:1 n-7</td><td>51.88</td><td>58.61</td><td>0.31</td><td>0.069</td><td>0.002</td><td>0.032</td></tr><tr><td>C18:2 n-6 (LA)<sup>3</sup></td><td>163.09</td><td>143.77</td><td>0.16</td><td>&lt;0.001</td><td>0.82</td><td>0.54</td></tr><tr><td>C18:3 n-6</td><td>1.40</td><td>1.31</td><td>0.23</td><td>0.008</td><td>0.015</td><td>&lt;0.001</td></tr><tr><td>C18:3 n-3 (ALA)<sup>3</sup></td><td>4.28</td><td>21.11</td><td>0.26</td><td>&lt;0.001</td><td>0.16</td><td>&lt;0.001</td></tr><tr><td>C18:4 n-3</td><td>0.69</td><td>0.88</td><td>0.34</td><td>0.003</td><td>0.28</td><td>0.28</td></tr><tr><td>C20:0</td><td>2.88</td><td>3.47</td><td>0.40</td><td>0.066</td><td>0.003</td><td>0.002</td></tr><tr><td>C20:1 n-9</td><td>8.65</td><td>10.01</td><td>0.35</td><td>0.068</td><td>&lt;0.001</td><td>0.095</td></tr><tr><td>C20:2</td><td>5.20</td><td>4.48</td><td>0.24</td><td>0.001</td><td>0.44</td><td>0.085</td></tr><tr><td>C20:3 n-6</td><td>4.10</td><td>4.37</td><td>0.20</td><td>0.20</td><td>0.70</td><td>&lt;0.001</td></tr><tr><td>C20:4 n-6</td><td>34.64</td><td>24.17</td><td>0.14</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>C20:3 n-3</td><td>1.05</td><td>3.92</td><td>0.34</td><td>&lt;0.001</td><td>0.16</td><td>&lt;0.001</td></tr><tr><td>C20:4 n-3</td><td>0.35</td><td>0.67</td><td>0.55</td><td>&lt;0.001</td><td>0.85</td><td>&lt;0.001</td></tr><tr><td>C20:5 n-3 (EPA)<sup>3</sup></td><td>0.76</td><td>5.27</td><td>0.31</td><td>&lt;0.001</td><td>0.039</td><td>&lt;0.001</td></tr><tr><td>C22:0</td><td>0.43</td><td>0.59</td><td>0.53</td><td>0.29</td><td>0.89</td><td>0.003</td></tr><tr><td>C22:1 n-11</td><td>0.51</td><td>0.56</td><td>0.57</td><td>0.34</td><td>0.063</td><td>0.012</td></tr><tr><td>C22:4 n-6</td><td>6.05</td><td>2.80</td><td>0.23</td><td>&lt;0.001</td><td>0.83</td><td>&lt;0.001</td></tr><tr><td>C22:5 n-6</td><td>1.31</td><td>0.82</td><td>0.51</td><td>&lt;0.001</td><td>0.11</td><td>&lt;0.001</td></tr><tr><td>C22:5 n-3</td><td>4.29</td><td>10.05</td><td>0.19</td><td>&lt;0.001</td><td>0.22</td><td>&lt;0.001</td></tr><tr><td>C22:5</td><td>5.60</td><td>10.87</td><td>0.20</td><td>&lt;0.001</td><td>0.44</td><td>&lt;0.001</td></tr><tr><td>C22:6 n-3 (DHA)<sup>3</sup></td><td>1.36</td><td>1.65</td><td>0.33</td><td>0.003</td><td>0.002</td><td>&lt;0.001</td></tr><tr><td>SFA<sup>4</sup></td><td>535.02</td><td>597.81</td><td>0.30</td><td>0.12</td><td>&lt;0.001</td><td>0.18</td></tr><tr><td>MUFA<sup>4</sup></td><td>640.14</td><td>720.18</td><td>0.32</td><td>0.10</td><td>0.002</td><td>0.040</td></tr><tr><td>PUFA<sup>4</sup></td><td>228.60</td><td>225.27</td><td>0.15</td><td>0.49</td><td>0.99</td><td>0.028</td></tr><tr><td>n-6</td><td>210.60</td><td>177.24</td><td>0.15</td><td>&lt;0.001</td><td>0.99</td><td>0.054</td></tr><tr><td>n-3</td><td>12.79</td><td>43.54</td><td>0.21</td><td>&lt;0.001</td><td>0.87</td><td>&lt;0.001</td></tr><tr><td>n-6:n-3</td><td>17.33</td><td>4.11</td><td>0.12</td><td>&lt;0.001</td><td>0.69</td><td>&lt;0.001</td></tr><tr><td>C18:2 n-6: C18:3 n-3</td><td>40.37</td><td>7.02</td><td>0.15</td><td>&lt;0.001</td><td>0.035</td><td>&lt;0.001</td></tr><tr><td>SFA: n-3</td><td>44.23</td><td>13.61</td><td>0.23</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>Semimembranosus muscle</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Water (%)</td><td>74.4</td><td>74.3</td><td>0.76</td><td>0.37</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>Proteins (%)</td><td>21.8</td><td>21.8</td><td>0.41</td><td>0.83</td><td>0.026</td><td>0.008</td></tr><tr><td>Lipids (%)</td><td>2.82</td><td>3.09</td><td>0.31</td><td>0.28</td><td>&lt;0.001</td><td>&lt;0.001</td></tr></tbody></table>

lightness. This may be at least partly explained by the higher crude fibre content of the R vs C experimental formulae, as some literature data have shown that the incorporation of fibre into pigs' diet can lead to a reduction in muscle glycogen reserves (Li et al., 2015). By contrast, no differences were found on meat colour parameters and meat quality traits of Piétrain crossbred pigs fed the R compared with the C feeding strategy (Lebret et al., 2023). Our present results confirm our previous observations and, altogether, indicate that crossbred Duroc pigs may be more sensitive to the R feeding regimen than Piétrain crossbred pigs.

As well described previously (Wood et al., 2008; Corino et al., 2014; Huang et al., 2021) and demonstrated again in our previous

experiment (Lebret et al., 2023), the nature of dietary lipids strongly affects the FA composition and nutritional value of pork. The differences in lipid composition associated with the feeding regimen resulted in a decrease by a factor of 5.7 of the LA:ALA ratio in the meat from R pigs compared with C pigs. This led to a value of LA:ALA ratio below (in backfat) or very close (in LM) to the recommendations of ANSES (2011) with LA:ALA ≤ 5 and is also in agreement with the World Health Organization which strongly recommends the replacement of saturated fatty acids in the diet with polyunsaturated fatty acids (World Health Organization, 2023). The proportion of ALA (when expressed as a percentage of LM muscle FA, i.e. 1.4% in R pigs) and the n-6:n-3 and SFA:n-3

<footnote n="1">¹ Least-square means calculated from raw data.</footnote>

<footnote n="2">² P-values of effects of feeding regimen (F), sex (S) within feeding regimen, and batch (B), and RMSE obtained from the ANOVA applied to raw data for water and protein concentrations of both muscles, and to log values for lipid concentrations of both muscles and concentrations of all FA of *longissimus* muscle to fit a normal distribution.</footnote>

<footnote n="3">³ LA: linoleic acid. ALA: alpha-linolenic acid. EPA: ecosapentaenoic acid. DHA: docosahexaenoic acid;</footnote>

<footnote n="4">⁴ SFA: Saturated. MUFA: Monounsaturated. PUFA: Polyunsaturated FA.</footnote>
<caption>**Table 5**</caption>

Lipid content and fatty acid (FA) composition of backfat of pigs according to feeding regimen: Control (C) or R (relocation of feed resources).

<table><thead><tr><th rowspan="2"></th><th colspan="2">Feeding regimen<fnref n="1" /></th><th rowspan="2">RMSE</th><th colspan="3">P-value<fnref n="2" /></th></tr><tr><th>C</th><th>R</th><th>F</th><th>S</th><th>B</th></tr></thead><tbody><tr><td>Number of animals</td><td>50</td><td>51</td><td></td><td></td><td></td><td></td></tr><tr><td>Lipids (%)</td><td>71.04</td><td>72.29</td><td>3.93</td><td>0.11</td><td>0.004</td><td>&lt;0.001</td></tr><tr><td>FA composition (% of identified FA)</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>C10:0</td><td>0.08</td><td>0.08</td><td>0.11</td><td>0.60</td><td>0.20</td><td>0.14</td></tr><tr><td>C12:0</td><td>0.07</td><td>0.07</td><td>0.09</td><td>0.57</td><td>&lt;0.001</td><td>0.57</td></tr><tr><td>C14:0</td><td>1.16</td><td>1.16</td><td>0.07</td><td>0.95</td><td>&lt;0.001</td><td>0.013</td></tr><tr><td>C14:1</td><td>0.01</td><td>0.01</td><td>0.19</td><td>0.95</td><td>0.055</td><td>0.002</td></tr><tr><td>C15:0</td><td>0.05</td><td>0.05</td><td>0.14</td><td>0.003</td><td>0.10</td><td>&lt;0.001</td></tr><tr><td>C16:0</td><td>22.03</td><td>22.16</td><td>0.04</td><td>0.40</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>C16:1 n-9</td><td>0.38</td><td>0.35</td><td>0.14</td><td>0.003</td><td>&lt;0.001</td><td>0.012</td></tr><tr><td>C16:1 n-7</td><td>1.61</td><td>1.68</td><td>0.11</td><td>0.058</td><td>0.63</td><td>0.028</td></tr><tr><td>C18:0</td><td>12.55</td><td>12.83</td><td>0.08</td><td>0.12</td><td>&lt;0.001</td><td>0.21</td></tr><tr><td>C18:1 n-9</td><td>36.01</td><td>36.34</td><td>0.04</td><td>0.092</td><td>0.063</td><td>0.004</td></tr><tr><td>C18:1 n-7</td><td>1.99</td><td>2.16</td><td>0.07</td><td>&lt;0.001</td><td>0.016</td><td>0.001</td></tr><tr><td>C18:2 n-6 (LA)<fnref n="3" /></td><td>20.41</td><td>15.54</td><td>0.09</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>C18:3 n-6</td><td>0.06</td><td>0.04</td><td>0.33</td><td>&lt;0.001</td><td>0.065</td><td>0.11</td></tr><tr><td>C18:3 n-3 (ALA)<fnref n="3" /></td><td>0.90</td><td>4.46</td><td>0.09</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>C18:4 n-3</td><td>0.06</td><td>0.06</td><td>0.23</td><td>0.51</td><td>0.44</td><td>0.012</td></tr><tr><td>C20:0</td><td>0.22</td><td>0.24</td><td>0.14</td><td>0.003</td><td>0.12</td><td>0.069</td></tr><tr><td>C20:1 n-9</td><td>0.68</td><td>0.71</td><td>0.11</td><td>0.088</td><td>0.071</td><td>0.002</td></tr><tr><td>C20:2</td><td>0.83</td><td>0.66</td><td>0.09</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>C20:3 n-6</td><td>0.12</td><td>0.09</td><td>0.21</td><td>&lt;0.001</td><td>0.001</td><td>&lt;0.001</td></tr><tr><td>C20:3 n-3</td><td>0.12</td><td>0.61</td><td>0.13</td><td>&lt;0.001</td><td>0.004</td><td>&lt;0.001</td></tr><tr><td>C20:4 n-6</td><td>0.30</td><td>0.16</td><td>0.14</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>C20:4 n-3</td><td>0.01</td><td>0.04</td><td>0.41</td><td>&lt;0.001</td><td>0.82</td><td>&lt;0.001</td></tr><tr><td>C20:5 n-3 (EPA)<fnref n="3" /></td><td>0.02</td><td>0.07</td><td>0.33</td><td>&lt;0.001</td><td>0.028</td><td>&lt;0.001</td></tr><tr><td>C22:0</td><td>0.02</td><td>0.02</td><td>0.35</td><td>0.88</td><td>0.16</td><td>0.18</td></tr><tr><td>C22:1 n-11</td><td>0.01</td><td>0.02</td><td>0.39</td><td>0.034</td><td>0.41</td><td>0.016</td></tr><tr><td>C22:4 n-6</td><td>0.13</td><td>0.07</td><td>0.20</td><td>&lt;0.001</td><td>0.19</td><td>&lt;0.001</td></tr><tr><td>C22:5 n-6</td><td>0.04</td><td>0.04</td><td>0.70</td><td>0.45</td><td>0.88</td><td>0.002</td></tr><tr><td>C22:5 n-3</td><td>0.08</td><td>0.22</td><td>0.20</td><td>&lt;0.001</td><td>0.009</td><td>&lt;0.001</td></tr><tr><td>C22:6 n-3 (DHA)<fnref n="3" /></td><td>0.04</td><td>0.06</td><td>0.37</td><td>0.008</td><td>0.013</td><td>0.28</td></tr><tr><td>SFA<fnref n="4" /></td><td>36.19</td><td>36.62</td><td>0.04</td><td>0.15</td><td>&lt;0.001</td><td>0.096</td></tr><tr><td>MUFA<fnref n="4" /></td><td>40.70</td><td>41.27</td><td>0.04</td><td>0.064</td><td>0.079</td><td>0.002</td></tr><tr><td>PUFA<fnref n="4" /></td><td>23.11</td><td>22.12</td><td>0.08</td><td>0.011</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>n-6</td><td>21.06</td><td>15.95</td><td>0.09</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>n-3</td><td>1.22</td><td>5.51</td><td>0.08</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr><tr><td>n-6:n-3</td><td>17.32</td><td>2.89</td><td>0.06</td><td>&lt;0.001</td><td>0.050</td><td>0.032</td></tr><tr><td>C18:2 n-6: C18:3 n-3</td><td>21.42</td><td>3.46</td><td>0.05</td><td>&lt;0.001</td><td>0.014</td><td>0.092</td></tr><tr><td>SFA: n-3</td><td>30.21</td><td>6.73</td><td>0.10</td><td>&lt;0.001</td><td>&lt;0.001</td><td>&lt;0.001</td></tr></tbody></table>

ratios of the meat comply with the criteria of the “Bleu Blanc Coeur” specifications for pork of high nutritional value (target values: ALA ≥ 1.8% with tolerance ≥ 1.2%; n-6:n-3 ≤ 4 with tolerance ≤ 5, and SFA:n-3 ≤ 12 with tolerance ≤ 20) for products containing less than 7.5% fat, i.e. the LM muscle, and ALA ≥ 3.0% with tolerance ≥ 2.0%; n-6:n-3 ≤ 4 with tolerance ≤ 5, and SFA:n-3 ≤ 10 with tolerance ≤ 20) for products containing more than 7.5% fat, i.e. the subcutaneous fat).

In summary, the present work confirms that a R feeding regimen including extruded faba bean (French origin) as the main protein resource and extruded linseed as source of n-3 PUFA is an efficient way to jointly improve the nutritional value, technological properties and the societal image attributes of pork through relocation of protein resources, without impairing growth performance and carcass traits of castrated males and females crossbred pigs.

## Peer Review Summary

Peer Review Summary for this article (https://doi.org/10.1016/j.anopes.2026.100129) can be found at the foot of the online page, in Appendix A.

## Ethics approval

Animals were raised according to standard procedures for commercial farms. They were fed diets formulated to meet animal requirements and were transported to the commercial slaughterhouse and killed according to the routine procedure. Data and samples were collected as part of routine animal data collection in the slaughterhouse. Therefore, no extra animal discomfort was caused for the purpose of this study. With the use of animals in standard commercial conditions, the ethical review by the local Committee on Ethics in animal experimentation was not required.

## Declaration of generative AI and AI-assisted technologies in the writing process

During the preparation of this work the author(s) did not use any AI and AI-assisted technologies.

## Author ORCIDs

Isabelle Louveau: https://orcid.org/0000-0001-9684-6294.

Justine Faure: https://orcid.org/0000-0002-3008-2911.

<footnote n="1">¹ Least-square means calculated from raw data.</footnote>

<footnote n="2">² P-values of effects of feeding regimen (F), sex (S) within feeding regimen, and batch (B), and RMSE obtained from the ANOVA applied to raw data for lipid content and to log values for proportions of all FA to fit a normal distribution.</footnote>

<footnote n="3">³ LA: linoleic acid. ALA: alpha-linolenic acid. EPA: ecosapentaenoic acid. DHA: docosahexaenoic acid.</footnote>

<footnote n="4">⁴ SFA: Saturated. MUFA: Monounsaturated. PUFA: Polyunsaturated FA.</footnote>
**Etienne Labussière:** https://orcid.org/0000-0003-1945-0741.

**Bénédicte Lebreb:** https://orcid.org/0000-0001-5435-0389.

## Author contributions

**I Louveau:** Conceptualisation, Methodology, Validation, Investigation, Writing – original draft preparation, Writing-review and editing, Visualisation, Funding acquisition.

**J. Faure:** Conceptualisation, Investigation, Writing-review and editing.

**E. Labussière:** Conceptualisation, Methodology, Resources, Writing-review and editing.

**B. Lebreb:** Conceptualisation, Methodology, Validation, Formal analysis, Investigation, Resources, Data curation and Visualisation, Writing-re and editing, Supervision, Project administration, Funding acquisition.

All authors discussed the data, commented on the draft versions of the manuscript, and read, commented and approved the submitted version.

## Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

## Acknowledgements

The authors acknowledge "Le Cochon de Bretagne" (22190 Plérin, France) for the selection of the commercial farm, and J.C. Leroux and H. Guérin for breeding and taking care of the animals. They are grateful to the Valorex company (35210 Combourillé, France) for providing feed ingredients and more specifically to A. Minetto and M. Guillevic for their contribution to formulations and logistics issues of experimental formulae and logistics for implementing this on-farm experiment. They thank the staff of the INRAE experimental facility (UE 3P: Pig Physiology and Phenotyping Experimental Facility, https://doi.org/10.15454/1.5573932732039927E12) especially G. Guillemois and J. F. Rouaud (feed mill) and J. Liger (slaughterhouse) for their help in formulae preparations, and carcass measurements and sampling. They also thank the staff of commercial Quintin Viandes slaughterhouse (22800 Quintin, France) and Guyader pork processing company (22200 Saint-Agathon, France) for their help in carcass preparation and sampling. They are also grateful to INRAE PEGASE staff, especially S. Daré-Michelot, N. Bonhomme, S. Lhuisset, and F. Mayeur-Nickel for their excellent technical assistance. Finally, the authors are also grateful to the Valorial agri-food competitiveness cluster and all the partners of the ROC+ project for their contribution to setting up the project.

## Financial support statement

This work is part of the ROC+ project (2018-2021) and was supported by Région Bretagne and Rennes Métropole. The funding sources were not involved in the conduct of the research, interpretation of data, or writing of the manuscript.

## References

* Anses, 2011. Actualisation des apports nutritionnels conseillés pour les acides gras [updating of recommended nutrient intakes for fatty acids]. ANSES, Maisons-Alfort, France. Retrieved from: https://www.anses.fr/fr/system/files/NUT2006sa0359Ra.pdf; Accessed June 17, 2025.

* AOAC (1990) Official Methods of Analysis, 15th ed. Arlington, VA: AOAC. Google ScholarOpenURL query.

* Argemí-Armengol, I., Villalba, D., Ripoll, G., Teixeira, A., Alvarez-Rodriguez, J., 2019. Credence cues of pork are more important than consumers' culinary skills to boost their purchasing intention. Meat Science 154, 11-21.

* Ciobanu, C., Lonergan, S.M., Huff-Lonergan, E.J., 2011. Genetics of meat quality and carcass traits. In: Rothschild, M.F., Ruvinsky, A. (Eds.), The Genetics of the Pigs. 2nd ed. CAB Int, pp. 355-389.

* Corino, C., Musella, M., Mourot, J., 2008. Influence of extruded linseed on growth, carcass composition, and meat quality of slaughtered pigs at one hundred ten and one hundred sixty kilograms of liveweight. Journal of Animal Science 86, 1850-1860.

* Corino, C., Rossi, R., Cannata, S., Ratti, S., 2014. Effect of dietary linseed on the nutritional value and quality of pork and pork products: systematic review and meta-analysis. Meat Science 98, 679-688. https://doi.org/10.1016/j.meatsci.2014.06.041.

* European Commission, 2020. Communication from the Commission to the European parliament, the Council, the European Economic and Social Committee and the Committee of the Regions. A farm to fork strategy for a fair, healthy and environmentally-friendly food system COM/2020/381. Retrieved from: https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:52020DC0381. Accessed July 1, 2025.

* Folch, J., Lees, M., Sloane Stanley, G.H., 1957. A simple method for the isolation and purification of total lipids from animal tissues. Journal of Biological Chemistry 226, 497-509.

* Font-i-Furnols, M., Cande Potokar, M., Daumas, G., Gispert, M., Judas, M., Seynaeve, M., 2016. Comparison of national ZP equations for lean meat percentage assessment in SEUROP pig classification. Meat Science 113, 1-8. https://doi.org/10.1016/j.meatsci.2015.11.004.

* Furbeyre, H., Guillevic, M., Chesneau, G., Labussière, E., 2020. Effets du dépelliculage et de l'extrusion sur la valeur nutritionnelle de la graigne de féverole chez le porc en croissance. Journées Recherche Porcine, vol.52. Journées Recherche Porcine INRA-IFIP, Paris (France), pp. 87-92. Retrieved from: http://www.journees-recherche-porcine.com/texte/2020/alimentation/a04.pdf. Accessed June 17, 2025.

* Gagaoua, M., Surendranath, S.P., Purslow, P.P., Lebreb, B., 2023. The color of fresh pork: consumers expectations, underlying farm-to-fork factors, myoglobin chemistry and contribution of proteomics to decipher the biochemical mechanism. Meat Science 206, 1093540.

* Gagaoua, M., Gondret, F., Lebreb, B., 2025a. Towards a 'One quality' approach of pork: a perspective on the challenges and opportunities in the context of the farm-to-fork continuum - Invited review. Meat Science 226, 109834.

* Gagaoua, M., Auberger, J., Malnoë, C., Garcia-Launay, F., Lebreb, B., 2025b. Towards a one quality approach integrating intrinsic and extrinsic pork quality dimensions to foster the sustainability of pork production: a study combining pig genetics and feeding strategies. In: Proceedings of the 71st International Congress of Meat Science and Technology, 3-8 August 2025, Girona, Spain. In press.

* Guillevic, M., Kouba, M., Mourot, J., 2009. Effect of a linseed diet on lipid composition, lipid peroxidation and consumer evaluation of French fresh and cooked pork meats. Meat Science 81, 612-618.

* Huang, C., Chiba, L.I., Bergen, W.G., 2021. Bioavailability and metabolism of omega-3 polyunsaturated fatty acids in pigs and omega-3 polyunsaturated fatty acid-enriched pork: a review. Livestock Science 243, 104370.

* Kouba, M., Enser, M., Whittington, F.M., Nute, G.R., Wood, J.D., 2003. Effect of a high linolenic acid diet on lipogenic enzyme activities, fatty acid composition, and meat quality in the growing pig. Journal of Animal Science 81, 1967-1979.

* Lebreb, B., Cande Potokar, M., 2022a. Review: pork quality attributes from farm to fork. Part I. Carcass and fresh meat. Animal 16 (Supplement 1), 100402.

* Lebreb, B., Cande Potokar, M., 2022b. Review: pork quality attributes from farm to fork. Part II. Processed pork products. Animal 16 (Supplement 1), 100383.

* Lebreb, B., Prunier, A., Bonhomme, N., Fourny, A., Morméde, P., Dourmad, J.V., 2011. Physiological traits and meat quality of pigs as affected by genotype and housing system. Meat Science 88, 14-22.

* Lebreb, B., Prevolnik, Povše M., Cande Potokar, M., 2015. Muscle and fat colour. Farm Animal IMaging COST Action FA1102, pp. 33-44.

* Lebreb, B., Lenoir, H., Daré, S., Fonseca, A., Fève, K., Riquet, J., Mercat, M.J., 2021. Finishing season and feeding resources influence the quality of products from extensive-system Gascon pigs. Part 1: carcass traits and quality of fresh loin. Animal 15, 100240. https://doi.org/10.1016/j.animal.2021.100240.

* Lebreb, B., Lhuisset, S., Labussière, E., Louveau, I., 2023. Combining pig genetic and feeding strategies improves the sensory, nutritional and technological quality of pork in the context of relocation of feed resources. Meat Science 197, 109074.

* Li, Y., Li, J., Zhang, L., Yu, C., Lin, M., Gao, F., Zhou, G., Zhang, Y., Fan, Y., Nuldnali, L., 2015. Effects of dietary energy sources on post mortem glycolysis. Meat quality and muscle fibre type transformation of finishing pigs. PLoS One 10, e0131958.

* Lin-Schilstra, L., Backus, G., Snoek, H., Mörlein, D., 2022. Consumers' view on pork: Consumption motives and production preferences in ten European Union and four non-European Union countries. Meat Science 187, 108736.

* Morales, J.I., Serrano, M.P., Cámara, L., Berrocoso, J.D., López, J.P., Mateos, G.G., 2013. Growth performance and carcass quality of immunocastrated and surgically castrated pigs from crossbreds from Duroc and Pietrain sires. Journal of Animal Science 91, 3955-3964.

* Murphy, R.G., Howard, S.T., Woerner, D.R., Pendell, D.L., Dixon, C.L., Desimone, T.L., Green, M.D., Igo, J.L., Tatum, J.D., Belk, K.E., 2015. Definition, willingness-to-pay, and ranking of quality attributes of U.S. pork as defined by importers in Asia and Mexico. Journal of Animal Science 93, 433-441.
Nuernberg, K., Fischer, K., Nuernberg, G., Kuechenmeister, U., Klosowska, D., Eliminowska-Wenda, G., Fiedler, I., Ender, K., 2005. Effects of dietary olive and linseed oil on lipid composition, meat quality, sensory characteristics and muscle structure in pigs. *Meat Science* 70, 63–74.

OECD (2025). Meat Consumption. Retrieved on 1 July 2025 from: https://data.oecd.org/agroutput/meat-consumption.htm.

Prevolnik Povše, M., Čandek-Potokar, M., Gispert, M., Lebret, B., 2015. pH value and water-holding capacity. Farm Animal IMaging COST Action FA1102, pp. 22–32.

Schwob, S., Lebret, B., Louveau, I., 2020. Adiposité et génétique chez le porc: état des lieux et nouveaux enjeux pour la qualité des produits (Full text available in English). INRAE Productions Animales 33, 17–30.

Sun, H.Y., Yun, H.M., Kim, I.H., 2020. Effects of dietary n-6/n-3 polyunsaturated fatty acids ratio on growth performance, apparent digestibility, blood lipid profiles, fecal microbiota, and meat quality in finishing pigs. *Canadian Journal of Animal Science* 100, 272–281.

Verbeke, W., Perez-Cueto, F.J., Barcellos, M.D., Krystallis, A., Grunert, K.G., 2010. European citizen and consumer attitudes and preferences regarding beef and pork. *Meat Science* 84, 284–292.

Wood, J.D., Enser, M., Fisher, A.V., Nute, G.R., Sheard, P.R., Richardson, R.I., Hughes, S. I., Whittington, F.M., 2008. Fat deposition, fatty acid composition and meat quality: a review. *Meat Science* 78, 343–358.

World Health Organization, 2023. Saturated fatty acid and trans-fatty acid intake for adults and children: WHO guideline (Geneva, Switzerland).