Carcass Composition and Physicochemical Characteristics of Meat from Pork Chains Based on Native and Hybrid Pigs

: The purpose of the research was to investigate the carcass composition, meat quality and chemical composition of pigs from two pork chains for the production of traditional dry/cured products in Croatia. The trial involved 24 Black Slavonian barrows reared outdoors (NAT chain) and 24 PIC hybrid barrows kept under industrial conditions (INT chain); all animals were raised to 160 kg of live weight. After slaughter, carcass and meat quality traits were measured and samples for chemical composition were taken. After that, a full dissection of the carcasses was performed. The pigs from the INT pork chain had leaner carcasses, higher bone percentages, and lower fatness levels than the NAT carcasses. Pigs from the NAT chain exhibited a more desirable meat quality. No differences were found in moisture, and samples from the INT chain exhibited higher collagen and protein percentage. Muscles from the NAT chain had higher IMF and MUFA levels, and the SFA content was lower than in INT pork. Despite the superior carcass traits of the pigs from the INT chain, pigs from the NAT chain demonstrated better suitability for the production of dry/cured products.


Introduction
Most of the pork today comes from modern breeds or hybrids exhibiting certain advantages over native breeds, such as a high prolificacy, very fast growth and increased lean meat percentages in the carcasses. On the other hand, those animals are extremely sensitive to microclimatic condition changes and are often prone to stress and diseases. For these reasons, the production of such pigs requires very strict management and housing conditions. Additionally, their meat is often characterized by unsatisfactory quality traits such as high drip loss, colour deterioration and reduced intramuscular fat content (IMF), thus making it less suitable for processing into products [1], especially high-quality those of high quality or labelled with protected denomination of origin (PDO) or protected geographic indication (PGI).
It is a growing trend that consumers today demand tasty, locally produced food originating from environment-and animal-friendly production systems [2]. Over 80 pork production systems in European countries have been recognized, with approximately half of them considered conventional and half considered alternative based on claims on improved eating quality, animal welfare, environmental impact, local impact, etc. [3]. Claims of higher meat quality rely on the assumption that it can be improved by choosing the appropriate breed, rearing system, and/or feeding strategy combined into a specific quality pork chain.
Some pork chains are based on local breeds kept in extensive rearing conditions, and in some chains, conventional hybrids are reared in an intensive production system

Animals, Production Chains, and Slaughter Procedure
The experimental protocol was approved by the Bioethics Committee of the Faculty of Agrobiotechnical Sciences Osijek (602-04/21-01/07), and all procedures were performed in accordance with the Croatian Animal Welfare Act and other legal acts regulating animal husbandry and welfare.
Animals used in the present study originated from two production chains: one based on a Croatian native pig breed (NAT) and the other based on hybrid pigs reared in a prolonged fattening period (INT). The NAT pork chain sample consisted of Black Slavonian pig barrows (n = 24) and the INT chain Pietrain involved PIC (Pig Improvement Company; P337 (Pietrain × Duroc × Pietrain) × Camborough 23) (n = 24) hybrids. The animals from Processes 2022, 10, 370 3 of 13 both pork chains were littermates originating from six litters farrowed within two weeks. The animals were randomly assigned to each of the treatments, and the treatments were performed in duplicate.
The NAT pork chain is a local specific system for Black Slavonian pigs kept in pastures that allow 300 m 2 space per pig with 80 m 2 of the canopy to protect animals from uncomfortable climate conditions. Feeding was based on alfalfa ad libitum, with the daily addition of 2 kg whole grains.
The INT pork chain sample consisted of PIC hybrid pigs that were reared in an intensive indoor production system with ad libitum access to food and water in a prolonged fattening period. The fatteners were group-penned. During the experiment, pigs were fed five different commercial diets consisting of 13.58 MJ/ME and 17.36 g/kg of crude protein (CP) to 30 kg of live weight (LW), 13.50 MJ/ME and 16.00 g/kg of CP from 30 to 55 kg LW, 13.05 MJ/ME and 14.00 g/kg of CP from 55 to 85 kg LW, 13.00 MJ/ME and 13.99 g/kg of CP from 85 to 115 kg LW, and 12.81 MJ/ME and 13.01 g/kg of CP from 115 to 160 kg slaughter weight.
The composition of the supplemented feed for BS fatteners and diet fed from 115 kg to approximately 160 kg LW for PIC porkers is presented in Table 1. After reaching the designated LW of 160 ± 3 kg (at the approximate age of 2 years for pigs from the NAT chain and 7 months for pigs from the INT chain), the animals were transported to a near abattoir where they were exsanguinated following stunning with CO 2 . To enhance pig welfare, food safety and meat quality, animals were fasted for 18 h before slaughter.

Carcass Traits
After 24 h of cooling, carcass length (distance from the cranial edge of Os pubis to the cranial edge of the 1st rib) and ham length (from the anterior edge of the Symphysis ossis pubis to the hock joint), together with the ham circumference at its widest point, were measured. The ham index was determined as the ratio between ham length and ham circumference. Muscle thickness and fat thickness were determined using the "Two points (TP)" method approved in Croatia [19]. At the slaughterhouse after 24 h of cooling, the left sides of the pig carcasses were dissected according to the modified "Kulmbach" method [20], as schematically presented in Figure 1. The main parts were then further dissected into muscle tissue, fatty tissue (intermuscular and subcutaneous with skin) and bone, and then they were weighed. The weights of the parts (dissected and non-dissected) were measured using a Mettler-Toledo Viper SW 15 scale (Mettler-Toledo, Greifensee, Switzerland).

Carcass Traits
After 24 h of cooling, carcass length (distance from the cranial edge of Os pubis to the cranial edge of the 1st rib) and ham length (from the anterior edge of the Symphysis ossis pubis to the hock joint), together with the ham circumference at its widest point, were measured. The ham index was determined as the ratio between ham length and ham circumference. Muscle thickness and fat thickness were determined using the "Two points (TP)" method approved in Croatia [19].
At the slaughterhouse after 24 h of cooling, the left sides of the pig carcasses were dissected according to the modified "Kulmbach" method [20], as schematically presented in Figure 1. The main parts were then further dissected into muscle tissue, fatty tissue (intermuscular and subcutaneous with skin) and bone, and then they were weighed. The weights of the parts (dissected and non-dissected) were measured using a Mettler-Toledo Viper SW 15 scale (Mettler-Toledo, Greifensee, Switzerland).

Meat Quality Traits
Post mortem measurements of muscle pH were determined at longissimus thoracis et lumborum (LTL) muscle 45 min (pH45) and 24 h (pH24) after slaughter with an HI 99613 portable meat pH meter (Hanna Instruments, Woonsocket, RI, USA). Drip was measured using the EZ-DripLoss method [21] after 48 h of cooling at 4 °C. The Colour of the LTL samples (the average of three measurements) was evaluated after 20 min of blooming using a Minolta CR-410 colourimeter (Minolta Camera Co. Ltd., Osaka, Japan) with a D65 light source and 10-degree standard observer. Light reflectance scores for CIE L*a*b*, chroma (saturation; C*) and hue angle (h°) were determined.

Chemical Composition and Fatty Acids
The chemical composition of the samples was determined using standard analytical methods (moisture, [22]; total fat, [23]; nitrogen, [24]). The fatty acid composition of subcutaneous fat and IMF was determined with gas chromatography following lipid transesterification. Samples of LL muscle were homogenized and prepared according to ISO 3100-1:1991 [25]. Total fat content was determined using the Soxhlet method [23], in which the samples are digested with acid hydrolysis and the fats are then extracted with petroleum ether using a Soxtherm 2000 automated device (Gerhardt, Munich, Germany). The obtained lipids were converted into fatty acid methyl esters (FAMEs) for gas chromatography (GC) analysis [26]. Approximately 60 mg (±10 mg) of the extracted fat were dissolved in 4 mL of isooctane. A methanolic potassium hydroxide solution (13.6 g KOH in 100 mL of methanol; 200 µ L) was added and shaken vigorously twice for 30 sec with a 30sec interval. The solution was then neutralized with 1 g of sodium hydrogen sulphate monohydrate. When crystals precipitated, 500 µ L of the solution were transferred into a

Meat Quality Traits
Post mortem measurements of muscle pH were determined at longissimus thoracis et lumborum (LTL) muscle 45 min (pH 45 ) and 24 h (pH 24 ) after slaughter with an HI 99613 portable meat pH meter (Hanna Instruments, Woonsocket, RI, USA). Drip was measured using the EZ-DripLoss method [21] after 48 h of cooling at 4 • C. The Colour of the LTL samples (the average of three measurements) was evaluated after 20 min of blooming using a Minolta CR-410 colourimeter (Minolta Camera Co. Ltd., Osaka, Japan) with a D65 light source and 10-degree standard observer. Light reflectance scores for CIE L*a*b*, chroma (saturation; C*) and hue angle (h • ) were determined.

Chemical Composition and Fatty Acids
The chemical composition of the samples was determined using standard analytical methods (moisture, [22]; total fat, [23]; nitrogen, [24]). The fatty acid composition of subcutaneous fat and IMF was determined with gas chromatography following lipid transesterification. Samples of LL muscle were homogenized and prepared according to ISO 3100-1:1991 [25]. Total fat content was determined using the Soxhlet method [23], in which the samples are digested with acid hydrolysis and the fats are then extracted with petroleum ether using a Soxtherm 2000 automated device (Gerhardt, Munich, Germany). The obtained lipids were converted into fatty acid methyl esters (FAMEs) for gas chromatography (GC) analysis [26]. Approximately 60 mg (±10 mg) of the extracted fat were dissolved in 4 mL of isooctane. A methanolic potassium hydroxide solution (13.6 g KOH in 100 mL of methanol; 200 µL) was added and shaken vigorously twice for 30 sec with a 30-sec interval. The solution was then neutralized with 1 g of sodium hydrogen sulphate monohydrate. When crystals precipitated, 500 µL of the solution were transferred into a vial, and 1 mL of isooctane was added. The container was sealed and shaken for 30 s. The fatty acid composition was determined with the procedure described by Petrović et al. (2010) [27] using a GC/MS 5975C device (Agilent Technologies, Palo Alto, CA, USA) equipped with a flame ionization detector and split/splitless injector. For injection, a TriPlus auto-sampler (Thermo Scientific, Austin, TX, USA) was used. Individual fatty acids in the sample were identified from the retention times of authentic standards (F.A.M.E C8-C24, Supelco, Bellefonte, PA, USA). Peak areas were determined using a Varian 4290 integrator, and the results were expressed as percentages of total identified fatty acids. The index of atherogenicity (IA) was calculated according to the formula proposed by Chen and Liu (2020) [28].

Statistical Analysis
The obtained data were analysed using the one-way ANOVA procedure of Dell Statistica (2015) [29]; the Tuckey HSD test was used for the determination of significance between the investigated groups of pigs. Violin plots were plotted using the ggpubr [30] and ggplot2 [31] package in the R environment [32].

Carcass Traits
Carcass traits of the investigated pigs are presented in Table 2. At the predetermined LW of 160 kg, the Black Slavonian pigs from the NAT pork chain had lower muscle thickness and significantly higher (p < 0.001) fat thickness than the INT fatteners, and the fatteners from the NAT chain showed a higher production of fat (p < 0.05) and lower leanness (p < 0.05) those from the INT chain. These results are in line with the results reported for other European and Asian native breeds, which are not selected for leaner carcasses and so exhibit higher fat thickness values than different genetic lines of modern pig breeds [33,34]. Compared to the INT fatteners, pigs from the NAT chain exhibited shorter carcass lengths, shorter ham lengths, and smaller circumferences. In line with the results obtained for the carcass traits, the dissection of the carcasses showed that the INT pigs were characterised by higher weights of ham, shoulder, neck, and tenderloin. On the other hand, pigs from the NAT pork chain produced carcasses with a higher weight of the belly/rib part, which corresponds to the combined production type of this breed with the affinity for a more pronounced production of adipose tissue in their carcasses. These results are similar to those reported by Wojtysiak and Połtowicz (2014) [34] for the native Puławska breed and Polish Large White pigs slaughtered at 100 kg LW. Interestingly, a higher loin weight (and its share in the carcass) in BS pigs from the NAT chain than in heavy fatteners from the INT pork chain was observed. Contrary to the results of this study, both Puławska and Creole breeds exhibited lower loin weights compared to modern pig breeds when slaughtered at 100 and 90 kg LW, respectively [34,35]. The disagreement between our findings and results on Puławska and Creole breeds probably occurred due to the lower age and slaughter weight of pigs from these trials compared to the LW and the age of animals from the present study. The composition of pig carcasses obtained by dissection, providing thorough insight into different tissues of the main parts, is presented in Table 3. As expected, the carcasses of commercial hybrids from the INT pork chain were superior to those of the BS pigs from the NAT chain regarding muscle tissue. These carcasses also had more bone in all of the cuts. On the other hand, native breeds, which are not subjected to selection based on accelerated growth rates and increased muscle production, are prone to produce more fat in the carcasses [36], as in the present case. In all dissected cuts, pigs from the NAT chain had higher weights and shares of fat tissue, demonstrating their ability to deposit adipose tissue, especially in terms of subcutaneous and intermuscular fat. This greater affinity for the accretion of adipose tissue is even more pronounced at higher slaughter weights when the proportion of adipose tissue increases and lean tissue declines [37]. In the present study, pigs were slaughtered at approximately 160 kg LW, which is considered to be optimal for the production of dry/cured products [38], so a higher share of adipose tissue in all dissected parts of the carcasses originating from both pork chains was observed. In the investigation comparing the carcass traits of Iberian pigs (IB) with F1 crossbreds of the Large White x Landrace (LWxL) cross raised to approximately 160 kg LW, lower mean weights (p < 0.05) of ham, neck, and tenderloin in the IB pigs relative to LWxL crosses were found; these results comply with those of the present study, although the difference for the neck weight in our study was not significant (p > 0.05). The mean weight of the belly was higher in IB pigs than in F1 LWxL pigs (p < 0.05), which is also consistent with the findings of the present study. Additionally, in their research on the local Basque breed, Lebret et al. (2014) [39] found that the Basque breed exhibited a lower proportion of hams than Large White pigs, which is in accordance with the results of our study. Despite the differences in the presentation of cuts, the results regarding the shares of ham and shoulder of Spanish native breed (Cerdo Iberico) slaughtered at heavy weights (156-170 kg) were similar to those obtained in this study [40,41]. Similar relations of main tissues in local unselected breeds were also found by other authors [42,43].
The carcass composition of pigs from the INT pork chain in terms of cuts in the present study was similar to those in other populations of pigs selected for high lean yields slaughtered at heavier live weights, e.g., in Brazilian crossbred pigs researched by Bertol et al. (2015) [42].

Meat Quality
The differences in meat quality traits between fatteners from investigated pork chains are presented in Table 4. The Black Slavonian pigs from the NAT chain had higher pH values (both initial and final), lower drip, lightness (L*), yellowness (b*) and hue angle (h • ) than the INT hybrids. It is well-known that the pH value significantly contributes to the overall quality of meat and is dependent on many pre-slaughter factors, with genetic background and stress being predominant [44]. Although the pH measured 45 min post mortem was at an acceptable level in both breeds, the ultimate pH value measured 24 h after the slaughter was quite low in pigs from the INT chain (<5.5; p = 0.0043) indicating a faster rate of post mortem glycolysis due to higher amount of fast twitch oxidative fibres observed in modern breeds, as well as their higher stress susceptibility compared to native breeds [45]. In agreement with the present results, the local Basque breed also exhibited higher initial and final pH values compared to fatteners originating from the modern Large White breed [39]. On the other hand, in research comparing the meat quality of Casertana native pig and modern breeds (Duroc and Large White), Maiorano et al. (2013) [46] reported higher initial pH values in the Casertana breed, though no difference was found between breeds in pH 24 value. The observed pH 24 of the Black Slavonian pig was shown to be higher than that of both Bisaro and Alentejano pigs [47], as well as Cinta Senese pigs [48], indicating the lower glycolytic capacity of the Black Slavonian pig compared to these two Portuguese and one Italian indigenous pig breeds.
A significant difference in drip loss between meat samples from investigated pork chains was observed, with meat from the NAT chain showing a favourable value for this trait. On the other hand, meat from the INT pork chain exhibited excessively high drip (p = 0.0032). The low drip-loss values determined in the NAT chain were associated with the higher pH of their LL muscles compared to modern hybrids, but the age of the animals, which was higher in animals in the NAT chain than those in the INT pork chain, also contributed. On the other hand, the drip loss of the meat from the NAT chain was higher than that reported for Cinta Senese pigs (1.89%; [48]), Basque pig (0.55-1.11%; [47]) and both Bisaro and Alentejano pigs (1.92% and 0.59%; [47]). However, this difference between native pig breeds has no practical importance, as it was favourable in all cases. Compared to PIC pigs from the INT chain, meat originating from the NAT pork chain was darker (lower L* values); however, no significant difference was observed for a* values. In line with the results of this study, Serra et al. (1998) [49] determined lower L* values in Iberian pigs (Guadyerbas line) compared to Landrace pigs, but no significant differences between the two breeds were observed for a*. The authors concluded that the darker meat of the Iberian pig is probably a result of the higher percentage of haem pigments found in this breed. On the other hand, opposite to the results of our study, meat from the Casertana breed had darker meat, though it also had a more pronounced red colour, than the meat from Duroc crosses and Large White animals [46].
Meat from the NAT pork chain animals tended to be less yellow with a lower hue angle compared to meat from the INT chain (p = 0.0517), indicating that meat from BS pigs diverged less from the true red axes [50]. In concordance with our results, Serra et al. (1998) [49] also reported lower h • values in meat from Iberian pigs compared to meat from modern breeds. The obtained h • values of meat originating from BS pigs was lower than values obtained for the Casertana breed [46], as well as Alentejano pig and Bisaro pigs [47].

Chemical Composition and Fatty Acid Profile
As shown in Table 5, significant differences between analysed groups for most of the chemical compounds were observed. Meat samples from the INT chain had a higher collagen content (p = 0.0002) and protein percentage (p = 0.0006) compared to the NAT chain pork. On the other hand, no significant differences were found for the moisture content between investigated groups. In agreement with the present results, lower collagen contents were reported for the French native Basque pig compared to the Large White breed [46] and for the Nero Siciliano breed compared to the Landrace breed [51]. As argued by Lebret et al. (2015) [45] the difference between autochthonous and conventional breeds in collagen content indicates its lower 'dilution rate' by muscle fibres in autochthonous breeds, as well as the higher thermal stability of collagen. Opposite to the present results, Kasprzyk and Bogucka (2020) [1] found a higher protein content in the Puławska breed than in the DanBred commercial hybrid. The lower protein content found in meat from the NAT pork chain could be due to the larger adipogenic profile of BS pigs compared to the leaner PIC hybrids from the INT chain.
A significantly higher IMF percentage (p = 0.0294) was observed in the meat of NAT chain pigs than in the INT chain (Table 5). According to Bejerholm and Barton-Gade (1986) [52], only an IMF content higher than 2% can have noticeable effects on sensory attributes of pork, and the benchmark for optimal taste and consumer acceptability is between 2.5 and 3.0% [53]. The mean value for meat from the NAT chain in this study was well-above this range, while the INT chain meat exhibited an IMF average even lower than 2.0%, indicating the lower sensory acceptability of their meat compared to meat originating from the NAT pork chain. The observed capacity for increased IMF content in BS pigs is predominantly a consequence of the breed's history and the contribution of Chinese breeds to its development, but it could also be attributed to the fact that native pig breeds have a higher capacity for lipid deposition [54] and a higher oxidative muscle metabolism compared to modern breeds, as reviewed by Poklukar et al. (2020) [36].
The obtained IMF values for the meat from the NAT chain were higher than those reported for Krškopolje [55], Celta [56] and Prestice Black-Pied [57] pigs, but they were lower than those for Iberian [58] and Laiwu [59] pigs.
We noted a high variability in IMF content of meat from the NAT pork chain (Table 5), indicating the need to carefully select individuals for crossbreeding. This variation in IMF seems, however, to be quite characteristic for local unselected breeds, as similar variations have also been reported in other European local pig breeds, e.g., Alentejano pig, Majorcan Black pig, Mora Romagnola pig, Swallow-belly Mangalitza, Cinta Senese pig, Iberian pig, Nero siciliano pig, Turopolje pig and Nero Casertano breed [13].
The fatty acid profile of LTL muscle in the two investigated pork chains is presented in Table 6. Meat samples from the NAT chain significantly differed from those from the INT chain in almost all investigated fatty acids. It is known that saturated fatty acids increase the risk of diabetes and cardiovascular diseases, while unsaturated fatty acids are beneficial for human health and associated with meat flavour [14,60]. Compared to the INT samples, NAT chain LTL muscles had significantly lower proportions of potentially harmful palmitic acid (C16:0) and higher proportions of beneficial unsaturated fatty acids, such as palmitoleic acid (C16:1n-7), oleic acid (C18:1n-9), gamma-linoleic acid (C18:3n-6) and nervonic acid (24:1n-9). Additionally, the NAT chain samples exhibited lower proportions of stearic C18:0 fatty acid, which (together with palmitic C16:0) is an indicator of de novo lipogenesis, suggesting not only a lower activity of the malic enzyme in their fatty tissue [39] but also that meat from the NAT pork chain is more tender than INT chain samples, as this is a fatty acid with the largest influence on meat firmness [13].
It is known that one of the key factors influencing fatty acid composition is the animal's diet, as animals fed on grass or in woodland usually exhibit higher levels of polyunsaturated and monounsaturated fatty acids, as well as decreased levels of saturated fatty acids, compared to animals reared indoors and fed conventional diets. It can be observed from Table 6 that compared to the INT chain, meat from BS animals from the NAT chain exhibited a higher share (p = 0.001) of monounsaturated fatty acids and lower shares of PUFA (p = 0.0533) and SFA (p = 0.0001) in their total fatty acids.
The results of the present study are consistent with the results regarding other local breeds reared outdoors and fed either grass, acorn, or chestnut [48], as well as with reports on the fatty acid composition of Prestice Black-Pied breed and Puławska pig breeds raised indoors [1,57]. Furthermore, in their investigation on the differences between the French local Basque breed and the Large White breed reared in conventional and production systems to LW of 145 kg, Lebret et al. (2014) [39] found that Basque pigs reared outdoors had increased MUFA and PUFA levels and a decreased SFA share in total fatty acids compared to both Basque animals reared intensively and Large White pigs kept in a conventional production system. The authors concluded that alternative production systems (mainly outdoor) influenced the fatty acid composition within each of the studied breeds. Opposite to our findings, Yu et al. (2013) [61] found a significantly lower MUFA percentage in the Lantang breed than in Landrace pigs, while Barea et al. (2013) [62] and Serra et al. (1998) [49] found that Iberian pigs raised in intensive production system to up to 100-115 kg of LW had higher proportions of SFA and PUFA compared to modern breeds kept in the same production system. The observed discrepancy in PUFA content between those studies and our investigation can be attributed to the higher age of the animals in the present study at which the deposition rate of MUFA is much larger than PUFA. It is well-known that pigs cannot produce PUFA and their content in fatty tissue is dependent on the PUFA incorporated into their diet. High dietary PUFA has the ability to decrease de novo fat synthesis and total SFA content [63]. From Table 6, it can be observed that the LTL muscle of animals from the INT chain had higher total PUFA and SFA content compared to those from the NAT chain, indicating the possibility to optimise the contents of fatty acids in both breeds through diet.
On the other hand, the attempts to enhance the nutritional quality by increasing MUFA and PUFA contents can lead to a range of problems, including the reduced shelf life caused by the rapid lipid oxidation for which PUFA are susceptible. Moreover, the oxidation of lipids can significantly deteriorate the sensory traits of pork products such as flavour, texture, mouth feel, and juiciness [64].
The main parameters used for the assessment of lipid nutritional quality are the PUFA/SFA ratio, which should be around 0.4 [65], and the index of atherogenicity (IA), which characterizes the atherogenic potential of fatty acids and in meat ranges from 0.165 to 1.32 [28]. In meat samples originating from both chains studied here, the PUFA/SFA ratio was around 0.16, which is well-below the proposed threshold and also in line with the results of studies on other local and modern pig breeds [66,67]. The atherogenic potential of the investigated meat samples was within the expected range. No significant differences (p > 0.05) were observed between investigated pork chains for the two nutritional quality indices.

Conclusions
The results of this study showed major differences in carcass traits, meat quality, and chemical composition between the meat from the NAT and INT pork chains, with NAT chain samples presenting overall better meat quality traits and higher IMF percentages. Additionally, NAT samples had a higher MUFA content and decreased SFA content compared to INT chain meat, indicating a need for the optimization of the diet composition administered as either additional in case of BS pigs from NAT or base in PIC hybrid pigs from the INT chain. Additionally, the improvement of a production system environment with more movement and less fighting could be beneficial for the improvement of meat quality traits in the INT chain.
Due to the observed differences, predominantly in meat quality and chemical composition (especially regarding the fatty acid profile), it can be concluded that meat from the NAT chain, despite the lower leanness of their carcasses, is more suitable for the production of dry/cured products. These results can serve as a basis for the branding of special commodities for a niche market originating from pork chains based on native pig breeds kept in extensive production systems.