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Abstract: Two genes (PRKAG3 and CAST) were screened for genotype incidence and their effect on green ham traits in pigs suitable for dry-cured ham production from three commercial crosses (in three countries France, Slovenia and Spain). Hams were genotyped for PRKAG3 Ile199Val, CAST Lys249Arg and CAST Ser638Arg polymorphisms and the traits of interest (green ham weight and fat thickness, pH in M. semimembranosus (SM), M. gluteus medius (GM) colour) were measured. The genotype frequencies as well as the effect of the studied genes varied according to the country, which used different genetic crosses and selection criteria for dry-cured ham processes. Regarding the association with traits of interest, we observed a significant effect of PRKAG3 Ile199Val polymorphism on green ham weight and colour grade in the French cross, on green ham fat thickness, colour grade and GM Minolta L⁎ and a⁎ values in the Slovenian cross, and on SM pH in the Spanish cross. The CAST Lys249Arg polymorphism affected green ham weight in Slovenian cross, whereas CAST Ser638Arg affected green ham colour grade in French cross. No effect of CAST polymorphisms on the traits of interest was found in Spanish cross. According to our results, PRKAG3 gene seems to be more influential on green ham traits important for dry ham production than CAST gene. However the results were different for each country, indicating possible interaction with other genetic or environmental factors. [Copyright &y& Elsevier]

Summary This study examined the frequency, morphological and immunohistochemical characteristics of the giant fibres in the longissimus muscle of local Krško polje pigs with different Ryr1 genotypes. Giant fibres were round-shaped and had significantly increased cross-sectional area compared with normal muscle fibres. Only fast-twitch glycolytic fibres were affected, usually showing enhanced succinate dehydrogenase activity. On the ultrastructural level, the dilation of the sarcoplasmic reticulum, swelling of mitochondria and destruction of myofilaments was observed. The incidence of giant fibres was the highest in Ryr1 dimutant pigs (Ryr1 nn), which also exhibited lower muscle pH1 than heterozygous (Ryr1 Nn) or pigs with the wild Ryr1 gene (Ryr1 NN). However, the giant fibres were also present in pigs free of Ryr1 gene mutation. Our results suggest that the giant fibre syndrome depends mostly upon the rate and intensity of early post-mortem glycolysis, which results in acidity of muscle tissue. We suppose that the giant fibre formation is a result of excessive intracellular lactate accumulation in some fast-twitch glycolytic fibres. This process could also explain the ultrastructural alterations and the consequent changes in the oxidative enzymes and myofibrillar ATPase staining pattern observed in our and some previous studies. [ABSTRACT FROM AUTHOR]

This study examined the quality of dry-cured hams produced from local pig breed and modern hybrids using two trimming methods. Hams (n = 24) of similar weight were harvested from local breed "Krškopolje pig" (KKP) and conventional hybrid pigs (CON). The left and right hams from KKP were trimmed according to "Kraški pršut" (K) and "Istrski pršut" (I), respectively, while the hams from CON were trimmed as "Kraški pršut", yielding 8 hams per treatment (K-KKP, I-KKP, K-CON). After processing, the samples of dry-cured hams (part with biceps femoris, semimembranosus and semitendinosus muscles) were collected and analysed for chemical composition, texture, sensory analysis and volatile profile. Dry-cured hams of local breed (K-KKP) had lower dehydration loss (due to thicker fat cover), moisture content and a w , softer and more plastic texture, with sensory analysis showing more marbling, softer, pastier texture, more pronounced herbal aroma and sweetness than K-CON. Trimming type was associated with higher dehydration loss (due to removed skin), lower moisture content and a w , higher salt content and harder texture, with sensory analysis showing more marbling, more surface moisture and herbal odour, harder and pastier texture, and sweeter and less bitter taste in I-KKP than K-KKP. The analysis of volatile compounds clearly distinguished the types of dry-cured hams, with each exhibiting a unique volatile profile that enabled differentiation based on breed or trimming. Overall, the study highlights some advantages of dry-cured ham from local pig breeds and shows how trimming affects product's characteristics., Competing Interests: Declaration of competing interest Authors declare no conflict of interests., (Copyright © 2025 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: The importance of local breeds as genetic reservoirs of valuable genetic variation is well established. Pig breeding in Central and South-Eastern Europe has a long tradition that led to the formation of several local pig breeds. In the present study, genetic diversity parameters were analysed in six autochthonous pig breeds from Slovenia, Croatia and Serbia (Banija spotted, Black Slavonian, Turopolje pig, Swallow-bellied Mangalitsa, Moravka and Krskopolje pig). Animals from each of these breeds were genotyped using microsatellites and single nucleotide polymorphisms (SNPs). The results obtained with these two marker systems and those based on pedigree data were compared. In addition, we estimated inbreeding levels based on the distribution of runs of homozygosity (ROH) and identified genomic regions under selection pressure using ROH islands and the integrated haplotype score (iHS)., Results: The lowest heterozygosity values calculated from microsatellite and SNP data were observed in the Turopolje pig. The observed heterozygosity was higher than the expected heterozygosity in the Black Slavonian, Moravka and Turopolje pig. Both types of markers allowed us to distinguish clusters of individuals belonging to each breed. The analysis of admixture between breeds revealed potential gene flow between the Mangalitsa and Moravka, and between the Mangalitsa and Black Slavonian, but no introgression events were detected in the Banija spotted and Turopolje pig. The distribution of ROH across the genome was not uniform. Analysis of the ROH islands identified genomic regions with an extremely high frequency of shared ROH within the Swallow-bellied Mangalitsa, which harboured genes associated with cholesterol biosynthesis, fatty acid metabolism and daily weight gain. The iHS approach to detect signatures of selection revealed candidate regions containing genes with potential roles in reproduction traits and disease resistance., Conclusions: Based on the estimation of population parameters obtained from three data sets, we showed the existence of relationships among the six pig breeds analysed here. Analysis of the distribution of ROH allowed us to estimate the level of inbreeding and the extent of homozygous regions in these breeds. The iHS analysis revealed genomic regions potentially associated with phenotypic traits and allowed the detection of genomic regions under selection pressure., (© 2022. The Author(s).)

The capability of near infrared (NIR) spectroscopy was examined for the purposes of quality control of the traditional Slovenian dry-cured ham "Kraški pršut." Predictive models were developed for moisture, salt, protein, non-protein nitrogen, intramuscular fat and free amino acids in biceps femoris muscle (n = 135). The models' quality was assessed using statistical parameters: coefficient of determination (R(2)) and standard error (se) of cross-validation (CV) and external validation (EV). Residual predictive deviation (RPD) was also assessed. Best results were obtained for salt content and salt percentage in moisture/dry matter (R(CV)(2)>0.90, RPD>3.0), it was satisfactory for moisture, non-protein nitrogen, intramuscular fat and total free amino acids (R(CV)(2) = 0.75-0.90, RPD = 2.0-3.0), while not so for protein content and proteolysis index (R(CV)(2) = 0.65-0.75, RPD<2.0). Calibrations for individual free amino acids yielded R(CV)(2) from 0.40 to 0.90 and RPD from 1.3 to 2.9. Additional external validation of models on independent samples yielded comparable results. Based on the results, NIR spectroscopy can replace chemical methods in quality control of dry-cured ham., (Copyright © 2011 Elsevier Ltd. All rights reserved.)