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Poor animal welfare is a growing issue of concern all over the world. During pre-slaughter phases, some activities, if poorly performed, lead to stress reactions in animals. Animals’ responses to a great extent depend on species, breed, sex and age of animal. Food and water deprivation, exposure to unfavourable environmental conditions, improper handling and social mixing are just some indicators of compromised animal well-being. All these detrimental activities lead to the development of carcass and meat quality defects. Among them, important defects are untimely death of animals, body weight loss, carcass damage, and the two major meat quality defects, i.e. pale, soft, exudative (PSE) and dark, firm, dry (DFD) meats. Consumer dissatisfaction results, and with economic and financial losses, producers are placed in a disadvantageous position.

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The aims of this study were to determine the prevalence of carcass lesions in slaughtered pigs and to quantify their relationships with different animal characteristics, pre-slaughter factors, blood measurements, performance indices, carcass composition and meat quality traits. Data was recorded for 30 journeys referring to 1080 market-weight pigs that originated from 15 commercial small-scale finishing farms. Carcass lesions were visually assessed on the slaughterline in different parts of the carcass, i.e., anterior, middle and posterior, using a three-point scale. Complete blood count was investigated. The following performance indices and carcass composition traits were measured: average lifetime daily weight gain, live, hot and cold carcass weights, cooler shrinkage, dressing percentage, backfat thickness and meatiness. Meat pH and temperature were measured 45 minutes postmortem. Of the 1080 pigs slaughtered in 30 batches, 70.28% displayed some degree of lesions on the carcass (moderate – 30.00%; severe – 40.28%). The carcass lesions were the most prevalent (50.20%) in the posterior part of the pig carcass. RYR1 genotype, live weight, loading density, lairage time, lairage density and slaughter season affected the carcass lesion prevalence. The presence of carcass lesions, irrespective of severity, was associated with alterations in blood measurements in slaughtered pigs, indicating compromised animal welfare. The presence of severe carcass lesions in slaughtered pigs was significantly associated with increased meat pH45min, which led to the highest occurrence of dark, firm and dry pork. In contrast, there was strong evidence of association between the presence of moderate carcass lesions in slaughtered pigs and both decreased meat pH45min and increased meat T45min, which led to the highest occurrence of pale, soft and exudative pork among the carcass lesion groups. In conclusion, this study showed a high prevalence of carcass lesions in slaughtered pigs, whereby the risk of their occurrence was affected by both animal characteristics and pre-slaughter conditions. Also, the presence of carcass lesions in slaughtered pigs, irrespective of severity, was significantly associated with alterations in the blood measurements and pork quality.

One of the strategies for overcoming global climate change threatening to decrease maize yield is early sowing. To contribute to the development of cold‐tolerant hybrids this research focused on the genetic background's comparative analysis in maize inbreds with good combining ability. Leaf whole‐transcriptome sequencing of 46 maize genotypes revealed 77 differentially expressed genes (DEGs) between Lancaster and other heterotic groups (i.e. BSSS, Iowa dent, Ohio), referred to as non‐Lancaster group, under optimal growing conditions. Cold test of the subset of four Lancaster and four non‐Lancaster lines showed that the former were cold sensitive and the latter cold tolerant. Cold‐induced expression analysis of seven DEGs in eight lines revealed different expression regulation dependent on the duration of cold exposure and genetic background for six out of seven analysed genes—chloroplast ATP‐sulphurylase, photosystem II cytochrome b559 alpha subunit, CIPK serine‐threonine protein kinase 15, glutamyl‐tRNA reductase, photosystem II reaction centre protein I and Calvin cycle CP12‐chloroplastic‐like encoding genes. The results imply that differently regulated basic processes between Lancaster and non‐Lancaster maize group involve, at least, photosynthesis and sulphate assimilation, contributing to their different cold response and different adaptation to low temperatures.