Fattening and carcass traits in growing pigs of different genotypes and their relationship with blood serum biochemical parameters

This study presents the results of investigations into blood serum biochemical parameters, as well as fattening and carcass traits, in Hungarian-origin Large White pigs with different genotypes of the melanocortin-4 receptor (MC4R) gene. The serum biochemical parameters, including total protein concentration (g/L), urea concentration (mmol/L), aspartate aminotransferase (AST) activity (U/L), and alanine aminotransferase (ALT) activity (U/L), were within the physiological reference ranges for clinically healthy animals. Analysis of performance testing and slaughter data demonstrated that pigs of this breed and origin exhibited high fattening performance and desirable carcass characteristics. In terms of age at reaching 100 kg body weight, backfat thickness measured at the level of the 6th–7th thoracic vertebrae, and chilled carcass length, the animals exceeded the minimum requirements for the Elite breeding class by an average of 13.76 %. Significant differences between pigs of Group I (MC4RAG) and Group II (MC4RAA) were observed for average daily gain (41.5 g, t = 4.18), age at reaching 100 kg body weight (3.8 days, t = 2.45), backfat thickness at the level of the 6th–7th thoracic vertebrae (1.8 mm, t = 3.00), chilled carcass length (1.9 cm, t = 3.45), maximum (anterior) carcass width (2.0 cm, t = 2.46), and minimum (posterior) carcass width (1.2 cm, t = 2.30). The difference in the Tyler index between the two experimental groups was 17.63 points (t = 4.65). The pairwise correlation coefficients between blood serum biochemical parameters and the fattening and carcass traits of Hungarian-origin Large White pigs, including animals with different MC4R genotypes (MC4RAA and MC4RAG), ranged from -0.854 to +0.821. The proportion of statistically significant correlations was 29.16 %, 54.16%, and 25.00 %, respectively.