Crossbreeding between Duroc and Pietrain breeds is widely applied in genetic improvement programs to enhance productivity and carcass quality, aligning with sustainability goals and consumer demands. Additionally, sex is a relevant factor influencing performance and carcass traits. This study evaluate performance, carcass characteristics, and primary cut weights in pigs from different genetic lines and sexes, as well as their interactions. A total of 600 pigs were evaluated across three sire lines: Line d- Duroc, Line H- Hybrid (Duroc and Pietrain), and Line P- Pietrain, including both females and immunocastrated males (ICM). At the end of the growing period, 120 animals with body weights closest to the pen average were selected for slaughter and carcass analysis. No significant interactions were observed between genetic line and sex (P ≤ 0.05). ICM showed superior average daily gain (ADG), final weight, feed conversion (FCR), and backfat thickness, while females had higher carcass yield and lean meat percentage. D and H lines outperformed P in carcass yield and weight, whereas P had greater backfat thickness but lower lean percentage and loin depth. For primary cuts, ICMs had heavier bellies, while females yielded more lean cuts. The results underscore the impact of genetic and sex-based selection on pork quality and sustainability.

Pork is a major source of animal protein worldwide, and its quality is influenced by pre- and post-slaughter procedures. Advances in molecular biology, particularly gene expression studies, support genetic improvement programs by enabling precise strategies to enhance meat quality and economic sustainability. This study evaluated meat quality traits and candidate gene expression in muscle and subcutaneous adipose tissue from different genetic lineages and sexes. A total of 120 pigs from three lineages—Line D (½ Duroc × ½ DB90), Line P (½ Pietrain × ½ DB90), and Line H (½ [Duroc and Pietrain] × ½ DB90); including immunocastrated males (IM) and females, were randomly selected. Meat quality was assessed using physicochemical parameters, and gene expression analysis was performed in 36 pigs using RT-qPCR with B2M, TBP, and RPL4 as references, and COL1A1, PRKAR2A, CAST, ADIPOQ, and PPARGC1A as targets. Lineage influenced drip loss and intramuscular fat, while lineage–sex interaction affected tenderness and color (L* and b*), and sex influenced b*. In muscle, sex affected COL1A1 and PRKAR2A, and lineage influenced COL1A1 and CAST. In adipose tissue, only CAST was lineage-dependent.

This study evaluated the performance of gestating and lactating sows supplemented with tributyrin from gestation until the end of lactation. Additionally, it assessed the effects of this supplementation on pig growth performance during the nursery phase. A total of 148 commercial-line sows (DB90 Brasil; parity 1–4; initial weight: 201.7 ± 12.2 kg) were used during gestation and lactation, along with 180 weaned pigs. A randomized block design was utilized with two dietary treatments during gestation and lactation, and a 2 × 2 factorial arrangement during the nursery phase. Data on sow body composition and productivity during gestation and lactation, as well as piglet performance during nursery, were collected. Treatment effects and interactions were analyzed using ANOVA with the MIXED procedure of SAS Version 9.0 (SAS Inst. Inc., Cary, NC, USA). Sows fed tributyrin tended to weigh 3.05 kg more (p = 0.053) and had 6.51% less backfat accumulation prepartum (p = 0.099). Supplementation reduced stillborns by 35.47% (p = 0.032) and increased litter weight at birth by 10.14% (p = 0.018). Additionally, there was a trend toward an 18.73% reduction in weight variability (p = 0.053) with more piglets weighing ≥1.4 kg. Sow and litter performance during lactation were not affected. Piglets from sows supplemented with tributyrin showed a trend for higher feed intake immediately post-weaning (p = 0.056). Tributyrin supplementation during gestation reduced stillborn rates and increased litter weight at birth.