Background and Aim: Natural resistance-associated macrophage protein 1 encoding gene (Nramp1) plays a role in immune response and disease resistance. This study aimed to investigate the polymorphisms of Nramp1 intron 6 concerning Salmonella shedding and hematological traits in pigs. Materials and Methods: A total of 40 commercial pigs (three-way Large White x Landrace x Duroc cross) were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and analyze the relationship between the polymorphisms of the Nramp1 gene and Salmonella fecal shedding and hematological parameters. Results: Nramp1 was shown to be polymorphic in these pigs. The Nramp1 gene has two alleles (A and B) and two genotypes (AB and BB). The BB genotype had a higher frequency than the AB genotype. A significant relationship between the BB genotype and the number of Salmonella in feces compared to the AB genotype (p < 0.05) on 7 days post-inoculation (DPI) was revealed in the association analysis. The single-nucleotide polymorphism at intron 6 in the Nramp1 gene was linked to white and red blood cells 2 and 7 DPI (p < 0.05). Conclusion: The Nramp1 gene was suggested by these findings to be potentially used as a molecular marker for the genetic selection of disease susceptibility in pig breeding.

Objective: This study was conducted to investigate polymorphisms of the melanocortin-4 receptor (<i>MC4R</i>) and insulin like growth factor 2 (<i>IGF2</i>) genes and to evaluate the growth traits affected by such polymorphisms in Thai native (Kradon) pigs.Methods: Blood samples and productive data from 91 Kradon pigs were collected. DNA was extracted and quantified, the <i>IGF2</i> and <i>MC4R</i> genes were amplified, and the polymerase chain reaction (PCR) produces were digested using the PCR-restriction fragment length polymorphism (PCR-RFLP) technique. Genotyping was performed, and the association between genotypes and growth traits on the birth and weaning weights were evaluated.Results: The IGF2 intron7 g.162G>C variations in Kradon pigs were found in three genotypes: i) GG, ii) GC, and iii) CC. The GG genotype frequency was the highest followed by the GC and CC genotypes. The frequencies of the G and C alleles were 0.703 and 0.297, respectively. The <i>MC4R</i> genotype was found in only one genotype (GG). The <i>IGF2</i> gene pattern was not associated with birth weight traits, whereas the <i>IGF2</i> gene pattern was related to the weaning weight trait in Kradon pigs. Pigs with the CC and GC genotypes had higher weaning weights than ones with the GG genotype (p<0.001).Conclusion: Thai native Kradon pigs with the CC and GC genotypes of the <i>IGF2</i> gene have higher weaning weights than pigs with the GG genotype.