Different housing technology, breed, age and nutrition can contribute to changes in the composition of microbial communities in pigs. Faecal samples from groups of Mangalica and commercial pigs were collected and analysed by qPCR in order to identify changes and differences regarding the quantity of total faecal bacteria, Prevotella genus, Lactobacillus spp., Bifidobacterium spp., Enterococcus spp. and the family Enterobacteriaceae. In both Mangalica and commercial pig samples, quantities of total faecal bacteria increased from weaner pigs to lactating sows. The relative quantity of total bacteria was larger (p<0.05) in Mangalica growers and lactating sows compared to commercial pigs. The ratio of Prevotella genus in total bacteria was higher (p<0.05) in Mangalica growers and lower in Mangalica lactating sows compared to respective commercial groups. The ratio of Lactobacillus spp. was largest (p<0.05) in samples of Mangalica boars, whereas ratios of Bifidobacterium spp. were greater (p<0.05) in Mangalica weaners, growers, and boars. Faecal samples of Mangalica growers contained a higher ratio of Enterobacteriaceae in total bacteria, whereas Enterococcus spp. was more prevalent in commercial weaner pigs and boars (p<0.05). Considerable changes in faecal bacteria communities were observed in association with different age and utilization.

In order to identify potential variances in gene expression of phenotypically different pig breeds, six fat-metabolism-related genes were analyzed in backfat and muscle tissues of fat-type Mangalica (MAN), Mangalica x Duroc (MD), and lean-type Hungarian Large White (HLW) and Pietrain x Duroc (PD) pigs by means of quantitative reverse transcription PCR (qRT-PCR). Higher (P < 0.05) adipocyte fatty-acid-binding protein (A-FABP) expression was observed in backfat and muscle tissues of purebred and crossbred MAN than in those of HLW and PD. In all breeds and crosses, adiponectin (ADIPOQ) was predominantly expressed in backfat at a similar level (P > 0.05), whereas muscle ADIPOQ expression was highest (P < 0.05) in MAN and MD. Levels of fatty acid synthase (FASN) mRNA were greatest in MAN, moderate in MD, and lowest in HLW and PD backfat and muscle. The fat mass and obesity-associated gene (FTO) was more abundant in MAN and MD backfat, whereas muscle expressions did not differ (P > 0.05) between breeds. Regarding leptin (LEP) expression, MAN produced the greatest levels in backfat, while HLW produced the lowest. In muscle, highest LEP was detected in MAN and MD. Between groups, perilipin 2 (PLIN2) was expressed similarly in backfat; however, PLIN2 was more abundant in muscle of MAN and MD than in that of HLW and PD. Differences in gene expression can contribute to the development of the characteristic fatty phenotype in MAN pigs. The identification of differentially expressed genes facilitates targeted sequencing and genotyping efforts for further studies.