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Important centres for the pork industry have become growth in arid regions in the world and pig production needs alternatives to increase the productivity. A screening of predominant Lactobacillus strains from healthy piglets was performed in order to select specific probiotics. The ability of 164 strains to grow at different temperatures and concentrations of NaCl was evaluated. Results showed that all of them grew at 45 degrees C, 75% at 50 degrees C and 64% resisted 680 mM of salt. Adhesion to mucus and gastric mucin was evaluated showing 45% of strains isolated from faeces were able to adhere whereas 71% of strains from mucus showed mucus binding activity. Among the 164 isolates, 27 adhesive strains were identified using comparisons with 16S rDNA and intergenic 16-23S sequences. Results indicated that L. fermentum and L. reuteri were the most common species in faeces and mucus, respectively. Ability to grow in gastrointestinal mucus was evaluated showing that 92.6% of strains were able to replicate. Additionally, bacterial strain grown in 3.5% MRS with bile salts was evaluated. These results indicated that animals inhabiting isolated arid coasts are a rich source of probiotics, which resist adverse environmental conditions and can colonise the intestinal tract of pigs.