PCR-based detection ofHelicobacterspp. in mice from different animal houses in Rio de Janeiro, Brazil

Abstract

1Pathogenic microbial detection and control in breeding and experimental 2 laboratory animal facilities is essential to guarantee animal welfare, data validity and 3 reproducibility. Helicobacter spp. is known to severely affect mice health, mainly in 4 immunocompromised strains, what may affect experimental outcomes. This study 5 aimed to screen for Helicobacter spp. in mice from four different animal houses in Rio 6 de Janeiro, Brazil using a PCR for 16S ribosomal RNA. A pair of primers was designed 7 to specifically identify Helicobacter species that commonly infect laboratory mice. 8 Following PCR reaction, the expected 375 base pairs (bp) amplification product was 9 purified, sequenced and showed a 95% similarity when compared to deposited 10 sequences of Helicobacter hepaticus and Helicobacter bilis. Then, the presence of 11 Helicobacter spp. in both feces and intestines samples was analyzed. Helicobacter spp 12 DNA was detected in 59.6% of the fecal and 70.17% of the intestine samples. Although 13 Helicobacter spp screening is recommended by institutional animal health monitoring 14 programs worldwide it is still not mandatory by Brazilian animal welfare regulation. 15 Our study, the first to monitor Helicobacter species in laboratory mice in Brazil, 16 demonstrates the possibility of using a low cost, rapid molecular diagnostic test to 17 screen Helicobacter and highlights the importance of regular microbiological 18 verification of mice used for research in Brazilian animal houses.19 20