Dietary profiles of wild carnivores and Blastocystis occurrence: The case of the endangered Iberian lynx (Lynx pardinus) and systematic review

Authors: CEBALLERO-GOMEZ, JAVIER - Universidad De Cordoba; AVALOS, GABRIEL - National Center For Microbiology, The Institute Of Health Carlos Iii; MATAS-MENDEZ, PABLO - Alfonso X El Sabio University; FIGUEIREDO, ANA - University Of Aveiro (UA); CASTRO-SCHOLTEN, SABRINA - Universidad De Cordoba; JIMENEZ-MARTIN, DEBORA - Universidad De Cordoba; KOSTER, PAMELA - National Center For Microbiology, The Institute Of Health Carlos Iii; Santin, Monica; BAILO, BEGONA - National Center For Microbiology, The Institute Of Health Carlos Iii; CANO-TERRIZA, DAVID - Universidad De Cordoba; SARMENTO, PEDRO - Institute For Nature Conservation And Forests; NEVES, NUNO - Institute For Nature Conservation And Forests

Submitted to: Research in Veterinary Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/20/2024
Publication Date: 12/26/2024
Citation: Ceballero-Gomez, J., Avalos, G., Matas-Mendez, P., Figueiredo, A.M., Castro-Scholten, S., Jimenez-Martin, D., Koster, P.C., Santin, M., Bailo, B., Cano-Terriza, D., Sarmento, P., Neves, N. 2024. Dietary profiles of wild carnivores and Blastocystis occurrence: The case of the endangered Iberian lynx (Lynx pardinus) and systematic review. Research in Veterinary Science. 184: 104418. https://doi.org/10.1016/j.rvsc.2024.105518.
DOI: https://doi.org/10.1016/j.rvsc.2024.105518

Interpretive Summary: Blastocystis is a microorganism commonly found in the gut of several animal species including humans. Despite the intense research conducted in the past decades, we still do not fully understand many aspects of the biology and epidemiology of Blastocystis, including its clinical significance. An intriguing Blastocystis feature is that its occurrence seems linked to the dietary requirements of the host species considered, with herbivores typically having higher prevalences than carnivores. To investigate this issue further, we examined fecal samples of Iberian lynxes in Spain and Portugal, as a paradigmatic species of hypercarnivorism, for the presence of Blastocystis. In addition, we systematically revised the studies reporting the presence of this microorganism in free-ranging and captive wild carnivores. Blastocystis was not detected in any of the 273 Iberian lynx’s fecal samples investigated, which is consistent with the epidemiological and molecular data generated from the systematic review. This data indicates that hypercarnivores tend to have lower Blastocystis prevalence rates than mesocarnivores or omnivores. Many of the Blastocystis findings seemed the result of accidental acquisition through consumption of prey animals or contaminated water/feed. This information will be useful to other scientists, veterinarians, and public health agencies to better understand transmission, zoonotic potential, and public health importance of intestinal protists.

Technical Abstract: Recent molecular and metagenomic studies have revealed that the obligate anaerobic protist Blas-tocystis is found more prevalently and with higher subtype diversities in herbivore species than in carnivore species. However, information on wild carnivore species is scarce. Here, we investigated the presence of Blastocystis by molecular methods in fecal DNA samples of free-ranging and captive Iberian lynxes from Spain (n = 243) and Portugal (n = 30). In addition, a systematic review was conducted to obtain information on the Blastocystis prevalence rates and subtype diversities re-ported in free-living and captive wild carnivores worldwide during the period 2000–2024. Blasto-cystis was not detected by PCR in any of the samples investigated. Analyses of the data gathered from our systematic review revealed that Blastocystis is uncommon either in free-living (2.3%, 29/1288) or captive (8.6%, 95/1105) wild carnivore species. Many of these findings seem to result from accidental acquisition via prey animals, scavenging, contaminated water/feed (free-ranging wild carnivores), or cross-species transmission among animals sharing enclosures (captive wild carnivores). Comparative metagenomic studies analyzing gut microbiota profiles of carnivores are needed to fully understand how microbial communities affect Blastocystis colonization.