Inferring the microbiota diversity of helminths enables depiction of evolutionarily established ecological and pathological traits that characterize a particular parasite-host interaction. In turn, these traits could provide valuable information for the development of parasitosis control and mitigation strategy. The parasite Anisakis pegreffii (Nematoda: Anisakidae) realizes the final stage of its life-cycle within gastric chambers of aquatic mammals, causing mild-to-moderate granulomatous gastritis with eosinophilic infiltrate, to severe ulcerative gastritis with mixed inflammatory infiltrate, often associated with bacterial colonies. However, its interaction with the host microbiota remains unknown, and might reveal important aspects of parasite colonization and propagation within the final host. MySeq Illumina sequencing was performed for the 16S rRNA gene from microbiota isolated from larvae, and uterus and gut of adult A. pegreffii parasitizing stranded striped dolphins (Stenella coeruleoalba). To assess the potential presence of Brucella ceti within isolated microbiota, Brucella-targeted real-time PCR was undertaken. In addition, TEM of the gastrointestinal tract of the infective third-stage (L3) and transitioning fourth-stage larvae (L4) was performed to characterize the morphological differences and the level of larval feeding activity. In total, 230 distinct operational taxonomic units (OTUs) were identified across all samples (n = 20). The number of shared taxa was lower than the number of taxa found specifically in each parasite stage or organ. The dominant taxon was Mycoplasmataceae (genus Mycoplasma) in the gut and uterus of adult A. pegreffii, whereas Fusobacteriaceae (genus Cetobacterium) was the most abundant in 40% of larvae, alongside Mycoplasmataceae. No B. ceti DNA was detected in any of the microbiota isolates. TEM revealed differences in gut ultrastructure between L3 and L4, reflecting a feeble, most likely passive, level of feeding activity in L3. Microbiota from L3 was more related to that of the gut rather than the uterus of adult A. pegreffii. Taxa of the larval microbiota showed qualitative and quantitative perturbations, likely reflecting the propagation through different environments during its life-cycle. This suggests an ontogenetic shift in the alpha and beta diversity of microbial communities from uterus-derived towards cetacean-derived microbiota. Although TEM did not reveal active L3 feeding, microbiota of the latter showed similarity to that of an actively feeding adult nematode.

A special part of archaeology, so-called archaeozoopathology or veterinary paleopathology is dedicated to studies of paleopathological changes in animal remains and contributes to the knowledge of ancient veterinary medicine and the history of diseases. In our study, we analyze paleopathological changes determined by gross observation and diagnostic imaging in the animal material originating from eight archaeological sites in Croatia. A standard archaeozoological analysis was carried out and specimens with visually detected macrostructural changes were radiographed. In total, 50 animal remains with altered macrostructure were identified in the archaeozoological material excavated from 2010 to 2022 at eight archaeological sites in Croatia. According to the taxonomic analysis, most of the bones with macrostructural changes originated from cattle (N = 27, 54% of the total number of bones with macrostructural changes), followed by the bones of small ruminants (N = 12, 24%) and pigs (N = 8, 16%). The horse, carnivore and chicken were represented with one bone each (2%). Radiological examination showed that three samples (6%) had a regular bone macrostructure, i.e., no pathological changes were visible upon radiological examination. The majority (64%) of pathologically altered bones are a consequence of keeping/working, followed by traumatic causes (20%). Changes in the oral cavity were found in 10% of specimens. Our study showed that gross examination will continue to be the primary method for the identification of pathologically altered remains in archaeozoological material. However, diagnostic imaging techniques such as radiography should be implemented to confirm or exclude suspected alterations and to help the classification of the specimen by etiology.

Mycobacterium avium subsp. avium is pathogenic mainly to birds, although cases of mycobacteriosis caused by these bacteria have also been reported in other animals and humans. Not much is known about the effects of this pathogen on otters. The aim of this study was to report for the first time the isolation of M. avium subsp. avium in wild otter and to describe its multidrug resistance profile. A female otter injured in a car accident was found dead and subjected to postmortem examination. Apart from the trauma changes, no other macroscopic pathological changes were detected. Bacteriologic examination revealed the presence of acid-fast bacilli in the lymph nodes, which were confirmed by molecular methods as M. avium subsp. avium. Antimicrobial susceptibility testing revealed susceptibility to clarithromycin and amikacin, but resistance to linezolid, moxifloxacin, streptomycin, isoniazid, trimethoprim/sulfamethoxazole, ciprofloxacin, doxycycline, and ethionamide. This is unusual for wild species, which generally should not come into contact with antimicrobials, and may suggest that multidrug-resistant MAC strains are circulating between wild and domestic animals. These results emphasise the need for additional epidemiological studies on non-tuberculous mycobacteria in wildlife and their implications for one health.

This study investigated the historical consumption of pork in Croatia through a comprehensive analysis of pig bones from six medieval archaeological sites, comprising three castles and three monasteries dating from the 13th to the 16th century A.D. Employing a detailed morphological analysis of pig bones and teeth, the study quantified the number of identified specimens (NISP) per site. On bones and teeth, identification of sex and age was performed, and butchery patterns were documented. The results revealed a significant presence of pork in the diet of castle and monastery inhabitants, with pig bones being the most abundant animal remains. Age analysis suggested a prevalence of juvenile pigs, predominantly males. The findings implied that from the 13th to the 16th century A.D., pork was a staple in the diet of castles and monasteries in continental Croatia, sourced from pig breeding outside these sites. Typically, male pigs aged under two years were delivered for consumption to these establishments.