Campylobacter lari is a thermotolerant bacterium that sporadically causes gastrointestinal diseases in humans and can be found in wildlife and the environment. C. lari is an understudied species, ...especially in wild birds such as gulls. Gulls are potentially good carriers of pathogens due to their opportunistic behavior and tendency to gather in large flocks. During winter and their breeding period, 1753 gulls were captured, and cloacal swabs were taken to be tested for the presence of C. lari. From isolated bacteria, the DNA was sequenced, and sequence types (ST) were determined. Sixty-four swabs were positive for C. lari, and from those, forty-three different STs were determined, of which thirty-one were newly described. The whole genome was sequenced for 43 random isolates, and the same isolates were tested for antimicrobial susceptibility using the broth microdilution method to compare them to WGS-derived antimicrobial-resistant isolates. All the tested strains were susceptible to erythromycin, gentamicin, and chloramphenicol, and all were resistant to ciprofloxacin. Resistance to ciprofloxacin was attributed to a gyrA_2 T86V mutation. Genes connected to possible beta-lactam resistance (blaOXA genes) were also detected.
This study aimed to assess the presence of thermotolerant Campylobacter spp., as one of the most important foodborne zoonotic pathogens, in three shellfish species: mussels (Mytilus ...galloprovincialis), oysters (Ostrea edulis) and queen scallops (Aequipecten opercularis). The samples were collected from nine locations in the Istrian aquatory, Croatia. Isolation of Campylobacter was done according to standard ISO method, and species were identified using multiplex PCR. Isolates identified as C. jejuni and C. lari were genotyped using multilocus sequence typing (MLST) to determine the potential source of contamination. Among 108 examined samples of bivalve molluscs, mussels dominated and were the only ones found positive for the presence of Campylobacter (25.6%). In total, 19 C. lari and 1 C. jejuni strains were isolated. C. lari isolates found in this study belong to 13 sequence types (STs), and 9 of them are newly described in this paper. Two out of the four previously described C. lari STs that were found in this study were previously found in human stool. The only C. jejuni isolate was found to be sequence type 1268, which belongs to ST-1275 clonal complex that is almost exclusively found in seabirds and can sporadically cause infection in humans. Regarding the obtained results, introducing surveillance of thermotolerant Campylobacter in shellfish in the Republic of Croatia is advised as an improvement for public health safety.
With increasing advances in telemetry technology, prospecting behaviour was identified in many seabirds; mostly in immatures, but also in adults - during pre-breeding and post-breeding periods and ...among failed breeders. However, prospecting has not yet been documented among active breeders. We equipped 17 Common terns Sterna hirundo with GPS-UHF data-loggers and tracked their movements during late incubation and chick rearing in continental Croatia. We monitored the fate of their clutches until chicks left the nest. Birds of both sexes visited other breeding colonies within relatively short distances, while they still had active nests. These results confirm for the first time the presence of prospecting trips during incubation and chick-rearing in active breeders. Such behaviour probably developed because quick and unpredictable changes in their freshwater habitats can cause failure of whole colonies, forcing them to renest at other sites during the same breeding season. Prospecting during the first breeding attempt might shorten the renesting interval, and increase renesting success when multiple breeding sites are available on an easily accessible area. With increasing vulnerability of colony sites due to climate change, studies of scattered colonies are needed to better understand renesting and adult prospecting strategies.
Galebovi su skupina morskih ptica raširenih diljem svijeta koje su važan rezervoar Salmonella spp. Salmoneloza je druga najčešće prijavljena gastrointestinalna infekcija u ljudi i razumijevanje uloge ...koju divlje ptice imaju u širenju Salmonella spp. može pomoći u poboljšanju zdravlja ljudi i domaćih životinja. Mobilnost i migracijska sposobnost čini galebove vrlo zanimljivom skupinom za istraživanje zbog njihove potencijalne uloge u širenju patogena. Kroz ovaj rad prikazujemo raznolikost i prevalenciju Salmonella spp. kod nekoliko vrsta galebova ulovljenih na odlagalištu otpada tijekom zime u Zagrebu kroz devetogodišnje razdoblje, 2014.-2022. Ukupno je uzorkovano 1083 obrisaka kloake od šest vrsta galebova: riječni galeb (Larus ridibundus), galeb klaukavac (L. michahellis), pontski galeb (L. cachinnans), burni galeb (L. canus), tamnoleđi galeb (L. fuscus) i srebrnasti galeb (L. argentatus). Ukupna prevalencija Salmonella spp. je 5,82 % sa 16 identificiranih serotipova. S. Typhimurium ima najveću zastupljenost (47,62 %), zatim S. Enteritidis (12,69 %) i S. Infantis (9,52 %). Prema istraživanjima prisutnosti serotipova Salmonella spp. u galebova u Europi izolirana su njih 82, a najčešće dokazani je S. Typhimurium, zatim S. Agona i S. Enteritidis. Tijekom ovog istraživanja identificirana su tri serotipa koja ranije nisu izdvojena iz galebova S. Yalding i S. Reading
te jedan iz podvrste S. enterica subsp. diarizonae (IIIb_O:17; H:z10; H:e,n,x,z15).
Campylobacter lari is a thermotolerant bacterium that sporadically causes gastrointestinal diseases in humans and can be found in wildlife and the environment. C. lari is an understudied species, ...especially in wild birds such as gulls. Gulls are potentially good carriers of pathogens due to their opportunistic behavior and tendency to gather in large flocks. During winter and their breeding period, 1753 gulls were captured, and cloacal swabs were taken to be tested for the presence of C. lari. From isolated bacteria, the DNA was sequenced, and sequence types (ST) were determined. Sixty-four swabs were positive for C. lari, and from those, forty-three different STs were determined, of which thirty-one were newly described. The whole genome was sequenced for 43 random isolates, and the same isolates were tested for antimicrobial susceptibility using the broth microdilution method to compare them to WGS-derived antimicrobial-resistant isolates. All the tested strains were susceptible to erythromycin, gentamicin, and chloramphenicol, and all were resistant to ciprofloxacin. Resistance to ciprofloxacin was attributed to a gyrA_2 T86V mutation. Genes connected to possible beta-lactam resistance (blaOXA genes) were also detected.
This study aimed to assess the presence of thermotolerant Campylobacter spp., as one of the most important foodborne zoonotic pathogens, in three shellfish species: mussels (Mytilus ...galloprovincialis), oysters (Ostrea edulis) and queen scallops (Aequipecten opercularis). The samples were collected from nine locations in the Istrian aquatory, Croatia. Isolation of Campylobacter was done according to standard ISO method, and species were identified using multiplex PCR. Isolates identified as C. jejuni and C. lari were genotyped using multilocus sequence typing (MLST) to determine the potential source of contamination. Among 108 examined samples of bivalve molluscs, mussels dominated and were the only ones found positive for the presence of Campylobacter (25.6%). In total, 19 C. lari and 1 C. jejuni strains were isolated. C. lari isolates found in this study belong to 13 sequence types (STs), and 9 of them are newly described in this paper. Two out of the four previously described C. lari STs that were found in this study were previously found in human stool. The only C. jejuni isolate was found to be sequence type 1268, which belongs to ST-1275 clonal complex that is almost exclusively found in seabirds and can sporadically cause infection in humans. Regarding the obtained results, introducing surveillance of thermotolerant Campylobacter in shellfish in the Republic of Croatia is advised as an improvement for public health safety.
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