1,721,002 research outputs found
Parasitic infections in sea turtles and cetaceans in Mediterranean Sea waters, with a focus on the Adriatic Sea
Full text linkParasitic infections contribute to natural mortality in population of free ranging sea turtles and cetaceans worldwide. Notwithstanding all host-dependant factors influencing the outcomes of parasitic infections, some parasites, spanning from protozoan to helminthic taxa, have a high pathogenic potential and can cause fatal disease in these animals. Sea turtles blood flukes (Digenea: Spirorchiidae) are a main factor in mortality of populations of green and loggerhead turtles in Atlantic and Pacific Ocean. In order to explore presence and pathology of spirorchiidiasis in the Mediterranean area, data from 168 loggerhead turtles (Caretta caretta) stranded dead along North Western Adriatic coast were collected during a six-years period. Parasitological study and pathological findings revealed the presence of eggs and adult flukes of Hapalotrema mistroides and Neospirorchis – Neogen 11, with prevalence of 15.5% and 6.0% respectively. Mild lesions were observed, including multifocal granulomatous enteritis and chronic focal vasculitis of the major vessels. Egg emboli were found widespread in the tissues, mostly attributable to H. mistroides. Sequencing of rDNA markers (28S and ITS-2) and phylogenetic analyses revealed the identity of the Mediterranean isolates with Floridian specimens. Genetic analysis on the hosts led to the conclusion that the life cycles of both genera can be entirely supported by the Mediterranean ecosystem. To estimate the infection intensity, a new rapid method was set up. Correlation between spleen egg burden and fecal egg output was studied by means of statistical tests applied to splenic tissue and fecal material, revealing the absence of correlation and the unreliability of fecal burden to assess severity of the disease in vivo. Gastrointestinal helminth community of loggerheads was also studied, revealing a species diversity typical of demersal stage turtles and similar to that observed in other neritic areas of the Mediterranean.
As for cetaceans, crassicaudosis is considered one of most severe helminthic infections in these animals. Nevertheless, knowledge on the epidemiology of Crassicauda species is scarce, due to constraints of sampling free-ranging wild host species and to the difficulty of obtaining entire specimens suitable for morphologic studies. Presence and pathology of Crassicauda boopis were investigated in fin whales (Balaenoptera physalus) stranded along Italian coasts. Severe lesions linked to the presence of adult nematodes in circulatory system and kidneys were detected in five rorquals (5/7), associated with renal function impairment and arteritis of the mesenteric vessels linked to spirurid larvae migrans. Morphological studies enabled the identification of the adult nematodes as C. boopis. Sequencing of molecular barcode regions was performed on adult and larval nematodes from the whales; additionally, specimens of Crassicauda spp. isolated from toothed whales were morphologically and molecularly studied. A multigene analysis made on the barcode regions of rDNA and on the mtDNA revealed the ITS-2 spacer to be the most efficient marker in species differentiation inside the genus Crassicauda. This analysis opened new insights on the identity of the isolated larvae migrans and on the life cycles of these poorly known nematodes. Furthermore, during the parasitological examination, immature elements of the genus Pennella were recovered from one fin whale and described from a morphological point of view for the first time. Preliminary molecular data were obtained, with the aim of clarifying the taxonomy of the genus Pennella. The coccidian Toxoplasma gondii was detected in the tissues of one rorqual as well, likely associated with a chronic infection.
In conclusion, these parasitological surveys highlighted the importance of a continue monitoring of the health of these endangered species avoiding underestimating the potential impact of parasitic diseases in natural mortality
SPIRORCHIIDIASIS IN STRANDED LOGGERHEAD CARETTA CARETTA IN NORTHERN ADRIATIC SEA (ITALY)
No full textUnusual mass stranding of Caretta caretta in the North Adriatic Sea: relevant gross and histological lesions.
No full textAPPLICATION OF MINI-FLOTAC TECHNIQUE TO SEA TURTLES FECAL SAMPLES: EVALUATION OF SENSITIVITY AND COMPARISON WITH A TRADITIONAL COPROMICROSCOPIC METHOD
Full text linkQualitative and quantitative methods for estimating Spirorchiidiasis burden in sea turtles
Full text linkInfection by blood flukes Hapalotrema mistroides and Neospirorchis sp. (Digenea: Spirorchiidae) has been recently reported in Caretta caretta (Linnaeus, 1758) in the Mediterranean Sea. Observations of post mortem lesions are generally used to assess disease severity, and few attempts have been made to standardize the evaluation of the parasitic burden from tissue egg counts. Faeces and spleen homogenates of 105 loggerheads from the northwestern Adriatic Sea were submitted to a sedimentation-flotation technique for the research of spirorchiid eggs; molecular techniques were used for unequivocal identification. Egg quantification for positive faeces and spleen samples was achieved using a modified McMaster method. Spleen samples were also submitted to quantification through the only method cited in the literature for similar purposes, which involves preventive chemical digestion. Correlations between splenic counts obtained from the two different methods and between faecal and splenic egg burdens were calculated using Spearman's rho test. Concordance between studies on eggs in faeces and spleen tissue was also calculated. Eggs of H. mistroides and Neogen-11 were found in spleen and faecal samples. Strong correlations were found between splenic egg burdens calculated from the two methods for H. mistroides, demonstrating that the modified McMaster method can be used for quantification. A multiplying factor must be used before drawing comparisons, as egg burdens are higher in value when measured after chemical digestion. High concordance was obtained from a qualitative examination of faeces and spleen tissue of H. mistroides, showing that copromicroscopic examination can be used for in vivo diagnosis. As weak correlations were found between faecal and splenic egg counts, faecal burden cannot be regarded as indicative of disease severity. For Neogen-11, low concordance was found between faeces and spleen tissue, likely reflecting lower levels of egg embolization in organs
Comparing pooled and individual samples for estimation of gastrointestinal strongyles burden and treatment efficacy in small ruminants
Full text linkMonitoring endoparasite burden (FEC) and treatment efficacy (FECR) is a key element of sustainable parasite control. However, the costs of the analysis often discourage their implementation by farmers and veterinary practitioners. Pooling samples is considered to be a good alternative to reduce time and monetary costs, but limited data are available on the use of pooled samples in small ruminants, especially for goats. In this study, data collected over the years in sheep and goat farms were analyzed, and results obtained from individual and pooled analysis were compared for the purposes of FEC and FECR assessment. A total of 801 individual and 134 pooled samples (composed of 3-12 individual samples) were included. For FECR testing, 2 pools of 5 samples each were created per trial and the same animals were sampled at day 0 (D0 - treatment day) and 14 days after (D14). Samples were analyzed by McMaster technique (limit of detection 20 EPG). Results from pooled and individual FEC were not significantly different (Wilcoxon signed-rank test) and correlation (Spearman's rank test) was high for all sub-categories, although agreement (Lin's concordance correlation) was often classified as poor. Results were not influenced by the pool size (= 6). Interpretation of treatment efficacy between the two methods was comparable for all sheep trials, while it differed for goats in 4 out of 10 trials. Wilcoxon signed-rank test indicated a non significant difference between pooled and individual FECR. However, correlation and agreement between FECR were considerably better for sheep compared to goats, for which they were very limited, despite the correlation between FEC at D0 and D14 was always high. According to our results, pooled FECR can be a good option but the absence of 95 %CI represents a major drawbacks in the interpretation of results. Further studies on the topic for goats are needed
CRASSICAUDOSIS IN FIN WHALES (BALAENOPTERA PHYSALUS) STRANDED ALONG ITALIAN COASTS
No full textOf several known crassicaudid infections, those caused by Crassicauda boopis (Nematoda, Spirurida) in whale are especially pathogenic. The giant adult nematode grows in the vascular and ureteral system of the kidney; it can cause complete vascular occlusion and kidney failure as described in Atlantic fin whales, Balaenoptera physalus; no data are still available in literature for this host species in Mediterranean basin. Six fin whales, stranded dead along Italian coastline in the period 2006-2013, were analyzed for Crassicauda infection. The parasites were morphologically identified according to Lambertsen (1985); molecular analyses by amplification and sequencing of a portion of the 18S of the small subunit ribosomal and internal transcribed spacers 2 (ITS2) of the rRNA were carried out. Formalin-fixed tissues were routinely processed for histology. Crassicaudosis was observed in four out six examined animals. Adult C. boopis were found in three fin whales, one of which had also nematode larvae in intestinal nodules and mesenteric vessels’ wall. Another animal showed vascular lesions with ruined fragments of the nematode inside. The sequences obtained from the parasitic elements (adults, larvae and lesions) showed a high identity with each other for ITS2 region; the 18S sequences had high identity with the unique Crassicauda sequence (C. magna) registered in GenBank (Accession number: KM233410.1). Chronic vasculitis and/or thrombosis were observed in renal vessels, vena cava and mesenteric arteries, leading to almost complete occlusion of vessels lumen in three cases. Histology showed renal fibrosis, perirenal granulomas and disseminated Crassicauda eggs in renal vessels, renal pelvis and adrenal glands. This study provides data on the presence, pathology and biomolecular characterization of C. boopis in fin whale of the Mediterranean Sea
FIRST REPORT OF GENUS NEOSPIRORCHIS IN SEA TURTLES FROM THE MEDITERRANEAN SEA
No full textSpirorchiid flukes (Digenea: Spirorchiidae) are parasites of circulatory system of freshwater and sea turtles. The presence of adults in heart and vessels and the spreading of eggs to various organs can lead to severe vasculitis, thrombosis and development of disseminated granulomas. Neospirorchis sp. in particular has been associated to meningitis and mortality mass event because of its tropism for Central Nervous System (CNS). One hundred forty-four carcasses of loggerhead turtle (Caretta caretta), stranded along NorthEastern coast of Adriatic sea in the period 2009-2015 were analyzed for spirorchidiasis. After necropsies, research of parasitic elements by stereomicroscopy in major vessels and organs was performed, followed by copromicroscopic analysis and histological examination of tissues. Internal transcribed spacer 2 region (ITS2) from parasitic elements was amplified and sequenced for comparison with data in literature. Neospirorchis eggs (Type 3) were identified in faecal samples of six turtles (4.16%); four out of these had a mixed infection with Hapalotrema. No adults of Neospirorchis were found. Type 3 egg masses were grossly visible as black short stripes on the intestinal mucosa; big clusters of rounded eggs surrounded by granulomatous inflammation were histologically visible in mucosal and submucosal layers. Small granulomas surrounding isolated spirorchiid eggs were ubiquitous in several organs, but not in CNS. ITS2 sequences obtained from isolated eggs matched (100% identity) with those of Neospirorchis (Neogen11) described by Stacy (2008). To identify the possible origin of the infected turtles, sequences of mtDNA encompassing the Dloop region were analyzed. All turtles were carriers of Mediterranean haplotypes. This represents the first report of genus Neospirorchis in C. caretta living in the Mediterranean Sea. In this study spirorchidiasis seems not to have severely affected health status of the host, being lesions always mild in all districts
COMPARISON BETWEEN MINI-FLOTAC AND A CONVENTIONAL TECHNIQUE FOR THE DETECTION OF HELMINTH EGGS IN CETACEAN STOOL SAMPLES
Full text linkUpdates on Ecology and Life Cycle of Sulcascaris sulcata (Nematoda: Anisakidae) in Mediterranean Grounds: Molecular Identification of Larvae Infecting Edible Scallops
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