ABSTRACT
Anthropogenic pollution poses a threat to marine conservation by causing chronic toxic effects. Seabirds have contact throughout their lives with pollutants like plastic, metals, polychlorinated biphenyls (PCBs), and organochlorine pesticides such as hexachlorocyclohexanes (HCHs). We assessed 155 Manx shearwaters (Puffinus puffinus) stranded along the Brazilian coast, analyzing associations between organic pollutants, plastic ingestion, biomarkers (transcript levels of aryl hydrocarbon receptor, cytochrome P450-1A-5 [CYP1A5], UDP-glucuronosyl-transferase [UGT1], estrogen receptor alpha-1 [ESR1], and heat shock protein-70 genes) and enzymes activity (ethoxy-resorufin O-deethylase and glutathione S-transferase [GST]). Plastic debris was found in 29 % of the birds. The transcription of UGT1 and CYP1A5 was significantly associated with hexachlorobenzene (HCB) and PCBs levels. ESR1 was associated with HCB and Mirex, and GST was associated with Drins and Mirex. While organic pollutants affected shearwaters more than plastic ingestion, reducing plastic availability remains relevant as xenobiotics are also potentially adsorbed onto plastics.
Subject(s)
Biomarkers , Environmental Monitoring , Polychlorinated Biphenyls , Water Pollutants, Chemical , Animals , Biomarkers/metabolism , Water Pollutants, Chemical/toxicity , Birds , Glutathione Transferase/metabolism , Brazil , Plastics , Cytochrome P-450 CYP1A1/metabolism , Cytochrome P-450 CYP1A1/genetics , Pesticides/toxicity , Glucuronosyltransferase/metabolism , Glucuronosyltransferase/genetics , Receptors, Aryl Hydrocarbon/metabolismABSTRACT
We report full-genome characterization of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus from an outbreak among sea lions (August 2023) in Argentina and possible spillover to fur seals and terns. Mammalian adaptation mutations in virus isolated from marine mammals and a human in Chile were detected in mammalian and avian hosts.
Subject(s)
Influenza A Virus, H5N1 Subtype , Influenza A virus , Influenza in Birds , Animals , Humans , Influenza in Birds/epidemiology , Argentina/epidemiology , Birds , Disease Outbreaks , Phylogeny , MammalsABSTRACT
Fibropapillomatosis (FP) is a disease characterized by epithelial tumors that can impede life-sustaining activities of sea turtles, especially green turtles (Chelonia mydas). FP is caused by a herpesvirus, but environmental factors are also thought to play a role in triggering FP tumor growth. In this study, we evaluate the epidemiology of FP tumors in green turtles along the coast of Espírito Santo, Brazil, a region where juvenile green turtles are known to aggregate with high FP prevalence. A dataset comprising 2024 beach-cast green turtles recorded through daily beach surveys on 400 km of coastline from 2018 to 2021 (inclusive) was evaluated. FP tumors were recorded in 40.9% of the individuals in this dataset, and presence of FP tumors was predicted by individual variables (presence of marine leeches, stranding code, curved carapace length, body mass-size residual) and characteristics of the stranding site (distance to nearest metallurgical plant, mean sea surface salinity (SSS), annual range of sea surface temperature (SST)). Additionally, a second dataset comprising detailed information about the size and anatomical distribution of tumors in 271 green turtles with FP from the same region was evaluated. Hierarchical clustering analysis revealed these turtles could be classified in three groups according to the anatomical distribution of their tumors, and in turn the group to which each turtle was assigned could be predicted by the study period (2010-2014 vs. 2018-2022) and by characteristics of the stranding/capture site (green turtle stranding density, mean sea surface chlorophyll-a concentration, mean SSS, mean SST, annual range of SST). These results corroborate that individual and environmental factors play a significant role driving FP epidemiology. Furthermore, the results suggest that rather than behaving as a single entity, FP may be seen as a mosaic of distinct anatomical patterns that are not necessarily driven by the same environmental factors.
Subject(s)
Carcinoma , Turtles , Animals , Brazil/epidemiology , Animal Shells , Body SizeABSTRACT
Plastic ingestion is a problem for seabirds worldwide. In addition to direct health effects such as obstruction or perforation of the gastrointestinal tract, plastic ingestion can also lead to indirect health effects through the release of chemicals that may be absorbed and cause systemic and chronic toxicity. Among chemicals that can be released by plastics are phthalate esters, a group of chemicals widely used as plasticizers or additives to change the physical characteristics of plastics. In this study, three phthalate esters, dimethyl phthalate (DMP), dibuthyl phthalate (DBP), and diethylhexyl phthalate (DEHP), were quantified in the uropygial gland of 48 seabirds from 16 species collected ashore in a tropical region, the coast of Espírito Santo, Eastern Brazil. Including trace levels, DMP was detected in 16 birds (33%) from 10 species, with an average concentration of 0.014 ± 0.005 ng/µl (mean ± SD for individuals with concentrations above the practical level of detection of 0.01 ng/µl). DBP was detected in 15 birds (31%) from 11 species, with an average concentration of 0.049 ± 0.032 ng/µl. DEHP was detected in 21 birds (44%) from 11 species, with an average concentration of 0.115 ± 0.105 ng/µl. DMP concentration in the uropygial gland was positively associated with the presence, number, and mass of plastic items in the upper digestive tract. However, no such relationship was noted for DBP nor DEHP, suggesting the concentration of phthalate compounds in the uropygial gland might not always serve as a reliable proxy for plastic ingestion. In spite of relatively high frequencies of detection, the low concentrations of phthalates detected in this study suggest levels of exposure below known toxicity thresholds. Further studies on the potential adverse effects of phthalate exposure in seabirds are necessary, especially on the reproductive development of embryos and chicks.
Subject(s)
Diethylhexyl Phthalate , Plastics , Animals , Plasticizers , Esters , Brazil , Chickens , EatingABSTRACT
BACKGROUND AND AIMS: Penguins are seabirds that manifest physiological and immunological alterations during the reproductive season. The objectives of this study were to evaluate the laboratory parameters of male and female Magellanic penguins and to determine the penguins' hematological response to homeopathic medicines during that reproductive period. METHODS: Penguins (N = 18), kept under human care in a zoological park setting, were evaluated during the reproductive period and were divided randomly into two groups: a group subjected to treatment with Echinacea angustifolia 6cH and Avena sativa 6cH (N = 8; four breeding couples), and a placebo control group (N = 10; five breeding couples). The investigators were blinded to treatment allocation. Two-way ANOVA was performed to determine whether the experimental group (control or verum) and the sex of the animal had any significant effect on the variation of each hematological parameter between the samples. One-way ANOVA was performed on hematological parameters for which the sex did not present a significant effect. The significance level was p ≤0.05. RESULTS: Significant effects were seen regarding the following: mean corpuscular volume (MCV), in which the verum group showed an increase (29.78 ± 52.95 fL) while the control group showed stability/reduction (-3.08 ± 46.36 fL) (p = 0.049); proportion of heterophils, in which the verum group showed a less marked increase (8.38 ± 12.53%) than that of the control group (18.00 ± 9.37%) (p = 0.010); lymphocyte concentration, in which the verum group showed less marked reduction (-4.39 ± 2.21 × 109 cells/L) than that of the control group (-1.56 ± 2.76 × 109 cells/L) (p = 0.001); and proportion of lymphocytes, in which the verum group showed a less marked reduction (-6.75 ± 10.35%) than that of the control group (-17.3 ± 8.73%) (p = 0.002). CONCLUSION: Comparison of samples collected before and during the reproductive period showed that, regardless of group allocation, there were differences in the effects on MCV, heterophils and lymphocytes. Treatment with Echinacea angustifolia and Avena sativa resulted in maintenance of lymphocyte levels in Magellanic penguins during the breeding period, thus aiding these birds' immunity.
Subject(s)
Echinacea , Homeopathy , Spheniscidae , Animals , Female , Male , Avena , Reproduction , Spheniscidae/physiologyABSTRACT
Sarcoptic mange epidemics can devastate wildlife populations. In 2014, mange was first detected in vicuñas (Vicugna vicugna) and guanacos (Lama guanicoe) in San Guillermo National Park (SGNP), Argentina. This study describes the temporal dynamics of the outbreak, its effects on the park's wild camelid populations between 2017-2019, and investigates the potential source of the epidemic. From May 2017 to June 2018, transect surveys indicated a sharp decrease in the density of living vicuñas and guanacos by 68% and 77%, respectively. By April 2019 no vicuñas or guanacos were recorded on transect surveys, suggesting their near-extinction in the park. Clinical signs consistent with mange (e.g., intense scratching, hyperkeratosis, alopecia) were observed in 24% of living vicuñas (n = 478) and 33% of living guanacos (n = 12) during surveys, as well as in 94% of vicuña carcasses (n = 124) and 85% of guanaco carcasses (n = 20) examined. Sarcoptes scabiei was identified as the causal agent by skin scrapings, and the cutaneous lesions were characterized by histopathology (n = 15). Genetic characterization revealed that mites recovered from seven vicuñas (n = 13) and three guanacos (n = 11) shared the same genotype, which is consistent with a single source and recent origin of the epidemic. Tracing the potential source, we identified a governmental livestock incentive program which introduced llamas (Lama glama) in areas adjacent to SGNP in 2009, some of which had alopecic scaling consistent with sarcoptic mange. Though at the time of our study no llamas with mange were available for confirmatory sampling, we hypothesize that the introduction of mange-infected llamas may have triggered the outbreak in wild camelids. This unprecedented event in SGNP had devastating effects on dominating herbivores with potentially profound cascading effects at the community and ecosystem levels.
Subject(s)
Parks, RecreationalABSTRACT
Espírito Santo state is located on the eastern margin of Brazil, in a transitional tropical-subtropical area (18°S-21°S) dominated by oligotrophic waters. With the exception of humpback whales (Megaptera novaeangliae), the cetacean community of Espírito Santo has been understudied. In addition to the chronic impacts from fisheries, marine pollution, urban development, and coastal habitat degradation, in November 2015 the cetacean communities of Espírito Santo were challenged by the greatest environmental disaster in Brazil's history. The Mariana dam disaster caused 60 million cubic meters of mining waste to be washed into the Doce River, which ultimately flowed to the coastal waters of Espírito Santo, with a high concentration of heavy metals. This study reviews and updates information on cetacean strandings in the state of Espírito Santo (excluding humpback whales) prior to this disaster. From 1975 to September 2015, there were 461 recorded cetacean strandings, representing 20 species. An average 1.18 strandings per 100 km per month were recorded since a state-wide daily beach survey program was implemented in October 2010, contrasting with the 0.14 strandings per 100 km per month in previous years. Six species comprised the majority (94.7%) of stranding events: Guiana dolphin (Sotalia guianensis), Franciscana (Pontoporia blainvillei), rough-toothed dolphin (Steno bredanensis), bottlenose dolphin (Tursiops truncatus), sperm whale (Physeter macrocephalus), and melon-headed whale (Peponocephala electra). Oceanic cetaceans stranded most frequently on the southern portion of Espírito Santo, where the continental platform is narrower, whereas the strandings of coastal cetaceans such as Guiana dolphins and Franciscanas were concentrated near estuaries, especially the Doce River. This is particularly concerning in face of the Mariana dam disaster, which drastically altered the estuarine and coastal environment associated with the Doce River.
ABSTRACT
This study reports the case of a Manx shearwater (Puffinus puffinus) that died from avian malaria while under care at a rehabilitation center in Espírito Santo, Brazil. The bird was rescued on October 2018, and remained under care until it died suddenly on January 2019. A blood smear produced 8 days before death was negative for parasites, whereas a blood smear produced post-mortem revealed a high parasitemia by a parasite resembling Plasmodium cathemerium. The sequence of a 412 bp segment of the cyt-b gene was identical to that of lineage PADOM09, and phylogenetic analysis corroborated that this parasite was closely-related to known lineages of P. cathemerium. The acuteness and severity of the infection documented in this case suggest that seabirds of the order Procellariiformes might be highly susceptible to Plasmodium infections, raising the concern that avian malaria may present a significant threat to their conservation.
Subject(s)
Birds , Malaria, Avian/diagnosis , Plasmodium/isolation & purification , Animals , Brazil , Malaria, Avian/parasitology , Plasmodium/classificationABSTRACT
Black lion tamarins (Leontopithecus chrysopygus) are endangered callithrichids. Their conservation may require future translocations or reintroductions; however these approaches involve risks of pathogen introduction in the environment and stress-related opportunistic infections in these animals. In order to screen for opportunistic and potential pathogenic bacterial and fungal microbiota, ten free-ranging and ten captive Black lion tamarins were studied and the results compared. Nasal, oral and rectal swabs were collected and cultured for aerobic and facultative anaerobic bacteria and fungi, and a total 203 bacterial and 84 fungal isolates were obtained. Overall, the most frequent organisms were Staphylococcus spp., Bacillus spp., Candida spp. and Aspergillus spp. Microbiota of free-ranging and captive animals were similar in composition. A number of potentially pathogenic organisms were identified, emphasizing the importance of microbiological screening in future translocation or reintroduction conservation management programs.
Subject(s)
Animals , Bacteria/classification , Fungi/classification , Leontopithecus/microbiology , Microbiota , Mouth/microbiology , Nasal Cavity/microbiology , Rectum/microbiology , Bacteria/growth & development , Bacteria/isolation & purification , Fungi/growth & development , Fungi/isolation & purification , Microbiological TechniquesABSTRACT
Black lion tamarins (Leontopithecus chrysopygus) are endangered callithrichids. Their conservation may require future translocations or reintroductions; however these approaches involve risks of pathogen introduction in the environment and stress-related opportunistic infections in these animals. In order to screen for opportunistic and potential pathogenic bacterial and fungal microbiota, ten free-ranging and ten captive Black lion tamarins were studied and the results compared. Nasal, oral and rectal swabs were collected and cultured for aerobic and facultative anaerobic bacteria and fungi, and a total 203 bacterial and 84 fungal isolates were obtained. Overall, the most frequent organisms were Staphylococcus spp., Bacillus spp., Candida spp. and Aspergillus spp. Microbiota of free-ranging and captive animals were similar in composition. A number of potentially pathogenic organisms were identified, emphasizing the importance of microbiological screening in future translocation or reintroduction conservation management programs.
Subject(s)
Animals , Bacteria/classification , Fungi/classification , Leontopithecus/microbiology , Microbiota , Mouth/microbiology , Nasal Cavity/microbiology , Rectum/microbiology , Bacteria/growth & development , Bacteria/isolation & purification , Fungi/growth & development , Fungi/isolation & purification , Microbiological TechniquesABSTRACT
Black lion tamarins (Leontopithecus chrysopygus) are endangered callithrichids. Their conservation may require future translocations or reintroductions; however these approaches involve risks of pathogen introduction in the environment and stress-related opportunistic infections in these animals. In order to screen for opportunistic and potential pathogenic bacterial and fungal microbiota, ten free-ranging and ten captive Black lion tamarins were studied and the results compared. Nasal, oral and rectal swabs were collected and cultured for aerobic and facultative anaerobic bacteria and fungi, and a total 203 bacterial and 84 fungal isolates were obtained. Overall, the most frequent organisms were Staphylococcus spp., Bacillus spp., Candida spp. and Aspergillus spp. Microbiota of free-ranging and captive animals were similar in composition. A number of potentially pathogenic organisms were identified, emphasizing the importance of microbiological screening in future translocation or reintroduction conservation management programs.
Subject(s)
Bacteria/classification , Fungi/classification , Leontopithecus/microbiology , Microbiota , Mouth/microbiology , Nasal Cavity/microbiology , Rectum/microbiology , Animals , Bacteria/growth & development , Bacteria/isolation & purification , Fungi/growth & development , Fungi/isolation & purification , Microbiological TechniquesABSTRACT
This study is the first report on mortality of Spheniscus magellanicus, penguin of South America, caused by Plasmodium tejerai, which was identified using morphological and molecular analyses. Blood stages (trophozoites, meronts and gametocytes) were reported and illustrated. The necropsy revealed marked splenomegaly and pulmonary edema, as well as moderate hepatomegaly and hydropericardium. The histopathology revealed the presence of tissue meronts in the macrophages and endothelial cells of multiple organs. The molecular analyses showed 5.6% of genetic divergence in cytochrome b gene between P. tejerai and Plasmodium relictum. Morphology of blood and tissue stages of P. tejerai is similar to P. relictum; the distinction between these two species requires experience in the identification of avian Plasmodium species. Molecular studies associated with reliably identified morphological species are useful for barcoding and comparisons with previous studies of wildlife malaria infections as well as for posterior phylogenetic and phylogeographic studies. S. magellanicus is a new host record of P. tejerai, which is the virulent parasite and worth more attention in avian conservation and veterinary medicine projects in South America.