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1.
PeerJ ; 12: e18117, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39399432

RESUMO

As sperm whales are important predators that control energy flux in the oceans, changes in their population can be used as a sentinel to measure of ecosystem health. The present study conducted a sperm whale survey of the eastern Midriff Islands Region in the Gulf of California over the course of nine years, recording sightings and collecting photographs of the fluke of sperm whale individuals. A photo-identification catalog was compiled, while individual recapture data were used to estimate the population size in the central portion of the Gulf of California, using a Jolly-Seber POPAN open population model. The results obtained show a yearly population of between 20 and 167 sperm whales, with a super population of 354 sperm whales observed between 2009 and 2015. However, from 2016 to 2018, no sightings of the species were recorded, which coincides with the decline observed in landings of their main prey, the jumbo squid, in the region. General additive model conducted on sperm whale sightings per unit of effort vs jumbo squid landings obtained an adjusted R2 of 0.644 and a deviance explained of 60.3%, indicating a good non-linear relationship between sightings of this odontocete and its prey availability. This evidence suggests that sperm whales departed the region between 2016 and 2018, due to a documented fishery collapse alongside changes of their main prey into its small phenotype, possibly as the result of increase warming conditions in surface and subsurface waters in the Gulf of California in the last three decades.


Assuntos
Decapodiformes , Cachalote , Animais , Cachalote/fisiologia , Decapodiformes/fisiologia , Dinâmica Populacional , Densidade Demográfica , Ecossistema , California
2.
Vet Ophthalmol ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39314123

RESUMO

OBJECTIVE: To describe morphological features of Megaptera novaeangliae eyes using ultrasonography and histology. ANIMAL STUDIED: A total of 21 globes from 19 M. novaeangliae were used for the study, including two animals with bilateral assessment. Nine stranded animals were found alive, 10 dead. PROCEDURES: Carcasses were classified according to decomposition state. Globes were assessed ultrasonographically, biometric measurements were taken and then the tissues were sectioned for histological analysis. RESULTS: Seventeen carcasses were classified as decomposition code 2 and two as code 3. Fifteen animals were calves, three juveniles and one adult, twelve males, and five females. The cornea was thinner in the center of the eye and thicker at the periphery. The lens had an oval shape. Fourteen animals showed a structure in the vitreous body which looked triangular and filamentous by ultrasonography and, histologically, originated in the central part of the optic nerve and extended to the posterior region of the lens, composed of connective tissue. The most common abnormalities found by ultrasonograph were retinal detachment (n = 13) and displacement of the lens into the vitreous (n = 4), along with alterations suggestive of hemorrhage, fibrin deposits, and increased echogenicity in the optic nerve (n = 2). CONCLUSIONS: An intraocular structure not previously described in cetaceans was found in this investigation; its function remains unknown. Circulatory changes that were evident in the histopathological analysis may be due to the stranding process and raise the need to consider ophthalmic examinations before reintroducing stranded mysticetes.

3.
Animals (Basel) ; 14(16)2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39199819

RESUMO

The study of dentition anomalies and pathologies in wildlife contributes, together with other indicators, to understanding the relevance of some factors on the health status of populations. This has not been properly evaluated in invasive mammals. To test the feasibility of eradication, the government of Tierra del Fuego performed the eradication of beavers (Castor canadensis) from 2016 to 2018: 1121 animals were removed and 970 examined. These beavers were examined to analyze the incidence of dentition anomalies and other dentition and cranial conditions. The beavers presented two dentition anomalies: hypodontia and hyperdontia (0.41% in both cases), and for the first time, a dentition anomaly in the upper quadrants was reported. Beavers also presented artifactual tooth loss (0.30%) and acquired tooth loss (0.61%) but with low incidence. The presence of fractured teeth (0.41%) and caries (0.31%) occurred in all age classes, also with low incidence. The third molar tooth was the most affected, showing a female bias. The 0.93% of skulls had a cranial abnormality represented as a buccal curvature. Malocclusion cases also were recorded (0.51%). The low prevalence of dentition anomalies, fractured teeth, caries, and cranial abnormalities would not compromise the lifespan of beavers. These results leave a precedent of dentition anomalies and dentition and cranial conditions in an invasive mammal.

4.
BMC Vet Res ; 20(1): 285, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956597

RESUMO

Clade 2.3.4.4b highly pathogenic avian influenza (HPAI) H5N1 virus was detected in the South American sea lions found dead in Santa Catarina, Brazil, in October 2023. Whole genome sequencing and comparative phylogenetic analysis were conducted to investigate the origin, genetic diversity, and zoonotic potentials of the H5N1 viruses. The H5N1 viruses belonged to the genotype B3.2 of clade 2.3.4.4b H5N1 virus, which was identified in North America and disseminated to South America. They have acquired new amino acid substitutions related to mammalian host affinity. Our study provides insights into the genetic landscape of HPAI H5N1 viruses in Brazil, highlighting the continuous evolutionary processes contributing to their possible adaptation to mammalian hosts.


Assuntos
Virus da Influenza A Subtipo H5N1 , Filogenia , Leões-Marinhos , Sequenciamento Completo do Genoma , Animais , Leões-Marinhos/virologia , Brasil , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/classificação , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/virologia , Genoma Viral , Genótipo , Variação Genética
5.
Animals (Basel) ; 14(14)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39061554

RESUMO

Candidiasis is a significant fungal infection caused by various species of the genus Candida, posing health challenges to a wide range of animals, including Choloepus species (two-toed sloths). This review article aims to provide a comprehensive understanding of candidiasis in Choloepus sp., highlighting the etiology, epidemiology, pathogenesis, clinical manifestations, diagnosis, treatment, and prevention strategies. This article begins by examining the causative agents, primarily focusing on Candida albicans, which is the most commonly implicated species in candidiasis. The epidemiological aspects are discussed, emphasizing the prevalence of candidiasis in wild and captive Choloepus populations and identifying predisposing factors, such as immunosuppression, stress, poor nutrition, and environmental conditions. Pathogenesis is explored, detailing the mechanisms through which Candida species invade host tissues and evade immune responses. Clinical manifestations in Choloepus sp. are described, including oral thrush, cutaneous lesions, and gastrointestinal infections, and their impact on the health and behavior of affected individuals. Diagnostic methods, including culture techniques, histopathology, and molecular assays, are reviewed to highlight their roles in accurately identifying Candida infections. This article also covers treatment options, focusing on antifungal therapies and supportive care tailored to the unique physiology of Choloepus sp. Finally, prevention and management strategies are discussed, emphasizing the importance of maintaining optimal husbandry practices, regular health monitoring, and early intervention to reduce the incidence and impact of candidiasis in Choloepus populations. This review underscores the need for further research to enhance our understanding of candidiasis and improve health outcomes for these unique and vulnerable animals.

6.
Emerg Infect Dis ; 30(6): 1296-1298, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781986

RESUMO

Cetacean morbillivirus is an etiologic agent associated with strandings of live and dead cetacean species occurring sporadically or as epizootics worldwide. We report 2 cases of cetacean morbillivirus in humpback whales (Megaptera novaeangliae) in Brazil and describe the anatomopathological, immunohistochemical, and molecular characterization findings in the specimens.


Assuntos
Jubarte , Infecções por Morbillivirus , Morbillivirus , Filogenia , Animais , Morbillivirus/isolamento & purificação , Morbillivirus/genética , Morbillivirus/classificação , Brasil , Infecções por Morbillivirus/veterinária
7.
Parasitol Res ; 123(5): 200, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696061

RESUMO

The humpback whale (Megaptera novaeangliae) is a cosmopolitan migratory, seasonal mysticete that frequents the Brazilian coast. Strands of specimens may occur during the migratory stay in the country. In 2021 and 2022, three live humpback whales stranded on the coast of Rio Grande do Sul and Santa Catarina states in southern Brazil. After euthanasia, specimens were necropsied, and organs were thoroughly examined for lesions. Grossly, in all three cases, the liver exhibited multifocal, irregular, firm, white areas on the hepatic capsule, which extended into the parenchyma. On the cut surface, the livers were yellow to pale brown with orangish to greenish areas, the bile ducts were prominent, thickened, and severely dilated, and leaf-shaped flukes were found inside of them. Additionally, one case showed moderate atrophy of the right hepatic lobe. The histological findings included dilation of bile ducts, hyperplasia of the bile duct epithelium, marked inflammatory infiltration of lymphocytes, plasma cells, and eosinophils, and portal fibrosis. The parasite Brachycladium goliath was both morphologically and molecularly identified based on diagnostic key for trematodes and the original description of the species, and the amplification and sequencing of the ITS-2 region, respectively. Even though hepatic injury was not the primary cause of stranding, it may have contributed to the debilitation of the whales. To the authors' knowledge, this is the first study that reports M. novaeangliae as a definitive host of B. goliath and that describes the lesions caused by the parasite in cetaceans.


Assuntos
Jubarte , Fígado , Trematódeos , Infecções por Trematódeos , Animais , Jubarte/parasitologia , Brasil , Trematódeos/classificação , Trematódeos/anatomia & histologia , Trematódeos/isolamento & purificação , Trematódeos/genética , Fígado/parasitologia , Fígado/patologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Filogenia , Masculino
8.
Virus Evol ; 10(1): veae031, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756986

RESUMO

The highly pathogenic avian influenza viruses of clade 2.3.4.4b have caused unprecedented deaths in South American wild birds, poultry, and marine mammals. In September 2023, pinnipeds and seabirds appeared dead on the Uruguayan Atlantic coast. Sixteen influenza virus strains were characterized by real-time reverse transcription PCR and genome sequencing in samples from sea lions (Otaria flavescens), fur seals (Arctocephalus australis), and terns (Sterna hirundinacea). Phylogenetic and ancestral reconstruction analysis showed that these strains have pinnipeds most likely as the ancestral host, representing a recent introduction of clade 2.3.4.4b in Uruguay. The Uruguayan and closely related strains from Peru (sea lions) and Chile (sea lions and a human case) carry mammalian adaptative residues 591K and 701N in the viral polymerase basic protein 2 (PB2). Our findings suggest that clade 2.3.4.4b strains in South America may have spread from mammals to mammals and seabirds, revealing a new transmission route.

9.
J Med Entomol ; 61(4): 1026-1030, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38616043

RESUMO

Ehrlichia chaffeensis is a bacterium belonging to the Anaplasmataceae family. In Mexico, only 2 species have been recorded in association with tick species and humans. The objective of the present study was to detect the presence of bacteria of the genus Ehrlichia in ticks collected from the Chamela-Cuixmala Biosphere Reserve, Jalisco, Mexico. The collected ticks were identified and analyzed individually by polymerase chain reaction to amplify a fragment of the Anaplasmataceae 16S rRNA gene and the Ehrlichia-specific dsb gene. A total of 204 ticks, corresponding to 5 species of Ixodidae and 1 of Argasidae, were collected from 147 mammals of 6 species and 4 orders; 57 ticks collected from vegetation were also included. Among the total ticks collected, 1.47% (3/204) was positive for Ehrlichia sp. DNA was obtained using the primers EHR 16SD and EHR 16SR for 16S rRNA and DSB-330 and DSB-728 for dsb. The positive samples corresponded to a larva (Amblyomma sp.) associated with Didelphis virginiana and 2 nymphs (Amblyomma cf. oblongoguttatum) infesting Nasua narica. None of the ticks collected from the vegetation tested positive for Ehrlichia sp. DNA on the basis of the 16S rRNA and dsb genes. The sequences from the larvae of Amblyomma sp. and the nymphs of A. cf. oblongoguttatum were similar to those of E. chaffeensis. The phylogenetic analysis inferred with maximum likelihood corroborated the identity as E. chaffeensis. Although the role of these tick species as vectors of E. chaffeensis is still undetermined, the presence of infected ticks in the area indicates a potential zoonotic risk.


Assuntos
Amblyomma , Ehrlichia chaffeensis , México , Animais , Ehrlichia chaffeensis/isolamento & purificação , Ehrlichia chaffeensis/genética , Amblyomma/microbiologia , Ehrlichiose/transmissão , Ehrlichiose/microbiologia , RNA Ribossômico 16S/análise , Florestas , Vetores Aracnídeos/microbiologia , Ninfa/microbiologia , Ninfa/crescimento & desenvolvimento , Feminino , Ixodidae/microbiologia , Humanos
10.
PeerJ ; 12: e17244, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590704

RESUMO

Nocturnal activity of tropical otters is rarely reported. To date no studies have documented den use by sympatric giant (Pteronura brasiliensis) and neotropical otters (Lontra longicaudis). We used camera-traps to monitor den use by sympatric otters along an equatorial Amazonian river. Camera-traps provided evidence that giant otters were more nocturnal around dens than sympatric neotropical otters. Nocturnal activity was recorded in 11% of giant otter photos (n = 14 of 125 photos), but was recorded only once for neotropical otters. Den use by giant and neotropical otters overlapped spatially and temporally but not concurrently. We hypothesize that previously reported nocturnal activity in neotropical otters is facilitated by the absence or low density of giant otters. Our results also underscore the need to use complementary techniques together with den counts for monitoring otters as sympatric species can use the same dens.


Assuntos
Carnívoros , Lontras , Animais , Simpatria , Rios
11.
J Environ Manage ; 351: 119815, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38100861

RESUMO

Although the marine megafauna often strands on beaches around the world, such as sea turtles and whales, stranding data are poorly managed and incorporated into management and conservation strategies. Here we use a knowledge value chain framework to call attention for the urgent need to improve our data architecture and knowledge management on marine megafauna strandings. We use Brazil, a continental megadiverse federative republic, as study model. After describing the main components and identifying the strengths and weaknesses of the current Brazilian data architecture, we propose 10 practical measures for its improvement involving researchers, companies, non-governmental organizations, legislators, policy makers, public agents, citizen scientists, and local communities. Although Brazil has notable strengths such as comprehensive environmental legislation, hundreds of scientists and dozens of prestigious research institutions, stranding data is not translated into technical-scientific knowledge; technical-scientific knowledge is not transformed into effective public regulations; deficient regulations lead to bad decisions and limited actions, which in turn result in ineffective management and conservation strategies. In light of the UN Decade of Ocean Science for Sustainable Development (2021-2030), we propose (1) expanding standardized beach monitoring projects to the entire Brazilian coast; (2) creating a governmental database with FAIR principles; (3) encouraging the development of broad citizen science initiatives; (4) funding scientists and research institutions; (5) boosting outreach activities among researchers to popularize the scientific knowledge; (6) raising awareness among legislators and policy makers on the problem of strandings; (7) updating the existing legal provisions on the environmental licensing of activities developed at sea; (8) hiring new environmental analysts and inspectors and improving the infrastructure of executing environmental agencies; (9) strengthening existing conservation networks with multiple stakeholders; and (10) making the results of the management and conservation strategies broadly accessible to society. These recommendations may also apply to other coastal countries around the world.


Assuntos
Gestão do Conhecimento , Organizações , Desenvolvimento Sustentável , Brasil
12.
Animals (Basel) ; 13(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38136800

RESUMO

Cetaceans are well known for their unique behavioral habits, such as calls and tactics. The possibility that these are acquired through social learning continues to be explored. This study investigates the ability of a young beluga whale to imitate novel behaviors. Using a do-as-other-does paradigm, the subject observed the performance of a conspecific demonstrator involving familiar and novel behaviors. The subject: (1) learned a specific 'copy' command; (2) copied 100% of the demonstrator's familiar behaviors and accurately reproduced two out of three novel actions; (3) achieved full matches on the first trial for a subset of familiar behaviors; and (4) demonstrated proficiency in coping with each familiar behavior as well as the two novel behaviors. This study provides the first experimental evidence of a beluga whale's ability to imitate novel intransitive (non-object-oriented) body movements on command. These results contribute to our understanding of the remarkable ability of cetaceans, including dolphins, orcas, and now beluga whales, to engage in multimodal imitation involving sounds and movements. This ability, rarely documented in non-human animals, has significant implications for the development of survival strategies, such as the acquisition of knowledge about natal philopatry, migration routes, and traditional feeding areas, among these marine mammals.

13.
PeerJ ; 11: e15742, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492398

RESUMO

Background: Previous studies suggest coexistence between sympatric neotropical (Lontra longicaudis) and giant otters (Pteronura brasiliensis) maybe facilitated by temporal and spatial differences in activity. Yet, to date there has been no systematic evaluation of activity of these species in sympatry. Here we use extensive multi-year field data to compare temporal and spatial patterns in the diurnal activity of sympatric giant and neotropical otters to answer three questions: Do temporal patterns in daytime river use change in relation to seasonal river levels (low, rising, high and declining river levels), do they change due to human disturbances (boats and fishing nets) and do patterns in neotropical otter activity change due to the presence of the larger sized giant otter? Methods: Direct observations of both species were recorded using standardized boat surveys along 218 km of rivers over 53 months during nine years (2011-2013 and 2015-2020). Complementary techniques (Generalized Additive Models, Kernel density estimates and non-parametric tests,) were used to compare diurnal activity patterns along rivers subdivided into 41 river reaches. Results: The presence of giant otters decreased threefold from 67% of the least disturbed reaches (few boats no fishing nets) to 18% of the most disturbed reaches with many boats and fishing nets. In contrast neotropical otter presence nearly doubled from 44% of the least disturbed to 73% of the most disturbed reaches with fewest giant otter detections. Both species were observed across all daytime hours but were observed rarely on the same day. There was no evidence to suggest simultaneous use of the same reach. When species were detected on the same day, they were separated spatially (median distance between species 12.5 km) and temporally (median time difference 3.0 hours). There was little change in activity of either species among seasons. Giant otters were less active in river reaches with fishing nets and boat use, whereas neotropical otter activity did not appear to be strongly affected by these activities. Conclusions: Our findings support evidence that diurnal activity in both otter species is flexible, with daytime activity changing due to human disturbances in the case of giant otters.


Assuntos
Lontras , Animais , Humanos , Rios , Simpatria , Estações do Ano
14.
Acta Trop ; 237: 106740, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36332674

RESUMO

THE FAMILY TRICHECHIDAE (ORDER SIRENIA) COMPRISES THREE SPECIES: African (Trichechus senegalenses), West Indian (T. manatus), WIM)], and the Amazonian manatees (T. inunguis, AMM). Whereas WIM inhabits both riverine and coastal systems in the western Atlantic, AMM is the only exclusively freshwater sirenian, endemic to the Amazon River Basin. The study of infectious agents is essential to species conservation, especially considering that both species are classified as Vulnerable by the IUCN Red List and as Endangered by the Brazilian Red List. The current knowledge about viral agents in sirenians is scarce. Herpesviruses and adenovirus are DNA viruses able to infect and cause disease in a wide range of hosts. Herein, we used panPCR protocols to survey herpesvirus and adenovirus in blood samples of wild WIM (n = 23) and AMM (n = 26) under human care in Brazil. Herpesvirus DNA was detected in one juvenile female WIM (1/23; 4.3%; 95% CI -4.7 - 13.3) from Ceará state and in four AMM (two juvenile females, a juvenile male, and an adult female; 4/26; 15.4%; 95% CI 0.5 - 30.3) from Amazonas state. The two different gammaherpesvirus DNA polymerase sequence types identified (one per species, a sequence type in a WIM and another one in three AMM) were highly similar (99% nucleotide identity) to Trichechid herpesvirus 1, reported in West Indian manatees of Florida (USA), and 100% identical when translated into amino acids. A herpesviral glycoprotein B sequence was identified in two AMM. None of the samples was positive to adenovirus. To the authors' knowledge, this is the first herpesvirus detection in manatees from South America, expanding the herpesvirus geographical range, and the first in WIM and AMM worldwide. Our findings suggest (i) that West Indian and Amazonian manatees are possibly the natural hosts of the detected herpesvirus, and (ii) coevolution of that gammaherpesvirus with Trichechus. Future studies are necessary to characterize the obtained virus and elucidate potential pathological effects (if any) in these species.


Assuntos
Herpesviridae , Trichechus inunguis , Trichechus manatus , Animais , Humanos , Feminino , Masculino , Trichechus inunguis/genética , Brasil/epidemiologia , Adenoviridae/genética , Trichechus , Herpesviridae/genética
15.
Pap. avulsos zool ; 63: e202363022, 2023. tab, graf, mapas, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1448755

RESUMO

Fire might occur under natural conditions in the Pantanal of Brazil; however, with climate change, severe periods of drought potentiated the devasting fires in 2020, resulting in substantial wildlife loss. Considering that mammal communities are strongly affected by fire and habitat alterations, the aim of this study was to evaluate possible differences in mammal diversity and the number of records before and one year after the fire in one region of the Pantanal of Mato Grosso, Brazil (Parque SESC Baía das Pedras - PSBP). The data collection was performed using camera trapping between 2015 and 2017 and 2021, together with visual field observations in PSBP. We observed that the mammal assemblage composition was similar before and one year after the fire. Four species were more or less frequent in burned areas than in unburned ones. Since the fire was controlled in this area, avoiding its total destruction, and the species that fled from the surrounding areas, which were completely burnt, might be using PSBP as a refuge while the vegetation recovers elsewhere. Therefore, the PSBP might have contributed to protecting mammal species after the fire and maintaining and conserving biodiversity on a regional scale in the Pantanal of Mato Grosso, Brazil.


Assuntos
Animais , Biodiversidade , Áreas Alagadas , Incêndios , Mamíferos/classificação
16.
Rev. bras. zootec ; 52: e20210199, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1436809

RESUMO

This experiment was conducted to investigate the effects of lactic acid bacteria preparations on microbial diversity and community structure of calves. On days 1 and 7 of the trial period, feces were collected into sterile tubes and labeled (Day 1: control group D1DZ, experimental group D1SY, and Day 7: control group D7DZ, experimental group D7SY). Twenty Angus calves (150±10 kg) were selected and randomly divided into two groups of 10 calves each. The control group fed a basal diet. In addition to feeding the basal diet, the experimental group was given 15 mL lactobacillus preparation orally at 09:00 and 16:00 h every day. Calves were allowed free feeding and drinking water. All other feeding environments and management conditions remained consistent with the experiment lasting for seven days. At the end of the experiment, the fecal microflora of the calves was analyzed using 16S rRNA sequencing techniques. The 16S rRNA analysis data were processed using the Excel 2007 software and analyzed by the IBM SPSS statistical software (Statistical Analysis System, version 22). The Alpha diversity index analysis showed that the Chao and the Ace indices were significantly different after feeding supplemented with lactic acid bacteria. The PCA analysis showed that the fecal flora structure differed significantly after supplementation with the lactic acid bacteria preparation. Further analysis showed that the lactic acid bacteria increased Firmicutes, Patescibacteria, Rikenellaceae_RC9_gut_group, Clostridium_sensu_stricto_1, and prevotellaceae_UCG-003 in the feces. Therefore, we speculate that lactic acid bacteria preparations play an important role in animal production and are beneficial to the diversity of the fecal microflora of the calves.


Assuntos
Animais , Bovinos , Suplementos Nutricionais , Dieta/veterinária , Fezes/microbiologia
17.
Microb Pathog ; 173(Pt A): 105800, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36309181

RESUMO

Few studies have analyzed the indicators of oxidative stress in marine mammals following exposure to lipopolysaccharides (LPS); sex and maturity-related differences have not been explored. The objective of this study was to compare the indicators of oxidative stress following exposure to LPS for 24 and 48 h in isolated Pacific bottlenose dolphin (Tursiops truncatus; N = 12) leukocytes in relation to sex and maturity stage, using spectrophotometry. Following 48 h under experimental conditions (10 µg LPS mL-1), the leukocytes from males (n = 5) produced significantly more superoxide radical (O2•-; F (1, 8) = 13.965, p = 0.006) and displayed significantly greater activities of catalase (CAT; F (1, 8) = 9.465, p = 0.015) and glutathione S-transferase (GST; p = 0.028) compared to the leukocytes from females (n = 7). Following 48 h under experimental conditions, maturity-stage did not significantly influence the indicators of oxidative stress. Mature bottlenose dolphins (n = 7) had a significantly higher average daily dietary intake compared to immature bottlenose dolphins (n = 5; F (1, 10) = 5.825, p = 0.036). These results suggest that sex-related strategies for coping with a proinflammatory challenge may be present within the leukocytes from bottlenose dolphins, while potential maturity stage-related strategies require further investigation.


Assuntos
Golfinho Nariz-de-Garrafa , Animais , Masculino , Feminino , Lipopolissacarídeos , Leucócitos , Estresse Oxidativo
18.
Adv Colloid Interface Sci ; 307: 102746, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35969965

RESUMO

Pharmaceutical nanotechnology has become a trend with incalculable advantages in the applicability of systems in the controlled, safe and effective release of drugs. Among the nanotechnological nanoparticles, the mesoporous silica nanoparticles stand out, a system with significant biocompatibility, good physical chemical stability, greater surface contact area with desirable and adjustable pore structure. Once developed and well defined, these pores can carry drugs and control their release. However, to create this type of nanoparticle is essencial to use surfactants since they act as pore template. Among the most important surfactants, cetyltrimethylammonium bromide (CTAB) highlights, a quaternary ammonium compound widely used as a surfactant in the synthesis of mesoporous silica nanoparticles (MSNs), hollow mesoporous silica (HMSNs) and core-shell MSNs. However, for achieving good results of drug-loaded pores it is necessary to remove CTAB by extraction techniques, which provides pores formation throughout the silica and the incorporation of molecules. During and after the removal process, it is possible that CTAB residues remains inside the pores, despide several removal processes are described as efficient in the complete removal of surfactants. In turn, the presence of CTAB residues can be advantageous, especially when considering its antimicrobial activity. Meanwhile, it should be noted that the presence of CTAB may present high toxicity risks. This review seeks to explore not only general aspects of the use of CTAB in the synthesis of MSNs, but also to assess its toxicity in prokaryotic and eukaryotic cells, in order to determine whether CTAB residues are acceptable in MSNs that will be used as drug delivery systems for further in vivo and clinical assays.


Assuntos
Nanopartículas , Dióxido de Silício , Cetrimônio , Porosidade , Tensoativos
19.
J Med Entomol ; 59(5): 1847-1852, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35900064

RESUMO

Present work aimed to identify blood feeding sources and attempt to detect Leishmania DNA in Nyssomyia antunesi, suspected vector of Leishmania sp., from a park in the urban center of Belém, the capital of Pará State, in the Brazilian Amazon. Entire bodies and gut contents of Ny. antunesi engorged females, previously captured in the urban park with Centers for Disease Control (CDC) light traps and aspiration on tree bases, were subjected to Leishmania and vertebrate DNA detection through amplification of the Leishmania mini-exon and vertebrate cytochrome b (cyt b) gene regions, respectively. The quality of DNA extraction from entire bodies was ensured through amplification of the dipteran cyt b region. The vertebrate cyt b amplicons were sequenced and compared with those available on GenBank. A maximum likelihood phylogenetic tree was constructed to assess the clustering patterns of these sequences. Leishmania DNA was not detected. The sequences of 13 vertebrate cyt b amplicons were considered informative, exhibiting similarity and clustering with the following six vertebrate species: Dasyprocta leporina (1), Cuniculus paca (1), Tamandua tetradactyla (4), Choloepus didactylus (4), Pteroglossus aracari aracari (2), Homo sapiens (1). The samples of D. leporina and C. paca were obtained from the CDC canopy, whereas the others were by aspiration from tree bases. The present results revealed the eclectic and opportunist blood-feeding behavior of Ny. antunesi, with birds and mammals, these last ones acting as potential reservoirs for Leishmania species, distributed throughout the vertical forest strata.


Assuntos
Kinetoplastida , Leishmania , Psychodidae , Animais , Brasil , Citocromos b/genética , Feminino , Insetos Vetores , Leishmania/genética , Mamíferos , Filogenia
20.
PeerJ ; 10: e13185, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356474

RESUMO

Background: Crop farming contributes to one of the most extensive land use activities in the world, and cropland areas continue to rise. Many vertebrate species feed on crops, which has caused an increase in human-wildlife conflicts in croplands. Crop-feeding damages the economy of local communities and causes retaliation against the responsible vertebrates in several forms, including lethal practices such as hunting and poisoning. Lethal control may cause the local extirpation of some species, affecting ecological processes and patterns. Therefore, it is necessary to find non-lethal alternatives that can protect both local economies and wildlife. Research has been conducted in Africa and Asia, focusing on elephants and primates, and the effectiveness of some non-lethal alternatives, such as chili-based repellents and beehives, is being investigated. However, there has been very little research on this topic in Central and South America. The goal of this review is to assess the current knowledge on crop damage by vertebrates in Central and South America and indicate future research directions. Survey methodology: We reviewed the available scientific literature reporting crop damage by vertebrates in Central and South America, and the Caribbean, published between 1980 and 2020, through systematic searches on Web of Science, Scopus, and Google Scholar. We analyzed the temporal and geographical distributions of the studies, the crops and vertebrate species these studies considered, the crop protection techniques used, and their effectiveness. Results: We retrieved only 113 studies on crop damage by vertebrates in Latin America, but there was an increasing trend in the number of studies published over time. Most of the studies were conducted in Brazil, Argentina, Mexico, and Costa Rica. Four orders of mammals (Rodentia, Carnivora, Artiodactyla, and Primates) and four orders of birds (Passeriformes, Columbiformes, Psittaciformes, and Anseriformes) were the most common groups of crop-feeding vertebrates. The most prominent crop was corn, which was featured in 49% of the studies. Other notable crops include rice, sorghum, and sugarcane. The most reported method for protecting crops was lethal control through hunting or poisoning. Non-lethal techniques were found to be less prevalent. Less than half of the studies that mentioned the use of protection techniques indicated their effectiveness, and only 10 studies evaluated it by performing scientific experiments and reporting their results. Conclusions: Central and South America is still underrepresented in research on vertebrate crop-feeding. There is a need for experimentation-based robust research to find crop protection techniques that minimize harm to vertebrates while effectively reducing damage to crops. While this is being studied, habitat loss and fragmentation need to be halted to prevent the native vertebrates from turning to crops for food.


Assuntos
Conservação dos Recursos Naturais , Vertebrados , Animais , Humanos , América Latina/epidemiologia , México , Animais Selvagens , Produtos Agrícolas , Brasil , Mamíferos
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