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1.
PLoS Pathog ; 16(6): e1008528, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32574210

RESUMO

Toxoplasma gondii and Hammondia hammondi are closely-related coccidian intracellular parasites that differ in their ability to cause disease in animal and (likely) humans. The role of the host response in these phenotypic differences is not known and to address this we performed a transcriptomic analysis of a monocyte cell line (THP-1) infected with these two parasite species. The pathways altered by infection were shared between species ~95% the time, but the magnitude of the host response to H. hammondi was significantly higher compared to T. gondii. Accompanying this divergent host response was an equally divergent impact on the cell cycle of the host cell. In contrast to T. gondii, H. hammondi infection induces cell cycle arrest via pathways linked to DNA-damage responses and cellular senescence and robust secretion of multiple chemokines that are known to be a part of the senescence associated secretory phenotype (SASP). Remarkably, prior T. gondii infection or treatment with T. gondii-conditioned media suppressed responses to H. hammondi infection, and promoted the replication of H. hammondi in recipient cells. Suppression of inflammatory responses to H. hammondi was found to be mediated by the T. gondii effector IST, and this finding was consistent with reduced functionality of the H. hammondi IST ortholog compared to its T. gondii counterpart. Taken together our data suggest that T. gondii manipulation of the host cell is capable of suppressing previously unknown stress and/or DNA-damage induced responses that occur during infection with H. hammondi, and that one important impact of this T. gondii mediated suppression is to promote parasite replication.


Assuntos
Coccídios/fisiologia , Coccidiose/metabolismo , Interações Hospedeiro-Parasita , Toxoplasma/fisiologia , Toxoplasmose/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Dano ao DNA , Humanos , Especificidade da Espécie
2.
Parasitology ; 148(11): 1328-1338, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34078494

RESUMO

Ectotherms are vulnerable to environmental changes and their parasites are biological health indicators. Thus, parasite load in ectotherms is expected to show a marked phenology. This study investigates temporal host­parasite dynamics in a lizard community in Eastern Spain during an entire annual activity period. The hosts investigated were Acanthodactylus erythrurus, Psammodromus algirus and Psammodromus edwardsianus, three lizard species coexisting in a mixed habitat of forests and dunes, providing a range of body sizes, ecological requirements and life history traits. Habitat and climate were considered as potential environmental predictors of parasite abundance, while size, body condition and sex as intrinsic predictors. Linear models based on robust estimates were fitted to analyse parasite abundance and prevalence. Ectoparasitic mites and blood parasites from two haemococcidian genera were found: Lankesterella spp. and Schellackia spp. Habitat type was the only predictor explaining the abundance of all parasites, being mostly higher in the forest than in the dunes. The results suggest that particularities in each host­parasite relationship should be accounted even when parasites infect close-related hosts under the same environmental pressures. They also support that lizard parasites can be biomarkers of environmental perturbation, but the relationships need to be carefully interpreted for each host­parasite assemblage.


Assuntos
Coccidiose/veterinária , Lagartos/parasitologia , Infestações por Ácaros/veterinária , Parasitemia/veterinária , Animais , Coccídios/classificação , Coccídios/fisiologia , Coccidiose/sangue , Coccidiose/parasitologia , Ecossistema , Feminino , Florestas , Modelos Lineares , Masculino , Infestações por Ácaros/parasitologia , Carga Parasitária/veterinária , Parasitemia/sangue , Parasitemia/parasitologia , Areia , Espanha
3.
J Invertebr Pathol ; 185: 107668, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34555364

RESUMO

Weathervane scallop, Patinopecten caurinus, the largest scallop species in the world, is distributed from northern California, U.S.A., to the Bering Sea, and is only commercially harvested in Alaska. The fishery is considered well managed by the State of Alaska (U.S.A) Department of Fish and Game (ADF&G) and federal government, with many precautionary measures in place to avoid overharvest. There have been episodic declines in some management areas due to unknown causes. Fishermen also encounter scallops with abnormal adductor muscles, a condition colloquially termed "weak meat", characterized by the retention of muscle when shucked, an obvious darkened discoloration, and/or an abnormal texture making the product unacceptable for marketing. A similar syndrome in Atlantic sea scallops, Placopecten magellanicus, described as "gray meat", occurs in the eastern U.S. and Canada, and proposed causes include senescence, loss of bioenergetics due to chronic infestations, or a synergism of these factors. Recently a severe apicomplexan infection was found to cause a gray meat condition in Iceland scallops, Chlamys islandica, and the collapse of that stock. This parasite was subsequently detected in Atlantic sea scallops with the gray meat condition off the U.S. East Coast. Studies that followed identified the parasite as Merocystis kathae, previously described from the common whelk, Buccinum undatum, more than 100 years ago. In 2015 Bering Sea fishermen reported weak meat in their catch, so samples were submitted to ADF&G for diagnosis. Adductor muscles from all affected scallops had many large foci of an apicomplexan associated with necrosis, fibrosis, and muscular atrophy. Given the reduced quality, marketability, and possibly fitness of affected scallops, we performed a survey to estimate prevalence, intensity, and geographic distribution of this apicomplexan in Alaskan weathervane scallops. We sampled 180 scallops, from individual beds within each of the three major geographically broad scallop areas in Alaska. Overall prevalence was about 82%, ranging from 69 to 100% by district. Overall mean infection intensity, based on the number of parasite foci/section, was about 9 (range of 5-29, by location), with scallops from the Bering Sea and Southwest Kodiak being most severely infected. Molecular analyses confirmed that the Alaskan parasite is M. kathae, i.e., the same apicomplexan that caused the collapse of Icelandic scallops and a suspected cause for gray meat and mass mortality of Atlantic sea scallops in northeast North America.


Assuntos
Coccídios/fisiologia , Parasitologia de Alimentos , Pectinidae/parasitologia , Alimentos Marinhos/parasitologia , Alaska , Animais
4.
J Exp Biol ; 222(Pt 17)2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31439651

RESUMO

Sperm performance is an important component of male reproductive success. However, sperm production is costly and males need to optimize their investment in sperm quality versus the somatic traits involved in mating success, e.g. their social status. As oxidative stress affects both sperm performance and somatic functions, it has been hypothesized to mediate such a trade-off. According to the oxidation-based soma/germline trade-off hypothesis, dominant males should favour the antioxidant protection of their somatic tissues, and subordinate males should favour the antioxidant protection of their sperm. We tested this hypothesis by experimentally infecting wild-caught house sparrows Passer domesticus with Coccidia Isopora sp., an internal parasite known to deplete antioxidant resources. We predicted that (i) increased parasite load affects sperm oxidative status and sperm performance and that (ii) males with experimentally high parasite load adjust the antioxidant protection of their soma versus their sperm according to their social status. Despite a 5400% increase in parasite load, sperm performance and somatic and spermatic oxidative status remained unaffected, irrespective of male social status. Nevertheless, males increased their sperm performance over time, a pattern mirrored by an increase in the antioxidant protection of their sperm. Moreover, males at the lower end of the hierarchy always produced sperm of lower velocity, suggesting that they were constrained and privileged their soma over their germline. To conclude, high parasite loads do not necessarily affect sperm performance and oxidative status. In contrast, social hierarchy and the relative investment in soma versus sperm antioxidant protection are determinants of sperm performance.


Assuntos
Doenças das Aves/fisiopatologia , Coccidiose/veterinária , Estresse Oxidativo , Análise do Sêmen/veterinária , Predomínio Social , Espermatozoides/fisiologia , Animais , Coccídios/fisiologia , Coccidiose/fisiopatologia , Masculino , Oxirredução , Pardais/fisiologia
5.
BMC Ecol ; 19(1): 12, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30836982

RESUMO

BACKGROUND: Parasite infections can have substantial impacts on population dynamics and are accordingly a key challenge for wild population management. Here we studied genetic mechanisms driving parasite resistance in a large herbivore through a comprehensive approach combining measurements of neutral (16 microsatellites) and adaptive (MHC DRB1 exon 2) genetic diversity and two types of gastrointestinal parasites (nematodes and coccidia). RESULTS: While accounting for other extrinsic and intrinsic predictors known to impact parasite load, we show that both neutral genetic diversity and DRB1 are associated with resistance to gastrointestinal nematodes. Intermediate levels of multi-locus heterozygosity maximized nematodes resistance, suggesting that both in- and outbreeding depression might occur in the population. DRB1 heterozygosity and specific alleles effects were detected, suggesting the occurrence of heterozygote advantage, rare-allele effects and/or fluctuating selection. On the contrary, no association was detected between genetic diversity and resistance to coccidia, indicating that different parasite classes are impacted by different genetic drivers. CONCLUSIONS: This study provides important insights for large herbivores and wild sheep pathogen management, and in particular suggests that factors likely to impact genetic diversity and allelic frequencies, including global changes, are also expected to impact parasite resistance.


Assuntos
Coccidiose/veterinária , Resistência à Doença/genética , Variação Genética , Enteropatias Parasitárias/veterinária , Repetições de Microssatélites , Infecções por Nematoides/veterinária , Doenças dos Ovinos/genética , Animais , Coccídios/fisiologia , Coccidiose/genética , Coccidiose/parasitologia , Feminino , Enteropatias Parasitárias/genética , Enteropatias Parasitárias/parasitologia , Nematoides/fisiologia , Infecções por Nematoides/genética , Infecções por Nematoides/parasitologia , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
6.
Mol Phylogenet Evol ; 127: 179-189, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29753710

RESUMO

Recent studies show that host switching is much more frequent than originally believed and constitutes an important driver in evolution of host-parasite associations. However, its frequency and ecological mechanisms at the population level have been rarely investigated. We address this issue by analyzing phylogeny and population genetics of an extensive sample, from a broad geographic area, for commonly occurring parasites of the genus Eimeria within the abundant rodent genera Apodemus, Microtus and Myodes, using two molecular markers. At the most basal level, we demonstrate polyphyletic arrangement, i.e. multiple origin, of the rodent-specific clusters within the Eimeria phylogeny, and strong genetic/phylogenetic structure within these lineages determined at least partially by specificities to different host groups. However, a novel and the most important observation is a repeated occurrence of host switches among closely related genetic lineages which may become rapidly fixed. Within the studied model, this phenomenon applies particularly to the switches between the eimerians from Apodemus flavicollis/Apodemus sylvaticus and Apodemus agrarius groups. We show that genetic differentiation and isolation between A. flavicollis/A. sylvaticus and A. agrarius faunas is a secondary recent event and does not reflect host-parasite coevolutionary history. Rather, it provides an example of rapid ecology-based differentiation in the parasite population.


Assuntos
Biodiversidade , Coccídios/fisiologia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Murinae/parasitologia , Animais , Coccídios/classificação , Coccídios/genética , Genética Populacional , Geografia , Haplótipos/genética , Interações Hospedeiro-Parasita/genética , Filogenia , Fatores de Tempo
7.
Syst Parasitol ; 94(1): 151-157, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28062994

RESUMO

A new species of coccidian, Isospora guaxi n. sp., and Isospora bellicosa Upton, Stamper & Whitaker, 1995 (Protozoa: Apicomplexa: Eimeriidae) are recorded from red-rumped caciques Cacicus haemorrhous (L.) in the Parque Nacional do Itatiaia, Brazil. Isospora guaxi n. sp. has sub-spheroidal oöcysts, measuring on average 30.9 × 29.0 µm, with smooth, bi-layered wall c.1.9 µm thick. Micropyle and oöcyst residuum are absent, but a polar granule is present. Sporocysts are ellipsoidal, measuring on average 19.3 × 13.8 µm. Stieda body is knob-like and sub-Stieda body is prominent and compartmentalized. Sporocyst residuum is composed of scattered granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa has sub-spheroidal to ovoidal oöcysts, measuring on average 27.1 × 25.0 µm, with smooth, bi-layered wall c.1.5 µm thick. Micropyle and oöcyst residuum are absent, but one or two polar granules are present. Sporocysts are ellipsoidal, measuring on average 18.1 × 10.9 µm. Stieda body is knob-like and sub-Stieda body is rounded to rectangular. Sporocyst residuum is composed of a cluster of compact or diffuse granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa was originally described from the Peruvian meadowlark Sturnella bellicosa deFilippi, a trans-Andean icterid which is allopatric with the cis-Andean C. haemorrhous. Therefore, in conclusion, this current study reveals the dispersion of coccidia from Icteridae across the Andes Mountains, besides describing the sixth isosporoid coccidium infecting an icterid bird.


Assuntos
Coccídios/fisiologia , Isospora/classificação , Isospora/fisiologia , Passeriformes/parasitologia , Animais , Brasil , Demografia , Isospora/citologia , Oocistos/citologia , Especificidade da Espécie , Esporozoítos/citologia
8.
Parasite Immunol ; 36(7): 277-91, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24702033

RESUMO

Infections of neonatal piglets with Cystoisospora suis are responsible for substantial economic losses in pig production. To investigate kinetics of T-cell populations, which are possibly involved in this infection, lymphocytes from blood, spleen, mesenteric lymph nodes and the jejunal mucosa of infected and noninfected piglets were investigated by flow cytometry and immunohistochemistry at five time points during the acute phase of primary infection. Additionally, mRNA expression levels of pattern recognition receptors and immunomodulatory cytokines in the jejunum were investigated. T-cell receptor-γδ(+) T cells were found to be increased in the gut mucosa 4 days after infection and were most likely involved in the primary local immune response. Five to eleven days later, cytotoxic T cells peaked in this location, which was preceded by an expansion of this lymphocyte population in the mesenteric lymph nodes. In intestines of infected piglets, mRNA expressions of TLR-2, NOD2 and TNF-α were significantly upregulated, suggesting an involvement in parasite recognition, immune response and possibly also in immunopathology. Taken together, this study identifies cellular and molecular players involved in the early immune responses against C. suis, but their precise role in the pathogenesis and control of this neonatal disease requires further investigation.


Assuntos
Coccídios/fisiologia , Coccidiose/veterinária , Doenças dos Suínos/imunologia , Subpopulações de Linfócitos T/imunologia , Actinas/genética , Animais , Complexo CD3/análise , Antígenos CD4/análise , Coccidiose/imunologia , Coccidiose/parasitologia , Citocinas/imunologia , Fezes/parasitologia , Subunidade alfa de Receptor de Interleucina-2/análise , Jejuno/imunologia , Jejuno/parasitologia , RNA Mensageiro/genética , Receptores de Antígenos de Linfócitos T gama-delta/análise , Suínos , Doenças dos Suínos/parasitologia , Transcrição Gênica
9.
Parasitology ; 141(2): 216-26, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24148558

RESUMO

Evidence of interference competition between the eimeriorin coccidian Aggregata sp. and the octopicolid copepod Octopicola superba at the level of the gills of naturally infected Octopus vulgaris is evaluated. Numerical and functional responses are considered for analysis, and the fundamental and realized spatial niches (FSNs and RSNs) are measured as part of the study. While it was not possible to measure the FSN of Aggregata sp., the analysis of the infection levels of O. superba recorded for non-concomitantly and concomitantly infected hosts suggests that the gills and body skin constitute, respectively, the main and accessory sites of infection of the parasite. According to the evidence found, the gills function mainly as an accessory site of infection of Aggregata sp., in specimens in which the caecum and intestine are massively infected. Evidence for a negative interaction between Aggregata sp. and O. superba has been found while controlling for a potential confounding effect of host size. Furthermore, the presence of O. superba on gill lamellae appears to have been negatively affected by the presence of Aggregata sp., while this latter remained mostly undisturbed. The mean number of oocysts of Aggregata sp. in the gills was higher in spring and summer, which were also the seasons presenting the broadest RSN for O. superba.


Assuntos
Coccídios/fisiologia , Copépodes/fisiologia , Octopodiformes/parasitologia , Animais , Coccídios/classificação , Coccídios/genética , Coccídios/isolamento & purificação , Copépodes/classificação , Copépodes/genética , Feminino , Trato Gastrointestinal/parasitologia , Brânquias/parasitologia , Interações Hospedeiro-Parasita , Masculino , Oocistos , Estações do Ano
10.
Vet Parasitol ; 331: 110253, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39032481

RESUMO

Gastrointestinal nematode (GIN) infection poses the most significant obstacle to the sustainable development of small ruminant (sheep and goat) farming globally. Resistance of GINs to synthetic anthelmintic drugs has led to rising interest in exploring alternative methods for parasite control, such as the utilization of bioactive plants with anti-parasitic properties. In this investigation, black seed (Nigella sativa), a shrub high in secondary antioxidant compounds, and sericea lespedeza (Lespedeza cuneata), a perennial legume high in tannins with anti-parasitic properties were combined to determine if two bioactive plants containing different types of secondary compounds can provide a stronger anti-parasitic effect than sericea lespedeza alone. In a 49-day trial, naturally parasitized 6-7-month-old intact male Spanish goats (n = 15/treatment) were fed pelletized feeds encompassing sericea lespedeza leaf meal (SL), a combination of black seed meal (BS) and sericea lespedeza leaf meal (BS-SL - 75 % SL, 25 % BS), or alfalfa (Medicago sativa, control parasitized; CONP), with an additional group of dewormed kids given the alfalfa pellets (Control treated; CONT). Weekly measurements of animal weights and samples of blood and feces were collected to determine the packed cell volume (PCV), GIN fecal egg counts (FEC), and coccidia fecal oocyte counts (FOC), respectively. All animals were processed at the end of the trial (60 total), with adult Haemonchus contortus worms recovered from the abomasum of each goat for counting and sex determination. Carcass weights were recorded after processing. Goats given the SL and BS-SL treatments had lower FEC (P<0.05) than the parasitized alfalfa (CONP) goats. At the end of the study, the SL and BS-SL groups' FOC values were lower (P < 0.05) than the CONT and CONP groups. A rise in PCV values was seen over time for all groups; SL, BS-SL, and CONT animals exhibited higher PCV values (P < 0.05) in comparison to the CONP goats. The parasitized goats fed SL-only pellets showed greater feed intake and animal body weights (P < 0.05) compared to goats fed BS-SL or alfalfa pellets. However, the treatments had no effect on the weight of the goats' carcasses. Although the H. contortus adult worm counts in the CONT goats (alfalfa-dewormed) were lower (P < 0.05) than in the CONP goats (alfalfa-parasitized), they did not differ from the SL or BS-SL animals. This study indicates that sericea lespedeza leaf meal pellet diet, either by itself or in combination with black seed meal, showed promising results as an anthelmintic and may prove to be an effective alternative to exclusive use of conventional deworming drugs. The addition of black seed did not appear to enhance the effectiveness of sericea lespedeza in this study.


Assuntos
Ração Animal , Doenças das Cabras , Cabras , Lespedeza , Infecções por Nematoides , Animais , Doenças das Cabras/parasitologia , Masculino , Ração Animal/análise , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Lespedeza/química , Coccidiose/veterinária , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Folhas de Planta/química , Gastroenteropatias/veterinária , Gastroenteropatias/parasitologia , Dieta/veterinária , Sementes/química , Nigella sativa/química , Nematoides/efeitos dos fármacos , Nematoides/fisiologia , Contagem de Ovos de Parasitas/veterinária , Fezes/parasitologia , Coccídios/efeitos dos fármacos , Coccídios/fisiologia , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Anti-Helmínticos/administração & dosagem
11.
Ecol Lett ; 16(8): 975-84, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23714379

RESUMO

Controlling parasites that infect multiple host species often requires targeting single species that dominate transmission. Yet, it is rarely recognised that such 'key hosts' can arise through disparate mechanisms, potentially requiring different approaches for control. We identify three distinct, but not mutually exclusive, processes that underlie host species heterogeneity: infection prevalence, population abundance and infectiousness. We construct a theoretical framework to isolate the role of each process from ecological data and to explore the outcome of different control approaches. Applying this framework to data on 11 gastrointestinal parasites in small mammal communities across the eastern United States reveals variation not only in the magnitude of transmission asymmetries among host species but also in the processes driving heterogeneity. These differences influence the efficiency by which different control strategies reduce transmission. Identifying and tailoring interventions to a specific type of key host may therefore enable more effective management of multihost parasites.


Assuntos
Coccidiose/veterinária , Gastroenteropatias/veterinária , Helmintíase Animal/parasitologia , Roedores , Musaranhos , Animais , Cestoides/fisiologia , Coccídios/fisiologia , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/transmissão , Gastroenteropatias/epidemiologia , Gastroenteropatias/parasitologia , Gastroenteropatias/prevenção & controle , Helmintíase Animal/transmissão , Modelos Biológicos , Nematoides/fisiologia , Densidade Demográfica , Prevalência , Estados Unidos/epidemiologia
12.
Biol Lett ; 9(4): 20130205, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-23658004

RESUMO

Individuals are often co-infected with several parasite species, yet the consequences of drug treatment on the dynamics of parasite communities in wild populations have rarely been measured. Here, we experimentally reduced nematode infection in a wild mouse population and measured the effects on other non-target parasites. A single oral dose of the anthelmintic, ivermectin, significantly reduced nematode infection, but resulted in a reciprocal increase in other gastrointestinal parasites, specifically coccidial protozoans and cestodes. These results highlight the possibility that drug therapy may have unintended consequences for non-target parasites and that host-parasite dynamics cannot always be fully understood in the framework of single host-parasite interactions.


Assuntos
Biota , Cestoides/fisiologia , Coccídios/fisiologia , Nematoides/fisiologia , Peromyscus/parasitologia , Animais , Anti-Helmínticos/administração & dosagem , Feminino , Ivermectina/administração & dosagem , Masculino , Nematoides/classificação , Densidade Demográfica , Estações do Ano , Especificidade da Espécie , Virginia
13.
Parasitol Res ; 112(9): 3295-304, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23820605

RESUMO

A growing body of literature reveals that the interactions among the parasite community may be strong and significant for parasite dynamics. There may be inter-specific antagonistic interactions as a result of competition and cross-effective immune response, or synergistic interactions where infection by one parasite is facilitated by another one, either by an impoverishment of the host's defenses, parasite-induced selective immunosuppression, or trade-offs within the immune system. The nature of these interactions may depend on how related are the parasite species involved. Here we explored the presence of associations among gastrointestinal parasites (coccidia and helminths) in natural populations of two wild mammal species, the capybara (Hydrochoerus hydrochaeris) and the guanaco (Lama guanicoe). The associations explored were between the oocyst outputs of a selected Eimeria species and the other coccidia of that parasite community, and between Eimeria spp. and the predominant nematodes. The statistical analysis included adjustment for potential confounders or effect modifiers. In guanacos, the prevailing interactions were synergistic among the coccidia and between coccidia and nematodes (Nematodirus spp.). However, in capybaras, the interaction between nematodes (Viannaiidae) and Eimeria spp. depended on environmental and host factors. The relationship was positive in some circumstances (depending on season, year, sex, or animal size), but it appeared to become antagonistic under different scenarios. These antagonist interactions did not follow a particular seasonal pattern (they occurred in autumn, spring, and summer), but they were predominantly found in females (when they depended on sex) or in 2010 and 2011 (when they depended on the sampling year). These results suggest that the relationship between coccidia and nematodes in capybaras may be context dependent. We propose that the context-dependent immune investment documented in capybaras may be the cause of these varying interactions.


Assuntos
Camelídeos Americanos/parasitologia , Coccidiose/veterinária , Enteropatias Parasitárias/veterinária , Infecções por Nematoides/veterinária , Doenças dos Roedores/parasitologia , Roedores/parasitologia , Animais , Coccídios/fisiologia , Coccidiose/parasitologia , Coinfecção , Eimeria/fisiologia , Meio Ambiente , Fezes/parasitologia , Feminino , Interações Hospedeiro-Parasita , Enteropatias Parasitárias/parasitologia , Masculino , Nematoides/fisiologia , Infecções por Nematoides/parasitologia , Oocistos , Fatores Sexuais
14.
Poult Sci ; 92(5): 1195-201, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23571328

RESUMO

This experiment was conducted to study the effects of whole yeast (Pichia guilliermondii; CitriStim, ADM, Quincy, IL) cell product supplementation on cecal microflora population and intestinal immune parameters in broilers. In the first experiment, birds were fed 0, 0.1, or 0.2% yeast cell wall product for 42 d. Feeding yeast cell wall products decreased (P = 0.03) the proportion of Escherichia coli in the ceca by 31% compared with the control group. The group fed 0.2% yeast cell wall product had a 20% decrease (P = 0.23) in Salmonella population compared with the control group. In the second experiment, birds were fed yeast cell wall product for 21 d and challenged or not challenged with coccidial oocysts, thus resulting in a 2 (0 and 0.2% whole yeast product) × 2 (coccidial challenge and no coccidial challenge) factorial model. Supplementing whole yeast cell wall product prevented a coccidial infection-induced decrease in the Lactobacillus population (P = 0.09) at 12 d postchallenge. Supplementing yeast cell wall product prevented a coccidial infection-induced increase in the Salmonella population (P = 0.08) and E. coli (P = 0.12) at 12 d postchallenge. At 5 d (P < 0.01) and 12 d (P < 0.01) postcoccidial infection, yeast cell wall product supplementation or coccidial infection increased the regulatory T cell (Treg) percentage in the cecal tonsils, whereas yeast cell wall product supplementation in the coccidial-infected group decreased the increase in Treg percentage. At 5 d postcoccidial infection, coccidial infection increased (P = 0.01) the relative amounts of cecal interferon (IFN)γ mRNA. In addition, the yeast cell wall product supplementation in the coccidial-infected groups further increased (P = 0.15) the IFNγ mRNA. It could be concluded that yeast cell wall product supplementation decreased coccidial-infection-induced increase in E. coli and Salmonella colonization and improved IFNγ mRNA amounts after coccidial infection.


Assuntos
Galinhas/fisiologia , Coccidiose/veterinária , Dieta/veterinária , Pichia/metabolismo , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , Prebióticos , Ração Animal/análise , Animais , Ceco/efeitos dos fármacos , Ceco/imunologia , Ceco/microbiologia , Coccídios/isolamento & purificação , Coccídios/fisiologia , Coccidiose/imunologia , Coccidiose/patologia , Suplementos Nutricionais/análise , Feminino , Interferon gama/imunologia , Interferon gama/metabolismo , Masculino , Contagem de Ovos de Parasitas/veterinária , RNA Mensageiro/genética , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Baço/efeitos dos fármacos , Baço/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
15.
Poult Sci ; 92(2): 358-63, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23300301

RESUMO

This experiment studied the effects of whole yeast cell product supplementation on broiler production parameters, fecal coccidial oocyst counts, and local and systemic immune parameters following an experimental coccidial infection. Birds were fed 0, 0.1, or 0.2% whole yeast cell product (CitriStim). At 21 d of age, birds were challenged with live coccidial oocysts. Supplementation with whole yeast cell product increased BW gain between 0 and 12 d (P = 0.01) postcoccidial challenge. Birds supplemented with 0.2% Citristim had better (P = 0.01) feed efficiency between 0 and 12 d postcoccidial infection. Supplementation with whole yeast cell product decreased (P = 0.01) the fecal coccidial oocyst count at 7 d postcoccidial challenge. Citristim supplementation at 0.2% increased (P < 0.01) macrophage nitric oxide production by 93 and 193% at 5 and 12 d postcoccidial challenge. Supplementation with whole yeast cell product at 0.2% increased cecal tonsil interleukin-1 mRNA amounts approximately 4.5- and 3.7-fold at 5 and 12 d postcoccidial challenge, respectively, over the group with no whole yeast cell product supplementation. Citristim supplementation downregulated cecal tonsil interleukin-10 mRNA amounts compared with the unsupplemented groups at both 5 (P = 0.01) and 12 d (P < 0.01) postcoccidial challenge. Supplementation with whole yeast cell product did not alter (P > 0.05) serum anticoccidial IgG contents or cecal tonsil CD4(+) and CD8(+) cell percentages at 5 and 12 d postcoccidial infection. It could be concluded that supplementing whole yeast cell product (CitriStim) to broiler diets can improve production parameters, decrease fecal oocyst count, and increase inflammatory cytokine production postcoccidial infection.


Assuntos
Galinhas/fisiologia , Coccidiose/veterinária , Dieta/veterinária , Pichia/metabolismo , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , Prebióticos , Ração Animal , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Ceco/efeitos dos fármacos , Ceco/imunologia , Ceco/metabolismo , Coccídios/isolamento & purificação , Coccídios/fisiologia , Coccidiose/imunologia , Coccidiose/patologia , Suplementos Nutricionais , Fezes/parasitologia , Jejuno/efeitos dos fármacos , Jejuno/patologia , Óxido Nítrico/metabolismo , Contagem de Ovos de Parasitas/veterinária , RNA/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo
16.
Int J Parasitol ; 52(13-14): 829-841, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36270547

RESUMO

Parasites of the order Coccidia (phylum: Alveolata, subphylum: Apicomplexa) have sophisticated life cycles that include a switch from asexual to sexual development, characterised by distinct cell types. During the development of gametes (gamogony), substantial changes occur at the cellular and subcellular levels, leading to cell fusion of micro- and microgametes, and the development of a zygote that forms a protective outer layer for environmental survival as an oocyst, the transmissible stage. Studies on the porcine coccidian Cystoisospora suis already identified changes in transcription profiles during different time points in the parasite's development and identified proteins with potential roles in the sexual development of this parasite. Here, we focus on three proteins that are possibly involved in the sexual development of C. suis. Enkurin and hapless protein 2 (HAP2) play important roles in signal transduction and gamete fusion during the fertilisation process, and oocyst wall forming protein 1 (OWP1) is a homologue of oocyst wall forming proteins of related parasites. We evaluated their locations in the different life cycle stages of C. suis and their inhibition by specific antibodies in vitro. Immunolocalization detected enkurin in merozoites and sporulated oocysts, HAP2 in merozoites and microgamonts, and OWP2 in merozoites, macrogamonts, oocysts and sporozoites. Up to 100% inhibition of the development of sexual stages and oocyst formation with purified chicken immunoglobulin IgY sera against recombinant enkurin, HAP2, and especially OWP1, were demonstrated. We conclude that the three investigated sexual stage-specific proteins constitute targets for in vivo intervention strategies to interrupt parasite development and transmission to susceptible hosts.


Assuntos
Coccídios , Sarcocystidae , Suínos , Animais , Coccídios/fisiologia , Oocistos , Sarcocystidae/genética , Merozoítos/metabolismo , Estágios do Ciclo de Vida
17.
Front Immunol ; 12: 621803, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149685

RESUMO

Feeding practices have been found to influence gut microbiota which play a major role in immunity of poultry. In the present study, changes in cecal microbiota and humoral responses resulting in the 55 ppm bacitracin (BACI), 1% each of cranberry (CP1) and wild blueberry (BP1) pomace alone or in combination (CP+BP) feeding in broiler Cobb 500 vaccinated or not against coccidiosis were investigated. In the non-vaccinated group, no significant treatment effects were observed on performance parameters. Vaccination significantly affected bird's performance parameters particularly during the growing phase from 10 to 20 days of age. In general, the prevalence of coccidiosis and necrotic enteritis (NE) was reduced by vaccination (P < 0.05). BACI-treated birds showed low intestinal lesion scores, and both CP1 and BP1 feed supplementations reduced Eimeria acervulina and Clostridium perfringens incidences similar to BACI. Vaccination induced change in serum enzymes, minerals, and lipid levels in 21-day old birds while, levels of triglyceride (TRIG) and non-esterified fatty acids (NEFA) were higher (P < 0.05) in CP1 treated non-vaccinated group than in the control. The levels of NEFA were lower in BACI- and CP1-fed birds than in the control in non-vaccinated day 28 old birds. The highest levels of all estimated three immunoglobulins (IgY, IgM, and IgA) were found in the vaccinated birds. Metagenomics analysis of the cecal bacterial community in 21-day old birds showed the presence of Firmicutes (90%), Proteobacteria (5%), Actinobacteria (2%), and Bacteroidetes (2%). In the vaccinated group, an effect of BACI was noted on Proteobacteria (P = 0.03). Vaccination and/or dietary treatments influenced the population of Lactobacillaceae, Enterobacteriaceae, Clostridiaceae, and Streptococcaceae which were among the most abundant families. Overall, this study revealed that besides their beneficial effects on performance, alike bacitracin, berry pomaces in poultry feed have profound impacts on the chicken cecal microbiota and blood metabolites that could be influenced by vaccination against coccidiosis.


Assuntos
Infecções Bacterianas/imunologia , Doenças das Aves/imunologia , Ceco/microbiologia , Galinhas/imunologia , Coccídios/fisiologia , Coccidiose/imunologia , Eimeria/fisiologia , Microbioma Gastrointestinal/imunologia , Vacinas Protozoárias/imunologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bacitracina , Mirtilos Azuis (Planta) , Imunidade Humoral , Metabolismo dos Lipídeos , Vacinação , Vaccinium macrocarpon
18.
Parasit Vectors ; 14(1): 248, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33971953

RESUMO

BACKGROUND: Swine coccidiosis, a protozoan disease caused by coccidia, can result in diarrhoea and weight loss in piglets and even economic losses in the pig industry. Here, we report the first systematic review and meta-analysis of the prevalence of coccidia (including Eimeria spp. and Cystoisospora suis) in pigs in China. METHODS: Five databases (PubMed, ScienceDirect, Chinese Web of Knowledge, Wanfang, and Chongqing VIP) were searched and 50 studies (46,926 domestic pigs, 22 provinces) ultimately identified pertaining to the prevalence of coccidia infection from 1980 to 2019. We incorporated the effect size using the random-effects model in the "meta" package in R software and conducted univariate and multivariate meta-regression analyses using a mixed-effects model. RESULTS: The pooled prevalence rate of coccidia in pigs was 21.9%, including the C. suis infection rate of 9.1%. The highest prevalence of coccidia (39.6%) was found in northwest China, and this region also presented the lowest prevalence of C. suis (4.7%). In the subgroup analysis based on sampling year, the highest prevalence of coccidia was detected in 2001 or earlier (32.6%), whereas the lowest rate was found in 2012 or later (14.3%). An opposite trend was observed for C. suis (5.5% in 2000 or earlier vs 14.4% in 2000 or later). The prevalence of coccidia in extensive farming systems (29.5%) was higher than that in intensive farming systems (17.3%). In contrast, the point estimate of C. suis prevalence was lower in the extensive farming systems (5.1%) than in the intensive farming systems (10.0%), but the difference was not significant (P > 0.05). Among the four age categories, the highest total coccidia prevalence (26.2%) was found in finishing pigs, followed by suckling piglets (19.9%), whereas the highest prevalence of C. suis (14.9%) was observed in suckling piglets. CONCLUSIONS: Our findings suggest that coccidia infection in Chinese pigs is common, although the prevalence of C. suis in pigs does not receive sufficient attention. We recommend the rational use of anticoccidial drugs to avoid drug resistance and the development of preventive and control measures for C. suis to reduce the incidence of swine coccidiosis.


Assuntos
Coccidiose/epidemiologia , Doenças dos Suínos/epidemiologia , Animais , China/epidemiologia , Coccídios/classificação , Coccídios/genética , Coccídios/isolamento & purificação , Coccídios/fisiologia , Coccidiose/parasitologia , Fezes/parasitologia , Prevalência , Suínos , Doenças dos Suínos/parasitologia
19.
Mol Biochem Parasitol ; 243: 111373, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33961917

RESUMO

The Coccidia is the largest group of parasites within the Apicomplexa, a phylum of unicellular, obligate parasites characterized by the possession of an apical complex of organelles and structures in the asexual stages of their life cycles, as well as by a sexual reproductive phase that occurs enterically in host animals. Coccidian sexual reproduction involves morphologically distinct microgametes and macrogametes that combine to form a diploid zygote and, ultimately, following meiosis and mitosis, haploid, infectious sporozoites, inside sporocysts within an oocyst. Recent transcriptomic analyses have identified genes involved in coccidian sexual stage development and reproduction, including genes encoding for microgamete- and macrogamete-specific proteins with roles in gamete motility, fusion and fertilization, and in the formation of the resilient oocyst wall that allows coccidians to persist for long periods in the environment. Transcriptomics has also provided important clues about the regulation of gene expression in the transformation of parasites from one developmental stage to the next, a complex sequence of events that may involve transcription factors such as the apicomplexan Apetala2 (ApiAP2) family, alternative splicing, regulatory RNAs and MORC (a microrchida homologue and regulator of sexual stage development in Toxoplasma gondii). The molecular dissection of coccidian sexual development and reproduction by transcriptomic analyses may lead to the development of novel transmission-blocking strategies.


Assuntos
Coccídios/fisiologia , Regulação da Expressão Gênica , Proteínas de Protozoários/genética , Processamento Alternativo , Coccídios/isolamento & purificação , Coccídios/patogenicidade , Perfilação da Expressão Gênica , Estágios do Ciclo de Vida , Merozoítos/genética , MicroRNAs , Oocistos/genética , RNA Longo não Codificante , RNA de Protozoário , Análise de Célula Única/métodos
20.
Parasit Vectors ; 14(1): 488, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551803

RESUMO

BACKGROUND: Acute and chronic besnoitiosis in extensive natural-service herds can have relevant effects in the health of bulls and negative consequences in their productive performance. Recent progress has been made in order to elucidate the pathogenesis of this disease. In this context, the study of biomarkers of inflammation in serum would contribute to gaining knowledge about the physiopathology of bovine besnoitiosis. Serological biomarkers could help in early diagnosis and prognosis, as seropositive bulls may have mild or severe testicular lesions. METHODS: Herein, we have investigated the diagnostic and/or prognostic value of a panel of serum (serological) biomarkers related to inflammation, including total protein, globulin and albumin, haptoglobin (Hp), adenosine deaminase (ADA) paraoxonase-1 (PON-1) and acetylcholinesterase (AChE) in naturally and experimentally B. besnoiti-infected males classified according to different clinical phases of the disease (acute, chronic and subclinical besnoitiosis). RESULTS: Results showed a similar response pattern in these biomarkers for naturally and experimentally infected cattle, with a few relevant variations. Most significant changes occurred during the acute phase of infection, although significant changes in a few biomarkers were also observed during the chronic infection. Haptoglobin, albumin, PON-1 and ADA were identified as the biomarkers that showed changes of higher magnitude in the acute phase of the infection, whereas high total protein and globulin values were found in chronically infected cattle. We have described the changes of a panel of inflammatory biomarkers of acute and chronic bovine besnoitiosis. CONCLUSIONS: In summary, several biomarkers with promising diagnostic value have been identified. The biomarkers associated with acute infection are related to previously reported molecular biomarkers in testicular parenchyma of infected bulls and could help in the diagnosis of early infections and complement results from specific immunoglobulin M (IgM) detection.


Assuntos
Biomarcadores/sangue , Doenças dos Bovinos/sangue , Coccidiose/veterinária , Acetilcolinesterase/sangue , Adenosina Desaminase/sangue , Animais , Arildialquilfosfatase/sangue , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/parasitologia , Coccídios/genética , Coccídios/fisiologia , Coccidiose/sangue , Coccidiose/imunologia , Coccidiose/parasitologia , Globulinas/análise , Haptoglobinas/análise
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