Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.694
Filtrar
1.
Vet Parasitol ; 277: 109009, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31862509

RESUMO

The present study investigated the effects of dietary supplementation with several Bacillus strains on growth performance, intestinal inflammatory and anti-inflammatory cytokines, anti-oxidants and tight junction (TJ) protein mRNA expression in broiler chickens challenged with mixed coccidia infection (oocysts of Eimeria tenella, Eimeria maxima and Eimeria acervulina). Ten different Bacillus strains were screened for their beneficial effects on coccidiosis challenge by measuring relative body weight gain (RBWG), lesion score, and total oocyst count. Three out of ten Bacillus strains were evaluated in depth by measuring RBWG, lesion score, total oocyst count, and the gene expression of proinflammatory (IL-6 and IL-8), anti-inflammatory (IL-10 and TGF-ß), anti-oxidant (SOD1 and HMOX1), and TJ (JAM2 and occludin) proteins. Our results showed that out of the ten different Bacillus strains, chickens fed with three strains, one Bacillus licheniformis and two Bacillus amyloliquefaciens, showed significantly higher RBWG, lower lesion scores (ceca, jejunum, and duodenum), and lower total fecal oocyst counts compared to non-Bacillus-fed control chickens. Post-coccidia challenge, the RBWG for the Bacillus-fed groups were 95-100 % as opposed to the control birds (70 %) at 6 days post infection (dpi) and 10 dpi. Similarly, the lesion scores for three organs were around 0.8-0.9 for the Bacillus-fed groups as opposed to control birds (lesion score range ∼1.4-2). The total oocyst counts were much lower in the Bacillus-fed group (10-20 folds lesser) than the control group. Furthermore, the Bacillus-fed groups showed differential gene expression at 3 dpi in different tissues, such as caecum, jejunum, and duodenum. Bacillus-fed chickens showed significant pro- and anti-inflammatory responses and higher expression of anti-oxidants and TJ proteins in the ceca, duodenum, and jejunum. Overall, our results demonstrated that dietary supplementation with Bacillus strains as direct-fed microbials (DFM) significantly improved the body weight gain after mixed coccidia challenge compared to non-Bacillus-fed and coccidia challenged control group. In conclusion, the results of this study are promising and indicate the many beneficial effects of DFM-supplementation in poultry diets to reduce the negative consequences of enteric diseases and to decrease economic losses imposed by coccidia infection in chickens.


Assuntos
Bacillus , Coccidiose/veterinária , Suplementos Nutricionais , Ração Animal , Animais , Bacillus/fisiologia , Galinhas/crescimento & desenvolvimento , Fezes/parasitologia , Intestinos/parasitologia , Intestinos/fisiologia , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/terapia
2.
Vet Parasitol ; 276: 108956, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31706235

RESUMO

Turkeys and chickens were orally infected with tissue cysts (one mouse brain) or oocysts (103, 105 or 106 oocysts) of three T. gondii strains of the clonal types II and III (ME49, CZ-Tiger, NED) to investigate the influence of the applied T. gondii strain and infective doses on the distribution of T. gondii in several organs and tissues and the serologic response of chickens and turkeys. Organ samples from 16 different tissues, including heart, brain, muscles and gizzard were analyzed by PCR. Brain and heart were found most frequently positive for T. gondii DNA in both species, followed by gizzard. Serological analysis with kinetic ELISA for turkey samples and IFAT for chicken samples were performed once a week. In both species a dose-depending serological response was found. Turkeys seroconverted one week after infection with CZ-Tiger strain and medium and high doses of ME49 oocysts. In chickens, infection with medium and high doses of CZ-Tiger led to seroconversion one week p.i. Frequency of T. gondii positive organs showed a trend of a dose-effect in both species after infection with the type II strains. The NED strain showed low virulence in chickens and turkeys, demonstrated by clearly less T. gondii positive organs. Infection with tissue cysts of all three strains revealed T. gondii stages in tissues of turkeys and chickens. In conclusion, our data show a risk for human infection with T. gondii due to consumption of chicken and turkey meat.


Assuntos
Galinhas/parasitologia , Modelos Animais de Doenças , Doenças das Aves Domésticas/parasitologia , Toxoplasmose Animal/parasitologia , Perus/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Encéfalo/parasitologia , Gatos , DNA de Protozoário/análise , Relação Dose-Resposta Imunológica , Moela das Aves/parasitologia , Coração/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Músculos/parasitologia , Organismos Livres de Patógenos Específicos , Toxoplasma/genética , Toxoplasma/imunologia
3.
Vet Parasitol ; 276: 108991, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31770701

RESUMO

Eimeria tenella, an obligate intracellular parasite, can actively invade the cecal epithelial cells of chickens and cause severe enteric disease. Eukaryotic elongation factor 2 (eEF2) plays a major role in protein synthesis and cell survival. This study aims to explore the exact mechanisms underlying diclazuril inhibition in second-generation merozoites of E. tenella. The eEF2 cDNA of the second-generation merozoites of E. tenella (EtEF2) was cloned by reverse transcriptase polymerase chain reaction and rapid amplification of cDNA ends. Diclazuril-induced expression profiles of EtEF2 were also analyzed. The cloned full-length cDNA (2893 bp) of the EtEF2 nucleotide sequence encompassed a 2499 bp open reading frame (ORF) that encoded a polypeptide of 832 residues with an estimated molecular mass of 93.12 kDa and a theoretical isoelectric point of 5.99. The EtEF2 nucleotide sequence was submitted to the GenBank database with the accession number KF188423. The EtEF2 protein sequence shared 99 % homology with the eEF2 sequence of Toxoplasma gondii (GenBank XP_002367778.1). The GTPase activity domain and ADP-ribosylation domain were conserved signature sequences of the eEF2 gene family. The changes in the transcriptional and translational levels of EtEF2 were detected through quantitative real-time PCR and Western blot analyses. The mRNA expression level of EtEF2 was 2.706 fold increases and the protein level of EtEF2 was increased 67.31 % under diclazuril treatment. In addition, the localization of EtEF2 was investigated through immunofluorescence assay. Experimental results demonstrated that EtEF2 was distributed primarily in the cytoplasm of second-generation merozoites, and its fluorescence intensity was enhanced after diclazuril treatment. These findings indicated that EtEF2 may have an important role in understanding the signaling mechanism underlying the anticoccidial action of diclazuril and could be a promising target for novel drug exploration.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria tenella/efeitos dos fármacos , Quinase do Fator 2 de Elongação/metabolismo , Doenças das Aves Domésticas/tratamento farmacológico , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , Eimeria tenella/genética , Quinase do Fator 2 de Elongação/genética , Feminino , Imunofluorescência , Masculino , Merozoítos/efeitos dos fármacos , Merozoítos/genética , Camundongos , Camundongos Endogâmicos BALB C , Nitrilos/farmacologia , Filogenia , Doenças das Aves Domésticas/parasitologia , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Triazinas/farmacologia
4.
Parasitol Res ; 118(11): 3173-3183, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31606835

RESUMO

Prevention of coccidiosis is one of the best ways of controlling disease. Therefore, the present study was carried out to evaluate the protective effect of ultraviolet (UV)-irradiated sporulated oocysts of Eimeria species against coccidiosis in layer chickens. One hundred forty-four one-day-old layer chicks were randomly divided into 4 groups (n = 36), including non-immunized/non-challenged negative control group (NC group), non-immunized/challenged control group (NIC group), non-irradiated sporulated oocyst/challenged group (CA group), and UV-irradiated sporulated oocyst/challenged (UV group). At the age of 4 days, chickens in groups UV and CA were both orally inoculated with 1.0 × 104 UV-irradiated and non-irradiated sporulated oocysts of Eimeria species, respectively. Chickens in groups NIC and NC were served as positive and negative controls, respectively. Chickens in all groups were orally challenged with 7.5 × 104 sporulated oocysts of Eimeria species except the NC group at the age of 21 days. The results revealed that chicks receiving UV-irradiated sporulated oocysts had no signs of illness with minimal or no changes in the cecal integrity and a significantly lower oocyst shedding (OPG) than in the NIC group. Additionally, the cytokine gene expression profiles were evaluated. Expression levels of IL-2, IL-12, and IFN-γ were significantly higher in the spleen of chicks in the UV and CA groups than in the NC group post-challenge. As expected, treatment with irradiated oocysts resulted in a significant reduction in oocyst shedding and maintenance of cecal mucosal integrity. Furthermore, the body weight was higher in chickens inoculated with UV-irradiated oocysts than their non-irradiated counterparts. In conclusion, our results demonstrate that inoculation with UV-irradiated sporulated oocysts of Eimeria species can produce a substantial reduction in infection symptoms.


Assuntos
Galinhas , Coccidiose/veterinária , Eimeria , Oocistos/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Animais , Peso Corporal , Coccidiose/prevenção & controle , Eimeria/imunologia , Eimeria/efeitos da radiação , Masculino , Oocistos/efeitos da radiação , Doenças das Aves Domésticas/parasitologia , Raios Ultravioleta , Vacinação/veterinária
5.
Exp Parasitol ; 207: 107775, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31628896

RESUMO

The ability to differentiate from the proliferative (tachyzoite) to the latent (bradyzoite) stage of isolates of Toxoplasma gondii recombinant genotypes (I/II/III and I/III) and reference strains from a clonal line (RH and ME49) was investigated in this study. Two isolates from chicken (#114 and #277; ToxoDB) and 3 from pigs (#114; ToxoDB) were the subjects for evaluation. The isolates were grown in cell culture under 2 different conditions: culture medium at pH 7.0 (neutral, without stress induction) or pH 8.0 (alkaline, stress inducing). After 4 days, the cultures were fixed and the events resulting from infection and induction were labeled. T. gondii cysts were labeled using Dolichos biflorus-FITC lectin (DBL-cysts) and free tachyzoites or vacuolar were labeled using an anti-T. gondii polyclonal antibody followed by an Alexa 594-conjugated secondary antibody (DBL-negative structures compatible with parasite structures - lysis plaques or vacuole). Differences in DBL-cysts formation in vitro in response to exogenous stress were observed between recombinant genotype isolates and the typical genotypes. The differences in conversion rates and the patterns of lysis plate production between genotype I/III isolates (#114) indicate that care should be taken when extrapolating the in vitro phenotypic characteristics of parasites from the same genotype.


Assuntos
Galinhas/parasitologia , Genótipo , Doenças das Aves Domésticas/parasitologia , Doenças dos Suínos/parasitologia , Toxoplasma/fisiologia , Toxoplasmose Animal/parasitologia , Análise de Variância , Animais , Brasil , Linhagem Celular , Meios de Cultura/química , Imunofluorescência , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Microscopia de Fluorescência , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Ovinos , Suínos , Toxoplasma/classificação , Toxoplasma/genética
6.
Vet Q ; 39(1): 153-160, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31625452

RESUMO

Granuloma disease in a flock of free range productive layers in the Netherlands in 2017 is described. The disease resembled granuloma outbreaks in layers caused by Tetratrichomonas gallinarum in 2013 and occurred in the same area in which the rearing farm considered as the source of the 2013 outbreaks was located. Between 55 and 84 weeks of age mortality was 20.3% (breeder's norm 3.9%). All dead hens examined (n = 20) showed granulomas especially in liver and ceca. Nine hens with or without liver and/or ceca granulomas were examined for trichomonads in mentioned organs by in situ hybridization (ISH), nested PCR, and cloning and sequencing. Ceca were also examined by culture. T. gallinarum ISH was positive in all livers and ceca with granulomas and negative in case granulomas were absent. T. gallinarum strain 13/16632, which caused the 2013 outbreaks was found in 4/8 hens with granulomas. Moreover, other trichomonads were detected: a T. gallinarum strain GPO-like and a Simplicimonas sp. strain GABC1-like. Mixed infections also occurred. Infectious causes of granuloma disease other than the afore-mentioned trichomonads could be excluded. Trichomonad DNA was not detected in environmental samples and wild ducks originating from the farm of concern, except for one duck in which the same Simplicimonas sp. as in hens was detected, leaving the source of the T. gallinarum infection in hens unknown. It is concluded that the herein described granuloma disease likely was caused by T. gallinarum strain 13/16632. However, the pathogenicity of the other trichomonads found remains to be clarified.


Assuntos
Granuloma/veterinária , Doenças das Aves Domésticas/parasitologia , Tricomoníase/veterinária , Animais , Autopsia/veterinária , Galinhas , Bases de Dados de Ácidos Nucleicos , Surtos de Doenças/veterinária , Patos , Feminino , Granuloma/parasitologia , Granuloma/patologia , Países Baixos , Doenças das Aves Domésticas/patologia , Trichomonas/genética , Tricomoníase/patologia
7.
Vet Res ; 50(1): 78, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601266

RESUMO

Veterinary vaccines need to have desired characteristics, such as being effective, inexpensive, easy to administer, suitable for mass vaccination and stable under field conditions. DNA vaccines have been proposed as potential solutions for poultry diseases since they are subunit vaccines with no risk of infection or reversion to virulence. DNA vaccines can be utilized for simultaneous immunizations against multiple pathogens and are relatively easy to design and inexpensive to manufacture and store. Administration of DNA vaccines has been shown to stimulate immune responses and provide protection from challenges in different animal models. Although DNA vaccines offer advantages, setbacks including the inability to induce strong immunity, and the fact that they are not currently applicable for mass vaccination impede the use of DNA vaccines in the poultry industry. The use of either biological or physical carriers has been proposed as a solution to overcome the current delivery limitations of DNA vaccines for veterinary applications. This review presents an overview of the recent development of carriers for delivery of veterinary DNA vaccines against avian pathogens.


Assuntos
Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Vacinas de DNA/administração & dosagem , Animais , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/virologia , Vacinação/métodos
8.
Ann Parasitol ; 65(3): 293-296, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31599558

RESUMO

Poultry production as one of the major sources of protein in Nigeria is constrained by parasitic diseases including haemo- and gastrointestinal (GI) parasites. The haemo- and endoparasites of indigenous chickens reared in Gwagwalada market, Gwagwalada Area Council, Abuja, Nigeria were studied. Blood and fecal samples were collected from 108 chickens (Gallus gallus domesticus) between April­August, 2017. Thin blood smear, and floatation and sedimentation techniques were used for the blood and fecal samples, respectively. Of the 108 local chickens examined, 49 were males, while 59 were females. Overall, female chickens had higher infection rate with haemoparasites (53.1%) that males (46.9%). The blood parasites found mostly were Plasmodium spp., with a prevalence 54.6%, occurring in both male and female chickens examined. It was further revealed that endoparasites infected 60.8% of the female local chicken and 39.2% of the male. The mostly occured Ascaridia spp. with prevalence 35.2%; the least was Strongyloides avium (0.9%). Also, Eimeria spp. occysts were found in 8 (7.4%) of the chickens. This study provides basic information on the haemo- and endoparasites constantly infecting local breed of chickens reared in Gwagwalada Area Council, FCT- Abuja.


Assuntos
Eimeria , Enteropatias Parasitárias , Doenças das Aves Domésticas , Animais , Galinhas/parasitologia , Feminino , Enteropatias Parasitárias/sangue , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Masculino , Nigéria , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/parasitologia
9.
BMC Vet Res ; 15(1): 366, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653218

RESUMO

BACKGROUND: Toxoplasma gondii, an intracellular apicomplexan protozoan parasite, can infect almost all warm-blooded animals. The aim of the present study was to investigate T. gondii oocyst-driven infection in pigs, chickens and humans in Jilin province, northeastern China. RESULTS: The serum samples of pigs, chickens and humans were sampled and tested by indirect enzyme-linked immunosorbent assays (ELISAs) using dense granule antigen GRA7, oocyst-specific protein OWP8, and sporozoite-specific protein CCp5A, respectively. Results showed a prevalence of 16.7% by GRA7-ELISA, and 12.2% by OWP8- and CCp5A-ELISA in pigs; 10.4% by GRA7-ELISA, 13.5% by OWP8-ELISA, and 9.4% by CCp5A-ELISA in chickens; and 14.2% by GRA7-ELISA, 3.6% by OWP8-ELISA, and 3.0% by CCp5A-ELISA in humans. No significant differences were observed between T. gondii seroprevalence in pigs and chickens among the three antigens-based ELISAs (P > 0.05). However, there were significant differences between T. gondii seroprevalence rates in humans (P < 0.05). These findings demonstrated a low prevalence of T. gondii oocyst-driven infection in humans, a medium prevalence in pigs, and a high prevalence in chickens. CONCLUSIONS: The present study demonstrated that different oocyst-driven infection rates in different animal species, which would help to design effective strategies to prevent T. gondii transmission. To our knowledge, this is the first study to differentiate T. gondii infective forms in pigs, chickens and humans in China.


Assuntos
Doenças das Aves Domésticas/parasitologia , Doenças dos Suínos/parasitologia , Toxoplasmose/epidemiologia , Animais , Antígenos de Protozoários/sangue , Galinhas , China/epidemiologia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Oocistos , Doenças das Aves Domésticas/epidemiologia , Proteínas de Protozoários/sangue , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia
11.
Turkiye Parazitol Derg ; 43(3): 155-157, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31502808

RESUMO

A 25-year-old male patient, who had terminal stage skin cancer (malignant melanocytic neoplasia) on his skin of arm was infected with white, round, worm parasites in the lesion area of the skin. Parasites were collected with a thin forceps in a petri dish, cleaned in warm physiological saline, fixed by 70% hot ethyl alcohol and clarified in lactophenol, respectively. All 14 female and 7 male nematodes, some of which had partial autolysis, were identified as Ascaridia galli, a chicken nematode. Due to the fact that it is a very rare case in the medical literature, we wish to report it.


Assuntos
Ascaridia/isolamento & purificação , Ascaridíase/diagnóstico , Melanoma/complicações , Neoplasias Cutâneas/complicações , Adulto , Animais , Braço , Ascaridia/classificação , Ascaridíase/parasitologia , Galinhas/parasitologia , Feminino , Humanos , Masculino , Doenças das Aves Domésticas/parasitologia
12.
Vet Parasitol ; 273: 105-111, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31473449

RESUMO

Diclazuril, which is widely used for the prevention of coccidiosis in chickens, has a lethal effect on asexual and sexual stages of Eimeria spp. However, little is known about its effect on the exogenous stages of Eimeria spp. In this study, we evaluated the effect of in vitro treatment with 0.2% diclazuril on unsporulated and sporulated oocysts of Eimeria spp. For this purpose, a total of 180 male layer chicks aged one day were randomly divided into 5 experimental groups. Each group was divided into 3 replicates of 12 chicks each. Group 1 (G1) and Group 2 (G2) were negative (non-immunized and non-challenged) and positive (non-immunized and challenged) controls, respectively. Group 3 (G3) was immunized per os with 1.0 × 104 non-diclazuril treated-sporulated oocysts. Groups 4 (G4) was immunized per os with 0.2% diclazuril treated-unsporulated oocysts (1.0 × 104) in which diclazzuril didn't affect sporulation. Group 5 (G5) was immunized per os with 0.2% diclazuril treated-sporulated oocysts (1.0 × 104). Chicks of G2, G3, G4, and G5 were challenged with 7.5 × 104 untreated sporulated oocysts at the age of 21 days, while the group 1 chicks remained unchallenged. G4 and G5 animals immunized with 0.2% diclazuril-treated oocysts showed a significant decrease in bloody diarrhea severity, lesion scores, and oocyst counts in comparison to those immunized with untreated oocysts. Furthermore, histopathologic findings showed a low number of parasitic stages in cecal tissues in G4 and G5. A significant increased body weight gain was observed in Gs 4 and 5 in comparison to G2. In addition, expression levels of IL-2, IL-12, and IFN-γ were significantly increased in G4 and G5. In conclusion, diclazuril is effective in attenuating Eimeria oocysts and thus provides an alternative approach for using diclazuril-treated oocysts to protect chicks against Eimeria challenge.


Assuntos
Coccidiose/veterinária , Eimeria/efeitos dos fármacos , Nitrilos/farmacologia , Oocistos/efeitos dos fármacos , Doenças das Aves Domésticas , Triazinas/farmacologia , Animais , Ceco/parasitologia , Galinhas , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Eimeria/patogenicidade , Masculino , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Distribuição Aleatória , Virulência/efeitos dos fármacos
13.
Parasitol Res ; 118(10): 2989-2999, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473858

RESUMO

Chicken coccidiosis is caused by the apicomplexan parasite Eimeria spp. At present, drug resistance of Eimeria is common because of the indiscriminate use of anticoccidial drugs. The gene encoding surface antigen 10 of Eimeria tenella (EtSAG10) is differentially expressed between drug-resistant and drug-sensitive strains. RNA-seq analysis indicated that this gene was downregulated in strains resistant to maduramicin and diclazuril compared to susceptible strains. EtSAG10 DNA sequence alignment revealed that they contained one and ten mutations in MRR and DZR, compared with DS, respectively. A full-length EtSAG10 cDNA was successfully cloned and expressed, and the polyclonal antibody was prepared. The transcription and translation levels of EtSAG10 were analyzed by quantitative real-time PCR (qPCR) and Western blotting. The localization of EtSAG10 in Spz, Mrz, and parasites in the first asexual stage was determined by indirect immunofluorescence. The potential association of EtSAG10 with sporozoite invasion of host cells was assessed by invasion inhibition assays. The results showed that EtSAG10 had a predicted transmembrane domain at the C-terminal end and a predicted signal peptide at the N-terminal end. EtSAG10 was downregulated in drug-resistant strains, which is consistent with the RNA-seq results. The EtSAG10 protein was localized to the parasite surface and parasitophorous vacuole membrane. This protein was shown to play a role in the infection of chicken intestine by sporozoites.


Assuntos
Antígenos de Protozoários/genética , Antígenos de Superfície/genética , Galinhas/parasitologia , Coccidiose/veterinária , Eimeria tenella/imunologia , Doenças das Aves Domésticas/parasitologia , Animais , Antígenos de Protozoários/metabolismo , Antígenos de Superfície/metabolismo , Coccidiose/parasitologia , Coccidiostáticos/farmacologia , Resistência a Medicamentos/genética , Eimeria tenella/efeitos dos fármacos , Eimeria tenella/genética , Eimeria tenella/crescimento & desenvolvimento , Regulação da Expressão Gênica , Mutação , Esporozoítos/genética , Esporozoítos/imunologia
14.
Vet Parasitol ; 272: 64-74, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31395207

RESUMO

This study aimed to evaluate the mite fauna and their ecological interactions in commercial laying hen farms in the state of Rio Grande do Sul, Brazil. It was conducted from August 2013 through August 2014 with two sampling strategies (feathers and traps) in three different production systems: automated (A1,2,3), semi-automated (S1,2) and free-range (FR). A total of 38,383 mites were collected belonging to 23 families and 33 species, most of which were collected in feathers (74%) followed by traps (26%). There was higher abundance at S1 (10,774-28.1%) and S2 (11,023-28.7%) followed by FR (6972-18.2%), A1 (1896-4.9%), A2 (4775-12.4%), and A3 (2943-7.7%). Higher richness was observed at S1 (23 species), S2 (18 species), and FR (19 species). Megninia ginglymura (Mégnin) (Analgidae) was the species with the highest health importance, eudominant on feathers, and its populations seems to be related with increased temperature. Tuccioglyphus setosus Horn et al. (Pyroglyphidae) seems to be influenced by relative air humidity and temperature. Predators with the highest populations were Cheyletus malaccensis (Oudemans) (Cheyletidae), Typhlodromus transvaalensis (Nesbitt) (Phytoseiidae), Blattisocius keegani (Fox), and Blattisocius dentriticus (Berlese) (Blattisocidae).


Assuntos
Infestações por Ácaros/veterinária , Ácaros/fisiologia , Doenças das Aves Domésticas/parasitologia , Criação de Animais Domésticos , Animais , Biodiversidade , Brasil , Galinhas , Feminino , Temperatura Alta , Umidade , Infestações por Ácaros/parasitologia , Ácaros/classificação , Controle Biológico de Vetores , Dinâmica Populacional , Fatores de Risco
15.
Avian Pathol ; 48(sup1): S35-S43, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31362523

RESUMO

Dermanyssus gallinae (De Geer, 1778) is a major problem for the poultry industry worldwide, as it negatively affects virtually all kinds of rearing systems. Therefore, the control of infestation has become a routine process, and its economic cost is constantly increasing. Until now, most of the control strategies have relied on the use of synthetic chemical drugs, but their efficacy is often questioned by the emergence and diffusion of resistant mite populations. With this in mind, the efficacy of λ-cyhalothrin, amitraz, and phoxim has been verified by testing them against 86 mite populations collected from the same number of poultry farms in Italy from 2008 to 2015. Assays were performed according to the filter paper method using the recommended, half, quarter, double and quadruple doses. The results showed that phoxim and amitraz were the most effective acaricides (median efficacies 80.35% and 80.83%, respectively), but amitraz exhibited a sharp fall in its efficacy during 2011 and 2012, while phoxim maintained its high effectiveness up to 2015, when it dropped. The overall median efficacy of λ-cyhalothrin was 58.33%. The data also highlighted the importance of the use of the right concentration, as an increase in dosage was not always useful against resistant populations, while its reduction also diminished efficacy, simultaneously increasing the risk for the development of resistance.


Assuntos
Acaricidas/farmacologia , Infestações por Ácaros/veterinária , Ácaros/efeitos dos fármacos , Doenças das Aves Domésticas/tratamento farmacológico , Animais , Itália , Infestações por Ácaros/tratamento farmacológico , Infestações por Ácaros/parasitologia , Nitrilos/farmacologia , Compostos Organotiofosforados/farmacologia , Aves Domésticas , Doenças das Aves Domésticas/parasitologia , Piretrinas/farmacologia , Inquéritos e Questionários , Toluidinas/farmacologia
16.
Avian Pathol ; 48(sup1): S17-S21, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31298932

RESUMO

A research centre with 30,568 laying hens, kept in enriched cages and in aviaries, had become naturally infested with poultry red mites (PRM) in 32 of its 48 bird units. Therefore, at the age of 52 weeks all hens were treated with fluralaner through the drinking water. After this treatment, PRM were no longer observed. As all birds were of the same age, and since production figures were measured daily in all 48 units, this offered a unique opportunity to examine how PRM had affected performance. Statistical analyses were done to compare the evolution of production data from the pre-treatment to the post-treatment period in units that were visually free of PRM or infested with PRM to different levels. Production standards provided by the breeding organizations were used as a reference. The results demonstrated significant posttreatment increases of laying percentage, egg weight, egg mass, percentage first choice eggs, feed intake and body weight in heavily infested hens of one or both housing systems, as compared to the non-infested controls. These data confirm that PRM infestations can impact the main performance traits related to profitability of laying hen farms as well as the hens' general condition.


Assuntos
Galinhas/parasitologia , Isoxazóis/administração & dosagem , Infestações por Ácaros/veterinária , Ácaros/fisiologia , Doenças das Aves Domésticas/parasitologia , Animais , Galinhas/crescimento & desenvolvimento , Água Potável , Fazendas , Feminino , Infestações por Ácaros/parasitologia
17.
Avian Pathol ; 48(sup1): S52-S59, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267762

RESUMO

The poultry red mite (PRM), Dermanyssus gallinae (De Geer, 1778), is a worldwide distributed ectoparasite and considered a major pest affecting the laying hen industry in Europe. Based on available information in other ectoparasites, the mite microbiome might participate in several biological processes and the acquisition, maintenance and transmission of pathogens. However, little is known about the role of PRM as a mechanical carrier or a biological vector in the transmission of pathogenic bacteria. Herein, we used a metaproteomics approach to characterize the alphaproteobacteria in the microbiota of PRM, and variations in its profile with ectoparasite development (nymphs vs. adults) and feeding (unfed vs. fed). The results showed that the bacterial community associated with D. gallinae was mainly composed of environmental and commensal bacteria. Putative symbiotic bacteria of the genera Wolbachia, C. Tokpelaia and Sphingomonas were identified, together with potential pathogenic bacteria of the genera Inquilinus, Neorickettsia and Roseomonas. Significant differences in the composition of alphaproteobacterial microbiota were associated with mite development and feeding, suggesting that bacteria have functional implications in metabolic pathways associated with blood feeding. These results support the use of metaproteomics for the characterization of alphaproteobacteria associated with the D. gallinae microbiota that could provide relevant information for the understanding of mite-host interactions and the development of potential control interventions. Research highlights Metaproteomics is a valid approach for microbiome characterization in ectoparasites. Alphaproteobacteria putative bacterial symbionts were identified in D. gallinae. Mite development and feeding were related to variations in bacterial community. Potentially pathogenic bacteria were identified in mite microbiota.


Assuntos
Alphaproteobacteria/isolamento & purificação , Galinhas/parasitologia , Microbiota , Ácaros/microbiologia , Doenças das Aves Domésticas/parasitologia , Animais , Feminino , Proteômica
18.
PLoS Negl Trop Dis ; 13(7): e0007435, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31295245

RESUMO

Toxoplasma gondii is a zoonotic protozoan with a worldwide occurrence, but the determinants of the current pattern in the geographical distribution of T. gondii lineages and strains remain poorly understood. To test the influence of human trade on T. gondii populations, we conducted a population genetic study of 72 T. gondii animal isolates from Senegal, a West African country in which the ongoing inland progress of invasive murine hosts (introduced in port cities of Senegal since the 16th century by European sailors) is well described. Isolates were mainly collected on free-range poultry, which are considered as relevant bioindicators of T. gondii strain diversity in the domestic environment. Sampling was conducted in two port cities of Senegal (Dakar and Saint-Louis) and in one inland region (Kedougou). Population genetic analyses using 15 microsatellite markers revealed different patterns between port cities where lineages non-virulent for mice (type II, type III, and Africa 4) were predominant, and Kedougou where the mouse-virulent Africa 1 lineage was the most common. By considering the current spatial pattern in the inland progress of invasive rodents in Senegal, our results suggest that the invasive house mouse Mus musculus domesticus counter-selects the Africa 1 lineage in the invaded areas. The comparison of the microsatellite alleles of type II strains from Senegal to type II strains from other areas in Africa and Western Europe, using discriminant analysis of principal components and Network analysis, point to a mainly Western European origin of the type II lineage in Senegal. Collectively, these findings suggest that human-mediated intercontinental migrations of murine hosts are important vectors of T. gondii strains. Differential susceptibility of endemic and introduced murine hosts to various T. gondii strains probably determines the persistence of these strains in the environment, and therefore their availability for human and animal infection.


Assuntos
Comércio , Variação Genética , Doenças das Aves Domésticas/transmissão , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/transmissão , África Ocidental/epidemiologia , Alelos , Animais , Galinhas/parasitologia , Reservatórios de Doenças/parasitologia , Europa (Continente)/epidemiologia , Genética Populacional , Genótipo , Geografia , Humanos , Camundongos/parasitologia , Repetições de Microssatélites , Filogenia , Filogeografia , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/parasitologia , Virulência
19.
Poult Sci ; 98(11): 5412-5415, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31328783

RESUMO

An important factor in efficient production of poultry is management of parasites. Ascaridia dissimilis is the most prevalent small intestinal nematode parasite of turkeys with up to 100% of flocks infected. High worm burdens can cause necrotic enteritis leading to high mortality in flocks. Recently, we were made aware of multiple cases where high burdens were seen at slaughter despite the administration of anthelmintics at frequent intervals, suggesting that resistance may have evolved in A. dissimilis. To address this issue, we obtained eggs of A. dissimilis from 4 commercial turkey farms and performed controlled efficacy tests to determine if fenbendazole resistance was present. Three farms had histories of frequent use of fenbendazole and worms found at slaughter, suggesting they may have resistance, and one was an organic farm where we had no additional history other than the farm had transitioned to organic production a few years earlier. For each worm isolate there were 2 treated and 2 untreated groups containing 9 birds each, with all groups being replicated in 2 separate rooms. Birds were infected with approximately 200 infective eggs, and treated groups received fenbendazole in the water (SafeGuard Aquasol, 1 mg/kg) for 5 consecutive days starting on day 24 post-infection. One week after the last treatment birds were necropsied, intestinal contents were collected and worms enumerated. Three of the four isolates demonstrated greater than 99% efficacy, indicating they were fully susceptible to fenbendazole. However, the fourth isolate demonstrated a significantly reduced efficacy of 63.89%, indicating the presence of resistance. Interestingly, this was the organic farm, whereas the 3 farms with "suspected" resistance all turned out to be fully susceptible. Given that 1 randomly acquired isolate of A. dissimilis, out of 4 tested, demonstrated resistance in this study, fenbendazole resistance may be a much larger problem on turkey farms than is currently recognized. Additional studies are needed to determine the prevalence of resistance, as well as the economic impact that resistant A. dissimilis have on turkey production.


Assuntos
Antinematódeos/farmacologia , Ascaridia/efeitos dos fármacos , Resistência a Medicamentos , Fenbendazol/farmacologia , Perus , Animais , Ascaridíase/parasitologia , Ascaridíase/veterinária , Feminino , Masculino , Doenças das Aves Domésticas/parasitologia
20.
Poult Sci ; 98(10): 4384-4390, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31329963

RESUMO

The present study aims to investigate the similarities and differences between the host cells apoptosis induced by virulent line of Eimeria tenella (Tsx) and precocious line (PTsx), which can provide a theoretical basis for the study of drugs and vaccines against coccidiosis. HE staining, Hoechst 33342/AnnexinV-FITC/PI composite staining, and ELISA were used to detect the infection rate, apoptosis rate, and Caspase-3 enzyme activity of host cells infected by PTsx or Tsx, respectively. The apoptotic rates and Caspase-3 absorbance of the inoculation groups were lower (P < 0.05 or P < 0.01) than those of the control group at 4 h, whereas the apoptotic rates and Caspase-3 absorbance of the inoculation groups were higher (P < 0.05 or P < 0.01) than those of the control groups at 24 to 120 h. At the same inoculation dose, there was no significant difference in the infection rate, apoptosis rate or Caspase-3 absorbance between Tsx groups and PTsx groups after E. tenella inoculation for 4 to 72 h (P > 0.05). However, these indicators of PTsx groups were lower (P < 0.01) than those of the same dose inoculated Tsx groups at 120 h. The apoptosis rates of cecal and glandular epithelial cells in the inoculated groups were higher (P < 0.01) than those in the control group after inoculated E. tenella 5 D in vivo, and the apoptosis rates of cecal and glandular epithelial cells in PTsx group was lower (P < 0.01) than that in the same dose inoculated Tsx group. These observations indicate that both Tsx and PTsx inhibit host cell apoptosis in the early development of E. tenella, induce host cell apoptosis in the middle and late stages, and the apoptosis-inducing effect on host cells increases with increasing dose. However, when the same dose of oocysts was inoculated, the amount of apoptosis induced by PTsx in late development was less than Tsx.


Assuntos
Apoptose , Galinhas , Coccidiose/veterinária , Eimeria tenella/fisiologia , Doenças das Aves Domésticas/imunologia , Animais , Coccidiose/imunologia , Coccidiose/parasitologia , Doenças das Aves Domésticas/parasitologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA