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1.
Rev Bras Parasitol Vet ; 30(1): e023020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605388

RESUMO

Neospora caninum is considered to be one of the main causes of abortion among cattle. The present survey was conducted in the municipality of Rolim de Moura, Rondônia State, Brazil. A questionnaire that investigates the epidemiological aspects of neosporosis was used in the analysis of risk factors associated with the animal-level and herd-level prevalence in dairy cattle. A total of 416 bovine blood samples were collected from 30 farms, and N. caninum antibody levels were measured by Indirect Fluorescent Antibody Test (IFAT). Analysis of dairy cattle serum samples revealed the presence of anti-N. caninum antibodies to be 47.36% (n = 197). Risk factors associated with N. caninum infection were the management system and access locations of dogs. The results of the present survey indicated that infection of dairy cattle with N. caninum is widespread in the studied region of Western Amazon, which has implications for prevention and control of neosporosis in this region. Therefore, integrated control strategies and measures are recommended to prevent and control N. caninum infection in dairy cattle. In addition, direct contact between dairy cattle, dogs and wild animals, which can influence the epidemiology of neosporosis, should be investigated further.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/transmissão , Coccidiose/epidemiologia , Coccidiose/prevenção & controle , Coccidiose/transmissão , Coccidiose/veterinária , Indústria de Laticínios , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Análise Fatorial , Feminino , Neospora/imunologia , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
2.
Vet Res ; 52(1): 24, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596990

RESUMO

Avian coccidiosis caused by Eimeria leads to huge economic losses on the global poultry industry. In this study, microneme adhesive repeat regions (MARR) bc1 of E. tenella microneme protein 3 (EtMIC3-bc1) was used as ligand, and peptides binding to EtMIC3 were screened from a phage display peptide library. The positive phage clones were checked by enzyme-linked immunosorbent assay (ELISA). Competitive ELISA was applied to further verify the binding capability between the positive phages and recombinant EtMIC3-bc1 protein or sporozoites protein. The inhibitory effects of target peptides on sporozoites invasion of MDBK cells were measured in vitro. Chickens were orally administrated with target positive phages and the protective effects against homologous challenge were evaluated. The model of three-dimensional (3D) structure for EtMIC3-bc1 was conducted, and molecular docking between target peptides and EtMIC3-bc1 model was analyzed. The results demonstrated that three selected positive phages specifically bind to EtMIC3-bc1 protein. The three peptides A, D and W effectively inhibited invasion of MDBK cells by sporozoites, showing inhibited ratio of 71.8%, 54.6% and 20.8%, respectively. Chickens in the group orally inoculated with phages A displayed more protective efficacies against homologous challenge than other groups. Molecular docking showed that amino acids in three peptides, especially in peptide A, insert into the hydrophobic groove of EtMIC3-bc1 protein, and bind to EtMIC3-bc1 through intermolecular hydrogen bonds. Taken together, the results suggest EtMIC3-binding peptides inhibit sporozoites entry into host cells. This study provides new idea for exploring novel strategies against coccidiosis.


Assuntos
Galinhas , Coccidiose/veterinária , Eimeria tenella/imunologia , Doenças das Aves Domésticas/prevenção & controle , Proteínas de Protozoários/imunologia , Esporozoítos/imunologia , Animais , Bacteriófagos , Ceco/patologia , Coccidiose/prevenção & controle , Simulação de Acoplamento Molecular , Doenças das Aves Domésticas/parasitologia , Ligação Proteica , Conformação Proteica
3.
Vet Res ; 52(1): 29, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602319

RESUMO

Rhomboid-like proteases (ROMs) are considered as new candidate antigens for developing new-generation vaccines due to their important role involved in the invasion of apicomplexan protozoa. In prior works, we obtained a ROM2 sequence of Eimeria maxima (EmROM2). This study was conducted to evaluate the immunogenicity and protective efficacy of EmROM2 recombinant protein (rEmROM2) and EmROM2 DNA (pVAX1-EmROM2) against infection by Eimeria maxima (E. maxima). Firstly, Western blot assay was conducted to analyze the immunogenicity of rEmROM2. The result showed that rEmROM2 was recognized by chicken anti-E. maxima serum. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assay revealed apparent transcription and expression of EmROM2 at the injection site. qRT-PCR (quantitative real-time PCR), flow cytometry and indirect ELISA indicated that vaccination with rEmROM2 or EmROM2 DNA significantly upregulated the transcription level of cytokines (IFN-γ, IL-2, IL-4, IL-10, IL-17, TGF-ß and TNF SF15), the proportion of CD8+ and CD4+ T lymphocytes and serum IgG antibody response. Ultimately, a vaccination-challenge trial was performed to evaluate the protective efficacy of rEmROM2 and pVAX1-EmROM2 against E. maxima. The result revealed that vaccination with rEmROM2 or pVAX1-EmROM2 significantly alleviated enteric lesions, weight loss, and reduced oocyst output caused by challenge infection of E. maxima, and provided anticoccidial index (ACI) of more than 160, indicating partial protection against E. maxima. In summary, vaccination with rEmROM2 or pVAX1-EmROM2 activated notable humoral and cell-mediated immunity and provided partial protection against E. maxima. These results demonstrated that EmROM2 protein and DNA are promising vaccine candidates against E. maxima infection.


Assuntos
Coccidiose/prevenção & controle , Eimeria/metabolismo , Peptídeo Hidrolases/metabolismo , Proteínas de Protozoários/metabolismo , Vacinas Protozoárias/imunologia , Animais , Galinhas , Clonagem Molecular , Eimeria/genética , Regulação da Expressão Gênica , Imunização Secundária , Imunoglobulina G/sangue , Peptídeo Hidrolases/genética , Proteínas de Protozoários/genética , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes
4.
Exp Parasitol ; 216: 107945, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32615133

RESUMO

Despite decades of investigation to clarify protective mechanisms of anticoccidial responses, one crucial field is neglected, that is, protective memory responses in primed birds. Protective memory immunity is critical for host resistance to reinfection and is the basis of modern vaccinology, especially in developing successful subunit vaccines. There are important differences between the immune responses induced by infections and antigens delivered either as killed, recombinant proteins or as live, replicating vector vaccines or as DNA vaccines. Animals immunized with these vaccines may fail to develop protective memory immunity, and is still naïve to Eimeria infection. This may explain why limited success is achieved in developing next-generation anticoccidial vaccines. In this review, we try to decipher the protective memory responses against Eimeria infection, assess immune responses elicited by various anticoccidial vaccine candidates, and propose possible approaches to develop rational vaccines that can induce a protective memory response to chicken coccidiosis.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/imunologia , Memória Imunológica/fisiologia , Doenças das Aves Domésticas/imunologia , Vacinas Protozoárias , Animais , Galinhas/imunologia , Coccidiose/imunologia , Coccidiose/prevenção & controle , Intestinos/imunologia , Intestinos/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , Recidiva , Vacinação/veterinária , Vacinas de Subunidades/imunologia
5.
Avian Dis ; 64(2): 123-129, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32550611

RESUMO

Eimeria spp. are important intestinal pathogens of chickens (Gallus gallus domesticus). Anticoccidial feed additives, chemicals, and ionophores have traditionally been used to control Eimeria infections in broiler production. Thus, the trend toward antibiotic-free and organic production requires new approaches to coccidiosis prevention. Two not mutually exclusive methods are the use of plant extracts with antiparasitic activity and manipulation of the intestinal microbiota by pre- and probiotics. In the present study, birds were inoculated with a combination of Eimeria acervulina, Eimeria maxima, and Eimeria tenella. We profiled the jejunal microbiome at multiple time points postinfection to investigate the changes in jejunum microbiota and to identify the time point of the maximum difference between infected and noninfected birds. Additionally, we assessed the anticoccidial effects of two anecdotal treatment methods, green tea and apple cider vinegar, as well as amprolium. Green tea and apple cider vinegar had no effect on oocyst shedding, but green tea reduced the mild unspecific lesions in coccidia-infected birds; there was no influence on unspecific lesions in uninfected controls. Jejunal contents were collected on the day of the infection and 1, 2, 4, 6, 10, and 14 days postinfection (dpi) for investigation of the intestinal microbiota by 16S ribosomal (r)RNA gene sequencing. Comparison of the untreated-uninfected and the untreated-infected groups showed a maximum community dissimilarity of 10 dpi. From 4 days after infection, Clostridiales were significantly enriched at the expense of Lactobacillales in infected compared with uninfected birds. Interestingly, treatment with green tea prevented proliferation of Clostridiales induced by the coccidia and increased the relative abundance of Melainabacteria.


Assuntos
Galinhas , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria/fisiologia , Microbioma Gastrointestinal/fisiologia , Doenças das Aves Domésticas/prevenção & controle , Ácido Acético/química , Amprólio/farmacologia , Animais , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Coccidiostáticos/química , Eimeria tenella/fisiologia , Sucos de Frutas e Vegetais , Jejuno/microbiologia , Malus/química , Doenças das Aves Domésticas/parasitologia , Chá/química
6.
Exp Parasitol ; 215: 107901, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32525007

RESUMO

Eimeria tenella (E. tenella) has caused severe economic loss in chicken production, especially after the forbidden use of antibiotics in feed. Considering the drug resistant problem caused by misuse of chemoprophylaxis and live oocyst vaccines can affect the productivity of chickens, also it has the risk to reversion of virulence, the development of efficacious, convenient and safe vaccines is still deeply needed. In this study, the EtMic2 protein of E. tenella was anchored on the surface of Lactobacillus plantarum (L. plantarum) NC8 strain. The newly constructed strain was then used to immunize chickens, followed by E. tenella challenge. The results demonstrated that the recombinant strain could provide efficient protection against E. tenella, shown by increased relative body weight gains, percentages of CD4+ and CD8+ T cells, humoral immune response and inflammatory cytokines. In addition, decreased cecum lesion scores and fecal oocyst shedding were also observed during the experiment. In conclusion, this study proves the possibility to use L. plantarum as a vessel to deliver protective antigen to protect chickens against coccidiosis.


Assuntos
Antígeno 12E7/imunologia , Galinhas/parasitologia , Coccidiose/veterinária , Eimeria tenella/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias , Animais , Antígenos de Protozoários/imunologia , Ceco/parasitologia , Coccidiose/economia , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Eimeria tenella/química , Citometria de Fluxo/veterinária , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Imunoglobulina A Secretora/biossíntese , Imunoglobulina G/sangue , Interferon gama/sangue , Interleucina-2/sangue , Intestinos/imunologia , Lactobacillus plantarum/genética , Lactobacillus plantarum/imunologia , Doenças das Aves Domésticas/economia , Doenças das Aves Domésticas/parasitologia , Distribuição Aleatória , Vacinas Sintéticas
7.
Poult Sci ; 99(3): 1320-1325, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32111308

RESUMO

Coccidiosis is a disease caused by Eimeria spp., resulting in approximately 3 billion US dollar loss in the poultry industry annually. The present study evaluated the effects of potential feed additives, 2-Nitro-1-propanol (NP) and nitroethanol (NE), on control of coccidiosis. An in vitro experiment indicated that both NP and NE inhibited the development of sporozoites in Madin-Darby bovine kidney cells (MDBK). The in vivo study was further conducted to evaluate the effects of NP and NE on growth performance, nitrogen-corrected apparent metabolizable energy (AMEn), and intestinal lesion scores of broilers challenged with Eimeria spps. Six treatments were tested in the study, including the nonchallenged control, challenged control, 100 ppm NP, 200 ppm NP, 100 ppm NE, and 200 ppm NE. Broilers were fed the treatment diets from day 12 until the end of the trial. All birds except the unchallenged control were challenged with Eimeria maxima, Eimeria tenella, and Eimeria acervulina on day 14. The growth performance was calculated, and the intestinal lesion was scored on day 20. The results showed that Eimeria challenge significantly reduced growth performance, increased intestinal lesion scores, and decreased AMEn compared with the nonchallenged control group. Birds fed with 200 ppm of NP had reduced growth performance compared with the nonchallenged control and challenged control. However, the supplementation of NP significantly improved AMEn and reduced cecal damage. Overall, NP and NE reduced sporozoites numbers in the MDBK cells. NP improved dietary digestibility of energy and reduces lesion scores in the ceca but could not maintain growth performance in broiler chickens infected with Eimeria spp.


Assuntos
Galinhas , Coccidiose/veterinária , Eimeria/efeitos dos fármacos , Nitrocompostos/metabolismo , Doenças das Aves Domésticas/prevenção & controle , Ração Animal/análise , Animais , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Masculino , Nitrocompostos/administração & dosagem , Doenças das Aves Domésticas/parasitologia , Propanóis/administração & dosagem , Propanóis/metabolismo , Distribuição Aleatória
8.
Vet Parasitol ; 279: 109061, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32143014

RESUMO

The microneme adhesive repeats (MAR) of Eimeria tenella microneme protein 3 (EtMIC3) are associated with binding to and invasion of host cells. Adhesion and invasion-related proteins or domains are often strongly immunogenic, immune responses mounted against these factors that play a key role in blocking invasion. In the present study, an oral live vaccine consisting of attenuated Salmonella typhimurium X4550 carrying two MAR domains fragment (St-X4550-MAR) was constructed and its protective efficacies were evaluated. The results showed that St-X4550-MAR was more immunogenic and conferred a higher degree of protection than recombinant MAR polypeptide as reflected by increased body weight, decreased oocyst shedding and lesion scores, increased serum IgG and cecal sIgA antibody production, and increasing levels of interferon-γ and interleukin-10. Thus, MAR domains are highly immunogenic and St-X4550-MAR had moderate activity against E. tenella infection by stimulating humoral, mucosal and cellular immunity. Chickens immunized with our constructed live vaccine provided considerable protections as early as at 10 d post-immunization (ACI: 155.17), and maintained higher protection levels at 20 d post-immunization (ACI: 173.66), and at 30 d post-immunization (ACI: 162.4). While the protective efficacy of chickens immunized with the recombinant MAR peptides showed a decreased trend as the post immunization time prolonging. Thus, using live-attenuated S. typhimurium X4550 as a vaccine expression and delivery system can significantly improve the protective efficacy and duration of protective immunity of MAR of EtMIC3.


Assuntos
Galinhas , Coccidiose/veterinária , Eimeria tenella/imunologia , Imunização/veterinária , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , Animais , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Masculino , Microrganismos Geneticamente Modificados , Doenças das Aves Domésticas/parasitologia , Salmonella typhimurium , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/imunologia
9.
Prev Vet Med ; 176: 104914, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32066028

RESUMO

Investigation of thymol efficacy to control pigeon coccidiosis was performed using in-vitro and in-vivo studies. The in-vitro experiment was conducted by treatment of unsporulated oocysts of Eimeria species of pigeon by five concentrations (0.625-10%) from either thymol, eucalyptus essential oil or amprolium anticoccidial drug and incubation for 72 h. The in-vitro study revealed that thymol concentrations ≥1.25 % caused significant deformity on sporulated and unsporulated oocysts compared to the other two products. Eucalyptus oil was active at both 5 and 10 % concentrations on unsporulated oocysts but showed non-significant changes on sporulated ones at all tested concentration. Meanwhile, in-vivo testing of thymol was conducted using 45 squabs which were equally divided into three groups; untreated uninfected (UU) negative control, untreated infected (UI) positive control and thymol treated (TT). TT group received 40 mg/kg BWt thymol in feed for 15 days. At day five post thymol supplementation, the UI and TT groups were orally infected by 25 × 103sporulated oocysts of pigeon Eimeria labbeana. The in-vivo study showed that thymol minimized the adverse effect of Eimeria infection in pigeon as observed by less severity of clinical signs, low oocysts count and improvement of body weight when compared with untreated infected birds. In addition, the biochemical parameters including liver and kidney functions tests proved thymol safety in pigeon. Moreover, thymol showed excellent antioxidant activity that was estimated by significantly lower value of malondialdehyde in TT than UI groups. The histopathological findings of TT group showed intact intestinal villi with mild sloughed epithelium, degenerated coccidian developmental stages and massive infiltrations of mononuclear cells in lamina propria. In conclusion, thymol can be safely used to control pigeon coccidiosis as a natural effective compound.


Assuntos
Antiparasitários/metabolismo , Coccidiose/veterinária , Eimeria/efeitos dos fármacos , Óleos Voláteis/uso terapêutico , Doenças das Aves Domésticas/prevenção & controle , Timol/metabolismo , Ração Animal/análise , Animais , Antiparasitários/administração & dosagem , Coccidiose/prevenção & controle , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Egito , Timol/administração & dosagem
10.
Vet Clin North Am Food Anim Pract ; 36(1): 187-203, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029184

RESUMO

Ruminant coccidiosis, caused by Eimeria species, is a significant and widespread enteric disease in young livestock worldwide. High morbidities and significant mortalities may be observed. For disease diagnosis, fecal samples from clinically ill animals should be analyzed for both, identity (ie, pathogenicity) of Eimeria species and excreted oocyst amount. To prevent coccidiosis-related economic losses, management measures to reduce infection pressure and improve general animal health are crucial. Anticoccidial drugs are widely used to control clinical and subclinical disease. Treatment is most efficient when applied prophylactically or metaphylactically. To avoid development of parasite drug resistance, drugs should be used sustainably.


Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Doenças das Cabras/parasitologia , Doenças dos Ovinos/parasitologia , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Coccidiose/prevenção & controle , Fezes/parasitologia , Doenças das Cabras/prevenção & controle , Cabras , Gado/parasitologia , Ruminantes/parasitologia , Ovinos , Doenças dos Ovinos/prevenção & controle
11.
Acta Trop ; 205: 105417, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32105666

RESUMO

Poultry industry has been very instrumental in curtailing malnutrition and poverty and as such contributing to economic growth. However, production loss in poultry industry due to parasitic disease such as coccidiosis has become a global challenge. Chicken coccidiosis is an enteric disease that is associated with morbidity and mortality. The control of this parasite through anticoccidial live vaccines and drugs has been very successful though with some limitations such as the cost of production of live vaccines, and drugs resistance which is a public health concern. The discovery of Eimeria vaccine antigens such as Apical membrane antigens (AMA)-1 and Immune mapped protein (IMP)-1 have introduced the use of recombinant vaccines as alternative control measures against chicken coccidiosis. Although some protections have been reported among recombinant vaccines, improving their protective efficacy has triggered the search for a novel and efficient delivery vehicle. Transgenic Eimeria, which is constructed either through stable or transient transfection is currently being explored as novel delivery vehicle of Eimeria vaccine antigens. Due to partial protections reported in chickens vaccinated with transgenic Eimeria lines expressing different Eimeria antigens, improving protective efficacy becomes imperative. Recent trends in the design of transgenic Eimeria for potential application in the control of chicken coccidiosis are summarized in this review. We conclude that, with improved protective efficacy using multiple vaccine antigens, transgenic Eimeria parasite could fill the gap in the control of chicken coccidiosis as an efficient anticoccidial vaccine.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/genética , Vacinas Protozoárias/imunologia , Animais , Coccidiose/prevenção & controle , Organismos Geneticamente Modificados , Doenças das Aves Domésticas/prevenção & controle
12.
Trop Anim Health Prod ; 52(4): 1985-1989, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31981055

RESUMO

The objective of the present study was to investigate the comparative efficacy of recommended dose of selected anticoccidial drugs Salinomycin, Dinitolmide, while Cocciban at three dose levels on the performance of broilers. For this purpose, 420-day-old commercial male broiler chicks were randomly divided into 7 treatment groups with 10 replications of 6 birds each and reared in battery brooders up to 42 days of age. Groups were designated as uninfected unmedicated (T1), infected unmedicated (T2), Cocciban 500 g/ton and infected (T3), Cocciban 750 g/ton and infected (T4), Cocciban 1000 g/ton and infected (T5), Salinomycin 500 g/ton and infected (T6), and Dinitolmide and infected (T7). Groups T2, T3, T4, T5, T6, and T7 were experimentally infected at 21 days old by 50,000 oocysts of Eimeria species. The broilers were fed with starter (0-21 days) and finisher diets (22-42 days). The herbal product Cocciban 1000 g/ton alone had significantly (P < 0.05) higher body weight gain and feed efficiency than all other infected groups during the overall experimental period (0-42 days), but significantly lower than healthy control. All the groups did not show significant (P > 0.05) effect on mean feed intake, percent carcass yields and percent weights of liver, heart and gizzard. Similarly there was no significant (P < 0.05) influence of treatment groups on the organoleptic characteristics of meat. Treatment groups did not have any significant (P < 0.05) influence on humeral immune response to ND vaccine and cell-mediated immune response to PHA-P. Among all the infected groups, Cocciban 1000 g/ton group (78.33%) recorded more mean percent livability than all other infected groups.


Assuntos
Galinhas , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria/efeitos dos fármacos , Doenças das Aves Domésticas/prevenção & controle , Animais , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Coccidiostáticos/classificação , Dinitolmida/farmacologia , Masculino , Oocistos/efeitos dos fármacos , Doenças das Aves Domésticas/parasitologia , Piranos/farmacologia
13.
Vet Parasitol ; 278: 109032, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31981858

RESUMO

Eimeria tenella, belonging to protozoon, is the causative agent of cecal coccidiosis in chicken and causes enormous impacts for poultry industry. The surface antigens of apicomplexan parasites function as attachment and invasion in host-parasite interaction. Meanwhile, host immune response is triggered as a result of parasitic invasion. Immunogenicity and potency as a vaccinal candidate antigen of E. tenella surface antigen 4 (EtSAG4) have been unknown. Therefore, a gene segment of E. tenella EtSAG4 was amplified and transplanted to pET28a prokaryotic vector for recombinant protein expression. Similarly, pEGFP-N1 eukaryotic vectors with EtSAG4 gene segment (pEGFP-N1-EtSAG4) amplified in 293 T cells as DNA vaccines. Reverse transcription-polymerase chain reaction (RT-PCR) assay and western blot analysis were used to demonstrate successful expressions of EtSAG4 in Escherichia coli or 293 T cells. Subsequently, animal experiments (72 cobb broilers) were performed to evaluate immunoprotective between recombinant protein and DNA vaccine of E. tenella EtSAG4 using different immunizing doses (50 or 100 µg), respectively. Serum from chickens infected with E. tenella identified recombinant EtSAG4 (rEtSAG4) protein. Chickens vaccinated with either rEtSAG4 protein or pEGFP-N1-EtSAG4 plasmids both shown a significant increase in concentration of IFN-γ (p < 0.05) compared with control groups indicating production of cell-mediated immunity. Besides, pEGFP-N1-EtSAG4 plasmids motivated more intense immune responses for immunoglobulin Y (IgY) and interleukin 17 (IL-17) (p < 0.05) contrast to control groups. However, there was no increase in concentration of interleukin 10 (IL-10) and interleukin 4 (IL-4) for both rEtSAG4 protein and pEGFP-N1-EtSAG4 plasmids. Chickens vaccinated with rEtSAG4 protein or pEGFP-N1-EtSAG4 plasmids both show higher weight, lower oocyst output and mean lesion scores compared with infection control groups. The highest anticoccidial index (ACI) value of immunized groups was 168.24 from EGFP-N1-EtSAG4 plasmids (100 µg) group. Generally, EGFP-N1-EtSAG4 plasmids as DNA vaccines provided a more effective immunoprotective for chickens against E. tenalla than that of rEtSAG4 protein as subunit vaccines. EtSAG4 is a promising candidate antigen gene for development of coccidiosis vaccine.


Assuntos
Antígenos de Protozoários/imunologia , Galinhas , Coccidiose/veterinária , Eimeria tenella/imunologia , Doenças das Aves Domésticas/prevenção & controle , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia , Animais , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Doenças das Aves Domésticas/parasitologia , Substâncias Protetoras/farmacologia , Distribuição Aleatória , Proteínas Recombinantes/imunologia , Vacinas de DNA/imunologia
14.
Vet Parasitol ; 277: 108967, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31812121

RESUMO

Neospora caninum infection is regarded as one of the most important infectious causes of abortion in dairy cattle. To intervene in its spread, four potential controls including test-and-cull, medication, vaccination, and selective breeding are considered and assessed in this study. The cost of each control, together with the inevitable annual loss due to population dynamics, is adopted as an assessment criterion from an economic point of view. By performing simulation and sensitivity analysis, our results demonstrate that compared with each single control, combined controls are worthwhile with better financial outcomes. For farm affected with significant prevalence (equal to or greater than 30%), vaccine treatment is the most effective and economical option among all control strategies. On the other hand, for farm where prevalence is relatively low (around 10%), combined control, by applying vaccination followed with test-and-cull, medication or selective breeding, could be alternative treatment to provide better financial outcome against single control in an observed period.


Assuntos
Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/terapia , Coccidiose/veterinária , Terapia Combinada/veterinária , Animais , Antiparasitários/uso terapêutico , Cruzamento , Bovinos , Doenças dos Bovinos/economia , Coccidiose/economia , Coccidiose/prevenção & controle , Coccidiose/terapia , Indústria de Laticínios/economia , Neospora/fisiologia , Dinâmica Populacional , Vacinas Protozoárias
15.
Microb Pathog ; 139: 103916, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812772

RESUMO

The objective of this study was to determine whether curcumin and a commercial microencapsulated phytogenic supplement containing thymol, cinnamaldehyde and carvacrol in broiler chicken feed would improve health and meat quality (fatty acid profile), as well as to determine the coccidiostatic and bactericidal potential of the additives. The broiler chickens were divided into five groups: NC - negative control feed; PC - positive control; CU - with 50 mg/kg of curcumin, PHY - 100 mg/kg phytogenic; and PHY + CU, a combination of both additives at 50 mg/kg (curcumin) and 100 mg/kg (phytogenic). We observed significantly higher levels of total proteins associated with increased circulating globulins, as well as lower levels of uric acid, cholesterol and triglycerides in the PHY + CU group than in the NC. There were significantly fewer oocysts in birds supplemented with additives in the NC group on day 21; on day 35, the NC, PHY and PHY + CU groups had significantly lower counts than the PC and CU groups; however, at 44 days, the lowest counts were in PC group. The bacterial counts were significantly lower on day 21 in all groups that received additives than those of the control group; however, at 44 days, the bacterial and Escherichia coli counts in these groups were significantly higher than those of the control. Curcumin with or without phytogenic agent improved meat quality, with increased antioxidant levels and reduction of lipid peroxidation. There were significantly lower total saturated fatty acid levels and significantly greater monounsaturated/polyunsaturated fatty acid levels in broilers that consumed additives individually and in combination. The combination of additives significantly increased the crypt/villus ratio, a marker of improved intestinal health and performance. Additives potentiated their individual effects, suggesting they can replace conventional growth promoters without compromising health, intestinal mucosa or meat quality.


Assuntos
Acroleína/análogos & derivados , Infecções Bacterianas/veterinária , Coccidiose/veterinária , Curcumina/administração & dosagem , Cimenos/administração & dosagem , Carne/análise , Doenças das Aves Domésticas/prevenção & controle , Timol/administração & dosagem , Acroleína/administração & dosagem , Ração Animal/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Infecções Bacterianas/metabolismo , Infecções Bacterianas/microbiologia , Infecções Bacterianas/fisiopatologia , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Galinhas/microbiologia , Galinhas/parasitologia , Coccídios/efeitos dos fármacos , Coccídios/genética , Coccídios/crescimento & desenvolvimento , Coccidiose/metabolismo , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Suplementos Nutricionais/análise , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/parasitologia
16.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 2065-2074, Nov.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1055118

RESUMO

Two experiments were conducted to evaluate the effect of thyme (Thymus vulgaris) essential oil (EO) doses on rumen fermentation, nutrient digestibility, and nitrogen metabolism, as well as performance and coccidia oocyst discharge. In experiment I, 20 rumen-cannulated wethers received the experimental diets containing 80% dry matter (DM) of haylage and 20% DM of concentrate. Treatments were 25mg of monensin/kg DM or doses of 1.25, 2.50, or 3.75g of thyme EO/kg DM. In experiment II, 50 ewe lambs received the same diets from experiment I, including a diet without feed additives. Wethers fed with diets containing 1.25g/kg DM of thyme EO had higher molar proportion of propionate (P= 0.03) and butyrate (P< 0.01), and lower (P= 0.04) acetate to propionate ratio than other treatments. Adding thyme EO to diets increased (P= 0.02) nitrogen retention compared to monensin. The performance of ewe lambs was not affected (P≥ 0.05) by treatments. However, lambs fed monensin had a lower (P= 0.04) number of coccidia oocyst discharge than others. Adding 1.25g/kg DM of thyme EO in high-forage diet improved ruminal fermentation. Thyme EO enhanced nitrogen metabolism, however, it did not improve performance.(AU)


Dois experimentos foram conduzidos para avaliar o efeito de doses de óleo essencial (OE) de tomilho (Thymus vulgaris) sobre a fermentação ruminal, a digestibilidade de nutrientes e o metabolismo de nitrogênio, bem como sobre o desempenho e a descarga de oocistos de coccídeos. No experimento I, 20 ovinos canulados receberam dietas experimentais contendo 80% de matéria seca (MS) de pré-secado e 20% de MS de concentrado. Os tratamentos foram 25mg de monensina/kg de MS ou doses de 1,25, 2,50 ou 3,75g de OE de tomilho/kg de MS. No experimento II, 50 borregas receberam as mesmas dietas do experimento I, incluindo uma dieta sem aditivos. Os animais alimentados com dietas contendo 1,25g de OE de tomilho apresentaram maior proporção molar de propionato (P=0,03) e de butirato (P<0,01) e menor (P=0,04) relação acetato/propionato do que outros tratamentos. A adição de OE de tomilho nas dietas aumentou (P=0,02) a retenção de nitrogênio em comparação com a monensina. O desempenho de cordeiros não foi afetado (P≥0,05) pelos tratamentos. No entanto, cordeiros alimentados com monensina apresentaram menor (P=0,04) número de oocistos de coccídeos. A adição de 1,25g/kg de MS de OE de tomilho na dieta forrageira melhorou o perfil da fermentação ruminal. O OE de tomilho aumentou a retenção de nitrogênio, no entanto não melhorou o desempenho.(AU)


Assuntos
Animais , Óleos Voláteis/uso terapêutico , Ovinos/metabolismo , Monensin , Coccidiose/prevenção & controle , Thymus (Planta)/química , Nitrogênio , Aditivos Alimentares
17.
J Anim Sci ; 97(12): 4746-4760, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31679027

RESUMO

This study examined the influence of a diet enriched with free methionine (dl-Met) or methionine dipeptide (dl-MMet) on the intestinal health of Eimeria-challenged (EC) and unchallenged (UC) broilers. A non-supplemented, methionine-deficient diet (NS) was used as control. Treatments were arranged in a 2 × 3 factorial completely randomized design with eight replications. Broilers in the EC group were infected with sporulated oocysts of Eimeria spp. (E. acervulina, E. maxima, E. praecox, and E. mitis) at 14 d of age. Performance analysis, light and electron microscopy of the jejunum, analysis of genes related to apoptosis and cell proliferation in the jejunum, and blood tests were performed at 6 days post-inoculation (dpi). EC broilers had poorer performance than UC broilers, regardless of diet (P < 0.001). Broilers fed the dl-Met diet had greater weight gain (P = 0.004) and lower feed conversion ratio (P = 0.019) than broilers fed other diets. Jejunal sections from EC broilers fed the NS diet showed short (P = 0.001) and wide villi (P < 0.001) with increased crypt depth (P < 0.001) and reduced villus / crypt ratio (P = 0.001), jejunal absorptive surface area (P < 0.001), number of neutral goblet cells (Eimeria challenge: P = 0.048; diet P = 0.016), and mucin 2 (MUC2) gene expression (P = 0.018). EC birds fed the dl-MMet diet had higher enterocyte height (P < 0.001). Birds fed the dl-MMet diet had low lamina propria width (P = 0.009). UC broilers fed the dl-Met diet had the highest number of acidic goblet cells (P = 0.005), whereas EC broilers assigned the dl-MMet diet showed the highest number of intraepithelial lymphocytes (P = 0.033). Reduced expression of caspase-3 (CASP3) (P = 0.005), B-cell lymphoma 2 (BCL2) (P < 0.001), mechanistic target of rapamycin (MTOR) (P < 0.001), and ribosomal protein S6 kinase B1 (RPS6KB1) (P < 0.001) genes was observed in EC animals. MTOR expression levels were highest in birds fed the dl-MMet diet (P = 0.004). Plasma activities of aspartate aminotransferase (AST) was influenced by both diet (P = 0.002) and Eimeria challenge (P = 0.005), with EC broilers assigned the NS diet showing the highest levels. EC broilers fed the NS diet had higher creatine kinase (CK) activity (P = 0.049). EC broilers had lower plasma uric acid (P = 0.004) and higher serum mucoproteins level (P < 0.001). These results indicate that methionine dipeptide supplementation is able to mitigate the harmful intestinal effects of Eimeria spp. in broilers.


Assuntos
Coccidiose/veterinária , Metionina/farmacologia , Doenças das Aves Domésticas/prevenção & controle , Ração Animal/análise , Animais , Galinhas , Coccidiose/prevenção & controle , Dieta/veterinária , Suplementos Nutricionais/análise , Eimeria , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Masculino , Metionina/administração & dosagem , Metionina/química , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/parasitologia
18.
Vet Parasitol ; 275: 108927, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31639571

RESUMO

A pilot study was conducted to evaluate the pathogenicity and immunogenicity of vaccinated rabbits with different doses of oocysts (5 × 102, 1 × 103, 1 × 104, and 5 × 104) of a precocious line, including Eimeria magna, E. intestinalis or E. media following the challenge with their corresponding parent strains. Our results showed that each precocious line had weak pathogenicity but good immunogenicity in terms of clinical symptoms, average daily weight gains (ADGs), and oocyst outputs. Therefore, a precocious line trivalent vaccine, including E. magna, E. intestinalis, and E. media was formulated. A total of sixty 40-day-old coccidia-free rabbits were allocated to ten treatments with a 2 × 3 factorial arrangement that included 2 vaccination doses (5 × 102 or 1 × 103 oocysts of the precocious line). Groups I to Ⅷ and Unimmunized Challenged Control group were challenged with mixed oocysts of their corresponding parent strains (1 × 104 oocysts of each parent strain) 14 days after vaccination. No clinical symptoms were observed in the immunized groups after vaccination. Average daily weight gains (ADGs) were similar to those of unimmunized unchallenged controls (P > 0.05) after vaccination or after challenge. Oocyst outputs in the vaccinated challenged groups were significantly different from those of unimmunized challenged controls (P < 0.01) after challenge. These results indicated that the trivalent vaccine could provide immune protection against coccidiosis and therefore, it could be used as a candidate vaccine.


Assuntos
Coccidiose/veterinária , Eimeria/imunologia , Vacinas Protozoárias , Coelhos/parasitologia , Análise de Variância , Animais , Coccidiose/imunologia , Coccidiose/prevenção & controle , Eimeria/classificação , Eimeria/patogenicidade , Fezes/parasitologia , Contagem de Ovos de Parasitas , Projetos Piloto , Vacinas Protozoárias/normas , Organismos Livres de Patógenos Específicos
19.
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
20.
Br Poult Sci ; 60(6): 766-776, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31483171

RESUMO

1. Two experiments were conducted, the first to determine the optimum inclusion of chitosan oligosaccharide (COS) in broiler diets to support growth performance, digestive functions, intestinal morphology, and immune organs. The second experiment evaluated the immune-protective properties of COS on broiler chickens during coccidia challenge (CC).2. Experiment 1 investigated the effect of graded dietary concentration of COS in the diets of broiler chickens using eight cage replicates for each of the six diets. A corn-soybean meal-based diet was used as the basal diet and supplemented with 0.0, 0.5, 1.0, 1.5, 2.0, or 2.5 g of COS/kg feed to form the six treatments.3. The diet supplemented with 1.0 g COS/kg of feed provided the optimal inclusion level for broiler chickens regarding body weight (BW) gain, jejunal villus height, villus height to crypt depth ratio, and ileal energy digestibility at d 22 of age.4. Experiment 2 investigated the immune-protective properties of COS in broiler chickens during CC. A total of 224 male broiler chicks were randomly assigned to eight replicate cages in a 2 × 2 factorial arrangement of treatments with two COS concentrations (0 or 1 g of COS/kg of diet), with or without CC.5. On d 18 of age, birds in the CC group received twice the recommended coccidia vaccine dose of 30 doses/kg BW.6. Coccidia challenge reduced (P < 0.05) and dietary COS increased (P < 0.05) BW gain, and feed intake. Dietary COS mitigated (P < 0.05) the CC-induced effects on gain:feed. Dietary COS supplementation attenuated the CC-induced effects (P < 0.05) on the expression of occludin genes.7. In conclusion, dietary COS improved performance, and the immune-related beneficial impact of COS supplementation was associated with reduced expression of pro-inflammatory cytokine genes.


Assuntos
Galinhas/parasitologia , Quitosana/administração & dosagem , Coccidiose/veterinária , Doenças das Aves Domésticas/dietoterapia , Ração Animal/análise , Ração Animal/normas , Criação de Animais Domésticos , Animais , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Coccidiose/dietoterapia , Coccidiose/imunologia , Coccidiose/prevenção & controle , Citocinas/sangue , DNA Complementar/química , Dieta/veterinária , Suplementos Nutricionais , Digestão , Fezes/parasitologia , Íleo/anatomia & histologia , Íleo/fisiologia , Jejuno/anatomia & histologia , Masculino , Contagem de Ovos de Parasitas/veterinária , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/parasitologia , Vacinas Protozoárias/administração & dosagem , RNA de Protozoário/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Soja , Ganho de Peso , Zea mays
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