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1.
Trop Anim Health Prod ; 53(5): 497, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609608

RESUMO

To explore the potential alternative of anti-coccidials, we investigated the therapeutic efficacy of dietary Piper sarmentosum extract (PSE) on induced coccidia infection in chickens. A total of 96-day-old chickens were randomly distributed to 1 of 3 treatment groups, including (1) control negative untreated uninfected (CN), (2) control positive untreated infected (CP), and (3) Piper sarmentosum (P. sarmentosum) extract-treated infected group (PSE). Our results demonstrated that E. tenella challenged untreated group showed a reduction (P < 0.05) in post-infection (PI) body weight compared to control negative group. However, supplementation of P. sarmentosum extract had no significant effects on body weight and cecal lesions compared with control positive group. Infected chickens fed PSE diet decreased (P < 0.05) the bloody diarrhea scores and oocyst shedding (during the day 5 to 8 post-infection) than that of CP chickens. E. tenella-challenged chickens upregulated (P < 0.05) the mRNA expression of IL-8 and Bcl-2 compared to PSE chickens, while IFN-γ compared to CN chickens. On the other hand, treatment of P. sarmentosum extract tended to increase (P < 0.05) the transcription patterns of IL-4, IL-10, CLDN 1, SOD 1, and Bax with the comparison of control positive group; however, there were no significant effects on IL-8, ZO 1, and CAT expression between the PSE and CP groups. Collectively, these findings elaborated that dietary P. sarmentosum extract exhibit potential anti-coccidial effects in controlling the coccidia infection in chickens.


Assuntos
Coccidiose , Eimeria tenella , Piper , Doenças das Aves Domésticas , Animais , Galinhas , Coccidiose/tratamento farmacológico , Coccidiose/veterinária , Suplementos Nutricionais , Doenças das Aves Domésticas/tratamento farmacológico
2.
Trop Anim Health Prod ; 53(5): 493, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599403

RESUMO

Proper health management is essential for productivity in duck farming. However, there is limited information on the effect of management conditions on rates of metabolic problems and parasitic infections in anatids. We evaluated the rates of metabolic syndromes and gastrointestinal parasite involvement in Muscovy ducks up to 12 weeks of age, under 3 management conditions: backyard, organized, and organized with probiotics. Individuals under organized management developed 2 metabolic problems: ascites, which was rare (3.5%), fatal, and affected both males and females, and angel wing syndrome, which was more frequent (10.6%), has low impact on general health, and only affected males. The treatments do not have a significant effect on the development of ascites, but only individuals in controlled conditions presented this syndrome, and due to its low prevalence, further studies with a larger sample size are required. The risk of angel wing syndrome increased significantly with probiotic supplementation. Regarding to parasitic infection, the improvement of sanitary management and the use of probiotics supplementation reduced the occurrence of coccidiosis. Similarly organized management with probiotic supplementation showed a protective effect on helminthiasis by reducing the frequency of Heterakis gallinarum and greatly reducing the helminth egg load. Coccidiosis and helminthiasis infections were not significantly correlated with the final weight of the ducks. Therefore, organized management and the use of probiotics seems to reduce the impact of parasitic infection, although it increases the risk of developing metabolic syndrome.


Assuntos
Coccidiose , Doenças Transmissíveis , Síndrome Metabólica , Doenças Parasitárias , Animais , Coccidiose/veterinária , Doenças Transmissíveis/veterinária , Patos , Feminino , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/veterinária
3.
Rev Bras Parasitol Vet ; 30(3): e010621, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495126

RESUMO

Aimed with this study to evaluate vertical transmission of Neospora caninum in naturally infected sheep and to monitor the kinetics of antibodies against this protozoon in their lambs. Therefore, 48 pregnant ewes, from five herds, were divided into two groups: G1 - positive for anti-N. caninum antibodies, with 19 animals; and G2 - seronegative, with 29 animals. Blood samples were taken from the ewes and their lambs, immediately after birth, before ingesting colostrum, and 2, 7, 14, 21, 28, 35, 42, 49 and 56 days after birth. Analysis on serum antibodies was performed using the indirect immunofluorescent antibody test. Among the 19 seropositive mothers, six (31.6%) gave birth to lambs seropositive before ingesting colostrum and it was found that these lambs remained positive until the end of the study (56 days). Only one of the lambs, from a ewe that presented an antibody titer of 200, seroconverted after ingestion of colostrum. All the lambs that had been born from negative mothers remained negative throughout the experimental period. It was concluded that transplacental transmission was an important form of diffusion of N. caninum in the herds studied and that seropositive lambs maintained circulating antibodies during the period analyzed.


Assuntos
Coccidiose , Neospora , Doenças dos Ovinos , Animais , Anticorpos Antiprotozoários , Brasil , Coccidiose/veterinária , Feminino , Transmissão Vertical de Doenças Infecciosas/veterinária , Cinética , Gravidez , Ovinos
4.
BMC Genomics ; 22(1): 660, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521339

RESUMO

BACKGROUND: Coccidiosis is an infectious disease with large negative impact on the poultry industry worldwide. It is an enteric infection caused by unicellular Apicomplexan parasites of the genus Eimeria. The present study aimed to gain more knowledge about interactions between parasites and the host immune system during the early asexual replication phase of E. tenella in chicken caeca. For this purpose, chickens were experimentally infected with E. tenella oocysts, sacrificed on days 1-4 and 10 after infection and mRNA from caecal tissues was extracted and sequenced. RESULTS: Dual RNA-seq analysis revealed time-dependent changes in both host and parasite gene expression during the course of the infection. Chicken immune activation was detected from day 3 and onwards with the highest number of differentially expressed immune genes recorded on day 10. Among early (days 3-4) responses up-regulation of genes for matrix metalloproteinases, several chemokines, interferon (IFN)-γ along with IFN-stimulated genes GBP, IRF1 and RSAD2 were noted. Increased expression of genes with immune suppressive/regulatory effects, e.g. IL10, SOCS1, SOCS3, was also observed among early responses. For E. tenella a general up-regulation of genes involved in protein expression and energy metabolism as well as a general down-regulation genes for DNA and RNA processing were observed during the infection. Specific E. tenella genes with altered expression during the experiment include those for proteins in rhoptry and microneme organelles. CONCLUSIONS: The present study provides novel information on both the transcriptional activity of E. tenella during schizogony in ceacal tissue and of the local host responses to parasite invasion during this phase of infection. Results indicate a role for IFN-γ and IFN-stimulated genes in the innate defence against Eimeria replication.


Assuntos
Coccidiose , Eimeria tenella , Doenças das Aves Domésticas , Animais , Galinhas/genética , Coccidiose/genética , Coccidiose/veterinária , Eimeria tenella/genética , Perfilação da Expressão Gênica , Doenças das Aves Domésticas/genética , RNA-Seq
5.
Avian Dis ; 65(1): 77-85, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339126

RESUMO

Infection of poultry with Eimeria spp., the causative agent of coccidiosis, can predispose birds to necrotic enteritis (NE) caused by netB gene-positive strains of Clostridium perfringens. The detection of Eimeria spp., C. perfringens, and netB were examined in settled dust from broiler flocks under experimental and field conditions. Dust samples were collected from settle plates twice weekly from two experimental flocks inoculated with three species of pathogenic Eimeria in 9-day-old chicks, followed by netB gene-positive C. perfringens 5 days later to produce subclinical and clinical NE. A noninoculated flock was sampled weekly from day 0 and served as a control flock. An additional 227 dust samples from commercial broiler flocks were collected at the end-of-batch (6-7 wk of age; one scraped dust sample per flock). In the NE-subclinical and NE-clinical flocks, high levels of Eimeria spp. and C. perfringens were detected after inoculation followed by a gradual decline over time. In the control flock, C. perfringens and netB were detected at low levels. No significant effect of sampling location was evident on Eimeria spp., C. perfringens, and netB load within poultry houses. These results provide evidence that Eimeria spp., C. perfringens, and netB gene copies can be readily measured in poultry dust samples collected in settle plates and may provide an alternative sampling method for monitoring flock coccidiosis and NE status. Further studies are required to assess the utility for such a test in commercial flocks.


Assuntos
Toxinas Bacterianas/análise , Galinhas , Infecções por Clostridium/veterinária , Clostridium perfringens/isolamento & purificação , Coccidiose/veterinária , Eimeria/isolamento & purificação , Enterotoxinas/análise , Doenças das Aves Domésticas/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Animais , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Coccidiose/epidemiologia , Coccidiose/parasitologia , Poeira , New South Wales/epidemiologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/parasitologia
6.
Poult Sci ; 100(9): 101329, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34333387

RESUMO

This study evaluated growth performance and cross-protection against Eimeria spp. using a subunit coccidia vaccine in 2 independent challenge experiments. In both trials, chickens were challenged with E. acervulina, E. maxima, and E. tenella oocysts. In Exp 1, 1000-day-old chickens were allocated in one of 2 treatments 1) Control group; 2) Biotech Vac Cox group. The vaccine was orally gavaged on d 2 and 16 of life and coccidia challenge was on d 21. Performance parameters were evaluated on d 21, 35, and 42. On d 34, coccidia lesions were scored. Oocysts per gram of feces (OPG) were evaluated on d 28, 35, and 42. In Exp 2, 900-day-old chickens were assigned in one of 2 treatments 1) Control group; 2) Biotech Vac Cox group. The vaccine was orally gavaged on d 2 and 16 of life and coccidia challenge was on d 21. Performance parameters were evaluated on d 21, 27, 35, and 42, and lesion scores and OPG at d 27. In Exp 1, chickens vaccinated had significantly lower feed intake (FI) at d 21 and feed conversion ratio (FCR) at d 35 compared to control chickens (P < 0.05). Vaccinated chickens showed a significant reduction (P ≤ 0.05) in OPG for E. maxima to nondetectable levels and for all coccidian species at d 42 compared to control chickens. In Exp 2, the chickens vaccinated showed a significant increase in BW, BW gain (BWG) and reduction in FCR on d 27, 35, and 42 (P ≤ 0.05). Vaccinated chickens had significantly lower (P ≤ 0.05) lesion scores for all 3 Eimeria species. Moreover, vaccinated chickens had a reduction in total OPG of 35.50% (P = 0.0739). Studies to evaluate the serological and mucosal immune response are currently being evaluated. This inactivated, orally delivered subunit vaccine offers significant cross-protection to Eimeria spp. and eliminates the needs to treat broilers with live oocysts, enhanced ease of use, and greater biosecurity to producers.


Assuntos
Coccidiose , Eimeria tenella , Eimeria , Doenças das Aves Domésticas , Ração Animal/análise , Animais , Biotecnologia , Galinhas , Coccidiose/prevenção & controle , Coccidiose/veterinária , Doenças das Aves Domésticas/prevenção & controle , Vacinas de Subunidades
7.
Poult Sci ; 100(9): 101369, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34333388

RESUMO

Compounds in microalgae-derived feed ingredients in poultry diets may improve intestinal physiology and immunity to protect against damage induced by physiological and pathogen challenges, but mechanisms are examined sparingly. The study objective was to evaluate changes to intestinal morphology, permeability, and systemic immunity in broilers fed a proprietary microalgae ingredient during 2 separate challenge studies. In study 1, two replicate 28 d battery cage trials used 200 Ross 308 broilers each (n = 400) fed a control diet ± 0.175% algae ingredient. Half of the birds were subjected to a 12 h feed restriction challenge and fluorescein isothiocyanate dextran (FITC-D) intestinal permeability assay on d 28. Study 2 used 800 broilers randomly assigned to the same dietary treatments and housed in floor pens for 42 d. At d 14, intestine and spleen samples were collected from 10 birds/ diet. Half of the remainder was orally inoculated with 10X Coccivac-B52 vaccine in a 2 × 2 factorial treatment design (diet and Eimeria inoculation). The FITC-D assay was conducted at 1, 3, 7, and 14 d post-inoculation (pi) while intestinal and spleen samples were collected at 3, 7, 14, and 28 dpi for histomorphology and flow cytometric immune cell assessment. Study 1 validated intestinal leakage via FITC-D absorbance induced by feed restriction but showed no algae-associated protective effects. In study 2, algae preserved intestinal integrity during coccidiosis (P = 0.04) and simultaneously protected jejunal villus height as early as 7dpi (P < 0.0001), whereas intestinal damage resolution in control birds did not occur until 14 dpi. Algae inclusion increased splenic T cells in unchallenged broilers at d 14 by 29.6% vs. control (P < 0.0001), specifically γδ T cell populations, without impacting performance (P < 0.03). During Eimeria challenge, splenic T cells in algae-fed birds did not show evidence of recruitment to peripheral tissues, while control birds showed a 16.7% reduction compared to their uninoculated counterparts from 3 to 7 dpi (P < 0.0001). This evidence suggests the algae ingredient altered the immune response in a manner that reduced recruitment from secondary lymphoid organs in addition to protecting intestinal physiology.


Assuntos
Coccidiose , Eimeria , Doenças das Aves Domésticas , Ração Animal/análise , Animais , Galinhas , Coccidiose/prevenção & controle , Coccidiose/veterinária , Dieta/veterinária , Suplementos Nutricionais , Imunidade , Intestinos
8.
Parasite ; 28: 61, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34374643

RESUMO

Eimeria spp. cause the disease coccidiosis, which results in chronic wasting of livestock and can lead to the death of the animal. The disease, common worldwide, has caused huge economic losses to the cattle industry in particular. This is the first systematic review and meta-analysis of the prevalence of bovine Eimeria in China. Our search of five databases including PubMed, ScienceDirect, China National Knowledge Infrastructure (CNKI), Chongqing VIP, and Wan Fang for articles published up to February 29, 2020 on the prevalence of Eimeria in cattle in mainland China yielded 46 articles, in which the prevalence of cattle ranged from 4.6% to 87.5%. The rate of bovine Eimeria infection has been decreasing year by year, from 57.9% before 2000 to 25.0% after 2015, but it is still high. We also analyzed the region, sampling years, detection methods, feeding model, seasons, and species of bovine Eimeria. We recommend that prevention strategies should focus on strengthening detection of Eimeria in calves in the intensive farming model.


Assuntos
Doenças dos Bovinos , Coccidiose , Eimeria , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , China/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterinária , Fezes , Prevalência , Fatores de Risco
9.
Poult Sci ; 100(10): 101382, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34403989

RESUMO

Effects of the in ovo administration of vitamin D3 (D3) and 25-hydroxyvitamin D3 (25OHD3) on broiler intestinal lesion incidence, performance and breast meat yield after a coccidiosis challenge were investigated. On each of 10 incubator tray levels, 10 Ross 708 broiler hatching eggs were randomly assigned to each of the following 5 in ovo injection treatments administrated at 18 d of incubation (doi): 1) noninjected; 2) diluent; diluent containing either 3) 2.4 µg D3 (D3), 4) 2.4 µg 25OHD3 (25OHD3), or 5) 2.4 µg D3 + 2.4 µg 25OHD3 (D3+25OHD3). A 50 µL solution volume was injected into each egg using an Inovoject multi-egg injector. Four male chicks were randomly assigned to each of 80 battery cages in each of 2 rooms. Half of the treatment-replicate cages (8) in each room were challenged with a 20× live coccidial vaccine at 14 d of age (doa). One randomly selected bird from each of 4 treatment-replicate cages was scored for coccidiosis lesions before and 2 wk after challenge. Mean BW, BW gain (BWG), feed intake, and feed conversion ratio were determined for all birds from 0 to 14, 15 to 28, and 29 to 41 doa. Carcass weight, and the absolute and relative (% of carcass weight) weights of carcass parts were determined in 3 birds per treatment-replicate cage at 42 doa. Hatchability of live embryonated injected eggs and hatch residue were not affected by treatment. Across challenge treatment, birds in the 25OHD3 treatment group experienced an increase in BWG between 29 and 41 doa when compared to the D3 or diluent-injected birds. Furthermore, pectoralis major muscle percentage tended (P = 0.059) to increase in birds belonging to the 25OHD3 treatment in comparison to birds in the D3 or diluent-injected treatments. These results indicate that regardless of challenge treatment, 2.4 µg of 25OHD3 may increase the BWG and breast meat yield of birds relative to those that only received an injection of commercial diluent.


Assuntos
Galinhas , Coccidiose , Animais , Calcifediol , Colecalciferol , Coccidiose/veterinária , Incidência , Masculino , Carne , Óvulo , Vitamina D/análogos & derivados
10.
Avian Dis ; 65(1): 132-137, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339132

RESUMO

Necrotic enteritis (NE) is a common disease that causes great economic loss to the broiler industry due to mortality and reduced performance. Although Clostridium perfringens (CP) is a necessary component of this disease, coccidia species are a well-defined predisposing factor that exacerbates the condition. Different Eimeria species have been reported to influence NE to different degrees. In a pair of experiments, six different Eimeria species were evaluated in the presence and absence of C. perfringens. Male broiler chicks were housed in battery cages for the duration of both experiments. Feed conversion, body weight gain, and NE mortality were reported in both experiments. Experiment 1 challenged birds with E. maxima, E. acervulina, E. tenella, E. necatrix, and E. brunetti at day 13 and subsequently inoculated birds with CP on days 18, 19, and 20. In the second experiment, E. maxima, E. acervulina, E. tenella, and E. praecox were inoculated on day 15 and challenged with CP on days 17, 18, 19, 20, 21, and 22 of the experiment. In the first experiment, E. acervulina, E. brunetti, E. maxima, and E. necatrix with the addition of CP all stimulated necrotic enteritis mortality. In the second experiment, E. praecox had minimal impact on performance during the challenge (14-23 days) while E. maxima + CP decreased body weight gain and increased mortality compared to the CP alone control. Eimeria maxima had the highest mortality (21.9%) in this experiment followed by E. acervulina (6.3%). The remaining Eimeria with added CP in the second experiment did not induce NE mortality. While the challenge with CP alone did not induce mortality, feed conversion was increased compared to the unchallenged control group. When using isolated Eimeria species in these experiments, disturbances created by E. brunetti and E. maxima resulted in the most-severe challenges. These experiments highlight the NE risk of these species of Eimeria and give insight into how other species interact with the host in a controlled CP challenge model.


Assuntos
Galinhas , Infecções por Clostridium/veterinária , Coccidiose/veterinária , Eimeria/fisiologia , Enterite/veterinária , Necrose/veterinária , Doenças das Aves Domésticas , Animais , Infecções por Clostridium/microbiologia , Clostridium perfringens/fisiologia , Coccidiose/parasitologia , Enterite/microbiologia , Enterite/parasitologia , Masculino , Necrose/microbiologia , Necrose/parasitologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/parasitologia , Distribuição Aleatória , Especificidade da Espécie
11.
Avian Dis ; 65(1): 149-158, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339134

RESUMO

With growing cross-disciplinary collaboration among researchers, it is increasingly important to record detailed methodology to prevent the repetition of preliminary experiments. The purpose of this paper is to explain the development of a coccidiosis challenge model for the investigation of dietary interventions to coccidiosis in broiler chickens. The objectives are to select a dose of mixed species coccidial vaccine and evaluate the suitability (ability to produce a consistent, marked change) of selected response variables important to nutritional studies at different times postinfection (PI). Coccivac-B and Coccivac-B52 (Merck Animal Health) were evaluated as the source of coccidia in three trials. Trials 1 and 2 were randomized complete block designs with four doses (0, 10, 20, or 30 times (×) label dose) of Coccivac-B administered to 12 replicate cages of six birds by repeater pipette (Trial 1) or gavaging needle (Trial 2). Trial 3 used a completely randomized design with 0× or 30× label dose of Coccivac-B52 administered by gavaging needle to six replicate cages of six birds. Birds were gavaged at 15 days of age, and response criteria were evaluated 7 days PI in all trials and again at 10 days PI in Trials 1 and 2. All means are reported in order of increasing coccidia dose with significance accepted at P ≤ 0.05. Broiler performance was not affected by coccidia in Trials 1 or 3 but grew poorer with increasing dose from 0 to 7 days PI in Trial 2 (body weight gain, 465, 421, 388, 365 g; feed to gain, 1.37, 1.47, 1.52, 1.58). As coccidia dose increased, nitrogen corrected apparent metabolizable energy decreased (Trial 1, 3387, 3318, 3267, 3170 kcal kg-1; Trial 2, 3358, 2535, 2422, 2309 kcal kg-1; Trial 3, not measured), while relative weight, length, and content for intestinal sections increased (Trials 1through 3). Gross lesion (duodenum, jejunum/ileum, ceca) and oocyst count scores (jejunum/ileum, ceca) increased with dose; however, gross scoring often suggested infection in unchallenged birds, a finding unsupported by oocyst count scores. At 7 days PI there was no correlation between midgut gross lesion score and midgut oocyst count score (r = 0.06, P = 0.705), but cecal scores were weakly correlated (r = 0.55, P < 0.001). Administering coccidia via repeater pipette (Trial 1) resulted in respiratory distress in some birds, while use of the gavaging needle (Trials 2 and 3) successfully induced intestinal damage in chickens without resulting in coccidia related mortality. Thirty times the label dose at 7 days PI resulted in the greatest number of response variables that produced a consistent, marked change. Therefore, consideration should be given to these conditions when designing future coccidiosis challenge models using vaccines as a source of coccidia.


Assuntos
Galinhas , Coccidiose/veterinária , Eimeria/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Ração Animal/análise , Animais , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Dieta/veterinária , Suplementos Nutricionais , Masculino , Oocistos , Doenças das Aves Domésticas/parasitologia , Vacinas Atenuadas/administração & dosagem
12.
Poult Sci ; 100(10): 101391, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34428644

RESUMO

A series of 6 floor pen trials was conducted to determine the effects of a quillaja and yucca combination product on the performance and carcass traits of growing broiler chickens vaccinated for coccidiosis at the hatchery. In each of the trials graded levels (0, 250, and 500 ppm) of a quillaja and yucca combination (QY) were fed to Ross 708 broilers for the duration of each 42 d test. Trials were arranged in completely randomized block designs involving a minimum of 11 blocks per trial. At the start of each trial, pens contained 55 broilers. In order to provide each bird with an enteric disease challenge, 5 kg commercial broiler litter containing 104 CFU Clostridium perfringens per gram was placed in each pen. In addition, the sporulated oocysts of Eimeria acervulina and E. maxima were added to each pen at the outset of each test. At d 21 of the trials, coccidial lesion scores, mortality and performance were determined; final performance and total mortality were assessed at 42 d. At the completion of each test, 10 birds of average body weight per pen were selected for carcass evaluations; whole and chilled carcass yield were determined, and pre- and post-chill breast measurements were made. A combined analysis of the results of the 6 trials (75 replications per treatment) was used to determine treatment effects and each variable was assessed by linear regression analysis. Results indicated that QY significantly reduced mortality and coccidial lesions scores at d 21 (P < 0.05). Performance was significantly improved by both levels of QY at 21 and 42 d, and significant linear effects were observed for these variables (P < 0.05). All carcass characteristics were significantly improved by QY administration and significant linear responses were observed for each carcass variable (P < 0.05). These results indicate that by reducing intestinal disease challenge, QY provided linear improvements in performance. In addition, QY positively affected carcass parameters as each variable responded linearly to QY feeding (P < 0.05).


Assuntos
Coccidiose , Eimeria , Doenças das Aves Domésticas , Yucca , Ração Animal/análise , Animais , Galinhas , Coccidiose/prevenção & controle , Coccidiose/veterinária , Dieta , Esterco , Doenças das Aves Domésticas/prevenção & controle , Quillaja
13.
Poult Sci ; 100(8): 101239, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34214749

RESUMO

Avian coccidiosis continues to be one of the costliest diseases of commercial poultry. Understanding the epidemiology of Eimeria species in poultry flocks and the resistance profile to common anticoccidials is important to design effective disease prevention and control strategies. This study examined litter samples to estimate the prevalence and distribution of Eimeria species among broiler farms in 4 geographic regions of Colombia. A total of 245 litter samples were collected from 194 broiler farms across representative regions of poultry production between March and August 2019. The litter samples were processed for oocysts enumeration and speciation after sporulation. End-point polymerase chain reaction (PCR) analysis was conducted to confirm the presence of Eimeria species. Anticoccidial sensitivity was determined with 160 Ross AP males in 5 treatment groups: noninfected, nonmedicated control (NNC), infected, nonmedicated control (INC), infected salinomycin treated (SAL, dose: 66 ppm), infected diclazuril treated (DIC, dose: 1 ppm), and infected methylbenzocuate-Clopidol treated (MET.CLO, dose: 100 ppm), All birds were orally inoculated with 1 × 106 sporulated oocysts using a 1 mL syringe, except for the NNC- group who received 1ml of water.Eimeria spp. were found in 236 (96.3%) out of 245 individual houses, representing 180 (92.8%) out of 194 farms. Eimeria acervulina was the most prevalent species (35.0%) followed by Eimeria tenella (30.9%), Eimeria maxima (20.4%), and other Eimeria spp. (13.6%). However, mixed species infections were common, with the most prevalent combination being mixtures of E. acervulina, E. maxima, E. tenella, and other species in 31.4% of the Eimeria-positive samples. PCR analysis identified E. acervulina, E. maxima, E. tenella, Eimeria necatrix, Eimeria mitis, and Eimeria praecox with variable prevalence across farms and regions. Anticoccidial sensitivity testing of strains of Eimeria isolated from 1 region, no treatment difference (P > 0.05) was observed in final weight (BW), weight gain (BWG) or feed conversion (FCR). For the global resistance index (GI) classified SAL and MET.CLO as good efficacy (85.79 and 85.49, respectively) and DIC as limited efficacy (74.52%). These results demonstrate the ubiquitous nature of Eimeria spp. and identifies the current state of sensitivity to commonly used anticoccidials in a region of poultry importance for Colombia.


Assuntos
Coccidiose , Coccidiostáticos , Eimeria , Doenças das Aves Domésticas , Animais , Galinhas , Coccidiose/tratamento farmacológico , Coccidiose/epidemiologia , Coccidiose/veterinária , Coccidiostáticos/uso terapêutico , Colômbia/epidemiologia , Fazendas , Masculino , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/epidemiologia
14.
Front Cell Infect Microbiol ; 11: 684670, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239816

RESUMO

Bovine neosporosis is currently considered one of the main causes of abortion in cattle worldwide and the outcome of the infection is, in part, determined by Neospora caninum isolate virulence. However, the dam and foetal immune responses associated with this factor are largely unknown. We used a model of bovine infection at day 110 of gestation to study the early infection dynamics (10- and 20-days post-infection, dpi) after experimental challenge with high- and low-virulence isolates of N. caninum (Nc-Spain7 and Nc-Spain1H, respectively). In the present work, dam peripheral cellular immune responses were monitored twice a week from -1 to 20 dpi. At different time points, IFN-γ and IL-4 production was investigated in stimulated dam blood and the percentage of monocytes, NK cells, B cells and T cells (CD4+, CD8+ and γδ) in peripheral blood mononuclear cells (PBMC) were determined by flow cytometry. In addition, maternal iliofemoral lymph nodes and foetal spleen and thymus were collected at 10 and 20 dpi for the study of the same cell subpopulations. Peripheral immune response dynamics were similar after the infection with both isolates, with a significant increase in the percentage of CD4+ T cells at 6 and 9 dpi in PBMC, coincident with the higher levels of IFN-γ and IL-4 release. However, the levels of IFN-γ were significantly higher and an increase in CD8+ T cells at 9, 13 and 20 dpi was observed in the dams infected with Nc-Spain7. Nc-Spain1H infection induced higher IL4 levels in stimulated blood and a higher CD4+/CD8+ ratio in PBMC. The analysis of the maternal iliofemoral lymph node showed a significant enhancement in the percentage of NK, CD4+ and CD8+ T cells for the animals infected with the highly virulent isolate and euthanized at 20 dpi. Regarding the foetal responses, the most remarkable result was an increase in the percentage of monocytes at 20 dpi in the spleen of foetuses from both infected groups, which suggests that foetuses were able to respond to N. caninum infection at mid gestation. This work provides insights into how isolate virulence affects the maternal and foetal immune responses generated against N. caninum, which may influence the course of infection.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Animais , Bovinos , Coccidiose/veterinária , Feminino , Feto , Imunidade Celular , Leucócitos Mononucleares , Gravidez , Virulência
15.
Trop Anim Health Prod ; 53(3): 391, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34224021

RESUMO

Neosporosis is a parasitic disease that causes abortions and economic losses in bovine production systems, but no studies have been found concerning its effect on the Creole cattle breed, Blanco Orejinegro (BON). The aim of this research was to establish the serological status of Colombian BON cattle against Neospora caninum and to determine the factors associated with seropositivity. Blood samples were taken from 363 animals from 13 herds in six states of Colombia, and analyzed by indirect ELISA using a commercial test. Information on sex, herd, generation group, and state was recorded. A survey was carried out with 26 questions related to productive, reproductive, and health factors per herd. A logistic regression analysis was performed and the ORs for significantly associated variables were estimated using the R software. General seropositivity of 73.5% (95% CI 68.6-77.9%) was obtained, and sex, age group, and herd were the variables significantly associated with seropositivity (p < 0.05). For the sex variable, seroprevalence levels of 79.6% (95% CI 74.3-84.1%) were recorded for females and 54.5% (95% CI 43.6-65.1%) for males. Herd seroprevalence varied between 58.3 and 95.8%, and the last generation showed the lowest positivity (51.2%, 95% CI 42.1-60.2%). The inadequate disposal of fetuses was a risk factor, while carrying out serological tests to new animals that enter the herd, the use of new gloves and palpation utensils for each animal, supplementation, and stabling were stated as protective factors. No effect of positivity was found in the last calving interval. The implementation of bovine neosporosis control programs to support breeding and conservation programs of the BON breed in Colombia is recommended.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários , Bovinos , Doenças dos Bovinos/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterinária , Colômbia/epidemiologia , Feminino , Masculino , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
16.
Res Vet Sci ; 139: 59-66, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34252703

RESUMO

This study aimed to evaluate the disease severity and local immune responses in macrophage-depleted chicks with Eimeria tenella. Macrophages were reduced by intraperitoneal injection of a carrageenan solution at 12, 13, and 16 days old, whereas the control group received intraperitoneal phosphate-buffered saline. Both chick groups were orally inoculated with E. tenella sporulated oocysts at 14 days old. Feces were collected daily, which were then quantified for oocysts. The chicks were sacrificed on day 5, and the ceca were collected for histopathological observation. The gene expression levels were measured using real-time quantitative reverse transcription-polymerase chain reaction. Macrophage-depleted chicks have been observed to shed a significantly reduced number of fecal oocysts compared to the infected control group. The parasite burden score in cecum specimens of macrophage-depleted chicks was significantly lower than those of infected control on day 5 after infection. Furthermore, macrophage reduction yielded significantly lower cecum histopathological scores and CD4 expression than those of the infected control group. The expression of interleukin (IL)-18, IL-22, interferon-γ, and inducible nitric oxide synthase was also noted to be significantly upregulated in both infected control and macrophage-depleted chicks compared to uninfected chicks. IL-4, IL-13, IL-17, and perforin expressions were also higher with macrophage depletion than in both control groups. These results suggest that macrophages serve as an invasive gate or a transporting vehicle to the site of first merogony. Furthermore, mononuclear phagocytes may play an important role in local immune responses, thus contributing to parasite development during early E. tenella infection.


Assuntos
Carragenina , Coccidiose , Eimeria tenella , Macrófagos , Oocistos , Doenças das Aves Domésticas , Animais , Ceco , Galinhas , Coccidiose/veterinária , Doenças das Aves Domésticas/parasitologia
17.
Parasitol Res ; 120(8): 2973-2979, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34236530

RESUMO

We detected Eimeria oocysts from Japanese green pheasants (Phasianus versicolor) at a zoo in Osaka, Japan. The oocyst isolates were subspherical or ovoidal shaped and measured 17.2 (range 14.7-20.0) µm in length and 14.8 (13.3-16.7) µm in width with a length/width (L/W) ratio of 1.2 (1.0-1.4) and each had one polar granule. The oocysts lacked a residuum and micropyle. Sporocysts measured 9.8 (6.7-13.3) µm in length and 5.9 (4.7-7.3) µm in width, with a L/W ratio of 1.2 (1.1-1.4). Compared to previously published values, this strain shows morphological similarities with an isolate of E. teetartooimia from ring-necked pheasants from other countries. Phylogenetic analysis of the 18S rRNA and mitochondrial cytochrome c oxidase subunit I genes places the isolate in a clade related to chicken Eimeria spp., such as E. acervulina or E. brunetti. Although further analysis is needed, this information can be helpful for the diagnosis and determination of virulence of Eimeria spp. in pheasants.


Assuntos
Coccidiose , Eimeria , Galliformes , Oocistos , Animais , Coccidiose/veterinária , Eimeria/citologia , Eimeria/genética , Fezes , Galliformes/parasitologia , Japão , Oocistos/citologia , Oocistos/genética , Filogenia
18.
Parasitol Res ; 120(8): 2995-3000, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34292375

RESUMO

Neospora caninum is a major reproductive disease in cattle worldwide. In the Argentinian Humid Pampa, the seroprevalence, incidence of abortions, and economic losses due to neosporosis are considerably higher in dairy than in beef cattle. Despite this, we recently demonstrated that N. caninum subpopulations are indistinctly distributed in both dairy and beef production systems. The association between genotypic characteristics defined by microsatellite analysis and the virulence of the different strains-particularly with regard to the severity and extension of histological lesions-is largely unknown. Herein, we used a morphometric approach to analyze encephalic lesions in 62 bovine fetuses spontaneously infected by N. caninum. Morphometric parameters (average size of focal lesions, number of foci/cm2 and the percentage of the section affected by lesions) were compared according to the N. caninum subpopulations found in our previous microsatellite genotyping analysis, animal biotype (beef versus dairy), and fetal age (second stage of gestation versus third stage). The average size of the lesions differed significantly among fetuses with different gestational ages; however, no significant differences among animal biotypes or genotypic patterns were found. Further research into the genetic, molecular, and husbandry factors that could account for this greater impact in Argentinian dairy herds is needed.


Assuntos
Aborto Animal , Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários , Argentina , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Feminino , Feto/parasitologia , Feto/patologia , Neospora/genética , Neospora/imunologia , Gravidez , Estudos Soroepidemiológicos
19.
Ticks Tick Borne Dis ; 12(5): 101708, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34175736

RESUMO

Cattle fever ticks, Rhipicephalus microplus and R. annulatus have been eradicated from the United States and inspectors from the U.S. Department of Agriculture (USDA), Animal Plant Health Inspection Service (APHIS), Cattle Fever Tick Eradication Program (CFTEP) monitor the quarantine zone along the Texas border to prevent the introduction of livestock carrying cattle fever ticks from Mexico. Stray livestock apprehended by CFTEP in the zone are checked for ticks and tested for infectious disease-causing pathogens but are not evaluated for evidence of infection with tick-borne pathogens. We tested blood samples collected from stray cattle by CFTEP inspectors for evidence of infection with tick-borne pathogens. As a comparison group representing U.S. resident cattle, we tested blood samples that had been sent to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for unrelated testing. Both sets of blood samples were evaluated using the same specific and broad-spectrum PCR assays. For the border cattle the overall prevalence of infection with one or more tick-borne pathogen was 58.5 % (79/135) with many co-infections, including 30 cattle positive for Babesia bovis and/or Babesia bigemina (22.2 %) and 77 cattle positive for Anaplasma marginale (57 %), three of these animals were also positive for Borrelia theileri. No resident cattle represented by the TVMDL samples were infected with either of the Babesia spp., or with Borrelia theileri, but three were positive for Theileria orientalis and 7.3 % (7/96) were positive for A. marginale. These data show that cattle originating in Mexico have a higher prevalence of infection with tick-borne pathogens relative to resident U.S. cattle and specifically, a proportion are infected with bovine Babesia, which is absent from U.S. cattle populations. Consequently, these stray cattle may be a reservoir of tick-borne pathogens and if populations of Boophilus ticks become reestablished in areas where they had previously been eradicated, could pose a significant risk to the U.S. Cattle industry.


Assuntos
Anaplasmose/epidemiologia , Babesiose , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Doenças Transmitidas por Carrapatos/epidemiologia , Anaplasma/isolamento & purificação , Anaplasma marginale/isolamento & purificação , Animais , Vetores Aracnídeos/microbiologia , Vetores Aracnídeos/parasitologia , Babesia/isolamento & purificação , Babesiose/epidemiologia , Borrelia/isolamento & purificação , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Coccidiose/epidemiologia , Reservatórios de Doenças/microbiologia , Reservatórios de Doenças/parasitologia , Vetores de Doenças , México , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/epidemiologia , Rhipicephalus/microbiologia , Rhipicephalus/parasitologia , Texas , Theileria/isolamento & purificação , Theileriose/epidemiologia
20.
Vaccine ; 39(32): 4534-4544, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34176703

RESUMO

The purpose of this study was to evaluate the protective efficacy of a vaccine consisting of recombinant Neospora caninum-cyclophilin (NcCyP) and -profilin (NcPro) in sheep. At 42 d and 21 d prior to mating, adult Dorset ewes were immunized with the rNcCyP-rNcPro vaccine (Group 1) or co-purifying non-recombinant (NR) control vaccine (Group 2). At 90 days post-mating, all immunized ewes and were challenged by intravenous injection with 106Nesopora caninum Illinois tachyzoites (NcTZ). Significant protection (P < 0.05) was observed in Group 1 with 9 out of 13 ewes giving birth to live-born lambs (69.2%), whereas all Group 2 ewes aborted (6/6). Neospora caninum was detected by PCR in both fetal and placental tissues from all Group 2 aborting ewes and in the placental tissues of Group 1 aborting ewes. In contrast, tissues and placentas of Group 1 live-born lambs were Neospora DNA-negative. Immunoreactive Neospora antigens were demonstrated in placentas associated with abortions, but not in tissues of aborted fetuses or those of the live-born lambs and their associated placentas. Anti-NcCyP and anti-NcPro titers were high in sera from Group 1 ewes and were further boosted by challenge infection, resulting in long-lasting (≥14.5 mos.) elevated titers. Lambs born to Group 1 ewes also had high NcCyP and NcPro titers in pre-colostrum sera. Immunofluorescence staining (IFA) of NcTZ with Group 1 post-immunization sera revealed both surface and internal TZ staining, a pattern consistent with that observed with rabbit sera to rNcCyP or rNcPro. Infection of NR-vaccinated ewes produced high but transient anti-NcCyP and anti-NcPro Ab titers. The results indicate that the NcCyP-NcPro vaccine elicited strong anti-N. caninum responses and conferred significant protection against abortion and transplacental transmission of N. caninum TZ in sheep.


Assuntos
Aborto Induzido , Coccidiose , Neospora , Doenças dos Ovinos , Animais , Anticorpos Antiprotozoários , Coccidiose/prevenção & controle , Coccidiose/veterinária , Ciclofilinas , Feminino , Placenta , Gravidez , Profilinas , Coelhos , Ovinos , Doenças dos Ovinos/prevenção & controle , Vacinação
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