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1.
Avian Dis ; 65(1): 138-148, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339133

RESUMO

Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is an important foodborne zoonosis affecting a wide range of hosts, including birds. This study investigated the seroconversion, feed conversion rate, weight gain, and parasite tissue tropism as a function of parasite dose and virulence in turkeys. Twenty-five 4-wk-old female domestic turkeys (Meleagris gallapavo) were intraperitoneally infected with two different strains and two doses (105 and 108 tachyzoites/ml) of T. gondii tachyzoites, resulting in four treatment groups. A fifth group of 10 additional birds was intraperitoneally injected with sterile phosphate-buffered saline as a negative control. All birds remained subclinical except for three birds in the two high-dose groups (108 tachyzoites/ml). Survival rate was 88% (22/25). A 92% seroconversion rate was detected in T. gondii-infected birds using a modified agglutination test. Antibody titers as well as weight gain were related to the dose and strain of T. gondii used. Feed conversion rate was higher in the high-dose groups compared with low-dose and control groups, while weight gain was significantly lower at 14 days postinfection in the group infected with 108 tachyzoites/ml of virulent T. gondii strain. Gross lesions were detected in the pancreas and lungs of only one bird, and histopathologic findings varied depending on strain and dose. The organs that most frequently contained T. gondii DNA as detected by quantitative PCR were the brain and the heart, followed by the bursa of Fabricius and the lungs. This study confirmed that turkeys can be infected with T. gondii, and turkeys can show signs of infection when exposed to high doses. Given the increased practice of outdoor-raised livestock and wildlife consumption, continual experimental infection of T. gondii in wild and domestic animals should be pursued.


Assuntos
Anticorpos Antiprotozoários/imunologia , Formação de Anticorpos , Peso Corporal , Metabolismo Energético , Doenças das Aves Domésticas/parasitologia , Toxoplasma/fisiologia , Toxoplasmose Animal/parasitologia , Perus , Ração Animal , Animais , Feminino , Doenças das Aves Domésticas/imunologia , Toxoplasmose Animal/imunologia
2.
Avian Dis ; 65(1): 46-51, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339121

RESUMO

Avian influenza H9N2 viruses circulate in all types of poultry species, including turkeys, and cause significant losses for the poultry industry in many parts of the word. The aim of this study was to assess the pathogenesis of the Moroccan avian influenza virus (AIV) H9N2 under experimental conditions in turkeys and the protection efficacy of an inactivated commercial vaccine against AIV H9N2. Unvaccinated turkeys showed marked depression sinusitis, respiratory distress characterized by bronchiolar and tracheal rales of moderate severity, and a mortality rate of 50%. Postmortem examinations of dead and euthanatized birds revealed the presence of fibrinous tracheitis and airsacculitis lesions. Vaccination reduced the mortality rate to 20%. Vaccinated birds recovered at day 10 postchallenge, and only 12.5% (1/8) and 37.5% of birds still displayed fibrinous and nonfibrinous airsacculitis lesions, respectively, at day 15 postinoculation. Viral shedding in cloacal and tracheal swabs was lower in vaccinated than in control birds. Although viral RNA was detected in the cloacal swabs of all unvaccinated turkeys at day 3 postinoculation, only 50% of the vaccinated turkeys were positive for virus detection. At day 11 postinoculation, no viral RNA was detected in oropharyngeal swabs of vaccinated turkeys, whereas 40% of the unvaccinated turkeys were still shedding virus.


Assuntos
Vírus da Influenza A Subtipo H9N2/imunologia , Vacinas contra Influenza/imunologia , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Perus , Vacinação/veterinária , Animais , Marrocos , Distribuição Aleatória , Vacinas de Produtos Inativados/imunologia , Eliminação de Partículas Virais
3.
Avian Dis ; 65(1): 59-62, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339123

RESUMO

Here, we report three detections of H7N1 low pathogenicity avian influenza viruses (LPAIV) from poultry in Missouri (n = 2) and Texas (n = 1) during February and March 2018. Complete genome sequencing and comparative phylogenetic analysis suggest that the H7 LPAIV precursor viruses were circulating in wild birds in North America during the fall and winter of 2017 and spilled over into domestic poultry in Texas and Missouri independently during the spring of 2018.


Assuntos
Galinhas , Vírus da Influenza A Subtipo H7N1/isolamento & purificação , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Perus , Animais , Vírus da Influenza A Subtipo H7N1/patogenicidade , Missouri , Texas , Virulência
4.
Avian Dis ; 65(1): 63-66, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339124

RESUMO

Minnesota is the leading state in number of turkeys produced in the United States. Turkey flocks in the field are usually vaccinated several times with live avian orthoavulavirus 1 (AOAV-1) vaccines starting as early as 2 wk of age (WOA). During the years 2018-2019, many turkey flocks were diagnosed with low-virulence AOAV-1 infection around 9 WOA that led to respiratory disease, although they were previously vaccinated. This study was designed to investigate the immunity against AOAV-1 in Minnesota turkey flocks in the field and experimentally after vaccination. We reviewed antibody titers against AOAV-1 from turkey flocks tested by ELISA at Minnesota Poultry Testing Laboratory (n = 1292). Up to 9 WOA, more than 85% of the field flocks tested had unprotective antibody titers against AOAV-1. However, commercial poults at 3 WOA experimentally vaccinated by eye-drop method had an ELISA geometric mean titer of 6011 at 7 WOA. Oropharyngeal virus shedding after vaccination was 10%, 70%, 80%, and 40% at 1, 3, 5, and 7 days postvaccination, respectively. This study demonstrates that experimentally vaccinated turkeys respond very well to AOAV-1 vaccine when properly administered. However, there is clear vaccination failure in the field, where vaccine is commonly administered in drinking water, a method that is more susceptible to failure because of many variables in this procedure. We recommend choosing the most effective method of vaccine administration. Given the high incidence of inadequate immunity induced in commercial turkeys on mass application of live AOAV-1 vaccines in water, alternative application methods and subsequent monitoring of the serologic antibody response must be undertaken to ensure a proper immune response.


Assuntos
Infecções por Avulavirus/veterinária , Avulavirus/efeitos dos fármacos , Doenças das Aves Domésticas/prevenção & controle , Falha de Tratamento , Perus , Vacinação/veterinária , Vacinas Virais/administração & dosagem , Animais , Infecções por Avulavirus/prevenção & controle , Infecções por Avulavirus/virologia , Minnesota , Doenças das Aves Domésticas/virologia
5.
Avian Dis ; 65(1): 171-176, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34339137

RESUMO

Trueperella pyogenes is an opportunistic Gram-positive bacterium that induces purulent lesions and abscesses in cattle, small ruminants, and swine. In birds, T. pyogenes infections have been linked to lameness and osteomyelitis in turkeys (Phasianidae) and hepatic fibriscess in turkeys and pigeons (Columbidae). An 18-mo-old backyard rooster with a history of progressive emaciation was submitted to the California Animal Health and Food Safety (CAHFS) laboratory system. At necropsy, unusual numerous miliary granulomas were identified, primarily in the spleen, but granulomas were also observed in air sacs and lungs. Microscopically, few to moderate numbers of granulomas with giant cells were observed in the spleen, lung, air sacs, and crop composed of necrosis and mixed inflammatory cell inflammation including multinucleated giant cells, fibrin deposition, and fibrosis. Trueperella pyogenes was isolated from the air sacs and trachea. Avibacterium paragallinarum PCR was positive from the tracheal swab. A retrospective analysis of CAHFS data on T. pyogenes between 2000 and 2020 identified 24 cases in avian species: chickens (Gallus gallus domesticus; 16/24), turkeys (5/24), Pekin duck (Anas platyrhynchos domesticus; 1/24), parrot (Psittaciformes; 1/24), and pheasant (Phasianidae; 1/24). Although T. pyogenes infection in birds is rare, the clinical signs and gross lesions might be indistinguishable from avian mycobacteriosis in some cases and should be considered in the differential diagnosis.


Assuntos
Actinomycetaceae/isolamento & purificação , Infecções por Actinomycetales/veterinária , Galinhas , Doenças das Aves Domésticas/diagnóstico , Actinomycetaceae/fisiologia , Infecções por Actinomycetales/diagnóstico , Infecções por Actinomycetales/microbiologia , Animais , California , Patos , Galliformes , Masculino , Doenças das Aves Domésticas/microbiologia , Psittaciformes , Estudos Retrospectivos , Perus
6.
Cryobiology ; 101: 12-19, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34245722

RESUMO

Since turkey reproduction is mainly through artificial insemination, short-term preservation of turkey semen is one of the most important issues in turkey reproduction management. The present study investigates the effects of glutathione (GSH) and trehalose on lipid peroxidation degree and turkey semen quality while being stored at 5 °C for 72 h. To this end, semen samples were collected from 20 turkeys with a weekly frequency for 12 weeks. A glucose-based extender was used to dilute the pooled semen. It was divided into seven equal parts with varying levels of glutathione [0.5, 1 and 2 mM), trehalose [50, 75 and 100] and control [extender without antioxidant]. Subsequently, the divided semen samples were stored at 5 °C for 72 h. Several sperm parameters such as motility and motion parameters, plasma membrane integrity (PMI), plasma membrane functionality, DNA integrity, and oxidative parameters were assessed following storage for 0, 24, 48, and 72 h. The obtained results indicated an improvement in the plasma membrane functionality and DNA integrity, along with the percentages of PMI in GSH-2 mM group in comparison to the control group following storage at 5 °C for 72 h (P ≤ 0.05). It is also notable that the 2 and 1 mM concentrations of GSH increased the spermatozoa motility and motion parameters in comparison to the control group, respectively (P ≤ 0.05). The study results indicated that GSH-2, 1 mM and trehalose- 100 mM concentrations reduced lipid peroxidase levels and increased total antioxidant activity, catalase, superoxide dismutase, and glutathione peroxidase in comparison to the control group (P ≤ 0.05). Our study's data show that improvement of semen parameters and oxidative stress parameters of turkey semen can be improved by glutathione at 2 and 1 mM and trehalose at 75 mM while storing it 5 °C.


Assuntos
Preservação do Sêmen , Sêmen , Animais , Criopreservação/métodos , Glutationa/metabolismo , Masculino , Estresse Oxidativo , Sêmen/metabolismo , Análise do Sêmen , Preservação do Sêmen/veterinária , Motilidade Espermática , Espermatozoides/metabolismo , Trealose/farmacologia , Perus/metabolismo
7.
Poult Sci ; 100(8): 101259, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34233253

RESUMO

Deep pectoral myopathy (DPM) considerably affects the meat quality of commercial poultry, thus representing a challenge to the poultry industry. In this study, we examined the breast meat quality of turkey breeder hens at disposal age affected by different degrees of DPM. Samples were collected from Nicholas turkeys at disposal age (385 d), at an average weight of 12.5 kg, which were reared and slaughtered in the south region of Brazil. The breast was first classified according to the degree of DPM and then samples of the Pectoralis major were collected from birds affected (DPM degrees 2 and 3; n = 20 of each) and nonaffected (normal, absence of lesions; n = 20) by the myopathy. After the affected Pectoralis minor muscle was discarded, the carcasses were released for human consumption by the Federal Inspection Service. The meat affected by the myopathy exhibited color changes (L*, a* and b*) (P < 0.05), especially in the inner surface. Higher (P < 0.05) water-holding capacity, pH, sarcomere length and fat concentration and lower (P < 0.05) shear force and moisture percentage were observed when compared to the normal samples. From this study, can be concluded that the severe condition of deep pectoral myopathy which affects the Pectoralis minor muscle, causes variations in the quality of Pectoralis major muscle of turkey on disposal age. As a raw material, this type of meat has a higher fat content and greater capacity for retaining intracellular water, important attributes to the manufacture of processed products. In this way, the processing is an economically viable alternative to the commercialization of breast meat from birds affected by myopathy.


Assuntos
Doenças Musculares , Perus , Animais , Brasil , Galinhas , Feminino , Carne/análise , Doenças Musculares/etiologia , Doenças Musculares/veterinária , Músculos Peitorais
8.
Genet Sel Evol ; 53(1): 61, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284722

RESUMO

BACKGROUND: Egg production traits are economically important in poultry breeding programs. Previous studies have shown that incorporating genomic data can increase the accuracy of genetic prediction of egg production. Our objective was to estimate the genetic and phenotypic parameters of such traits and compare the prediction accuracy of pedigree-based random regression best linear unbiased prediction (RR-PBLUP) and genomic single-step random regression BLUP (RR-ssGBLUP). Egg production was recorded on 7422 birds during 24 consecutive weeks from first egg laid. Hatch-week of birth by week of lay and week of lay by age at first egg were fitted as fixed effects and body weight as a covariate, while additive genetic and permanent environment effects were fitted as random effects, along with heterogeneous residual variances over 24 weeks of egg production. Predictions accuracies were compared based on two statistics: (1) the correlation between estimated breeding values and phenotypes divided by the square root of the trait heritability, and (2) the ratio of the variance of BLUP predictions of individual Mendelian sampling effects divided by one half of the estimate of the additive genetic variance. RESULTS: Heritability estimates along the production trajectory obtained with RR-PBLUP ranged from 0.09 to 0.22, with higher estimates for intermediate weeks. Estimates of phenotypic correlations between weekly egg production were lower than the corresponding genetic correlation estimates. Our results indicate that genetic correlations decreased over the laying period, with the highest estimate being between traits in later weeks and the lowest between early weeks and later ages. Prediction accuracies based on the correlation-based statistic ranged from 0.11 to 0.44 for RR-PBLUP and from 0.22 to 0.57 for RR-ssGBLUP using the correlation-based statistic. The ratios of the variances of BLUP predictions of Mendelian sampling effects and one half of the additive genetic variance ranged from 0.17 to 0.26 for RR-PBLUP and from 0.17 to 0.34 for RR-ssGBLUP. Although the improvement in accuracies from RR-ssGBLUP over those from RR-PBLUP was not uniform over time for either statistic, accuracies obtained with RR-ssGBLUP were generally equal to or higher than those with RR-PBLUP. CONCLUSIONS: Our findings show the potential advantage of incorporating genomic data in genetic evaluation of egg production traits using random regression models, which can contribute to the genetic improvement of egg production in turkey populations.


Assuntos
Fertilidade , Modelos Genéticos , Característica Quantitativa Herdável , Perus/genética , Animais , Peso Corporal/genética , Ovos/normas , Feminino , Variação Genética , Masculino , Fenótipo , Seleção Artificial , Perus/fisiologia
9.
Poult Sci ; 100(8): 101235, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34214746

RESUMO

Comparative studies designed to investigate the role of glutathione S-transferase (GST) activity on the enzyme catalyzed trapping of aflatoxin B1-8,9-epoxide (AFBO) with glutathione, and the relationship with aflatoxin B1 (AFB1) resistance have not been conducted in poultry. Hepatic cytosolic fractions of chickens, quail, turkeys and ducks were used to measure in vitro the enzymatic parameters maximal velocity (Vmax), Michaelis-Menten constant (Km) and intrinsic clearance (CLint) for GST activity. AFB1 used ranged from 2.0 to 157.5 µM and the AFB1-GSH produced was identified and quantitated by HPLC. Significant differences were found in GST Vmax values, being the highest in chickens, followed by quail, ducks and turkeys. The Km values were also significantly different, with chickens < ducks < turkeys < quail. Chickens had the higher CLint value in contrast to ducks. Differences by sex showed that duck females had a higher CLint value than the turkey and quail, whereas duck males had a CLint close to that of turkey. The ratio "AFBO production /AFB1-GSH production" follows the order duck>turkey>quail>chicken, in agreement with the known poultry sensitivity. The extremely high "AFB1 epoxidation activity/ GST activity" ratio observed in ducks might be the explanation for the development of hepatocellular carcinoma in this species.


Assuntos
Aflatoxina B1 , Glutationa Transferase , Animais , Galinhas , Patos , Feminino , Fígado , Masculino , Aves Domésticas , Codorniz , Perus
10.
Vet Microbiol ; 259: 109155, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34197977

RESUMO

Turkey coronavirus (TCoV) can cause a highly contagious enteric disease in turkeys with severe economic losses in the global turkey industry. To date, no commercial vaccines are available for control of the disease. In the present study, we isolated a field strain (NC1743) of TCoV and evaluated its pathogenicity in specific-pathogen-free (SPF) turkey poults to establish a TCoV disease model. The results showed that the TCoV NC1743 isolate was pathogenic to turkey poults with a minimal infectious dose at 106 EID50/bird. About 50 % of one-day-old SPF turkeys infected with the virus's minimal infectious dose exhibited typical enteric disease signs and lesions from 6 days post-infection (dpi) to the end of the experiment (21 dpi). In contrast, fewer than 20 % of older turkeys (1- or 2-week-old) infected with the same amount of TCoV displayed enteric disease signs, which disappeared after 15-18 dpi. Although all infected turkeys, regardless of age, shed TCoV, the older turkeys shed less virus than the younger birds, and 50 % of the 2-week-old birds even cleared the virus at 21 dpi. Furthermore, the viral infection caused day-old turkeys more body-weight-gain reduction than older birds. The overall data demonstrated that the TCoV NC1743 isolate is a highly pathogenic strain and younger turkeys are more susceptible to TCoV infection than older birds. Thus, one-day-old turkeys infected with the minimal infectious dose of TCoV NC1743 could be used as a TCoV disease model to study the disease pathogenesis, and the TCoV NC1743 strain could be used as a challenge virus to evaluate a vaccine protective efficacy.


Assuntos
Infecções por Coronavirus/veterinária , Coronavirus do Peru/patogenicidade , Doenças das Aves Domésticas/prevenção & controle , Perus/virologia , Animais , Anticorpos Antivirais/sangue , Infecções por Coronavirus/sangue , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Coronavirus do Peru/classificação , Modelos Animais de Doenças , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/virologia , Organismos Livres de Patógenos Específicos
11.
Poult Sci ; 100(9): 101360, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34320453

RESUMO

Under commercial conditions turkeys are housed in large groups in poorly structured environments. This leads to stress and subsequently to pecking and cannibalism. Environmental enrichment is suggested to reduce stress and feather pecking, thus leading to an increase of the overall flock health. However, the effect of increasing age on the use of enrichment elements and on the behavior repertoire as well as its correlation with health parameters has scarcely been studied. Therefore, our objective was to investigate the influence of environmental enrichment on the behavioral repertoire and on health parameters of turkeys. In 3 consecutive trials, female turkeys were housed up to 12 wk either in an unstructured (control group) or enriched environment (EE group) featuring elevated plateaus at different levels ("turkey tree"). Behavior parameters, clinical health, and immune parameters were determined at selected time points. The percentage of birds using the turkey tree increased with age up to 55 to 77% at 22 to 30 d post hatch (dph). Thereafter, the number of birds located on the turkey tree decreased to 25 to 32% at 73 to 79 dph. Feather pecking and fighting was significantly lower in the EE group compared to the control group in 2 and 3 trials, respectively (P < 0.05). The integrity of feathers and integument, scored in the head/neck, wing, and tail regions was repeatedly better in the EE birds compared to control birds at most investigated time points (P < 0.05), suggesting a reduction in stress related aggression by the use of the turkey tree. Head pecking, running and flying activity, foraging, and preening were overall comparable between the EE and the control group (P > 0.05). Humoral immunity as determined by vaccination-induced anti-Newcastle disease virus antibody titers was not affected by the turkey tree use. The flow cytometric evaluation of blood monocyte and T-lymphocyte numbers showed no repeatable difference between control and EE groups. Interestingly, compared to the control groups, EE birds displayed significantly higher numbers of circulating MHC class II+ lymphocytes and lower numbers of thrombocytes at various time points compared to controls (P < 0.05). This study provides clear evidence that environmental enrichment with plateaus not only leads to an altered behavioral repertoire but also modifies some of the investigated immune parameters, implying that EE may have a modulatory effect on turkeys' immunity and overall fitness. Further studies are needed to understand the correlation between behavior and health parameters in birds more closely.


Assuntos
Abrigo para Animais , Perus , Animais , Comportamento Animal , Galinhas , Plumas , Feminino , Contagem de Leucócitos/veterinária
12.
Food Microbiol ; 99: 103800, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119094

RESUMO

A quantitative microbial risk assessment (QMRA) model predicting the listeriosis risk related to the consumption of Ready- To- Eat (RTE) cooked meat products sliced at retail stores in Greece was developed. The probability of illness per serving assessed for 87 products available in the Greek market was found highly related to the nitrite concentration; products having a lower concentration showed a higher risk per serving. The predicted 95th percentiles of the annual listeriosis cases totaled 33 of which 13 cases were <65 years old and 20 cases ≥65 years old. The highest number of cases was predicted for mortadella, smoked turkey, boiled turkey and parizer, which were the most frequently consumed product categories. Two scenarios for assessing potential interventions to reduce the risk were tested: setting a use-by date of 14 days (these products have no use-by date based on current European Union legislation) and improving the temperature control during domestic storage. The two scenarios resulted in a decrease of the 95th and 99th percentiles of the total annual cases by 97% and 88%, respectively.


Assuntos
Fast Foods/microbiologia , Listeria monocytogenes/isolamento & purificação , Produtos da Carne/microbiologia , Animais , Bovinos , Galinhas , Qualidade de Produtos para o Consumidor , Feminino , Contaminação de Alimentos/análise , Contaminação de Alimentos/economia , Contaminação de Alimentos/estatística & dados numéricos , Grécia/epidemiologia , Humanos , Listeria monocytogenes/classificação , Listeria monocytogenes/genética , Listeria monocytogenes/crescimento & desenvolvimento , Listeriose/epidemiologia , Listeriose/microbiologia , Masculino , Produtos da Carne/economia , Medição de Risco , Perus
13.
Poult Sci ; 100(8): 101219, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34166870

RESUMO

Effects of fiber on growth performance, gizzard attributes, ileal digesta viscosity, plasma uric acid (PUA) and excreta characteristics were investigated in broiler chickens (experiment 1) and turkey poults (experiment 2) fed corn or wheat-based diets with or without multienzyme supplement (MES). Fibrous diets were created by adding 10% corn distillers dried grains with solubles or wheat middlings in corn or wheat-based diets, respectively. The MES had main activities of xylanase and ß-glucanase. A total of 960-d old Ross x Ross 708 male chicks and 720-d old male Hybrid toms were allocated to eight grain, fiber and MES combinations to give 6 replicates per combination. In each experiment, birds had free access to feed and water for 28 days. Excreta samples were collected for 3-d prior to the end and on d 28, body weight and feed intake were recorded, birds bled and subsequently necropsied for gastrointestinal samples. There was an interaction (P ≤ 0.036) between grain, fiber and MES in broilers final body weight (FBW) and BW gain (BWG). In this context, high fiber corn diets reduced FBW and BWG and supplementation of MES improved these parameters. Broilers fed corn had a higher (P < 0.05) FBW (1,462 vs. 1,424 g) and BWG (1,416 vs. 1,378 g) than birds fed wheat diets. Broilers fed corn-based diets without fiber diets had a higher ileal viscosity and excreta moisture compared to birds fed wheat-based and high fiber diets. Broilers fed low fiber wheat diets without MES had higher (P < 0.05) PUA concentration compared to birds fed low fiber corn diets without MES. Poults fed wheat diets had a higher (P < 0.05) FBW (1,441 vs. 1,408 g) and BWG (1,376 vs. 1,343 g) than poults fed corn diet. The MES supplementation in corn-based diets rich in fiber increased (P = 0.03) gizzard weight in poults. In conclusion, there were varied growth and physiological responses in broilers and turkey suggesting the need for refining enzyme application for different poultry species.


Assuntos
Galinhas , Zea mays , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Digestão , Masculino , Triticum , Perus
14.
Viruses ; 13(5)2021 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-34065126

RESUMO

The main findings of the post-mortem examination of poultry infected with highly pathogenic avian influenza viruses (HPAIV) include necrotizing inflammation and viral antigen in multiple organs. The lesion profile displays marked variability, depending on viral subtype, strain, and host species. Therefore, in this study, a semiquantitative scoring system was developed to compare histopathological findings across a wide range of study conditions. Briefly, the severity of necrotizing lesions in brain, heart, lung, liver, kidney, pancreas, and/or lymphocytic depletion in the spleen is scored on an ordinal four-step scale (0 = unchanged, 1 = mild, 2 = moderate, 3 = severe), and the distribution of the viral antigen in parenchymal and endothelial cells is evaluated on a four-step scale (0 = none, 1 = focal, 2 = multifocal, 3 = diffuse). These scores are used for a meta-analysis of experimental infections with H7N7 and H5N8 (clade 2.3.4.4b) HPAIV in chickens, turkeys, and ducks. The meta-analysis highlights the rather unique endotheliotropism of these HPAIV in chickens and a more severe necrotizing encephalitis in H7N7-HPAIV-infected turkeys. In conclusion, the proposed scoring system can be used to condensate HPAIV-typical pathohistological findings into semiquantitative data, thus enabling systematic phenotyping of virus strains and their tissue tropism.


Assuntos
Vírus da Influenza A/fisiologia , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/virologia , Tropismo Viral , Animais , Antígenos Virais , Biópsia , Galinhas , Patos , Imuno-Histoquímica , Vírus da Influenza A Subtipo H7N7 , Vírus da Influenza A/classificação , Especificidade de Órgãos , Índice de Gravidade de Doença , Perus
15.
Poult Sci ; 100(7): 101114, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34077846

RESUMO

This study aimed to evaluate the fate and dissemination of Salmonella Reading (SR) in turkeys using an oral gavage challenge model. One hundred twenty-eight-week-old commercial turkey hens were moved from commercial production to research facilities. Upon arrival, a combination of enrofloxacin, 10 mg/kg, and florfenicol, 20 mg/kg, were orally administered sequentially before comingled placement on fresh pine shavings. Turkeys were challenged with 108 cfu SR by oral gavage on d 4 and 7 postplacement. Subsets were subjected to simulated commercial processing on d 14 (n = 40), 21 (n = 40) and 28 (n = 32) postplacement (corresponding to 10, 11, and 12 wk of age). Stifle joint, skin, trachea, crop, lung, liver + spleen (LS), and ceca were aseptically sampled and cultured for Salmonella recovery and serotyping. SR could not be recovered from stifle joint 14 d post inoculation (PI). However, at 14 d PI, recovery of SR were: Skin 80%; crop 75%; LS 67.5%; lungs 60%; and ceca 57.5%. (P < 0.01). Interestingly, the lowest recovery of SR was observed from trachea (40%). At 21 d PI, the highest rate of positive samples to SR were observed in ceca (87.5%) and crop (67.5%). By 28 d PI, SR was only recovered from ceca (75%); crop (43.8%); lung (34.4%); and LS (21.9%). The results of this study confirms that SR is an emerging problem for the turkey industry and immediate measurements to reduce foodborne pathogens such as Salmonella should target all parts of the supply chain and consumer education about food safety.


Assuntos
Doenças das Aves Domésticas , Salmonelose Animal , Salmonella enterica , Animais , Galinhas , Leitura , Sorogrupo , Perus
16.
Poult Sci ; 100(7): 101186, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34089934

RESUMO

Avian metapneumovirus (aMPV) is a viral pathogen that causes respiratory signs and drops in egg production most notably in turkeys but also affects chickens, ducks and other species. Four subgroups (aMPV-A, -B, -C and -D) have been characterized to date, which differ genetically, antigenically and in terms of geographic distribution and host range. Despite the rising awareness towards aMPV, many aspects of its epidemiology are still poorly understood. In this pilot study, a serological survey was carried out to assess the possible circulation of subgroups A, B, and C in intensively raised ducks in Northern Italy. A total of 220 sera from 10 Pekin duck flocks and one mallard flock were collected at slaughter and tested by subgroup-specific aMPV-A, B, and C indirect ELISA assays. None of the tested birds had been vaccinated against aMPV and no symptoms had been reported. No aMPV-A, B or C antibodies were detected in any bird of the Pekin duck flocks, whereas the entire mallard flock tested positive for aMPV-C antibodies. This is the first report of aMPV-C antibodies in ducks in Italy, where only aMPV-B has been reported to circulate in recent years. Further research efforts will be targeted towards the screening of a larger panel of samples, in the hope of obtaining positive samples from which full length genome sequences and infectious viruses can be isolated for virus characterization. Finally, the demonstration of aMPV-C specific antibodies in the serum of all sampled mallards indirectly suggests that this species is readily infected by aMPV-C and supports a possible role of wild anatids as a transmission vector of the virus.


Assuntos
Metapneumovirus , Infecções por Paramyxoviridae , Doenças das Aves Domésticas , Animais , Anticorpos Antivirais , Galinhas , Patos , Itália , Infecções por Paramyxoviridae/veterinária , Projetos Piloto , Perus
17.
Int J Food Microbiol ; 348: 109208, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-33940536

RESUMO

Microbiological spoilage of meat is considered as a process which involves mainly bacterial metabolism leading to degradation of meat sensory qualities. Studying spoilage requires the collection of different types of experimental data encompassing microbiological, physicochemical and sensorial measurements. Within this framework, the objective herein was to carry out a multiblock path modelling workflow to decipher causality relationships between different types of spoilage-related responses: composition of microbiota, volatilome and off-odour profiles. Analyses were performed with the Path-ComDim approach on a large-scale dataset collected on fresh turkey sausages. This approach enabled to quantify the importance of causality relationships determined a priori between each type of responses as well as to identify important responses involved in spoilage, then to validate causality assumptions. Results were very promising: the data integration confirmed and quantified the causality between data blocks, exhibiting the dynamical nature of spoilage, mainly characterized by the evolution of off-odour profiles caused by the production of volatile organic compounds such as ethanol or ethyl acetate. This production was possibly associated with several bacterial species like Lactococcus piscium, Leuconostoc gelidum, Psychrobacter sp. or Latilactobacillus fuchuensis. Likewise, the production of acetoin and diacetyl in meat spoilage was highlighted. The Path-ComDim approach illustrated here with meat spoilage can be applied to other large-scale and heterogeneous datasets associated with pathway scenarios and represents a promising key tool for deciphering causality in complex biological phenomena.


Assuntos
Bactérias/metabolismo , Produtos da Carne/microbiologia , Carne/microbiologia , Compostos Orgânicos Voláteis/análise , Animais , Bactérias/classificação , Microbiologia de Alimentos , Embalagem de Alimentos , Lactococcus/metabolismo , Leuconostoc/metabolismo , Microbiota , Odorantes/análise , Psychrobacter/metabolismo , Perus/microbiologia
18.
Arch Virol ; 166(8): 2285-2289, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34057608

RESUMO

Mesenchymal stromal cells (MSCs) are considered multipotent progenitors with the capacity to differentiate into mesoderm-like cells in many species. The immunosuppressive properties of MSCs are important for downregulating inflammatory responses. Turkey coronavirus (TCoV) is the etiological agent of a poult mortality syndrome that affects intestinal epithelial cells. In this study, poult MSCs were isolated, characterized, and infected with TCoV after in vitro culture. The poult-derived MSCs showed fibroblast-like morphology and the ability to undergo differentiation into mesodermal-derived cells and to support virus replication. Infection with TCoV resulted in cytopathic effects and the loss of cell viability. TCoV antigens and new viral progeny were detected at high levels, as were transcripts of the pro-inflammatory factors INFγ, IL-6, and IL-8. These findings suggest that the cytokine storm phenomenon is not restricted to one genus of the family Coronaviridae and that MSCs cannot always balance the process.


Assuntos
Coronavirus do Peru/fisiologia , Citocinas/metabolismo , Replicação Viral , Animais , Diferenciação Celular , Sobrevivência Celular , Efeito Citopatogênico Viral , Interferon gama/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/virologia , Perus , Regulação para Cima
19.
PLoS One ; 16(4): e0249138, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33822782

RESUMO

Pasteurella multocida is a bacterial pathogen with the ability to infect a multitude of hosts including humans, companion animals, livestock, and wildlife. This study used bioinformatic approaches to explore the genomic diversity of 656 P. multocida isolates and epidemiological associations between host factors and specific genotypes. Isolates included in this study originated from a variety of hosts, including poultry, cattle, swine, rabbits, rodents, and humans, from five different continents. Multi-locus sequence typing identified 69 different sequence types. In-silico methodology for determining capsular serogroup was developed, validated, and applied to all genome sequences, whereby capsular serogroups A, B, D, and F were found. Whole genome phylogeny was constructed from 237,670 core single nucleotide variants (SNVs) and demonstrated an overall lack of host or capsular serogroup specificity, with the exception of isolates from bovine sources. Specific SNVs within the srlB gene were identified in P. multocida subsp. septica genomes, representing specific mutations that may be useful for differentiating one of the three known subspecies. Significant associations were identified between capsular serogroup and virulence factors, including capsular serogroup A and OmpH1, OmpH3, PlpE, and PfhB1; capsular serogroup B and HgbA and PtfA; and capsular serogroup F and PtfA and PlpP. Various mobile genetic elements were identified including those similar to ICEPmu1, ICEhin1056, and IncQ1 plasmids, all of which harbored multiple antimicrobial resistance-encoding genes. Additional analyses were performed on a subset of 99 isolates obtained from turkeys during fowl cholera outbreaks from a single company which revealed that multiple strains of P. multocida were circulating during the outbreak, instead of a single, highly virulent clone. This study further demonstrates the extensive genomic diversity of P. multocida, provides epidemiological context to the various genotyping schemes that have traditionally been used for differentiating isolates, and introduces additional tools for P. multocida molecular typing.


Assuntos
Genes Bacterianos , Pasteurella multocida/genética , Polimorfismo de Nucleotídeo Único , Animais , Proteínas da Membrana Bacteriana Externa/genética , Elementos de DNA Transponíveis , Farmacorresistência Bacteriana , Infecções por Pasteurella/epidemiologia , Infecções por Pasteurella/microbiologia , Pasteurella multocida/isolamento & purificação , Pasteurella multocida/patogenicidade , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Sorogrupo , Perus/microbiologia , Fatores de Virulência/genética
20.
Res Vet Sci ; 136: 602-608, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33895569

RESUMO

The aim of the present study was to characterize the specific binding sites for [N-methyl-3H]-scopolamine ([3H]-NMS), a radioligand for labeling muscarinic acetylcholine receptors (mAChRs), in membranes of four heart chambers obtained from adult male British United Turkey (BUT) Big 6 ("meat-type") and Cröllwitzer ("wild-type") turkeys. MAChR subtypes were examined by inhibiting [3H]-NMS binding with subtype selective non-labelled receptor antagonists. In all left and right atria as well as left and right ventricles of both turkey breeds, the specific [3H]-NMS binding was saturable, reversible and of high affinity (KD range: 0.5-1.0 nM). The maximum receptor density (Bmax) was not significantly different between the four cardiac chambers of BUT Big 6 turkeys, but a significant difference was found between atria and ventricles of Cröllwitzer turkeys. Moreover, significant lower Bmax was found in the atria of Cröllwitzer turkeys than in the atria of BUT Big 6, while the ventricular Bmax was significantly higher. In all cardiac chambers, unlabeled mAChR antagonists competed for specific [3H]-NMS binding sites in a concentration-dependent manner, suggesting the presence of the M3 and M2 receptor subtypes, whereby the latter was the predominant subtype. The presence of the M1 subtype could not be excluded. In conclusion, there was a difference between BUT Big 6 ("meat-type") and Cröllwitzer ("wild-type") turkeys with regard to receptor density in heart chambers with dominant M2 and M3 receptor subtypes.


Assuntos
Miocárdio/metabolismo , Receptores Muscarínicos/biossíntese , Perus/metabolismo , Animais , Átrios do Coração/metabolismo , Ventrículos do Coração/metabolismo , Masculino
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