Isolation, identification, antibiotic resistance profile and molecular analysis of Ornithobacterium rhinotracheal isolates from turkeys.

BACKGROUND: Ornithobacterium rhinotracheal (ORT) infects numerous birds, particularly chickens and turkeys. ORT is an emerging bacterial pathogen of global concern in the poultry industry. As ORT is rapidly spreading throughout commercial poultry, it requires intensive studies of its epidemiology, diagnostic procedures, molecular typing, virulence genes and antimicrobial resistance. OBJECTIVES: The present study was conducted in isolation and identification of ORT from slaughtered turkeys. METHODS: Cleft palate swabs of 200 were collected from slaughtered turkeys and cultured on blood agar. ORT was characterized using biochemical tests and PCR targeting the ORT 16S rRNA gene. Virulence genes of isolates were determined targeting adenylate kinase (adk), copA and virulence-associated protein D (vapD) genes. Additionally, diversity of ORT isolates was performed by enterobacterial repetitive intergenic consensus (ERIC) and RAPD PCR. Disk diffusion was used to determine the antibiotic sensitivity of the isolates. RESULTS: ORT was identified in 23 (11.5%) samples using both the biochemical tests and PCR. The result of detecting virulence genes showed that all the isolates (23: 100%) had the adk gene, whereas two (8.7%) isolates had the copA gene, and seven (30.43%) isolates had the vapD gene. Molecular typing of isolates revealed 21 different patterns by RAPD PCR assay using M13 primer and 20 distinct patterns by ERIC PCR test. Both ERIC and RAPD PCR were distinctive methods for investigating the genetic diversity of ORT isolates. The antibiotic resistance test showed that 18 (78.26%) isolates were resistant to gentamicin, amikacin, cefazolin, streptomycin and penicillin. All isolates (100%) were resistant to cloxacillin and fosfomycin. CONCLUSIONS: This study showed the prevalence of ORT in turkey and high resistance of this bacterium to many common veterinary antibiotics. Moreover, both ERIC and RAPD PCR are distinctive methods for investigating the genetic diversity of ORT isolates. These data may help monitor antibiotic resistance and typing of ORT in epidemiological studies and serve as the foundation for designing region-specific vaccines for future use.

Analysis of Emerging Variants of Turkey Reovirus using Machine Learning.

Avian reoviruses continue to cause disease in turkeys with varied pathogenicity and tissue tropism. Turkey enteric reovirus has been identified as a causative agent of enteritis or inapparent infections in turkeys. The new emerging variants of turkey reovirus, tentatively named turkey arthritis reovirus (TARV) and turkey hepatitis reovirus (THRV), are linked to tenosynovitis/arthritis and hepatitis, respectively. Turkey arthritis and hepatitis reoviruses are causing significant economic losses to the turkey industry. These infections can lead to poor weight gain, uneven growth, poor feed conversion, increased morbidity and mortality and reduced marketability of commercial turkeys. To combat these issues, detecting and classifying the types of reoviruses in turkey populations is essential. This research aims to employ clustering methods, specifically K-means and Hierarchical clustering, to differentiate three types of turkey reoviruses and identify novel emerging variants. Additionally, it focuses on classifying variants of turkey reoviruses by leveraging various machine learning algorithms such as Support Vector Machines, Naive Bayes, Random Forest, Decision Tree, and deep learning algorithms, including convolutional neural networks (CNNs). The experiments use real turkey reovirus sequence data, allowing for robust analysis and evaluation of the proposed methods. The results indicate that machine learning methods achieve an average accuracy of 92%, F1-Macro of 93% and F1-Weighted of 92% scores in classifying reovirus types. In contrast, the CNN model demonstrates an average accuracy of 85%, F1-Macro of 71% and F1-Weighted of 84% scores in the same classification task. The superior performance of the machine learning classifiers provides valuable insights into reovirus evolution and mutation, aiding in detecting emerging variants of pathogenic TARVs and THRVs.

Pathological and phylogenetic characteristics of fowl AOAV-1 and H5 isolated from naturally infected Meleagris Gallopavo.

BACKGROUND: In this study, we investigated the prevalence of respiratory viruses in four Hybrid Converter Turkey (Meleagris gallopavo) farms in Egypt. The infected birds displayed severe respiratory signs, accompanied by high mortality rates, suggesting viral infections. Five representative samples from each farm were pooled and tested for H5 & H9 subtypes of avian influenza viruses (AIVs), Avian Orthoavulavirus-1 (AOAV-1), and turkey rhinotracheitis (TRT) using real-time RT-PCR and conventional RT-PCR. Representative tissue samples from positive cases were subjected to histopathology and immunohistochemistry (IHC). RESULTS: The PCR techniques confirmed the presence of AOAV-1 and H5 AIV genes, while none of the tested samples were positive for H9 or TRT. Microscopic examination of tissue samples revealed congestion and hemorrhage in the lungs, liver, and intestines with leukocytic infiltration. IHC revealed viral antigens in the lungs, liver, and intestines. Phylogenetic analysis revealed that H5 HA belonged to 2.3.4.4b H5 sublineage and AOAV-1 belonged to VII 1.1 genotype. CONCLUSIONS: The study highlights the need for proper monitoring of hybrid converter breeds for viral diseases, and the importance of vaccination programs to prevent unnecessary losses. To our knowledge, this is the first study that reports the isolation of AOAV-1 and H5Nx viruses from Hybrid Converter Turkeys in Egypt.

Comparing the sensory properties of commercially available animal and plant-based burgers.

The number of plant-based meat products on supermarket shelves around the world has grown in recent years however reproducing the sensory experience of eating meat remains a challenge. This study aims to evaluate the sensory gaps between animal and plant-based meat products, specifically burger-type products, from the Australian market. The sample set of 19 commercially available burgers comprises 8 animal-based burgers prepared using beef, chicken, kangaroo, pork, or turkey and 11 high protein plant-based burgers. Vegetable patties are beyond the scope of this study. A trained sensory panel (n = 14) determined the major differences in aroma, texture, flavor, and aftertaste between meat and meat analogues during oral processing, particularly those that may impact consumer acceptability. The animal-based burgers scored high for meaty (aroma), meaty (flavor), and umami but not legume, vegetative, bitterness, and lingering spice attributes. They also received higher average scores for juiciness, fattiness, and final moistness than the plant-based burgers but scored lower in cohesiveness. The plant-based burgers scored high for legume and bitterness but not meaty (aroma), meaty (flavor), and umami attributes. Improving current products and designing new products with desirable sensory properties will enhance consumer acceptability and reinforce recent growth in the plant-based meats market.

Genetic architecture of white striping in turkeys (Meleagris gallopavo).

White striping (WS) is a myopathy of growing concern to the turkey industry. It is rising in prevalence and has negative consequences for consumer acceptance and the functional properties of turkey meat. The objective of this study was to conduct a genome-wide association study (GWAS) and functional analysis on WS severity. Phenotypic data consisted of white striping scored on turkey breast fillets (N = 8422) by trained observers on a 0-3 scale (none to severe). Of the phenotyped birds, 4667 genotypic records were available using a proprietary 65 K single nucleotide polymorphism (SNP) chip. The SNP effects were estimated using a linear mixed model with a 30-SNP sliding window approach used to express the percentage genetic variance explained. Positional candidate genes were those located within 50 kb of the top 1% of SNP windows explaining the most genetic variance. Of the 95 positional candidate genes, seven were further classified as functional candidate genes because of their association with both a significant gene ontology and molecular function term. The results of the GWAS emphasize the polygenic nature of the trait with no specific genomic region contributing a large portion to the overall genetic variance. Significant pathways relating to growth, muscle development, collagen formation, circulatory system development, cell response to stimulus, and cytokine production were identified. These results help to support published biological associations between WS and hypoxia and oxidative stress and provide information that may be useful for future-omics studies in understanding the biological associations with WS development in turkeys.

Development of a Multiplex PCR Assay for Rapid Differentiation of Fowlpox and Pigeonpox Viruses.

The aim of this study was to develop a multiplex PCR assay capable of rapidly differentiating two major Avipoxvirus (APV) species, Fowlpox virus (FWPV) and Pigeonpox virus (PGPV), which cause disease in bird species. Despite the importance of a rapid differentiation assay, no such assay exists that can differentiate the APV species without sequencing. To achieve this, species-specific target DNA fragments were selected from the fpv122 gene of FWPV and the HM89_gp120 gene of PGPV, which are unique to each genome. Nine samples collected from unvaccinated chickens, pigeons, and a turkey with typical pox lesions were genetically identified as FWPV and PGPV. The designed primers and target DNA fragments were validated using in silico analyses with the nucleotide Basic Local Alignment Search Tool. The multiplex PCR assay consisted of species-specific primers and previously described PanAPV primers (genus-specific) and was able to differentiate FWPV and PGPV, consistent with the phylogenetic outputs. This study represents the first successful differentiation of FWPV and PGPV genomes using a conventional multiplex PCR test. This assay has the potential to facilitate the rapid diagnosis and control of APV infections.

Desarrollo de un ensayo de PCR múltiple para la diferenciación rápida de los virus de la viruela aviar y la viruela de paloma. El objetivo de este estudio fue desarrollar un ensayo de PCR múltiple capaz de diferenciar rápidamente dos especies principales de Avipoxvirus (APV) (viruela del pollo), el Fowlpox virus (FWPV) y el Pigeonpox virus (PGPV), (viruela de la gallina), que causan enfermedades en especies de aves. A pesar de la importancia de un ensayo de diferenciación rápida, no existe ningún ensayo que pueda diferenciar las especies de APV sin secuenciación. Para lograr esto, se seleccionaron fragmentos blanco de ADN específicos de especie del gene fpv122 de FWPV y el gene HM89_gp120 de Pigeonpox virus, que son únicos para cada genoma. Nueve muestras recolectadas de pollos, palomas y un pavo que no fueron vacunados con lesiones típicas de la viruela se identificaron genéticamente como FWPV y PGPV. Los iniciadores diseñados y los fragmentos de ADN blanco se validaron mediante análisis in silico mediante la herramienta de búsqueda de alineación local básica de nucleótidos (BLAST). El ensayo de PCR múltiple consistió en iniciadores específicos de especie y cebadores PanAPV previamente descritos (específicos de género) y fue capaz de diferenciar entre Fowlpox virus y Pigeonpox virus, de acuerdo con los resultados filogenéticos. Este estudio representa la primera diferenciación exitosa de los genomas de Fowlpox virus y Pigeonpox virus utilizando una prueba de PCR múltiple convencional. Este ensayo tiene el potencial de facilitar el diagnóstico rápido y el control de las infecciones por Avipoxvirus.

Immunization of turkeys with Clostridium septicum alpha toxin-based recombinant subunit proteins can confer protection against experimental Clostridial dermatitis.

Clostridial dermatitis (CD), caused by Clostridium septicum, is an emerging disease of increasing economic importance in turkeys. Currently, there are no effective vaccines for CD control. Here, two non-toxic domains of C. septicum alpha toxin, namely ntATX-D1 and ntATX-D2, were identified, cloned, and expressed in Escherichia coli as recombinant subunit proteins to investigate their use as potential vaccine candidates. Experimental groups consisted of a Negative control (NCx) that did not receive C. septicum challenge, while the adjuvant-only Positive control (PCx), ntATX-D1 immunization (D1) and ntATX-D2 immunization (D2) groups received C. septicum challenge. Turkeys were immunized subcutaneously with 100 µg of protein at 7, 8 and 9 weeks of age along with an oil-in-water nano-emulsion adjuvant, followed by C. septicum challenge at 11 weeks of age. Results showed that while 46.2% of birds in the PCx group died post-challenge, the rate of mortality in D1- or D2-immunization groups was 13.3%. The gross and histopathological lesions in the skin, muscle and spleen showed that the disease severity was highest in PCx group, while the D2-immunized birds had significantly lower lesion scores when compared to PCx. Gene expression analysis revealed that PCx birds had significantly higher expression of pro-inflammatory cytokine genes in the skin, muscle and spleen than the NCx group, while the D2 group had significantly lower expression of these genes compared to PCx. Peripheral blood cellular analysis showed increased frequencies of activated CD4+ and/or CD8+ cells in the D1 and D2-immunized groups. Additionally, the immunized turkeys developed antigen-specific serum IgY antibodies. Collectively, these findings indicate that ntATX proteins, specifically the ntATX-D2 can be a promising vaccine candidate for protecting turkeys against CD and that the protection mechanisms may include downregulation of C. septicum-induced inflammation and increased CD4+ and CD8+ cellular activation.

Geographical Expansion of Avian Metapneumovirus Subtype B: First Detection and Molecular Characterization of Avian Metapneumovirus Subtype B in US Poultry.

Avian metapneumovirus (aMPV), classified within the Pneumoviridae family, wreaks havoc on poultry health. It typically causes upper respiratory tract and reproductive tract infections, mainly in turkeys, chickens, and ducks. Four subtypes of AMPV (A, B, C, D) and two unclassified subtypes have been identified, of which subtypes A and B are widely distributed across the world. In January 2024, an outbreak of severe respiratory disease occurred on turkey and chicken farms across different states in the US. Metagenomics sequencing of selected tissue and swab samples confirmed the presence of aMPV subtype B. Subsequently, all samples were screened using an aMPV subtype A and B multiplex real-time RT-PCR kit. Of the 221 farms, 124 (56%) were found to be positive for aMPV-B. All samples were negative for subtype A. Six whole genomes were assembled, five from turkeys and one from chickens; all six assembled genomes showed 99.29 to 99.98% nucleotide identity, indicating a clonal expansion event for aMPV-B within the country. In addition, all six sequences showed 97.74 to 98.58% nucleotide identity with previously reported subtype B sequences, e.g., VCO3/60616, Hungary/657/4, and BR/1890/E1/19. In comparison to these two reference strains, the study sequences showed unique 49-62 amino acid changes across the genome, with maximum changes in glycoprotein (G). One unique AA change from T (Threonine) to I (Isoleucine) at position 153 in G protein was reported only in the chicken aMPV sequence, which differentiated it from turkey sequences. The twelve unique AA changes along with change in polarity of the G protein may indicate that these unique changes played a role in the adaptation of this virus in the US poultry. This is the first documented report of aMPV subtype B in US poultry, highlighting the need for further investigations into its genotypic characterization, pathogenesis, and evolutionary dynamics.

Inhibition of Listeria monocytogenes and Clostridium botulinum in Uncured Shredded Pork and Turkey Packaged Under Reduced Oxygen Conditions.

Cooked, uncured meat products packaged under reduced oxygen packaging conditions require the control of anaerobic and facultative anaerobic pathogens if they are held at temperatures greater than 3°C at retail or consumer level. The objective of this study was to determine the inhibition of Listeria monocytogenes and Clostridium botulinum in cooked, uncured shredded turkey and pork formulated with synthetic or clean-label antimicrobials. Treatments of shredded meat products were prepared with or without antimicrobials using turkey thigh or breast that were cooked to 85°C, shredded, and chilled before inoculation with the target pathogen. L. monocytogenes inoculated samples were stored at 7.2°C, whereas C. botulinum samples were stored at 12.8°C; triplicate samples were assayed every 2 weeks. In the first set of experiments, L. monocytogenes populations increased 2 to 3 logs within 2 weeks of storage at 7.2°C in both meat control treatments without antimicrobials and in pork with 4% lactate-diacetate blend (LD). A 1-log increase was observed in turkey with 4% LD and Pork with 2% cultured dextrose-vinegar-rosemary (CDVR) under the same storage conditions; a 1-log increase was observed in turkey with CDVR at 4 weeks. The second set of experiments tested the effect of pH reduction (to less than 5.5 by the addition of 0.5% citric acid) in combination with 2% CDVR when added to the brine precook or postcook during shredding. Populations of L. monocytogenes increased 4-log within 2 and 4 weeks at 7.2°C for the control turkey and pork formulations, respectively. No growth was observed in 12 weeks for any antimicrobial CDVR-CA treatments regardless of how antimicrobial was added. Similarly, botulinum toxin was detected in both control treatments at week 2 at 12.8°C, but no toxicity was observed in either antimicrobial treatment through 12 weeks. These data suggest that a combination of 2% cultured dextrose-vinegar-rosemary extract plus 0.5% citric acid to reduce pH inhibits the growth of L. monocytogenes and toxin production of C. botulinum in uncured shredded turkey and pork products stored under mild temperature abuse conditions for up to 12 weeks in reduced oxygen packaging.

Concurrent Histomonas meleagridis and Hemorrhagic Enteritis Virus Infection in a Turkey Flock with Recurrent History of Blackhead Disease.

Intestinal health is one of the key factors required for the growth and production of turkeys. Histomoniasis (blackhead disease), caused by a protozoan parasite, Histomonas meleagridis, is a reemerging threat to the turkey industry. Increased incidences of histomoniasis have been reported in recent years due to withdrawal of antihistomonas treatments. H. meleagridis affects ceca and causes cecal inflammation and necrosis. H. meleagridis migrates from ceca to the liver and causes liver necrosis, resulting in high mortalities. Ironically, field outbreaks of histomoniasis are not always associated with high mortalities, while low mortalities have also been documented. There are several exacerbating factors associated with high mortality rates in histomoniasis outbreaks, with concurrent infection being one of them. Recurrent histomoniasis outbreaks in a newly constructed barn were documented, and concurrent infection of H. meleagridis and hemorrhagic enteritis virus was confirmed. Currently, neither commercial vaccines nor prophylactic or therapeutic solutions are available to combat histomoniasis. However, there are treatments, vaccines, and solutions to minimize or prevent concurrent infections in turkeys. In addition to implementing biosecurity measures, measures to prevent concurrent infections are critical steps that the turkey industry can follow to reduce mortality rates and minimize the production and economic losses associated with histomoniasis outbreaks.

Infección simultánea por Histomonas meleagridis y el virus de la enteritis hemorrágica en una parvada de pavos con antecedentes recurrentes de enfermedad de la cabeza negra. La salud intestinal es uno de los factores clave necesarios para el crecimiento y producción de los pavos. La histomoniasis (enfermedad de la cabeza negra), causada por un parásito protozoario, Histomonas meleagridis, es una amenaza reemergente para la industria del pavo. En los últimos años se ha informado de un aumento de la incidencia de histomoniasis debido al retiro de los tratamientos con antihistomonas. Histomonas meleagridis afecta los ciegos y causa inflamación y necrosis cecal. Histomonas meleagridis migra desde los ciegos al hígado y causa necrosis hepática, lo que resulta en una alta mortalidad. Irónicamente, los brotes de histomoniasis en el campo no siempre se asocian con una mortalidad elevada, aunque también se han documentado mortalidades bajas. Hay varios factores exacerbantes asociados con altas tasas de mortalidad en los brotes de histomoniasis, siendo la infección concurrente uno de ellos. Se documentaron brotes recurrentes de histomoniasis en un alojamiento avícola recién construido y se confirmó la infección concurrente de H. meleagridis y el virus de la enteritis hemorrágica. Actualmente no se dis-pone de vacunas comerciales ni soluciones profilácticas o terapéuticas para combatir la histomoniasis. Sin embargo, existen tratamientos, vacunas y soluciones para minimizar o prevenir infecciones concurrentes en los pavos. Además de implementar medidas de bioseguridad, las medidas para prevenir infecciones concurrentes son pasos críticos que la industria del pavo puede seguir para reducir las tasas de mortalidad y minimizar las pérdidas económicas y de producción asociadas con los brotes de histomoniasis.

Slatted floor reduces the welfare and increases the foot pad dermatitis and growth performance of Turkeys under Egyptian conditions.

Background: When Turkeys' legscome in contact with their dropping during the growing stage results in footpad dermatitis condition which affects the poult's welfare and productivity. Aim: Our experiment aimed to detect the impact of various bedding substrates on the wellbeing, and performance of growing Turkey under Egyptian conditions. Methods: 180-day-old Turkey poults were allocated into three treatments. In treatment I, the poults [60 each with three replicates (n = 20 birds)] were kept on wood shavings (WS); in the second treatment, the poults were housed on chopped wheat straw (CWS). However, in the third treatment, they kept on a plastic slatted floor (PSF). Results: The greater feed intake and body weight were recorded in poults reared in PSF compared with those kept in other treatments (WS and CWS). Feed conversion ratio did not show any significant difference. The mortality percentage was higher in the PSF group than in the WS one. The frequency of feeding and drinking behavior was higher in poults reared on WS treatment compared with other treatments CWS and PSF. On the other hand, resting behavior showed the highest frequency in poults kept in PSF. Contrary, the lowest frequency of walking behavior was recorded in poults reared in PSF treatment. In addition, the poults kept in WS had a longer tonic immobility reaction period followed by those kept in PSF and CWS. Concerning foot-pad dermatitis, the highest score of 0 was observed in the CWS group, while the highest score of 1 was recorded among poults kept in the WS group. On the other side, the highest score 2, 3, and 4 was observed in the poults reared in the PSF group. Heterophil/Lymphocyte ratio of Turkey poults was higher in PSF. While T3 and T4 concentrations in blood were not affected by using different bedding materials. Conclusion: It is concluded that the slatted floor was good for Turkey producers from the point of performance but, it is the worst from the point of welfare.

Development of real-time PCR assay for quantitative detection of Clostridium septicum.

Cellulitis is an important disease in commercial turkey farms associated with significant economic loss. Although the etiology of cellulitis is not fully elucidated, Clostridium septicum (C. septicum) is one of the main causes of this infectious disease. In this study, we report the development of a quantitative real-time PCR (qRT PCR) assay targeting the alpha-toxin gene (csa), which involves a prior 15-cyle PCR using a nested pair of primers to increase the detection sensitivity. Additionally, the TaqMan probe was employed to increase the target-specificity of the assay. The performance of our nested qRT-PCR assay was evaluated using Clostridium isolates from turkey farms, representing both septicum and non-septicum species, as well as sponge swab samples from turkey farms. Our step-by-step development of the assay showed that the csa gene is a suitable target for specific detection of C. septicum strains and that the inclusion of nested PCR step significantly increased the detection sensitivity of the final qRT PCR assay. The performance of the assay was also validated by a high correlation of the threshold cycle numbers of the qRT PCR assay with the relative abundance of C. septicum read counts in 16S rRNA gene microbiota profiles of the C. septicum-containing samples from turkey farms.

Do flickering lights impact turkey hen behavior, stress, and fear?

Little is known about the effect of light-flicker frequency on poultry, particularly on turkeys. This experiment examined the impact of light-flicker frequency on the behavior, stress, and fear response of Nicholas Select turkey hens reared to 11 wk. The experiment was a randomized complete block design (2 trials), with a one-way factorial analysis evaluating 3 light-flicker frequencies (30, 90, or 195 Hertz; Hz). Birds (n = 3,276 per trial) were housed in 9 individual environmentally controlled rooms (3 replicates per treatment per trial). Data collected included: behavior (4, 8, and 10 wk), incidence of aggressive damage, heterophil-to-lymphocyte ratio, and novel object test (daily d 1-7 and at 4, 8, and 11 wk). Data were analyzed using Proc Mixed (SAS 9.4), with significance declared at P ≤ 0.05. Behavior data are presented as the percentage of time spent performing the behavior. At 4 wk, gentle feather pecking and exploratory behaviors were higher under 195 Hz compared to 30 Hz (P = 0.04 and P = 0.05, respectively). Preening was higher under 90 Hz compared to 30 Hz (P = 0.05). At 8 wk, wing flapping was lowest under 195 Hz (P < 0.01). Gentle feather pecking was higher under 90 and 195 Hz compared to 30 Hz (P = 0.02). Fighting (P = 0.05), aggressive pecking (P = 0.02), and aggressive behaviors (P = 0.01) were lower under 30 Hz compared to 90 Hz. At 10 wk, preening was decreased under 30 Hz (P = 0.03). Incidences of aggressive damage were reduced under 30 Hz compared to 90 Hz (0 d-4 wk; P = 0.01) and under 30 compared to both 90 and 195 Hz (4-8 wk; P = 0.01). At 11 wk, heterophil-to-lymphocyte ratios were lowest under 30 Hz (P = 0.04). The novel object test was unaffected by flicker treatment. In conclusion, many behaviors and the stress and fear responses were unaffected by either visible or non-visible flicker. However, visible flicker (30 Hz) reduced some comfort and exploratory behaviors early in life, and the impact on preening continued to older ages, suggesting minor negative impacts of flicker, particularly early in life.

Gastrointestinal response to the early administration of antimicrobial agents in growing turkeys infected with Escherichia coli.

This study investigated the effects of the early administration of enrofloxacin (E) or doxycycline (D) for the first 5 consecutive days of life, or the continuous administration of the coccidiostat monensin (M) throughout the rearing period on gastrointestinal function in turkeys infected with avian pathogenic Escherichia coli (APEC) in an early or later stage of rearing. Experiment 1 lasted 21 d, and turkeys in groups E, D, and M were infected with APEC on d 15. Experiment 2 lasted 56 d, and it had a factorial arrangement of treatments where birds in groups E, D, and M were infected with APEC on d 15 or d 50. In both experiments, control groups (C) consisted of infected and uninfected birds without antibiotic or coccidiostat administration. On d 21 (Experiment 1) and d 56 (Experiment 2), 8 birds from each subgroup were killed, and the ileal and cecal digesta were sampled to analyze the activity of bacterial enzymes and the concentrations of short-chain fatty acids (SCFA). The experimental treatments did not affect the final body weight or body weight gain of birds. Both experiments demonstrated that APEC contributed to an increase in ammonia levels of the cecal digesta (means from 2 experiments: 0.311 vs. 0.225 mg/g in uninfected birds) and ileal pH (6.79 vs. 6.00) and viscosity (2.43 vs. 1.83 mPa⋅s). Moreover, the E. coli challenge enhanced the extracellular activity of several cecal bacterial enzymes, especially in older turkeys infected with APEC in a later stage of life. The continuous administration of monensin throughout the rearing period resulted in a weaker gastrointestinal response in older birds, compared with the other 2 antibiotics administered for the first 5 d of life. The results of the study are inconclusive as both desirable and undesirable effects of preventive early short-term antibiotic therapy were observed in turkeys, including normalization of ileal viscosity and cecal ammonia concentration (positive effect), and disruption in cecal SCFA production (negative effect).

Are turkey hens affected by light flicker? Effects on performance and health.

Light flicker is a commonly overlooked factor of artificial light sources. This study aimed to determine the impacts of light-flicker frequency on performance, general health, and mortality of 11-wk Nicholas Select turkey hens. The experiment consisted of 2 trials (block) in a randomized complete block design, with 3 light-flicker frequency treatments (30, 90, or 195 Hz). Turkeys (n = 364 per replicate) were randomly placed into environmentally controlled rooms (3 room replicates per treatment per trial). Group body weight (BW) and feed consumption were measured at 0, 4, 8, and 11 wk, and feed efficiency (mortality corrected feed-to-gain; F:Gm) was calculated for each period. Mortality and culls were collected twice daily. Flock uniformity, feather condition and cleanliness, footpad score, and mobility were evaluated at 10 wk (30 birds per room). Litter quality and ocular weight and dimensions were evaluated (11 wk; 4 birds per room). Data were analyzed using Proc Mixed (SAS 9.4) and significance was declared when P < 0.05. At 8 wk, BW was lower under 30 Hz compared to 195 Hz (P = 0.03). Feed consumption was lowest under 30 Hz (0-4 wk and 4-8 wk; P < 0.01). Mortality-corrected F:G was improved under 30 Hz for 8 to 11 wk and 0 to 11 wk (P = 0.05 and P = 0.04, respectively). Total mortality was lower under 195 Hz compared to 30 Hz (P = 0.02). Uniformity, gait score, feather condition, and litter quality were unaffected by flicker. Footpad scores were improved under 90 Hz (P = 0.01), leading to an improved average footpad score (P = 0.02). Feather cleanliness was improved under 90 Hz compared to both 30 Hz and 195 Hz (P<0.01). Right eyeball dimensions differed across lighting treatments, with the dorso-ventral diameter being larger in birds under 30 Hz compared to 195 Hz (P = 0.05). The anterior-posterior size also increased in birds under 30 Hz compared to 90 Hz (P = 0.03). Light flicker impacted turkey hens, with the results demonstrating negative impacts on early growth and changes to ocular characteristics.

Assessment of the Impact of Humic Acids on Intestinal Microbiota, Gut Integrity, Ileum Morphometry, and Cellular Immunity of Turkey Poults Fed an Aflatoxin B1-Contaminated Diet.

A recent study published data on the growth performance, relative weights of the organs of the gastrointestinal tract, liver histology, serum biochemistry, and hematological parameters for turkey poults fed an experimental diet contaminated with aflatoxin B1 (AFB1) and humic acids (HA) extracted from vermicompost. The negative effects of AFB1 (250 ng AFB1/g of feed) were significantly reduced by HA supplementation (0.25% w/w), suggesting that HA might be utilized to ameliorate the negative impact of AFB1 from contaminated diets. The present study shows the results of the remaining variables, as an extension of a previously published work which aimed to evaluate the impact of HA on the intestinal microbiota, gut integrity, ileum morphometry, and cellular immunity of turkey poults fed an AFB1-contaminated diet. For this objective, five equal groups of 1-day-old female Nicholas-700 turkey poults were randomly assigned to the following treatments: negative control (basal diet), positive control (basal diet + 250 ng AFB1/g), HA (basal diet + 0.25% HA), HA + AFB1 (basal diet + 0.25% HA + 250 ng AFB1/g), and Zeolite (basal diet + 0.25% zeolite + 250 ng AFB1/g). In the experiment, seven replicates of ten poults each were used per treatment (n = 70). In general, HA supplementation with or without the presence of AFB1 showed a significant increase (p < 0.05) in the number of beneficial butyric acid producers, ileum villi height, and ileum total area, and a significant reduction in serum levels of fluorescein isothiocyanate-dextran (FITC-d), a marker of intestinal integrity. In contrast, poults fed with AFB1 showed a significant increase in Proteobacteria and lower numbers of beneficial bacteria, clearly suggesting gut dysbacteriosis. Moreover, poults supplemented with AFB1 displayed the lowest morphometric parameters and the highest intestinal permeability. Furthermore, poults in the negative and positive control treatments had the lowest cutaneous basophil hypersensitivity response. These findings suggest that HA supplementation enhanced intestinal integrity (shape and permeability), cellular immune response, and healthier gut microbiota composition, even in the presence of dietary exposure to AFB1. These results complement those of the previously published study, suggesting that HA may be a viable dietary intervention to improve gut health and immunity in turkey poults during aflatoxicosis.

Evaluation of in-feed supplementation of formic acid and thymol as non-antibiotic growth promoters and assessing their effect on antimicrobial resistant E.coli isolated in Turkey.

With the rampant usage of antibiotics as growth promoters (AGPs) in poultry sector, there has been alarming concerns of antimicrobial resistant microbes such as Escherichia coli. Diversification of poultry farming due to consumer demand for safer products with higher protein content, turkey production is gaining popularity. Feed additives such as formic acid (FA) and thymol (TH) are effectively replacing AGPs due to their antimicrobial action. This directed the researchers to find alternatives to antibiotics such as thymol and formic acid because of their strong antimicrobial, anti-oxidative, digestive-stimulating properties. To assess the efficacy of FA and TH as growth promoters and their effect on the antimicrobial resistance (AMR) load, the current study (0-12 weeks) was conducted in CARI VIRAT turkey poults (n = 256; unsexed) those were randomly distributed into eight treatment groups: control(T1), AGP (T2), graded levels of FA (T3 to T5) @ 2.5, 5 and 7.5 ml/kg and TH (T6 to T8) @ 120, 240 and 350 mg/kg. Cloacal swab samples were collected at 0, 4th, 8th and 12th week interval and processed further for isolation, identification and assessment of resistance profile of E. coli. The final body weight, cumulative gain and FCR were significantly (p < 0.05) better for birds under supplementation. The Total plate count (TPC) and coliforms showcased a significant (p < 0.001) reduction in the FA and TH supplement groups as compared to control and AGP group. The resistance profile indicated E. coli isolates from AGP group with significantly (p < 0.001) highest resistivity against antibiotics (viz. chloramphenicol, tetracycline, nalidixic acid, chlortetracycline) while isolates from FA (T5) and TH (T8) groups were the least resistant. blaAmpC gene was significantly (p < 0.001) harbored in T2 isolates whereas least detected in T5 and T8. It was inferred that formic acid (7.5 ml/kg) and thymol (360 mg/kg) can effectively replace AGPs and lower AMR burden in poultry.

Efficacy of powdered alfalfa leaves to ameliorate the toxic effects of aflatoxin B1 in turkey poults.

This experiment was conducted to determine the effect of an adsorbent material based on powdered alfalfa leaves added in the aflatoxin B1 (AFB1)-contaminated diet of turkey poults on production parameters, blood cell count, serum biochemistry, liver enzymes, and liver histology. For this purpose, three hundred and fifty female Nicholas-700 poults were randomly assigned into five treatments: (1) Control, AFB1-free diet; (2) AF, diet contaminated with 250 ng AFB1/g; (3) Alfalfa, AFB1-free diet + 0.5% (w/w) adsorbent; (4) AF+alfalfa, diet contaminated with 250 ng AFB1/g + 0.5% (w/w) adsorbent, and (5) AF+ yeast cell wall (YCW), diet contaminated with 250 ng AFB1/g + 0.5% (w/w) of yeast cell wall (a commercial mycotoxin binder used as reference material). The in vivo efficacy of powdered alfalfa leaves was assessed during a 28-day period. In general, the addition of powdered alfalfa leaves in the AFB1-free diet gave the best performance results (body weight, body weight gain, and feed intake) and improved the values of total protein, glucose, calcium, creatinine, and blood urea nitrogen. Moreover, the addition of powdered alfalfa leaves in the AFB1-contaminated diet enhanced body weight and body weight gain and significantly reduced the feed intake, compared to the AF and AF+YCW groups. Additionally, significant alterations in serum parameters were observed in poults intoxicated with the AFB1, compared to the Control group. Furthermore, typical histopathological lesions were observed in the liver of the AF group, which were significantly ameliorated with the addition of powdered alfalfa leaves. Conclusively, these results pointed out that low inclusion of powdered alfalfa leaves in the contaminated feed counteracted the adverse effects of AFB1 in turkey poults.

Monitoring antimicrobial resistance in Campylobacter isolates of chickens and turkeys at the slaughter establishment level across the United States, 2013-2021.

Foodborne infections with antimicrobial-resistant Campylobacter spp. remain an important public health concern. Publicly available data collected by the National Antimicrobial Resistance Monitoring System for Enteric Bacteria related to antimicrobial resistance (AMR) in Campylobacter spp. isolated from broiler chickens and turkeys at the slaughterhouse level across the United States between 2013 and 2021 were analysed. A total of 1,899 chicken-origin (1,031 Campylobacter coli (C. coli) and 868 Campylobacter jejuni (C. jejuni)) and 798 turkey-origin (673 C. coli and 123 C. jejuni) isolates were assessed. Chicken isolates exhibited high resistance to tetracycline (43.65%), moderate resistance to ciprofloxacin (19.5%), and low resistance to clindamycin (4.32%) and azithromycin (3.84%). Turkey isolates exhibited very high resistance to tetracycline (69%) and high resistance to ciprofloxacin (39%). The probability of resistance to all tested antimicrobials, except for tetracycline, significantly decreased during the latter part of the study period. Turkey-origin Campylobacter isolates had higher odds of resistance to all antimicrobials than isolates from chickens. Compared to C. jejuni isolates, C. coli isolates had higher odds of resistance to all antimicrobials, except for ciprofloxacin. The study findings emphasize the need for poultry-type-specific strategies to address differences in AMR among Campylobacter isolates.

The response of turkeys to dietary balanced protein during two periods of growth.

1. Two experiments were conducted to measure the response of growing turkeys to dietary protein content. In the first, 960 sexed British United Turkey (BUT 6) poults were used to measure the response to balanced protein from 3 to 6 weeks of age. In the second, 1440 sexed BUT and Hybrid Converter poults were raised from 14 to 17 weeks.2. In both experiments, six levels of dietary protein were fed, with feed intake, body and feather weight gain and changes in body composition measured. The levels of protein chosen ranged from 0.53 to 1.2 of the Aviagen requirements for growing turkeys.3. In the first experiment, six poults were sampled from each sex at the start of the experiment for carcass analysis, and four were sampled from each strain and sex in the second. At the end of each experiment, eight poults from each treatment were sampled. Body composition analyses were made on individual defeathered birds.4. Weight gain increased linearly with protein intake in the early period and exponentially in the later period. In both periods, feed intake decreased as protein content reduced.5. In the early period, body lipid content increased from 20.2 to 41.5 g/kg body weight, as dietary protein content decreased, but there was no change in the later period. Efficiency of utilisation of dietary protein declined linearly with an increase in dietary protein content, from 0.87 to 0.46 g/g in the first, and from 0.43 to 0.27 g/g in the later period.6. The inability of the growing turkey to increase feed intake on marginally limiting feeds may have been due to a genetic constraints to store excess energy consumed as body lipid, resulting in the observed decrease in feed intake as dietary protein content is reduced.