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Vaccines Mar 2022Viral diseases, including avian influenza (AI) and Newcastle disease (ND), are an important cause of morbidity and mortality in poultry, resulting in significant... (Review)
Review
Viral diseases, including avian influenza (AI) and Newcastle disease (ND), are an important cause of morbidity and mortality in poultry, resulting in significant economic losses. Despite the availability of commercial vaccines for the major viral diseases of poultry, these diseases continue to pose a significant risk to global food security. There are multiple factors for this: vaccine costs may be prohibitive, cold chain storage for attenuated live-virus vaccines may not be achievable, and commercial vaccines may protect poorly against local emerging strains. The development of transient gene expression systems in plants provides a versatile and robust tool to generate a high yield of recombinant proteins with superior speed while managing to achieve cost-efficient production. Plant-derived vaccines offer good stability and safety these include both subunit and virus-like particle (VLP) vaccines. VLPs offer potential benefits compared to currently available traditional vaccines, including significant reductions in virus shedding and the ability to differentiate between infected and vaccinated birds (DIVA). This review discusses the current state of plant-based vaccines for prevention of the AI and ND in poultry, challenges in their development, and potential for expanding their use in low- and middle-income countries.
PubMed: 35335110
DOI: 10.3390/vaccines10030478 -
Scientific Reports Jan 2022The composition of gut bacterial communities is strongly influenced by the host diet in many animal taxa. For birds, the effect of diet on the microbiomes has been...
The composition of gut bacterial communities is strongly influenced by the host diet in many animal taxa. For birds, the effect of diet on the microbiomes has been documented through diet manipulation studies. However, for wild birds, most studies have drawn on literature-based information to decipher the dietary effects, thereby, overlooking individual variation in dietary intake. Here we examine how naturally consumed diets influence the composition of the crop and cloacal microbiomes of twenty-one tropical bird species, using visual and metabarcoding-based identification of consumed diets and bacterial 16S rRNA microbiome sequencing. We show that diet intakes vary markedly between individuals of the same species and that literature-based dietary guilds grossly underestimate intraspecific diet variability. Furthermore, despite an effect of literature-based dietary guild assignment of host taxa, the composition of natural diets does not align with crop and cloacal microbiome similarity. However, host-taxon specific gut bacterial lineages are positively correlated with specific diet items, indicating that certain microbes associate with different diet components in specific avian hosts. Consequently, microbiome composition is not congruent with the overall consumed diet composition of species, but specific components of a consumed diet lead to host-specific effects on gut bacterial taxa.
Topics: Animals; Birds; Diet; Eating; Gastrointestinal Microbiome; Microbiota; Tropical Climate
PubMed: 35027664
DOI: 10.1038/s41598-022-04808-9 -
BioMed Research International 2020Defensins are a class of antimicrobial peptides in vertebrates that function as the first line of innate immunity with potent antimicrobial and immunomodulatory...
Defensins are a class of antimicrobial peptides in vertebrates that function as the first line of innate immunity with potent antimicrobial and immunomodulatory activities. Fourteen defensins, namely, avian -defensin 1 to 14 (-14), have been identified in chickens. Before characterizing the role of s in innate immunity during the early development of chickens, we collected tissue segments from the liver, spleen, and gastrointestinal (GI) tract including the esophagus, crop, proventriculus, gizzard, duodenum, jejunum, ileum, cecum, and colon from broilers at days 1, 3, 7, 14, and 28. After RNA isolation and reverse transcription, we determined the expression levels of the 14 genes in these tissues during the first 28 days after hatching by real-time PCR. The results suggested the s were widely expressed in the chicken liver, spleen, and gastrointestinal (GI) tract. Interestingly, we did not detect expressed in the GI tract, even in the liver and spleen. Additionally, s were differentially expressed in the chicken GI tract. and were expressed most abundantly in the proximal GI tract, especially the esophagus and crop. Moreover, , , , and were expressed in an inverted-V pattern with the peak being the observed expression at days 3, 7, or 14 in the chicken spleen, esophagus, duodenum, and cecum. Other s presented biphasic or inverted-V expression patterns in different tissues. The expression levels of all detected s were strengthened after hatching rather than decreasing steadily. Therefore, s were found to be expressed widely in the chicken liver, spleen, and GI tract and their expression levels were primarily up regulated during the early development of chicken, implying the potential essential roles of s in early innate defense and infection resistance of chickens.
Topics: Aging; Animals; Chickens; Digestive System; Organ Specificity; Real-Time Polymerase Chain Reaction; Spleen; beta-Defensins
PubMed: 33490238
DOI: 10.1155/2020/2567861 -
Frontiers in Physiology 2022Physiologically based kinetic (PBK) models facilitate chemical risk assessment by predicting exposure while reducing the need for animal testing. PBK models for mammals...
Physiologically based kinetic (PBK) models facilitate chemical risk assessment by predicting exposure while reducing the need for animal testing. PBK models for mammals have seen significant progress, which has yet to be achieved for avian systems. Here, we quantitatively compare physiological, metabolic and anatomical characteristics between birds and mammals, with the aim of facilitating bird PBK model development. For some characteristics, there is considerable complementarity between avian and mammalian species with identical values for the following: blood hemoglobin and hemoglobin concentrations per unit erythrocyte volume together with relative weights of the liver, heart, and lungs. There are also systematic differences for some major characteristics between avian and mammalian species including erythrocyte volume, plasma concentrations of albumin, total protein and triglyceride together with liver cell size and relative weights of the kidney, spleen, and ovary. There are also major differences between characteristics between sexually mature and sexually immature female birds. For example, the relative weights of the ovary and oviduct are greater in sexually mature females compared to immature birds as are the plasma concentrations of triglyceride and vitellogenin. Both these sets of differences reflect the genetic "blue print" inherited from ancestral archosaurs such as the production of large eggs with yolk filled oocytes surrounded by egg white proteins, membranes and a calciferous shell together with adaptions for flight in birds or ancestrally in flightless birds.
PubMed: 35450159
DOI: 10.3389/fphys.2022.858386 -
The Yale Journal of Biology and Medicine Jun 2018With the phasing out of routine use of antibiotics in animal agriculture, interest has grown for the need to develop feed supplements that augment commercial poultry... (Review)
Review
With the phasing out of routine use of antibiotics in animal agriculture, interest has grown for the need to develop feed supplements that augment commercial poultry performance and provide food safety benefits. From a food safety perspective, alternative feed supplements can be broadly categorized as either agents which reduce or eliminate already colonized foodborne pathogens or prevent colonization of incoming pathogens. Prebiotics are considered preventative agents since they select for gastrointestinal microbiota which not only benefits the host but can serve as a barrier to pathogen colonization. In poultry, prebiotics can elicit both indirect effects on the bird by shifting the composition and fermentation patterns of the gastrointestinal microbiota or directly by influencing host systems such as immune responses. Generation of short chain fatty acids is believed to be a primary inhibitory mechanism against pathogens when prebiotics are fermented by gastrointestinal bacteria, but other mechanisms such as interference with attachment can occur as well. While most of the impact of the prebiotic is believed to occur in the lower parts of the bird gastrointestinal tract, particularly the ceca, it is possible that some microbial hydrolysis could occur in upper sections such as the crop. Development of next generation sequencing has increased the resolution of identifying gastrointestinal organisms that are involved in metabolism of prebiotics either directly or indirectly. Novel sources of non-digestible oligosaccharides such as cereal grain brans are being explored for potential use in poultry to limit establishment. This review will cover the current applications and prospects for use of prebiotics in poultry to improve performance and limit pathogens in the gastrointestinal tract.
Topics: Animals; Food Safety; Gastrointestinal Microbiome; Gastrointestinal Tract; Poultry; Prebiotics
PubMed: 29955220
DOI: No ID Found -
Toxics Nov 2023Microplastic pollution has become a global concern, with potential negative impacts on various ecosystems and wildlife species. Among these species, ducks () are...
Microplastic pollution has become a global concern, with potential negative impacts on various ecosystems and wildlife species. Among these species, ducks () are particularly vulnerable due to their feeding habits and proximity to aquatic environments contaminated with microplastics. The current study was designed to monitor microplastic (MP) pollutants in the freshwater ecosystem of the Panjkora River, Lower Dir, Pakistan. A total of twenty (20) duck samples were brought up for four months and 13 days on the banks of the river, with no food intake outside the river. When they reached an average weight of 2.41 ± 0.53 kg, all samples were sacrificed, dissected, and transported in an ice box to the laboratory for further analysis. After sample preparation, such as digestion with 10% potassium hydroxide (KOH), density separation, filtration, and identification, the MP content was counted. A total of 2033 MP particles were recovered from 20 ducks with a mean value of 44.6 ± 15.8 MPs/crop and 57.05 ± 18.7 MPs/gizzard. MPs detected in surface water were 31.2 ± 15.5 MPs/L. The major shape types of MPs recovered were fragments in crop (67%) and gizzard (58%) samples and fibers in surface water (56%). Other types of particles recovered were fibers, sheets, and foams. The majority of these detected MP particles were in the size range of 300-500 µm (63%) in crops, and 50-150 µm (55%) in gizzards, while in water samples the most detected particles were in the range of 150-300 µm (61%). Chemical characterization by FTIR found six types of polymers. Low-density polyethylene (LDPE) had the greatest polymer detection rate (39.2%), followed by polyvinyl chloride (PVC) (28.3%), high-density polyethylene (HDPE) (22.7%), polystyrene (6.6%), co-polymerized polypropylene (2.5%), and polypropylene homopolymer (0.7%). This study investigated the presence of microplastics in the crops and gizzards of ducks, as well as in river surface water. The results revealed the significant and pervasive occurrence of microplastics in both the avian digestive systems and the surrounding water environment. These findings highlight the potential threat of microplastic pollution to wildlife and ecosystems, emphasizing the need for further research and effective mitigation strategies to address this pressing environmental concern.
PubMed: 38133373
DOI: 10.3390/toxics11120972 -
Frontiers in Microbiology 2023The protozoan parasite is the most common cellular sexually transmitted disease in humans, and the closely related species is an avian parasite of ecological and...
INTRODUCTION
The protozoan parasite is the most common cellular sexually transmitted disease in humans, and the closely related species is an avian parasite of ecological and economic importance. Phylogenetic evidence suggests arose during bird to human transmission of a -like ancestor. shares a strong clinical association with the independent sexually transmitted pathogen (formerly ) , and the uncultured bacterium " Malacoplasma (formerly ) girerdii," with the latter association being an order of magnitude stronger. Both bacterial species have been shown to profoundly influence growth, energy production and virulence-associated mechanisms.
METHODS
Evidence for a novel sp. was discovered by Illumina metatranscriptomics sequencing of the -infected pigeon mouth. We leveraged published 16S rDNA profiling data from digestive tract of 12 healthy and 24 -infected pigeons to investigate association between the novel sp. and . We utilised Illumina metagenomics sequencing targeted to pigeon oral and crop samples infected with the novel sp. to generate its full-length genome sequence. Sequence similarity network analysis was used to compare annotated proteins from the novel sp. with a range of other related species.
RESULTS
Here we present evidence for a novel species, related to " M. girerdii," that is strongly associated with in the upper digestive tract of domestic pigeons. Analysis of the genome sequence revealed gene features apparently specific to a -symbiotic lineage.
DISCUSSION
These data support a model of long-term association between and spp. that has been conserved across diversification of the lineage and the host species barrier from birds to human.
PubMed: 37808290
DOI: 10.3389/fmicb.2023.1242275 -
Ecology and Evolution Jul 2022Varied strategies to alleviate the loss of farmland biodiversity have been tested, yet there is still insufficient evidence supporting their effectiveness, especially...
Varied strategies to alleviate the loss of farmland biodiversity have been tested, yet there is still insufficient evidence supporting their effectiveness, especially when considering phylogenetic and functional diversity alongside traditional taxonomic diversity metrics. This conservation challenge is accentuated in the Afrotropics by the rapid agricultural expansion and intensification for the production of cash crops and by a comparative lack of research. In this study, we assessed how farming practices influence avian phylogenetic and functional diversity. We conducted point-count surveys to assess avian diversity in monocultures of tea and mixed crop farming systems surrounding the Nyungwe rainforest in south-west Rwanda, allowing us to investigate the drivers of avian diversity at farm level. Species composition was found to be moderately different between farm types, with mixed crop farms supporting higher phylogenetic diversity than tea plantations. There were no significant seasonal differences in species composition, functional or phylogenetic diversity. Overall, functional diversity did not differ between farm types, but the dispersion of trophic-related traits was significantly higher in mixed crop farms. Both functional and phylogenetic diversity were influenced by floristic diversity, vegetation height, tree number, and elevation to varying degrees. Our results also (i) highlight the role of farmland heterogeneity (e.g., crop species composition, height, and tree cover extent) in encouraging avian functional and phylogenetic diversity in the Afrotropics and (ii) indicate that the generally negative biodiversity impacts of monoculture agriculture can be partially alleviated by extensive agroforestry with an emphasis on indigenous tree species.
PubMed: 35822114
DOI: 10.1002/ece3.9024 -
Poultry Science Mar 2020The present study was carried out to investigate the changes in amino acid (AA) contents of crop milk and plasma and mRNA abundance of AA transporters and AA...
The profiling of amino acids in crop milk and plasma and mRNA abundance of amino acid transporters and enzymes related to amino acid synthesis in the crop tissue of male and female pigeons during incubation and chick-rearing periods.
The present study was carried out to investigate the changes in amino acid (AA) contents of crop milk and plasma and mRNA abundance of AA transporters and AA synthesis-related enzymes in the crop tissue of male and female pigeons during incubation and chick-rearing periods. Forty-two pairs of adult White King pigeons with 2 fertile eggs per pair were randomly divided into 7 groups by different breeding stages. The AA content of crop milk decreased from day 1 (R1) to day 25 (R25) of chick rearing (P < 0.05). In both male and female adult pigeons, the contents of Thr, Leu, Val, His, Asp, and Pro in plasma increased to maximum levels on R25. Parental sex effect and interaction between stage and sex were observed in the AA contents of pigeon plasma (P < 0.05). For AA transporters, the mRNA abundances of SNAT2, ASCT1, LAT1, and yLAT2 in the male crops reached the highest value on day 17 of incubation (I17), and the peak mRNA levels of PAT-1, xCT, bAT, and CAT1 were found on R7 (P < 0.05). In females, the abundances of ASCT1, BAT1, asc-1, and CAT1 mRNA peaked on R1, whereas the maximum levels of LAT1, PAT-1, bAT, and yLAT2 were observed on R7. For enzymes involved in AA synthesis, the highest gene expressions of glutamate dehydrogenase 1, acetolactate synthase in both parent pigeons, and L-threonine 3-dehydrogenase in female pigeon crops were attained on I17. The expressions of ornithine-δ-aminotransferase, glutamic-oxal(o)acetic transaminase 1, glutamic-oxal(o)acetic transaminase 2, asparagine synthetase, serine hydroxymethyltransferase 2, and glutamic-pyruvic transaminase 2 in both sexes and argininosuccinate lyase and L-threonine 3-dehydrogenase in males were the highest on R1. In conclusion, AA used for pigeon crop milk formation may originate from plasma and intracellular synthesis. The genes involved in AA transport and synthesis varied significantly with sexual effects, indicating that other factors should be considered in future explorations of the mechanism of protein formation in crop milk.
Topics: Amino Acid Transport Systems; Amino Acids; Animals; Avian Proteins; Columbidae; Crop, Avian; Female; Gene Expression; Male; Maternal Behavior; Paternal Behavior; RNA, Messenger
PubMed: 32115035
DOI: 10.1016/j.psj.2019.10.057 -
PloS One 2022The avian influenza virus (AIV) causes significant economic losses by infecting poultry and occasional spillover to humans. Backyard farms are vulnerable to AIV... (Observational Study)
Observational Study
BACKGROUND
The avian influenza virus (AIV) causes significant economic losses by infecting poultry and occasional spillover to humans. Backyard farms are vulnerable to AIV epidemics due to poor health management and biosecurity practices, threatening rural households' economic stability and nutrition. We have limited information about the risk factors associated with AIV infection in backyard poultry in Bangladesh. Hence, we conducted a cross-sectional survey comprising epidemiological and anthropological investigations to understand the poultry rearing practices and risk factors of AIV circulation among backyard poultry in selected rural communities.
METHODS
We sampled 120 poultry from backyard farms (n = 30) of the three selected communities between February 2017 and January 2018. We tested swab samples for the matrix gene (M gene) followed by H5, H7, and H9 subtypes using real-time reverse transcriptase-polymerase chain reaction (rRT-PCR). We applied multivariable logistic regression for risk factor analysis. Furthermore, we conducted an observational study (42 hours) and informal interviews (n = 30) with backyard farmers to record poultry-raising activities in rural communities.
RESULTS
We detected that 25.2% of the backyard poultry tested positive for AIV, whereas 5% tested positive for H5N1 and 10.8% tested positive for H9N2. Results showed that scavenging in both household garden and other crop fields has higher odds of AIV than scavenging in the household garden (AOR: 24.811; 95% CI: 2.11-292.28), and keeping a cage inside the house has higher odds (AOR:14.5; 95% CI: 1.06-198.51) than keeping it in the veranda, cleaning the cage twice a week or weekly has a higher risk than cleaning daily (AOR: 34.45; 95% CI: 1.04-1139.65), dumping litter or droppings (AOR: 82.80; 95% CI: 3.91-1754.59) and dead birds or wastage (AOR: 109.92, 95% CI: 4.34-2785.29) near water bodies and bushes have a higher risk than burring in the ground, slaughtering and consuming sick birds also had a higher odd of AIV (AOR: 73.45, 95% CI: 1.56-3457.73) than treating the birds. The anthropological investigation revealed that household members had direct contact with the poultry in different ways, including touching, feeding, slaughtering, and contacting poultry feces. Poultry is usually kept inside the house, sick poultry are traditionally slaughtered and eaten, and most poultry raisers do not know that diseases can transmit from backyard poultry to humans.
CONCLUSIONS
This study showed the circulation of H5N1 and H9N2 virus in backyard poultry in rural communities; associated with species, scavenging area of the poultry, location of the poultry cage, the practice of litter, wastage, droppings, and dead bird disposal, and practice of handling sick poultry. We suggest improving biosecurity practices in backyard poultry and mass awareness campaigns to reduce incidences of AIV in household-level poultry farms in rural communities in Bangladesh.
Topics: Animals; Chickens; Cross-Sectional Studies; Ducks; Humans; Influenza A Virus, H5N1 Subtype; Influenza A Virus, H9N2 Subtype; Influenza in Birds; Poultry; Poultry Diseases; RNA-Directed DNA Polymerase; Risk Factors; Rural Population; Water
PubMed: 36219598
DOI: 10.1371/journal.pone.0275852