Browse Items: 294

Parvovirus-Associated Cerebellar Hypoplasia and Hydrocephalus in Day Old Broiler Chickens

Parvovirus-Associated Cerebellar Hypoplasia and Hydrocephalus in Day Old Broiler Chickens.jpg
Cerebellar hypoplasia and hydrocephalus were identified in day old broiler chickens showing nervous signs, impaired mobility, and diarrhea. At postmortem examination, brains of chickens were misshapen and cerebellums were smaller than normal. Microscopically, cerebellar folia were reduced in size and irregularly shaped, and the ventricles were…

New Approach to Delist Highly Pathogenic Avian Influenza Viruses from BSL3+ Select Agents to BSL2 Non-Select Status for Diagnostics and Vaccines

New Approach to Delist Highly Pathogenic Avian Influenza Viruses from BSL3+ Select Agents to BSL2 Non-Select Status for Diagnostics and Vaccines.jpg
Highly pathogenic avian influenza viruses (AIVs) are Select Agents in the United States and are required to be handled in bio-containment level-3 enhanced (BSL3+) facilities. Using a reverse genetics system, we attenuated a highly pathogenic virus, with the goal of making it low pathogenic and having it delisted as a Select Agent so that it could…

A MEQ-Deleted Marek’s Disease Virus Cloned as a Bacterial Artificial Chromosome Is a Highly Efficacious Vaccine

A MEQ-Deleted Marek’s Disease Virus Cloned as a Bacterial Artificial Chromosome Is a Highly Efficacious Vaccine.jpg
The Marek’s disease virus (MDV) induces T-cell tumors in susceptible chickens. Of the 80 to 100 known MDV genes, only the MDV MEQ gene was shown to have transforming properties. Further evidence that MEQ is probably the principal oncogene in MDV came when researchers used overlapping cosmid clones of MDV and demonstrated that deleting MEQ…

Biologic Characterization of Chicken-Derived H6N2 Low Pathogenic Avian Influenza Viruses in Chickens and Ducks

Biologic Characterization of Chicken-Derived H6N2 Low Pathogenic Avian Influenza Viruses in Chickens and Ducks.jpg
Low pathogenic avian influenza H6N2 viruses were biologically characterized by infecting chickens and ducks in order to compare adaptation of these viruses in these species. We examined the clinical signs, virus shedding, and immune response to infection in 4-wk-old white leghorn chickens and in 2-wk-old Pekin ducks. Five H6N2 viruses isolated…

Systemic response to Campylobacter jejuni infection by profiling gene transcription in the spleens of two genetic lines of chickens

Systemic response to Campylobacter jejuni infection by profiling gene transcription in the spleens of two genetic lines of chickens.jpg
Campylobacter jejuni (C. jejuni) is a leading cause of human bacterial enteritis worldwide with poultry products being a major source of C. jejuni contamination. The chicken is the natural reservoir of C. jejuni where bacteria colonize the digestive tract of poultry, but rarely cause symptoms of disease. To understand the systemic molecular…

Gene expression profiling in rMd5- and rMd5Δmeq-infected chickens

Gene expression profiling in rMd5 and rMd5 meq infected chickens.jpg
Marek’s disease (MD) is a lymphoproliferative disorder of domestic chickens caused by a highly contagious and oncogenic α-herpesvirus, Marek’s disease virus (MDV). MD is characterized by bursal–thymic atrophy and rapid onset of T-cell lymphomas that infiltrate lymphoid tissues, visceral organs, and peripheral nerves with severe clinical signs that…

Chromosomal Mapping and Candidate Gene Discovery of Chicken Developmental Mutants and Genome-Wide Variation Analysis of MHC Congenics

Chromosomal Mapping and Candidate Gene Discovery of Chicken Developmental Mutants and Genome-Wide Variation Analysis of MHC Congenics.jpg
The chicken has been widely used in experimental research given its importance to agriculture and its utility as a model for vertebrate biology and biomedical pursuits for over 100 years. Herein we used advanced technologies to investigate the genomic characteristics of specialized chicken congenic genetic resources developed on a highly inbred…

Analysis of global transcriptional responses of chicken following primary and secondary Eimeria acervulina infections

Analysis of global transcriptional responses of chicken following primary and secondary Eimeria acervulina infections.jpg
Characterization of host transcriptional responses during coccidia infections can provide new clues for the development of alternative disease control strategies against these complex protozoan pathogens. Methods: In the current study, we compared chicken duodenal transcriptome profiles following primary and secondary infections with Eimeria…

Marek’s disease virus challenge induced immune-related gene expression and chicken repeat 1 (CR1) methylation alterations in chickens

Marek’s disease virus challenge induced immune-related gene expression and chicken repeat 1 (CR1) methylation alterations in chickens.jpg
Marek’s disease virus (MDV) challenge induces lymphoma in susceptible chickens. Host genes, especially immune related genes, are activated by the virus. DNA methylation is an epigenetic mechanism that governs gene transcription. In the present study, we found that expression of signal transducer and activator of transcription 1 (STAT1) was…

Transcriptional Profiling of MEq-Dependent Genes in Marek’s Disease Resistant and Susceptible Inbred Chicken Lines

Transcriptional Profiling of MEq-Dependent Genes in Marek’s Disease Resistant and Susceptible Inbred Chicken Lines.jpg
Marek’s disease (MD) is an economically significant disease in chickens caused by the highly oncogenic Marek’s disease virus (MDV). Understanding the genes and biological pathways that confer MD genetic resistance should lead towards the development of more disease resistant commercial poultry flocks or improved MD vaccines. MDV mEq, a bZIP…

Integrated Analyses of Genome-Wide DNA Occupancy and Expression Profiling Identify Key Genes and Pathways Involved in Cellular Transformation by a Marek’s Disease Virus Oncoprotein Meq

Integrated Analyses of Genome-Wide DNA Occupancy and Expression Profiling Identify Key Genes and Pathways Involved in Cellular Transformation by a Marek’s Disease Virus Oncoprotein Meq.jpg
Marek’s disease (MD) is an economically significant disease in chickens that is caused by the highly oncogenic Marek’s disease virus (MDV). A major unanswered question is the mechanism of MDV-induced tumor formation. Meq, a bZIP transcription factor discovered in the 1990s, is critically involved in viral oncogenicity, but only a few of its host…

Large scale variation in DNA copy number in chicken breeds

Large scale variation in DNA copy number in chicken breeds.jpg

Detecting genetic variation is a critical step in elucidating the molecular mechanisms underlying phenotypic diversity. Until recently, such detection has mostly focused on single nucleotide polymorphisms (SNPs) because of the ease in screening complete genomes. Another type of variant, copy number variation (CNV), is emerging as a…

Pasteurization of chicken litter with steam and quicklime to reduce Salmonella Typhimurium

Pasteurization of chicken litter with steam and quicklime to reduce Salmonella Typhimurium.jpg

The nursery industry pasteurizes soil with steam and quicklime to reduce plant pathogens. The mechanism of action for quicklime is the resulting exothermic reaction that occurs when the chemical interacts with water and its ability to increase pH levels. These treatments may also reduce pathogens in a commercial poultry house. In this study,…

Effects of litter amendments on broiler growth characteristics and Salmonella colonization in the crop and cecum

Effects of litter amendments on broiler growth characteristics and Salmonella colonization in the crop and cecum.jpg
Salmonella can be prevalent in poultry litter and can be a source of contamination for chicks newly arrived at the poultry house. The objective of this study was to determine the effects of litter amendments on broiler grow-out characteristics (BW and feed conversion), litter moisture, and Salmonella enterica serovar Typhimurium colonization in the…

Distribution of Plant Nutrient Elements and Carbon in Particle Size Fractions of Broiler Litter Ash

Distribution of Plant Nutrient Elements and Carbon in Particle Size Fractions of Broiler Litter Ash.jpg
An estimated 10.8 million tons of broiler litter and 3.0 million tons of turkey litter were produced in the United States in 2009. Poultry litter is a mixture of manure, bedding material (e.g., wood chips, sawdust, or straw), feathers, and spilled feed. Poultry litter contains high levels of Ca, N, P, and K, and is often applied as a fertilizer on…

Broiler litter ammonia emissions near sidewalls, feeders, and waterers

Broiler litter ammonia emissions near sidewalls, feeders, and waterers.jpg
Ammonia (NH3) volatilized from broiler litter diminishes indoor air quality, which can potentially decrease bird productivity. Emissions of NH3 exhausted from broiler houses pose environmental concerns for ecosystem biodiversity, aquatic nutrient enrichment, and particulate formation in the atmosphere. Research was conducted sampling litter (rice…

Atmospheric ammonia is detrimental to the performance of modern commercial broilers

Atmospheric Ammonia Is Detrimental to the Performance of Modern Commercial Broilers.jpg
Atmospheric ammonia inhibits broiler performance. Quantified effects are based on older genetic stock with a BW of 2,000 g at 7 wk. In contrast, modern genetic stock reaches 3,200 g at 7 wk of age. To assess the impact on present day broilers, 2 trials were conducted exposing male broilers to graded levels (0, 25, 50, and 75 ppm) of aerial ammonia…

Application of an electrostatic space charge system for dust, ammonia, and pathogen reduction in a broiler breeder house

Application of an electrostatic space charge system for dust, ammonia, and pathogen reduction in a broiler breeder house.jpg
Airborne dust in poultry housing is known to be one of the primary means by which disease-causing organisms are spread throughout a house. An electrostatic space charge system (ESCS) was used to reduce airborne dust in a small-scale broiler breeder house. The system used ceiling fans to distribute negatively charged air throughout the room and to…

Ammonia Emissions from Twelve U.S. Broiler Chicken Houses

Ammonia Emissions from Twelve U.S. Broiler Chicken Houses.jpg
Twelve commercial broiler houses in the U.S. were each monitored for at least thirteen 48 h periods over the course of one year to obtain ammonia emission data. Paired repetition of houses on four farms represents current construction with variety in litter management (built-up or new litter each flock) and climate conditions (cold or mixed-humid).…

Microbial and antibiotic resistant constituents associated with biological aerosols and poultry litter within a commercial poultry house

Microbial and antibiotic resistant constituents associated with biological aerosols and poultry litter within a commercial poultry house.jpg
Poultry are known to harbor antibiotic resistant and pathogenic bacteria, and as such poultry litter and poultry house air can be contaminated with these bacteria. However, the presence of antibiotic resistant bacteria in biological aerosols and litter is largely not understood. The purpose of this study was to determine the amount of aerosolized…