Longitudinal Monitoring of Successive Commercial Layer Flocks for Salmonella enterica Serovar Enteritidis.

The Pennsylvania Egg Quality Assurance Program (EQAP) provided the framework for Salmonella Enteritidis (SE) control programs, including the Food and Drug Administration (FDA) mandated Final Egg Rule, for commercial layer facilities throughout the United States. Although flocks with ≥3000 birds must comply with the FDA Final Egg Rule, smaller flocks are exempted from the rule. As a result, eggs produced by small layer flocks may pose a greater public health risk than those from larger flocks.

Incidence, Severity, and Welfare Implications of Lesions Observed Postmortem in Laying Hens from Commercial Noncage Farms in California and Iowa.

The egg industry is moving away from the use of conventional cages to enriched cage and noncage laying hen housing systems because of animal welfare concerns. In this study, the prevalence and severity of lesions in noncage laying hens from commercial farms in two of the largest egg-producing states, California and Iowa, were evaluated by postmortem examination. Hens that died or were culled were collected during early, mid, and late stages of the laying cycle from 16 houses on three farms.

Subclinical avian hepatitis E virus infection in layer flocks in the United States.

The objective of this study was to determine patterns of avian HEV infection in naturally infected chicken farms. A total of 310 serum samples and 62 pooled fecal samples were collected from 62 chicken flocks on seven commercial in-line egg farms in the Midwestern United States and tested for avian HEV circulation. Serum samples were tested for the presence of anti-avian HEV IgY antibodies by a fluorescent microbead immunoassay (FMIA) which was developed for this study.

Comparison of the pathogenicity of the USDA challenge virus strain to a field strain of infectious laryngotracheitis virus.

Infectious laryngotracheitis virus (ILTV) causes respiratory disease in chickens. This alphaherpesvirus infects laryngeal tracheal epithelial cells and causes outbreaks culminating in decreases in egg production, respiratory distress in chickens and mortality. There are several different vaccines to combat symptoms of the virus, including chicken embryo origin, tissue culture origin and recombinant vaccines.

Identification and characterization of avian hepatitis E virus in 2013 outbreaks of hepatitis-splenomegaly syndrome in two US layer operations.

Two commercial Midwestern egg-type chicken flocks experienced significant increases in mortality rates in April 2013 with clinical signs appearing in 17-week-old pullets on Farm A and in 46-week-old hens on Farm B. Average weekly mortality was 0.44% over a 4-week period on Farm A and 0.

Detection of Salmonella enteritidis in pooled poultry environmental samples using a serotype-specific real-time-polymerase chain reaction assay.

While real-time-polymerase chain reaction (RT PCR) has been used as a rapid test for detection of Salmonella Enteritidis in recent years, little research has been done to assess the feasibility of pooling poultry environmental samples with a Salmonella Enteritidis-specific RT PCR assay. Therefore the objective of this study was to compare RT PCR Salmonella Enteritidis detection in individual and pooled (in groups of two, three, and four) poultry environmental drag swab samples to traditional cultural methods. The drag swabs were collected from poultry facilities previously confirmed positive for Salmonella Enteritidis and were cultured according to National Poultry Improvement Plan guidelines.

Genome analysis and phylogenetic relatedness of Gallibacterium anatis strains from poultry.

Peritonitis is the major disease problem of laying hens in commercial table egg and parent stock operations. Despite its importance, the etiology and pathogenesis of this disease have not been completely clarified. Although avian pathogenic Escherichia coli (APEC) isolates have been incriminated as the causative agent of laying hen peritonitis, Gallibacterium anatis are frequently isolated from peritonitis lesions.

Identification and characterization of H2N3 avian influenza virus from backyard poultry and comparison with novel H2N3 swine influenza virus.

In early 2007, H2N3 influenza virus was isolated from a duck and a chicken in two separate poultry flocks in Ohio. Since the same subtype influenza virus with hemagglutinin (H) and neuraminidase (N) genes of avian lineage was also identified in a swine herd in Missouri in 2006, the objective of this study was to characterize and compare the genetic, antigenic, and biologic properties of the avian and swine isolates. Avian isolates were low pathogenic by in vivo chicken pathogenicity testing.

Moving-average trigger for early detection of rapidly increasing mortality in caged table-egg layers.

Rapidly increasing and unexplained mortality in commercial poultry flocks may signal the presence of a highly transmissible and reportable disease. Activation of an infectious-disease surveillance system occurs when a key production parameter, i.e.

Complete genome sequence of Gallibacterium anatis strain UMN179, isolated from a laying hen with peritonitis.

Gallibacterium anatis is a member of the normal flora of avian hosts and an important causative agent of peritonitis and salpingitis in laying hens. Here we report the availability of the first completed G. anatis genome sequence of strain UMN179, isolated from an Iowa laying hen with peritonitis.

Field estimation of the flock-level diagnostic specificity of an enzyme-linked immunosorbent assay for Avian metapneumovirus antibodies in turkeys.

Routine serologic testing for Avian metapneumovirus (AMPV) infection of turkey flocks at slaughter is currently being used to monitor changes in the occurrence of AMPV infection in endemic areas and can also be used to detect the emergence of infection in currently unaffected areas. Because of the costs associated with false-positive results, particularly in areas that are free of AMPV infection, there is a need to obtain improved estimates of flock-level specificity (SP). The objective of this study was to estimate flock-level SP of a program to monitor AMPV infection in turkey flocks at processing using a standard enzyme-linked immunosorbent assay (ELISA).

Prevalence of Campylobacter jejuni and Campylobacter coli in market-weight turkeys on-farm and at slaughter.

To monitor the effects of feed withdrawal on the prevalence of Campylobacter, market-weight turkeys from six farms were examined before and after perimarketing events (feed withdrawal, transport, and holding at the slaughterhouse). Prior to transport, birds (n = 30 per farm) were slaughtered on-farm, and viscera (crops, duodenum, jejunum, ileum, colon, ceca, gallbladder, and spleen) were removed on the premises. Within ca.

The onset of virus shedding and clinical signs in chickens infected with high-pathogenicity and low-pathogenicity avian influenza viruses.

Some avian influenza viruses may be transmissible to mammals by ingestion. Cats and dogs have been infected by H5N1 avian influenza viruses when they ate raw poultry, and two human H5N1 infections were linked to the ingestion of uncooked duck blood. The possibility of zoonotic influenza from exposure to raw poultry products raises concerns about flocks with unrecognized infections.

Characterization of Escherichia coli isolates from peritonitis lesions in commercial laying hens.

Five clinically normal chickens from three farms (farm A, farm B, and farm C), for a total of 15 clinically normal chickens, were examined bacteriologically. In a similar manner, five dead chickens with lesions of peritonitis from each of the same three commercial egg-laying operations were selected for bacterial culturing. Escherichia coli were isolated from the cloaca in 14 of 15 healthy chickens and from all 15 chickens with peritonitis.

Pandemic influenza planning: shouldn't swine and poultry workers be included?

Recent research has demonstrated that swine and poultry professionals, especially those who work in large confinement facilities, are at markedly increased risk of zoonotic influenza virus infections. In serving as a bridging population for influenza virus spread between animals and man, these workers may introduce zoonotic influenza virus into their homes and communities as well as expose domestic swine and poultry to human influenza viruses. Prolonged and intense occupational exposures of humans working in swine or poultry confinement buildings could facilitate the generation of novel influenza viruses, as well as accelerate human influenza epidemics.

Prevalence of Arcobacter species in market-weight commercial turkeys.

The prevalence of Arcobacter in live market weight turkeys was determined for six Midwestern commercial flocks at three intervals. Samples (n = 987) were collected from cloaca, feathers, ceca, crop, drinkers and environmental samples on farms and from carcasses at slaughter. Initially, EMJH-P80 and CVA isolated Arcobacter from 7.

Detection of antibodies in serum and egg yolk following infection of chickens with an H6N2 avian influenza virus.

Active serologic surveillance programs to detect avian influenza viruses (AIVs) in table egg-laying chickens have been initiated by several states as a response to the economic threat posed by these viruses. Most outbreaks of avian influenza in domestic poultry are caused by mildly pathogenic AIVs. In the study reported here, infection by an H6N2 AIV was used as a model of mildly pathogenic AIV infections in egg-type chickens.

Effect of preslaughter events on the prevalence of Salmonella in market-weight turkeys.

The goal of this study was to determine if preslaughter events, such as transport to and holding at the slaughterhouse, affect Salmonella prevalence in turkeys. Floors of transport crates were swabbed after loading and prior to transport at the farm (time 1, n = 100 swabs per trial) and after transport to and holding at the abattoir (time 2, n = 100 swabs per trial). In addition, environmental samples were taken at each of the six premises (n = 25 per premises) as well as in the holding shed at the abattoir (n = 25 samples per trial).

Epidemiological investigation, cleanup, and eradication of pullorum disease in adult chickens and ducks in two small-farm flocks.

Pullorum disease causing acute septicemia and mortality in adult brown chickens was diagnosed in a small-farm chicken flock in Iowa. Also, Salmonella Pullorum was isolated from the intestine of one of four rats trapped on this index farm. Tracing movements of spent hens from the index farm resulted in identification of a second infected flock on a contact farm.

Toxicoinfectious botulism in commercial caponized chickens.

During the summer of 2003, two flocks of commercial broiler chickens experienced unusually high death losses following caponizing at 3 wk of age and again between 8 and 14 wk of age. In September, fifteen 11-wk-old live capons were submitted to the Iowa State University Veterinary Diagnostic Laboratory for assistance. In both flocks, the second episode of elevated mortality was associated with incoordination, flaccid paralysis of leg, wing, and neck muscles, a recumbent body posture characterized by neck extension, and diarrhea.

Effect of preslaughter events on prevalence of Campylobacter jejuni and Campylobacter coli in market-weight turkeys.

The effects of events which occur prior to slaughter, such as loading, transport, and holding at an abattoir, on the prevalence of Campylobacter species, including Campylobacter jejuni and Campylobacter coli, were examined. Cloacal swabs from market-weight turkeys in each of five flocks were obtained on a farm prior to loading (time 1; 120 swabs per flock) and after transport and holding at the abattoir (time 2; 120 swabs per flock). A statistically significant increase in the overall prevalence of Campylobacter spp.

Lead contamination of chicken eggs and tissues from a small farm flock.

Twenty mixed-breed adult laying hens from a small farm flock in Iowa were clinically normal but had been exposed to chips of lead-based paint in their environment. These chickens were brought to the Iowa State University Veterinary Diagnostic Laboratory, Ames, Iowa, where the concentration of lead in blood, eggs (yolk, albumen, and shell), and tissues (liver, kidney, muscle, and ovary) from 5 selected chickens was determined over a period of 9 days. Blood lead levels ranged from less than 50 to 760 ppb.