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Avian Dis 2022 Apr 27. Epub 2022 Apr 27.

Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, 4008 VM3B, Davis, CA 95616,

Two 7-wk-old broiler chickens presented with uniformly black livers upon postslaughter examination, while all other organs as well as their carcasses were grossly normal. No clinical signs were reported by the field veterinarian prior to slaughter. Other broiler chickens within the same flock were unaffected. Read More

Avian Dis 2022 Apr 28. Epub 2022 Apr 28.

California Animal Health and Food Safety Laboratory, University of California-Davis, San Bernardino, California, USA, 95616.

A 3-yr-old Ameraucana hen was received for postmortem examination following a 1-day history of lethargy and death. Gross lesions observed during necropsy were limited to pulmonary congestion and a small clump of egg yolk material in the oviductal lumen. On histopathology, there was a necrotizing salpingitis of the infundibular and isthmus mucosa with amphophilic, intranuclear inclusion bodies in superficial epithelial cells. Read More

Avian Dis 2022 Apr 27. Epub 2022 Apr 27.

Avian Disease Division, Animal and Plant Quarantine Agency, Gimcheon-si, Gyeongsangbuk-do 39660, Republic of Korea,

Infectious bronchitis virus (IBV) is a major pathogen in poultry. The genotypes of IBV vary considerably, and their antigenicity may differ. Nationwide surveillance in South Korea was performed to determine the prevalence and distribution of IBV and its genotypes. Read More

Avian Dis 2022 Apr 27. Epub 2022 Apr 27.

Louisiana State University School of Veterinary Medicine, Baton Rouge, LA 70803.

Vitamin D is a hormone that can be ingested or synthesized in the body when skin is exposed to ultraviolet radiation (UV), typically from sunlight. In captivity, birds with no sunlight exposure may develop vitamin D deficiencies that may contribute to hypocalcemic conditions, even when fed a diet supplemented with vitamin D. An initial pilot study with Hispaniolan Amazon parrots () conducted approximately 18 mo prior indicated there were significant differences in the 25-hydroxyvitamin D (vit D) plasma levels between the resident parrots (indoor-only housing) and a new group of historically outdoor-housed parrots (new parrots) 5 days after the arrival of the latter at our institution. Read More

Avian Dis 2022 May 2. Epub 2022 May 2.

Department of Veterinary Population Medicine and Veterinary Diagnostic Laboratory, University of Minnesota, St. Paul, MN 55455.

Newcastle disease virus (NDV) can infect approximately 250 avian species and causes highly contagious Newcastle disease (ND) in domestic poultry, leading to huge economic losses. There are three different pathotypes of NDV, i.e. Read More

Avian Dis 2022 May 2. Epub 2022 May 2.

University of Alaska Museum, University of Alaska Fairbanks, Fairbanks, AK 99775.

Avian influenza (AI) is a zoonotic disease that will likely be involved in future pandemics. Because waterbird movements are difficult to quantify, determining the host-specific risk of Eurasian-origin AI movements into North America is challenging. We estimated relative rates of movements, based on long-term evolutionary averages of gene flow, between Eurasian and North American waterbird populations to obtain bidirectional baseline rates of the intercontinental movements of these AI hosts. Read More

Avian Dis 2022 Apr 5. Epub 2022 Apr 5.

Southeast Poultry Research Laboratory, United States Department of Agriculture-Agricultural Research Service, United States National Poultry Research Center, Athens, GA,

Sanitary disposal of contaminated organic material during recovery from an animal disease outbreak is costly and laborious. Characterizing the thermal stability of avian paramyxovirus type 1 (APMV-1; virulent APMV-1 strains cause Newcastle disease in poultry) will help inform risk assessments on the presence of viable virus on infected premises or in organic waste from infected premises. In some environments and housing types, heat may also be used as a decontamination method. Read More

Avian Dis 2022 Mar 30. Epub 2022 Mar 30.

California Animal Health and Food Safety Laboratory System-Tulare branch, University of California Davis, Tulare, CA 93274.

Necrotic enteritis (NE) is a serious disease of chickens and turkeys that causes significant economic losses to the poultry industry. On the basis of studies in chickens, type G is considered by many to be the cause of NE in poultry. However, studies on isolates from Finnish and Italian turkeys with NE revealed that the vast majority were type A, and very few were type G. Read More

Avian Dis 2022 Mar 14. Epub 2022 Mar 14.

Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607,

In the last decade, monitoring Marek's disease (MD) vaccination by real-time PCR has become a common practice. Evaluating replication of MD vaccines in the feather pulp (FP) at 7 days of age provides information on how well a flock has been vaccinated. Factors such as vaccine dose, combination with other vaccines, age and route of vaccination, and the origin of the vaccine can influence the results and need to be taken into consideration. Read More

Avian Dis 2022 Mar 16. Epub 2022 Mar 16.

Poultry Research and Diagnostic Laboratory, Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University 3137 MS-468, Pearl, MS 39208.

Necrotic enteritis (NE) is an important intestinal disease of commercial poultry associated with poor performance, high mortality, and significant economic loss. In this case report, a novel presentation of NE is described in young broilers. Initially, affected farms presented with a moderate increase in mortality at or before 19 days of age. Read More

Avian Dis 2022 Mar 14. Epub 2022 Mar 14.

Department of Pathobiology, Auburn University College of Veterinary Medicine, Auburn AL 36849,

Resistance to infectious bronchitis (IB) is a polygenic trait, but little is known about how resistance distributes in the host population. In this study, a relatively large number (n = 369) of specific-pathogen-free white leghorn chickens () were challenged with an Arkansas -type virulent IB virus (IBV), and resistance was evaluated 5 days after challenge by viral load (IBV RNA) in the trachea and cecal tonsils, as well as by tracheal histomorphometry (mucosal thickness and lymphocyte infiltration). Contrary to expectations, results showed a non-Gaussian distribution of resistance of the whole population against challenge. Read More

Avian Dis 2022 Feb 25. Epub 2022 Feb 25.

Laboratory of Veterinary Pathology, Co-Department of Veterinary Medicine, Iwate University, Morioka 020-8550, Japan.

Fowl glioma-inducing virus (FGV), a strain of avian leukosis virus (ALV) subgroup A, is the causal agent of fowl glioma characterized by multiple nodular astrocytic growths, gliosis, and lymphocytic encephalitis. Also associated with FGV infection are cases of cerebellar hypoplasia, perineuromas, and nonsuppurative myocarditis. Though fowl glioma has been recognized in several countries, most reports of FGV infection come from Japan. Read More

Avian Dis 2022 Feb 2. Epub 2022 Feb 2.

Department of Poultry Science, University of Georgia, Athens, GA 30602.

Anticoccidial drug resistance in coccidia has been known since the 1960s, and experimental selection for resistance in the laboratory has been done for most available products. However, routine testing for sensitivity in field isolates has only begun in recent years. Poultry producers are faced with greater challenges because of consumer preferences for 'antibiotic-free' products and a lack of new products for disease control. Read More

Avian Dis 2022 Feb 10. Epub 2022 Feb 10.

Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061,

Runting stunting syndrome (RSS) in broiler chickens is characterized by altered intestinal morphology and gene expression and stunted growth. The objective of this study was to conduct a retrospective study of gene expression in stem and differentiated cells in the small intestine of RSS chicks. Two different models of RSS were analyzed: broiler chicks that were experimentally infected and broiler chicks that were naturally infected. Read More

Avian Dis 2022 Jan 20. Epub 2022 Jan 20.

Veterinary Diagnostic Pathology, LLC, Fort Valley, VA 22652.

Infectious bronchitis is a respiratory disease of chickens caused by a gammacoronavirus named infectious bronchitis virus (IBV). In addition to affecting the respiratory tract, IBV may also induce urogenital infections, leading to nephropathogenic disease, false layer syndrome in laying hens, and epididymal lithiasis and epididymitis in males. Here, we report a case of decreased reproductive efficiency due to male infertility in 33- to 38-wk-old broiler breeders. Read More

Avian Dis 2022 Jan 10. Epub 2022 Jan 10.

Animal Science, School of Environmental and Rural Science, University of New England, Armidale, New South Wales 2351, Australia.

Currently, there is no available vaccine against hemorrhagic enteritis virus (HEV) in Australia. Although it is assumed that subclinical HEV infections occur and may be associated with an increase in colibacillosis in Australian commercial turkey flocks, the prevalence of infection with this virus in the country is largely unknown. The aims of this study were to determine the extent of HEV infection in commercial flocks in Australia and to investigate the diversity of Australian HEV strains. Read More

Avian Dis 2022 Feb 17. Epub 2022 Feb 17.

Egg Safety and Quality Research Unit, US National Poultry Research Center, USDA Agricultural Research Service, Athens, GA 30605,

In 2018, a national recall of shell eggs in the United States occurred due to human illness caused by Braenderup. Although previous studies have identified Braenderup in laying hens and the production environment, little is known about the ability of this serovar to infect laying hens and contaminate eggs. The objective of this study was to examine the invasiveness of Braenderup in laying hens as well as its ability to persist in the production environment. Read More

Avian Dis 2022 Feb 11. Epub 2022 Feb 11.

Avian Diseases and Oncology Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, East Lansing, MI 48823.

Marek's disease (MD) vaccine does not provide sterilizing immunity that prevents subsequent MD virus (MDV) replication and shedding in vaccinated birds. It is hypothesized that cell-mediated immunity is critical to control the virus replication in chickens because MDV exists in cell-associated forms in the host. To improve the MD vaccine efficacy, particularly cell-mediated immunity, we constructed recombinant v301B/1-IL-15, an MDV serotype 2 vaccine strain 301B/1 expressing chicken interleukin-15 (IL-15), a cytokine which promotes T-cell proliferation and enhances T-cell responses. Read More

Avian Dis 2022 Jan 10. Epub 2022 Jan 10.

Department of Entomology, Washington State University, Pullman, WA 99164,

Growing demand for poultry meat and eggs labeled as organic, cage free, or pasture raised has increased the number of producers that manage chickens outdoors. In these open environments, there are likely diverse enteric parasites sustained by fecal-oral transmission or passage through intermediate invertebrate hosts (e.g. Read More

Avian Dis 2022 Jan 10. Epub 2022 Jan 10.

USDA-ARS, NEA, Beltsville Agriculture Research Center, Animal Biosciences and Biotechnology Laboratory, Beltsville, MD 20705,

The intestinal disease coccidiosis, caused by parasitic species, severely impacts poultry production, leading to an estimated $14 billion in annual losses worldwide. As the poultry industry moves away from antibiotics as a treatment for diseases, a better understanding of the microbiota is required to develop other solutions such as probiotics, prebiotics, and nutritional supplements. This study aimed to investigate the effects of infection on luminal (cecal contents [CeC]) and mucosal (cecal epithelial scrapings [CeS]) microbial populations in 288 Ross 708 broiler chickens at multiple time points postinfection (PI). Read More

Avian Dis 2022 Jan 14. Epub 2022 Jan 14.

Department of Poultry Science, University of Arkansas Division of Agriculture, Fayetteville, AR 72701,

The objectives of this study were to evaluate whether a preinfection of (EAD) or (ET) could affect the severity of subsequent histomoniasis in turkeys (Experiment 1) and if previous exposure to EAD infection, when a single or multiple inoculations of EAD were administered with sufficient time for complete cecal recovery, would affect the severity of HM incidence and lesions (Experiment 2). In Experiment 1, 200 poults were assigned to 1 of 5 groups, as follows: unchallenged negative control, positive challenge control inoculated with 10 HM, EAD at 500 oocysts/bird and (HM), EAD at 2500 oocysts/bird and HM, or ET at 9 × 10 oocysts/bird and HM. ET and EAD were inoculated on day 15 and HM on day 20. Read More

Avian Dis 2022 Feb 16. Epub 2022 Feb 16.

Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606.

Whole blood biochemistry and blood gas analysis are uncommonly used in poultry, but their use could improve the diagnosis of certain diseases or aid in monitoring flock health. To create preliminary reference intervals for selected blood analytes in broilers using the i-STAT and Vetscan VS2 (VS2) portable analyzers, we tested broilers at 7, 21, and 35 days of age. A total of 134 venous blood samples from healthy chickens of two different flocks were analyzed. Read More

Avian Dis 2022 Jan 5. Epub 2022 Jan 5.

Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853,

Bacillary white diarrhea in chickens was a major disease concern for the poultry industry during the early 1900s. Drs. L. Read More

Avian Dis 2021 Dec 22. Epub 2021 Dec 22.

Biodiversity, Ecology and Genome Laboratory, Faculty of Sciences, Mohammed V University in Rabat, 10106 Rabat, Morocco.

Avian influenza (AI) is a zoonotic disease significant to both public and animal health, caused by influenza virus A, and affects domestic poultry, wild birds, and mammals including humans. Aquatic birds are considered the natural reservoir of this virus. In 2016, Morocco experienced the first occurrence of low pathogenic H9N2 avian influenza virus (AIV) in poultry; however, no cases were reported in wild birds. Read More

Avian Dis 2021 Dec 22. Epub 2021 Dec 22.

Institute of Animal Husbandry and Veterinary Medicine, Fujian Academy of Agricultural Sciences, Fujian Animal Diseases Control Technology Center, Fujian Provincial Key Laboratory for Avian Diseases Control and Prevention, Animal Biosafety Level 3 Laboratory of Fujian, Fuzhou 350013, China.

H5N6 subtype avian influenza virus (AIV) continues to erupt in poultry, and there have also been many incidents of human infection. Its outbreak is devastating to the poultry breeding industry, and it also threatens human public health safety. Forty-five strains of H5N6 subtype AIV isolated from sick ducks in East China were used in this study. Read More

Avian Dis 2021 Dec 22. Epub 2021 Dec 22.

Department of Biological Sciences, California State University, Chico, Chico, CA 95929,

Avian influenza viruses (AIVs) are distributed globally in members of the family Anatidae (waterfowl), and significant disease may occur when these viruses infect commercial poultry or humans. Early detection of AIV through surveillance of wild waterfowl is one measure to prevent future disease outbreaks. Surveillance efforts that are designed to account for host and environmental determinants of susceptibility to infection are likely to be most effective. Read More

Avian Dis 2021 12;65(4):659-662

Zoetis, Bâtiment VIVA, 10, Rue Raymond David, 92240 Malakoff, France,

Colibacillosis is a common bacterial disease in broiler production worldwide. It is emerging as a serious health concern in turkey production. Until recently, the disease was managed through antimicrobial therapy. Read More

Avian Dis 2021 12;65(4):643-648

Huntingdon, Cambridgeshire PE29 1XQ, United Kingdom.

Since its first detection in Europe in the 1940s, infectious bronchitis virus has continued to be one of the major respiratory pathogens affecting the European poultry industry. The development of effective and widely used vaccines for both broilers (live attenuated) and breeders and layers (live attenuated and inactivated) helped improve the health and welfare of poultry but never eliminated the problem. The main reason is the continual emergence of new infectious bronchitis variants (serotypes or genotypes). Read More

Avian Dis 2021 12;65(4):637-642

Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849,

Despite continuous and extensive efforts to control infectious bronchitis (IB) throughout the century, the disease continues to be one of the most economically relevant diseases affecting the poultry production worldwide. Since the early 1990s, numerous scientists have explicitly warned about the role of attenuated vaccines on IB virus (IBV) evolution and the detrimental consequences of their use to the poultry industry. Herein, we review evidence indicating that the use of live vaccines increases genetic/phenotypic diversity of IBV, enhances their fitness in the environment, and ultimately aggravates and perpetuates the problem for the poultry industry. Read More

Avian Dis 2021 12;65(4):631-636

Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, Athens, GA 30602.

Infectious bronchitis virus (IBV) is a highly infectious and transmissible gammacoronavirus that is nearly impossible to control through biosecurity. Coronaviruses are RNA viruses with an enormous capacity for rapid replication and high rates of mutation, leading to a tremendous amount of genetic diversity. Viral evolution occurs when selection working on genetic diversity leads to new mutations being fixed in the population over time. Read More