Liposarcoma in a Backyard Silkie and Retrospective Summary of Neoplasms Diagnosed in Backyard Chickens Submitted to the California Animal Health and Food Safety Laboratory System, 2008-2017

Intestinal-peritoneal Coelioscopy for the Diagnosis of a Mesothelioma in a Pet Chicken

An adult female chicken, from a small backyard flock, was presented to the Ontario Veterinary College Avian and Exotics Service for evaluation of dyspnea and recurrent ascites. An antemortem diagnostic evaluation included a coelomocentesis, coelomic ultrasound, and a coelioscopy procedure. A sample of the fluid collected during the coelomocentesis was submitted for analysis and was determined to be a nonspecific modified proteinaceous transudate. The coelomic ultrasound examination identified numerous coalescing fluid-filled and solid nodules throughout the coelom. However, no site of origin of the nodules could be identified. A coelioscopy of the intestinal-peritoneal cavity was performed by a ventral midline approach, and biopsies collected during the procedure were submitted for histologic examination. The pathologic diagnosis of the biopsy samples was a disseminated neoplasia, presumptively coelomic adenocarcinoma. The chicken received palliative treatment which included periodic coelomocentesis, meloxicam, antibiotics, and deslorelin following the diagnosis of a disseminated neoplasia. Three months following initial presentation the patient was euthanatized. A postmortem examination with histopathology confirmed the tissue biopsy results of coelomic neoplasia. Further immunohistochemistry supported mesothelioma as the definitive diagnosis. This case documents the usefulness of intestinal-peritoneal coelioscopy in identifying neoplasia as the cause of ascites in a pet chicken as well as describing the clinical features and progression of a mesothelioma in this species.

A two-year prospective study of small poultry flocks in Ontario, Canada, part 2: causes of morbidity and mortality

Non-commercial poultry flocks (referred to as "small flocks") have become increasingly popular in Canada. Despite this popularity, little is known about the main causes of morbidity and mortality (health status) in these flocks. We assessed the baseline prevalence of infectious and non-infectious diseases among Ontario's small poultry flocks by conducting a prospective surveillance study over a 2-y period. With the owner's consent, for each bird ( n = 245) submitted to the Animal Health Laboratory, we performed a postmortem examination, including ancillary tests to reach a diagnosis. Infectious diseases were the most common primary cause of clinical signs or death (62%), with multifactorial respiratory diseases (21%) and Marek's disease (11%) being most frequent. Multifactorial respiratory diseases were commonly caused by coinfection with bacteria (e.g., Mycoplasma gallisepticum and M. synoviae, Escherichia coli, Avibacterium spp.) and viruses, such as infectious bronchitis and infectious laryngotracheitis viruses. No federally reportable diseases were diagnosed. The health status of small flocks in Ontario has not been reported previously, to our knowledge, and the data presented herein will produce helpful baseline information for the development of technology transfer material directed to owners and veterinarians, which will ultimately aid in the control of diseases among these flocks.