Publications by authors named "Peter Christopherson"

Understanding SARS-CoV-2 epidemiology in companion animals is critical for evaluating their role in viral transmission and their potential as sentinels for human infections. This large-scale serosurvey analyzed serum samples from 706 cats and 2,396 dogs collected across the USA in 2023 using a surrogate virus neutralization test (sVNT) to detect SARS-CoV-2 antibodies. Overall, 5.

View Article and Find Full Text PDF
Article Synopsis
  • Immune thrombocytopenia (ITP) is a prevalent acquired disorder affecting the blood clotting process primarily in dogs and less frequently in cats, leading to significant health risks in both species.
  • ITP can be classified into primary (autoimmune) and secondary (triggered by other diseases), but there is a lack of systematic evaluation regarding which underlying conditions trigger secondary ITP.
  • A comprehensive study developed guidelines through a structured review of literature, expert input, and consensus-building processes to create diagnostic algorithms and screening recommendations for ITP in dogs and cats.
View Article and Find Full Text PDF

Background: Acidemia in sick or injured horses is often due to lactic acid accumulation. Alterations in platelet function and hemostasis are among numerous deleterious effects caused by decreased physiologic pH.

Objectives: We aimed to evaluate the effect of hyperlactatemia and resultant acidemia on platelet aggregation in equine whole blood using impedance aggregometry.

View Article and Find Full Text PDF

A 4-year-old American Quarter Horse gelding was evaluated for acute non-weight-bearing lameness of the right thoracic limb with swelling in the right shoulder region. Physical examination revealed radial nerve paralysis of unknown etiology. The primary differential diagnosis was musculoskeletal trauma.

View Article and Find Full Text PDF

A 10-year-old castrated male Labrador retriever dog was presented for evaluation of a right elbow mass. Mandibular lymphadenopathy was noted on physical examination. Following sudden death after discharge, a necropsy was performed.

View Article and Find Full Text PDF
Article Synopsis
  • GM1 gangliosidosis is a deadly neurodegenerative disease affecting people of all ages, and new gene therapy in animal models shows promise for future human trials.
  • A study developed a set of biomarkers from various body fluids and imaging techniques that reveal significant changes in GM1 patients and treated cats, indicating the therapy's effectiveness.
  • Results showed improved brain function and structure in GM1 cats after gene therapy, supporting the potential for human clinical trials, with the new biomarkers being critical for measuring treatment outcomes.
View Article and Find Full Text PDF

Neutropenia is common to both Hermansky-Pudlak syndrome type 2 and canine cyclic hematopoiesis (CH) which are caused by mutations in the AP3B1 gene. The purpose of this study was to determine if pearl mice were neutropenic. Complete blood counts (CBCs) and bone marrow differential counts, colony forming unit (CFU) assay, bone marrow lineage negative (lin(-)), Sca(+) and c-kit(+) cells (LSK cells), bone marrow elastase, myeloperoxidase, and cathepsin G enzyme activity were compared in C57Bl6 (Bl/6) and pearl mice.

View Article and Find Full Text PDF

An EDTA-anticoagulated blood sample collected from a 1.5-year-old, intact male, English Bulldog was submitted for a CBC. The CBC data and blood smear evaluation revealed borderline high hematocrit (54%, reference interval 37-55%), inappropriate rubricytosis, moderate leukopenia due to both mature neutropenia and lymphopenia, and mild thrombocytopenia.

View Article and Find Full Text PDF

A 9-month-old male Great Dane had progressive generalized nodular dermatopathy for several months. There were > 100 raised, alopecic, firm, painful nodules throughout the skin. Aspirates from several lesions yielded moderate numbers of irregularly round or polygonal to spindle-shaped cells with mild to moderate anisocytosis and few inflammatory cells, and the cytologic interpretation was proliferation of mesenchymal or histiocytic cells.

View Article and Find Full Text PDF

A 17-year-old Peruvian Paso mare was evaluated for bilateral epistaxis that had been present for at least 3 years. The mare had mild anemia, platelet count within the reference interval, unremarkable coagulation times, and a negative Coggins test. On endoscopic examination, structural abnormalities were not observed in the nasal cavities, pharynx, larynx, trachea, or either guttural pouch, but petechiation was noted in the nasal mucosa.

View Article and Find Full Text PDF