Are peripheral Mott cells an indication of stress or inefficient immunity?

Area of Science:

• Avian pathology
• Comparative hematology
• Immunology

Background:

• Mott cells are atypical plasmacytes characterized by distinctive cytoplasmic vacuoles.
• Previous descriptions of avian Mott cells in scientific literature are scarce.
• These cells have been observed in various housing systems, including conventional, aviaries, and enriched environments.

Purpose of the Study:

• To describe the occurrence and characteristics of Mott cells in commercial poultry.
• To investigate the association of Mott cells with hematological parameters and disease states.
• To highlight the significance of Mott cells as indicators of avian health and welfare.

Main Methods:

• Peripheral blood samples were collected from commercial hens at various ages (18, 32, 48, 56, and 77 weeks).
• Hematological analysis was performed, including total white blood cell counts and heterophil/lymphocyte ratios.
• Morphological examination of blood smears was conducted to identify and quantify Mott cells.
• Presence of bacteremia and fungemia was assessed in affected birds.

Main Results:

• Mott cells were detected in 7.7% (77/1,000) of commercial hens.
• The earliest detection of Mott cells was at 18 weeks of age.
• Mott cells were associated with both high (leukocytosis) and low white blood cell counts.
• Phagocytosis of bacteria by Mott cells was observed, and many positive hens had polymicrobial bacteremia or fungemia.
• Mott cells were also identified in other poultry species, including toms and ducklings.

Conclusions:

• Mott cells are significant cytological indicators of hemogram abnormalities and potential stress in poultry.
• Their presence suggests underlying inflammatory or infectious conditions, such as bacteremia and fungemia.
• Mott cells contribute valuable information to avian hematology, immunology, and cytology.
• The identification of Mott cells has direct implications for assessing animal welfare in commercial poultry operations.