Effects of Thirty-Day Exposure of Quails (Coturnix Coturnix) to Formalin Vapor on Biochemical, Immunological, and Histological Features of Liver and Kidney

Formalin is a highly toxic chemical that causes tissue damage. Formalin is metabolized by the liver and erythrocytes and excreted via the urinary and digestive tracts. This passage may propose toxicity in these systems. Thus, the current study was conducted to examine serological, and histological changes in the kidney and liver of formalin-vapor-exposed quails (FVEQs) (Coturnix coturnix) to promote awareness of formalin toxicity in the farms of Japanese quails. The study included the recruitment of 16 adult quails divided into four equal groups; control group (no formalin exposure), FVEQ1 group (exposed to formalin for 10 days), FVEQ2 (exposed to formalin for 20 days), and FVEQ3 (exposed to formalin for 30 days). All FVEQs were exposed to formalin vapor twice daily (morning and evening, 2hrs/each). Each group was reared in a separate airtight chamber during the experiment time (10, 20, or 30 days). blood samples for renal and liver, IgG levels, and histopathological features were examined.  The findings showed significant (p<0.05) increases in the levels of blood creatinine, urea, and uric acid in the FVEQ groups. Liver enzymes, ALP, ALT, and AST revealed significant (p<0.05) increases in the FVEQ groups. FVEQ1 group recorded significantly (p<0.05) the highest IgG level after 10 days of formalin exposure, which significantly (p<0.05) decreased after 10 days without formalin exposure, and immunity was slightly restored. The histopathological characteristics of the kidney were increases in the thickness of renal corpuscles, glomeruli, and the Henle loop of the medullary cone. For the liver, the findings showed increases in the parenchymal aggregation of lymphoid cells. There were amyloid depositions in hepatocyte spaces, which were squeezed and atrophied, creating intercellular gaps and reducing cell compactness. The inhalation of formalin vapor may damage the kidney and liver tissues and eventually their functioning in formalin-exposed quails.