Acute and prolonged effects of ammonia on hematological variables, stress responses, performance, and behavior of nursery pigs

• Published in: Journal of swine health and production Vol. 15; no. 3; pp. 137 - 145
• Main Authors: Borell, E. von, Ozpinar, A, Eslinger, K.M, Schnitz, A.L, Zhao, Y, Mitloehner, F.M
• Format: Journal Article
• Language: English
• Published: 01.05.2007
• Subjects: ammonia; animal behavior; animal stress; hematologic tests; swine
• ISSN: 1537-209X; 2640-3994
• DOI: 10.54846/jshap/500

Objectives: To determine acute and prolonged effects of 35 and 50 ppm concentrations of atmospheric ammonia (NH3) on welfare of weaned pigs. Materials and methods: Two experiments were conducted using gas exposure chambers to investigate prolonged effects (Experiment One; 19 days) and acute effects (Experiment Two; 96 hours) of NH3. Each experiment included two studies: exposure to NH3 at 0 and 35 ppm and at 0 and 50 ppm. In Experiment One, body weight, hematological and metabolic variables, and serum cortisol and haptoglobin were assessed, and behaviors were video-taped. In Experiment Two, serum cortisol and haptoglobin and plasma tumor necrosis factor-α were measured. Results: Absolute counts of white blood cells, lymphocytes, and monocytes were greater in pigs exposed to 35 ppm NH3 than in controls (P < .05). Serum haptoglobin was higher in pigs exposed to 50 ppm NH3 for 7 and 19 days than in controls (P < .05). Serum cortisol concentrations were greater in pigs exposed to 35 or 50 ppm NH3 for 19 days than in controls (P < .05). Less feeding behavior was observed in pigs exposed to 50 ppm NH3 than in controls (P < .05). In acute studies, serum cortisol concentrations were greater in pigs exposed to NH3 than in controls (P < .05). Implications: Under the conditions of these studies, prolonged exposure to NH3 is associated with increases in absolute monocyte, lymphocyte, and neutrophil counts and in serum cortisol and haptoglobin concentrations, but has no effect on pig growth performance.