Acute Oral Toxicity and Tolerance of Emamectin Benzoate, Profenofos, and a Sulphur-Based Product in Broiler Chickens

Abstract

Introduction: Pesticide residues in feed and water can adversely affect broiler chickens. This preliminary study aimed to determine the maximum tolerated dose of emamectin benzoate (EB), profenofos, and a sulphur-based product, estimate the profenofos LD50, and evaluate the efficacy of dietary charcoal plus L-carnitine in mitigating the resulting toxicity in broiler chickens.
Materials and methods: A total of 240 broiler chickens of both sexes were procured at 10 days of age and divided into one untreated control group and three treatment arms. The EB was given in drinking water at 300, 500, 1800, and 2300 mg/kg of body weight (BW), profenofos was administered by oral gavage in eight independent dose groups (2.55, 5, 7.5, 10, 20, 50, 100, and 600 mg/kg BW) for acute lethality; and the sulphur-based product was administered in feed (300-2300 mg/kg). The untreated control group was sampled on day 15. Chickens received the EB and sulphur-based product on days 17 and 19, respectively, and the blood samples were collected on days 18 and 20 from these two groups. Serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), and creatinine were measured, and mortality and clinical signs were recorded over 7 days. Dietary charcoal plus L-carnitine was then given to surviving broiler chickens in the EB, profenofos, and sulphur-based product groups.
Results: Profenofos induced dose-dependent mortality, with an acute oral LD₅₀ of approximately 4.7 mg/kg BW. In contrast, EB produced no mortality or clinical signs up to 2300 mg/kg. Across all four EB groups (300-2300 mg/kg), ALP levels were elevated compared to the 15-day controls, whereas SGPT, SGOT, and serum creatinine remained largely unchanged. However, because chickens in EB groups were sampled at 18-20 days of age, the observed ALP elevation could not be distinguished from age-related physiological changes. In contrast, the sulphur-based product caused no mortality or clinical signs at any dose tested. Charcoal plus L-carnitine did not prevent feed refusal in profenofos survivors.
Conclusion: The current findings provided an acute oral profenofos LD50 of approximately 4.7 mg/kg BW in broiler chickens and tolerance observations for EB and a sulphur-based product up to 2300 mg/kg BW.