Effect of coumaphos on cholinesterase activity, hematology, and biochemical blood parameters of bovines in tropical regions of Mexico.
To assess the effect of coumaphos [O-(3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7-yl) O,O-diethyl phosphorothioate] exposure on physiological responses during bovine production, acetylcolinesterase (AChE) and butyrylcholinesterase (BuChE) activities were measured in whole blood, erythrocytes, and plasma of healthy male steers (Bos Taurus x Bos indicus) sprayed with coumaphos at a non-lethal dose of 1 mg kg(- 1) body weight per day once every 14 (in vivo group) or 21 days (southern and central groups). Coumaphos topically administered at 1 mg/kg body weight per day to cattle under normal management practices in tropical areas produced a significant inhibition in erythrocyte (RBC) AChE and BuAChE activities when compared to baseline levels. RBC-AChE activity for the in vivo group decreased 71.3% (P < 0.05) and BuChE activity 59.1% (P < 0.05); RBC-AChE activity decreased 55.1% (P < 0.05) (southern group) and 43.4% (P < 0.05) (central group). Compared to the control specimens, steers from in vivo, southern, and central groups after 150 days of exposure had lower (P < 0.05) leukocyte count, absolute lymphocyte, erythrocyte, and platelet counts. Decreases in RBC-AChE activities correlated with decreased lymphocyte (r = 1.000, p = 0.01), erythrocyte (r = 1.000, p = 0.003), and platelet counts (r = 0.841, p = 0.036). Significantly increased BUN levels (P < 0.05) correlated with the decrease in RBC-AChE activities (r = - 0.997, p = 0.047) and with the decrease in absolute red blood cell (r = - 0.883, p = 0.020) and lymphocyte (r = - 0.825, p = 0.043) counts; increased (P < 0.05) total plasma protein levels correlated with the decrease in RBC-AChE activities (r = -0.998, p = 0.043), absolute red blood cell (r = - 0.998, p = 0.040), lymphocyte (r = - 0.893, p = 0.017), and platelet (r = -0.855, p = 0.030) counts. The physiological responses correlated with the erythrocyte acetylcholinesterase inhibition could be considered as early indicators or warning responses of bovine exposures to organophosphorus pesticides (OPs).
Pardío
Violeta T
VT
Laboratorio de Toxicología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Veracruzana, Veracruz, México. vpardio@yahoo.com.mx
Ibarra
Nelly De J
Nde J
Waliszewski
Krzysztof N
KN
López
Karla M
KM
D000110:Acetylcholinesterase / Q000097:blood / Q000378:metabolism; D000287:Administration, Topical; D000818:Animals; D001772:Blood Cell Count / Q000662:veterinary*; D001774:Blood Chemical Analysis / Q000662:veterinary; D001806:Blood Urea Nitrogen; D002091:Butyrylcholinesterase / Q000097:blood / Q000378:metabolism; D002417:Cattle / Q000097:blood / Q000502:physiology*; D002800:Cholinesterase Inhibitors / Q000494:pharmacology*; D002802:Cholinesterases / Q000097:blood / Q000378:metabolism*; D003372:Coumaphos / Q000494:pharmacology*; D004781:Environmental Exposure; D004912:Erythrocytes / Q000201:enzymology; D008297:Male; D008800:Mexico; D011897:Random Allocation
D002800:Cholinesterase Inhibitors; D000110:Acetylcholinesterase; D002091:Butyrylcholinesterase; D002802:Cholinesterases; D003372:Coumaphos