RESUMEN
N-acetylcysteine (NAC) has been used safely in humans and in other mammals as an antidote against several toxic and carcinogenic agents, including aflatoxin B1 (AFB1). The aim of this study was to evaluate the capability of dietary supplementation with NAC to ameliorate the effects of subacute intoxication with AFB1 in broiler chickens. One hundred twenty male Hubbard 1-d-old chickens were allocated into one of four dietary treatments: 1) control group without treatment, 2) purified AFB1 added to diet (3 mg/kg of feed) for 21 d, 3) NAC (800 mg/kg BW, daily), or 4) AFB1 plus NAC at the same doses as Groups 2 and 3. Broilers treated with AFB1 plus NAC were shown to be partially protected against deleterious effects on BW (57.8%), daily weight gain (49.1%), feed conversion index (21.4%), plasma and hepatic total protein concentration (45.2, 66.7%), plasma alanine aminotransferase (67.4%), hepatic glutathione-S-transferase (18.8%), and reduced glutathione liver concentration (75.0%). In addition, they showed less intense liver fading, friable texture, and microvesicular steatosis. In the kidney, thickening of glomerular basement membrane was also less severe in NAC+AFB1-treated chickens than in AFB1-treated chickens. Our results suggest that NAC provided protection against negative effects on performance, liver and renal damage, and biochemical alterations induced by AFB1 in broiler chickens. Effects of NAC alone on chick performance were also evaluated. Addition of NAC to diet (800 mg/kg BW) did not negatively affect feed consumption, conversion index, or serum chemistry and did not induce structural changes in the liver or kidney.
Asunto(s)
Acetilcisteína/farmacología , Aflatoxina B1/antagonistas & inhibidores , Pollos , Depuradores de Radicales Libres/farmacología , Enfermedades de las Aves de Corral/prevención & control , Aflatoxina B1/toxicidad , Alanina Transaminasa/sangre , Alanina Transaminasa/efectos de los fármacos , Alimentación Animal , Animales , Aspartato Aminotransferasas/sangre , Aspartato Aminotransferasas/efectos de los fármacos , Proteínas Sanguíneas/efectos de los fármacos , Proteínas Sanguíneas/metabolismo , Peso Corporal/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas , Glutatión/efectos de los fármacos , Glutatión/metabolismo , Glutatión Transferasa/efectos de los fármacos , Glutatión Transferasa/metabolismo , Riñón/efectos de los fármacos , Riñón/patología , Enfermedades Renales/inducido químicamente , Enfermedades Renales/veterinaria , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Hepatopatías/veterinaria , Masculino , Enfermedades de las Aves de Corral/inducido químicamente , Distribución Aleatoria , Resultado del TratamientoRESUMEN
Aflatoxin B(1) (AFB(1)) negatively affects chicken (Gallus domesticus) growth. This effect is more severe during development. We studied the influence of age on the toxic effects of AFB(1) on plasma, renal and hepatic enzymes, under two protocols, in adult and in developing Arbor-Acres chickens. Protocol A: 100 male 4-week-old chickens (640 g), received AFB(1), 0.5, 1.0, or 2.0 microg/g of feed (daily p.o.), a fourth group received an aflatoxin-free diet. Five birds/group were slaughtered at 7, 14, 21 and 28 days of treatment. Body, hepatic and renal weights, succinate-dehydrogenase (SDH) and glutamate-dehydrogenase (GluDH) in plasma and liver were measured. Hepatic SDH and GluDH decreased (P<0.05). Protocol B: two groups of 24 male 1-week-old chickens (106 g) received either aflatoxin-free feed (n=24) or AFB(1) feed (2.0 microg/g). At days 7, 14, 21 and 28, the same parameters of Protocol A were measured. AFB(1) markedly reduced body weight gain (20-30%), plasma proteins, albumin, renal and hepatic protein content (P<0.05) and increased absolute and relative weights of the kidney (P<0.05). SDH and GluDH were reduced (P<0.05), while total renal gamma-glutamyltranspeptidase (GGT) increased (P<0.05). Results suggest that serum proteins, SDH and GluDH are sensitive early indicators of this toxicity that was more severe in developing chickens. Decrease in serum albumin might be used as an early and suitable indicator of the deleterious effect of this mycotoxin in developing chickens.