Effects of Aflatoxin on Young Turkeys and Broiler Chickens

Abstract

The effect of crude aflatoxin (AF) on the growth, performance, and immune response of turkeys and broilers was studied. Crude AF, produced from a natural outbreak of Aspergillus flavus on corn, was ground and mixed in rations to contain either 0, 100, 200, 400, or 800 ppb of aflatoxin B1 (AFB1). Turkeys (Experiment 1) and broilers (Experiment 2) were used in identical experimental designs. In each, 200, 14-day-old birds were divided equally by sex into five groups of 40 and were fed one of five AF diets for 35 days. In Experiment 1, crude AF greater than or equal to 400 ppb was highly toxic to turkeys. These levels produced signs and lesions of aflatoxicosis as well as a significant decrease in weight gain and feed conversion during 5 weeks. In addition, microscopic lesions, indicative of aflatoxicosis, were evident as low as 100 ppb, and significant decreases in cell-mediated immunity were noted in the 200 ppb group birds. Experiment 2 indicated that chickens were less susceptible to crude AF than turkeys. Neither morbidity nor mortality occurred in broilers. Gross lesions consistent with AF toxicity were evident in birds given 800 ppb and microscopic lesions were observed in birds given 100 ppb. Feed conversion was significantly increased in the 800 ppb broilers only. Cell-mediated immunity, measured by a delayed hypersensitive skin test, was significantly decreased in broilers receiving AF at 200 ppb or greater. Neither humoral immunity nor the development of the acquired immunity to Newcastle disease or fowl cholera vaccination were decreased in turkeys or broilers given AF.

Performance and Cell-Mediated and Humoral Immune Responses in Broilers Fed an Aflatoxin Supplemented Diet

“…However, supplementing 500 or 750 ppb AFB, resulted in a poorer (P<0.05) feed conversion compared to that observed for the controls (Table 2). These data are in agreement with those published by Giambrone et al (1985b), who reported poorer feed conversion in birds fed 400 ppb AFB, in a corn-based diet. No data on feed consumption were reported in that study.…”

“…However, those fed 500 ppb AFB, and 750 ppb AFB, were significantly lighter (P<0.05) than the controls (Table 2). These data agree with other reports (Giambrone et al, 1985a and1985b), in which a significant reduction in body weight in five-week-old broilers was observed only when fed a diet supplemented with at least 500 ppb AFB,.…”

“…This decrease in the inflammatory reaction suggests that T cell function is being compromised. In a similar study, a significant decrease in CBH response was first observed at the lowest concentration of 200 ppb AFB, (Giambrone et al, 1985b) which corresponded closely t o the decrease observed at 250 ppb in the current study.…”

Comparative Evaluation of Different Techniques for Aflatoxin Detoxification in Poultry Feed and Its Effect on Broiler Performance

“…Similarly, Verma et al, (2004) reported a significant decrease in the relative weight of the bursa of Fabricius when birds were exposed to diets having 2000 ppb AF. Similar reduction in BBR and moderate histopathological changes have been reported in broilers (Giambrone et al, 1985;Marquez and Hernandez, 1995), laying hens (Dafalla et al, 1987), ducks (Sell et al, 1998;Khajarern and Khajarern, 1999) and wild turkeys (Quist et al, 2000) when birds were fed diets having various levels of AF (100 to 500 ppb). In addition, vacuolation of liver cells and cellular depletion in the follicle medulla of the bursa Fabricii has been reported to be produced as an indication of aflatoxicosis by feeding lower levels of AF (100 ppb) over a long-term period of 42 days (Espada et al, 1992).…”

Perfil leucocitário de frangos de corte tratados com ocratoxina A

“…Afetam taxa de crescimento, conversão alimentar e eficiência reprodutiva do plantel, com repercussões sobre a relação custo-benefício das indústrias avícolas (Jelinek et al, 1989;Santin et al, 2001). As intoxicações, em sua maioria, são decorrentes da ingestão acidental de pequenas quantidades de xenobióticos fúngicos, resultando em declínio mensurável do desempenho produtivo e em alterações clínicas que, embora inespecíficas, estão relacionadas com a ocorrência de hemorragias subcutâneas e imunossupressão (Giambrone et al, 1985).A ocratoxina A (OTA) é um pentapeptídeo derivado da isocumarina e da L-b-fenilalanina, produzido sob a forma de metabólito secundário por várias espécies de Aspergillus e Penicillium (Pitt, 2000a;Pitt, 2000b). Sua denominação foi definida por ter sido isolada pela primeira vez, como produto xenobiótico, de cultivares de Aspergillus ochraceus (StuderKohr et al, 1995).…”