Aflatoxins (AF) and fumonisins (FU) are a major problem faced by poultry farmers, leading to huge economic losses. This experiment was conducted to determine the effects of AF (1 mg/kg of feed) and FU (25 mg/kg of feed), singly or in combination, on the lipid metabolism in commercial layers and investigate the efficacy of a commercial binder (2 kg/t of feed) on reducing the toxic effects of these mycotoxins. A total of 168 Hisex Brown layer hens, 37 wk of age, were randomized into a 3 × 2 + 1 factorial arrangement (3 diets with no binder containing AF, FU, and AF+FU; 3 diets with binder containing AF, FU, and AF+FU; and a control diet with no mycotoxins and binders), totaling 7 treatments. The hens contaminated with AF showed the characteristic effects of aflatoxicosis, such as a yellow liver, resulting from the accumulation of liver fat, lower values of plasma very low-density lipoprotein and triglycerides, and higher relative weight of the kidneys and liver. Hepatotoxic and nephrotoxic effects of FU were not observed in this study. On the other hand, the FU caused a reduction in small intestine length and an increase in abdominal fat deposition. The glucan-based binder prevented some of the deleterious effects of these mycotoxins, particularly the effects of AF on hepatic lipid metabolism, kidney relative weight, and FU in the small intestine.

The effects of aflatoxin and fumonisin and their combination on egg production and quality, as well as the efficacy of a mycotoxin adsorbent in reducing or eliminating these effects in commercial layers. A number of 168 layers with initial age of 37 weeks were submitted to an experimental period of 56 days. A completely randomized experimental design in a 3x2+1 factorial arrangement was applied (3 treatments with mycotoxins: aflatoxin (AF), fumonisin (FU), or aflatoxin + fumonisin (AF+FU); 2 treatments with or without adsorbent; and a control group that was fed no mycotoxins, nor adsorbent), totaling 7 treatments with 6 replicated of 4 birds/cage. The dietary inclusion levels were 1ppm AF, 25ppm FU, and 2 kg adsorbent/ton feed. Birds fed AF presented the lowest percentage of lay (p=0.0594). Egg mass was the lowest (p<0.05) in the AF+FU treatment (49.49g). The treatment with AF resulted in higher eggshell thickness and strength (p<0.05) than the FU treatment and the control group. The inclusion of the adsorbent in the AF contaminated feed reduced eggshell strength, which returned to levels similar to those of the control group. The observed changes indicate that aflatoxin is toxic at a concentration of 1ppm, and that the effects of fumonisin were less evident as a function of the low dose applied. The inclusion of the glucan (2kg/ton) effectively reverted some of the toxic effects of aflatoxin and, at lower extension, those of fumonisin, when these mycotoxins were invidually added to commercial layer feeds.

II RESUMO O efeito da temperatura e o efeito do enriquecimento do piso de gaiola sobre o bem-estar de coelhos em crescimento foram avaliados. Quarenta e oito coelhos do grupo genético Botucatu, desmamados aos 35 dias de idade

This study evaluated the effects of chromium yeast (Cr yeast) and two apparent metabolizable energy (AME) levels on productive performance, egg quality, and lipid and carbohydrate metabolism in laying hens. A total of 192 Bovans White laying hens at 47 weeks of age were randomly assigned to eight dietary treatments (six replicates each) in a 4 × 2 factorial arrangement: four levels of supplemental Cr (0, 0.2, 0.4, and 0.8 ppm as Cr yeast) and two AME levels (2,780 and 2,900 kcal AME kg −1 ). No significant effect of Cr yeast supplementation on feed intake, egg weight, egg production, intact eggs, egg mass, feed conversion ratio, or egg quality was observed. Egg quality parameters and Cr content in the yolk were not affected by dietary treatments. Plasma glucose and lipid levels were not influenced by either Cr yeast or AME levels used in this study. However, Cr yeast supplementation improved yolk percentage and hepatic glycogen content. The inclusion of Cr yeast at 0.2 and 0.4 ppm induced the highest hepatic glycogen content with the energy levels 2,900 and 2,780 kcal AME kg −1 , respectively. Laying hens fed 2,900 kcal AME kg −1 showed the highest abdominal fat. The results observed in the present study support the hypothesis that the lack of positive effects of Cr yeast supplementation on production performance and egg quality may be related to good management practices, as the birds were not subjected to stressful conditions.