Biogenic amines and mycotoxins concentrations in baled silage from organic and conventional farms / Concentrações de aminas biogênicas e micotoxinas em silagem embalada de fazendas orgânicas e convencionais

The aim of the current study was to investigate biogenic amines and mycotoxins concentrations in baled silage (mainly Poaceae family grasses) prepared in organic and conventional farms and to relate these parameters to fermentative parameters. The mean dry matter (DM) content was 364.10±93.31 and 424.70±95.93g/kg in the silage from organic and conventional farms respectively. The silage samples from organic farms had 17.00% higher (P≤ 0.05) tyramine (TY) than the silage from conventional farms. Conventional farm samples were characterized by 46.00% higher histamine (HIS) (P≤ 0.05), 9.80% higher putrescine (PUT) (P≤ 0.05), 17.30% higher cadaverine (CAD) (P≤ 0.05). Aflatoxins (AFL) (total) and zearalenone (ZEN), T-2/HT-2 concentrations were higher respectively 16.00% (P≤ 0.05) and 13.40% (P≤ 0.05), 1.80% (P≤ 0.05) in the silage prepared in organic farms. Deoxynivalenol (DON) concentration was higher 42.40% (P≤ 0.05) in silage from conventional farms. Volatile fatty acids (VFA), lactic acid, ethanol, pH and ammonia nitrogen showed that the silage samples from organic and conventional farms were of good quality. Our study suggests differences in biogenic amine formation or mycotoxins content in silage from organic and conventional farming, but, overall, the measured values are too low to be relevant for animal health. Furthermore, these differences might as well be due to the difference in dry matter content and plant maturity between the organic and conventional silage samples.(AU)

O objetivo do presente estudo foi investigar concentrações de aminas biogênicas micotoxinas em silagem embalada (principalmente gramíneas da família Poaceae) preparada em fazendas orgânicas e convencionais e relacionar esses parâmetros a parâmetros fermentativos. A massa seca média (MS) foi 364,10±93,31 e 424,70±95,93g/kg na silagem de fazendas orgânicas e convencionais, respectivamente. As amostras de silagem de fazendas orgânicas tinham 17% a mais de tyramina (TY) (p≤ 0,05) que as de fazendas convencionais. As amostras de fazendas convencionais foram caracterizadas por histamina (HIS) 46,00% mais alta (P≤ 0,05), 9,80% putrecina (PUT) mais alta (P≤ 0,05), 17,30% de cadaverina (CAD) mais alta (P≤ 0,05). Aflatoxnas (AFL) (total) e zearalenone (ZEN), T-2/HT-2 tinham concentrações mais altas em respectivamente 16,00% (P≤ 0,05) e 13,40% (P≤ 0,05), 1,80% (P≤ 0,05) na silagem preparada em fazendas orgânicas. Deoxinivalenol (DON) tinha concentração mais alta 42,40% (P≤ 0,05) na silagem de fazendas convencionais. Ácidos graxos voláteis (AGV), ácido lático, etanol, pH e nitrogênio de amônia mostraram que as amostras de silagem de fazendas orgânicas e convencionais tinham boa qualidade. Nosso estudo sugere diferenças na formação biogênica de amônia ou micotoxinas em silagem de fazendas orgânicas ou convencionais mas, em geral, os valores medidos foram muito baixos para serem relevantes à saúde animal. Ademais, essas diferenças podem ser devido à diferença na matéria sólida e maturidade da planta entre as amostras de silagem orgânica e convencional.(AU)

Antioxidant status of blood and liver of turkeys fed diets enriched with polyunsaturated fatty acids and fruit pomaces as a source of polyphenols.

It was hypothesized that dietary polyphenol-rich fruit pomaces can improve the antioxidant status of both diets and the tissues of turkeys fed such diets. Turkeys were fed diets containing a cellulose preparation (C) or 5% dried apple pomace (AP), blackcurrant pomace (BCP), strawberry pomace (SP) and seedless strawberry pomace (SSP). Blood and liver biochemical parameters were determined in 7 birds from each experimental group slaughtered at 15 weeks of age, after 5 weeks of feeding diets containing soybean oil and linseed oil (approx. 1:1 ratio). Dietary linseed oil added to diets at 2.5% lowered the n-6/n-3 PUFA ratio from approx. 7:1 to below 2:1, thus reducing the antioxidant properties of diets measured using DPPH, ABTS and photo-chemiluminescence assays, compared with diets containing only soybean oil and administered to birds in the first phase of feeding. Fruit pomaces, in particular SSP with the highest polyphenol content (32.81 g/kg) and the highest antioxidant activity (256.4 µM Trolox/g), increased the antioxidant capacity of turkey diets. In comparison with the control group, the dietary treatments with fruit pomaces improved blood antioxidant parameters, including catalase activity (groups AP and BCP), the total antioxidant capacity of hydrophilic (group AP) and lipophilic (groups AP, SP, and SSP) compounds, peroxide levels (groups AP and SSP) and antioxidant capacity measured by the FRAP (ferric reducing antioxidant power of plasma) assay (groups AP, BCP and SSP). Significantly lower concentrations of both vitamin E and thiobarbituric acid reactive substances (TBARS) were noted in the livers of turkeys fed all diets with dried fruit pomaces.

The effect of different dietary levels of vitamin E and selenium on antioxidant status and immunological markers in serum of laying hens.

The effect of different dietary levels of selenium (Se) and vitamin E on egg production, the antioxidant status and the immune system response of hens was investigated in the current study. A total of 32 Lohman Brown hens were divided into four groups and were fed diets with 5% of soybean oil and two levels of Se (0.15 and 0.30 mg/kg) and vitamin E (30 and 60 mg/kg). During 10 weeks of experimental feeding, the body weights of hens and egg production were similar in all dietary treatments, but a higher Se content of diets contributed to a significant increase in egg weight. A higher vitamin E level significantly increased alpha-tocopherol concentrations (2.71 vs. 2.05 microg/mL, p = 0.001), superoxide dismutase (SOD) activity (43.3 vs. 39.9 U/mL, p = 0.049) and the ferric reducing ability of serum (FRAP) (123.0 vs. 105.7 micromol/L, p = 0.029). A higher Se content increased the concentrations of ascorbic acid (0.309 vs. 0.073 microg/L, p = 0.001), retinol (1.48 vs. 1.15 microg/mL, p = 0.001) and alpha-tocopherol (2.86 vs. 1.90 microg/mL, p = 0.001), the activity levels of catalase (3.40 vs. 2.98 U/L,p = 0.010) and SOD (43.4 vs. 30.8 U/mL, p = 0.040) as well as the total antioxidant status (TAS) of serum (0.38 vs. 0.28 mmol/L, p = 0.026). There were no significant differences in the concentrations of tumor necrosis factor-alpha (TNF-a) and interleukin-6 (IL-6) between treatments, while a higher vitamin E content of diets increased serum immunoglobulin A (IgA) concentrations (370.6 vs. 321.3 microg/mL, p = 0.026). Higher dietary levels of vitamin E and Se increased the serum concentrations of retinol (1.66 vs. 2.20 microg/mL, p = 0.013) and a-tocopherol (3.33 vs. 1.71, p = 0.014), but they had no effect on the other physiological parameters. It is recommended that the levels of both supplements, Se and vitamin E, be increased in laying hen diets as they have a beneficial effect on the serum concentrations of retinol and alpha-tocopherol.