F. Cheli

Mycotoxin Contamination in the EU Feed Supply Chain: A Focus on Cereal Byproducts

Mycotoxins represent a risk to the feed supply chain with an impact on economies and international trade. A high percentage of feed samples have been reported to be contaminated with more than one mycotoxin. In most cases, the concentrations were low enough to ensure compliance with the European Union (EU) guidance values or maximum admitted levels. However, mycotoxin co-contamination might still exert adverse effects on animals due to additive/synergistic interactions. Studies on the fate of mycotoxins during cereal processing, such as milling, production of ethanol fuels, and beer brewing, have shown that mycotoxins are concentrated into fractions that are commonly used as animal feed. Published data show a high variability in mycotoxin repartitioning, mainly due to the type of mycotoxins, the level and extent of fungal contamination, and a failure to understand the complexity of food processing technologies. Precise knowledge of mycotoxin repartitioning during technological processes is critical and may provide a sound technical basis for feed managers to conform to legislation requirements and reduce the risk of severe adverse market and trade repercussions. Regular, economical and straightforward feed testing is critical to reach a quick and accurate diagnosis of feed quality. The use of rapid methods represents a future challenge.

Changes in plasmin-plasminogen-plasminogen activator system in milk from Italian Friesian herds

Changes in plasmin, plasminogen and plasminogen activator (PA) throughout the lactation were investigated in individual milk samples obtained from 32 Friesian cows from four commercial herds located in Northern Italy. Herds were chosen to represent four different, yet typical for Italy, diets. Increased levels of plasmin and PA (P < 0.05) were observed with advancing lactation. Plasminogen peaked during the fifth month of lactation. The increased levels of plasmin during the fifth month of lactation are partly due to increased plasminogen, which reflects increased permeability of mammary epithelium. However, the ratio of plasminogen to plasmin decreased with advancing lactation, suggesting accelerated conversion of plasminogen to plasmin. Major differences were observed between herds with respect to plasmin levels. These differences probably reflect differences in diets and management practices. This could be very important for Northern Italy where most of the milk produced is used for cheese manufacture. Plasmin, PA and somatic cell counts (SCC) were negatively correlated with casein/protein with coefficients of −0.38, −0.43 and −0.40, respectively. A significant correlation existed between PA and SCC (r = 0.50). PA was positively correlated with plasmin (r = 0.49).

Effects of feeding calcium salts of long chain fatty acids on milk yield, milk composition and plasma parameters of lactating goats

Abstract Thirty-two goats were fed concentrates, one containing 6% calcium salts of fatty acids. Rations contained equal quantities of Ca and N. Fatty acid calcium salts significantly increased milk fat (from 3.4 ± 0.1 to 3.7 ± 0.2%), but the percentage of short and medium chain fatty acids (C4 to C14) in milk fat decreased (from 37.5 ± 1.0 to 32.2 ± 0.6%). The group fed fatty acid calcium salts had increases in plasma cholesterol (3.5 ± 0.2 vs. 4.3 ± 0.2 mmol/1), phospholipids (2.5 ± 0.1 vs. 2.9 ± 0.1 mmol/1) and gamma-glutamyltranspeptidase (28.9 ± 1.5 vs. 33.5 ± 2.3 U/1).

Nutrition‐Based Health: Cell‐Based Bioassays for Food Antioxidant Activity Evaluation

Food science has progressively evolved and now there are wide evidences that foods have biological activities that are beyond their classical nutritional value. In this field, the antioxidant activity of pure compounds, food, feed, and dietary supplements has been extensively studied and numerous analytical approaches and assay models have been developed, involving various systems from simple chemical assays to animal models and human studies. This article is an overview of different cell-based models that have been used for testing the antioxidant properties of food, feed, and dietary supplements. Advantages, drawbacks, and technical problems to develop and validate suitable, robust, and high-throughput cell-based bioassays for screening food antioxidant activity will be discussed.

Use of the electronic nose as a screening tool for the recognition of durum wheat naturally contaminated by deoxynivalenol: a preliminary approach.

Fungal contamination and the presence of related toxins is a widespread problem. Mycotoxin contamination has prompted many countries to establish appropriate tolerance levels. For instance, with the Commission Regulation (EC) N. 1881/2006, the European Commission fixed the limits for the main mycotoxins (and other contaminants) in food. Although valid analytical methods are being developed for regulatory purposes, a need exists for alternative screening methods that can detect mould and mycotoxin contamination of cereal grains with high sample throughput. In this study, a commercial electronic nose (EN) equipped with metal-oxide-semiconductor (MOS) sensors was used in combination with a trap and the thermal desorption technique, with the adoption of Tenax TA as an adsorbent material to discriminate between durum wheat whole-grain samples naturally contaminated with deoxynivalenol (DON) and non-contaminated samples. Each wheat sample was analysed with the EN at four different desorption temperatures (i.e., 180 °C, 200 °C, 220 °C, and 240 °C) and without a desorption pre-treatment. A 20-sample and a 122-sample dataset were processed by means of principal component analysis (PCA) and classified via classification and regression trees (CART). Results, validated with two different methods, showed that it was possible to classify wheat samples into three clusters based on the DON content proposed by the European legislation: (a) non-contaminated; (b) contaminated below the limit (DON < 1,750 μg/kg); (c) contaminated above the limit (DON > 1,750 μg/kg), with a classification error rate in prediction of 0% (for the 20-sample dataset) and 3.28% (for the 122-sample dataset).

Effects of retinoids on proliferation and plasminogen activator expression in a bovine mammary epithelial cell line

Effects of two natural (retinol and retinoic acid, RA) and one synthetic N-(4-hydroxyphenyl) retinamide (4-HPR) retinoids on proliferation and expression of urokinase-plasminogen activator (u-PA) by bovine mammary epithelial cells were examined. The BME-UV1 established bovine mammary epithelial cell line was used as a model system. All retinoids tested (retinol, RA and 4-HPR) were effective inhibitors of cell proliferation. When cells were cultured in the absence of fetal bovine calf serum (FBCS), inhibition occurred at concentrations as low as 1 nM for all retinoids tested. The effect of retinoids on cell proliferation was not dose-related when cells were cultured in the absence of FBCS. All retinoids (retinol, RA, 4-HPR), when used in the range 1 nM-10 microM (noncytotoxic concentrations), were equally effective and had identical inhibition patterns. Inhibition of cell proliferation by RA was apparent by 6 h and was higher after 24 h in culture. In contrast, when cells were cultured in the presence of FBCS, the effect of RA and retinol on cell proliferation was dose-related. RA and retinol inhibited cell proliferation (P<0.01) when added to the culture medium in concentrations as low as 10 nM and 100 nM, respectively. 4-HPR was inhibitory (P<0.01) in concentrations as low as 1 nM. Higher concentrations of 4-HPR in the range 1 nM-1 microM had no further effect on cell proliferation. None of the retinoids tested, when added to cultures in the presence or absence of FBCS, could completely arrest cell proliferation at noncytotoxic concentrations. RA at 1 microM inhibited (P<0.05) insulin or IGF-I-induced cell proliferation but had no effect (P>0.05) on u-PA mRNA levels or u-PA activity. Furthermore, RA inhibited cell proliferation in the presence of FBCS but had no effect (P>0.05) on u-PA mRNA levels. Thus, retinoids are effective inhibitors of bovine mammary epithelial cell proliferation and this growth inhibition does not seem to correlate with any changes in u-PA mRNA or u-PA activity.

Sampling feed for mycotoxins: acquiring knowledge from food

Abstract The occurrence and control of mycotoxins in feed and food are items of great interest to researchers, producers, manufacturers and regulatory agencies. In order to implement knowledge of control measures for mycotoxins in the entire food production chain, coordinated inspection programmes aimed to check the presence and concentration of mycotoxins in feedingstuffs are recommended by the Commission of the European Communities. Reliability of measured levels of mycotoxins in feed and food is greatly affected by the collection of representative samples. Because of the heterogeneous distribution of mycotoxins, the variability associated with a mycotoxin test procedure usually depends heavily on the sampling plan. European legislation dealing with sampling plans for mycotoxins in foodstuffs has been recently revised. The aim of the following overview is to discuss the role of sampling in mycotoxin-contaminated feed by considering the evolution of legislation dealing with sampling plans for food. A sampling procedure is a multistage process and consists of three distinct phases: sampling, sample preparation and analysis. The variability associated with each step of a sampling procedure and the aspects related to feedstuffs, matrix/mycotoxin combination and level of contamination are discussed.

Expression of urokinase plasminogen activator receptor in resting and activated bovine neutrophils

Changes in urokinase-plasminogen activator (u-PA) and u-PA receptor (u-PAR) expression at the protein and mRNA level in resting neutrophils and in neutrophils activated by phorbol myristate acetate (PMA) were examined. Low amounts of u-PA were found intracellularly or membrane-bound in resting neutrophils. However, incubation of resting neutrophils with purified exogenous u-PA (10 IU/ml) revealed extensive binding of u-PA to cell membranes. Excess amino-terminal fragment of the u-PA molecule, a proteolytically inactive fragment of u-PA (amino acids 1-135) blocked binding of exogenous u-PA to the cell membrane. These results, collectively, indicate that the binding of u-PA is specific and that resting neutrophils have unoccupied u-PA receptors on their cell membrane. Addition of PMA led to an increase (P < 0.01) in total cell-associated, membrane-bound u-PA activity and u-PA mRNA expression by bovine neutrophils. In contrast. PMA increased u-PAR mRNA levels but this was accompanied by a decrease (2.5-fold; P < 0.01) in free, unoccupied u-PA binding sites. No significant effects on total cell-associated or membrane-bound u-PA were found when neutrophils were treated with 4-phorbol 12,13 didecanoate, a phorbol ester that does not activate protein kinase C (PKC). Furthermore, addition of 1-(5-isoquinolinesylphonyl)-2-methlylpiperazine dihydrochloride (H-7), a potent PKC inhibitor, blocked the effect of PMA on total cell-associated u-PA activity. Thus, PKC plays a role in the modulation of u-PA and u-PAR by PMA in bovine neutrophils.

Alpha-Tocopherol Counteracts the Cytotoxicity Induced by Ochratoxin A in Primary Porcine Fibroblasts

The aims of the current study were to determine the half-lethal concentration of ochratoxin A (OTA) as well as the levels of lactate dehydrogenase release and DNA fragmentation induced by OTA in primary porcine fibroblasts, and to examine the role of α-tocopherol in counteracting its toxicity. Cells showed a dose-, time- and origin-dependent (ear vs. embryo) sensitivity to ochratoxin A. Pre-incubation for 3 h with 1 nM α-tocopherol significantly (P < 0.01) reduced OTA cytotoxicity, lactate dehydrogenase release and DNA damage in both fibroblast cultures. These findings indicate that α-tocopherol supplementation may counteract short-term OTA toxicity, supporting its defensive role in the cell membrane.

Differential expression and secretion of alpha1-acid glycoprotein in bovine milk.

alpha1-Acid glycoprotein (AGP) is a lipocalin that is produced mainly by the liver and secreted into plasma in response to infections and injuries. In this study, we evaluated AGP isoforms that can be detected in bovine milk. We found that milk-AGP content is made up of at least two isoform groups, a low MW group (44 kDa) that is produced in the mammary gland (MG-AGP), and a higher MW group (55-70 kDa), that is produced by somatic cells (SC-AGP). Identical SC-AGP isoforms can be found both in milk and blood PMN cells. Analysis of the mammary tissue cDNA showed that the sequence of the MG-AGP isoform is identical to that of plasma AGP. Each group contains several proteins with different MWs and different isoelectric points, as shown by 2D-electrophoresis. The glycosylation patterns of these isoforms were analysed by means of specific lectin binding, to evaluate the degree of sialylation, fucosylation and branching. The MG-AGP glycan pattern was identical to plasma AGP produced by the liver. Several differences were detected, however, between plasma and SC-AGP isoforms, the most evident being the strong degree of fucosylation and the elevated number of di-antennary glycans in SC-AGP. Immunohistochemistry showed that AGP is found in all tissues that make up the mammary gland, but that it is most likely produced for the main part by the alveoli.