Aflatoxins absorption in the gastro-intestinal tract and in the vaginal mucosa in lactating dairy cows

The objective of the experiment was to monitor plasma levels of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1), G2 (AFG2) and M1 (AFM1) in lactating dairy cows fed a single oral bolus with aflatoxin naturally contaminated corn meal (Trial 1). The possible aflatoxins (AFs) absorption through mucous membranes was also investigated using the vaginal mucosa (Trial 2). In trial 1, seven lactating Holstein dairy cows were given a single oral bolus of a naturally contaminated corn meal assuring an intake of 4.89 mg AFB1, 1.01 mg AFB2, 10.63 mg AFG1 and 0.89 mg AFG2. Blood samples were collected at 0 and 5, 10, 15, 20, 25, 30 minutes after treatment. In trial 2 an aflatoxin dosage similar to that of trial 1 was provided through vaginal implant to eight lactating Holstein dairy cows. Blood samples were collected at 0 and 15, 30, 60, 180, 360 minutes after treatment. Individual milk samples of six milkings, one before and five after treatment, were also collected. Plasma and milk samples were analysed by HPLC for AFB1, AFB2, AFG1, AFG2 and AFM1 contents. In trial 1 AFB1 in plasma peaked (33.6 ng/L) as soon as 20 minutes after treatment. The plasma AFM1 was already detectable at 5 minutes (10.4 ng/L) and peaked at 25 minutes (136.3 ng/L). In trial 2 only AFB1 and AFM1 were detectable in plasma, starting from the first sampling time (15 minutes), with values of 10.7 and 0.5 ng/L, respectively. The AFB1 peaked at 30 minutes (23.9 ng/L). The AFB1 excreted in milk as AFM1 had the highest concentration (203.0 ng/L) in the first milking after treatment and decreased close to the starting values after 36 hours from treatment. The prompt appearance of studied aflatoxins, and their metabolites, in plasma suggests absorption might also take place in mouth or oesophageal mucous membranes, before the rumen compartment. Results support the hypothesis that the cytochrome P450 oxidative system, which is present in these tissues and in leukocytes, could be involved in the conversion of the AFB1 in AFM1. The absorption of AFB1 through the vaginal mucosa confirms the passive diffusion as a probable mechanism for AFB1 absorption

On the location of poles for the Ablowitz-Segur family of solutions to the second Painlev\'e equation

Using a simple operator-norm estimate we show that the solution to the second Painlev\'e equation within the Ablowitz-Segur family is pole-free in a well defined region of the complex plane of the independent variable. The result is illustrated with several numerical examples.Comment: 8 pages, to appear in Nonlinearit

In situ and in vitro nutritional evaluation of rumen-protected lipids

Rumen-protected lipids are a class of products which is increasingly used in ruminant nutrition even if the results are not homogeneous. The different results may be due to different analytical or technological characteristics. Aim of this work was therefore to compare the in situ rumen behaviour of different soaps as well as their in vitro intestinal digestibility

Energy performance assessment of HVAC systems by inspection and monitoring

The paper discusses the collection and processing of energy performance data as part of the inspection of HVAC systems, aimed at identifying technically feasible and cost-effective Energy Conservation Opportunities (ECO), as required by EPBD. Case studies developed by the HARMONAC project have shown that low-cost or no-cost ECO’s - mostly related to system operation and management - can be identified with an effective system monitoring. Building Management Systems (BMS) may be a powerful tool for this task, provided their HW and SW architecture is designed with adequate attention to energy monitoring. Dedicated instrumentation – such as electricity meters and temperature loggers – may also be employed as an alternative / integration to BMS monitoring. The paper also discusses the application of data analysis tools – such as “carpet plots” and “energy signatures” – to the identification of component malfunctioning, control problems, inadequate maintenance, or system schedule optimization, and to the evaluation of achieved energy savings

In vivorelease of aflatoxin B1 bound to different sequestering agents in dairy cows

Nine lactating dairy cows, producing 31.08±5.00 kg of milk/cow/day and fed with a Total Mixed Ration (TMR) with an intake of 22.3±0.8 Kg s.s./cow, were used to investigate the resistance of the AFs-SA complex in the rumen and in the gastro-intestinal tract. Two commercial sequestering agents Atox® and Mycosorb® were used. The AFB1 was also mixed to a rumen fluid (R-SA). AFB1 sequestered by Atox®, Mycosorb® and by R-SA were then fed to cows before the morning meal. Milk samples were collected for 6 consecutive milkings and analyzed for AFM1 content. The in vitro binding capacity of the two SA were 94.2% for Atox®, 84.3% for Mycosorb® and 71.86% for the R-SA. Both Atox® and Mycosorb® released some of the sequestered AFB1 determining an increase of the AFM1 in milk as soon as in the 1st milking from oral drenching (4.23±7.33; 23.60±8.23 and 46.06±39.84 ppt for Atox®, Mycosorb® and R-SA respectively). The AFM1 (ng/cow) in milk at the 4th milking was lower (66.04, 661.77 and 1613.04; P<0.05) in Atox® and Mycosorb® than R-SA, respectively. The percentage release of bound AFB1 were 1.63% for Atox®, 20.27% for Mycosorb® and 50.48% for R-SA

Advances in biomimetic collagen mineralisation and future approaches to bone tissue engineering

With an ageing world population and ~20% of adults in Europe being affected by bone diseases, there is an urgent need to develop advanced regenerative approaches and biomaterials capable to facilitate tissue regeneration while providing an adequate microenvironment for cells to thrive. As the main components of bone are collagen and apatite mineral, scientists in the tissue engineering field have attempted in combining these materials by using different biomimetic approaches to favour bone repair. Still, an ideal bone analogue capable of mimicking the distinct properties (i.e., mechanical properties, degradation rate, porosity, etc.) of cancellous bone is to be developed. This review seeks to sum up the current understanding of bone tissue mineralisation and structure while providing a critical outlook on the existing biomimetic strategies of mineralising collagen for bone tissue engineering applications, highlighting where gaps in knowledge exist

Mucosal absorption of aflatoxin B1 in lactating dairy cows

The objective of this experiment was to monitor plasma levels of aflatoxin B1 (AFB1) aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2) and aflatoxin M1 (AFM1) in lactating dairy cows fed afltaoxin contaminated corn. Seven lactating Holstein cows were given a bolus of a naturally contaminated corn meal assuring an intake of 4.9mg AFB1, 1.01 mg AFB2, 10.63 mg AFG1 and 0.89 mg AFG2. Vitamin A, at 1,000,000 IU, was also added as a biomarker of intestinal absorption. Blood samples were collected at 0, 15, 30, 60, 120, 180, 270 and 360 min after bolus. Plasma was analyzed by HPLC for AFB1, AFB2, AFG1, AFG2 and AFM1 concentrations. Within the considered time points, the peak plasma AFB1 concentration was obtained as soon as 15 minutes from drenching. The plasma AFM1 concentration was considerable as early as the first collection (15 minutes) and peaked at 270 minutes indicating both a rapid absorption of AFB1 through the rumen wall and metabolization into AFM1 in liver. The plasma palmitate level suggests the intestinal contribution to the aflatoxin plasma level after 120 min

Effect of the presence of two commercial adsorbents in animal feed on Aflatoxin B1 determination by ELISA kit test.

A rapid AFB1 detection method by ELISA kit test was used on feedstuff samples, and compared to an HPLC method, to verify if the presence of clay-adsorbent (SA) could cause erroneous quantification of the toxin. Samples were obtained using two AFB1-contaminated feedstuffs (7.92 and 17.58 µg/kg for low and high contaminated feeds; LC and HC respectively), added either one of two commercial SAs (Atox® and Myco AD) and three different inclusion doses (0, 10 and 20 g/kg, respectively for CTR, 1% and 2% doses). The HPLC and ELISA data were compared in CTR samples with a paired t-test. The AFB1 recoveries, performed with ELISA, were analysed as a completely randomized design using a 2×2×3 factorial arrangement. The ELISA method tended to underestimate the AFB1 concentrations with respect to the HPLC method, both in HC (P=0.050) and in LC (P<0.001) feedstuffs. A more drastic reduction (P<0.001) was observed when SAs were included in the two feedstuffs. In particular, Atox® determined an AFB1 recovery of 15,5% in HC and 7,6% in LC (1% dose) and of 11,1% in HC and 8,4% in LC (2% dose). Less severe penalisation were observed when Myco AD was added to feeds