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The objectives of this study were to evaluate the exposure to a diet naturally contaminated with mycotoxins on lactation performance, animal health, and the ability to sequester agents (SA) to reduce the human exposure to AFM 1. Sixty healthy lactating Holstein cows were randomly assigned to two groups: naturally contaminated diet without and with the addition of a SA (20 g/cow/d AntitoxCooPil® −60% zeolite-40% cell wall-). Each cow was monitored throughout lactation. The concentration of aflatoxin B 1 (AFB 1) in feed and M 1 (AFM 1) in milk, health status, and productive and reproductive parameters were measured. AFB 1 concentration in feed was very low (2.31 μg/kgDM). The addition of SA reduced the milk AFM 1 concentrations (0.016 vs. 0.008 μg/kg) and transfer rates (2.19 vs. 0.77%). No differences were observed in health status, production and reproduction performance. The inclusion of SA in the diet of dairy cows reduce the risk in the most susceptible population. • Toxic effects of a diet naturally contaminated with mycotoxins was studied. • The ability to sequester agents to reduce the aflatoxin exposure was also studied. • No differences were observed in productive and health indicators. • Sequester agents in the diet of dairy cows reduced the human exposure. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effect of three alfalfa pasture herbage allowances on milk yield and composition during autumn–winter grazing season on early autumn calving dairy cows. Eighteen multiparous Holstein dairy cows were assigned to one of three treatments in a 3×3 Latin square design: low herbage allowance (14 kg DM/cow; LHA), medium herbage allowance (27 kg DM/cow; MHA) and high herbage allowance (41 kg DM/cow; HHA). Dry matter disappearance was lower at LHA although remained similar between MHA and HHA ( P <0.05). However, as herbage allowance (HA) increased, lower grazing efficiencies (as the proportion of material removed) were registered ( P <0.05). Total dry matter intake (DMI; kg/d) was also lowest for LHA and similar between the other two treatments ( P <0.05). Milk yield, 4%FCM, milk fat (g/kg) and casein (g/kg) tended to increase from LHA to HHA ( P <0.10). Cows at LHA tended to loss weight whilst cows at MHA and HHA had a tendency to increase BW according the season progressed ( P <0.10). In summary, managing cows at HHA will allow cows to a slightly increase in individual milk production and BW gain but in detriment of herbage utilization and potentially, milk production per hectare. [ABSTRACT FROM AUTHOR]

Abstract: A stochastic simulation model was developed to carry out the first quantitative risk exposure assessment of the mycotoxin level in cow’s milk produced in Argentina. The prevalence and concentration of aflatoxin M1 (AFM1), deoxynivalenol (DON) and zearalenone (ZEA) were modeled at various stages through milk processes complying with Argentinean practices. Concentration of AFM1 (0.059ppb), DON (0.338ppb) and ZEA (0.125ppb) in dairy milk were estimated. The proportion of feed samples that exceeded the maximum level accepted by European regulations for AFB1, DON and ZEA were estimated at 25.07%, 0.0% and 8.9%, respectively. The percentage of milk samples that exceeded the maximum level accepted for AFB1 by the MERCOSUR (0.5ppb) and the European Union regulations (0.05ppb) were 0.81 and 32.65, respectively. The probability distribution of AFM1 concentration in milk was affected by the carry-over rate equations applied in the model. Mycotoxin levels in corn silage and concentrated feeds were the factors most correlated with mycotoxin concentrations in milk. Therefore, agricultural practices, crop management and feed production require prompt attention regarding mycotoxin issues. [Copyright &y& Elsevier]

The objectives of this study were to assess aflatoxin M 1 (AFM1) contamination in bulk tank milk, and to further identify the risk factors associated with the presence of AFM1 in raw milk in Argentina. The presence of AFM1 was investigated in 160 bulk tank milk samples collected from farms located in the most important milk production region in Argentina during one year (four seasons). Samples were analysed using immunoaffinity column (IAC) cleanup and UHPLC-MS/MS method for determining AFM1 at low levels of concentrations (LOQ = 0.003 μg L −1 ). A survey about the potential factors associated with the presence of AFM1 in milk was performed directly in the field through a questionnaire applied to the farmers. Chi-square and logistic regression were performed with presence of AFM1 in milk as dependent variable, and potential risk factors as independent variables. Incidence of AFM1 in raw milk was 38.8% and, in all samples, AFM1 levels were lower than the Southern Common Market (MERCOSUR) Regulation (maximum level accepted = 0.5 μg L −1 ). Commercial feed consumption (OR = 4.630, P = 0.001), soybean expeller consumption (>0.95 kgDM/cow) (OR = 3.542, P = 0.019), and cotton seed consumption (>1.5 kgDM/cow) (OR = 2.949, P = 0.089) were associated with the incidence of AFM1 in raw milk. Despite the incidence and the level of AFM1 in milk produced and commercialized in Argentina is not a serious problem for public health. The farm breeding intensification and the supplementation with commercial feed, soybean expeller, and cotton seed seems to be the risk factors that impacts on the AFM1 milk contamination. Therefore, Argentina should improve its monitoring program on mycotoxins in animal feed and milk and improve the management practices in farms. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to evaluate dry matter intake (DMI), milk yield, and milk composition from feeding rations that contained different sources of genetically modified whole cottonseed to Argentinean Holstein dairy cows. Twenty-four lactating multiparous Argentinean Holstein dairy cows were used in 2 experiments with a replicated 4 x 4 Latin square design, with cows averaging 565 kg body weight and 53 d in milk at the beginning of the experiments. Treatments in Experiment 1 were: Bollgard cotton containing the cry1Ac gene, Bollgard II cotton containing cry1Ac and cry2Ab genes, Roundup Ready cotton containing the cp4 epsps gene, and a control nongenetically modified but genetically similar cottonseed. In Experiment 2, two commercial sources, a parental control line, and the transgenic cotton containing both cry1Ac and cp4 epsps genes were used as treatments. All cows received the same total mixed ration but with different whole cottonseed sources. Cottonseed was included to provide 2.50 kg per cow daily (dry matter [DM] basis) or about 10% of the total diet DM. The ingredient composition of the total mixed ration was 32% alfalfa hay, 28% corn silage, 22% corn grain, 17% soybean meal, and 2% minerals and vitamins. In addition, genomic DNA was extracted from a subset of milk samples and analyzed by polymerase chain reaction followed by Southern blot hybridization for small fragments of the cry1Ac transgene and an endogenous cotton gene, acp1. No sample was positive for transgenic or plant DNA fragments at the limits of detection for the assays following detailed data evaluation criteria. The DMI, milk yield, milk composition, body weight, and body condition score did not differ among treatments. Cottonseed from genetically modified varieties used in these studies yielded similar performance in lactating dairy cows when compared to non-transgenic control and reference cottonseed. [ABSTRACT FROM AUTHOR]

Objective: To develop a bedside mental status examination to assess the behavioural effects of damage to the frontal lobes. Design: A prospective clinical comparison of patients with cerebral lesions of different locations. Subjects: A total of 118 subjects were examined: 27 patients with cerebral lesions confined to the frontal lobes, 25 patients with cerebral lesions without involvement of the frontal lobes, 18 patients with mixed frontal/nonfrontal lesions, and 48 normal control subjects. Measures: Twenty-three mental status tests, clinical examinations and rating scales that had been reported as indicative of frontal lobe function were brought together. By statistical analysis, 12 tests and a neurobehavioural rating scale were selected. These constitute the Frontal Lobe Score (FLS). Results: The FLS detected pure frontal lesions with a sensitivity of 77.7%. It discriminated patients with frontal lesions from normal control subjects with a specificity of 100%. Differentiation from patients with nonfrontal lesions was obtained with a specificity of 84%. Conclusion: The Frontal Lobe Score is a useful screening instrument for the clinical detection of effects of frontal lobe damage. [ABSTRACT FROM AUTHOR]

In Argentine grazing systems, additional supply of energy and protein is needed to balance the diet during periods of pasture shortage in winter. Three protein meal sources were evaluated, in terms of milk yield and composition, for grazing dairy cows receiving a supplementary PMR. Thirty three multiparous cows, averaging 75 ± 15 DIM, and over 7000 L/cow in previous lactations, were randomly assigned to 3 treatments: SM= soybean meal, L-SuM= sunflower meal-low-protein and CM= canola meal, in a continuous split-plot design with covariance analysis. The diets were isoenergetic (1.82 Mcal NEL) and isonitrogenous (17% CP), and were formulated (DM basis) with 17 % pasture and 83% of a PMR containing corn silage, alfalfa hay, corn grain, minerals and vitamins premix and the corresponding protein meal. The CP concentrations were 28, 35 and 41% for L-SuM, CM and SM, and represented 25, 20 and 15% total diet DM, respectively. Table 1 shows milk yield and composition for all treatments. The L-SM had the lowest response in terms of milk yield, but the highest in milk fat percentage, thus suggesting concentration effects. On the other hand, CM produced the lowest protein concentrations, probably because of differences in dietary amino acid supply to the mammary gland. Milk urea concentration was lowest for CM. [ABSTRACT FROM AUTHOR]