Aflatoxin M1 (AFM1) residues in milk are regulated in many parts of the world and can cost dairy farmers significantly due to lost milk sales. Additionally, due to the carcinogenicity of this compound contaminated milk can be a major public health concern. Thirty-four lactating dairy cows were utilised to investigate the relationship between somatic cell counts (SCC), milk yield and conversion of dietary aflatoxin B1 (AFB1) into milk AFM1 (carryover (CO)). The AFM1 in milk increased as soon as the first milking after animal ingestion with a pattern of increment up to the observed plateau (between 7th and 12th days of AFB1 ingestion). There was a significant (P , 0.01) effect of the milk yield whereas no effect could be attributed to the SCC levels or to the milk yield 3 SCC interaction. Similarly, the main effect of milk yield was also observed (P , 0.01) on the total amount of AFM1 excreted during the ingestion period. Although the plasma concentration of gamma-glutamyl transferase was significantly affected by aflatoxin administration, levels of this liver enzyme were within the normal range for lactating dairy cows. The current data suggest that milk yield is the major factor affecting the total excretion of AFM1 and that SCC as an indicator of mammary gland permeability was not related to an increase in AFM1 CO.

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Dietary starch from feed grains represent the major energy-yielding sources in diets for large animals and starch effective digestion has a great impact on animal energy intake for meeting the substantial energy requirement to improve meat or milk productions. In general, site, extent and rate of starch digestion are affected by intrinsic and external factors that can be interrelated and are thus not easily defined. As a consequence, research to obtain a deeper knowledge on how starch chemical and structural compositions may affect starch digestion potential of feed grains and therefore their nutritional value has progressed recently. The objectives of this review are: (1) to give an overview on inherent starch primary structures and interactions with other compounds within feed grains; (2) to discuss factors affecting starch digestion potential in feed grains; (3) to explore starch digestion mechanism, and linkages with animal performances, both for swine and ruminants. The criticism of methods commonly used to estimate starch digestibility from feed grains for swine and ruminants are also discussed.

The main quality traits of corn silages differed throughout the entire silo face. Minimization of the area exposed to risk of air penetration represents the best strategy to preserve the nutritional value and safety of corn silages. PFA allowed a clusterization of original variables into 11 PCs, appearing able to discriminate well and poorly preserved corn silages.