Hygienic Value and Mycotoxins Level of Grass Silage in Bales for Horses

Mycotoxins are secondary metabolites of moulds which have adverse effects on humans, animals, and crops and result in illnesses and economic losses. The toxins may occur in storage under conditions favourable for the growth of the toxin-producing fungus or fungi. The highest forage concentration of toxins was found in horizontal storage methods such as bunker silos and feed piles, which were left open to oxygen. In any fermentation storage system, temperature and the presence of moisture is sufficient for toxin production. In a plastic covered storage system, oxygen penetration is slowed but not eliminated. The longer silage is stored, the greater the opportunity for significant fungus growth and toxin contamination. Although the effects of mycotoxins on horses are not well documented in scientific literature, in many situations mycotoxin problems appear to be significant e.g. colic, neurological disorders, paralysis and brain lesions. The aim of this study was to determine the level of mycotoxins in grass silage prepared in bales for horses

Determination of conjugated fatty acid in ovine milk, meat, fat and intestinal digesta

Positional and geometric isomers of geometric isomers of linoleic acid (CLA) were separated from interfering species on commercially available two reversed-phase C18-columns (Nova Pak, Waters) in gradient systems composed of acetonitrile and water, utilizing photodiode array detection. The biological samples were hydrolyzed with 2 M NaOH for 35 min at 85°C. After cooling, the hydrolysates were acidified with 4 M HCl and the free fatty acids were extracted with dichloromethane. The CLA isomers were determined directly using UV detection at 234.5 nm or after pre -column derivatization with 2,4’-dibromoacetophenone in the presence of triethylamine and UV detection at 256 and 235 nm. HPLC system with pre-column derivatization enables more efficient fractionation of the CLA isomers than the direct HPLC system. On the other hand, elimination of derivatization procedure provides a less expensive, more specific and simpler analytical tool for determination of CLA than HPLC method with precolumn derivatization. The presented HPLC methods provide analytical tools for simple quantification of CLA in ovine meat, milk, fat and intestinal digesta samples