engleski

Distribution and activities of oxidative enzymes in the muscles of Lika Pramenka sheep breed, fed with the supplement from button mushroom Agaricus bisporus

Growing concerns about the possible risks for human health caused by the use and/or misuse of antibiotics growth promoters in animal feed led to a ban on their use in the EU (Regulation EC No. 1831/2003). As the latest member of the EU, since 1 July 2013, Croatia has to adjust to the withdrawal of antibiotic growth promoters (in the EU since 2006) and accept the upcoming EU regulations. In order to join the European scientific trends in veterinary medicine Croatia has to determine relevant health criteria as well as the science-based recommendations for the use of the alternatives for antibiotic growth promoters in animal feed. Nutritional and immunomodulatory effects of button mushroom Agaricus bisporus used as supplement have been affirmed and indicate justification of blending those fungi in animal food as a natural alternative to growth promotion antibiotics. The objective of this study was to verify the presence of oxidative enzymes in the skeletal and hind leg muscles of Lika Pramenka sheep breed and to evaluate the effect of button mushroom Agaricus bisporus supplements on histochemical and morphological characteristics of muscles. Four one-year-old sheep, Lika Pramenka breed, were used in this experiment. The dietary groups were controlled, one group was fed on the basal diet and the other group on diets containing 1.5% dry supplement of Agaricus bisporus, during the 6 weeks of winter feeding period. Upon completion of the experiment, after technological slaughter, muscle tissues were obtained from two muscles: longissimus thoracis and quadriceps femoris. Samples from each muscle had been collected and immediately frozen in liquid nitrogen (-196˚ C) and stored at -80˚ C until histochemical and morphological analysis were conducted. Transverse serial sections were cut in cryostat at -20˚ C and transferred to glass coverslips. The sections were stained histochemically for oxidative enzymes: succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G-6-PDH), NADH- and NADPH-diaphorases. LDH reacted stronger in the muscles of animals fed with the supplement of Agaricus bisporus compared with control group of animals, which indicates a stronger synthesis, break-down and transformation of various macromolecular structures. NADH- and NADPH-diaphorases had moderate to strong reaction in quadriceps femoris and slightly weaker reaction in longissimus thoracis muscle. NADH- and NADPH- diaphorases reaction was slightly stronger compared to pair-fed animals. This indicates higher oxidative capacity and higher energy consumption. Negative reaction for G-6-PDH could indicate lower glycogen content in muscle fibres of animals fed with supplement of Agaricus bisporus. Agaricus bisporus is the source of numerous antioxidants, vitamins A, C, D and E, minerals like phosphorus, potassium and iron, and also has a noticeable nutritional value. The data provided by this study illustrates stronger synthesis, break-down and transformation of various macromolecular structures, higher oxidative capacity and higher energy consumption in animals fed with Agaricus bisporus supplement. This study was supported by VIP project No.: 2012-11-17.

oxidative enzymes ; sheep ; button mushroom ; Agaricus bisporus

VIP projekt No.: 2012-11-17