LAUSR

One of the main goals of the lamb meat production industry is to improve the meat quality with a higher growth rate and with lower feed consumption. Therefore, both meat and livestock industries have been constantly seeking new ways to achieve this main goal. However, consumers’ preferences play an important role in specifying the quantity and quality standards of lamb meat in the market and often act as a limiting factor for these industries (20). In last decades, the use of both natural and synthetic silicate minerals and by-products of the fermentation industry in animal nutrition has increased mainly due to their positive effects on animal performance and health. Clinoptilolite, natural hydrated aluminosilicates, and brewer’s yeast, a by-product of breweries, are two of these materials that have been increasingly used in animal nutrition. Moreover, some processes such as the activation of clinoptilolite and inactivation of brewer’s yeast are necessary to increase the adsorption capacity of clinoptilolite and eliminate further fermentation of brewer’s yeast after consumption (2, 5). While activated and micronized clinoptilolites, known as good adsorbent and toxin binders, are primarily used for detoxfiying the heavy metals, O2, reactive oxygen species (ROS) and aflatoxins; the inactivated brewer’s yeast is mostly used to increase the dry matter intake and nutrient digestibility, regulate the rumen pH, and reduce amonia in ruminants (3, 9, 12, 16). Previous studies on meat production industry have primarily focused on improving the average daily gain (ADG) and the feed conversion ratio in ruminants (6, 7, 14). The extent of the performance enhancement 1) The present study was supported by the Republic of Turkey, Ministry of Agriculture and Forestry, General Directorate of Agricultural Research (Project No: TAGEM/HSGYAD/B/19/A4/B2/1026). The authors would like to thank Orgamin Ltd. Co. and Atayem Ltd. Co. for their contribution. Effect of activated clinoptilolite and inactive brewer’s yeast mixture on loin eye muscle and body indexes in fattening period1)