Zahra Alimoradi Tamrin; Hassan Darmani Kohi; navid gavi hosseinzadeh
Volume 20, Issue 1 , May 2018, , Pages 1-14
Abstract
In order to investigate the effects of Galbanum essential oil (GEO) and xylanase on performance and intestinal microflora of broiler chicks, a total of 160 one-day old chicks (Ross 308 strain) were used to four dietary treatments based on a completely randomized design in a factorial arrangement. The ...
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In order to investigate the effects of Galbanum essential oil (GEO) and xylanase on performance and intestinal microflora of broiler chicks, a total of 160 one-day old chicks (Ross 308 strain) were used to four dietary treatments based on a completely randomized design in a factorial arrangement. The factors included were xylanase (0 and 0.2 gr/kg of diet) and GEO (0 and 0.1 gr/kg of diet). During the experimental periods (0-10 d, 11-24 d and 25-42 d), body weight gain (BWG), feed intake and feed conversion ratio (FCR) were measured. At days 21 and 42 of age two chicks from each replicate were slaughtered to determine carcass characteristic and ileal microbial populations of E. coli and Lactobacillus. Adding enzymes to the diet increased BWG in growing period and improved FCR in the growing and in the entire period of the experiment. At 21 day of age, GEO supplementation alone or GEO and xylanase as mixed significantly (P
Hossein Manafi Rasi; Mohammad Chamani; Salman Afshar
Volume 16, Issue 2 , October 2015, , Pages 167-178
Abstract
This study was carried out to determine the potential of rumen microorganisms in samples taken from slaughterhouse to produce fibrolytic enzymes and to compare different methods for extraction, concentration and conservation of them. According to the results, the average specific activity of cellulase ...
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This study was carried out to determine the potential of rumen microorganisms in samples taken from slaughterhouse to produce fibrolytic enzymes and to compare different methods for extraction, concentration and conservation of them. According to the results, the average specific activity of cellulase and xylanase were 7.5 and 16.5 U/mg protein respectively. The application of homogenizing and sonication methods to extract rumen content enzymes showed that the former had better performance in the liberation of enzymes. To determine optimum time length for the maximum release of enzymes from solid phases, various time lengths including one, 1.5 and two min were examined. Based on this experiment, one minute appeared the best. To attain a high level of concentration of enzymes obtained from rumen liquor, various procedures were applied. The results indicate that freeze drying and precipitation of enzyme using ammonium sulphate were the best methods, while trichloroacetic acid precipitation turned out to be the most inappropriate method due to improper effect on enzymatic activity. In order to examine the effect of temperature and time length on enzymes activities, some methods including liquid nitrogen, freezing in -70° and freezing in -20° were applied. The comparison of different methods of enzymes conservation indicated that applying liquid nitrogen for long term as well as keeping in the freezer (-70°) for medium term purposes were the best.