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.
Raana Jahanbin; Parisa Yazdanshenas; Mehdi Amin Afshar; Abdollah Mohammadi Sangcheshmeh; Hamid Varnaseri; Mohammad Chamani; Mohammad Hasan Nazaran; Mohammad Reza Bakhtiyarizadeh
Volume 17, Issue 2 , October 2015, , Pages 371-380
Abstract
The effect of zinc Nano-particles (Zn- nano- complex) on bull sperm quality after freeze-thawing process studied. Ejaculates collected from four Holstein bulls twice a week. On the day of semen collection, four ejaculates were pooled and diluted with Bioxcell extender containing 0, 10-6, 10-5, 10-4, ...
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The effect of zinc Nano-particles (Zn- nano- complex) on bull sperm quality after freeze-thawing process studied. Ejaculates collected from four Holstein bulls twice a week. On the day of semen collection, four ejaculates were pooled and diluted with Bioxcell extender containing 0, 10-6, 10-5, 10-4, 10-3, 10-2 molar of zinc Nano-complex and frozen. After thawing, sperm motility and motion parameters, plasma membrane integrity, abnormal morphology, plasma membrane functionality and mitochondrial activity were determined. The proportion of the total and progressive motile sperm, the plasma membrane integrity and proportion of the spermatozoa with abnormal morphology was not different among groups. Zinc Nano-complex groups represented a higher plasma membrane functionality than that of control group. Moreover, our flowcytometric data suggested that spermatozoa in the groups of zinc Nano-complex possessed higher mitochondrial activity as compared with the control group. Mitochondrial activity in 10-2 was higher than the 10-6 group. In conclusion, supplementation of zn Nano-complex, can improve the plasma membrane functionality and mitochondrial activity of bull spermatozoa in a dose dependent manner without any deleterious effect on motility parameters.