ahmad pirali

Over the past few years, an immune system has been discovered in bacteria that has led to the development of a powerful gene-editing technique called CRISPR/Cas9 (Clustered regularly interspaced short palindromic repeat). Because of its simplicity and flexibility, CRISPR technology has been widely used in many fields of research based on genome editing in animal, microbial, medical, pharmaceutical and plant sciences. This article discusses the history, basic mechanisms and applications of the CRISPR/Cas9 system and its potential for improving the performance of domestic animals. Given the widespread acceptance of this technology by all animal genome editing institutes in the world, as well as the advances that have been made in its evolution and enhancement of capabilities, it is obvious that the CRISPR/Cas9 system will soon undergo a dramatic transformation in the creation of lines and breeds with desired traits. In addition, extensive advances are being made to improve the capabilities and efficiencies of this technology for on-target genome editing as well as reducing the chances of editing off-target regions.

The present study aimed to investigate the different levels of Galacto oligosaccharide prebiotic on growth performance and intestinal morphology of Carassius auratus gibelio. A number of 240 baby fish with the mean weight of 4.88 ±0.28 g were divided into four groups. The first group as the control was fed with basic diet (having no Galacto oligosaccharide) while the second, third, and fourth groups were fed with the diets containing 0, 0.5, 1 and 2 % Galacto oligosaccharide for six weeks. At the end of the test, the growth markers were calculated (including final weight, specific growth rate, and food conversion ratio). Then, intestinal biopsy was conducted and the mean length, width, and absorption surface of intestinal villus were measured in each treatment. The results indicated a significant effect of treatment with 2% Galacto oligosaccharide on villus length, width and absorption surface in Carassius auratus gibelio (P<0.05). However, no significant difference was found between treatments in terms of growth parameters. Due to the significant effect of Galactooligosaccharide prebiotic on the increase of absorption surface in Carassius auratus gibelio as well as the relative increase of growth parameters int he fish fed with Galacto oligosaccharide than the control treatment, it seems that this substance can be used as a suitable stimulating factor of growth and feeding in the diets of red ornamental fish.