نوع مقاله : مقاله پژوهشی
نویسندگان
گروه تکثیر و پرورش آبزیان، دانشکده شیلات و محیط زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، گلستان
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Probiotics as alternatives to chemicals and antibiotics have proven to be effective in promoting successful aquaculture. They can improve water quality, increase tolerance to stress, generate high-quality livestock, etc. The present study aimed to investigate the effect of adding Lactobacillus rhamnosus PTCC 1637 to water on the intestinal tissue of rainbow trout, Oncorhynchus mykiss. This experiment was performed in three treatments including 1: days 1 to 7; 2: days 1 to 20; and 3: days 1 to 60, by adding the bacterium at 106-107 CFU/mL into the water and also a control group. The above mentioned concentrations of the bacterium in group 1 were added on days 1, 3, and 5; in group 2, at every two days; and in group 3, from 1 to 20 on every other day, then from 20 to 60, once in four days. At the end of the experiment, intestinal alteration was examined. The results showed that the highest length (247.2 µm) and width of intestinal villi (70.6 µm) were related to the hatched egg group from 1 to 60 days (hatched egg part), while the lowest in the control group. There was no significant difference between the average width and length of the intestinal villi in other treatments compared to the control group. In general, the use of bacteria in the eyed eggs group (days 1 to 60 at a concentration of 107 CFU/mL) showed a more favorable result than in the alevin and fry groups. Finally, the direct addition of probiotics to the water effectively improved intestinal morphology in O. mykiss.
کلیدواژهها [English]
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