CAJ | 학술논문

本试验旨在研究富硒益生菌对罗非鱼幼鱼生长及抗氧化水平的影响。试验选取600尾罗非鱼幼鱼，随机分为5组，每组设3个重复，每个重复随机放养初始体重为（12．40±0．13） g的罗非鱼幼鱼40尾。其中，对照组饲喂硒含量为0．257 mg/kg的基础饲料，其他4组分别饲喂在基础饲料中添加由富硒酵母菌、酵母菌、乳酸菌组成的富硒益生菌的试验饲料。4种试验饲料中富硒酵母菌的添加量折算为硒添加量分别为0（A组）、0．4（B组）、0．6（C组）、0．8 mg/kg（D组），乳酸菌的添加量均为3．04×105 CFU/g，并通过调节酵母菌添加量使4种试验饲料中添加的总活菌数相同。试验期为70 d。结果表明：D组和C组分别在第50～60天和第60～70天阶段表现出最高的特定生长率，并均显著高于对照组（ P＜0．05）。 C组血清谷胱甘肽过氧化物酶（ GPx）活性在第30天和第50天均显著高于A组（ P＜0．05）；对照组血清GPx活性在第60天显著低于其他各组（ P＜0．05）。在第30天，血清过氧化氢酶（ CAT）活性以C组最高、A组最低，各组间均差异显著（ P＜0．05）；对照组血清CAT活性在第60天显著低于A组、B组和C组（ P＜0．05）。 C组血清超氧化物歧化酶（ SOD）活性在第30天和第50天显著高于其他各组（ P＜0．05）。各组罗非鱼的肝脏谷胱甘肽过氧化物酶1（ GPx1） mRNA相对表达量均随饲养天数的延长呈现出上升态势，至第50天达到最高值后开始呈下降的趋势。在第50天，A组和C组的肝脏GPx1 mRNA的相对表达量显著高于其他各组（ P＜0．05），且以C组的值最高。由上述结果可知，在含硒0．257 mg/kg的基础饲料中添加0．6 mg/kg的富硒益生菌（以硒计）可促进罗非鱼幼鱼（体重12～55 g/尾）的生长，提高其抗氧化水平。
본시험지재연구부서익생균대라비어유어생장급항양화수평적영향。시험선취600미라비어유어，수궤분위5조，매조설3개중복，매개중복수궤방양초시체중위（12．40±0．13） g적라비어유어40미。기중，대조조사위서함량위0．257 mg/kg적기출사료，기타4조분별사위재기출사료중첨가유부서효모균、효모균、유산균조성적부서익생균적시험사료。4충시험사료중부서효모균적첨가량절산위서첨가량분별위0（A조）、0．4（B조）、0．6（C조）、0．8 mg/kg（D조），유산균적첨가량균위3．04×105 CFU/g，병통과조절효모균첨가량사4충시험사료중첨가적총활균수상동。시험기위70 d。결과표명：D조화C조분별재제50～60천화제60～70천계단표현출최고적특정생장솔，병균현저고우대조조（ P＜0．05）。 C조혈청곡광감태과양화물매（ GPx）활성재제30천화제50천균현저고우A조（ P＜0．05）；대조조혈청GPx활성재제60천현저저우기타각조（ P＜0．05）。재제30천，혈청과양화경매（ CAT）활성이C조최고、A조최저，각조간균차이현저（ P＜0．05）；대조조혈청CAT활성재제60천현저저우A조、B조화C조（ P＜0．05）。 C조혈청초양화물기화매（ SOD）활성재제30천화제50천현저고우기타각조（ P＜0．05）。각조라비어적간장곡광감태과양화물매1（ GPx1） mRNA상대표체량균수사양천수적연장정현출상승태세，지제50천체도최고치후개시정하강적추세。재제50천，A조화C조적간장GPx1 mRNA적상대표체량현저고우기타각조（ P＜0．05），차이C조적치최고。유상술결과가지，재함서0．257 mg/kg적기출사료중첨가0．6 mg/kg적부서익생균（이서계）가촉진라비어유어（체중12～55 g/미）적생장，제고기항양화수평。
This experiment was conducted to study the effects of selenium-enriched probiotics on growth and antioxidant level of juvenile tilapia ( Oreochromis niloticus) .Six hundred juvenile tilapia with an average initial body weight of (12.40±0.13) g were randomly chosen and distributed into 5 groups with 3 replicates in each group and 40 fish in each replicate.The fish in control group were fed a basal diet containing 0.257 mg/kg se-lenium, and the fish in other four groups were fed experimental diets supplemented with selenium-enriched pro-biotics.The selenium-enriched probiotics were composed by selenium-enriched yeast, yeast and lactic acid bac-teria with different proportions.The supplemental levels of selenium-enriched yeast converted into selenium supplemental levels were 0 ( group A) , 0.4 ( group B) , 0.6 ( group C) and 0.8 mg/kg ( group D) , respec-tively, while the supplemental levels of lactic acid bacteria were all 3.04 ×105 CFU/g, and the supplemental levels of living bacteria were the same by adjusting yeast supplemental level in the 4 experimental diets.The ex-periment lasted for 70 days.The results showed as follows: the highest of special growth rate in the stages of days 50 to 60 and days 60 to 70 was found in groups D and C, respectively, and was significantly higher than that in control group ( P<0.05) .The activity of serum glutathione peroxidase ( GPx) on day 30 and day 50 in group C was significantly higher than that in group A (P<0.05), and the activity of serum GPx on day 60 in control group was significantly lower than that in other groups ( P<0.05) .On day 30, groups C and A had the highest and the lowest serum catalase ( CAT) activity, respectively, and there was significant difference in ser-um CAT activity among all groups ( P<0.05) .The activity of serum CAT on day 60 in control group was sig-nificantly lower than that in groups A, B and C ( P<0.05 ) .The activity of serum superoxide dismutase ( SOD) on day 30 and day 50 in group C was significantly higher than that in other groups ( P<0.05) .The rel-ative expression level of liver glutathione peroxidase 1 ( GPx1) mRNA in each group was firstly increased with feeding time extending; subsequently, it was decreased after reached the highest value on day 50.The relative expression level of liver GPx1 mRNA in groups A and C was significantly higher than that in other groups ( P<0.05) , and group C had the highest value.In conclusion, the supplementation of 0.6 mg/kg selenium-enriched probiotics ( counted with selenium) in the basal diet with 0.257 mg/kg selenium can improve the growth and antioxidant level of juvenile tilapia with the body weight of 12 to 55 g per fish.