tailieunhanh - Đánh giá việc bổ sung khoáng hữu cơ lên tỷ lệ sống và hiệu quả sử dụng thức ăn trong ương giống cá tra (Pangasianodon hypophthalmus)

Bài viết này trình bày về các loại vi khoáng như Zn, Se, Cu, Fe, Mn và Cr dưới dạng khoáng vô cơ (muối sulphate) hay khoáng hữu cơ (Methionine-khoáng) được bổ sung vào thức ăn để ương cá tra giống 15 ngày tuổi trong thời gian 8 tuần ương nuôi. Sau thí nghiệm, cá được gây cảm nhiễm bằng phương pháp ngâm với vi khuẩn Edwarsiella ictaluri và theo dõi tỉ lệ chết trong 14 ngày. Mời các bạn cùng tham khảo! | Trường Đại học Nông Lâm TP. Hồ Chí Minh 55 Evaluation of dietary supplementation of organic minerals on survivability and feed efficiency in larval rearing of striped catfish Pangasianodon hypophthalmus Duy K. Ho Binh T. T. Vo amp Hung T. Le 1 Faculty of Fisheries Nong Lam University Ho Chi Minh City Vietnam ARTICLE INFO ABSTRACT Research Paper Microminerals of Zn Se Cu Fe Mn and Cr were supplemented in the feed either in inorganic minerals sulfate salt or organic minerals Received August 22 2020 Methionine-mineral at various concentrations over an 8-week period. Revised September 15 2020 Catfish fry 15-day old were fed the experimental diets for 8 weeks. At Accepted October 19 2020 the end of the feeding trial fish were challenged by immersion in a solu- tion of Edwardsiella ictaluri bacteria. The mortality was monitored for 14 days. The results showed that the survival rates of fish fed the organic mineral -supplemented diets were higher than those fed the inorganic mineral -supplemented diets. Treatment 7 supplemented with organic minerals of mg kg Zn mg kg Se and mg kg Cr had the Keywords highest weight gain and survival rates and the lowest FCR there were significant differences in those parameters between treatment 7 and Inorganic minerals the control diet supplemented with inorganic minerals. The variation Larval rearing in fish weight and length of treatment 7 was also lowest and signifi- Organic minerals cantly different P lt from that of the control treatment. After Striped catfish 14 days of bacteria challenge the cumulative mortality of fish in the control treatment was highest and the cumulative mortality of fish in treatment 7 was lowest and the cumulative mortal- ity rates of fish in these two treatments were significantly different P lt from those of the others. The cumulative mortalities of fish in organic minerals treatments were lower than those of fish in inorganic mineral treatments. The study indicated .