Research & Development – Research Briefs
ambient pH (7.99) of experimental seawater by bubbling food-grade CO2 to obtain the desired pH levels as expected by the year 2100. Survival of H. asinine postlarvae was negatively affected by reduced pH. Mean shell lengths of postlarvae also differed significantly among treatments and across exposure period (P = 0.000 for both). Our results suggest that growth and survival of postlarval H. asinine was found to be sensitive to reduced pH of seawater. This implies that future decrease in pH unit of the world’s oceans will most likely threaten the natural population of this economically important species.
Fish and Shellfish Immunology, Vol 43, 1 Dietary supplementation with Bacillus subtilis, Saccharomyces cerevisiae and Aspergillus oryzae enhance immunity and disease resistance against Aeromonas hydrophila and Streptoccocus
iniae infection in juvenile tilapia, Oreochromis niloticus. MARINA KEIKO P. IWASHITA, IVAN B. NAKANDAKARE, JEFFERY S. TERHUNE, THERESA WOOD, MARIA JOSÉ T. RANZANI-PAIVA A feeding trial was conducted to investigate the effects of dietary administration of probiotic with Bacillus subtilis, Aspergillus oryzae and Saccharomyces cerevisiae on growth, innate immune response, He- mato-immunological parameters and disease resistance of Nile tilapia, Oreochromis niloticus. Animals were distributed in three equal groups, each of five replicates, and received one of the following experimental diets for four weeks: Control, non-supplemented diet; 5 g kg−1 probiotic mixture (B. subtilis 1.5 × 109 CFU g−1, S. cerevisiae 109 CFU g−1 and A. oryzae 2 × 109 CFU g−1); and 10 g kg−1 probiotic mixture (B. subtilis 3.0 × 109 CFU g−1, S. cerevisiae 2.0 × 109 CFU g−1 and A. oryzae 4.0 × 109 CFU g−1). The respiratory burst activity, white blood cells and hematological parameters were evaluated after four, five and six weeks of feeding. At the end of the growth trial, fish were sampled for intestinal microbiology and challenged by intraperitoneal injection of LD50 concentration of
Aeromonas hydrophila and Streptococcus iniae. Mortality was recorded for the following three weeks. Results showed that administration of the probiotic had no significant effect on the growth rates of Nile tilapias, although the fish fed probiotics had better feed conversion. Respiratory burst activity, erythrocyte fragility and levels of white blood cells were significantly improved in tilapias fed diet supplemented with probiot- ic levels (P < 0.05), which may exhibit up-regulating effects on tilapia immune parameters. The cumulative mortality after A. hydrophila and S. iniae challenge decreased in tilapias fed with probiotic (P < 0.05). The present study demonstrated the potential of B. subtilis, S. cerevisiae and A. oryzae combined as beneficial dietary probiotic in juvenile O. niloticus.
Journal of the World Aquaculture Society, Vol 46, 1 Effects of different diets on body biochemical composition of the four-
sided sea cucumber, Isotichopus badionotus, under culture conditions M ZACARIAS-SOTO AND MA OLVERA-NOVOA The objective of this study was to test different commercial diets and meas-
ure their effects on the growth and biochemical composition of four-sided sea cucumber, Isostichopus badionotus. Three diets were used: diet A (37.66% protein and 7.27% lipids), diet B (20.09% protein and 3.34% lipids), and diet C (14.83% protein and 2.45% lipids). No differences in weight gain among treat- ments were observed; however, sea cucumbers fed diet C presented lower carcass protein levels. Lipid content decreased in all treatments compared to the initial values. I. badionotus maintained its initial body profile regardless of the fatty acids composition of the diets; however, the body level of saturated fatty acids increased significantly in animals fed diets B and C. The concentra- tion of polyunsaturated fatty acids was very low in all diets; nevertheless, the sea cucumbers maintained their corporal levels of C20:2, C20:3n-3, C20:4n-6, C20:5n-3, and C22:6n-3. They are also capable of elongate and desaturate 16C and 18C fatty acids supplied in the diet. These results suggest that I. badionotus is capable of maintaining its biochemical composition when fed diets contain- ing at least 20 per cent protein and low levels of lipids. FF
“Fishers underwater video cameras brave the dangerous sites, so you don’t have to”
-Jack Fisher, President
Only $19,995 SeaOtter-2
ROV
Very Rugged and Compact
Control Box with Built-in Monitor
“Fishers underwater video products are cost effective tools for underwater search and inspection. The line includes low-cost mini cameras, dropped video systems, towed cameras, and powerful ROVs with scanning sonar onboard. Fishers has an underwater camera that will fit your application and your budget.”
Scan-650
Scanning Sonar
$6,995
www.fishfarmer-magazine.com CT-1
Cable Tracker with Signal Injector
$14,495 $12,995 $19,995
Proton 4 Marine
Call for a free catalog or visit our web site:
jwfishers.com Pingers
Side Scans
Magnetometer Receivers
Pingers and
$695
Metal Detector $9,495
Boat-towed 1953 County St., E. Taunton, MA 02718 USA • (800)822-4744 (508)822-7330 • FAX: (508)880-8949 • email:
jwfishers@aol.com •
www.jwfishers.com 55 P12
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60