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During spring 2006-2009, eggs were collected for analysis of total thiamine from gravid rainbow smelt (Osmerus mordax) captured in each of the Great Lakes and two other waters as references for comparison. Mean standard length (mm ± standard error) of gravid females significantly differed between sample waters, with the Atlantic Ocean population being the longest (189 ± 12.3mm) and Lake Michigan population the shortest (122 ± 0.3 mm). Mean thiamine concentrations (nmol/g ± standard error) for single-year samples for Lake Huron, Lake Michigan, and Little Clear Pond (New York) were 9.9 ± 0.8, 3.9 ± 0.7, and 8.1 ± 2.3 nmol/g, respectively. Thiamine concentrations for multiple-year samples ranged from 1.1 to 15.6 for Lake Ontario, from 2.6 to 3.3 for Lake Erie, from 5.0 to 9.9 for Lake Superior, and from 10.9 to 13.3 for the Atlantic Ocean (Fore River). Although highly variable within populations and across years, thiamine concentrations in most spawning adults appeared to be adequate in all the waters for the years sampled except for 2006 and 2009 in Lake Ontario and 2009 in Lake Erie. [ABSTRACT FROM AUTHOR]

Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11-ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11-h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 109 and 15.5 × 109 spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii. [ABSTRACT FROM AUTHOR]