Influence of egg vitamin A status and egg incubation temperature on subsequent development of the early vertebral column in Atlantic salmon fry
Abstract:The effect of egg vitamin A (VA) status and egg incubation temperature on the development of spinal disorders was investigated in Atlantic salmon Salmo salar fry. Atlantic salmon eggs were sorted into two groups with high VA (3·3 ± 0·1 g retinol g−1 dry mass) and low VA (2·2 ± 0·3 g retinol g−1 dry mass) status before fertilization and incubated at high (14° C) or low (8° C) temperature from 133 day degrees until the onset of feeding. High egg incubation temperatures increased the concentration of retinol in the eggs: the high VA and high temperature group displayed a significantly higher retinol concentration than the high VA and low temperature group (P = 0·001). After hatching, all experimental groups increased their retinol concentration. The source of the increased retinol levels was probably retinal, although astaxanthin may also be a VA precursor after hatching. Atlantic salmon fry incubated at high temperatures had increased amounts of notochord tissue. When measuring morphogenic activity in the notochord using the expression of sonic hedgehog (shh, mRNA), however, no significant difference was found between the experimental groups. No clear effect of VA status or incubation temperature could be found on the formation of the early vertebral column although Atlantic salmon fry incubated at low temperatures had less regular constrictions of the prospective vertebral column than fry incubated at high temperatures.
Document Type: Regular Paper
Affiliations: 1: Institute of Marine Research, P. O. Box 1870 Nordnes, 5817 Bergen, Norway and 2: Department of Fisheries and Marine Biology, University of Bergen, P. O. Box 7800, 5020 Bergen, Norway 3: National Institute of Nutrition and Seafood Research, Strandgt. 229, P. O. Box 176 Sentrum, N-5804 Bergen, Norway,
Publication date: 2004-02-01