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In vitro digestibility of different prey species of minke whales (Balaenoptera acutorostrata)

Published online by Cambridge University Press:  09 March 2007

Erling S. Nordøy
Affiliation:
Department of Arctic Biology and Institute of Medical Biology, University of Tromsø, Tromsø, Norway
Wenche Sørmo
Affiliation:
Department of Arctic Biology and Institute of Medical Biology, University of Tromsø, Tromsø, Norway
Arnoldus Schytte Blix
Affiliation:
Department of Arctic Biology and Institute of Medical Biology, University of Tromsø, Tromsø, Norway
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Abstract

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Information on diet composition, daily energy expenditure, energy storage and the utilization of energy in the prey are important factors when evaluating the food consumption of minke whales (Balaenoptera acutorostrata) during their summer stay in northern waters. The purpose of the present study was in this context to obtain information on the digestible energy (DE) of different prey selected by minke whales. An in vitro three-stage digestion technique, simulating the different compartments of the digestive system, has been developed. The initial step simulated the anaerobic microbial fermentation of substrate in the fortestomach. The next stage included the addition of pepsin (EC 3.4.23.1)–HCI, simulating ventricle enzymic decomposition, and finally, in the third step, fresh extract from duodenal contents was used to simulate enzymic intestinal degradation of the remaining components of the food. The inoculum was normally obtained from animals which had recently eaten the prey to be tested. In such tests we obtained a dry matter disappearance (DMD) and a DE for herring (Clupea harengus) of 80·4 (SD 5·0)% (n 18) and 92·1 (SD 3·7) % (n 16) respectively, and a DMD of krill (Thysanoessa sp.) of 83·4 (SD 4·9)% (n 6). The DMD of krill was reduced to 73·8 (SD 7·3)% (n 8) while the DE was 70·6 (SD 10·4) % (n 7) when inoculum from whales which had recently eaten cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) was used. These results indicate a high digestibility of the most common species of prey in these animals, and also that the whales have little difficulty in changing from one prey species to another.

Type
Digestibilty of Prey by Minke Whales
Copyright
Copyright © The Nutrition Society 1993

References

REFERENCES

Folkow, L. P. & Blix, A. S. (1992). Metabolic rates of minke whales (Balaenoptera acutorostraia) in cold water. Acta Physiologica Scandinavica 146, 141150.CrossRefGoogle ScholarPubMed
Furaya, S., Sakamoto, K. & Takahashi, S. (1979). A new in vitro method for the estimation of digestibility using the intestinal fluid of the pig. British Journal of Nutrition 41, 511520.CrossRefGoogle Scholar
Graham, H., Lswgren, W. & Aman, P. (1989). An in vitro method for studying digestion in the pig. 2. Comparison with in vivo ileal and faecal digestibilities. British Journal of Nutrition 61, 689698.CrossRefGoogle Scholar
Herwig, R. P. & Staley, J. T. (1986). Anaerobic bacteria from the digestive tract of North Atlantic fin whales (Balaenoptera physalus). FEMS Microbiology, Ecology 38, 361371.CrossRefGoogle Scholar
Herwig, R. P., Staley, J. T., Nerini, M. K. & Braham, H. W. (1984). Baleen whales: preliminary evidence for forestomach microbial fermentation. Applied and Environmental Microbiology 41, 421423.CrossRefGoogle Scholar
Keiver, K. M., Ronald, K. & Beamish, F. W. H (1984). Metabolizable energy requirements for maintenance and faecal and urinary losses of juvenile harp seals (Phoca groenlandica). Canadian Journal of Zoology 62, 769776.CrossRefGoogle Scholar
Løwgren, W., Graham, H. & Åman, P. (1989). An in vitro method for studying digestion in the pig. 1. Simulating digestion in the different compartments of the intestine. British Journal of Nutrition 61, 673687.CrossRefGoogle Scholar
Mathiesen, S. D., Aagnes, T. & Sørmo, W. (1990). Microbial symbiotic digestion in minke whales (Balaenoptera acutorostrata). Paper SC/42/NHMi9 presented to the IWC Scientific Committee, 1990.Google Scholar
Nordøy, E. S. & Blix, A. S. (1992). Diet composition of northeastern Atlantic minke whales. Reports of the International Whaling Commission 42, 393398.Google Scholar
Øien, N. (1991). Abundance of the northeastern Atlantic stock of minke whales based on shipboard surveys conducted in July 1989. Reports of the International Whaling Commission 41, 433437.Google Scholar
Olsen, M. A., Nordsy, E. S., Blix, A. S. & Mathiesen, S. D. (1993). Functional anatomy of the gastro-intestinal system of northeasten Atlantic minke whales (Balaenoptra acutorostrata). Journal of Zoology (In the Press).Google Scholar
Parsons, J. L. (1977). Metabolic studies on ringed seal (Phoca hispida). MSc Thesis, University of Guelph.Google Scholar
Ronald, K., Keiver, K. M., Beamish, F. W. H & Frank, R. (1984). Energy requirements for maintenance and faecal and urinary losses of the grey seal (Halichoerus grypus). Canadian Journal of Zoology 62, 11011105.CrossRefGoogle Scholar
Schweder, T., Øien, N. & Hsst, G. (1991). Estimates of the detection probability for shipboard surveys of northeastern Atlantic minke whales, based on a parallel ship experiment. Reports of the Iniernaiional Whaling Commission 41, 417432.Google Scholar
Tilley, J. M. A & Terry, R. A. (1963). A two-stage technique for the in vitro digestion of forage crops. Journal of the British Grassland Society 18, 104111.CrossRefGoogle Scholar