Submitted to: Journal of Aquatic Food Product Technology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/26/2008
Publication Date: 6/20/2008
Citation: Plante, S., Smiley, S., Oliveira, A., Stone, D., Hardy, R.W., Bechtel, P.J. 2008. Chemical Characterizations of Testes Meals Made from Alaska's Seafood Processing Byproducts. Journal of Aquatic Food Product Technology. 17(2):195-211. DOI: 10.1080/10498850801937265. Interpretive Summary: In Alaska, salmon are only harvested in summer, during their spawning migration. Consequently, harvested salmon always possess mature gonads. Pollock, on the other hand, is harvested several times during the year, but gonad maturation peaks only in late winter. This study opens up an interesting new opportunity for the use of meals made from Alaskan fish testes. We have demonstrated that a high quality meal can be produced from this material. Considering the fact that regular fishmeals are relatively low in nucleotides, the high concentrations of purines (and by implication pyrimidines as well) that are found in fish testes make it an ideal choice to act as a potential immune system stimulant when incorporated into aquaculture feed formulations. Salmon testes meal was higher in purine concentrations and may be a good choice for maximizing stimulation to the immune system of fish, but overall, pollock testes meals have better nutritional qualities (better amino acid profile, more and higher lipid quality, higher in phospholipids) and may be a more complete dietary ingredient.
Technical Abstract: Our objective was to produce a unique feed ingredient from underutilized walleye pollock (Theragra chalcogramma) and pink salmon (Oncorhynchus gorbuscha) testes. Protein contents in meals from both species were above the values found in high quality herring meals, but both were poor in some essential amino acids; however, both were good sources of the amino acid taurine. Pollock meal was very rich in phospholipids and essential polyunsaturated fatty acids, indicating a potential role as a larval starter feed ingredient. Purine contents in both pollock and salmon testes meals were very high when compared to other fish byproducts or commercial fishmeals. The high concentrations of purines found fish testes make it also an ideal dietary supplement candidate to act as an immune system stimulant. In summary, the salmon meal was high in purines, but overall, the pollock meal had better nutritional qualities.