Many methods have been utilised to determine the nutritional requirements of crustaceans; factorial models have an important role in defining these. Proteins and amino acids (AA) are a large, costly component of feeds. The crude protein (CP) requirement for some lobster species is currently >50%. A greater understanding of AA requirements allows the production of more efficient feeds potentially optimising the CP requirements, therefore considering protein as AA requirements is necessary. There are no commercial formulated feeds for the spiny lobster Panulirus ornatus, and determining AA requirements is critical to overcoming the feed barrier to economically sustainable tropical rock lobster aquaculture.
A feeding trial focussing on nutrient intake, digestibility, growth and chemical composition, was undertaken to determine the CP and AA requirements. The experiment was conducted using isoenergetic feeds with six graded CP inclusions ranging from 42 to 64%. This enabled a preliminary factorial model to be produced aiding in the production of P. ornatus feeds with known growth potentials. Incorporating the ideal protein concept allowed for estimations of maintenance and growth requirements for individual AAs as the animal grows. This provides a baseline for future investigations into the AA requirements of lobsters.