Abstract

CUENCA SORIA, Carlos Alberto et al. In vitro PH-STAT digestibility of protein ingredients in the mayan cichlid Cichlasoma urophthalmus. Universidad y ciencia [online]. 2013, vol.29, n.3, pp.263-275. ISSN 0186-2979.

The commercial culture of Cichlasoma urophthalmus has not been developed, because there is not any commercial balanced food available with the ingredients required for the species. This study determined the degree of hydrolysis (GH,%) of 29 animal and plant protein ingredients using the pH STAT system, and calculated the total free amino acid content (ALT, µg ml^-1) using multienzymatic extracts obtained from the stomach and intestine of C. urophthalmus juveniles. Of all the tested ingredients, the optimum acid/alkaline GH values were those of the poultry-by products and meat (9.6 ± 1.8 / 22.7 ± 4.3), pork meal (22.0 ± 0.52/31.6 ± 2.2) and coconut paste (10.4 ± 1.5/21.6 ± 5.2), and they were significantly greater (p < 0.05) than the acid/alkaline GH values of the reference ingredients hemoglobin/casein (6.9 ± 1.8 / 2.2 ± 0.5). Concurrently, the acid/alkaline ALT values for these same ingredients were statistically equal (p > 0.05) (793.9 ± 21.1/1587.8 ±13.0, 310.5 ±33.0/1013.2 ± 20.3, 591.9 ± 4.1/574.6 ± 11.9 respectively) to those of the acid/alkaline reference ingredients (hemoglobin 1293.1 ± 24.1 and ± casein 943.3 ± 14.7). It is concluded that the test ingredients may constitute strong sources of proteins, as the base of a standard formula for C. urophthalmus culture.

Keywords : Aquaculture; native cichlid; meal; nutrition.