Fatty acid profiles of crop contents of free-living psittacine nestlings and of commercial hand-feeding formulas.

Research on psittacine nutrition is limited, and nestling requirements are poorly understood. This study analysed fatty acid (FA) profiles of crop contents of free-living scarlet macaws (Ara macao, n = 18), red-and-green macaws (Ara chloropterus, n = 5), Cuban parrots (Amazona leucocephala bahamensis, n = 27), lilac-crowned Amazons (Amazona finschi, n = 33) and thick-billed parrots (Rhynchopsitta pachyrhyncha, n = 32). The same analysis was carried out on 15 commercial parrot hand-feeding formulas. The mean FA concentration of the crop samples of each species ranged from 15% to 53% DM for crop samples and ranged from 6% to 22% for hand-feeding formulas. Long-chain FA represented over 92% of all FA in the crop samples and over 81% of all FA in the commercial formulas. Parrot species shared similarities in saturation profiles of crop samples, ranging between 13%-29% saturated fatty acids (SFA), 12%-40% monounsaturated fatty acids (MUFA) and 39%-58% polyunsaturated fatty acids (PUFA). All studied psittacines, except for the red-and-green macaw, were within the range of values for hand-rearing formulas. Palmitic acid was the most common SFA in scarlet macaws, red-and-green macaws, Cuban parrot, thick-billed parrot and in all but one commercial formula. Palmitic and stearic acids dominated the SFA in the samples of the Lilac-crowned Amazon. Oleic acid was the most common MUFA in all hand-feeding formulas as well as in the crop samples, except for the lilac-crowned amazon and the thick-billed parrot where vaccenic acid dominated. Linoleic acid was by far the most common PUFA found in the crop samples as well as in the hand-feeding formulas. PUFA were largely dominated by the n6 family, both in the crop samples and the formulas. The data presented on nestling diets of free-living parrot species provide a foundation for future researchers to test whether increasing FA concentration in hand-feeding formulas improves nestling development or if species-specific formulas will be advantageous.