Passeriformes (perching and songbirds) is the largest order of birds. Birds from this order adopt as many different feeding strategies as the variety of ecosystems they inhabit. They may be granivorous, frugivorous, insectivorous, nectarivorous, omnivorous and even carnivorous. Most passeriformes kept in captivity (finches and canaries) are granivorous, with a natural diet that consists of the seeds of cultivated grasses and legumes. On occasion, the diet is supplemented with berries, the green parts of plants, as well as insects and grubs. Commercial seed mixes may not contain the variety of seeds necessary to meet the nutrient needs of the animals that eat them; it is why we recommend supplementing a seed-based diet with fresh fruits and vegetables (leafy greens, sweet potato, carrot, berries, etc.), as well as with a formulated diet such as Lafeber™ or Harrison's™ pellets (chose the smallest size of pellet available). The latter have the advantage of being well balanced and preventing sorting, unlike seed mixes. For laying hens, calcium supplementation is necessary, and can be provided by adding a supplement of crushed oyster shell or cuddle bone to the diet.
As with all birds, special considerations are often necessary during demanding situations such as reproduction, illness, or competition. These should be addressed with your avian veterinarian. Finally, all diet changes need to be performed gradually, and the weight of the bird monitored closely to ensure that it is being maintained.
Édouard Maccolini, DVM, IPSAV (Zoological Medicine)
Julie Hébert, DVM, Dipl ABVP (avian practice)