Effect of dilution degree of articifial nectar food and supplemental provision of fruit on nutrient and energy intake in Rainbow lorikeets.

Abstract

Objectives: Captive-kept lorikeets are usually fed dilutions of commercially available powdered nectar as principal nutrition. These powdered foods have to be diluted before use and degree of dilution might be determining for overall nutrient and energy intake. The present trial was aimed to study the effect of degree of dilution of artificial nectar and availability of supplemental fruit on intake in two lorikeet subspecies. Materials and Methods: Six green-naped lorikeets (Thrichoglossus h haematodus) and six red-breasted lorikeets (Trichoglossus h mitchellii) were fed three different dilutions of nectar during three consecutive 14-d periods. Half of the birds received also pieces of apple. Daily food intake was measured after 7-day adaptation periods, on which nutrient intake was calculated. Results: Both degree of dilution of nectar and supplementation with apple significantly influenced nutrient intake; moreover, effects depended on subspecies. When provided the highly diluted nectar compared to the low dilution, red-breasted lorikeets increased as-fed intake (+46%), which was sufficient to maintain similar dry matter intake (only -3%) and thus energy and protein intake. Green-naped lorikeets, however, did not fully compensate higher diluted nectar by increased as-fed intake (+32%), resulting in a 13% lower dry matter intake. Next, nectar intake decreased when apple was available and apple intake increased when fed higher diluted nectar. Conclusions: Present data clearly demonstrate that dilution degree of nectar and provision of additional food items, in this case apple, must be considered carefully, reckoning with differences in subspecies, in order to modulate voluntary nutrient intake in lorikeets