Vergleichende Untersuchungen an zwei Loriarten (Trichoglossus goldiei bzw. Trichoglossus haematodus haematodus) zur Futter- und Wasseraufnahme sowie zur Nährstoffverdaulichkeit und zur Zusammensetzung der Exkremente bei Einsatz verschiedener Einzel- und Mischfuttermittel

The intention of this study was primarily to get basic data about the nutrition of lories (feed composition, feed and water intake, digestibility). An additional point of interest was the influence of the consistency of the given food (dry, mushy, liquid), or rather the adding of fibre, on the quality of the excrements. Methods: Six Goldie’s lorikeets and six rainbow lorikeets (Trichoglossus goldiei - TG; Trichoglossus haematodus haematodus - THH) were used for the study (TG: O BM: 40 - 50 g; 1 - 4 years old; THH: O BM: 120 - 140 g; 1 - 12 years old). In two succeeding trial periods (A/B) a total amount of six different sorts of feed was offered. During Period A, the birds only got one of the three most often used feeds („Lory soup“, apples or pollen). In Period B different mixtures (n=3) were fed, which were based on the “Lory soup” (used in Period A) with the addition of different types of fibre (apple fibre, oat bran, dried carrots). During the trial period, which preceded an adaptation period (duration: 5 d) the lories were kept separately in metabolism cages. In this time the lories were fed ad libitum each day with a precisely weighed amount of feed and water at 8 am (an additional feeding took place at 2 pm when mushy mixtures were offered). The offered feed and feed refusals were weighed and collected in the same way as the excrements. At the beginning as well as at the end of each trial period, the body weights of the lories were determined (weighing time: 8 am, before feeding). Apart from that the rhythm of the feed intake as well as the time needed for ingestion of one gram dry matter were determined. The analyses of the collected samples (feed supply, feed refusals, excrements) were carried out using the following methods: crude nutrient contents by Weender Analysis, starch/ sugar by using enzymatic test kits, macro/ trace minerals by atomic absorption spectroscopy. Digestibility of organic matter as well as of crude protein were corrected by the uric acid content of the excrements (Nurinary = Nuric acidx 1.2). Results: Feed- and Water Intake Behaviour 1.      Independent from the offered feed and the observed species the lories showed no increased feed intake at any time of the day. 2.      The time spent for food consumption (time per g DM), when offered “Lory soup” (5 [TG] respectively 2 min/g DM [THH]) clearly remained under the time when other feeds were offered. In comparison to the “Lory soup” the birds needed the tenfold amount of time for consumption when apples or pollen were fed. 3.      The dry matter intake varied between 13 and 15 (TG) respectively 8 and 10 (THH) g DM/100 g BM/d (Period A). However, this amount increased by 50 - 70 %, when a crude fibre source was added to the “Lory soup” (Period B). 4.      When provided with pollen (DM: ~ 87 %), the lories‘ water intake was 2½ times higher than their consumed amount of dry matter. In contrast to that, almost no additional water was taken in when feed with a high moisture content (mushy feed, apples) was offered. Food digestibility 1.      Both species achieved an apparent digestibility of organic matter (ADOM) of more than 90 % (apples), approximately 82 % (“Lory soup”) and around 55 % (pollen). 2.      A comparison of DM-digestibility values of all provided mushy feeds showed that any supplementation of fibre had no effect on the birds’ digestibility. Energy- and nutrient supply 1.      A daily energy intake of » 860 (TG) respectively » 650 (THH) kJ ME/kg KM0.75 led to a constant body mass. 2.      Since the lorikeets reacted with an increased feed intake a raise of crude fiber content of the diet did not result in a reduced energy intake. 3.      From the regression equation the maintenance nitrogen requirement of both species were calculated (2.3 [TG] respectively 2.1 [THH] g XP/kg BM0.75). Quality of excrements 1.      The moisture content of the offered feed had a decisive influence on the dry matter content of the excrements, that reached 8 % after the intake of “Lory soup”, approx. 2 % when offering apples and around 30 % when providing dry pollen. Conclusion: The energy requirement for maintenance of the lories examined in this study (TG: 861 kJ ME/kg BM0.75; THH: 650 kJ ME/kg BM0.75) corresponds more or less to the energy requirement for maintenance of granivore parrots with approx. the same body mass. The digestibility of organic matter of pollen is rather low. However, it contains protein and different kinds of sugar which can be digested relatively well (ADXP» 55 %, ADsugar > 90 %). In order to assess the content of metabolizable energy of pollen a formula for estimation adapted to the pollens’ characteristics has to be used. The use of crude fibre supplemented diets in order to create a “reduction diet” seems to be ineffective because lories react to a decreasing level of energy density in feed by increasing their dry matter intake. Maintenance requirements of protein in lories is lower than in granivore psittacine birds. This could be related to the fact that the food (nectar, fruits) in their original environments is low in protein. In order to fulfil the birds‘ protein requirements for maintenance, a protein content between 3 - 4 (TG) respectively 3.5 - 4.5 (THH) percent of dry matter should be sufficient. The current use of feed mixtures with a crude protein content of approx. 15 - 20 % leads to an excessive protein intake that has to be regarded critically due to the strong use of excretory mechanisms. Apparently, a positive change of excrement quality is only possible by reducing the moisture content of the provided food (e.g. use of pellets) respectively by adding oat bran to the diet.