Studies on the Nutrition of Macropodine Marsupials. 1. Intake and Digestion of Lucerne Hay and Fresh Grass, Phalaris Aquatica.

Abstract

Intake and digestion of chopped lucerne hay was studied in three macropodine species, eastern grey kangaroo Macropus giganteus. red-necked pademelon Thylogale thetis and tammar wallaby M. eugenii, and in sheep. The utilization of fresh Phalaris grass by the two wallaby species T. thetis and M. eugenii was also examined and compared. On the chopped lucerne hay diet, intake of organic matter (OM) was similar in sheep and M. giganteus, but sheep digested more (P<0.05) OM and thus consumed more (P<0.05) digestible energy (DE) than all three macropodine species. Among the macropodines. M. eugenii consumed the least (P<0.01) OM and DE but digested more (P<0.05) OM. However, acid detergent fibre (ADF) digestibility was similar in the three macropodine species and lower (P<0.05) than in sheep. On the fresh grass diet M. eugenii consumed less (P<0.05) OM and DE than T. thetis. ADF digestibility was similar in both species. Although ,M. eugenii consumed less nitrogen (N) than the other three species on the lucerne diet (P<0.01) and less N than T. thetis on the Phalaris diet (P<0.05), N balance was similar and positive in all species. Data from this and other published studies indicate that the maintenance requirements for energy and nitrogen of most macropodines are lower than for sheep, and appear to be lower in M, eugenii than in any other macropodine studied so far. It is also apparent that there are probably few real differences among the Macropodinae in efficiency of fibre digestion, at least on diets of adequate nitrogen and DE content.