Nguyen Kim Lin et al., 2003. Livest. Res. Rural Dev. 15 (6) article #41

Two experiments were carried out to study effects of tree foliages versus grasses on intestinal nematode infestation and growth of confined goats. In experiment 1, 20 males and 10 females of Bachthao and cross-bred (Bachthao x Barbari) goats (initial live-weight from 9 to 14 kg) were allocated to 5 sources of forage which were offered as supplements to rice bran (RB) and a  Molasses Urea Block (MUB). The forages were: fresh foliage of cassava (Manihot esculenta), Jack Fruit (Artocarpus heterophyllus) and Leucaena (Leucaena leucocephala) and fresh grasses of Guinea (Panicum liconi) and Ruzi (Brachiaria ruziensi). The goats were confined in pairs in wooden pens of 1.2 x 1.4m area on a raised slatted floor. They were fed the experimental diets for 10 days and de-wormed before starting the experiment. The feed offered was adjusted at 14 day intervals according to live weights. The experiment began on 11 December 2001 and continued until 11 April, 2002.The forages were harvested daily from the fields in the Goat and Rabbit Research Center (GRRC). The foliage from cassava (C) and Leucaena (L) were harvested after approximately 2 months re-growth by cutting at 30 cm (C) and 70 cm (L) above soil level. The foliage from Jack fruit (trees were older than 5 years) was harvested after 3 months re-growth by cutting at 150 cm and higher above soil level. The Guinea and Ruzi grasses were harvested after 4 weeks and 7 weeks re-growth by cutting at 3 to 5 cm above soil level. All the foliages were fed at ad libitum. Rice bran was given at 10 g/kg live weight and a molasses-urea-block at 5 g/kg live weight. In experiment 2, 24 male goats recently weaned, with initial live-weight from 9 to 12 kg, were allocated to 4 treatments in a 2*2 factorial arrangement: Guinea versus Ruzi grass and two cutting heights of each grass (3 to 5 cm and 10 to 12 cm above soil level). The Guinea and Ruzi grasses were cut after 4 weeks and 7 weeks re-growth at between 9 am and 5 pm. The grasses were fed ad libitum. Rice bran was given at 15 g (DM)/kg live weight. In both experiments, records were kept of feed intake (daily) and live weight (15 day intervals). Faeces samples were taken at the beginning and monthly to determine eggs of Strongyle and coccidian oocyts. The goats  grew faster and had lower levels of infestation with nematode parasites when fed: tree foliages rather than  grasses (Experiment 1); or grass cut at 10 to 12cm rather than 3 to 5cm, above soil level (Experiment 2). It is concluded that  there are two mechanisms which favour the use of tree and shrub foliages in diets for goats: the presence of condensed tannins in the leaves and the physical attributes of such plant species which do not facilitate the migratory habits of infective nematode larvae.