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The overall aim of this thesis was to get information about the utilisation of local foliages used for feeding in smallholder farms, the nutritive value, feed intake, digestibility and nitrogen retention when feeding some of these local foliages and the selective behaviour when feeding the foliages to local growing goats. The foliages were from Erythrina (Erythrina variegata), Fig (Ficus racemosa), Jackfruit (Artocarpus heterophyllus), Jujube (Ziziphus jujuba Mill), Kapok (Ceiba pentandra) and Mango (Mangifera indica) and were collected in five villages in Xaythanee District. The experiments were carried out in the Livestock and Fisheries Department, Faculty of Agriculture, National University of Laos, Vientiane City, Lao PDR.
Sixty farmers were interviewed using formal and informal interviews to collect information on the agriculture and livestock situation. Traditional management and extensive systems were generally used for livestock in this area, particularly for ruminants. Diseases and lack of feed or theft were the main constraints or problems for ruminants, especially for goat production. Fifteen forage species were recorded as available to goats, mostly from fruit trees such as Jackfruit, Jujube and Tamarind. No feed supplementation was used in the free grazing system, although some forages were cut and carried after kidding and presented in the fresh form. Only very few forage species were used by the farmers.
The dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), condensed tannins (CT) and water extractable dry matter (WEDM) of the collected local foliage species were estimated. Twelve local male goats of 14.6 kg initial body weight (BW) and 3.5 months of age were used in an experiment, to evaluate the effect of the six different foliage species on intake, digestibility and nitrogen retention. The goats were offered the foliage ad libitum (130% of the mean daily feed intake). Low content of CP and high DM content were found in the leaves plus petioles of Mango foliage, while a high nutritive value, especially CP content, and a low content of DM and CT was found in Erythrina. Fig, Jujube and Mango foliages were significantly lower in DM intake, apparent digestibility and N retention (P<0.05), compared to Erythrina, Jackfruit and Kapok foliage. The WEDM was not a good predictor of DM digestibility, but it could be used to predict N retention. Four local male goats with an initial weight of 13.4 kg and around 6 months of age were used in 4*4 Latin Square design to investigate the effect of supplementing Water spinach (Ipomoea aquatica) to the low quality foliages. The four diets were: Water spinach ad libitum or Fig, Jujube or Mango ad libitum + 0.5% of BW as DM Water spinach. The results showed that Water spinach had a higher CP content but lower DM content than the other foliages. Water spinach alone had significantly higher CP digestibility (P<0.05), but lower feed intake and N retention, compared to the other diets. Water spinach could be used as a protein source and increase DM and CP intake, apparent digestibility and N retention when complemented with Fig, Jujube or Mango foliage, in comparison to feeding these foliages alone.
Feed intake and selective behaviour of eight local male goats (15.7 kg and 7 months of age) were studied by following each goat during 9 hours with the six foliages available. Three types of foliage species: Erythrina, Jackfruit and Kapok foliage, were selected more often and more time was spent eating these foliages, resulting in higher total feed intake compared to Fig, Jujube and Mango foliage, but the Jujube foliage was preferred by some of the goats. The goats were very individual in their selective and intake behaviour.
The utilisation of foliage species from fodder trees or fruit trees can be increased, with improved performance and better profits, but the farmers need to have better knowledge about the use of foliages.
Key words: Free grazing systems, Foliage, Goats, Feed intake, digestibility, N retention, Erythrina, Fig, Jackfruit, Jujube, Kapok, Mango, Water spinach, Selective behaviour