	Contents Foreword \ Acknowledgements LIST of TABLES LIST of FIGURES
1	Trees -- components of farming systems	1

1.1	Introduction	1
1.2	Feed resources avaible for ruminant production in developing countries	3
1.3	Overview: the potential uses of tree foliages	3
1.4	Trees foliage as ruminat feeds -- perspectives and properties	4
1.5	Trees in agricultural ecosystem	5
1.6	Tree foliage as basal feed or as supplements to other foliages	6

2	Background nutrition digestive physiology and metabolism of ruminants	8

2.1	Introduction	8
2.2	Forage / feed resource in developing countries	10
2.3	Animal productivity from forage resource in the tropics	11
	2.3.1 Effects of hight heat load on animal production	11
2.4	Improving ruminant production on low digestibility forages	14
2.5	Rumen digestive physiology	14
2.6	Microbial growth in the rumen	15
	2.6.1 Requirements for animo acids by rumen microbes	15
	2.6.2 Inefficiences microbial growth	16
	2.6.3 Inefficency, microbial growth and heat generation in the rumen	16
2.7	The effects of specific nutrient deficiences on rumen microbes	19
	2.7.1 Recent studies on the effects of ammonia levels on digestibility of forage and microbial efficiency in the rumen	20
2.8	Overview of microbial growth efficiency	22
	2.8.1 Strategies to alter P/E ratio in the nutrients absorbed by ruminants	22
	2.8.2 Manipulating P/E ratios using bypass protein supplements	24
2.9	Feeding standars -are they applicable to forage diets?	24
2.10	Role of fodder trees in the nutrition of ruminants	26

3	Balancìng nutrition te maximize forage utilization	28

3.1	Concepts of balanced nutrition	28
3.2	Meeting nutritional requierements of ruminants with appropiate supplements	29
3.3	Supplying the rumen microbies with ammonia	30
3.4	Some examples of the value of ruminants in cattle given forage based diets	30
	3.4.1 Effects of supplementation with urea/molasses/multinutrient blocks (MUMB) on cattle production	31
	3.4.2 Effects of multinutrient mixes on growth rates and milk yield of cattle	32
	3.4.3 Effects of MUMB on reproduction af cattle, sheep and goats	34
	3.4.4 Conclusion on reproductive efficency	36
3.5	Conclusion on the use of supplements of that provide critically deficent nutrient	36
3.6	Crude protein requirement of ruminants	37
3.7	Application of the new feeding strategies based on balancing nutrients	38
	3.7.1 Major application of balanced nutrition in developing animal production system	39
3.8	Avaibility of by pass protein meals	40
3.9	Identification of by pass protein source	41


4	Potential roles of trees fodders in ruminant nutrition	44

4.1	Introduction	44

4.2	Anti - nutritional and nutritionally beneficial aspects of tannins in forage	45
4.3	Effecta of tannins on rumen function	47
4.4	Tannin in plant foliage	48
4.5	Tannin mobilization	48
4.6	The implications of tannin build - up in foliage	49
4.7	Tannins in the rumen	50
4.8	Other secondary plant compounds in fodder trees	52
4.9	Comparisons of trees foliage and multinutrient blocks as supplements to ruminants fed poor quality feeds	53
4.10	Trees foliage as supplements to pasture or other low quality forages	54
4.11	Improvement in productivity of cattle from supplementation with tree foliage	60
4.12	Responses of cattle to supplementation of forage based diets with tree foliage	60
4.13	Evidence for tree foliages as sources of rumen ammonia and minerals	63
4.14	Foliage of fodder trees and mineral supplements	64
4.15	Tree foliage as potential sources of by pass proteins	65
4.16	Nutritional ecology of ruminants	68
4.17	Overall	70
4.18	Conclusions on the use of trees as fodder ruminants	70

5	Bypass proteins from tree foliages	72

5.1	Introduction	72
5.2	Natural protection of leaf proteins	73
5.3	Effects of drying fodder tree foliage	76
5.4	Effects of adding chemicals	78
5.5	Tree foliages as supplements or as basal diets	79
5.6	High density forage production from Leucaena	80
5.7	Assaying the nutritional value of protein in leaf foliages or meals	82
5.8	Conclusion	85
5.9	Postscript	86

6	Bibliography	87