Potential Roles of Tree leaves in Ruminant Nutrition
Post no 1375 Dt 26th August 2019
Compiled & shared by- DR RAJESH KUMAR SINGH, JAMSHEDPUR,9431309542,rajeshsinghvet@gmail.com.
Introduction:
Large varieties of plant materials which are conventionally not included in the feeds for livestock are used for feeding of cattle and other ruminants during periods of scarcity. Some varieties of tree leaves are conventional feeds for sheep and goats. Certain varieties are also fed to cattle and buffaloes. Leaves of different species have different nutritional characteristics. In general, in the early stages of growth the leaves contain fairly high percentage of crude protein and comparatively low fibre content. As the vegetation advances in age, there is progressive decrease in the protein content and increase in the crude fibre. Tree leaves are generally rich in calcium, but have low phosphorus. The ratio of calcium and phosphorus is generally wide. Due to presence of tannic acid, the digestibility of protein in the leaves is low.
A major constraint to livestock production in the tropics is the seasonal fluctuation in forage yield and quality from grasses. There is usually adequate forage of fair to good nutritive value in the wet season, but in the dry season available forage from natural pastures are usually inadequate both in terms of quality and quantity to meet even the maintenance requirements of livestock.Trees and shrubs have been shown to be capable of providing high quality fodder in the dry season.The role of fodder trees and shrubs in the diet of animals is considered particularly important in countries like India where small land holdings and large ruminant densities result in an especially severe problem of feed availability. Generally these leaves areused for feeding sheep and goat and sometimes to cattle during periods of fodder crisis.
Nutritive Values of Tree leaves ———–
Generally, the dry matter content of the various tree leaves varies from 20 to 40%, with 10-15% crude protein on a DM basis (Singh., 1982). Subabul has higher values of 20 – 23%.Ether extract (EE) fraction is also fairly high compared with grasses and hays. Contain comparatively low percentage of crude fibre compared with grasses and hays. Youngertree leaves before floweringhave more protein contents than mature leaves after flowering. The crude protein content decreases and the crude fibre content increases with increasing age of tree leaves (Singh., 1981). Their fibre is complex and highly lignified at maturity. Palatability, digestibility, and nutritive value of tree leaves decreases as the leaves advance in maturity. The tree leaves contain 8– 33 % CP, 1–19 % EE , 11–50 %CF , 0.2–3.0 % Ca and 0.1–0.3 % P. The digestibility coefficient of dry matter, crude protein, crude fibre, ether extract and nitrogen free extract in tree leaves ranged from 40–75, 28–83, 24–82, 32–65 and 51–85 %, respectively(Rai et.al. 2007).Calcium content of tree leaves is 2-3 times more than that of cultivated fodders or grasses. The phosphorus content is, in general, low, resulting in a wide calcium to phosphorus ratio. • Tree fodders are richin protein and mineral contents as compared to grasses and thus can be supplemented to low quality grasses (Aganga et al., 2003). • Plants take up mineral readily during early growth, but as growth accelerates, dry matter accumulates more rapidly than minerals, contents of most minerals therefore fall with advancing maturity (Jones and Wilson., 1987). • Leucaena spp; G. sepium and Acacia spp. – fix atmospheric nitrogen – now an important component in the farming system in many countries in the tropics. • Ruminants are mostly fed on low quality roughages – addition of tree leaves toruminant diets improve the utilization of low quality roughages mainly through supply of nitrogen to rumen microbes. Tree fodders are important source of nutrients for small ruminants. Goats prefer to browse on small bushes rather than grazing but due to the limitation of bushes tree leaves form a major part of their diet.Most of tree leaves are rich in crude protein and TDN contents which can meet the requirements of goats. Ailunthus excelsa, morus alba can even fully satisfy the maintenance requirement of goats and sheep, respectively. The leaves of Ficus bengalensis are consumed in greater quantitiesby goats.
Deleterious principles———-
Presence of Anti nutritional factors like mimosine in Leucaena leucocephala, triterpinoid derivatives (azadirachtin, nimbidin) in Azadirachta indica and phenolics in most of the leaves limit their use as animal fodder.The presence of tannins adversely affect the dry matter digestibility and use of nutrients, and an inverse relationship exists between tannin content and crude protein digestibility (Lohan et al. 1980). Because of their inhibition of proteolytic and cellulolytic enzyme, protein utilization is affected by inclusion of leaves (Silanikove et al 2001); however, the inclusion of a limited quantity of tree leaves in animal feed is recommended to improve rumen function and productivity (Osakwe et al 2004).Level of tannins are higher in the early stages of growth (Negi,1977). Restricting the level of feeding to more available in lower gut. Some trace minerals, such as fluorine, molybdenum, and selenium, are reported to be present in toxic amounts in some tree leaves (Gupta et al. 1982).
Kinds of leaves that can act as potential feed:
Mulberry leaves (Morus indica)
Mulberry leaves have an appreciable potential as protein source in small ruminants feeding, thus leaves of mulberry can also be used as main feed for small ruminants (Kandylis et al., 2008).It contain 23.5% and 18.2% CP with 12.8% and 23.1% ash contents at young and mature stages of growth, respectively (Malik and Chughtai, 1979).DCP content is 7.8% and TDN is 48.4 % in them.The biomass yield of fresh leaves is around 15 to 22 tonnes/ha/year.
Pipal leaves
Pipal leaves (Ficus religiosa)
Local name: Pipal tree
Pipal trees grow throughout India. The trees remain green throughout the year. Considerable research has been conducted on the use of pipal leaves as livestock feed.
Nutritive value
The palatability and nutritive value of pipal leaves is not very good. Leaves when fed alone could form a maintenance ration. On an average, the leaves contain 5.47% DCP, and 39.22% TDN. The DCP content is fairly high as compared to conventional fodders. The TDN value is lower as compared to poor type roughages. Studies revealed that various nutrients in the leaves varied during different months and seasons. The leaves along with other sources of TDN could form a ration during scarcity periods.
It is a big spreading tree and is found in all parts of the country, remain green throughout the year.Palatability and nutritive value are not very good. DCP is 7.05%, TDN is 48.22 %. DCP content fairly high as compared to conventional fodders while TDN value is lower. The Copper content is highest in F. religiosa leaves. (Murugan et.al., 2012).The leaves of peepal (Ficus religiosa) have DM36.3%, OM 83.5%, CP 9.3%, EE 2.9%, CF 26.1%, NFE45.3%, TA16.6%, NDF47.6%, ADF33.1%, HC14.4%, 2.4% Ca, 0.22% P, 1.46 % Tannin and 0.57% Oxalate, on DM basis (Niranjan et.al., 2007)
Banyan leaves (Ficus bengalensis)
This tree is large spreading and grows throughout India.Banyan tree leaves play a vital role in feeding of goats and other ruminants in lean periods.The leaves are consumed in greater quantities by goats as compared to bullocks.It has3.81% DCP and 49.78 % TDN.
Subabul (Leucaena leucoephala)
Subabul is a vigorous rapidly growing drought tolerant tree and can be grown under wide range of agro climatic conditions. Yield is 50 tonnes/ha/annum. It has DCP 11.73% and TDN 51.97 % in cattle, 16.03 and 61.58 in goats. Leaves are rich in carotene and calcium and provides a valuable source of protein, energy and Sulphur for the rumen bacteria.Seed of subabul contains mimosine 4.47 % which causes loss of hair or wool leading to skin lesions and salivation. It should not be fed excessive to ruminants as it affects thyroid function and reduces the level of tri-iodothyronine and tetra iodothyronine leading to goitre. Mimosine on degradation products 3,4-dihydroxy pyridine – cause poor growth, alopecia, swollen and rough coronary bands, lameness, mouth and oesophageal lesions, depressed thyroxine levels and goitre. It also contains tannin 4.4 %. Goats can utilize subabul efficiently than sheep.Supplementation of Leucaena leucoephala to small ruminant provided higher concentrations of rumen metabolites, which naturally improved rumen function and digestibility (Bonsi et al., 1995)
Ber leaves
Ber leaves (Zizyphus jujuba)
Local name: Beri
Zizyphus jujuba is a commonly grown shrub, whose leaves are used as a conventional fodder for sheep and goats. In arid zones, it is an important fodder for these two species of animals. Ground leaves used in combinations with other feeds in dry season in Rajasthan. Entire shrub can be cut, leaves allowed to dry and beaten off with sticks. Dried product called pala (a generic term for dried leaves collected as livestock feed) and yielding at 1.0-1.6 kg dry matter per tree.
Nutritive value
In a comparative study on the palatability of different varieties of tree leaves; it was observed that beri leaves are comparatively more palatable than pipal or pakar leaves. The beri leaves have high crude protein content (18.6%) but the digestibility coefficient is only 36%.
Beri leaves are used as a conventional fodder for sheep and goat. They are comparatively more palatable than pipal leaveshaving high CP (18.6%) but digestibility coefficient only 36.
Cassava leaves (Manihot esculenta)
It is a tuber crop extensively grown in Kerala and parts of Tamil Nadu. Cassava leaves are rich in essential amino acid especially lysine with high carotene content and thus can be used to supplement cereal diet which are deficient in lysine.It hasDCP 8.3% and TDN 45.5%.Leaf meal contains 7.6 mg of HCN/100g.For growing calves 2.27 kg of partially dried tapioca leaves could replace 0.68% of GNC. For milch cattle ration 50% of GNC can be replaced by tapioca leaf meal.
Bamboo leaves
Bamboo leaves (Dendrocalamus strictus)
Local name: Bamboo
Bamboo trees grow in large parts of India. Large quantities of leaves become available during harvesting for paper manufacture. It is estimated that about 90-150 tonnes of leaves can be obtained from one hectare of bamboo forests.
Nutritive value
Bamboo leaves are rich in protein. The leaves in tender stages are relished by the animals and can form a part of the ration. Several studies shown that bamboo leaves are important source of roughage for feeding of livestock.
Bamboo plant is used as fodder especially during drought when other feed crops are scarce.Large quantities of leaves become available during harvesting for paper manufacture.It has DCP 9.3% and TDN 48.8%.The leaves in tender stages are relished by the animals and can form a part of the ration.Bamboo leaves tend to have higher protein levels in the winter and lower levels during spring and summer.Total non-structural carbohydrates in bamboo leaves decreased throughout the growing season, and then remained stable or increased during winter.Feeding 4-5 Kg of green leaves of bamboo in its raw form to the cow after parturition helps in early dropping of placenta by animal within half an hour of feeding.
Babul (Acacia nilotica)
The CP content of babul leaves is 23% and DM yield of tree leaf fodder is 0.2 to 2.0 ton/ha/year (Rai, et.al, 2007). As a fodder source, babul pods and leaves are fed to livestock. Pods and leaves are protein rich feedstuff, generally dropped during the dry season and thus providing nutritive feed during scarce periods.Babul is N-fixing legume that can be grown with grass or cereal crops in order to enhance their N value.It contain high levels of condensed tannins (from 5.4% in pods to 15.8% in twigs) that may hamper protein digestibility and, hence, animal performance. Other compounds such as alkaloids, Saponins have Antinutritionaleffects.
Agathi (Sesbania grandiflora)
It is also a leguminous fodder tree. Leaves haveDCP 16.89 %, TDN 61.80 %and isvalued as a fodder for feeding of cattle and goats, particularly for dry season. Annual yield is 27 kg of green leaf/tree/year.Cattle fed 5 kg fresh leaf/day showed increased milk yield by 8%. Supplementation with Sesbania grandiflora of goats fed guinea grass hay increased intake by 25% and supported a positive N balance.
Neem leaves (Azadirachta indica)
Local name: Neem
Neem trees grow all over India. The plant remains green throughout the year and is drought resistant. Large quantities of leaves become available if judiciously collected. Neem is a large and evergreen tree with edible fruits and aromatic leaves found throughout southern Asia. A mature tree can produce 350 kg of leaves a year, which may be used for feeding cattle during famines.
Nutritive value
The neem leaves are not relished by the animals. Buffaloes consume about four to six kilogram. The nutritive value is 6.19% DCP and 50% TDN. After the oil has been pressed from the seeds, the cake is used as fertilizer, but it can also be used as feed. Up to 10% neem cake may be included in concentrates for cattle and up to 5% for poultry. The oilcake has a very bitter taste. Leaves and cakes are used as anthelmintic for goats and is said to give healthy looking animals when fed.
Deleterious factor
The terpenoids azadirachtin and limonin impart a bitter taste and the leaves of A. indica are therefore not relished by cattle.
Neem plant remains green throughout the year and is drought resistant. Neem leaves contain appreciable amount of protein, minerals and carotene (185ì g/g) and adequate amount of trace minerals except zinc.It is consumed by camels, Goats and cattle in drought.Fallen leaves can also be fed but are less palatable. Leaves contain about 8 % protein, DCP- 6.19%, TDN 52.51%andME 1926kcal/kg.
Glyricidia (Gliricidia sepium)
Glyricidia is second most important multipurpose tree legume after Leucaena leucocephala in the humid tropics. It is one of the few forage tree species capable of leaf yields comparable to those of leucaena and it can grow on a wider range of soils tolerating low pH. The yield is 2 t/ha/year to 20 t/ha/year.Gliricidia sepium leaves have a high feeding value, with CP 20-30%. Animals seem to refuse gliricidia leaves on the basis of smelldue to volatile compounds released from the leaf surface. Leaves are also relatively low in tannins compared with other forage tree legumes. The toxicity can be seen due to the conversion of coumarin to dicoumerolby bacteria, a haemorrhagic compound, during fermentation. Wilting gliricidia leaves for 12-24 h before feeding – increase intake.
Banana leaves (Musa spp.)
Banana leaves are usually fed when the trees are chopped following fruit harvesting. Leaves are palatable, relatively rich in crude protein and have laxative effect.Cattle and goat relish leaves but diarrhoea was apparent within a week when only leaves were fed.When fed to bulls with paddy straw and oil cake, there were no digestible troubles.
Jack fruit (Artocarpus heterophyllus)
Jack fruit trees are widely spread in tropical countries and are extensively used for feeding cattle, sheep and goats. It is fed particularly in Kerala, Maharashtra, Orissa and West Bengal.Leaves have DCP 4.8% and TDN 43.3%. Leaves should be supplemented with either wheat bran or rice polish as the leaves alone do not meet maintenance requirement of the animals.
Kachnar (Bauhinia variegate)
Kachnar is a very common fodder tree cultivated in India.It is palatable to cattle, sheep and goat. Leaves haveDCP 7%, ME 1.5 Mcal/kg DM. TheTannin content is fairly high around 1.5%.
Khejri(Prosopis cineraria)
Khejri is a major fodder trees in semi-arid regions of India.In some areas of Rajasthan and Gujarat, there is an established tradition of preparing leaf meal from Prosopis cinereria and conserving it for use in summer. The leaves have a relatively high crude protein content (15-16%) whiledigestibility is usually low.Low crude protein digestibility of P. cineraria had been attributed to the presence of high levels of tannins 160 mg/g, with a protein precipitating capacity of 10.6%. Annual production of forage is 190 kg/tree
Oak (Quircus incana)
Tree leaves contained 10.2% CP and 92-95% OM. Fermentation of oak leaves with Sporotrichum pulverulentum decreased the contents of total phenols and condensed tannins by 58 and 66% respectively in 10 d. The protein precipitation capacity decreased by 65%
