Leucaena leucocephala leaf meal as supplement to diet of grazing dairy cattle in semiarid Western Tanzania

The effect of supplementation with three levels of Leucaena leucocephala leaf meal (LLM) added to a diet composed of cotton seed hulls (CSH) and maize bran (MB) on milk yield, milk composition and body weight changes of grazing lactating cows was studied in a completely randomised design. Marginal product analysis for the different levels of LLM as a substitute to cotton seed cake (CSC) was also calculated. The following treatment diets were used in the experiment: Diet 1, (control) composed of 1.8 kg DM CSH and 1.8 kg DM MB. Diet 2, 3 and 4 had an addition of 1.2, 2.0 and 2.6 kg DM of LLM respectively. Diet 5 was composed of 1.8 kg DM of CSC and 1.8 kg DM of MB. Treatments, number of lactations, farm and initial milk yields significantly (P < 0.01) influenced milk production. LLM supplementation to grazing cows significantly increased milk production, weight gain and milk composition (P > 0.05). Cows on treatment 1 achieved no significant (P < 0.05) increase in milk yield compared to cows on treatment 2, 3, 4 and 5 which attained net milk increase of 3.6, 4.1, 6.7 and 4.4 litres/cow/day respectively. There was no significant (P > 0.05) difference in net milk produced by cows on treatment 2, 3 and 5 compared to treatment 1. LLM supplementation significantly (P < 0.05) increased total solids (TS) in milk compared to that of cows under control, but there was no significant (P > 0.05) influence on milk crude protein (CP), butter fat (BF), solids not fat (SNF) and ash in all the diets. Body weight was significantly (P < 0.05) increased by LLM supplementation. Degradation coefficients of the treatment diets were high and varied significantly (P < 0.01) and had an influence on the metabolizable energy value of the treatment diets. Cows on diet 2 to 4 had a weight gain of 190.9, 101.8 and 80.9 g/cow/day respectively and cows on diet 5 attained the highest weight gain (234.5 g/cow/day). Diet 4 had the highest marginal productivity of 4.3 followed by diets 2, 3 and 1 with marginal productivities of 2.8, 0.6 and 0 respectively. It was therefore, concluded that the optimal supplementation level using LLM as a substitute for the more expensive CSC was diet 4.This revised version was published online in November 2005 with corrections to the Cover Date.     

The Potential of Albizia lebbeck as a Supplementary Feed for Goats in Tanzania

Forty growing goats (20 males and 20 females) were used in a 90-day growth and intake study to evaluate the potential of Albizia lebbeck (ABC) based concentrate as compared with Gliricidia sepium (GBC), Leucaena leucocephala (LBC), and Moringa oleifera (MBC) based concentrates with cotton seed cake (CSC) as a control. The animals were fed a basal diet of maize stover and supplemented daily with 30 g/kg W^0.75 of ABC, GBC, LBC, MBC, and CSC. They were compounded so as to formulate iso-protein diets. Treatment effects were significant (p<0.05) for growth rates in that with the exception of GBC, goats on CSC exhibited significantly higher gains compared to counterparts in other treatments. The total DM intake was between 50.6 and 52.6 g/kg W^0.75/day and there were no significant (p>0.05) differences among treatments. There were significant differences (p<0.05) among treatments for maize stover intake. CSC based treatment showed the highest intake with insignificant (p>0.05) differences amongst the leaf meal based concentrates. It can be concluded that Albizia lebbeck had similar potential to the other leaf meal based supplements studied but had lower potential compared to a cotton seed cake based supplement, as protein sources for growing goats fed a poor quality basal diet.     

Intake, rumen digestion, digestibility and microbial nitrogen supply in sheep fed Cynodon nlemfuensis supplemented with Gliricidia sepium

Four Pelibuey sheep fitted with flexible rumen cannula were fed increasing levels of Gliricidia sepium foliage (gliricidia) in a 4 × 4 Latin square design. Treatments were: control, 10, 20 and 30% (dry basis) of gliricidia mixed in a basal diet of Cynodon nlemfuensis (stargrass) hay. Dry matter (DM), organic matter (OM) and crude protein (CP) intakes were linearly increased (P < 0.05) from 45.2, 40.4, 2.0 to 71.5, 63.3 and 6.8 g/kg W^0.75/d, for the control and the 30% gliricidia diet, respectively. Similarly, increments of gliricidia in the diet resulted in a linear increase in DM, OM and CP apparent disgestibilities from 43.7, 48.4 and 27.0 to 50.7, 54.7 and 57.3%, for the control and 30% gliricidia diet, respectively. There was no effect (P > 0.05) of supplementation with gliricidia on rumen dry matter digestion of stargrass. Microbial nitrogen (N) supply to the small intestine had a trend towards an increase from 4.9, for the control, to 9.6 g N/d, for the 30% diet, though it was not significant (P > 0.05). It is concluded that, gliricidia might be incorporated into low quality diets since it increases total DM intake, supplies highly degradable N to the rumen and appears to increase the microbial N supply to the small intestine of sheep. This revised version was published online in August 2006 with corrections to the Cover Date.     

Performance of Zebu Steers Grazing on Western Tanzania Native Forages Supplemented with <Emphasis Type="Italic">Leucaena Leucocephala</Emphasis> Leaf Meal

Information is lacking on the potential of leguminous fodder trees such as Leucaena leucocephala as a feed resource to supplement the native forages in traditional grazing management systems in the tropics. Two studies were conducted (1) to assess traditional fodder banks’ forage nutritive potential on animal production, and (2) to investigate the effect of Leucaena leucocephala leaf meal (LLM) supplementation on growth of steers grazing standing hay basal forages in the dry season. The traditional forages had low nutritive values indicated by low mean crude protein (CP) of 23 g kg⁻¹ dry matter (DM), and high fibre contents of 717, 546 and 153 g kg⁻¹ DM for neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL), respectively. The forages were poorly degraded in sacco and had low metabolisable energy (ME) (4.2–4.6 MJ kg⁻¹ DM). Mean washing losses A, slowly degradable DM fraction, B, potential degradability, (A+B) and mean 48 h DM degradability (DMD) of grazing land forages were 70, 471, 541 and 326 g kg⁻¹ DM, respectively. In the supplementation study, 16 growing steers (160.8±0.24 kg) were randomly allocated into four groups, in a completely randomized design. Four LLM treatment diets (T1, T2, T3 and T4), with four levels: 0, 0.4, 0.6 and 0.8 kg DM for control, low, medium and high LLM levels, respectively, were randomly allocated to the animals in the four groups for 70 days (d). LLM supplementation (p<0.05) improved mean weight gain from −0.30 to 0.26 kg steer⁻¹ d⁻¹, for T1 and T4, respectively. Steers on T4 gained (p<0.05) more weight compared to the animals in T1 and T2, though there was no (p>0.05) difference in weight gains between animals on T3 and T4 (0.14 vs. 0.26 kg steer⁻¹ d⁻¹, respectively). Standing hay basal forages alone could not sustain animal productivity during dry seasons unless corrected for protein. Higher levels of LLM supplementation prevented weight losses and improved the performance of grazing steers, a management practice thought appropriate to low income pastoralists in semiarid western Tanzania.     

Influence of forbs and shrubs on intake,digestibility, and nitrogen and energy balance in sheep fed low-quality straw

A 4×4 Latin square experiment (Exp) was conducted using eight Debouillet yearling wethers with two wethers/cell to compare the effects of forbs and shrubs supplementation to a low-quality barley straw with alfalfa hay (ALF) supplementation in terms of nutrient digestion and balance. Diets studied in the Exp were barley straw (0.56% N) and straw plus either 42% ALF, 63% forbs (a 50:50 mixture of scarlet globemallow and leatherleaf croton) or 62% shrubs (mixture of 50% fourwing saltbush and 50% mountain mahogany). Diets containing ALF, forbs and shrubs were isonitrogenous (1.68% N). Periods of each Latin square were 15 days with total fecal and urine collections obtained on the last 5 days of each period. Dry matter intake of ALF and shrub-containing diets was similar and higher (P<0.05) than straw alone or straw plus forb diets. Nitrogen (N) retention was improved, but NDF digestibility was reduced (P<0.05), in diets containing ALF and shrubs compared with straw only. No difference in N retention among diets were detected (P>0.05) when N intake was used as a covariate. Metabolizable energy (ME) content of all the diets was similar except the shrub containing diet that was lower than the straw plus forbs or straw plus ALF but similar to the straw diet. Forbs had little influence on digestion and N utilization in the Exp presumably because of their reduced acceptability in the dried and ground form by sheep. Results suggest that native shrubs used in the study influenced intake and N utilization in a manner similar to ALF; and forbs used were similar in ME to ALF.     

Effect of diet inclusion of <Emphasis Type="Italic">Tithonia diversifolia</Emphasis> on feed intake,digestibility and nitrogen balance in tropical sheep

Feed intake and digestibility were evaluated in sheep fed low quality Taiwan grass supplemented with Tithonia diversifolia. Four wether hair sheep were housed in metabolic cages and fed with either Control concentrate 20%, Tithonia 20, 35 or 50% in a Latin Square design. Adaptation and, feces and urine collection periods were 14 and 7 days, respectively. Feed intake was increased (P < 0.01) from 58.5 in control to 86.1 g/kg^0.75 in sheep fed Tithonia. NDF intake and digestibility were affected by Tithonia level. Nitrogen intake increased linearly (P < 0.01) with increase in feces and urine excretion. N retention was similar (P > 0.1) among sheep fed Tithonia, but different (P < 0.05) from control. Inclusion of Tithonia foliage at 20% of the DM diet of hair sheep improved their intake of low quality Taiwan grass and nitrogen retention. Higher levels of Tithonia in the diet, however, increase nitrogen loss in feces and urine.     

Feed intake and dietary preferences of sheep and goats offered hay and legume-tree pods in South Africa

Two experiments were designed to investigate the effect of legume tree-pods and ensiling on the intake and relative palatability of six feeds by goats and sheep. In the first experiment, the feeds offered were pasture hay (Themeda triandra), alfalfa (Medicago sativa), pods of Acacia sieberiana, Acacia nilotica and Leucaena leucocephala. In the second, silage from the pods of A. sieberiana was included as the sixth feed in order to examine the effect of ensiling on intake and palatability since this process was devised as a means of detoxifying cyanogenic glocosides known to be present in the leaves and pods of this species. Intake (Ti) and relative palatability (Pi) were determined using 3 goats and 3 sheep in each experiment. Since the feeds had different dry matter contents, intake was expressed as a ratio of the quantity offered (Ti/Ai). Using the hay offered (A1) and intake (T1), as standard, relative palatability indices were calculated as Pi = (Ti/Ai)/(T1/A1) where i represented the other feeds. In experiment 1, goats consumed more hay than alfalfa or pods. Sheep consumed more leucaena than all the other feeds. In experiment 2, the intake of all feeds except nilotica increased over time. Hay and leucaena had the highest Pi for goats and sheep, respectively, in experiment 1. In experiment 2, silage from pods of A. sieberiana had the highest Pi while the ranking for goats remained unchanged. The nilotica meal had the lowest Pi in both experiments. Pi was affected (p > 0.0001) only by feed type in experiment 1 but in experiment 2, feed type, animal species and weight significantly (p > 0.01) affected Pi. The results show that the pods of L. leucocephala and A. nilotica were the most and least preferred by goats and sheep, respectively, and that ensiling significantly improved the intake and palatability of the pods of A. sieberiana. However, some feeds that are least preferred in times of abundance and variety could be relished during periods of scarcity and severe feed shortages, based on animal survival instinct.This revised version was published online in November 2005 with corrections to the Cover Date.     

Preference and Palatability of Indigenous and Exotic Acid Soil-tolerant Multipurpose Trees and Shrubs by West African Dwarf Sheep

Eleven acid soil-tolerant multipurpose trees and shrubs (MPTS) were assessed for preference and palatability with mature West African Dwarf (WAD) sheep using the cafeteria method. About 500 g each of the MPTS were weighed in triplicates into plastic feeding troughs and randomly placed around the perimeter of a Panicum maximum paddock (25 m × 25 m). Five ewes averaging 25.24 ± 0.69 kg were allowed 4 h access to the browse species daily for 12 d. Dry matter intake differed (p<0.05), ranging from 0.0 g in C. calothyrsus to 70.8 g in M. barterii. The number of animal visits, time spent and number of bites per visit on the browses also differed (p<0.05). There were positive correlations between DM intake and number of visits, number of bites, time spent on each fodder browsing and the coefficient of preference. The preference of the various MPTS by animals in descending order was M. barterii > A. cordifolia > L. leucoephala > B. monandra > D. guineensis > H. madagascariensis > T. tetraptera > T. africana > A. bella > B. grandiflora > C. calothyrsus.     

The effects of drying temperature on chemical composition and nutritive value of some tropical fodder shrubs

The effects of drying temperature on chemical composition and nutritive value of leaves of the shrub legumes Acacia angustissima (Miller) Kuntze, Calliandra calothyrsus Meissn and Leucaena leucocephala (Lam.) de Wit were determined in two studies in Zimbabwe. In the first study, the effects of shade-, sun- and oven-drying leaves on chemical composition and protein precipitation capacity of tannin extracts were studied. Drying method affected (P<0.01) chemical composition, with cell wall polysaccharides increasing from shade drying to oven drying. Calliandra calothyrsus leaves had the highest total phenolics, tannin phenolics and the lowest N content. About 40% of phenolics in L. leucocephala were non-tannin compared to less than 15% in A. angustissima and C. calothyrsus. Extractable proanthocyanidins and their capacity to precipitate protein were affected (P<0.01) by drying method; extracts from shade-dried leaves were 10% and 20% more reactive than extracts from sun- and oven-dried leaves, respectively. The relative degree of polymerisation of the proanthocyanidins was higher (P<0.01) for oven-dried (1.44) leaves compared to shade-dried (1.01) and sun-dried (1.00) leaves. Drying temperature influences the nutrient–polyphenolic interactions in A. angustissima, C. calothyrsus and L. leucocephala leaves and these interactions have important implications for feed evaluation protocols and for use of these leaves in ruminant feeding systems. The second study considered the effects of feeding sun-dried or fresh leaves of the three shrub legumes as supplements to native pasture hay on nutrient intake and digestion by goats. Feeding the fresh or dry leaves made no difference in terms of dry matter intake and digestion, and N digestion. This offers farmers flexibility in terms of feeding strategies, as they can feed the browse in any form that suits their farm situation. Increasing the level of C. calothyrsus in the diet increased faecal N. Nitrogen retention was lower for animals fed with C. calothyrsus compared to those fed with the other browses.     

Voluntary intake by sheep and goats ofGliricidia sepium fed in three states and at three levels of supplementation to a basal diet ofPanicum maximum

Crude protein content andin sacco dry matter (DM) loss after 72 h of incubation in West African dwarf (WAD) sheep and goats of fresh, wilted and dried leaves ofGliricidia sepium were compared. Additionally, voluntary DM intakes by WAD sheep and goats ofG. sepium leaves presented in the fresh, wilted and dried states at 10, 20 and 30% levels of supplementation were investigated in two separate experiments. The crude protein content and DM loss from dried leaves were relatively lower than fresh and wilted leaves. At all levels of supplementation, the voluntary DM intakes of fresh and wilted leaves by WAD sheep and goats were relatively higher than dried leaves. The results suggest thatG. sepium leaves should be fed either in the fresh or wilted states to WAD sheep and goats, at levels between 20 and 30% of the total daily DM allowance.     

Influence of forbs and shrubs on ruminal fermentation and digesta kinetics in sheep fed a grass hay/straw diet

Four ruminally cannulated, Debouillet wethers were used in a 4×4 latin square experiment to evaluate the influence of a forb mix, a shrub mix and alfalfa (ALF) hay on ruminal fermentation characteristics and digesta kinetics of a basal grass hay/straw (GH/S; 1.04% N) diet. The grass hay was mostly blue grama (Bouteloua gracilis) mixed with barley (Hordeum vulgare) straw. Wethers were fed either the GH/S mix (7030), GH/SALF (295813), GH/Sforbs (265420), or GH/Sshrubs (265420). The forb component consisted of equal parts of scarlet globemallow (Sphaeralcea coccinea) and leatherleaf croton (Croton corymbulosus) while shrubs were composed of equal parts of fourwing saltbush (Atriplex canescens) and mountain mahogany (Cercocarpus montanus). Ruminal pH, ammonia-N, as well as total VFA concentrations and molar proportions of individual VFA did not differ among diets. Particulate passage rates tended (P>0.10) to be greater for diets containing ALF, forbs or shrubs (2.8, 2.9 and 2.8% h^–1) than the GH/S diet (2.5% h^–1). In situ DM and NDF disappearance of a GH/straw (5050) mix did not differ among treatments at most incubation times, except at 96 h when extent of both DM and NDF disappearance were greater (P<0.05) in sheep fed either forbs or shrubs than in those fed other diets.     

Effect of low-protein diet with supplementing different levels of DL-methionine on production performance of minks in growing-furring period

A study was conducted to evaluate production performance of minks in growing-furring period with supplementing DL-Methionine (Met) in low protein diet. Seventy healthy male minks were randomly divided into five groups of 14 minks each. The minks were fed in five kinds of experiment diets (HP, LP, LP+M1, LP+M2 and LP+M3). The dietary protein levels, expressed as percentage of dry matter (DM), were 32% (high protein, HP) and 24% (low protein, LP). LP was supplemented with Met 0.4% (M1), 0.8% (M2) and 1.2% (M3) DM. From mid of September to December 10, apparent digestibility of CP (crude protein), N intake and urinary N excretion were decreased with declining dietary protein levels (p < 0.05) and N retained was the highest in treatment LP+M2. No significant difference was found in total serum protein (TP) and serum urea nitrogen (SUN) among all treatment groups (p > 0.05). Skin length of treatment HP and LP+M2 was higher than that of other groups (p < 0.05). Body length, skin weight, length of guard hair and under hair were not affected by different dietary protein levels (p>0.05). The best performance could be observed in treatment LP+M2. In diet, 24% (DM) protein level with 1.54% Met supplementing was enough for minks during growing-furring period. Dietary protein lowered from 32% to 24% with supplementing Met in diets would result in a 37.9% decrease in urinary N excretion. Furthermore, addition of Met in diets for minks would be beneficial in terms of reducing feed expenses and lessening nitrogen emissions to the environment.     

Improving rumen fermentation and milk production with legume-tree fodder in the tropics

Feeding leguminous fodder that is high in protein can improve rumen fermentation parameters leading to increased digestibility and intake of low quality fibrous feeds, and hence improved animal production. The effect on dry matter (DM) degradation and rumen fermentation parameters of feeding urea or tree legume foliage (Erythrina poeppigiana or Gliricidia sepium), as protein supplements to a basal diet of Hyparrhenia rufa hay, rice bran and molasses, was studied with rumen fistulated steers (Zebu × Creole crossbreeds). In a second experiment, Jersey × Creole crossbreeds were used to determine the effect of the above three treatments on milk production. Both experiments were conducted at CATIE's experimental farm, Turrialba, Costa Rica (9°58 N; 83°31 W; 639 m above sea level; mean annual precipitation of 2600 mm; mean daily temperature 22 °C). The disappearance of hay DM in the rumen increased with time to 144 hours and potential degradation of hay DM was significantly higher (P < 0.05) for the legume diets compared to urea but there were no differences between legume species. Legume based rations resulted in total volatile fatty acid concentrations of rumen licor that were 15 to 24% higher than for urea based rations (P < 0.05). The concentration of rumen NH₃-N was highest two hours after feeding and tended to decrease in time. The urea ration resulted in significantly higher NH₃-N than the legume rations, reaching 45 mg/100 mL two hours after feeding. Milk yields did not differ (P > 0.05) when cows received either E. poeppigiana or G. sepium foliages as protein supplements (7.3 and 7.4 kg milk/cow/day, respectively) but they were superior (P < 0.05) to urea supplementation (6.7 kg milk/cow/day).     

In vivo digestibility and nitrogen balance in sheep diets with foliage of fodder trees in substitution for soybean meal

Apparent digestibility and nitrogen (N) balance were evaluated in sheep fed low-quality Cynodon nlemfuensis grass supplemented with different foliages of forage-potential trees. Four male hair sheep were housed in metabolic cages and fed in a Latin Square design with 30 % inclusion of foliage of Erythrina indica (Ei), Moringa oleifera (Mo), or Trichanthera gigantea (Tg) replacing soybean meal. Adaptation and faeces and urine collection periods were 14 and 7 days, respectively. Sheep received 70 g DM/kg/BW^0.75 of the diet in order to achieve total consumption of feed. Dry matter, organic matter, and neutral detergent fiber digestibilities were similar (P > 0.05) among the control, Mo, and Ei diets, while the Tg diet resulted in the lowest (P < 0.05) value. The Ei diet showed the highest (P < 0.05) total N intake among the three diets with 30 % of leaf meal, which was similar (P > 0.05) to the control diet. N excreted in faeces was highest (P < 0.05) in the Tg diet when compared to the other leaf meal diets, in which the Mo diet presented the lowest (P < 0.05) value, but was similar (P > 0.05) to that found in the control diet. The Mo and Ei diets had similar (P > 0.05) values for the percent of N absorbed by the animals, which was much higher (P < 0.05) than that of the Tg diet. The forage of M. oleifera and Ei can be used in diets at 30 % incorporation to substitute the use of soybean meal in small ruminant production.     

Forage dry matter yields and psyllid resistance of thirty-one leucaena selections in Hawaii

Forage yields ofL. leucocephala (Lam). de Wit have been reduced as the result of psyllid damage sinceHeteropsylla cubana Crawford invaded the Hawaiian Islands in 1984. The forage productivity and psyllid resistance of 31Leucaena species and interspecific hybrids were assessed from 5 harvests in Hawaii during 1991 and 1992. The trial consisted of an augmented randomized complete block with 22Leucaena selections in all 4 replicates, 2 selections in 3 replicates and 7 selections in 1 or 2 replicates.Forage (leaves and stems < 6 mm diam.) dry matter (DM) biomass yield over a 13-month period ranged from 1.4 to 34 Mg ha^–1 from total DM ranging from 1.9 to 63.7 Mg ha^–1. Percent forage fractions ranged from 49 to 78% (forage DM/total DM). The 10 selections in this trial of eitherL. pallida Britton & Rose, and its hybrids withL. leucocephala consistently produced both the highest forage and total DM yields averaging 22 and 40 Mg ha^–1, respectively. This represented a three-fold increase in forage production when compared toL. leucocephala K636 (a standard around the world).The excellent performance of theL. pallida lines was attributed to high psyllid resistance and seedling vigor. AllL. pallida selections with the exception of K953 exhibited good psyllid resistance.Leucaena diversifolia Benth. K749,L. pallida K376, andL. esculenta (Moc. & Sesse) Benth. K950 had the highest psyllid resistance (p<0.05). Psyllid damage was negatively correlated to forage DM yield at both harvest 2 and 5 (r=–0.55,p<0.01,n=94). Forage DM was positively correlated to seedling vigor for the first harvest (r=0.83,p<0.001,n=74) and combined harvests (r=0.88,p<0.001,n=74).     

Vernonia amygdalina as a supplement to teff straw (Eragrostis tef) fed to Ethiopian Menz sheep

Sixteen rumen fistulated Ethiopian Menz type sheep were used in a completely randomized block design (CRBD) in experiment 1. Unchopped teff straw was fed alone or supplemented with either 100, 150 or 200 g/d of sun-dried vernonia leaves. The chemical compositions of fresh, boiled, water-soaked and sun-dried vernonia and soluble carbohydrate (SC) loss by boiling were determined. In experiment 2,25 growing Ethiopian Menz type sheep, were fed teff straw alone or supplemented with 120 g (DM) of either boiled (B) or soaked (S) fresh vernonia with or without molasses (M) (50 g). SC lost by boiling fresh vernonia for 15, 30, 45 or 60 min was determined.In experiment 1, boiling increased the nitrogen (N) concentration in vernonia but sun-drying reduced it. N bound to fibre (NDF-N) was reduced by boiling but not by soaking. SC loss increased with boiling time. Supplementation did not affect the degradation constants (a, b, PD, c) of teff straw, but DM disappearance was increased (p<0.05) at 76 and 120 h of incubation. Intake of sun-dried vernonia was poor but increased with quantity offered. Intakes and digestibilities of DM, OM and the fibre fractions were marginally higher (p<0.05) in the supplemented diets. Nitrogen balance in the supplemented diets was low due to increased faecal and urinary excretion. In experiment 2, rumen NH₃–N was higher for the boiled treatments compared to the soaked treatments. Acceptability at both 2 and 4 h was highest for BM, followed by SM, B and S. Boiling for 30 min, but not soaking, enhanced the acceptability of vernonia, suggesting that a pretreatment may enhance the feed value of vernonia.     

Rumen degradation in sheep,goats and cattle and voluntary intake by sheep of four browse species

Two experiments were conducted using dried leaves ofAlchornea cordifolia, Ficus capensis, Manniophytum fulvum andAlbizza niopoides. In Experiment 1, dry matter (DM) degradation characteristics were investigated using thein sacco nylon bag technique in West African Dwarf (WAD) sheep, WAD goats and Bunaji steers. In Experiment 2, voluntary intake of the browse forage when fed as supplements to sheep at 0, 10 and 30% levels was measured. In Experiment 1,A. cordifolia andM. fulvum had significantly higher rapidly degradable DM fraction thanA. niopoides andF. capensis. Averaged across browse species, the extent of DM degradation for sheep (58.3%) was significantly higher than for goat (47.7%) or cattle (44.1%). Ranking order of browse species for the extent of DM degradation was:F. capensis>A. cordifolia=M. fulvum=A. niopoides. In Experiment 2, as the level of supplementation increased from 10 to 30%, voluntary intake ofA. niopoides andM. fulvum increased while voluntary intake ofA. cordifolia andF. capensis declined. The results suggest that dried leaves ofA. niopoides andM. fulvum are more acceptable to WAD sheep than those ofA. cordifolia andF. capensis.     

Effect of Air-filled Porosity and Organic Matter Concentration of Soil on Growth of Picea abies Seedlings after Transplanting

The effects of air-filled porosity (AFP) and organic matter concentration (OMC) of soil on the growth of Norway spruce [Picea abies (L.) Karst.] seedlings were studied in a greenhouse experiment. One-year-old seedlings were planted into 250 pots filled with five different growth media based on low-humified sphagnum peat and fine sand. The media were mixed to achieve five levels of OMC (1, 25, 50, 75 and 97% by mass). Five AFP levels (5, 10, 20, 30 and 40%) were applied to the mixtures of growth media during irrigation. The growth attributes of the seedlings were measured after seedlings had grown in the greenhouse for 15 weeks. The shoot height and mass growth as well as root mass were significantly higher in 20, 30 and 40% AFP than in 5 and 10% AFP (p<0.05). The longest shoots were produced in growth media with 25, 50 and 75% OMC (p<0.05). The effect of OMC on root mass, while significant (p=0.03), was less pronounced than the effect on height growth and mass of the shoots (p<0.001). The results indicate that, for good seedling growth in pots in greenhouse conditions, AFP should be 20-40% and OMC 25-75% in the growth medium.     

Intake,digestibility, nitrogen balance and certain rumen characteristics of Ethiopian Menz sheep fed teff straw supplemented with cotton seed cake,dry sesbania,dry leucaena or fresh leucaena

Twenty five rumen fistulated Ethiopian Menz sheep were used in a completely randomized block design to determine roughage utilization when different types of supplements (sesbania, leucaena, cotton seed cake (CSC)) and forms (fresh or dry leucaena) were fed. The chemical composition, intake, digestibility, nitrogen balance and rumen degradability coefficients were determined. Rumen pH and ammonia-nitrogen (NH₃-N) levels were estimated in samples taken at 1, 2, 3, and 6 h after feeding.There was substitution of teff straw dry matter by the supplements. Fresh leucaena effected the highest substitution. Supplementation enhanced (p<0.05) the dry matter degradation (DD) of teff straw at 6 and 12 hours of incubation but not (p>0.06) for the other incubation times. There were no significant differences (p>0.05) between treatments in the degradation constants: readily soluble component (a) slowly degradable fraction, (b) potential degradability (PD=a+b) and rate of degradation (C) and for rumen NH₃-N concentration, the ranking was CSC > sesbania > dry leucaena > fresh leucaena > teff straw alone (p<0.05). The particularly high substitution rate observed with fresh leucaena might suggest that bulkiness may be a limiting factor in the intake of low quality roughages supplemented with tree leaves. The lower DM and OM digestibilities of the supplemented diets were attributed to substrate preference by rumen cellulolytic bacteria. Excessively high levels of rumen NH₃–N (328 mg/l) in the CSC diet resulted in high urinary nitrogen losses (r ²=0.32;p<0.001) leading to low N balance. This may suggest that for the utilization of poor quality tropical roughages, moderate levels of rumen NH₃–N sustained over a longer period may be needed.     

Forage potential ofErythrina abyssinica: intake,digestibility and growth rates for stall-fed sheep and goats in southern Ethiopia

Feeding value ofErythrina abyssinica leaves were evaluated with native sheep and goats at Soddo, southern Ethiopia in a 21-day digestibility and 80-day growth trial. In the digestibility trial, wilted leaves ofE. abyssinica were fedad libitum, while in the growth trial, animals were offered a basal diet ofP. purpureum with three levels (0, 500, 1000 g/head/day) ofE. abyssinica leaf. No significant (P>0.05) differences were found between sheep and goats in voluntary intakes and digestibilities of organic matter, nitrogen and neutral detergent fiber. Supplementing a basal diet ofP. purpureum with increasing levels ofE. abyssinica leaves resulted in reduced intake ofP. purpureum, but increased total organic matter intake in both species. Liveweight gains of sheep and goats increased linearly (P<0.01) with increasing levels ofE. abyssinica leaf supplementation. Sheep gained weight faster (P<0.04) than goats.Based on the results it was concluded thatE. abyssinica has high forage potential and can effectively serve as a cheap source of protein supplement for low quality diets during the dry season for resource-poor farmers with stall-fed sheep and goats.