Sacco Dry Matter Degradability Research Articles

Influence of a Fusarium culmorum inoculation of wheat on the progression of mycotoxin accumulation, ingredient concentrations and ruminal in sacco dry matter degradation of wheat residues

The Fusarium head blight (FHB)-susceptible winter wheat cv. Ritmo was inoculated with spores of Fusarium culmorum at the beginning of full blossom. Samples of whole wheat plants were taken once weekly from anthesis until harvest and subsequently fractionated into straw, glumes and spindles, which were examined for deoxynivalenol (DON) and zearalenone (ZON). Additionally, the content of crude protein (CP) and non-starch polysaccharides (NSP) was scrutinized. Synthesis of the Fusarium toxins DON and ZON generally differed in terms of date of formation and concentration. Final mean DON concentrations of 37.5, 28.1 and 5.0 mg/kg DM were measured in glumes, spindles and straw, respectively, at the time of harvest. At this time, maximal mean ZON concentrations of 587, 396 and 275 μg/kg DM in spindles, glumes and straw, respectively, were determined. Moreover, Fusarium infected wheat residues contained higher CP but lower NSP contents at the last three sampling dates. In addition, collective samples of wheat straw and chaff were taken to investigate the effect of the Fusarium contamination on their in sacco DM degradation in dairy cows. Samples were analysed for mycotoxins and selected quality parameters. The dried and milled collective samples of straw and chaff were weighed into nylon bags and subjected to ruminal incubation for 4, 8, 16, 24, 48, 72, 96 and 120 h in two dairy cows equipped with a permanent rumen cannula. Marked differences in level of mycotoxin contamination as well as in ingredient composition between the variants of straw and chaff were detected. Moreover, after 120 h rumen incubation the in sacco DM degradation of inoculated straw and chaff were lower compared to the accordant controls. The soluble fraction was increased in inoculated samples, whereas a diminishment in the potentially degradable but insoluble fraction was more pronounced. Thereby, a decrease in the potential degradability was obtained for inoculated straw and even if less pronounced for chaff compared to the non inoculated corresponding controls. In conclusion, infection with F. culmorum of wheat involves an increased risk of mycotoxin contamination in straw. Also, a Fusarium infection may have an impact on chemical composition and may result in Fusarium growth-related modifications of host cell wall components.

Effect of Microwave Treatment on Chemical Composition and In sacco Digestibility of Wheat Straw in Yak Cow

Wheat straw was treated with microwave for 4 min and 8 min at a power of 750 W and frequency of 2,450 MHz. Chemical compositions of untreated, 4 min treated and 8 min treated Straws were analyzed and in sacco degradabilities of all these straws in yak rumens were measured. Microwave treatment didn't significantly (p > 0.05) affect the chemical composition of the straw. In sacco dry matter (DM) degradability of the straw after 18 h incubation in rumen was significantly (p 0.05) affected by microwave treatment. In sacco organic matter (OM) degradability of the straw was increased (p < 0.01) by around 20% for both the 4 min and 8 min microwave treatment, that of acid detergent fibre (ADF) was increased (p < 0.01) by 61.6% and 62.8%, and that of ash free ADF was enhanced by 72.1% and 69.6% for the 4 min and 8 min microwave treatment respectively. No significant difference was observed between the 4 min and 8 min microwave treatment on the degradability of DM, OM, CP, ADF and ash-free ADF of the straw.

Effect of N fertilizer on the productivity and nutritive values of perennial grass mixtures in the alpine region of Qinghai-Tibetan Plateau, China

A study was conducted on grass mixtures that included smooth bromegrass (SB) + drooping wild ryegrass (DW), smooth bromegrass + Siberian wild ryegrass (SW) + crested wheatgrass (CW) and smooth bromegrass + Siberian wild ryegrass + drooping wild ryegrass + crested wheatgrass in the alpine region of Qinghai-Tibetan Plateau. The study was conducted from 1998 to 2000 to investigate the effects of N application rates and growing year on herbage dry matter (DM) yield and nutritive values. Herbage DM production increased linearly with N application rates. The effect of N application on DM yields was greater (P &lt; 0.05) in the 2nd and 3rd production years than in the establishment year. Dry matter yields of SB + SW + CW and SB + SW + DW + CW can reach as high as 15 000 kg ha-1 at 345 kg ha-1 N rate in the 3rd growing year. With increased N application rates, crude protein (CP) contents and 48 h in sacco DM degradability of grasses increased (P &lt; 0.05). No effect (P &gt; 0.05) of N application was detected on organic matter (OM) and acid detergent fibre (ADF) concentration. It can be concluded that for increased biomass production in the alpine region of the Qinghai-Tibetan Plateau, a minimum of 345 kg N ha-1 should be applied to grass stands in three split application of 115 kg N ha-1, in early June, early July and late July. Key words: Nitrogen levels, herbage dry matter yield, leaf shoot ratio, crude protein contents, dry matter degradability

Influence of aFusarium culmorum inoculation of wheat onin sacco dry matter degradation of wheat straw and wheat chaff

The aim of this study was to investigate the effect of aFusarium culmorum inoculation of wheat on thein sacco dry matter degradation (DG) of wheat straw and wheat chaff in dairy cows. The ruminal disappearance of dry matter was measured with thein situ nylon bag technique. Samples of wheat straw and wheat chaff from non-inoculated andFusarium-inoculated wheat were used to examine the ruminal dry matter degradability. Samples were subjected to ruminal incubation in two dairy cous fitted with a permanent rumen fistula and incubated for 4, 8, 16, 24, 48, 72, 96 and 120 h. To describe the degradation kinetics, the equation by Ørskov and McDonald (1979) was used. DG rates obtained for contaminates straw and chaff were higher compared to the corresponding rates of the non-contaminated samples, which is assumed to be due to the activity of fungal enzymes. It can be concluded that an infection of wheat withF. culmorum may have an influence on the dry matter degradation of straw and chaff.

Effect of glyphosate contaminated feed on rumen fermentation parameters and in sacco degradation of grass hay and corn grain

Four rumen fistulated wethers were used to investigate the effect of glyphosate contaminated feed on rumen fermentation. The rations were based on corn silage, urea and a vitamin-mineral premix, either in the absence or presence of 0.77 g glyphosate per kg DM. Furthermore, rations were fed either with or without aromatic amino acid supplementation. During four periods of 28 days, sheep received each of the four dietary treatments according to a Latin square. After 14 days of adaptation rumen fermentation parameters (pH, ammonia, volatile fatty acids) were measured on day 15 over a five-hour period after the morning feeding. The remaining 13 days served for in sacco degradation studies with grass hay and corn grain. Ammonia (NH3) and pH of rumen fluid were within the normal range for all dietary treatments (NH3: 9.1 – 32.3 mmol·l − 1, pH: 6.2 – 6.7). Neither rumen fermentation parameters nor in sacco DM and NDF degradation of incubated feedstuffs were significantly affected by glyphosate, with or without aromatic amino acid supplementation. Kinetic profiles of the in sacco dry matter and NDF degradation of grass hay were almost identical for the dietary treatments.

Productivity and nutritive value of some cultivated perennial grasses and mixtures in the alpine region of the Tibetan Plateau

AbstractThe productivity and nutritive value of some cultivated perennial grasses, Bromus inermis (B), Elymus sibricus (S), E. nutans (N), Agropyron cristatum (A), Poa crymophila (P) and mixtures B + N, S + A, B + S + A, S + B + N, N + S + A, B + S + N + A, B + N + A + P, B + S +A + P and S + N + A + P, in the alpine region of the Tibetan Plateau were investigated. Elymus nutans and E. sibricus and the mixtures, B + S + N + A, B + S +A + P and S + N + A + P, were most productive with yields of dry matter (DM) of between 11 000 and 14 000 kg−1 of biomass annually in the second harvest year. Acid‐detergent fibre (ADF) concentrations increased (P &lt; 0·05), and crude protein (CP) concentrations and in sacco DM degradability values decreased (P &lt; 0·05) with the maturity of the cultivated grasses. Swards, based on these species and mixtures, have the potential to be the main choices for cultivation in the Tibetan Plateau because they produce more nutrients than other grass species and mixtures. Late August (flowering stage of dominant grasses) is the optimum time for harvesting as the yield of rumen‐degradable CP is highest that of DM relatively high and the DM degradability is satisfactory.

In sacco dry matter and nitrogen degradation and their relationship with in vitro dry matter digestibility of Napier grass (Pennisetum purpureum Schumach.) as influenced by height of plant at cutting

In vitro dry matter digestibility (IVDMD) as well as in sacco rumen dry matter degradability (DMD) and nitrogen degradability (ND) studies of Napier grass (Pennisetum purpureum) were carried out using a 3 3 factorial experiment arranged in a randomised complete block design with 3 replications. The treatments were 3 levels of nitrogen (N) fertiliser (0, 46, bacterium Synergistes jonesii is known to degrade these compounds and inoculation of the bacterium into the rumen protects cattle against mimosine and DHP toxicity. We report on the development, production, and storage of an in vitro, fermentor-based, mixed bacterial inoculum, which includes S. jonesii, for administration to cattle. This technique may be applicable to the production and delivery of other live, anaerobic, bacterial inocula for use in animal agriculture.

Prediction of feed intake, digestibility and growth rate of sheep fed basal diets of maize stover supplemented with Desmodium intortum hay from dry matter degradability of the diets

The in sacco dry matter (DM) degradability of diets based on maize stover harvested at three stages of maturity and supplemented with graded levels of desmodium ( Desmodium intortum cv. Greenleaf) hay were estimated from degradability of the individual feeds and their corresponding DM intake. The estimated DM degradability of the diets was used for prediction of DM intake (DMI), digestible DM intake (DDMI), DM digestibility (DMD) and growth rate of sheep feeding on the diets. The desmodium hay had significantly higher ( P<0.05) DM disappearance than the maize stovers after 4, 8, 16, 24 and 48 h of incubation, as well as higher washing loss ( A), degradation rate ( c value) and effective DM degradability (ED) than the maize stovers. The washing loss was lowest in maize stover harvested at stage III and, as a consequence, the washing loss of the diets showed a significant decrease ( P<0.05) with increasing stage of maturity of the stovers. The DM disappearance after 48 h incubation, washing loss and degradation rate showed a significant increase whereas the insoluble, but potentially degradable, fraction ( B) showed a significant decrease ( P<0.05) with increasing level of supplementation. The DM disappearance after 24 and 48 h of incubation, washing loss, ED and degradation rate showed strong positive correlation whereas the insoluble, but potentially degradable, fraction showed a negative correlation with DMI, DMD, DDMI and growth rate. On the other hand, the DM disappearance after 96 h of incubation, potential degradability and the lag phase showed very low correlation with these parameters. In general, the washing loss, ED and the DM disappearance after 24 and 48 h of incubation were found to be simple and reliable predictors of DMI, DDMI, DMD and growth rate. However, the use of the A, B and c values simultaneously in a multiple regression gave a more precise prediction of feed intake, digestibility and growth rate.

Phenotypic variation for in sacco dry matter and fibre degradation kinetics in lucerne

Energy content is an important criterion for evaluation in lucerne breeding. The in sacco method was used to investigate the phenotypic variation in the kinetics of degradation of dry matter and fibre for 15 lucerne cultivars grown in one location, and to compare these kinetic parameters with laboratory analyses of dry matter solubility, fibre content (NDF, neutral detergent fibre), and fibre solubility. Bags containing forage samples were incubated for 2, 4, 8, 12, 24, 48, and 72 h in 3 fistulated Holstein cows. Dry matter and NDF degradation curves were modelled with a sigmoid curve with 3 parameters. Phenotypic variations were observed for dry matter and NDF disappearance at each time interval, and for the parameters of the degradation kinetics. For both dry matter and NDF, the totally degraded fraction was correlated with the solubility measured by wet chemistry, but the rate of degradation of the slowly degraded fraction was not correlated with chemical analyses. The effect of the variations in the parameters of dry matter and fibre degradation on ruminant performance needs to be studied further.

Productivity and Nutritive Values of Different Fractions of Oil Palm (Elaeis guineensis) Frond

Productivity, nutrient contents, in vitro gas production and in sacco degradability of different fractions and whole OPF were determined to assess the feeding value of OPF as a ruminant feed. An in vivo digestibility trial was also carried out using goat. Freshly harvested OPF was randomly collected, partitioned and weighed. An OPF from 21 years older palm weighed 13.4 kg and the annual fresh matter yield of petiole, leaflet and midrib was 46.5, 11.8 and 3.4 ton/ha, respectively. Leaflet contained 439, 926, 698, 501, 168, 196, 748 and 52 (g/kg) of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose (CE), hemicellulose (HC), total carbohydrate (TC) and non fiber carbohydrate (NFC), respectively. Petiole contained lower (p<0.01) DM, CP and EE contents than leaflet. Organic matter, CE and TC contents were higher (p<0.01) in petiole compared to leaflet. Silica and lignin contents were highest (p<0.01) in midrib followed by leaflet, whole OPF and least in petiole. The Ca, P, Na, K and Mg contents (g/100 g DM) of leaflet were 0.529, 0.182, 0.039, 0.876, and 0.168, respectively. In vitro DM digestibility (g/100 g) at 48 h of leaflet, petiole and midrib was 32.7, 38.7 and 30.2, respectively. The in sacco DM degradation (g/100 g) at 48 h of leaflet was higher than that of whole OPF, petiole and midrib. The in vivo digestibility of DM, OM, CP and ADF of whole OPF was 52, 56, 43 and 26%, respectively. It can be concluded that leaflet is the most nutritious fraction of OPF and midrib is the least. The nutrient content and digestibility of the whole OPF showed that OPF could be an alternative roughage source for ruminant diets.

Morphological fractions of maize stover harvested at different stages of grain maturity and nutritive value of different fractions of the stover

The proportion of different morphological fractions of maize stover was assessed at three stages of grain maturity and nutritive value of the morphological fractions was evaluated based on chemical composition, in sacco dry matter (DM) degradability and in vitro gas production. Stem proportion of the stover increased by 20%, whereas the proportions of tassel and leaf blades decreased by 41.5 and 44%, respectively, as grain moisture content dropped from about 30–10%. The crude protein (CP) content was highest in leaf blade and tassel. Leaf blade had the lowest neutral detergent fibre (NDF), acid detergent fibre (ADF) and cellulose contents and the highest ash, ADF-ash and total proanthocyanidins (TPA) contents. On the other hand, CP, ash, ADF-ash and TPA contents were lowest and the NDF content was highest in husk. Stem had the highest ADF, lignin and cellulose contents. The overall in sacco DM degradability tended to be higher in leaf blades and lower in leaf sheaths than in the other morphological fractions. The washing loss was highest ( p < 0.05) in stem and lowest in leaf blade and husk. On the other hand, leaf blade had significantly higher ( p < 0.05) degradability of the water insoluble fraction than leaf sheath, stem and whole stover. The lag time was highest ( p < 0.05) in stem and lowest in leaf blades. The morphological fractions differed in the volume of gas produced in the following order: husk > whole stover > stem > leaf sheath > leaf blade > tassel. Stem and whole stover showed rapid gas production in the early stage of fermentation, although the gas production rate of stem started to decline earlier than that of the other morphological fractions. Gas production due to fermentation of insoluble feed components, which mostly occurred between 6 and 24 h of incubation, was highest in husk. In vitro gas production and in sacco DM degradability could not rank the morphological fractions in a similar order which could be due to the effect of protein fermentation on gas production. Gas production showed an inverse relationship with CP, ash, ADF-ash and TPA contents of the morphological fractions.

The effect of stage of maturity on yield and quality of maize grain and stover

Stage of maturity at the time of harvest is considered as one of the factors influencing the nutritive value of crop residues. Thus this study was carried out to assess the effect of harvesting maize at different stages of grain maturity on yield and quality of maize grain and stover. The maize crop was harvested at grain moisture content of 28–30, 20–23 and 10–12%, which were designated as Stages I, II and III, respectively. Grain yield, standardised to 12.5% moisture content, showed an increasing trend, whereas cob, stover, total crop residue and total biomass dry matter (DM) yield showed a decreasing trend with increasing stage of maturity ( p>0.05). The declining trend in stover yield with increased stage of maturity was due mainly to leaf loss. There was a significant decrease ( p<0.05) in crop residue–grain ratio and leaf–stem ratio and a significant increase in the harvest index and hectolitre weight of the grain as the grain moisture content decreased from about 30 to 10%. Maize stover harvested at Stage I had significantly higher ( p<0.05) ash content than those harvested at Stages II and III. The crude protein (CP) content was significantly lower, whereas the neutral detergent fibre and cellulose contents were higher ( p<0.05) in Stage III than in Stages I and II. There was a decreasing trend in in sacco DM degradability with increasing stage of maturity. The washing loss, potential degradability and effective DM degradability at 0.03 h −1 rumen outflow rate were higher ( p<0.05) in Stage I than in Stages II and III. The volume of gas produced after 3, 6, 12, 24, 48 and 72 h of incubation was higher ( p<0.05) in Stage I than in Stages II and III. The a value (the intercept of the gas production curve) and the gas production potential ( a+ b) were higher ( p<0.05) in Stage I than in Stage III. Reduction in the nutritive value of stover with increasing stage of maturity was characterised by reduction in CP contents and increasing concentration of fibrous constituents. These were reflections of changes in the morphological composition of stover and losses of nutrients within the morphological fractions with increasing stage of maturity.

Selection of diets by dual-purpose Mamber goats in Mediterranean woodland

The feeding behaviour of Mamber dairy goats grazing on Mediterranean woodland in the Upper Galilee mountains of Israel was studied throughout a year (1991/92). The percentages of crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL) and condensed tannins (CT) were determined in samples collected by hand to simulate the plant parts selected by the goats. Total feed intake was evaluated by using Cr-sesquioxide as an external marker to determine the amount of faeces excreted, and 48 h in sacco degradability to assess the digestibility of samples. Overall, more time was spent by goats in feeding on ligneous material (tree and shrub foliage) than herbaceous vegetation (60 and 40% of total feeding time, respectively, P&lt;0·05). The main ligneous species consumed by the goats were Quercus calliprinos, Sarcopoterium spinosum and Calicotome villosa (20, 13 and 7% of total grazing time, respectively). There was considerable variability in the 48 h dry matter (DM) in sacco degradability, and in the concentration of CP, NDF, ADF, ADL and CT, within and between seasons and plant species. Although requirements for nutrients varied according to the physiological stage of the goats, 48 h in sacco DM degradability and the concentration of non-ADF linked (available) CP, NDF, ADF, ADL and CT in the diet did not vary greatly: respective ranges were 45·0–49·4; 9–12·5; 44–53; 33–39; 12–17 and 3·5–4·7%. It is concluded that Mamber goats (i) may not select the best quality diet available, but may avoid wide variations in nutrient content of their diets throughout the year; and (ii) may not select a diet consistent with maximization of milk yield, but rather with optimization of body condition at the onset of the mating season.

Occurrence of digestive interactions in tree forage-based diets for sheep

The effect of browse level in the diet on the in vivo dry matter digestibility (DMD) in sheep and the DM degradation of peanut hay in the rumen of cattle-fed tree forage-based diets were investigated in order to detect the occurrence of digestive interactions between diet components. Selected browse species Acacia albida pods, Pithecellobium dulce, Adansonia digitata and Calotropis procera leaf samples were collected in the central regions of Senegal, sundried and stored in LNERV animal barns for in vivo trials. Classical in vivo balance trials were performed for each tree forage sample. The proportion of browse in the applied diet varied between 0 and 75% of DM. Regression and difference procedures were both tested to estimate the DMD of the browse component of the diet. DMD capacity in the rumen of three young Gobra bulls fed the browse-based diets was estimated by measurement of the in sacco dry matter degradation profile of a standard sample, peanut hay. For each sample, large variations were observed when the browse DMD was calculated by difference. Both total ration DMD and rumen DM degradation capacity were significantly ( p<0.001) influenced by browse level in the diet. However, non-linear response of total diet DMD to increasing levels of browse was observed only in A. digitata and P. dulce indicating occurrence of digestive interactions in those species. Rumen DM degradation capacity varied according to plant species which played a major role in the observed digestion profile. Results suggest that the digestion of tree forages-based diets may be influenced by digestive interactions but the large variations observed in plant species show their importance. Optimal DM degradation occurred at 15–30% of browse level in the diet for both A. albida and A. digitata while for P. dulce it was at 50%. Corresponding browse digestibility was of 50%, 47.1%, 51.3% and 60.7% DM for A. albida, A. digitata, P. dulce and C. procera respectively. Further work using the regression method in a wider range of browse species could help confirm between-species variations.

Nitrogen fractions and in sacco dry matter and crude protein degradability of fresh and frozen alfalfa

Second cut alfalfa was harvested at 163 g kg −1 DM content and processed fresh or after being frozen for 30 days at −18°C. Concentrations of ammonia– and free amino acid–N were clearly increased in frozen samples compared to the fresh crop. Freezing resulted in increased extent of initial dry matter and crude protein disappearance in sacco. Rumen degradability parameters significantly differed from those of the fresh forage with the soluble and potentially degradable fraction being the most affected. The effect of freezing on rumen degradability of alfalfa tended to disappear after 24 h of rumen incubation.

Edible forage production, chemical composition, rumen degradation and gas production characteristics of Calliandra calothyrsus (Messin) provenances in the humid tropics of West Africa

Two experiments evaluated variations in feed value among Calliandra calothyrsus provenances. In Experiment 1, edible forage production of four provenances were evaluated at Ibadan, southwestern Nigeria over a 2-year period in three seasons: main-wet (April–August), minor-wet (September–November) and dry (December–March). Forage samples from the main-wet and dry seasons were incubated for 6, 12, 48, 72 and 96 h in rumen-fistulated steers to estimate in sacco dry matter (DM) and nitrogen (N) degradation characteristics. In vitro gas production was estimated over 3, 6, 12, 24, 48, 72 and 96 h of incubation. In Experiment 2, DM degradation characteristics of 14 provenances of C. calothyrsus planted on an acid soil in Yaounde, Cameroon, were evaluated. Data were subjected to cluster analysis for grouping, and the 14 provenances were placed into four distinct cluster groups. Based on the potential extent of DM and, N degradation and gas production characteristics in Experiment 1, the four provenances of C. calothyrsus were classified into three forage quality groups: high (ILCA 16310), medium (ILCA 14891, ILCA 15166) and low (NFTA 896). In Experiment 2, using the extent of DM degradation as a forage quality index, C. calothyrsus provenances in clusters 3 and 4 (namely: 51/92, 11/91, 13/91, 45/92, 10/91, 15/91, 18/91, 134/91, 12/91, 62/92), were relatively higher in quality than their counterparts in clusters 1 and 2. The results suggested the existence of intra-species variation among the provenances, and confirmed earlier observations that forage quality of C. calothyrsus could be improved through provenance evaluation.

Degradability of Andean Range Forages in Llamas and Sheep

In sacco dry matter degradability (DMD) of the most commonly consumed range forages by llamas and sheep in the arid highlands of Bolivia was measured during the wet and dry seasons to determine if llamas exhibit a higher digestive ability than sheep. Results showed that degradability of low quality forages (DMD below 60% in sheep) was 20 to 30% higher for llamas than sheep, while no significant differences were found for highly digestible forages. There was a high correlation between DMD in llamas and sheep with a coefficient of determination of 0.96. Parameters of degradation curves indicated that llamas did not have higher microbial activity than sheep, since there was no consistent difference in degradation rates of the studied forages. Nonetheless, significantly higher potential degradability and effective degradability found in this study suggested that the longer retention time in the forestomach of llamas may be responsible for higher digestibility of poor quality forages.

The effects of supplementation with Gliricidia sepium or Leucaena leucocephala forage on intake, digestion and live-weight gains of Bos taurus × Bos indicus steers offered napier grass

AbstractTwo experiments were carried out to evaluate the effect of incremental levels of Gliricidia sepium (gliricidia) and Leucaena leucocephala (leucaena) on forage intake, diet apparent digestibility, microbial nitrogen supply and live-weight changes in cattle. In each experiment, 20 intact and five fistulated crossbred steers (Bos taurus × Bos indicus) were used. Napier grass basal diet was offered ad libitum alone or supplemented with 7·5, 15, 22·5, or 30 g dry matter (DM) per kg metabolic body weight (M075) gliricidia (experiment 1) or leucaena (experiment 2). In experiment 1, total DM intake increased but not significantly with gliricidia supplementation (5·2, 5·1, 5·2, 5·4, 5·7 (s.e.d. 0·21) kg/day) while intake of napier grass was depressed linearly (5·2, 4·7, 4·5, 4·3, 4·2 (s.e.d. 0·21) kg/day; P &lt; 0·05). In experiment 2, supplementation with leucaena increased the total DM intake linearly without depressing the intake of napier grass (5·2, 5·8, 6·2, 6·6, 6·7 (s.e.d. 0·31) kg/day; P &lt; 0001 and 5·2, 5·3, 5·3, 5·3, 5·0 (s.e.d. 0·21) kg/day respectively). Neither gliricidia nor leucaena supplementation affected the apparent digestibility of the diet or in sacco DM degradation characteristics of the forages. Rumen ammonia and live-weight gain were increased linearly (P &lt; 0·05) by supplementation from 130 to 215mg/l (experiment 1) and 75 to 113mg/l (experiment 2), from 306 to 478 g/day (experiment 1) and from 538 to 850 g/day (experiment 2), respectively. However, since the responses were linear, further experiments are required to quantify the responses to higher levels of these legume supplements.

Feed value of multipurpose fodder trees and shrubs in West Africa: edible forage production and nutritive value of Millettia thonningii and Albizia lebbeck

Millettia thonningii (Schum. & Thonn.) Bak., a nitrogen fixing shrub native to Africa and Albizia lebbeck Benth, were harvested at 0.50 m above ground level after one year of establishment to determine edible forage production. Harvests were made at the end of the main (April–August) and minor (September–November) wet, and dry (December–March) seasons for two years. Dry season edible forage samples were analyzed for concentrations of crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (NDF), acid detergent lignin (ADL), cellulose (CL), soluble phenolics (SOPH) and proanthocyanidins (PAs). In sacco dry matter (DM) and nitrogen (N) degradation and in vitro gas production (GP) characteristics were also determined on dry season edible forage samples. Edible forage production of M. thonningii was significantly lower than A. lebbeck during the wet seasons. Millettia thonningii had relatively lower CP and PAs, but higher NDF, ADF, ADL, CL and SOPH than A. lebbeck. In sacco DM and N degradation and in vitro GP parameters of M. thonningii were significantly lower than A. lebbeck. Parameters of in sacco DM degradation and in vitro GP were highly correlated. Millettia thonningii appeared to be of lower feed value than A. lebbeck based on edible forage production, chemical composition, in sacco DM and N degradation and in vitro GP characteristics.

Influence of Rumen Protected Fat on Rumen Fermentation,in SaccoDry Matter Degradability and Apparent Digestibility in Sheep

Abstract Flachowsky, G., Wirth, R., Mockel, P. and Schneider, A. 1995. Influence of rumen protected fat on rumen fermentation, in sacco dry matter degradability and apparent digestibility in sheep. J. Appl. Anim. Res., 8: 71–84. Three rumen fistulated sheep were fed on a ration consisting of 800 g artificially dried ryegrass, 400 g ground barley and 15 g mineral-vitamin-premix daily. In the following periods grass and barley were replaced by 60, 120 or 240 g (5, 10 or 20% of basal diet) of rumen protected fat. In each feeding period (26 days) samples of rumen fluid were taken via fistula three hours after morning feeding. For measuring dry matter degradability (DMD) ryegrass, alfalfa hay, wheat straw and rumen protected fat were placed in nylon bags and incubated for 0 (washing loss), 6, 12, 24 48 and 72 h in the rumen. Apparent digestibility of all four rations was measured by collection of faeces over five days. Fat supplementation did not significantly influence rumen pH and volatile fatty acids in rum...