Leaf Digestibility Research Articles

On the Digestibility of Mulberry Leaf Fed to Bombyx mori Larvae

On the Digestibility of Mulberry Leaf Fed to Bombyx mori Larvae

Evaluation of Nutrient Digestibility and Metabolizable Energy of Yeast-Fermented Acacia mangium Leaf by Japanese Quails

The nutrient digestibility and the metabolizable energy (AME) of Acacia mangium leaf (AM) and yeast-fermented AM (YFAM) by Japanese quails were investigated. Fifty-four of 4-weeks-old Japanese quails were divided into 3 groups with six replications of three quails. Each quail was randomly fed with an experimental diet composed of dextrose (protein-free diet for determining endogenous excretion) 40 % AM and 40% YFAM. The quails were raised individually in a metabolic cage, where feed and water were provided ad-libitum. Both feed intake and feces weight were recorded. Experimental diets and excreta were sampled and subjected to proximate analysis for gross energy. The results of nutrient composition indicated that the fermentation AM with yeast highly significantly increased (P<0.01) dry matter (DM), ash, and nitrogen-free extractives (NFE) content but decreased (P<0.01) crude protein (CP), crude fiber (CF), and gross energy (GE) content. In addition, the birds fed dietary YFAM compared with AM showed significantly increased (P≤0.01) DM, organic matter (OM), CP, and GE digestibility but decreased (P≤0.01) EE and CF digestibility. The protein utilization of birds fed dietary YFAM showed significantly greater (P≤0.01) FI, protein retained, protein intake, net protein utilization (NPU), and AME than those fed dietary AM. In conclusion, the fermentation of AMLM with yeast improved nutrient composition and enhanced the digestibility of nutrients, protein utilization, and AME of AMLM in Japanese quail.

PSVII-13 Evaluation of Ginkgo Leaf as a Feed for Ruminants by Using in Vitro gas Production Technique

Abstract The objective of this study was to examine the fermentation characteristics of ginkgo leaf compared with traditional feeds, rice straw, alfalfa and soybean meal, by using in vitro gas production technique. Three ruminal cannulated Chinese Holstein dairy cows were fed a total mixed ration. Rumen fluid was collected via from a ruminal cannula before feeding and then filtered through four layers of cheesecloth. Samples (220 mg air-dried) of rice straw, alfalfa, soybean meal and ginkgo leaf were placed in each glass bottle (150 mL), and 30 mL mixed solution with rumen fluid and a buffer solution (1:2 v/v). Three replicates of each sample were incubated in shaking bath at 39 °C for 48 h. The gas production was measured at 0, 3, 6, 9, 12, 24 and 48 h, respectively. The gas production data were fitted to the non-linear model Y = A + B (1 – e-CT). The results demonstrated that the ginkgo leaf had significantly greater in vitro gas production compared with the other feeds at each observation time. The amount of gas production from the immediately soluble fraction (A) of the four test feeds were all positive. The gas production from the insoluble fraction (B) of alfalfa was least at 43.82 mL and ginkgo leaf showed significantly greater B values than alfalfa. The gas production rate (C) was significantly greater for ginkgo leaf than those C values for rice straw and soybean meal. The in vitro dry matter and crude protein digestibility (%) of ginkgo leaf were 99.6 and 98.7, respectively, which were significantly greater than those of soybean meal. The total volatile fatty acid production of ginkgo leaf was significantly greater than that of rice straw, and the ammonia concentration of ginkgo leaf decreased significantly. It indicated that ginkgo leaf could be used as a protein source feed for ruminants.

Circum‐Arctic distribution of chemical anti‐herbivore compounds suggests biome‐wide trade‐off in defence strategies in Arctic shrubs

Spatial variation in plant chemical defence towards herbivores can help us understand variation in herbivore top–down control of shrubs in the Arctic and possibly also shrub responses to global warming. Less defended, non‐resinous shrubs could be more influenced by herbivores than more defended, resinous shrubs. However, sparse field measurements limit our current understanding of how much of the circum‐Arctic variation in defence compounds is explained by taxa or defence functional groups (resinous/non‐resinous). We measured circum‐Arctic chemical defence and leaf digestibility in resinous (Betula glandulosa, B. nana ssp. exilis) and non‐resinous (B. nana ssp. nana, B. pumila) shrub birches to see how they vary among and within taxa and functional groups. Using liquid chromatography–mass spectrometry (LC–MS) metabolomic analyses and in vitro leaf digestibility via incubation in cattle rumen fluid, we analysed defence composition and leaf digestibility in 128 samples from 44 tundra locations.We found biogeographical patterns in anti‐herbivore defence where mean leaf triterpene concentrations and twig resin gland density were greater in resinous taxa and mean concentrations of condensing tannins were greater in non‐resinous taxa. This indicates a biome‐wide trade‐off between triterpene‐ or tannin‐dominated defences. However, we also found variations in chemical defence composition and resin gland density both within and among functional groups (resinous/non‐resinous) and taxa, suggesting these categorisations only partly predict chemical herbivore defence. Complex tannins were the only defence compounds negatively related to in vitro digestibility, identifying this previously neglected tannin group as having a potential key role in birch anti‐herbivore defence.We conclude that circum‐Arctic variation in birch anti‐herbivore defence can be partly derived from biogeographical distributions of birch taxa, although our detailed mapping of plant defence provides more information on this variation and can be used for better predictions of herbivore effects on Arctic vegetation.

Effect of microbial fermentation on nutritional and antinutritional contents of cassava leaf

AbstractCassava leaves serves as a source of alternative proteins for people in developing countries who could not easily access the available protein sources. However, its use is limited by the presence of toxic compounds, particularly cyanogenic glycosides. Thus, use of appropriate processing technique is indispensable to reduce the toxic compounds to a safer limit before utilization of cassava leaf. The objective of this study was therefore to evaluate the effect of Lactobacillus plantarum and Saccharomyces cerevisiae strains, and their co‐culture on nutritional contents and antinutritional factors of cassava leaf during fermentation. A 4 × 5 factorial experimental design was used to determine the effect of fermentation setups and time on chemical composition, antinutritional contents, in vitro protein digestibility and mineral contents of cassava leaf. During 48 h of fermentation, a significant change (p < 0.05) in moisture, protein, fiber, fat, and ash contents were observed. Protein content was improved by 34.91%, while in vitro digestibility of protein was improved by 28.07% during 48 h of L. plantarum fermentation. Cyanide, oxalate, tannin, and phytate contents were decreased significantly (p < 0.05) for all fermentation setups. The highest reduction in cyanide (97.17%) and oxalate (86.44%) was achieved under L. plantarum fermentation. The highest reduction in tannin (93.25%) and phytate (91.11%) was achieved under co‐culture fermentation of cassava leaf. A significant (p < 0.05) reduction of mineral contents except iron was observed during 48 h of fermentation. A significant (p < 0.0001) strong negative correlation was found between protein with cyanide (−0.8164), oxalate (−0.7991), phytate (−0.7851), and tannin (−0.6906). In vitro digestibility of protein also showed a strong significant (p < 0.0001) negative correlation with phytate (−0.9628), oxalate (−0.9407), cyanide (−0.9305), and tannin (−0.8493). Application of L. plantarum and S. cerevisiae in cassava leaf fermentation showed significant improvement of nutritional qualities by reducing the antinutritional factors and toxic compounds. Fermentation of cassava leaf using these strains ascertain utilization of cassava leaf for human consumption to tackle protein energy malnutrition.

Do trait responses to simulated browsing in Quercus robur saplings affect their attractiveness to Capreolus capreolus the following year?

With the rise of large herbivore populations in most northern hemisphere forests, browsing is becoming an increasingly important driver of forest regeneration dynamics. Among other processes affecting the regeneration, the concept of plant-herbivore feedback loops holds that browsed saplings are more subject to subsequent herbivory. This phenomenon is interpreted as a consequence of compensatory growth following browsing since fast growth is generally associated with higher digestibility and lower defense against herbivores. However, studies linking browsing-induced trait variations to subsequent attractiveness to herbivores are still lacking, especially in the forest context. In this study, we experimentally examine the existence of a feedback loop between oak ( Quercus robur L.) and roe deer ( Capreolus capreolus ) and investigate its underlying morphological and chemical traits. We simulated single and repeated roe deer browsing on nursery-grown oak saplings and measured the changes in sapling height growth, lateral branching, leaf traits and winter shoot traits over two years. We conducted winter feeding trials with tame roe deer one year after the first treatment to test the effect of simulated browsing on sapling attractiveness. Simulated browsing reduced sapling height growth but had no effect on branching. Simulated browsing had no effect on leaf traits after half a year, but decreased the phenolic content and increased the fiber content of winter shoots the following winter. Contrary to our predictions, roe deer preferentially browsed control saplings over saplings previously browsed. After two years, repeated browsing promoted fast carbon acquisition leaf traits (high chlorophyll, high specific leaf area and low fiber content), reduced leaf phenolic content and increased leaf digestibility. We showed that a reduction in 1-year-old oak sapling height growth following browsing, combined with increased structural defense at the expense of chemical defense in winter shoots the following winter, was correlated with reduced browsing pressure, thereby challenging the feedback loop hypothesis. However, we also demonstrated that repeated browsing promoted fast carbon acquisition leaf traits in 2.5-year-old saplings, which tend to support the existence of a feedback loop on older and more intensively browsed saplings. As such, our study provides empirical evidence that morphological and physiological trait responses to browsing influence oak sapling attractiveness, but that the direction and magnitude of this effect depend on the ontogenic stage of the sapling and on the number of browsing events. • We examine the morphological and chemical response of oak saplings to browsing. • Browsing reduces sapling height growth and modifies shoots chemical composition. • We show with feeding trials that roe deer prefers unbrowsed saplings. • Oak trait responses to browsing decrease the probability of subsequent herbivory.

Future warming will change the chemical composition and leaf blade structure of tropical C3 and C4 forage species depending on soil moisture levels

Temperature and soil moisture strongly affect the nutritional value and digestibility of forage plants through changes in leaf chemical composition or the proportion of leaf blade tissues. In this study, we aimed to evaluate leaf blade anatomical modifications of two tropical forage species, Stylosanthes capitata (C3) and Megathyrsus maximus (C4) under warmed conditions (+2 °C) at well-watered and rainfed conditions and investigate the interactions between leaf anatomical alterations, leaf chemical composition, and leaf digestibility. Experiments were conducted under field conditions using a Temperature-free air-controlled enhancement (T-FACE) system. We observed that plants under elevated temperature produced leaves with smaller stomata and thinner mesophyll tissue and reduced total leaf thickness, potentially impacting gas exchange. On the other hand, reduced soil moisture increased stomatal density and thickness of the adaxial epidermis. In both species, leaf fibrous fractions concentration increased under warmed and non-irrigated conditions, while crude protein concentration and digestibility decreased. However, leaf digestibility was associated with leaf chemical composition rather than the proportion of different leaf blade tissues. We concluded that although both species developed leaf anatomical modifications to acclimate under future warming conditions, leaf nutritional value and digestibility will be reduced, potentially impacting future livestock production and methane emissions by ruminants.

Effect of Plant Spacing on Agronomic Performance and Fodder Quality of Four Tepary Bean (Phaseolus acutifolius A. Gray) Cultivars

Tepary bean is gaining interest around the world as a dryland field crop. A two-year field experiment was conducted to determine the effect of plant spacing on the agronomic performance and fodder quality of the crop. A split-plot design was used with three replications, four cultivars (GK010, GK011, GK012, and Motsumi) were assigned to main plots, while subplots were three intrarow plant spacing (10 cm, 20 cm, and 30 cm). Four agronomic variables and eight chemical compositions, including in vitro dry matter digestibility (IVDMD) of husk, stem, and leaf, were measured. Spacing significantly ( P < 0.05 ) influenced plant biomass, pod yield, harvest index, and seed yield, while cultivar affected only pod yield and seed yield. Plant biomass increased with plant spacing where 10 cm produced 936 kg/ha; 20 cm, 750 kg/ha; and 30 cm, 611 kg/ha for 2015–2016 while 10, 20, and 30 cm were observed for 1568 kg/ha, 1135 kg/ha, and 889 kg/ha, respectively, in 2016–2017 season. These trends are attributed to the higher plant population in the narrow row spacing. GK012 consistently outperformed other cultivars for plant biomass, pod yield, and seed yield and has a potential for further selection. Fodder nutritive qualities were not affected by cultivar, while spacing only influenced IVDMD. The three plant parts were significantly ( P < 0.05 ) different for all the nutritive qualities. Leaves had significantly ( P < 0.05 ) lower values of ADF, CF, and NDF compared to those of stem and husk an indication of relatively higher digestibility of the leaf. Acid detergent fiber (40%), neutral detergent fiber (53.65%), crude fiber (35.45%), ash content (12.29%), dry matter (93.09%), and IVDMD (70.66%) were recorded. This study revealed that tepary bean forage has good nutritional content, except for the low phosphorus level. For higher agronomic performance, tepary cultivars should be planted at a spacing of 10 cm without compromising forage quality.

Feeding Sheep Cobalt and Oregano Essential Oil Alone or in Combination on Ruminal Nutrient Digestibility, Fermentation, and Fiber Digestion Combined With Scanning Electron Microscopy.

The feeding of Co lactate (Co), an essential oil blend (EO; oregano), or a combination of Co and EO (EOC) may improve nutrient digestion of corn silage-based rations. In four separate studies, Co, EO, or EOC was fed at 0, 4, and 7 g/days to nine rumen fistulated rams arranged in a replicated 3 × 3 Latin square design. The fourth study evaluated the carrier at 0, 4, and 7 g/day. In each ram, fresh ensiled corn silage, leaf, and husk were placed in individual nylon bags inserted through the ruminal cannula and removed after 48 h. Rams fed increasing carrier rates demonstrated similar (P > 0.10) nutrient digestibilities and ruminal pH and volatile fatty acid concentrations. Feeding Co at 4 and 7 g/day increased (P < 0.05) digestibility of DM (59.4, 63.9, and 62.4% for 0, 4, and 7 g/day, respectively), NDF (59.4, 63.9, and 62.4%), and hemicellulose (HC; 56.2, 63.6, and 65.9%) compared with rams fed 0 g/day, while CP digestibility (46.4, 49.9, and 57.8%) was improved (P < 0.05) in rams fed 7 g/day compared with those fed 0 and 4 g/day. Rams fed 4 g/day EO digested greater (P < 0.05) HC (64.1, 71.4, and 69.1%) than rams fed 0 g/day, while rams fed 7 g/day were intermediate and similar (P > 0.10). Rams fed the EOC combination at 4 and 7 g/day demonstrated greater (P < 0.05) digestibilities of DM (57.7, 60.0, and 60.0%), NDF (21.4, 28.8, and 27.7%), and ADF (24.3, 33.3, and 34.4%) than rams fed 0 g/day. The SEM and SM techniques visually demonstrated minor evidence of husk and leaf digestibility in rams across the three experiments when fed 0 g/day of Co, EO, or EOC; rams fed 4 g/day of Co, EO, or EOC exhibited varying visual signs of leaf digestion with some palisade tissue, spongy tissue, and whole vein structure remaining, while in rams fed 7 g/day, only the vein structure remained. Results demonstrated that feeding Co, EO, or EOC at 4 or 7 g/day enhanced ruminal nutrient digestion and fermentation parameters, which was visually confirmed via SEM and SM.

CELL-WALL COMPOSITION AND DIGESTIBILITY OF FIVE NATIVE SHRUBS OF THE TAMAULIPAN THORNSCRUB IN NORTHEASTERN MEXICO

&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Many trees and shrubs from different parts of the world have forage potential, because they are inexpensive local products used for small ruminants as feed resource, some of these native shrubs are currently already an important fodder resources in arid and semi-arid regions of Northeastern México. &lt;strong&gt;Objective:&lt;/strong&gt; The aim of this study was to determine the cell-wall composition and &lt;em&gt;in vitro&lt;/em&gt; leaf digestibility of five shrub species: &lt;em&gt;Celtis pallida&lt;/em&gt;, &lt;em&gt;Croton suaveolens&lt;/em&gt;, &lt;em&gt;Forestiera angustifolia&lt;/em&gt;, &lt;em&gt;Guaiacum angustifolium&lt;/em&gt; and &lt;em&gt;Parkinsonia aculeata&lt;/em&gt;. &lt;strong&gt;Methodology: &lt;/strong&gt;Plant material was collected monthly from July 2018 to June 2019 at two sampling sites in Nuevo León, México: Linares and Los Ramones Counties. &lt;em&gt;In vitro&lt;/em&gt; dry matter digestibility (IVDMD) was calculated using the Daisy&lt;sup&gt;II&lt;/sup&gt; incubator. &lt;strong&gt;Results: &lt;/strong&gt;Non-structural carbohydrates (NSC) (total mean = 22.4% dry matter) varied significantly among species, sites, and months (p&amp;lt;0.001, p&amp;lt;0.05 and p&amp;lt;0.001, respectively). Conversely, neither acid detergent lignin (ADL) (8.4%), crude protein (CP) (21.9%), cellulose (12.5%), hemicellulose (20.8%), nor IVDMD (75.5%) varied significantly between sites. In general, NSC values were higher in Linares. The highest and lowest IVDMD values as per the Daisy&lt;sup&gt;II&lt;/sup&gt; incubator were recorded in March and September, respectively. &lt;em&gt;C&lt;/em&gt;. &lt;em&gt;pallida&lt;/em&gt; showed the highest IVDMD associated with a high hemicellulose and low ADL values, whereas &lt;em&gt;P&lt;/em&gt;. &lt;em&gt;aculeata&lt;/em&gt; showed a lower IVDMD value and high cellulose content. &lt;strong&gt;Implications: &lt;/strong&gt;All species maintained considerably high levels of digestibility, which might indicate an availability of high CP levels for consumption by ruminants in the semi-arid regions of northeastern México. &lt;strong&gt;Conclusion:&lt;/strong&gt; It is concluded that the species under study can be considered as emergency feed resources for small ruminants throughout the year.&lt;/p&gt;

Responses of Lotus corniculatus to environmental change 3: The sensitivity of phenolic accumulation to growth temperature and light intensity and effects on tissue digestibility

Growth temperature and light intensity are major drivers of phenolic accumulation in Lotus corniculatus resulting in major changes in carbon partitioning which significantly affects tissue digestibility and forage quality. The response of plant growth, phenolic accumulation and tissue digestibility to light and temperature was determined in clonal plants of three genotypes of Lotus corniculatus (birdsfoot trefoil) cv Leo, with low, intermediate or high levels of proanthocyanidins (condensed tannins). Plants were grown from 10 °C to 30 °C, or at light intensities from 20 to 500 µm m-2 s-1. Plants grown at 25 °C had the highest growth rate and highest digestibility, whereas the maximum tannin concentration was found in plants grown at 15 °C. Approximately linear increases in leaf flavonol glycoside levels were found with increasing growth temperature in the low tannin genotype. Tannin hydroxylation increased with increasing growth temperature but decreased with increasing light intensity. The major leaf flavonols were kaempferol glycosides of which kaempferol-3-glucoside and kaempferol-3,7-dirhamnoside were the major components. Increases in both tannin and total flavonol concentrations in leaves were linearly related to light intensity and were preceded by a specific increase in the transcript level of a non-legume type chalcone isomerase. Changes in growth temperature and light intensity, therefore, result in major changes in the partitioning of carbon into phenolics, which significantly affects tissue digestibility and nutritional quality with a high correlation between tannin concentration and leaf digestibility.

Contributions at Capitalization Study on Chemical Content from Mulberry Tree Leave by Bombyx Mori Larvae

In order to assess how efficient is the use of mulberry leaf by the Bombyx mori Baneasa Super larvae hybrid, some determinations were made regarding the nutritional value and digestibility of the worm leaf administered as food, during a series of summer growth. The results showed that ongoing vegetation and growth process of this hybrid, the Mulberry leaves suffer an aging phenomenon, revealed by diminishing its chemical composition quality. According to this, most of the nutritional substances from mulberry leaves, except cellulose, manifest a continuous decline during the growth period. The digestibility of these nutritional components registered a value of 56.41%, the crude energy value was 4209 kcal/kg dry substance, and digestive energy was 2173 kcal/kg (DS), while the metabolic energy was 2044-2007 kcal/kg (DS). The efficiency of converting ingestion into silk had a value of 9.30% and the digestion was 15.76%.

Contributions at Capitalization Study on Chemical Content from Mulberry Tree Leave by Bombyx Mori Larvae

In order to assess how efficient is the use of mulberry leaf by the Bombyx mori Baneasa Super larvae hybrid, some determinations were made regarding the nutritional value and digestibility of the worm leaf administered as food, during a series of summer growth. The results showed that ongoing vegetation and growth process of this hybrid, the Mulberry leaves suffer an aging phenomenon, revealed by diminishing its chemical composition quality. According to this, most of the nutritional substances from mulberry leaves, except cellulose, manifest a continuous decline during the growth period. The digestibility of these nutritional components registered a value of 56.41%, the crude energy value was 4209 kcal/kg dry substance, and digestive energy was 2173 kcal/kg (DS), while the metabolic energy was 2044-2007 kcal/kg (DS). The efficiency of converting ingestion into silk had a value of 9.30% and the digestion was 15.76%. Keywords: leaves, mulberry, larvae, energy, use

Animal performance, production, and quality of Tanzania grass fertilized with nitrogen

This study aimed to assess forage production, animal performance, and the chemical composition of Tanzania grass pasture fertilized with 50, 100, 200, and 400 kg ha-1 of nitrogen. The variables analyzed were: leaf mass, daily accumulation rate, leaf/stem ratio, average daily gain, stocking rate, live weight gain per unit of area crude protein, neutral detergent fiber, and in vitro dry matter digestibility of leaves. The pasture management maintained the pasture height at 50 cm by using a continuous grazing method with the adjustment of stocking rate. The experimental design was a randomized block with three replicates. The leaf mass increased linearly in response to nitrogen, with an increase of 1003 kg (34%) observed between a nitrogen content of 50 and 400 kg ha-1. Nitrogen did not affect the average daily gain, but increased the stocking rate and live weight gain ha-1. The value of crude protein and neutral detergent fiber were higher with increased nitrogen levels, whereas the leaf digestibility did not affect nitrogen use. The comparison of 50 and 400 kg ha-1 levels indicated that there was an average increase of 19.2% in the leaf crude protein. The increased application of nitrogen fertilizer in Tanzania grass improved the chemical composition and animal performance; with regard to studied variables, the dose of 200 kg ha-1 resulted in the greatest improvement.

Nutrient Composition and Digestibility of Taro Leaf in the Diets of Chicken and Effects on the Meat Quality

Nutrient Composition and Digestibility of Taro Leaf in the Diets of Chicken and Effects on the Meat Quality

Dual-Use Bioenergy-Livestock Feed Potential of Giant Miscanthus, Giant Reed, and Miscane

High yielding perennial grasses could integrate bioenergy-livestock operations, thereby, offsetting diversions of cropland to lignocellulosic crops, but research is needed to determine chemical composition and digestibility of leaf and stem fractions that might affect downstream reside uses. The objective of this study was to compare feedstock quality of leaf and stem tissues of dedicated bioenergy feedstocks: giant miscanthus (Miscanthus × giganteus), giant reed (Arundo donax), and miscane (Saccharum hybrid × Miscanthus spp.) when grown with or without supplemental irrigation on an upland site. Three species were space-planted on a silt loam soil in March 2007 and harvested prior to the first freeze in plant-cane, first ratoon, and second-ratoon crops for three years. Giant miscanthus leaf tissue had greatest acid detergent lignin and cellulose, and lowest concentrations of nitrogen (N) and total nonstructural carbohydrates (TNC) in ratoon crops. Giant reed leaf tissue had greatest concentrations of in vitro digestible dry matter (IVDMD), TNC, and N (P ≤ 0.05). Conversely, miscane stem tissue had greatest concentrations of IVDMD, TNC, hemicellulose, and low dry matter and combustible energy (P ≤ 0.05). Results suggest all species’ residue has positive feedstock attributes for thermochemical bioenergy conversion, and albeit giant miscanthus has very little potential value as fodder. Miscane stem and giant reed leaf tissue have potential value as livestock feed, although giant reed is not currently recommended for planting. Further research is needed on dietary composition, acceptability, voluntary intake, and live weight gain before any of these species are recommended as livestock feed sources.

Interactive Effects of Trees and Nitrogen Supply on the Agronomic Characteristics of Warm‐Climate Grasses

Plant adaptations to cope with shade may vary according to the degree of shade tolerance and nutrient availability for each species. Studies of different understory species and their responses to combined shade and N effects are important to identify ways to optimize the quantity and quality of forage production. Our objective was to measure the dry matter yield (DMY) and nutritive value of six C4 grasses grown in two systems (full sunlight [FS] vs. a naturally shaded system composed of Eucalyptus dunnii Maiden trees) with two N levels (0 vs. 300 kg N ha−1yr−1) using the same target sward conditions (i.e., 50% depletion of the canopy height set by 95% light interception). Over 3 yr, the decreases in DMY under shade compared with FS ranged from 7% [Urochloa brizantha (Hochst. ex A. Rich) R.D. Webster] to 56% (Cynodon spp.) in fertilized treatments and between 11% (Paspalum notatum Fluegge) to 46% (Cynodon spp.) in treatments without N. The N effect was more important to the nutritive value of the forage than the shade effect, particularly for crude protein (CP, +46 g kg−1 with N supply), acid detergent fiber (ADF, –46 g kg−1) and leaf proportion (+11.2%). However, most of the species displayed higher leaf digestibility under shade due to decreases in ADF. Even with intense shading (light approximately 48% of unshaded), the digestible DMY and CP yield under trees were, on average, 70 and 71% of the 6.8 and 1.4 t ha−1 recorded in FS, respectively.Core Ideas The study identifies C4 species for the optimization of forage production under trees. Nitrogen and shade have combined effects on forage production and nutritive value. Limitations and benefits of integrated crop–livestock systems with trees. Shade effects on nutritive value occur at the leaf level and of the total biomass harvested.

The variation in morphology of perennial ryegrass cultivars throughout the grazing season and effects on organic matter digestibility

AbstractThe grass plant comprises leaf, pseudostem, true stem (including inflorescence) and dead material. These components differ in digestibility, and variations in their relative proportions can affect sward quality. The objective of this study was to determine the change in the proportion and organic matter digestibility (OMD) of leaf, pseudostem, true stem and dead components of four perennial ryegrass cultivars (two tetraploids: Astonenergy and Bealey and two diploids: Abermagic and Spelga) throughout a grazing season. The DM proportions and in vitro OMD of leaf, pseudostem, true stem and dead in all cultivars were determined during ten grazing rotations between May 2011 and March 2012. There was an interaction between rotation and cultivar for leaf, pseudostem, true stem and dead proportions. In May and June, Astonenergy had the highest leaf and lowest true stem proportion (P &lt; 0·05). From July onwards, there was no difference in leaf or true stem proportion between cultivars. Bealey had the highest annual mean OMD (752 g kg−1) and Spelga the lowest (696 g kg−1; P &lt; 0·05). The OMD followed the order leaf &gt; pseudostem &gt; true stem &gt; dead. Bealey had the highest combined leaf and pseudostem proportion 0·92, which explains why it had the highest OMD. In this study, the tetraploid cultivars had the highest leaf and pseudostem proportion and OMD. For accurate descriptions of a sward in grazing studies and to accurately determine sward morphological composition, pseudostem should be separated from true stem, particularly during the reproductive stage when true stem is present.

Bromatological evaluation of eleven corn cultivars harvested at two cutting heights

The objective of this study was to evaluate the chemical composition and dry matter in vitro digestibility of stem, leaf, straw, cob and kernel fractions of eleven corn (Zea mays) cultivars, harvested at two cutting heights. The experiment was designed as randomized blocks, with three replicates, in a 2 × 11 factorial arrangement (eleven cultivars and two cutting heights). The corn cultivars evaluated were D 766, D 657, D 1000, P 3021, P 3041, C 805, C 333, AG 5011, FOR 01, CO 9621 and BR 205, harvested at a low cutting height (5 cm above ground) and a high cutting height (5 cm below the first ear insertion). Cutting height influenced the dry matter content of the stem fraction, which was lower (23.95%) in plants harvested at the low, than in plants harvested at the high cutting height (26.28%). The kernel fraction had the highest dry matter in vitro digestibility (85.13%), while cultivars did not differ between each other. Cob and straw were the fractions with the highest level of neutral detergent fiber (80.74 and 79.77%, respectively) and the lowest level of crude protein (3.84% and 3.69%, respectively). The leaf fraction had the highest crude protein content, both for plants of low and high cuttings (15.55% and 16.20%, respectively). The increase in the plant cutting height enhanced the dry matter content and dry matter in vitro digestibility of stem fraction, but did not affect the DM content of the leaf fraction.

Efek Suplementasi Daun Ubi Kayu terhadap Kecernaan Daun Sawit Amoniasi secara In Vitro

The purpose of this study was to obtain the level of supplementation of cassava leaves as a source of branched chain amino acids in improving nutrients digestibility of ammoniation palm leaf, and characteristics of rumen fluid ( in-vitro). The experiment was designed by using randomized block design with 6 treatments of supplementation of cassava leaf (A = 0% as control, B = 5%, C = 10%, D = 15%, E = 20% and F = 25% of dry matter) with 4 replications. Parameters were: 1) Digestibility of nutrients (dry matter, organic matter, crude protein) 2) Digestibility of fiber fractions (NDF, ADF, cellulose and hemicellulose) and 3) Characteristics of rumen fluid (pH, NH3, and VFA) by in- vitro. The results showed cassava leaves supplementation significantly (P &lt;0.05) increased the in-vitro digestibility of palm leaves ammoniation. The highest dry matter digestibility obtained at cassava leaf 5% (24.09%) in comparing controls (45.49% vs. 56.45%), and ADF digestibility increased by 36.91% compared to controls (37.25% vs. 51.00%). Cassava leaves maintained rumen fluid characteristics for microbial rumen growth and activities. It concluded, the level of supplementation cassava leaves as a source of the best branched chain amino acids in palm leaf ammoniation was 5%.