Herbage Quality Research Articles

Ecosystem services under different grazing intensities in typical grasslands in Inner Mongolia and their relationships

Grazing, as the main land use of grasslands, is a key factor affecting the supply of ecosystem services11ES, ecosystem service; GI, grazing intensity; CK, control check; LG, light grazing; MG, moderate grazing; HG, heavy grazing; BI, biodiversity; HI, herbage intake; CP, crude protein content; SOCD, soil organic carbon density; SMN, soil mineralization nitrogen; AB, aboveground biomass; BB, belowground biomass; LB, litter biomass; TES, total ecosystem services; SSU, standard sheep units. (ESs) as well as the relationships between ESs. Using four grazing intensities, including control check, light grazing, moderate grazing, and heavy grazing, this paper quantified eight key ESs, including biodiversity, herbage intake, herbage quality (herbage crude protein content), climate regulation (soil organic carbon density), soil mineralization nitrogen, soil conservation (aboveground biomass), wind prevention and sand fixation (belowground biomass), and soil erosion prevention(litter biomass), in typical grassland areas of Inner Mongolia. Structural equation models were used to illustrate the impact of grazing on ESs through biodiversity, and the root mean square error was used to quantify the level of trade-offs for ES pairs. The results of this study indicated that grazing intensity (GI) significantly affected all ESs (p < 0.05), except for soil organic carbon density and soil mineralization nitrogen. As GI increased, provisioning services increased, while most regulating services decreased, and there was a general trade-off relationship between regulating services and other ones. In order to realize the maximum ESs benefit and the minimum trade-offs for ES pairs, the optimal grazing intensity for typical grasslands of Inner Mongolia should be between 170 (standard sheep units) SSU · d · hm−2 · y−1 and 340 SSU · d · hm−2 · y−1. The results of this study provide a decision-making foundation for grassland grazing management policies for the sustainable development of Inner Mongolian grasslands.

Pasture legumes differ in herbage production and quality throughout spring, impacting their potential role in fodder conservation and animal production

AbstractThis study reports on the herbage production and quality of a range of pasture legume species during spring, at three sites with moderate to strongly acidic soils in southern NSW, Australia. These data have enabled prediction of livestock production when legumes are conserved as silage or hay. Total herbage production, its timing and quality differed significantly between species, which generally was not predicted by the traditional metric of time to flowering. Trifolium incarnatum L., T. michelianum L., Biserrula pelecinus L., Ornithopus sativus Brot. and Hedysarum coronarium L. all maintained growth rates exceeding 200 kg DM/ha/d for 4 weeks over spring, while T. vesiculosum Savi. maintained this for 6 weeks, with a peak growth rate of 561 kg DM/ha/d. Herbage quality of all species declined over time and was greatest in species with a rapid increase in stem‐to‐leaf ratio or with weak stems, resulting in lodging. The modelling inferred that maximizing potential livestock production via fodder conservation required earlier cutting. Only the indeterminate species B. pelecinus and Ornithopus spp. increased potential liveweight gain per hectare through delayed harvesting from (probable) silage to hay‐making time.

Impacts of cutting frequency and position to tree line on herbage accumulation in silvopastoral grassland reveal potential for grassland conservation based on land use and cover information

AbstractIn agricultural grassland, high herbage utilisation efficiency (HEFF), which is the proportion of gross live‐green herbage production that is utilised before entering senescence, is ensured by frequent defoliation. The decision upon which defoliation frequency to apply depends on the farming intensity. Assuming a reduced total herbage accumulation near trees in silvopastoral systems, frequent defoliations with high HEFF become less worthwhile—at least in specific spatial configurations. This makes an extensive management near trees an interesting option because it promotes other grassland‐related ecosystem services such as biodiversity. The present study first analysed the interaction between defoliation frequency and position to trees on the total, dead and live herbage accumulation and the HEFF at two silvopastoral sites with short‐rotation coppices in Germany. In addition, the total grassland–tree interface in Germany was assessed from land use and land cover maps of Germany based on satellite data to approximate the potential of grassland extensification near trees. The total herbage accumulation near trees declined by up to 41% but the HEFF was not affected by the position. Consequently, any intensification is not paid‐off by adequate productivity and herbage quality in terms of HEFF and tree‐related losses in herbage accumulation are expected up to a distance of 4.5–6 m. Applying a 4.5 m border on satellite data, we found that up to 4.4% (approximately 2200 km2) of the total grassland area in Germany is at a tree interface and potentially suitable for extensification. These findings indicate substantial potential for biodiversity conservation in grasslands with low trade‐off for high‐quality yield.

Selection for resistance to fungal diseases and other desirable traits in kikuyu grass (&lt;i&gt;Cenchrus clandestinus&lt;/i&gt;)

While kikuyu (Cenchrus clandestinus) is an important grass for dairy and beef production in the subtropical region of Australia and the world, the most common cultivar, Whittet, is seriously affected by the fungal diseases, kikuyu yellows (Verrucalvus flavofaciens) and black spot (Bipolaris spp.). Thus resistance to these diseases is a priority in selecting a better kikuyu cultivar, along with higher herbage quality and yield and better winter growth. A study was conducted to identify suitable candidates from kikuyu ecotypes collected along the east coast of Australia plus lines obtained by subjecting Whittet to a mutagenic agent. Initial glasshouse studies identified 19 lines that were resistant to the KY1A strain of kikuyu yellows and 4 of these, with forage quality and yield superior to Whittet, were further evaluated in the field at 2 sites using Whittet as the control. At Site 1, line 12A demonstrated a much higher level of resistance to kikuyu yellows than Whittet, with 85% of plants resisting infection compared with only 15% of Whittet plants. At Site 2, the numbers of 12A and Whittet plants infected were similar. Further tests, using kikuyu yellows inoculum collected from 11 sites along the east coast of Australia, found that only 15% of 12A plants became infected compared with 61% of Whittet plants. Thus, kikuyu line 12A was resistant to most, but not all, strains of the kikuyu yellows pathogen. Annual yield of 12A (19,008 kg DM/ha) was 24% higher than that of Whittet and 12% higher than Acacia, but the difference was significant only for Whittet. During summer, 12A produced 10,212 kg DM/ha (24% higher than Whittet), was more active in early spring, had slightly higher dry organic matter digestibility (66.7 vs. 64.0%) and was resistant to black spot infection.

Management Practices of Pasture, Range and Grazing Reserves for Livestock Production in the Tropics: A Review

The objective of the paper was to review management practices of pasture, range and grazing reserves in order to ensure steady supply of feed and promote sustainable livestock productivity in the tropics. Grazing management deals with such questions as how long should animals stay in one area and how long they should stay off it; which animals should graze what pasture; how many animals should graze together and what other activities should be integrated with grazing. Grazing management and stocking rate are the two most important variables affecting herbage production, seasonal pattern of production, herbage quality and botanical composition. Farm animals require nutrients to support body maintenance, reproduction, lactation, and growth. The nutritional needs of livestock vary according to breed, age, sex, class, stage of production, performance level and weight. Physiological and environmental stressors, such as sickness and weather, can also influence nutritional requirements. Ruminant animals, especially cattle, sheep and goats are natural grazers and possess remarkable ability to digest plant carbohydrates that is generally indigestible by most other mammals. It is natural then to assume that, grazing is the best way to supply a nutrient-dense diet to ruminant animals. Pasture land with high quality grass-legume can meet energy requirements of growing or lactating ruminants in the wet season. Energy supplementation on pasture helps in maintaining high grains and milk production. High quality forages have the ability to supply all the energy needed to maintain highly-productive ruminants throughout the growing season, but only when managed intensively. Legume-grass pastures have protein content greater than 18% during the vegetative stage. Feed resources that contain minerals include; range or pasture plants, harvested forages, concentrates and mineral supplements. The levels of minerals in plants are a function of interaction between several factors which include soil type, plant species, stage of maturity, dry matter yield, grazing management and climate. Forage conservation and preservation should be highly encouraged among farmers especially during the wet season where the feed resources are in abundant supply.

An examination of the effect of autumn closing date on over-winter herbage production and spring yield

Altering autumn management affects the herbage mass available in spring. An experiment was established to determine the effect of five autumn closing dates (CDs) on herbage production, herbage quality, leaf, stem and dead proportions and tiller density over winter. In the study 50% of the herbage available in spring was accounted for by autumn CD. Each 1 d extra a sward was closed from 25 September to 9 December increased herbage mass by 16 kg DM/ha in spring. Swards closed earlier (25 September–26 October) had consistently higher herbage masses in spring (1,301 kg DM/ha) compared to swards closed later (11 November–9 December; 703 kg DM/ha). Later closed swards had greater herbage quality compared to earlier closed swards (organic matter digestibility = 852 and 825 g/kg DM, respectively) due to increased stem and dead material in the grazing horizon of earlier closed swards. There was no effect of autumn CD on sward quality in the subsequent defoliation in spring. However, following the initial spring grazing there was an effect of autumn CD on subsequent grass growth rates; swards closed in October had a lower growth rate (33 kg DM/ha per day) compared to swards closed in November and early December (49 kg DM/ha per day). Results indicate that earlier autumn closing is beneficial to meet high-feed demand in spring but can affect sward quality and growth rates in spring.

Comparisons of nutrient solutions from organic and chemical fertilizer sources on herbage yield and quality of hydroponically produced maize fodder

We investigated the use of four nutrient solutions (organic, organo-mineral, inorganic, and a commercial hydroponics solution that served as a control) on the yield and quality of hydroponically produced maize fodder. The organic, organo-mineral, and inorganic nutrient solutions were formulated from poultry manure, Aleshinloye organo-mineral fertilizer, and NPK 20:10:10, respectively. The nutrient solutions were used to irrigate “Swan-1” maize seeds for 16 days after which herbage yield, water use efficiency, chemical composition, and in vitro variables were determined. Formulated nutrient solutions had no significant (p > 0.05) effect on recorded fodder yield values (0.96 − 1.05 kg/tray). Water use efficiency values ranged from 0.23 to 0.26 kg DM/m3 with no significant (p > 0.05) treatment effect. The organo-mineral nutrient solution decreased crude protein content but increased ash content in the plants. The other treatments had statistically similar (p > 0.05) crude protein and ash values with the control. Recorded crude protein and ash values were 8.88%−13.69% and 5.43%−8.25%, respectively. Plants irrigated with the organo-mineral nutrient solution had consistently higher (p < 0.05) mineral concentration values (3.68, 2.13, 63.60, 13.70, and 5.29 g/kg for Ca, P, K, Mg, and Na); although, P concentration was similar with the control. In vitro gas volumes and dry matter digestibility were not significantly (p > 0.05) affected by the treatments. In conclusion, the formulated organic and organo-mineral nutrient solutions produced plants with similar yield and quality as the inorganic and standard nutrient solutions.

Comparison of Spectral Reflectance-Based Smart Farming Tools and a Conventional Approach to Determine Herbage Mass and Grass Quality on Farm

The analysis of multispectral imagery (MSI) acquired by unmanned aerial vehicles (UAVs) and mobile near-infrared reflectance spectroscopy (NIRS) used on-site has become increasingly promising for timely assessments of grassland to support farm management. However, a major challenge of these methods is their calibration, given the large spatiotemporal variability of grassland. This study evaluated the performance of two smart farming tools in determining fresh herbage mass and grass quality (dry matter, crude protein, and structural carbohydrates): an analysis model for MSI (GrassQ) and a portable on-site NIRS (HarvestLabTM 3000). We compared them to conventional look-up tables used by farmers. Surveys were undertaken on 18 multi-species grasslands located on six farms in Switzerland throughout the vegetation period in 2018. The sampled plots represented two phenological growth stages, corresponding to an age of two weeks and four to six weeks, respectively. We found that neither the performance of the smart farming tools nor the performance of the conventional approach were satisfactory for use on multi-species grasslands. The MSI-model performed poorly, with relative errors of 99.7% and 33.2% of the laboratory analyses for herbage mass and crude protein, respectively. The errors of the MSI-model were indicated to be mainly caused by grassland and environmental characteristics that differ from the relatively narrow Irish calibration dataset. The On-site NIRS showed comparable performance to the conventional Look-up Tables in determining crude protein and structural carbohydrates (error ≤ 22.2%). However, we identified that the On-site NIRS determined undried herbage quality with a systematic and correctable error. After corrections, its performance was better than the conventional approach, indicating a great potential of the On-site NIRS for decision support on grazing and harvest scheduling.

The relationship between the grazing efficiency and the production, morphology and nutritional traits of perennial ryegrass varieties

AbstractRuminant grazing systems aim to optimize the proportion of grazed forage within the diet and perennial ryegrass grazing efficiency influences both the quantity and quality of herbage utilized. The objective of this study was to examine morphological and chemical plant characteristics and test for any associations with grazing efficiency. The leading perennial ryegrass varieties from the 2016 Irish Recommended List were established in a plot study and rotationally grazed by dairy cows over 3 years. Pre-grazing plant characteristics were measured and related to grazing efficiency, as measured by ‘residual grazed height’. Data were analysed using the PROC MIXED procedure to test for trait differences between varieties, and their corresponding ploidy and heading categorizations. Traits displaying significant variety variability were then tested for their correlation to grazing efficiency using the PROC GLM procedure. Tetraploid varieties exhibited superior grazing efficiency over diploids, due to their superior performance in traits correlated with grazing efficiency. Increasing organic matter digestibility and leaf proportion and decreasing neutral detergent fibre and stem height within the sward were found to increase grazing efficiency. The observed link between these plant traits and grazing efficiency indicates a possibility that they could be used to develop proxy measures to aid breeders to select for, and evaluators to measure, varietal grazing efficiency without involving animal assessments. It was concluded that this would make it logistically practical to assess large numbers of varieties in small plot trials to both breed and evaluate perennial ryegrass varieties for superior grazing efficiency.

Seasonal dynamics of cattle grazing behaviors on contrasting landforms of a fenced ranch in northern China

The number of livestock per unit area is commonly used as a proxy of grazing pressure in both experimental studies and grassland management. However, this practice ignores the impact of landform heterogeneity on the spatial distribution of grazing pressure, leading to localized patches of degraded grassland. The spatial distribution of actual grazing density thus needs to be examined. Owing to the corresponding changes in resource availability and energy consumption as livestock move across an elevation gradient, we predict that livestock will preferentially use low-land and that different temporal patterns of grazing pressure will occur in the contrasting landforms. GPS location data and a machine learning technique were used to identify the seasonal pattern and the factors driving grazing pressure on a fenced ranch. Over both low-land and sand-dune landforms, the proportion of time that livestock spent on foraging increased from 63% in July to 67% in August and 69% in September, and non-foraging behavior decreased correspondingly. In low-land, the log-transformed average foraging density significantly increased from 0.61 (i.e., total foraging behaviors in 5 days measured at 50-s intervals per 10 × 10 m grid) in July to 0.66 in August and 0.88 in September, whereas there was no significant change on sand-dunes. From July to September, the relative area of low-land foraged by cattle accounted for 31%, 35%, and 36%, respectively, and in sand-dunes the proportions increased from 45% to 47% to 51%. In low-land, the foraging density was negatively correlated with biomass (P = .07), total digestible nutrients (P < .05), and crude protein (P = .06) and positively correlated with acid detergent fiber (P < .05), whereas no such relationships were observed in sand-dunes. Our results indicate that topographic features should be considered when managing livestock, especially during periods with adverse conditions of herbage quality and quantity.

Multi-Trait Genomic Prediction Improves Predictive Ability for Dry Matter Yield and Water-Soluble Carbohydrates in Perennial Ryegrass.

In perennial ryegrass (Lolium perenne L), annual and seasonal dry matter yield (DMY) and nutritive quality of herbage are high-priority traits targeted for improvement through selective breeding. Genomic prediction (GP) has proven to be a valuable tool for improving complex traits and may be further enhanced through the use of multi-trait (MT) prediction models. In this study, we evaluated the relative performance of MT prediction models to improve predictive ability for DMY and key nutritive quality traits, using two different training populations (TP1, n = 463 and TP2, n = 517) phenotyped at multiple locations. MT models outperformed single-trait (ST) models by 24% to 59% for DMY and 67% to 105% for nutritive quality traits, such as low, high, and total WSC, when a correlated secondary trait was included in both the training and test set (MT-CV2) or in the test set alone (MT-CV3) (trait-assisted genomic selection). However, when a secondary trait was included in training set and not the test set (MT-CV1), the predictive ability was not statistically significant (p > 0.05) compared to the ST model. We evaluated the impact of training set size when using a MT-CV2 model. Using a highly correlated trait (rg = 0.88) as the secondary trait in the MT-CV2 model, there was no loss in predictive ability for DMY even when the training set was reduced to 50% of its original size. In contrast, using a weakly correlated secondary trait (rg = 0.56) in the MT-CV2 model, predictive ability began to decline when the training set size was reduced by only 11% from its original size. Using a ST model, genomic predictive ability in a population unrelated to the training set was poor (rp = −0.06). However, when using an MT-CV2 model, the predictive ability was positive and high (rp = 0.76) for the same population. Our results demonstrate the first assessment of MT models in forage species and illustrate the prospects of using MT genomic selection in forages, and other outcrossing plant species, to accelerate genetic gains for complex agronomical traits, such as DMY and nutritive quality characteristics.

Short-term mixed pastures of Lolium multiflorum, Avena sativa and Vicia sativa or Lolium multiflorum × Festuca pratensis, Avena strigosa and Vicia villosa for grazing low yielding dairy cows during winter in small-scale dairy systems in the highlands of Mexico

The study was undertaken to assess yield and herbage quality of two mixed short-term pastures of grass, oat, and vetch during the winter dry season for grazing low yielding dairy cows. The mixed pastures were termed as conventional (CON) and experimental (EXP) mixtures. CON was annual ryegrass (Lolium multiflorum cv. Westerwolds), common oat (Avena sativa cv. Chihuahua) and common vetch (Vicia sativa), and EXP was festulolium (Lolium multiflorum × Festuca pratensis cv. Spring Green), black oat (Avena strigosa cv. Saia), and winter vetch (Vicia villosa cv. Naomi). Eight low yielding Holstein cows with 462.4±43.16 kg live weight, 3.4±0.1 body condition score, milk yield of 5.1±1.7 kg/cow/day, and 135.2±88.4 days in milk were continuously grazed 4 cows/ha. A double cross-over design with 4 experimental periods was followed for animal variables. There was a significant change in net herbage accumulation on pastures between experimental periods; and no differences in animal variables. There were no significant effects in animal variables, but milk yields increased two-fold from pre-experimental yields indicating the potential of quality pastures to improve productivity in small-scale dairy systems.

Drought tolerance is determined by species identity and functional group diversity rather than by species diversity within multi-species swards

Abstract Low-input grasslands depend on the presence of grasses and legumes for the provision of nitrogen and a sufficient amount and quality of herbage for livestock. Increasing variability in the amount and distribution of rainfall, associated with climate change, is a major factor affecting production from permanent grassland and particularly grass-clover swards. Previous work has shown that introduction of deep-rooting dicotyledonous forbs into grass-legume mixtures increases functional trait diversity (FTD), which facilitates the resistance and resilience of grassland to drought. It also increases species diversity and functional group diversity (FGD). However, the role of species diversity at a given level of FGD and associated FTD for the resistance and resilience of low-input grassland towards drought remains unclear. This knowledge is required to design forage mixtures adapted to drier climatic conditions. We conducted a drought-stress experiment with 16 different sown sward types, grown in cylindrical mesocosms, combining three levels of species diversity (one, three, five) and three levels of FGD (one, two, three) all being associated with FTD in terms of phenology, rooting depth and nitrogen fixation to determine whether maximum levels of species diversity or FGD promote adaptation to drought. The study was conducted over three drought-stress cycles in an open-sided greenhouse where the climate followed ambient natural conditions. Over the duration of 685 days, we found no clear species diversity effect but a distinct species identity effect on biomass production and agronomic water use efficiency. A positive species identity effect depended largely on white clover presence and on the FGD within mixtures. The best performing mixtures for resistance and resilience combined FGD and FTD in a complementary way, irrespective of whether the swards contained three or five species, as FGD and FTD were already maximized within the best-performing three-species swards. Increasing complementarity of traits by species grown in carefully designed mixtures is one measure to achieve diversity effects and facilitate future sustainable grassland production. We propose to exploit the benefits of species identity and functional group diversity in designing future mixtures to cope with drought.

Tropical forage technologies can deliver multiple benefits in Sub-Saharan Africa. A meta-analysis

Scarcity of quantity and quality feed has been a key constraint to productivity of smallholder crop-livestock systems. Tropical forages include a variety of annual and perennial grasses, herbaceous and dual-purpose legumes, and multipurpose trees and shrubs. They have been promoted in Sub-Saharan Africa (SSA) for increasing livestock productivity and household income through higher quantity and quality of herbage, while contributing to soil improvement and higher food crop yields. For the first time, we quantitatively reviewed 72 experimental studies from across SSA to take stock of geographical distribution and forage technology focus of past research; quantify magnitudes of multidimensional impacts of forage technologies; and present variability in forage agronomy data. Improved forage technologies were classified into four groups: (i) germplasm, (ii) management, (iii) cropping system integration, and (iv) feeding regime. Mean weighted response ratios were calculated from 780 pairs of observations for 13 indicators across the five impact dimensions. Improved forage germplasm had on average 2.6 times higher herbage productivity than local controls, with strongest effect in grasses. Feeding regimes with improved leguminous forages increased milk yield by on average 39%, dry matter intake by 25%, and manure production by 24%. When forage technologies were integrated with food crops, soil loss was almost halved, soil organic carbon increased on average by 10%, and grain and stover yields by 60% and 33%, respectively. This study demonstrates the central role improved forages could play in sustainable intensification of crop-livestock systems in SSA. It highlights the need for multidisciplinary and systems-level approaches and studies to quantify synergies and tradeoffs between impact dimensions. Further research is needed to explain forage agronomic yield variability, unraveling interactions between genotype, on-farm environmental conditions, and management factors. Results from this review can inform development programs, prioritizing technologies proven successful for dissemination and indicating magnitudes of expected impacts.

The effect of stage of regrowth on the physical composition and nutritive value of the various vertical strata of kikuyu (&lt;i&gt;Cenchrus clandestinus&lt;/i&gt;) pastures

A plot study was conducted at the Gatton Research Dairy, Queensland, Australia, to quantify the effects of 5 regrowth periods (9, 11, 14, 16 and 18 days) and 4 vertical strata on the composition and nutritive value of kikuyu (Cenchrus clandestinus) pastures using a block factorial design with 4 replicates. Pasture samples were analyzed for crude protein (CP), ethanol-soluble carbohydrates (ESC), acid detergent fiber (ADF), neutral detergent fiber (aNDFom), in vitro indigestible neutral detergent fibre (iNDF240) and minerals. Metabolizable energy (ME) was then calculated from the concentrations of other nutrients. Regardless of the stage of regrowth, stems were located mainly in the bottom 1 or 2 strata, while leaves were present mainly in the top 2 or 3 strata. CP, ESC and ME declined, but aNDFom, ADF and iNDF240 increased with stage of regrowth and from top to bottom of the swards (P&lt;0.05). While herbage quality variables were affected by both factors, vertical stratum had a much larger impact on quality than stage of regrowth. These results indicate that grazing management of kikuyu pastures should be based not only on stage of regrowth but also on level of defoliation, as both have strong impacts on the nutritive value of the consumed forage.

Effect of Herbage Density, Height and Age on Nutrient and Invertebrate Generalist Predator Abundance in Permanent and Temporary Pastures

The aim of this research was to assess differences in the quantity and quality of herbage and invertebrate generalist predator abundance among permanent and temporary pastures. Two permanent pastures and four temporary ley pastures (either one year or two years since being sown) were monitored weekly for 10 weeks in the spring. Permanent pastures included a diverse range of native UK grass species, and temporary ley pastures were predominantly perennial ryegrass (Lolium perenne) with or without white clover (Trifolium repens). Weekly measurements of herbage height (in centimeters), herbage cover (fresh and dry matter in kg per hectare) and herbage density (fresh and dry matter in kg per hectare per centimeter) were obtained for each field, along with lycosid spider and carabid beetle abundance. Weekly pasture samples were used to obtain nutrient concentrations of dry matter, crude protein, neutral detergent fibre (NDF), acid detergent fibre (ADF), ash, oil, sugars, digestible organic matter in the dry matter (DOMD) and metabolisable energy (ME) in the herbage as a measure of forage quality for grazing or harvesting. A linear mixed model was used to assess the effect of sward age, herbage density and height on herbage production, nutrient concentrations and invertebrate abundance. Although this study showed that permanent pastures were associated with lower nutrient concentrations of crude protein, ash, oil and ME compared to younger and predominantly perennial ryegrass pastures, the older pastures were associated with higher carabid numbers. Furthermore, permanent pastures had a higher density of dry matter herbage compared to younger pastures, and more dense and taller swards were associated with higher lycosid numbers. The study suggests that within pastures of 3 to 20 cm height, increasing the height and density of swards increases both ME and oil concentrations in herbage, therefore enhancing forage nutrient quality. Older and more permanent pastures can be beneficial for plant and invertebrate generalist predator populations, and still provide a useful source of nutrients for forage production.

Temporal variations in leaf traits, chemical composition and in vitro true digestibility of four temperate fodder tree species

Context Many tree and shrub species are underestimated fodder resources due to insufficient knowledge about their potential feeding value, especially for goats. Aims The present work aimed at assessing productive and nutritional attributes of the foliage of the following four temperate tree species widespread in Europe: Acer pseudoplatanus, Fraxinus excelsior, Salix caprea and Sorbus aucuparia. Methods Leaf length and biomass, proximate composition, fatty acid profile, phenolic composition and in vitro true dry matter digestibility were determined along the vegetative season. Key results The leaf length of the four species was significantly related to leaf biomass and can be considered as a proficient proxy for estimating leaf biomass. The differences found among the species were remarkable, although weakly related to temporal changes, especially when considering fatty acid and phenolic compositions. Fraxinus excelsior sprouts were the most productive, with a mean biomass of 13.2 g dry matter (DM) per sprout at the end of the growing season. Its foliage showed also the lowest phenolic concentrations (average total extractable phenols of 11.25 g/kg DM), resulting in the highest digestibility values (average in vitro true dry matter digestibility of 56.5 g/kg DM). Digestibility of S. aucuparia was similar, but its lower polyunsaturated fatty acid concentration (average value of 62.13 g/kg DM) could reduce the interest for this species as a feeding resource for goat dairy products with healthy properties. The lower digestibility found for A. pseudoplatanus and S. caprea (average values of 43.3 and 46.2 g/kg DM, respectively) may be related to their higher phenolic concentrations (average total extractable phenols of 45.9 and 47.3 g/kg DM, respectively). Conclusions The four species could represent an appealing feedstuff for goat nutrition, due to the valuable and complementary nutritional characteristics of their foliage. Implications The use of the studied species as fodder resource may be particularly relevant during drought periods and in the late summer when herbage quality decreases, especially in terms of crude protein and fatty acid profile.

Mitigating the anti-nutritional effect of polyphenols on in vitro digestibility and fermentation characteristics of browse species in north western Ethiopia.

Browse species are important sources of forage for livestock in Ethiopia, especially during the dry season, when the quality and quantity of green herbage is limited. However, browse species have anti-nutritional factors, such as polyphenols. This study evaluated the extent to which polyethylene glycol (PEG) can reduce the anti-nutritional effects of polyphenols whose extent is expected to vary depending on the species type and season on the in vitro fermentation of these plant samples. We selected ten browse species commonly used as livestock feed based on their tannin content, and sixty samples of the leaf and twig of these species were collected during the wet and dry seasons. The study was designed as 10 × 2 × 2 factorial arrangement with 10 browse species (Acacia nilotica, Crateva adonsonia, Dombeya torrida, Ekebergia capensis, Ensete ventricosum, Erythrina brucei, Maesa lanceolate, Sesbania sesban, Stereospermum kunthianum, and Terminalia laxiflora), 2 seasons (wet and dry) and 2 states of PEG (with and without PEG). The effects of tannin on the nutritive characteristics were also evaluated by adding PEG as a tannin-binding agent. The chemical composition and in vitro fermentation products of these samples differed significantly (p < 0.001) among browse species. Specifically, total extractable phenol (TEP) ranged from 26.3 to 250.3 g/kg, total extractable tannin (TET) from 22.8 to 210.9 g/kg, and condensed tannin (CT) from 11.1 to 141.3 g/kg, respectively. Season, species, and their interaction have a significant (p < 0.05) effect on the chemical composition and fermentation characteristics of most browse species. The addition of PEG increased gas production (GP), in vitro organic matter digestibility (IVOMD), metabolizable energy (ME) concentration, dry matter degradability (DMD), and volatile fatty acids (VFA), on average, by 76.8%, 47.9%, 42.2%, 21.2%, and 20.2%, respectively. Secondary polyphenols (TEP, TET, CT, and SCT) were significantly (p < 0.001) and negatively correlated with GP, IVOMD, ME, and VFA. Preferable species namely E. ventricosum, S. sesban, M. lanceolata, E. capensis, and A. nilotica were selected for supplementation in terms of their chemical composition, IVOMD, and mitigating effects of PEG on anti-nutritional functions of their secondary compounds. In conclusion, PEG markedly reduced the anti-nutritional effects of polyphenols and improved the in vitro fermentation of browse species harvested in contrasting seasons.

Forage Yield and Quality Attributes of Berseem Clover Genotypes under Mediterranean Climate

It is quite significant to develop annual and high-yield forage legumes to be pure-sown or intercropped with graminae species in winter cropping systems of Mediterranean region. In this sense, berseem clover is considered as a significant species for Mediterranean region. Therefore, this study was conducted to determine yield and herbage quality attributes of berseem clover (Trifolium alexandrinum L.) genotypes in Çukurova region with dominant Mediterranean climate. Experiments were conducted over the experimental fields of Eastern Mediterranean Agricultural Research Institute (Doğankent/Adana) in winter intermediate cropping system (November-April) of 2010-11 and 2011-12 growing seasons. Experiments were carried out in randomized blocks design with 3 replications. In the first and second year of the experiments, green herbage (GH) yields varied respectively between 53.3-79.7 and between 22.7-32.3 t/ha; dry matter (DM) yields varied respectively between 7.26-12.02 and 5.16-7.42 t/ha; crude protein (CP) ratios varied respectively between 11.37-15.39 and between 15.22-18.88%; digestible dry matter (DDM) ratios varied respectively between 61.10-68.08 and between 56.84-67.70%, acid detergent fiber (ADF) ratios varied respectively between 27.22-41.45 and between 23.07-31.41%; relative feed values (RFV) varied respectively between 99.3-155.0 and between 146.5-190.5. In both years, genotypes 3, 8, 15, 16, 17 and18 had greater DM yields than the standard cultivar and the other genotypes. These genotypes were also prominent w-for herbage quality attributes. Genotype 18 was registered under the name of “DERYA” in 2015 and the other promising genotypes are still being used in on-going breeding studies.

The effect of spring grass availability and grazing rotation length on the production and quality of herbage and milk in early spring

AbstractThe importance of spring grass in the diet of early lactation dairy cows has been widely acknowledged. Numerous studies completed on a plot/paddock basis have identified methods of increasing herbage availability in spring, but little focus was placed on how this impacts animal production. The aim of the current study was to investigate the impact of opening farm cover (OFC; grass availability on farm at turnout in spring; 1036 (high), 748 (medium) and 544 (low) kg DM/ha) and spring rotation length (fast – 56 days and normal – 63 days) on animal performance in early lactation and herbage production and quality. Spring rotation length had little effect on animal performance, herbage variables or sward composition. High OFC increased pre-grazing herbage mass, allowing for increased daily herbage allowance (DHA) compared to medium and low OFC. There was a reduced proportion of leaf in the sward of the high OFC compared to the low OFC, resulting in lower organic matter digestibility. Despite the reduction in sward quality observed as a consequence of achieving high OFC in spring, the greater DHA available to animals increased milk production (+1.4 kg milk/cow/day). Additionally, animals grazing a medium or low OFC had a greater requirement for silage supplementation in spring (+1.3 kg DM/cow/day). The benefits of the higher DHA highlighted in the current study suggest that autumn grazing management must be adapted to increase herbage availability in spring. However, the benefits observed in milk production did not persist beyond the first grazing rotation.