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To assess the potential for enhancing lodging resistance in legumes through the application of plant growth regulators (PGR) and changes in stem structure, the stem morphological and anatomical characteristics, as well as the chemical composition, of Vicia sativa and Vicia pannonica were analysed before and after treatment with different doses of PGR trinexapac-ethyl. The aim was to identify stem morpho-anatomical components that impact lodging resistance, quantify the dose-dependent effect of the chosen PGR on the Vicia stem and examine if stem lodging resistance could be improved through PGR application, as well as determine if some of the stem characteristics could be used as markers for lodging resistance prediction.
Although in both species lodging index increased (14–126%), suggesting improved resistance to lodging, and stem height decreased (12–38%) upon PGR application, the impact on V. sativa was more pronounced. The findings indicate that, apart from stem height, none of the examined morpho-anatomical characteristics showed a high and significant correlation with the lodging index. Therefore, none of these characteristics can be used as a marker for predicting lodging resistance. Increased proportion of cortex, cylinder parenchyma and collenchyma, along with reduced central cavity, might contribute to a greater lodging resistance in V. sativa. PGR decreased the amount of lignin, cellulose and hemicellulose. These results encourage the use of PGR for lodging resistance improvement in vetches, through the reduction of stem height, since this modification did not adversely affect the stem structure or grain yield.
The study evaluated forage and livestock performance in different grazing systems over two years. Treatments were three contrasting grazing systems: (I) N-fertilized bahiagrass (Paspalum notatum Flüggé) in the summer overseeded during the winter by N-fertilized ryegrass (Lolium multiflorum) and oat (Avena sativa L.) (Grass + N); (II) unfertilized bahiagrass during the summer overseeded with ryegrass + oat and a blend of clovers (Trifolium spp.) in the winter (Grass + Clover); (III) unfertilized bahiagrass and rhizoma peanut (RP; Arachis glabrata Benth.) mixture during summer, overseeded during winter by ryegrass + oat + clovers mixture (Grass + Clover + RP). Average daily gain (ADG), gain per area (GPA), and stocking rate (SR) in the winter did not differ across treatments and averaged 0.87 kg/d (P = 0.940), 303 kg/ha, and 2.72 AU/ha. In the summer, Grass + Clover + RP had greater ADG than Grass + N (0.34 vs. 0.17 kg/d, respectively). During the summer, the GPA of Grass + Clover + RP was superior to Grass + N (257 vs. 129 kg/ha, respectively), with no difference in SR among treatments at 3.19 AU/ha. Over the entire year, ADG and GPA tended to be greater for Grass + Clover + RP. Annual SR differed between treatments, where Grass + N was greater (3.37 AU/ha) than the other treatments, which averaged 2.76 AU/ha. Integration of legumes into pasture systems in the summer and winter contributes to developing a sustainable grazing system, reducing N fertilizer use by 85% while tending to increase livestock productivity even though SR was decreased by 18%.
Productive and nutritional traits of forage species in various regions worldwide depend on different management strategies. This study aimed to evaluate the effects of harvest frequency (56, 77 and 98 days) and season of the year (rainy and dry) on the nutritional value and fractionation of carbohydrates and proteins of Stylosanthes genotypes (S. seabrana, S. scabra, S. mucronata and Stylosanthes spp. cv. Campo Grande). The experiment was conducted using a randomized complete block design with a split-plot arrangement and four repetitions. Contents of neutral detergent fibre (NDF), acid detergent fibre (ADF), in vitro digestible dry matter (IVDDM), condensed tannins and total phenolic compounds were influenced by the interaction of harvest frequency and season of the year. The 98-day harvest frequency resulted in lower IVDDM (579 g/kg) due to the high NDF and ADF concentrations during the rainy season. S. seabrana and S. scabra showed a higher proportion of A + B1 and B2 carbohydrate fractions, while the C fraction in the rainy season was greater in the Campo Grande, resembling S. seabrana. S. scabra displayed 15% of the crude protein in fraction A. The bromatological traits of Stylosanthes spp. did not decline sharply owing to plant age advancement, indicating these genotypes are suitable for forage production systems in tropical or semiarid regions.
Lemongrass essential oil (LEO) has been evaluated as a silage additive to improve silage fermentation and reduce fermentative losses. The present study aimed to evaluate the effects of increasing levels of LEO on whole-plant sorghum silage (WPSS) fermentation profile, fermentation losses, chemical composition, dry matter (DM) and neutral detergent fibre (NDF) in vitro degradation and aerobic stability. Five cultivars and fifty experimental silos were used to evaluate the following LEO levels: 0, 1, 2, 3 and 4 ml kg−1 DM of WPSS. The material was compacted (650 kg m−2) and the silos were sealed, weighed and stored at room temperature for 167 days. The addition of LEO linearly decreased butyric acid content and the ratio between lactic and acetic acids. Intermediate levels of LEO increased NH3-N and reduced lactic and acetic acids content. LEO linearly decreased silage gas losses. However, LEO did not affect total silage losses and DM recovery. Intermediate levels of LEO addition decreased organic matter and crude protein in the WPSS. The addition of LEO did not affect other chemical composition parameters, DM and NDF in vitro degradation, and pH and temperature of the silage after aerobic exposure. Thus, LEO supply in WPSS reduces gas losses, butyric acid concentration, and the ratio between lactic and acetic acids. However, LEO does not improve the chemical composition, in vitro degradation, and aerobic stability of WPSS.
Invasive annual grasses such as medusahead [Taeniatherum caput-medusae (L.) Nevski] and barb goatgrass (Aegilops triuncialis L.) are negatively impacting grasslands of the western United States. Over the last decade, research has shown that aminopyralid and other growth-regulator herbicides applied just before flowering greatly reduce viable seed production in several invasive annual grasses. Moreover, it has been shown with T. caput-medusae that using aminopyralid to reduce seed production in one year consistently reduces and sometimes nearly eliminates cover the following year. Our goal in this study was to extend this research to A. triuncialis, a weed for which limited herbicide and other management options exist. Based on previous research, we hypothesized aminopyralid applied several days before flowering at just 22% of the maximum registered rate (0.069 kg ae ha−1) would almost completely prevent production of viable A. triuncialis seeds in the greenhouse. In four experiments, aminopyralid reduced seed viability from between 65% and 95% to between 1% and 5%. Therefore, aminopyralid will likely control A. triuncialis in the field. Because aminopyralid is phytotoxic to many broadleaf species, it may be possible to use aminopyralid to simultaneously control mixed stands of invasive forbs, A. triuncialis, and T. caput-medusae. However, there are risks to applying aminopyralid where native and desirable nonnative forbs occur. Past research on T. caput-medusae suggests controlling A. triuncialis with aminopyralid will increase production of desirable annual forage grasses.
Ventenata [Ventenata dubia (Leers) Coss.] is one of several annual grass invaders of the western United States. Ventenata dubia is documented reducing the forage availability for livestock and wildlife as well as lowering biodiversity in the Great Basin. This species has recently spread to the Great Plains, where it could bring these impacts with it. We attempt to answer questions on whether or not conservation practices, in this case removal of V. dubia with herbicide, result in recovery of forage resources and biodiversity. We answer these questions by measuring biomass, cover, and nutrient content 1-yr posttreatment at 9 sites in Sheridan County, WY, conducted in two years. Perennial grasses have higher crude protein and total digestible nutrients than V. dubia, and removal of V. dubia resulted in a positive perennial grass response both years. Further, the differences in pattern of growth between perennial and annual species, with annual grasses quickly senescing early in the year, make perennial grasses a more dependable forage base with higher available nutrients. Interestingly, total biomass and nutrient mass did not change after V. dubia removal due to equal replacement with perennial grasses. Species richness and diversity were unaffected by removal of V. dubia. Our results suggest that managing invasive annual grasses, particularly V. dubia, in the Northern Great Plains can improve forage resources for livestock and wildlife while maintaining species diversity. Therefore, proactive monitoring and management efforts to prevent spread should be prioritized in this region.
Guinea grass (Megathyrsus maximus Jacq.) is an important forage species in vast rangelands/grasslands of India and several tropical countries owing to its high biomass yield, good nutritional quality and wide adaptation. Evaluation of the existing natural variation and selection of desirable genotypes is the most plausible breeding method for this apomictic and polyploid grass. Developing a core sub-set to narrow down the number of germplasm required for future genetic studies is also pertinent. The present study involved characterization of 152 diverse M. maximus germplasm representing collections from different agro-ecological zones of India as well as those procured from Africa and Brazil; and development of a core sub-set. Nineteen metric, seven non-metric and nine nutritive traits together established the presence of wide variability among the genotypes. Clustering of the genotypes resulted in eight distinct clusters. The largest cluster included genotypes from Ethiopia, north India, north-western India, south India and north-eastern hill region, thus represented the highest diversity. Eleven of the total 26 Ethiopian genotypes clustered together. Non-metric morphological traits effectively differentiated the genotypes, and were associated with nutritional quality also. Genotypes which flowered once in a year showed slightly better crude protein and digestibility. The clusters were further sub-clustered and representatives were selected to develop the core sub-set of 23 genotypes comprising 20 indigenous and three exotic accessions. Comparison of the range of diversity and mean value for traits as obtained in the core sub-set and that in the total germplasm indicated successful capturing of maximum diversity in the core sub-set.
Pearl millet (Pennisetum glaucum (L.) R.) is an important crop for rainfed production systems and can play a significant role as a feed source for ruminants owing to its high yield and drought tolerance. It is well-established that the maturity stage can influence the chemical composition as well as the nutritional value of crops traditionally used for silage production, although quantitative evidence that this occurs with pearl millet under rainfed conditions is lacking. The current research assessed the agronomic characteristics, ensilability, intake and digestibility of a Brazilian pearl millet cultivar (IPA BULK1-BF) harvested at four different growth stages. Forage was harvested at 35, 50, 65 and 80 days after sowing and ensiled under laboratory and farm conditions. Apparent digestibility of the silages was determined using 24 male lambs. The results showed that dry matter (DM) and panicle and stem proportions increased with the advancement maturity. The silage evaluations showed that DM, total and non-fibrous carbohydrates and lignin concentrations increased, while crude protein, ADF and in vitro DM digestibility decreased with the increase in plant maturity. Additionally, the fermentation characteristics were improved with the increasing maturity. The digestion study showed that intake of DM and N as well as digestibility of DM and fibre fractions decreased, while lignin intake increased. The results obtained for the production of dry and digestible DM, the ratio of plant fractions and fermentation parameters indicate the possibility of harvesting pearl millet forage after 50 days after sowing for silage production in the Brazilian semi-arid region.
Although lignin has been negatively correlated with neutral-detergent fibre (NDF) digestibility (NDFD) in ruminants and used to predict potential extent of NDF digestion of forages, selection of an analysis, Klason lignin (KL) or acid-detergent lignin (ADL), to describe that the nutritionally relevant lignin has not been resolved. Dismissed as an artifact is the difference between KL and ADL (ΔL). A question is whether ΔL influences NDFD. We evaluated the relationships of ΔL, KL and ADL with NDFD in order to determine the nutritionally homogeneous or heterogeneous nature of KL. Data sets from two laboratories (DS1 and DS2) were used that included ADL, KL and in vitro NDFD at 48 h (NDFD48). DS1 contained seven C3 grasses, seventeen C4 maize forages and nineteen alfalfas, and DS2 had fifteen C3 grasses, eight C4 forages and six alfalfas. Mean ΔL was greater than ADL in C3 and C4 samples and less in alfalfas. Within forage type and laboratory, ΔL was not correlated with NDFD48 (r −0·34–0·49; all P > 0·17). ADL was more consistently correlated with NDFD48 (r −0·47–−0·95; P < 0·01–0·21) than with KL (r 0·03–−0·91; P < 0·01–0·94). ΔL as a proportion of KL was correlated with NDFD48 in C3 and C4 samples (r 0·44–0·76; P < 0·01–0·08). The differing behaviours of ΔL and ADL relative to NDFD48 indicate that KL is a nutritionally heterogeneous fraction, the behaviour of which may vary by forage type and ratios of ADL and ΔL present.
The comparison of the effects of all forage offering methods would be particularly useful information in modeling growth performance and rumen fermentation of dairy calves. Therefore, this study attempted to evaluate the effects of methods of oat hay provision on growth performance, rumen fermentation and biochemical blood indices of dairy calves during preweaning and postweaning periods. At birth, 40 female Polish Holstein-Friesian calves (3 days of age; 39.6 ± 0.39 kg BW) were randomly assigned to four treatment groups differing in the access to chopped oat hay: CON (control, starter without oat hay), OH (starter feed containing 10% DM basis oat hay), OH-FC (starter feed containing 10% DM basis oat hay and oat hay fed as free-choice provision in different buckets) and FC (starter feed and oat hay fed as free-choice provision in different buckets). The calves were weaned on day 56, and then the study continued until day 84. Intakes of starter feed and oat hay were recorded daily, whereas BW and hip height (HH) on day 3 and then every 14 days. Samples of blood were collected on the initiation of experiment and then every 14 days, and rumen contents on day 28, 56 and 84. No treatment effects were found for starter, starch, CP, total DM intake, average daily gain, feeding efficiency, change in HH, ruminal fluid pH, concentrations of ruminal propionate and NH3-N, concentrations of urea nitrogen and non-esterified fatty acids in the blood. There were differences between treatments in terms of ruminal total volatile fatty acids and molar concentrations of acetate, butyrate and acetate to propionate ratio; highest in OH and OH-FC groups, especially during the postweaning period. On the other hand, lower concentrations of iso-valerate were found in OH and OH-FC groups on day 56 and 84. The concentrations of IGF-I throughout the experiment and β-hydroxybutyrate during the postweaning period in the blood were influenced by treatment, with the greatest values observed in OH and OH-FC calves. Results of this study indicate that starter feed containing chopped oat hay improves rumen fermentation parameters, which might allow successful transition from preruminant to mature ruminant state. Also, providing chopped oat hay with pelleted starter feed seems to be a better method than free-choice supplementation.
Many studies have shown that metabolic efficiency of ruminants can be significantly decreased when B-vitamin supply is insufficient. Under the present state of knowledge, the amounts of B vitamins available for intestinal absorption cannot be predicted based on diet composition. Therefore, in an attempt to increase our understanding of the effects of dietary factors, on B-vitamin supply for dairy cows, the effects of increasing amounts of extruded linseed in diets based on hay (permanent grassland hay, H; Experiment 1) or corn silage (CS; Experiment 2) on apparent ruminal synthesis (ARS) of thiamin, riboflavin, niacin, vitamin B6, folates and vitamin B12 were evaluated. In each experiment, four lactating Holstein cows fitted with cannulas in the rumen and the proximal duodenum were used in a 4 × 4 Latin square design. In both experiments, the dietary treatments consisted of an increasing supply of extruded linseed representing 0%, 5%, 10% or 15% of diet DM. The forage : concentrate ratios were 50 : 50 and 60 : 40 for Experiments 1 and 2, respectively. Duodenal flow was determined using YbCl3 as a marker. The ARS of each B vitamin was calculated as duodenal flow – daily intake. In both experiments, treatments did not affect thiamin, riboflavin, niacin and vitamin B12 duodenal flow or ARS. Increasing the dietary concentration of extruded linseed decreased folate intake in Experiment 1 and vitamin B6 intake in Experiment 2 but resulted in a greater duodenal flow of vitamin B6 and folates regardless of the forage used in basal diet. Greater dietary linseed concentrations decreased vitamin B6 apparent degradation in the rumen in CS-based diet only and increased folate ARS in both H- and CS-based diets. Increasing linseed concentration of isonitrogenous and isoenergetic diets increased vitamin B6 and folate supply to dairy cows, both with H- and CS-based diets.
The objective of this meta-analysis study was to develop and validate equations estimated from in situ and in vitro methods to predict in vivo ruminal digestibility of organic matter (OM) of beef cattle diets. The database was composed of individual data of 23 diets from six experiments. Information collected from these studies was: in vivo digestibility and degradation parameters of OM calculated from in situ and in vitro incubations. The values of estimated times for the in situ and in vitro incubations to access in vivo digestibility of OM, and differences between degradation at 24, 48 and 72 h (in situ and in vitro) and in vivo digestibility were analysed in a model that included the fixed effects of forage neutral detergent fibre level. Thereafter, a multiple stepwise regression was carried out using OM digestibility as a dependent variable and degradation parameters (A = water-soluble fraction; B = potentially degradable water-insoluble fraction; and kd = degradation rate of fraction B) as independent variables. Equation validation was performed using data from a seventh experiment that have the same methods than previous studies. Stepwise regression results showed that the kd contributed significantly in most of the algorithms derived to predict in vivo digestibility. Validation analysis showed that equations developed from both in vitro and in situ incubations accurately estimated the in vivo digestibility of OM (P > 0.05). Our results suggest that equations developed to estimate OM digestibility showed both precision and accuracy; however, in situ method presented better results than in vitro.
The pastoral systems of Eastern Africa have been affected by the alternated incidence of recurrent drought and flood for the last decades, aggravating poverty and local conflicts. We have introduced an innovation to convert floods to productive use using water spreading weirs (WSW) as an entry point to capture and spread the torrential flood emerging in the neighboring highlands into rangelands and crop fields of low-lying pastoral systems in Afar, Ethiopia. The productivity and landscape feature have changed from an abandoned field to a productive landscape within 3 years of intervention. The flood patterns and sediment loads created at least four different crop management zones and productivity levels. Based on moisture and nutrient regimes, we developed land suitability maps for integrating crops and forages fitting to specific niches. The outcome was a fast recovery of landscapes, with 150% biomass yield increment, increased access to dry season feed and food. These positive outcomes could be attributed to the proper design of weirs, joint planning and execution between pastoralists, researchers and development agents, identification and availing best-fitting varieties for each management zone and developing simple GIS-based parcel level maps to guide development agents and pastoralists. The major ‘agents’ were community leaders (‘Kedoh Abbobati’) who keenly debated potential benefits and drawbacks of innovations, enforced customary rules and byelaw and suggested changes in approaches and choices of interventions. In general, an innovation system approach helped to create local confidence, attract attention of government institutions and helped local actors to identify investment areas, develop implementation strategies to increase productivity, define changes as it occurs and minimize conflicts between competing communities. However, the risk of de facto use of a plot of communal land translating into long-term occupation and ownership may be impacting a communal territory and social cohesion that was subject to other collective choice customary rules.
The accuracy and precision of the National Research Council (NRC), Gesellschaft für Ernährungsphysiologie (GfE) and Institut National de la Recherche Agronomique (INRA) systems for predicting the digestible energy (DE) value of hays were determined from the results of 15 digestibility trials with natural grassland hays and 9 digestibility trials with lucerne hays that all met strict experimental and a tight corpus of methods. The hays were harvested in the temperate zone. They covered broad ranges of chemical composition and DE value. The INRA system was more accurate than the other two systems, with the bias between the predicted and measured DE values of natural grassland and lucerne hays averaging −0.11 and −0.04 MJ/kg DM with the INRA system, 0.34 and −0.70 MJ/kg DM with the NRC system and −0.50 and −1.69 MJ/kg DM with the GfE system (P < 0.05). However, the precision of the three systems was similar; the standard error of prediction corrected by bias was not significantly different (P > 0.05). The GfE system underestimated the DE value of hays, especially of lucerne hays. The differences between the predicted and measured DE values resulted mainly from the errors in the prediction of organic matter digestibility and energy digestibility for both natural grassland and lucerne hays. Discrimination according to botanical family (grassland v. lucerne) can help improve the prediction of the DE value of hays. The choice of appropriate predictive variables is discussed in the light of differences in chemical composition and digestibility of the various cell wall components of grassland and lucerne hays. Neutral detergent fiber (NDF) may thus be preferable to ADF in the prediction equation of the DE value of lucerne hays, whereas ADF and NDF may both be relevant for natural grassland hays.
Green biorefineries provide novel opportunities to use the green biomass efficiently and utilize the ecosystem services provided by grasslands more widely. The effects of the inclusion of fractionated grass silage solid fraction (pulp) on feed intake, rumen fermentation, diet digestion and milk production in dairy cows were investigated. Pulp was separated from grass silage using a screw press simulating a green biorefinery. Partial removal of liquid from forage increased DM concentration from 220 to 432 g/kg and NDF from 589 to 709 g/kg DM while CP decreased from 144 to 107 g/kg DM. A feeding trial using an incomplete changeover design with 24 Nordic Red cows and two 3-week periods was conducted. The pulp replaced grass silage in the diet at 0 (P0), 25 (P25) and 50 (P50) percentage of total forage, which was fed ad libitum with 13 kg of concentrate for all treatments. The forage DM intake was highest on P25 (14.1 kg/day) while P0 and P50 did not differ from each other (13.2 and 13.0 kg/day, respectively). There were no differences between the treatments in rumen pH or ammonia N, but the proportion of acetate increased with increasing pulp inclusion. The digestibility was measured using acid insoluble ash and indigestible NDF (iNDF) as internal markers. Neither of the markers detected differences in NDF digestibility, but according to iNDF, apparent total tract organic matter digestibility decreased with increasing pulp inclusion. The cows maintained milk production at P25, but it showed some decline at P50 (energy-corrected milk at P0 and P25 was 39.8 kg/day while for P50, it was 38.5 kg/day, P = 0.056) and the milk protein yield significantly declined with higher pulp inclusion. Simultaneously, the nitrogen use efficiency in milk production increased. It seems that the fibrous grass-based fraction from a biorefinery process has potential to be used as a feed for ruminants.
Kernza® intermediate wheatgrass (Thinopyrum intermedium) is a novel perennial grain and forage crop with the potential to provide multiple ecosystem services, which recently became commercially available to farmers in the USA. The viability and further expansion of this promising crop require understanding how it may fit the needs of farmers’ livelihoods and the structure of their farming systems. However, no prior research has studied the perceptions and experiences of Kernza growers. The goals of this research were to understand why farmers grow Kernza, how Kernza fits into their systems and identify challenges for future research. We conducted in-depth interviews with ten growers in the North Central USA during the summer of 2017, who accounted for a third of the Kernza farmers in the USA at the time. All farmers had a positive attitude toward experimentation and trying new practices, and they were interested in Kernza for its simultaneous ecological and economic benefits. Kernza was marginal in terms of area, quality of fields and resources allocated in the farm systems, which also meant that farmers maintained low costs and risks. Growers utilized and valued Kernza as a dual-use crop (grain and forage), sometimes not harvesting grain but almost always grazing or harvesting hay and straw for bedding. Weeds were perceived as a challenge in some cases, but Kernza was valued as a highly weed-suppressive crop in others. Farmers requested information on optimal establishment practices, assessment of forage nutritive value, how to maintain grain yields over years, weed management, markets and economic assessment of Kernza systems. These results agree with other cases on sustainable practices adoption showing that engaging farmers in the research process from the beginning, identifying knowledge gaps and testing management alternatives are critical for the success and expansion of novel agricultural technologies.
We determined how pasture and grazing management practices affected the number of days hay was fed to cattle by season. Data were collected from a survey of Tennessee cattle producers. Days of cattle on hay varied across seasons because of variations in forage production and weather. The number of days hay was fed to cattle varied with pasture-animal management practices such as rotating pastures, forage mixtures, and weed management strategies. Having mixtures of cool- and warm-season grasses reduced the number of days on hay in the winter, spring, and summer months indicating benefits from diversified forages.
Adding corn silage (CS) instead of alfalfa hay (AH) to the finely ground starter diet would improve calf performance if feed intake or feed efficiency is increased. We investigated the effects of replacing AH with CS in the starter diet on nutrient intake, digestibility, growth performance, rumen fermentation and selected blood metabolites in Holstein calves. Newborn male calves (n = 30; 3 days of age; 40.2 ± 1.28 kg BW) were assigned randomly to three groups receiving starter diets containing chopped AH (10% dry matter (DM) basis; AH diet), CS (10% DM, CS diet) or their combination (each at 5% level; AHCS diet). The starter diets had the same nutrient composition but differed in DM content (91.2%, 87.5% and 83.8% for AH, AHCS and CS, respectively). The calves were weaned on day 50, and the study continued until day 70. Nutrient intake, BW (at weaning and at the end of the study) and body measurements were not affected by the diet. During the post-weaning period, average daily gain tended to be greater on CS than on AH diet. Feed efficiency was greater in CS than in AH or AHCS calves during the post-weaning period. Digestibility of neutral detergent fiber was greater in AHCS and CS compared with AH during the post-weaning period. Concentration and profile of volatile fatty acids and ruminal fluid pH were not affected by the diet. Replacing AH with CS in the starter diet had no effect on feed intake, growth performance and general health of the calves. These results indicate that AH and CS can be used interchangeably in dairy calf starter diets until 70 days of age, allowing dairy producers more choices in selecting the feed ingredients.
Feeding big round-bales in round-bale feeders are known to reduce labor and costs. However, one disadvantage is the high feed wastage. The aim of these experiments was therefore to investigate the effect of feeder design, type of roughage and size of round-bales on feed wastage in sheep. Four round-bale feeders (Diagonal Rail Sheep Circular Feeder (RD), Knarrhult Flexible Round-Bale Feeder (KR), Telemark Round-Bale Feeder (TR) and Standard Sheep Circular Ring Feeder (RV)) were distributed into four identical experimental pens and used in both experiments. In Experiment 1, two types of roughages were used; Roughage 1: low-quality, grass silage harvested at late stage of maturity with dry matter (DM) content of 560 g/kg and Roughage 2: high-quality, hay harvested at an early stage of maturity with DM content of 738 g/kg. In Experiment 2, ewes were offered hay harvested at the late stage of maturity with DM content of 766 g/kg as half and whole round-bales. In both experiments, four groups of 10 ewes of the Norwegian White breed were rotated between the experimental pens and each treatment lasted for 4 days. Feed wastage (roughage on the ground surrounding the feeder) was collected daily. The amount of feed wastage was generally high. The type of roughage (Experiment 1) had a large effect on feed wastage (P < 0.001), where Roughage 1 had a mean feed wastage of 1.88 kg DM/day per ewe and Roughage 2 had 0.48 kg DM/day per ewe. When Roughage 1 was provided, it was evident that the ewes pulled out the long fibrous stems of the feeders and left them as wastage while selecting the leaves. This was not the case for Roughage 2. When feeding half round-bales (Experiment 2), the mean feed wastage was 1.50 kg DM/day per ewe compared to 2.88 kg DM/day per ewe when feeding whole round-bales (P < 0.001). This is probably due to the ewes spending more time eating with their heads inside the feeder when fed half round-bales (P < 0.001) and thus dropped more of the potential wastage inside the feeder. Less feed inside the feeder may also be the reason that feed wastage decreased gradually from Day 1 to Day 4 in both experiments (P < 0.001). Feeder design also had a significant impact on feed wastage (P < 0.001). We conclude that providing early harvested roughage and feeding half round-bales significantly reduced feed wastage.