Legume Hay Research Articles

Range Potential of Pennsylvania Upland Plant Communities: Mineral Concentrations of Selected Plant Species

ABSTRACT The purpose of this trial was to determine the mineral concentration of various weeds that could potentially be part of the grazing animal's diet. Mineral content of plant species from three ungrazed and unimproved upland range communities (old field, young pine, and established hardwood) were evaluated at three locations in Pennsylvania. Vegetation samples were obtained in the spring, summer, and fall from each of the nine community-location combinations. A total of 31 species were analyzed for Mg, P, Ca, K, and Cu concentrations. Mineral values were compared to published dietary recommendations for beef and sheep and to mean compositions of corn silage, grass hay, and legume hay also sampled in Pennsylvania. Practically all sampled weeds met or exceeded beef and sheep dietary recommendations for Mg and Ca concentrations, with a lesser proportion of weed species meeting or exceeding P dietary recommendations. Several weed species sampled had an undesirably high Ca:P ratio, but the K:(Ca + Mg) ratio indicated that weeds were not generally tetanigenic. These results suggested that plant species growing in unmanaged communities can contribute macrominerals (particularly Mg and Ca) and microminerals (Cu) in sufficient amounts to negate or reduce the incidence of hypomagnesemia and other metabolic diseases. The community and geographic location in which sampled plants grew were generally not important in detennining mineral concentrations. Season tended to be more important than location, but also had minor effects on Mg, P, Ca, K, and Cu concentrations.

The effect of forage legume supplementation on digestibility and body weight gain by sheep fed a basal diet of maize stover

Growth and digestibility experiments were conducted with Ethiopian highland sheep offered a maize stover basal diet and supplemented with one of the three legume hays ( Desmodium intortum, Macrotyloma axillare and Stylosanthes guianensis), legume hay plus cottonseed cake, and cottonseed cake alone, to investigate feed intake, digestibility and body weight change. Sheep in the M. axillare supplemented group recorded higher dry matter and nitrogen intake, and showed a higher gain in body weight. When legumes were given in combination with cottonseed cake, P. intortum and M. axillare supplemented sheep recorded similar body weight gains. S. guianensis supplemented sheep lost weight during the first phase and showed relatively low bodyweight gains during the second phase. Legumes fed together with cottonseed cake as a supplement to maize stover increased digestibility of most dietary soluble and cell-wall constituents compared with legume supplements alone.

Characterization of the Management Practices of the Top Milk Producing Herds in the Country

Out of 128 surveys mailed to dairy farms that had been identified by the nine DHI processing centers as the top milk producing herds in the country, 61 surveys were returned. The predominant forage being fed was corn silage, followed by legume hay and haylage. On average, 6.7 feed additives and 3.5 alternative feeds were fed. Producers reported the following incidences of metabolic disorders: parturient paresis, 7.2%; displaced abomasum, 3.3%; ketosis, 3.7%; and nonspecific downer cow syndrome, 1.1%. Producers scheduled detection of estrus 3.1 times per day. Only 18.3% of the herds used routine synchronization of estrus. Artificial insemination was used on 94.8% of the cows and 88.5% of the heifers. The most important trait in sire selection was PTA for milk. For mastitis control, 75.4% of the producers practiced predipping, 85.2% used individual paper towels, 93.4% practiced postdipping, and 95.1% treated all cows at cessation of milking. Increased profitability and lower costs or higher returns were the primary motivators of these producers. Veterinarians were the most frequent source of information, followed by farm magazines. Satellite delivery of educational programs was the least acceptable delivery method. Extension professionals need to be cognizant of the producers’ preferred information sources and delivery systems to ensure accurate, timely, cost-effective transfer of technologicaladvances.

Growth of and digestibility by sheep fed diets comprising mixtures of grass and legume hay compared with those fed high-grain diets

A digestibility trial with 24 mature wethers and a growth trial with 54 weaned lambs were conducted to evaluate the utilization of ground diets containing varying proportions of grass and legume hay relative to a 90% grain diet. The forage and grain diets were (1) 100% crested wheatgrass hay (CWG); (2) 75% CWGand25% alfalfa hay (AA); (3) 50% CWGand50% AA; (4) 25% CWGand75% AA; (5) 100% AA; and (6) 90% barley and 10% barley straw. Even though apparent digestibility of dry matter (DM) and fiber fractions of AA-containing diets was lower than that of the grain diet and the 100% CWG diet, weight gain was similar for all diets. Consumption of the grain and 100% CWG diet was lower (P < 0.05) than that of the 100% AA diet. Conversion of feed DM to liveweight gain for lambs fed the grain diet was only 4.9 and was lower (P < 0.05) than that of the forage diets, which ranged between 6.1 and 7.0. Dressing percentages of lambs at slaughter for the animals fed the grain and 100% AA diet were 45.0 and 43.2%, respectively, which were higher (P < 0.05) than that of animals fed the CWG-containing diets. These data suggest that inclusion of AA in CWG diets did not result in the expected positive associative effect on growth and feed efficiency in sheep. Key words: Sheep, crested wheatgrass, alfalfa, digestibility, growth

Eating and ruminating activities of cattle fed alfalfa or orchard-grass harvested at two stages of maturity

Four Hereford heifers (mean weight, 371 kg; SD, 17) were fitted with esophageal fistulae and used in an experiment designed as a 4 × 4 Latin square to determine the effects of species and stage of maturity of forage on eating and ruminating activities. Heifers consumed an average of 5.45 kg d−1 of DM from (1) alfalfa, 10% bloom (21% CP, 37% NDF); (2) alfalfa, 50% bloom (16% CP, 47% NDF); (3) orchardgrass, anthesis (17% CP, 56% NDF); and (4) orchardgrass, post-anthesis (14% CP, 59% NDF). Time spent eating was similar for all forages (360 min d−1; P > 0.05). This resulted in alfalfa NDF being subjected to more chewing (167.8 vs. 112.2 min kg NDF−1; P = 0.001). More DM was solubilized during eating from alfalfa than from orchardgrass (38.1 vs. 27.0%; P = 0.001), but less saliva was added per gram of DM (1.94 vs. 3.09 g; P = 0.001). Advanced stage of maturity of both forage species decreased solubilization of DM (28.1 vs. 37.0%; P = 0.002) and increased saliva added per gram of DM (2.28 vs. 2.74 g; P = 0.001) during eating. Rumination time was similar (312 min d−1; P > 0.05) for animals fed alfalfa and orchardgrass. Consequently, rumination chewing per kilogram of alfalfa NDF was greater (140.8 vs. 98.3 min; P < 0.01). More time was spent ruminating late- vs. early-cut forage (348 vs. 276 min d−1; P = 0.04). Results indicate that characteristics of grass and legume hays harvested at similar physiological stages of maturity have little effect on chewing behavior of cattle fed restricted amounts of DM. Despite similar times spent eating and ruminating, the effects of chewing vary with species of forage and stage of maturity. Key words: Cattle, mastication, rumination, forage quality

The supplementary value of forage legume hays in sheep feeding: feed intake, nitrogen retention and body weight change

Supplementation with forage legumes could be a sustainable way of improving the feeding value of poor quality crop residues especially to the resource poor African smallholders. Thus, the potential of Desmodium intortum, Macrotyloma axillare and Stylosanthes guianensis in improving the utilization of a basal diet of maize stover by sheep was assessed in a feeding trial. Maize stover used in this experiment was high in lignocellulosic cell-wall constituents and very low in CP. S. guianensis hay contained higher CP and lower NDF, ADF, and lignin contents than D. intortum and M. axillare hays. According to animal responses, under the conditions of this experiment, S. guianensis was superior to the other two legumes in improving the feeding value to sheep of maize stover based diets. M. axillare was found to be inferior. In general, 250 g of S. guianensis and 350 g of D. intortum hays per day per sheep (18.2 kg Lwt ± 1.2) were found to be optimum levels of supplementation to maize stover. At these levels of supplementation modest levels of bodyweight gain were achieved. It is suggested that the two legumes are useful to bridge the gap in feed supply in areas where livestock depend on poor quality crop residues during the dry season.

Wynn cassia (Cassia rotundifolia cv. Wynn) improves the feed intake and liveweight gain of cattle fed poor quality native pasture

The feeding value for cattle of Wynn cassia hay (Cassia rotundifolia cv. Wynn) was assessed by measurement of dry matter intake (DMI) and average liveweight daily gain (ADG) of yearling steers fed chaffed diets of native pasture hay (0.44% N) that included 0, 10, 25, 50, or 80% of cassia hay. The cassia hay was obtained after seed harvest and, so, was of relatively poor quality (1.10% N, 70% stem). For comparison, lucerne hay (Medicago sativa cv. Trifecta) (2.42% N) treatments were also fed with native pasture hay at the same dietary legume proportions. The experiment was conducted over an 80-day period. Cattle fed only native pasture had low DMI (2.9 kg/head.day) and ADG (0.012 kg/head). DMI increased curvilinearly and ADG increased linearly with the proportion of cassia in the diet. Both DMI and ADG were significantly (P<0.05) increased when 50% cassia was fed (to 5.24 kg/head.day and 0.210 kg/head, respectively), while only 25% lucerne was needed to obtain significant increases in both parameters (to 5.69 kg/head.day and 0.310 kg/head). The poorer response to increasing dietary legume measured with cassia diets was not unexpected given that it had been cut at a more mature stage of growth. However, when the responses were examined against a common index of feed quality (protein content), both legume hays gave similar responses. Despite its relatively poor quality, the cassia hay was readily eaten at levels up to 50% of the diet, and improved both DMI and ADG. Our results suggest that cassia successfully introduced into native pasture will improve the liveweight performance of grazing cattle.

The Effect of Improved Management on the Yield and Nitrogen Content of Legume Hay/Barley Crop Rotations in West Asia

AbstractIn the light of growing governmental support in west Asia and north Africa for policies which either discourage cereal monoculture or encourage fallow replacement by farmers, two experiments were conducted in northern Syria. These were designed to evaluate and quantify the effect of agronomic interventions on the productivity and nitrogen content of legume hays, and the subsequent residual effects of these interventions on the yield and nitrogen content of a following barley crop. Quantitative estimates of the residual effects of legume hays, when grown under rainfed conditions, on the N uptake of barley are rarely available for the region at large.The major management effects on the productivity of legume hays were the addition of phosphate fertilizer and a reduction in row spacing. Positive residual effects on the yields of following barley crops were shown to be small but not insignificant. They could be considered to be important influences in the sustained production of barley in legume hay‐barley crop rotations.It is suggested that the results give further positive evidence that farmers in west Asia will not resist the introduction of improved crop rotations including legumes in place of their current fallow‐barley or continuous barley crop sequences.

Winter and Spring Habitat Use by Gray Partridge in New York

We compared winter and spring habitat use and home ranges of radio-tagged gray partridge (Perdix perdix) in established (1982) and translocated (1982 and 1983) populations in New York. Both populations selected grain stubble during winter and spring. Birds in the established range also used farmsteads in winter. By late spring, both populations selected idle uplands, and partridge in the translocated range also used legume hay. Home ranges were variable (x=82-672 ha), and did not differ by season (P>0.05). We suggest that a lack of preferred grain stubble in winter may limit populations in the established range. Populations in the translocated range may be limited by the availability of nesting cover

Clinical Nutrition of Adult Horses

Horses suffering from trauma, sepsis, and severe burns need 12% to 16% of protein (dry matter basis) in their diet. Since reduced appetite may be a problem, relatively energy dense (greater than 2 Mcal DE/kg) feeds should be offered. In hepatic failure, maintenance protein requirements (8% on a dry matter basis for adult horses) should be met with feeds that are high in short branched-chain amino acids and arginine but low in aromatic amino acids and tryptophan (for example, milo, corn, soybean, or linseed meal) in addition to grass hay. Vitamins A, C, and E should also be supplemented. In cases with renal failure, protein, calcium, and phosphorus should be restricted to maintenance or lower levels. Grass hay and corn are the best feeds for horses with reduced renal function. Do not offer free-choice salt to horses with dependent edema from uncompensated chronic heart failure. Following gastrointestinal resection, legume hay and grain mixtures are the feeds of choice. Horses with diarrhea should not be deprived or oral or enteral alimentation for prolonged periods of time. Liquid formulas may be used if bulk or gastrointestinal motility are a problem. Apple cider vinegar and a high grain diet may reduce the incidence of enteroliths in horses prone to this problem. Pelleted feeds will reduce fecal volume and produce softer feces for horses that have had rectovaginal lacerations or surgery. Horses with small intestinal dysfunction or resection should be offered low residue diets initially, but long-term maintenance requires diets that promote large intestinal digestion (alfalfa hay, vegetable oil, restricted grain). Geriatric horses (greater than 20 years old need diets similar to those recommended for horses 6 to 18 months old.

Crop Production During Conversion from Conventional to Low‐Input Methods

AbstractA 5‐yr cropping system experiment was initiated in 1981 to study transition from a conventional agricultural system using pesticides and fertilizers to a low‐input system. The site was primarily Comly silt loam (fine‐loamy, mixed, mesic, Typic Fragiudalf) with 12% Berks shaly silt loam (loamy‐skeletal, mixed, mesic, Typic Dystrochrept), and a small area of Duffield silt loam (fine‐loamy, mixed, mesic, Ultic Hapludalf), in Berks County, eastern Pennsylvania. Three 5‐yr rotations were compared. A conventional corn (Zea mays L.)‐soybean [Glycine max (L.) Merr.] rotation (designated “conventional”) was compared to two low‐input rotations which utilized oat (Avena sativa L.), red clover (Trifolium pratense L.) and winter wheat (Triticum aestivum L.), in addition to corn and soybean. One low‐input rotation used cattle manure as a nutrient source and produced forage crops in addition to cash crops (designated “low‐input/livestock”), while the other used legume crops as a nutrient source, and produced a cash crop every year (designated “low‐input/cash grain”). Corn grain yields in the low‐input systems were 75% of conventional in 1981 to 1984, but yields were not significantly different in 1985. Weed competition and insufficient N limited low‐input corn yields during the first 4 yr. Soybean yields in the low‐input systems were equal to or greater than conventional all 5 yr. It is concluded that a favorable transition from input‐intensive cropping to low‐input systems is feasible, but only if crop rotations are used which include crops that demand less N and are competitive with weeds, such as small grain, soybean, or legume hay. Corn should be avoided for the first 3 to 4 yr.

MECHANICAL AND CHEMICAL CONDITIONING OF HAYS

In 1982 and 1983, six field trials and three controlled environment studies were conducted (1) to determine if the drying agent potassium carbonate (K2CO3), alone or in combination with mechanical conditioning, accelerated the drying of field hay more than conventional mechanical conditioning alone; (2) to gauge the reliability of K2CO3 as a drying agent; (3) to contrast the effectiveness of K2CO3 on alfalfa (Medicago sativa L. and M. media Pers.) relative to other legumes; and (4) to compare the sensitivity of K2CO3 action to controlled irradiance, temperature and relative humidity (RH). Relative to unconditioned hay, mechanical conditioning alone reduced field drying time to safe baling moisture in four of the six trials, while chemical (K2CO3) conditioning alone reduced field drying time in three of the six trials. Hay treated with a combination of mechanical and chemical conditioning typically dried faster than either process alone. Heavy windrows and poor drying conditions lessened the value of either conditioning treatment. In single-stem drying tests conducted under controlled environmental conditions, K2CO3 significantly accelerated drying in two alfalfa cultivars, as well as in sainfoin (Onobrychis viciifolia Scop.), red clover (Trifolium pratense L.), alsike clover (T. hybridum L.), and sweetclover (Melilotus alba Desr.). Potassium carbonate reduced time to reach 20% moisture by about 50%, with some variation in responsiveness among legumes. Increasing irradiance from 100 to 150 W m−2 did not influence response to K2CO3. Increasing temperature increased responsiveness to K2CO3. Increasing RH from 45 to 70% slightly increased the effectiveness of K2CO3, particularly at the lower level of irradiance. Potassium carbonate can be an effective tool in accelerating field drying of legume hays, when used in conjunction with mechanical conditioning. However, the utility of either mechanical or chemical conditioning depends on both drying conditions and harvest management. Conditioning will not compensate for cool, cloudy weather, or for heavy dense windrows. Potassium carbonate was shown to accelerate drying on all tested legumes, and to be most effective when temperature was high.Key words: Field hay drying, mechanical conditioning, potassium carbonate, alfalfa

Apparent digestibility of nitrogen and nitrogen retention of forages fed to steers in metabolism stalls.

Holstein steers in metabolism stalls were utilized to determine apparent digestibility of N (DN), N retention (NR) expressed as a percentage of total N consumed, and Mcal/kg digestible energy (DE) when diets of seven different classes of forages were fed. The best predictive equation for digestibility of N in the 153 forages studied was DN(%) = -98.1065 + 11.4724 (%CP) + 41.4475 (DE) - .1498 (%CP)2 - 1.2541 (DE)2 - 1.9309 (CP) (DE), with R2 = .74 and Sy.x = 8.63, where %CP is the percent crude protein of the forage. The best predictive equation for DN of sorghum silages, corn silages, legume hays and temperate grass hays contained both %CP and DE as predictor variables. The best predictive equations for DN of sorghum-sudan and bermudagrass hays contained only %CP and (%CP)2 as predictor variables. The predictive equation for DN of 14 alfalfa hays involved only the linear relationship to %CP. The best scheme for predicting NR as a percentage of N consumed in 116 forages was a combination of three equations as follows: 1) NR(%) = -47.0797 + 6.4733 (%CP) - .1542 (%CP)2 for forages, where DE = less than 2.42 Mcal/kg; 2) NR(%) = -67.6306 + 10.1354 (%CP) - .2726 (%CP)2, where DE = 2.42 - 2.87 Mcal/kg; and 3) NR(%) = 28.3458 + 4.4722 (%CP) - .1263 (%CP)2, where DE = greater than 2.87 Mcal/kg; R2 = .42 and Sy.x = 14.86.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of dietary forage proportion on digestive function in maintenance-fed beef cows. 3. Bermudagrass and clover hays.

Five crossbred beef cows (Hereford X Angus, 438 kg), cannulated in the rumen and duodenum, were used in a Latin square experiment to determine the effects of dietary proportions of bermudagrass (B) and clover (C) hays (0: 1, .25: .75, .5: .5, .75: .25 and 1: 0) on digestive function. Feed intake was 85% of ad libitum intake of B alone (1.35% of body weight). Bermudagrass contained 1.88% nitrogen (N), 79.6% neutral detergent fibre (NDF) and 5.2% acid detergent lignin (ADL), and C contained 2.30% N, 55.3% NDF and 6.3% ADL. Molar proportion of acetic increased linearly while propionic acid moved in the opposite direction as B replaced C (P less than .05). Mean particle size of duodenal digesta increased linearly (P less than .05) as B increased, but specific gravity of particles was constant (P greater than .10). Fluid passage rate decreased while volume increased linearly with increasing B (P less than .05) so that ruminal fluid outflow rate increased quadratically (P less than .10). Particulate passage rate ranged from 3.0 to 3.4% h. Apparent ruminal organic matter (OM) digestion was 69.0, 54.0, 53.0, 49.1 and 49.7% for 0, 25, 50, 75 and 100% B, respectively, decreasing quadratically as B rose (P less than .05). Postruminal OM digestibilities as percentages of intake and available OM changed quadratically (P less than .05) as dietary B increased, causing total tract OM digestion to decrease linearly (P less than .05; 73.8, 66.4, 63.1, 60.3 and 58.2% for 0, 25, 50, 75 and 100% B diets, respectively). Duodenal microbial-N flow increased quadratically with increasing B (P less than .05), being 45, 108, 103, 105 and 101 g/d, and microbial growth efficiency increased quadratically as well (P less than .05). True ruminal N disappearance ranged from 69.0 to 79.4% and was not affected by diet (P greater than .10). Ruminal digestibilities of fibre fractions were similar to OM. Little digestive function benefit was achieved by mixing warm season grass and legume hays in diets of maintenance-fed beef cows.

Digestibility, intake and mineral utilization of combinations of grasses and legumes by lambs.

Defined mixtures of two grass (orchardgrass, perennial ryegrass) and two legume (alfalfa, red clover) hays, harvested in two cuttings in 2 yr, were fed in digestibility, intake and mineral balance trials to wether lambs. Each mixture was fed in ad libitum amounts to six crossbred wether lambs weighing 35 to 45 kg. The effect of increasing proportion of legume in mixtures on dry matter digestibility (DMD), neutral detergent fiber digestibility (DNDF) and digestible dry matter intake (DDMI) differed with species combination. For all combinations, a quadratic regression (P less than .05) for DMD and DNDF indicated a small, negative associative effect for mixtures of grasses and legumes compared with pure species. Dry matter intake (DMI) showed a quadratic increase with level of legume inclusion, indicating a positive associative effect. The observed increase of DMI was approximately 6 to 7% over predicted values with 25 or 50% legume in the mixture. Intake of NDF also showed a quadratic response to level of legume, but lambs tended to eat to a fairly constant intake of 42 to 43 g NDF/kg wt.75. Mineral utilization (apparent absorption, retention) differed (P less than .05) with cutting but not species combination, and generally improved with increasing legume content in the mixture. With the exception of calcium retention (negative quadratic effect), there was little evidence for significant associative effects between grasses and legumes in mineral utilization.

OXALATE CONCENTRATION IN FEEDS AND ITS METABOLISM BY PONIES

Total oxalate and calcium determinations were made in 200 feed samples. Legume hays contained more oxalate than legume-grass, grass (including brome and timothy), native grass and cereal hays (P < 0.05). Grass, native and cereal hays contained low calcium and low to moderate oxalate concentrations. Based on molar ratios and the assumption of preferential binding of calcium by oxalate, it was estimated that about 25% of calcium in legume and legume-grass hays could be bound by oxalate. Similarly, oxalate might bind 38–44% of the calcium contained in native grass and cereal hays and would exacerbate the low calcium content of these hays. Only one hay, a kochia, had oxalate concentrations (3.2%) known to cause acute toxicity in livestock. Oxalate concentration was positively correlated to calcium concentration (r = 0.69). Chopped alfalfa, oat, brome, and slough hay and pelleted alfalfa, oat and barley hays were fed to ponies in two separate Latin square experiments. Apparent oxalate digestibilities were determined to be 48–88%. Cereal hays had the highest apparent oxalate digestibilities in both trials (73–88%) (P < 0.05). Key words: Oxalate, calcium, forages, ponies

N tau-methylhistidine--feed and duodenal content and ruminal degradation.

N tau-methylhistidine (NMH) concentrations were determined in acid hydrolysates of 12 common feedstuffs for ruminants, and duodenal digesta from steers fed alfalfa haylage and high-moisture corn. For six species of grass hays, NMH concentrations ranged from nondetectable (ND; less than .1 nmol/g dry matter) to .6 nmol/g dry matter. Two legume hays had NMH concentrations of .9 and 2.0 nmol/g dry matter, respectively. For corn silage, high-moisture corn, beet pulp and soybean meal, NMH concentrations were 1.3, 1.1, 1.5 and 2.2 nmol/g dry matter, respectively. Duodenal digesta NMH concentrations ranged from ND to 1.2 nmol/g dry matter. When pure NMH (1 mM) was incubated with rumen fluid in vitro for 8 h, only 14% was degraded while leucine (1 mM) was totally degraded. From the feedstuffs used in this study, results show that exogenous (dietary) NMH is not a concern in skeletal muscle protein turnover studies in cattle using urinary NMH excretion because it can be calculated that potential NMH intake from the preceding feedstuffs would be less than 1% of normal urinary excretion and that ruminal microbes are not a potential source of NMH. NMH was resistant to in vitro ruminal degradation. The in vitro ruminal NMH degradation results suggest that when feedstuffs containing at least 15 nmol/g dry matter are fed (far greater than values observed in this study) a significant proportion of urinary NMH would arise directly from exogenous sources and would invalidate the use of this technique in assessing protein turnover in cattle.

The effect of lucerne supplementation on the intake of straw and the digestion kinetics of straw and lucerne

Leguminous crops represent a potentially valuable source of protein and energy for the ruminant. They promote higher levels of microbial activity in the rumen than most other feeds (Agricultural Research Council, ARC, 1984), probably because of their content and rate of release of nutrients. Thus, they may be useful supplements for low quality roughages. Levels above 0.15 - 0.20 long or chopped legume hay included in low quality roughage based diets result in a reduction in the intake of the basal roughage (Lane, 1982; Minson and Milford, 1967; Mosi and Butterworth, 1985; Siebert and Kennedy, 1972). This substitution effect may be due to a rumen physical limitation and/or a limiting nutrient supply for the rumen micro-organisms. The objective of this work was to study the effect of supplementing straw with lucerne pellets on the digestion kinetics and intake of the dietary components.

Wetting Effects on the Yield and Quality of Legume and Legume‐Grass Hays1

AbstractInformation is needed on rain effects on yield and quality of legume and legume‐grass hays. A field study was conducted on a Piano silt loam soil (fine‐silty, mixed, mesic, Typic Argiudoll) to evaluate rain effects on the yield and chemical composition of hays from pure swards of alfalfa (Medicago sativaL.), red clover (Trifolium pratenseL.), and birdsfoot trefoil (Lotus corniculatusL.) and mixtures with smooth bromegrass (Bromus inermisLeyss.). Plots for the factorial experiment (each 1.1 by 7.6 m) were arranged in a split plot design with legume species and pure or mixed sward type combinations as main plots and wetting treatments as the sub plots with four replicates. Wetting treatments consisted of field drying to 750 g dry matter (DM)/kg of total mass (TM) or more without rain or exposure to rain or artificial wetting during drying. Samples were collected just after cutting and after hay curing for quality analysis. Rain reduced the proportion of leaf by 109 and 151 g/kg for alfalfa and birdsfoot trefoil, respectively, but did not affect red clover leaf content. Rain increased DM loss by as much as 154 g/kg (pure alfalfa) but did not affect DM loss for the birdsfoot trefoil‐grass mixture. Legume‐grass hays generally had more neutral detergent fiber (NDF) and lower N and in vitro dry matter disappearance (IVDMD) concentrations than pure legume hay. Rain or wetting reduced IVDMD by from 13 g/kg (birdsfoot trefoil‐grass) to 64 g/kg (alfalfa). Except for Ca, which was reduced in some cases, rain or wetting did not affect mineral concentrations in dry hay. The presence of grass in the sward provided consistent advantage in hay drying only for red clover. Rainfall increased DM losses during hay curing except for the grass‐dominated birdsfoot trefoil mixture. Rain or wetting reduced hay quality by reducing IVDMD and increasing NDF concentration. Nitrogen, P, K, and Mg concentrations were not greatly affected by rain or wetting.

Wetting and Maturity Effects on Mineral Concentrations in Legume Hay1

AbstractWetting by rainfall during field drying of legume hay reduces forage yield and in vitro dry matter disappearance. Field experiments were conducted to evaluate wetting effects on mineral composition of alfalfa (Medicago sativaL.) and red clover (Trifolium pratenseL.) hay. Three and one‐half kg samples of each species, grown on Plano silt loam soil (fine silty, mixed, mesic Typic Argiudolls) and harvested at early and late maturity stages, were placed on wire screens and allowed to dry without wetting or were exposed to natural or artificial wetting in 1980 and 1981. A completely random design was used with three replicates in 1980 and two in 1981. In 1980, 25 mm of water was applied using sprinklers to hay wetted during drying. In 1981, hays wetted during and after drying were exposed to 41 and 62 mm of natural precipitation, respectively. Late maturity (fullto late‐bloom) forage was lower in P, K, Ca, Mg, and S than early maturity forage (early bud to first flower) of the same species. Artificially wetted and well cured hay did not differ significantly in concentrations of P, K, Ca, Mg, or S in 1980. Precipitation totaling 62 mm on dry early to late‐bud alfalfa hay reduced the K concentration from 28.1 to 15.5 g kg−1, indicating substantial leaching. The same treatment increased P concentration from 4.1 to 5.5 g kg−1, increased Ca from 13.0 to 19.7 g kg−1, and increased Mg from 4.2 to 5.0 g kg−1. Late‐bud and first‐flower red clover responded similarly when subjected to the same treatment. Late‐bloom alfalfa, exposed to 41 mm of precipitation during drying had 2.4 g kg−1of P, 15.9 g kg−1of K, 8.2 g kg−1of Ca, 1.9 g kg−1of Mg, and 1.6 g kg−1of S compared with 2.5,20.8, 11.5,2.5, and 2.2 g kg−1, respectively, for the same minerals in hay cured without wetting. Based on these data, the impact of wetting during hay curing on concentrations of P, Ca, Mg, and S was smaller than wetting effects on forage yield and in vitro dry matter disappearance. Wetting reduced K concentration to a greater extent than it reduced the other minerals studied. Alfalfa forage was consistently higher in S and lower in Mg than red clover forage of similar maturity.