Alfalfa Pasture Research Articles

Reproductive performance of Rasa Aragonesa ewes mated on lucerne ( Medicago sativa cv. aragon) pastures

Coumestrol and small amounts of isoflavones were present in lucerne (alfalfa) but only traces were found in ryegrass ( Lolium sp.) pastures. A mean of 27.1 mg coumestrol/d was consumed by the ewes on lucerne pastures. Ovulation rate (1.5) of ewes flushed and mated on lucerne was significantly depressed by 20% relative to ewes mated on ryegrass (1.7). However, neither barrenness nor embryonic losses were significantly increased when ewes were fed on lucerne cv. Aragòn. The results suggested adverse effects on ovulation rate of ewes grazing lucerne pastures prior to and during joining that could negatively affect lambing performance.

Predicting the profitability of alfalfa silage and pasture feeding systems for Holstein steers.

Data from two research trials were used as inputs to a model to project the return to capital of two-phase alfalfa silage and pasture feeding systems for Holstein steers. This approach presents a methodology for applying research data over widely varying conditions. Cattle received a 40% (High = H), 22% (Medium = M), or 8% (Low = L) alfalfa silage diet or grazed an orchardgrass/ryegrass pasture (Pasture = P) during Period 1. During Period 2, cattle consumed a 90% concentrate diet until ultrasonic attenuation predicted that the longissimus muscle contained a small degree of marbling. All systems produced similar carcass grades, so profitability differences resulted from relationships between feed requirements, cost of feed, and cost of time. Cattle grazed on pasture yielded a higher return to capital during Period 1 and over the entire feeding system. Among the other systems, L returned more to capital during Period 1, but over the entire feeding system additional silage returned more when silage cost was less than $32 per 1.02 t (as fed). Above this cost, the continuous 90% concentrate diet yielded a higher return. Cattle implanted with trenbolone acetate and estradiol returned $60 in Trial 1 and $86 in Trial 2 more per animal than did unimplanted steers.

Management systems for Holstein steers that utilize alfalfa silage and improve carcass value.

Two trials were conducted to evaluate the effect of two-phase feeding systems using alfalfa silage or pasture on the performance and carcass characteristics of Holstein steers. During the growing phase (98 d) of Trial 1, steers received alfalfa silage at either 40, 22, or 7% of the DMI. During the growing phase of Trial 2, steers received alfalfa silage at either 39 or 8% of their DMI (140 d) or grazed an orchardgrass/ryegrass pasture (175 d). During the finishing phase, all steers received a 90% concentrate diet until they reached a small degree of marbling at the 12th rib as predicted by ultrasonic attenuation. In Trial 1, one-half were initially implanted with zeranol and reimplanted with trenbolone acetate and estradiol (TBA+E) after 98 d. In Trial 2, one-half were implanted twice with TBA+E at a 120-d interval. Trial 1 average daily gains (kilograms) for the 40, 22, and 7% alfalfa silage treatments were 1.14, 1.25, and 1.38 in Period 1 (all different from each other at P less than .05); 1.31, 1.34, and 1.19 in Period 2; and 1.25, 1.25, and 1.26 overall. Trial 2 average daily gains (kilograms) for the 39, 8, and pasture treatments were 1.50, 1.71, and .92 for Period 1 (all different from each other at P less than .05); .93, .75, 1.11 for Period 2 (all different from each other at P less than .05); and 1.16, 1.17, and 1.03 overall (pasture different at P less than .05). No consistent effects of diet or implant on carcass characteristics were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiology and effects of nematode infections on beef cow-calf systems of Argentina's western pampas

The epidemiology and the effects of nematode infections on cow-calf systems were followed from 3 weeks before calving to 7 months afterwards. Two groups, each of 15 cow-calf pairs grazed on separate lucerne pastures. Group I (GI) were treated monthly with oxfendazole (4.5 mg kg −1), cows being dosed from calving and calves starting 45 days later. Animals in Group II (GII) were not treated. The egg output of the cows was very low. An increase was recorded 2 months after parturition, consisting mainly of Ostertagia spp. The egg output and worm burdens of calves remained low until late summer and reached a peak in autumn. Ostertagia, Cooperia and Haemonchus were the main genera recovered from slaughtered calves. The pasture contamination and tracer calf worm counts remained consistently low until autumn when they began to increase. Inhibited early fourth stage larvae of Ostertagia were recovered during spring. After calving, the live-weight gains (LWG) of treated GI cows were significantly higher ( P < 0.004) than those of GII cows, whereas the LWG of GI calves were significantly higher during December ( P < 0.037) and March ( P < 0.029) than those of GII calves. There were significant ( P < 0.04) cumulative LWG responses between GI and GII calves with no differences in cow cumulative LWG at the end of the trial. For spring-born calves, these results suggest that strategic deworming programs in cow-calf systems may produce benefits.

The effect of N, P, S fertilizer, temperature and precipitation on the yield of bromegrass and alfalfa pasture established on a Luvisolic soil

This study was conducted over a 12-yr period to determine the effect of N, P, and S (elemental) fertilizers on yield of bromegrass (Bromus inermis Leyss.) and alfalfa (Medicago media Pers.) pasture established on a Gray Wooded, Luvisolic soil (Waitville loam) in northeastern Saskatchewan. Nitrogen fertilizer was applied at 0, 45, and 90 kg N ha−1 in combination with phosphate fertilizer applied at 0 and 20 kg P ha−1. Two additional treatments combined 90 N + 20 P (kg ha−1) with 23 S and 45 S (kg ha−1). In the first 3 yr of the study, only the application of N increased yields, from 2.54 to 3.45 t ha−1. The combination of time (years 1978–1980) and N fertilizer applied up to the rate of 90 kg N ha−1 resulted in a reduction in percentage alfalfa in the sward from 30.9 to 3.8% (Yr × N interaction). Over the 12-yr period, N increased average herbage yield from 1.99 to 2.95 t ha−1; P, from 2.23 to 3.05 t ha−1 and S from 3.48 to 4.19 t ha−1, respectively. The interaction effects of N × Yr, P × Yr and S × Yr all were significant indicating a wide range of response to the fertilizer elements among years. Herbage yield was positively related to total precipitation and negatively to mean maximum temperature for the months of May, June and July. The highest yield (7.49 t ha−1) was obtained with fertilizer (90N-20P-23S kg ha−1), 220 mm of rainfall (May, June and July) with an average maximum temperature of 19.7 °C. The lowest yield (0.84 t ha−1) was obtained with a control (no fertilizer), 160 mm of rainfall and average maximum temperature of 25.2 °C (fertilizer × temperature-precipitation interaction). Results of this study suggest that a rise in average temperature without a corresponding increase in precipitation, would produce a significant drop in bromegrass herbage yield. Key words: Pasture, nutrients, alfalfa, bromegrass, temperature, precipitation

Effects of an integrated control programme with ivermectin on growth, carcase composition and nematode infection of beef cattle in Argentina's western pampas

The effect of previous pasture management and ivermectin treatment on gastrointestinal parasitism, weight gain and carcase composition of steers was studied in the semiarid Pampeana region of Argentina from April 1986 to April 1987. Three groups, each of 15 weaned calves, were grazed on separate lucerne pastures. Group 1 control calves, which grazed paddocks previously grazed by nematode-infected weaners and yearlings with a high nematode egg output, were only medicated when heavy parasitism was recorded. Group 2 calves, which grazed paddocks previously infected by steers at least two and a half years old with low nematode egg output, were treated strategically with ivermectin. Group 3 calves, which grazed on ‘clean’ paddocks, were treated monthly with ivermectin. Group 1 calves showed heavy parasitism and parasitological parameters were higher than in groups 2 and 3. The liveweight gain responses of groups 2 and 3 were significantly greater than those of group 1 (P < 0 · 001) during autumn, winter and early spring. At the end of the study when cattle reached market condition, the liveweight gains of groups 2 and 3 were 74·1 and 81·9 kg, respectively, greater than group 1. Carcase analyses showed significantly greater weight and killing-out percentages in groups 2 and 3 than in group 1. Reduced total bone, muscle and fat weights were observed in group 1.

Acidification of soil associated with lupins grown in a crop rotation in north-eastern Victoria

Soil pH decline and net acidification inputs were determined for a long-term crop rotation experiment at Rutherglen in north-eastern Victoria. The rotations utilized were continuous wheat (WW), a 1 : 1 wheat-lupin sequence (WL) and continuous lupins (LL), and each rotation was cropped from 1975-1989. The soil at the site had an initial pH (0.01 mol/LCaCl2) of 6.0 (0-10 cm depth), sandy loam texture, and had a past use of grape vines and then lucerne pasture. The soil pH (0-10 cm) declined for each rotation with time (1977/78-1988/89), decreasing by about 0.8 units for WW and further decreasing with the inclusion of lupin in the rotation. Compared with the WW soil, the WL soil pH was 0.7 and 0.4 units lower at 5-10 cm and 10-15 cm depth and the LL soil pH was 1.0 and 0.8 units lower at 5-10 and 10-15 cm depth. There was no difference in pH between WW and WL below 20 cm depth, but the LL soil had a significantly lower pH to 40 cm depth. Acidification rates were calculated for the period of cropping and for the 3 rotations, with rates of 3.22, 4.11 and 5.26 kmols H+/ha.yr as net acid input for WW, WL and LL rotations. These values represent a rapid rate of soil acidification. The removal of alkalinity in grain accounted for between 15-21% of the overall calculated acidification rate for the 3 rotations. Therefore, it is likely in this cropping system that the acidification largely results from progressive nitrate leaching.

Induction of tall fescue toxicosis in heat-stressed cattle and its alleviation with thiamin.

Livestock grazing endophyte (Acremonium coenophialum)-infected tall fescue (Festuca arundinacea Schreb. cv. Kentucky 31) at high ambient temperatures may suffer from fescue toxicosis. Adult Angus cows (Bos taurus) were fed 0 to 1 kg/d of 70% infected tall fescue seed containing about 4.4 g of loline alkaloids in factorial combination with thiamin at 0 or 1 g/d. Cows assigned to the zero level of tall fescue seed received a supplement of equivalent energy and protein. Ingestive behavior was measured at 1330 to 1430 EDT during two 4-d periods in two consecutive weeks in August on alfalfa (Medicago sativa L.) pastures using a tethered grazing system. Alfalfa intake per measured grazing session of cows given tall fescue seed declined linearly (P less than .01) as air temperatures during grazing increased above 25 degrees C, largely because of shorter grazing meals. Thiamin increased alfalfa intake per measured grazing session by extending grazing time. Alkaloids in ingested endophyte-infected tall fescue induce thiamin deficiencies in cattle that result in symptoms of tall fescue toxicosis.

Simulation of lean lamb production systems.

A series of simulations were performed to evaluate the effects of mature size (WMA; 60, 70, 80 and 90 kg), slaughter weight (SW; 55, 60 and 65 kg) and three diets fed to feedlot lambs. Rations included a traditional diet (C2L) or placing weaned lambs on alfalfa for either 30 (A30) or 60 (A60) d before placing them on the C2L diet (A30-C2L and A60-C2L). Two lamb pricing schemes were used in the financial analysis of the biological results: sale price based on weight with or without adjustment for carcass fat. Placing lambs on alfalfa pasture increased ownership by 22 d on average compared to C2L. As WMA and SW increased, ownership increased from 3 to 11 d. Across nutritional treatments, fat decreased by 5.8 to 9.0% as WMA increased from 60 and 90 kg. When market lambs were priced on weight, net returns per lamb were greatest for A30-C2L or A60-C2L ($2.34 and $5.21, respectively above C2L) and for greater SW ($4.77 and $7.16 greater for SW 60 and 65 kg than for SW 55). The combination WMA of 90 kg, a SW of 65 kg and nutritional treatment of A60-C2L proved most profitable. However, when sale price was discounted for excessive fat content, the combinations WMA of 60 or 70 with a SW of 65 and A60-C2L were most profitable. The rank correlation between biological efficiency (weight gain/dry matter feed consumption) and net return, when sale price was based on weight, was found to be -.51. This was because lambs slaughtered at lighter weights had high biological efficiencies but low net returns due to a negative price margin. With negative price margins but positive feeding margins, net returns are greatest for heavier, fatter lambs fed longer.

The influence of the application of grass herbicides on the production of dryland medic and lucerne pastures in the Rûens area of the southern Cape

Reports on a trial which was conducted over a period of three seasons in which the advantages of the removal of grass weeds from dryland lucerne and medic pastures determined. Two herbicide treatments, an unsprayed control and a grass herbicide treatment were compared for three seasons. Illustrates with graphs and a table; A trial was conducted over a period of three seasons in which the advantages of the removal of grass weeds from dryland lucerne and medic pastures were determined. The pastures were grazed at four stocking rates, i.e. 6, 8, 10 & 12 non-lactating merino ewes and wethers/ha. Two herbicide treatments, an unsprayed control and a grass herbicide treatment were compared for three seasons. The herbicide treatment consisted of two applications, one each of fluazifop-butyl and propyzamide, respectively, during the first two seasons. On the lucerne pastures the removal of the grass weeds resulted in an increased wool production and, to a lesser extent, ADG, which also resulted in an economic advantage. On medic pastures, however, the removal of the grass weeds did not result in any animal production or economic advantage. Herbicide treatment, however, did result in a higher medic pod yield, which should increase the productive lifespan of these pastures.Language: English Keywords: Economic analysis; Fluazifop-butyl; Merino sheep; Pastures; Propyzamide; Wool production; adg; animal production; dryland; fluzifop-butyl; grass; lucerne; treatments; weeds; yield; production; grasses; herbicides; southern cape; south africa; ruens; stocking rates; medicago sativa; medicago truncatula

Influence of pre- and postpartum nutrition on growth of goat kids

Effects of change in nutritional treatment in grazing goats from 4 weeks before parturition to weaning of kids at 12 weeks, on doe weight, milk yield, kid birth weight, mortality and growth up to weaning were studied. Two groups of a mixture of feral and crossbred goats grazed on barrel medic ( Medicago truncatula), blue crowfoot ( Erodium crinitum) and lucerne ( Medicago sativa) pasture or sparse, heavily grazed rye grass ( Lolium perenne). These pastures are designated “high” and “low”, respectively. “Low” plane feral and crossbred goats lost 21 and 13% in liveweight, respectively; had significantly lighter kids at birth (2.9 vs. 3.2 kg), lower kid survival (64 vs. 86%), lower milk yield by 24% and lower daily kid growth (192 vs. 225 g) than the high group. However, milk yield was not significantly different in early lactation in spite of significant differences in goat weights. Kid survival was mainly dependent on birth weight with maximum mortality occurring at or below a birth weight of 2.5 kg and a Chill Index around 1000 kJm −2 h −1. Kid growth was also dependent on birth weight followed by maternal nutrition, breed and sex. Birth weight had more than twice the effect of milk intake and more than 10 times the effect of breed on kid growth. When kids were compared at the same birth weight, there was no significant effect of breed on growth.

Studies of wool growth responses to 2-hydroxy-4-(methylthio) butanoic acid, Alimet, an analogue of methionine

An analogue of DL-methionine, Alimet, was evaluated for its commercial potential for increasing wool growth in Merino sheep in pen and grazing experiments. This was done by administering Alimet as a drench, in drinking water, or via rumen or abomasal fistula, and measuring wool growth rate and plasma methionine concentrations. In vivo data indicated that significant wool growth responses (23-35%) to Alimet as a drench or in drinking water occurred at low rates (estimated 5-6 g/sheep.day) of basal wool production when sheep were fed a lucerne diet to maintain liveweight. At higher rates of clean wool growth (10-12 g/sheep.day) when sheep were eating above-maintenance diets (lucerne ration or pasture), Alimet treatment was associated with variable and reduced response. A significant (P&lt;0.05) negative correlation (r2 = 0.699, n = 11) between wool growth responses (x � s.d. = 0.11 � 0.067) to the 3 mL dose rate of Alimet and wool growth in control treatments (y �: s.d. = 0.70 � 0.202) confirmed the above trend. Four hours after administration of Alimet via either rumen or abomasal fistula, comparative plasma concentrations of methionine, 28 and 168 �mol/L respectively, suggest that Alimet is susceptible to degradation in the rumen. The corresponding values for DL-methionine, via either rumen or abomasal fistula, were 64 and 350 �mol/L, respectively. The small rises (40%) in plasma methionine values associated with significant increases in wool production indicate that a dose of 3 mL is as effective as 4 mL of Alimet when the basal nutritional regime is limiting. While administration of Alimet in drinking water during dry seasons is possible, the profitability of supplementation would need to be tested further.

Steer Performance on Birdsfoot Trefoil and Alfalfa Pasture in Central Georgia

Steer Performance on Birdsfoot Trefoil and Alfalfa Pasture in Central Georgia

Readjusting the water balance to combat dryland salting in southern Australia: Changing the hydrology of a texture contrast soil by deep ripping

Dryland salting is one of the biggest problems in dryland agriculture in southern Australia. It has been caused by the replacement of the original, deep-rooted, perennial trees and shrubs with shallow-rooted, annual crops and pastures. The accompanying decrease in evapotranspiration has caused an increase in deep infiltration to the groundwater. The rising groundwater has in many areas been salinised through mobilisation of salts previously stored in the regolith above the groundwater table. The effect on agriculture where such saline groundwater rises to or close to the surface is disastrous. To remedy the problem deep infiltration must be reduced again, preferably by increasing plant water use and at the same time increasing agricultural production. In this paper details are presented of a study in western Victoria of the relative effects of conventional tilling and deep ripping on water movement under, and yield of, phalaris and lucerne pastures on a texture contrast soil. Deep ripping reduced water logging and thus increased lucerne survival. Deep ripping increased penetrability to roots. It appeared to increase yield of both lucerne and phalaris significantly, and thus their water use. Deep ripping appeared, however, to decrease run-off and increase lateral flow to preferential flow channels leading downward; thus deep ripping appears to also increase deep infiltration. In addition it was observed that on this particular texture contrast soil the first major throttle to downward flow of water is not at the top of the B horizon but near the top of the C horizon. This would have considerable ramifications in terms of soil management.

Herbage Intake Rates of Beef Cattle Grazing Alfalfa1

AbstractAlfalfa (Medicago sativa L.), a forage crop unique in that it has high potential in terms of both yield and quality, has considerable capacity for animal production when grazed under management that is based on its growth and development. Two grazing experiments, using balanced change‐over designs, were set up to measure the ingestive behavior of beef heifers (Bos taurus) during the first, second, and third hours of grazing sessions on alfalfa pastures established on Maury silt loam (fine, mixed, mesic Typic Paleudalfs). In Exp. I where the herbage mass, in terms of dry matter (DM), was 3.06 Mg ha−1 and the herbage DM allowance was 6.1 kg h−1 per heifer, animals ingested DM at 2.96, 1.88, and 1.56 kg h−1 during their first, second, and third hours of grazing, respectively. The mean rates of biting were 26, 21, and 19 bites min−1 for the same periods. Herbage DM intake per bite declined linearly from 1.96 to 1.54 to 1.36 g for each hour increment in grazing time. Forage utilization was 51, 32, and 27% for the same increments. In Exp. II where the herbage mass (DM) was 1.74 Mg ha−1 and the allowance was 3.4 kg h−1, heifers ingested 2.35, 1.47, and 1.20 kg h−1 during their first, second, and third hours of grazing, respectively. The mean rates of biting were 34, 22, and 18 bites min−1 during the same periods within the grazing session. Herbage DM intake per bite averaged 1.17 g and did not vary within the grazing session. Forage utilization was 75, 47, and 37% during the three consecutive hours within the grazing session. Maximum rates of herbage intake were characterized by larger bites and relatively slow rates of biting. Rates of herbage intake were considerably higher during the first hour of grazing than during the second and third hours. In a 3‐h grazing session, animals consumed 47, 29, and 24% of their intake during the first, second, and third hours, respectively.

Potential of medic and lucerne pastures in the rûens area of the Southern Cape

Abstract The potential of dryland lucerne and medic pastures was compared over a range of stocking rates, i.e. three, four, five, six, seven and eight merino ewes per hectare, in the Rûens area of the Southern Cape. It was found that the animal production potential of lucerne pastures was higher than that of medic pastures. This was attributed to the higher amount of available green pasture material during summer and the higher average legume content of the green material throughout the year on the lucerne pastures. Curvilinear relationships were apparent in most cases between production per animal and stocking rate on both pasture types.

Ruminal changes in monensin- and lasalocid-fed cattle grazing bloat-provocative alfalfa pasture.

Microbial and fermentation changes in the rumen in monensin- and lasalocid-fed cattle grazing bloat-provocative alfalfa pasture were studied using genetically bloat-susceptible, ruminally-cannulated adult cattle. Monensin at .66 and .99 mg/kg body weight daily reduced the severity of legume bloat by 41 and 73%, respectively. The same doses of lasalocid reduced bloat by 25 and 12%. Comparison of ruminal contents from animals before treatment with ruminal contents from antibiotic-treated animals showed no differences in pH, ammonia, soluble N, soluble carbohydrate, ethanol-precipitable slime and anaerobic bacterial counts. Monensin treatment decreased protozoal numbers and microbial activity, as evidenced by lower gas production from in vitro fermentation of ground alfalfa hay when compared to pretreatment. Lasalocid had no effect on protozoal counts and in vitro gas production. Addition of monensin or lasalocid (12 micrograms/ml) to in vitro fermentation of chopped, fresh alfalfa reduced microbial activity as evidenced by higher soluble N, lower ammonia concentration and decreased gas production. Monensin reduced the amount of ethanol-precipitable slime and protozoal numbers. Reduction in the severity of bloat when monensin was fed appears to be due to decreased protozoal numbers, which resulted in decreased gas production. Lasalocid did not reduce legume bloat because of its minimal effect on the ruminal protozoa.

Performance ofMedicago sativaunder dryland conditions on the eastern Highveld

Abstract Increased livestock numbers and improved animal performance based on dryland lucerne pastures requiring little or no nitrogenous fertilizer have been demonstrated to be feasible on the eastern Highveld. With large scale planting of lucerne‐based pasture (25% of arable land) 350 to 500% more sheep products can be delivered at a lower cost. When lucerne is included in crop rotations the production cost of grain can also be reduced. The increased usage of lucerne‐based pastures, especially for sheep and dairy enterprises, will also reduce the pressure on natural pasture and improve the conservation of vegetation, soil and water resources.

The growth of improved pastures on acid soils. 2. The effect of soil incorporation of lime and phosphorus on the growth of subterranean clover and lucerne pastures and on their response to topdressing

Subterranean clover responds poorly to superphosphate application on some acid soils of the Southern Tablelands of New South Wales. A field experiment was undertaken, for two years, to examine the effects of incorporating large additional amounts of superphosphate or rock phosphate in the soil, with and without lime, on the growth of subterranean clover, lucerne and phalaris sown with recommended rates of lime superphosphate. Dry matter responses of subterranean clover and lucerne to superphosphate topdressing in the second year were also recorded. In the first year, subterranean clover growth was increased by the additional lime and by lime plus superphosphate. Lucerne growth was increased by additional lime. In the second year, the growth of subterranean clover was increased by the lime treatments and the superphosphate treatments applied in the previous year and by the deep incorporation into the soil of lime and superphosphate together. Subterranean clover growth also responded to the application of rock phosphate without lime. Lucerne dry matter production in the second year was increased by the lime, superphosphate and rock phosphate treatments applied in the first year. Lime application increased the yield responses of subterranean clover and lucerne to superphosphate topdressed in the second year. Lime application had no effect on the nitrogen content of the clover but increased that of lucerne. Lime application reduced the aluminium levels in the tops of all three species. The data suggest that the responsiveness of pastures to superphosphate on these soils is increased by the application of lime and rock phosphate and is related to low nitrogen fixation and high aluminium levels in the plant.

Origin and assessment of water repellency of a sandy South Australian soil

The water repellency of a sandy lucerne pasture soil is critically dependent on aqueous extraction and subsequent drying procedures. Freeze-drying converts a very severely water-repellent soil into a readily wettable soil, but subsequent rewetting and oven-drying regenerates water repellency. These changes are ascribed to changes in the molecular conformation of the organic matter. Prolonged shaking detaches organic matter coatings from sand particles and so reduces repellency. Allowing for these effects, it is shown that a sequence of alcohol-benzene extraction, acid leaching, and NaOH extraction removes the major part of the water-repellent substances present.