Forage Mineral Research Articles

Technical note: Rapid mineral determination in forages by X-ray fluorescence

A large portion of the cow's ration is composed of forages that can vary greatly in mineral concentrations, which may affect animal performance and health. Current methods for mineral analysis require sample destruction either through wet or dry ashing and complex analytical techniques for individual minerals. Energy dispersive X-ray fluorescence (EDXRF) is a nondestructive, multi-mineral, spectroscopy technique, which makes mineral quantification simple, direct, and affordable. The study objective was to evaluate the prediction performance of EDXRF of Na, Mg, P, S, Cl, Ca, K, Mn, Fe, Cu, and Zn concentrations in forages. Twelve certified plant samples with a wide range in mineral concentrations were used to develop calibrations, and 35 forages (18 alfalfa hays, 10 grass hays, 7 corn silages) with measured mineral concentrations, which were collected over several years from 3 proficiency programs, were used as an independent validation set. All the samples were previously dried and finely ground and were prepared by compressing them into a round dense pellet, 40 mm in diameter, using a 40-ton pneumatic laboratory press. Samples were scanned using an EDXRF instrument enhanced for lighter minerals like Na and Mg. Samples were scanned at 20 keV and at 40 KeV associated with an Al filter, for a total analysis time of approximately 6 min. Calibrations were developed with Bruker SpectraEDX (Bruker, Hamburg, Germany) software and optimized to minimize the standard error of calibration. All of the minerals had acceptable calibration performance with coefficient of determination ranging from 0.93 (P) and 0.99 (Cl, Ca, and Mn) and coefficients of variation within 5 to 14%, which are similar to the coefficients of variation of the reference analysis. The coefficients of variation for Na was an exception, with a coefficients of variation of 29%. The validation set obtained similar statistical results as that observed in calibration. The root mean square error of prediction corrected for bias was similar to the standard error of calibration, indicating that it is possible to build a robust calibrations that performed well across different type of forages by using 12 reference samples with a sufficient range in mineral concentrations that were determined accurately. A bias correction was necessary to improve prediction accuracy only for K (-0.23% dry matter) and Ca (-0.16% dry matter). Energy dispersive X-ray fluorescence demonstrated the ability to be an accurate, direct, and simple technique for forage mineral analysis.

Mineral constraints on arctic caribou (Rangifer tarandus): a spatial and phenological perspective

AbstractArctic caribou (Rangifer tarandus) have the longest terrestrial migration of any ungulate but little is known about the spatial and seasonal variation of minerals in summer forages and the potential impacts of mineral nutrition on the foraging behavior and nutritional condition of arctic caribou. We investigated the phenology, availability, and mechanistic relationships of calcium, phosphorus, magnesium, sodium, potassium, iron, manganese, copper, and zinc in three species of woody browse, three species of graminoids, and one forb preferred by caribou over two transects bisecting the ranges of the Central Arctic (CAH) and Western Arctic (WAH) caribou herds in Alaska. Transects traversed three ecoregions (Coastal Plain, Arctic Foothills and Brooks Range) along known migration paths in the summer ranges of both herds. Concentrations of mineral in forages were compared to estimated dietary requirements of lactating female caribou. Spatial distribution of the abundance of minerals in caribou forage was associated with interactions of soil pH and mineral content, while temporal variation was related to plant maturity, and thus nitrogen and fiber content of forages. Concentrations of sodium were below caribou requirements in all forage species for most of the summer and adequate only on the Coastal Plain during the second half of summer. Phosphorus declined in plants from emergence to senescence and was below requirements in all forages by mid‐summer, while concentrations of copper declined to marginal concentrations at plant senescence. Interactions of sodium with potassium, calcium with phosphorus, and copper with zinc in forages likely exacerbate the constraints of low concentrations sodium, phosphorus, and copper. Forages on the WAH contained significantly more phosphorus and copper than forages collected on the CAH transect. We suspect that migrations of caribou to the Arctic Coastal Plain may allow parturient females to replenish sodium stores depleted by foraging inland through the long arctic winters, while also extending the availability of adequate phosphorus, if animals are able to selectively track emerging waves of forage.

Urochloa decumbens grown with different Eucalyptus clones in an integrated crop-livestock-forest system

The objective of this study is to evaluate the forage mass, chemical composition, mineral content, and mineral absorption in signal grass (Urochloa decumbens) grown with different eucalypt clones in an integrated crop-livestock-forest (iCLF) system. The split-split-plot scheme included three replicates arranged in a completely randomized block design. The eucalyptus clones GG 100 and I 144 (Eucalyptus grandis × Eucalyptus urophylla) and VM 58 (Eucalyptus grandis × Eucalyptus camaldulensis) were distributed in the plots. The split plots corresponded to the growth ages of signal grass (10, 17, 24, 31, 38, 45, and 52 days after corn harvest for silage). The split-split plots corresponded to two sampling sites: center of the inter-row and soil under the Eucalyptus canopy. The Eucalyptus clones did not affect the forage mass of the grass. Forage mass was increased linearly as the grass matured and was more readily available in the center of the inter-row than under the tree canopy. The grass grown with clone I 144 presented better chemical composition, with higher levels of crude protein and phosphorus and lower levels of neutral detergent fiber. The Eucalyptus clones did not significantly affect mineral absorption. However, the Eucalyptus clones, grass age, and sampling sites significantly changed potassium absorption. It is concluded that the forage mass of signal grass is suitable for use in grazing at 38 to 52 days after corn harvest in the iCLF system in the autumn season in the Midwest region of Minas Gerais, without compromising the chemical composition of the grass.

Macro-mineral concentrations in soil and forage in three grassland sites at Zacatecas

Mineral concentration in forage is an important factor for extensive livestock production. Therefore, a study was performed in order to evaluate the soil mineral contents and their relationships with forage mineral concentrations taking into account three grassland sites located at Zacatecas state, México. Soil organic matter (OM) content and pH as well as soil and forage contents of Ca, P, Mg, Na and K were estimated. Soil OM contents were not different (P>0.05) among sites averaging 2.99 %. Soil pH of site 2 was higher (P£0.05) than those of sites 1 and 3. Soil of site 2 had higher P, Ca and Mg concentrations than the minimum contents used as references. Soil contents of Na and K were lower than the reference contents suggesting deficiencies in all three sites. Considering requirements for growing cattle, P, Ca and Na were at insufficient levels in forage from all three sites. Significant correlations (r Pearson) suggest a positive effect of soil P content on forage P and Mg concentrations. Soil P content could affect forage Ca concentration and Ca:P ratio. Other correlations suggest soil Ca negative effects on forage Ca concentration and Ca:P ratio.

Hematological and Mineral Profiles of Reproductive Failure of Exotic Breed Cattle in Payakumbuh, West Sumatra, Indonesia.

Female exotic breed cattle raised by traditional small farms are susceptible to reproductive disturbances that result in failure or delay to produce calves. The present research investigated the hematologic profiles of exotic breed cattle having reproductive troubles versus heifers and pregnant cows raised by small farms. A survey was conducted to identify the reproduction performance of 160 female Simmental cows raised at 15 smallholders in Payakumbuh, West Sumatra, Indonesia. Samples of blood were collected from 15 female Simmentals comprised of three different reproductive statues (heifers, pregnant and reproductive failure, n = 5 animals each). Blood plasma was then separated and analyzed for hematological parameters [hemoglobin (Hb), hematocrit, red and white blood cell, mean corpuscular Hb concentration], total protein and mineral content (Ca, P, Mg, Fe, Mn, Cu and Zn). Samples of fodder feed were collected from 15 farms for determination of dominant species and mineral composition. Data were statistically analyzed in a completely randomized 3×5 design for blood parameters and 4×3 design for forage minerals. About one-third of female cows found to have reproductive problems. Anestrus was found to be the most important causal factor for reproductive failure, followed by postpartum infertility (poor fertilization). The reproductive failure group had significantly lower (p<0.05) Hb levels, hematocrit, red and white blood cell and protein but higher mean corpuscular Hb concentration. Considering the critical levels in the blood and feed, the animals were deficient in protein, Ca, P, Mn and Cu. Anestrus and repeated insemination were found to be the major causes of reproductive disorders in exotic breed cattle under small farm conditions that results in delay or failure to produce calves. Reproductive disturbances in Simmental cows were most likely associated with nutrient deficiencies.

Effect of source of trace minerals in either forage- or by-product–based diets fed to dairy cows: 2. Apparent absorption and retention of minerals

Eighteen multiparous cows were used in a split-plot replicated Latin square with two 28-d periods to evaluate the effects of source of supplemental Cu, Zn, and Mn (sulfates or hydroxy) on apparent absorption of minerals when fed in either a forage- or by-product-based diet. The by-product diets were formulated to have greater concentrations of NDF and lesser concentrations of starch, and specific ingredients were chosen because they were good sources of soluble fiber and β-glucans, which bind trace minerals in nonruminants. We hypothesized that hydroxy trace minerals would interact less with digesta and have greater apparent absorption compared with sulfate minerals, and the difference in apparent absorption would be greater for the by-product diet compared with the forage-based diet. During the 56-d experiment, cows remained on the same fiber treatment but source of supplemental trace mineral was different for each 28-d period; thus, all cows were exposed to both mineral treatments. During each period cows were fed no supplemental Cu, Zn, or Mn for 16 d, followed by 12 d of feeding supplemental minerals from either sulfate or hydroxy sources. Supplemental minerals for each of the mineral sources fed provided approximately 10, 35, and 32 mg/kg of supplemental Cu, Zn, and Mn, respectively, for both fiber treatments. Total Cu, Zn, and Mn dietary concentrations, respectively, were approximately 19, 65, and 70 mg/kg for the forage diets and 21, 85, and 79 for the by-product diets. Treatment had no effect on dry matter intake (24.2 kg/d) or milk production (34.9 kg/d). Cows consuming the by-product diets had greater Zn (1,863 vs. 1,453 mg/d) and Mn (1,790 vs. 1,588 mg/d) intake compared with cows fed forage diets, but apparent Zn absorption was similar between treatments. Manganese apparent absorption was greater for the by-product diets compared with the forage diets (16 vs. 11%). A fiber by mineral interaction was observed for Cu apparent absorption, as cows fed hydroxy minerals with forage diets had greater apparent absorption compared with cows fed sulfate minerals; however, the opposite was observed with the by-product diets. Source of supplemental trace minerals and type of fiber in diets affected availability of Cu and Mn and should be considered in ration formulation.

Effect of source of trace minerals in either forage- or by-product–based diets fed to dairy cows: 1. Production and macronutrient digestibility

Excess rumen-soluble Cu and Zn can alter rumen microbial populations and reduce fiber digestibility. Because of differences in particle size and chemical composition, ruminal and total-tract digestibility of fiber from forage- and by-product-based diets can differ. We hypothesized that, because of differences in mineral solubility, diets with hydroxy rather than sulfate trace minerals would have greater fiber digestibility, but the effect may depend on source of fiber. Eighteen multiparous cows were used in a split-plot replicated Latin square with two 28-d periods to evaluate the effects of Cu, Zn, and Mn source (sulfates or hydroxy; Micronutrients USA LLC, Indianapolis, IN) and neutral detergent fiber (NDF) source (forage diet = 26% NDF vs. by-product = 36%) on total-tract nutrient digestibility. During the entire experiment (56 d) cows remained on the same fiber treatment, but source of supplemental trace mineral was different for each 28-d period so that all cows were exposed to both mineral treatments. During each of the two 28-d periods, cows were fed no supplemental Cu, Zn, or Mn for 16 d followed by 12 d of feeding supplemental Cu, Zn, and Mn from either sulfates or hydroxy sources. Supplemental minerals for each of the mineral sources fed provided approximately 10, 35, and 32 mg/kg of supplemental Cu, Zn, and Mn, respectively, for both fiber treatments. Total dietary concentrations of Cu, Zn, and Mn were approximately 19, 65, and 70 mg/kg for the forage diets and 21, 85, and 79 mg/kg for the by-product diets, respectively. Treatment had no effect on dry matter intake (24.2 kg/d) or milk production (34.9 kg/d). Milk fatty acid profiles were altered by fiber source, mineral source, and their interaction. Cows fed the by-product diets had lower dry matter (65.9 vs. 70.2%), organic matter (67.4 vs. 71.7%), and crude protein digestibility (58.8 vs. 62.1%) but greater starch (97.5 vs. 96.3%) and NDF digestibility (50.5 vs. 44.4%) compared with cows fed the forage treatment. Feeding increased concentrations of by-products decreased total digestible nutrients regardless of mineral source. Feeding hydroxy Cu, Zn, and Mn increased NDF digestibility (48.5 vs. 46.4%) but had no effect on total digestible nutrients.

BILL E. KUNKLE INTERDISCIPLINARY BEEF SYMPOSIUM: Assessing the mineral supplementation needs in pasture-based beef operations in the Southeastern United States.

Macro- and microminerals are required for all physiological processes in beef cattle. When mineral deficiencies occur in pasture-based production systems, a multitude of deficiency symptoms may occur, and most often, these deficiencies result in hidden losses to include reduced production potential, reduced immunity, and reproductive failure. More severe deficiencies will result in specific deficiency symptoms, depending on the specific mineral deficiency. In pasture-based beef operations, specific deficiency symptoms are seldom observed. Forage mineral supply is highly variable and dependent on the forage type, stage of forage growth, and soil fertility. Grazing cattle mineral requirements change throughout the production cycle. With the variability of forage mineral supply and the changing mineral requirements, care must be taken when developing mineral supplementation programs for grazing cattle. The macrominerals function in nerve transmission, bone development, and metabolism and as electrolytes. These are Ca, P, Mg, Na, K, Cl, and S. The microminerals function in various areas of metabolism, immune responsiveness, reproductive efficiency, and many other functions. These minerals are Zn, Cu, Fe, I, Mn, Se, Mo, and Co. Of these macro- and microminerals, those that are important for supplementation to pasture-based cattle include Ca, P, Mg, Na, Cl, Zn, Cu, I, Mn, Se, and Co. However, the amounts to be supplemented will depend on the specific mineral requirements and the forage supply of the minerals. Consequently, the development of free-choice mineral supplementation programs is a moving target. Generally, this entangled mess is sorted by taking one mineral at a time into consideration. However, in doing so, one has to be cognizant of the many interactions that occur when changing intake of just 1 mineral in the supplement with respect to the amount supplied in the base forage. Often times, mineral nutrition problems of one or more minerals are created when trying to correct a deficiency of another mineral. This paper will address specific factors that are important to consider when developing and delivering mineral supplementation programs in pasture-based production systems in the Southeastern United States.

Effect of some minerals in soil and forage on same minerals in cattle plasma at three sites in the province of Thi-Qar

The objective of this investigation is to evaluate the level of the some minerals (sodium, potassium and calcium) in the soil, forage and Cattle plasma, the specimens taken from three districts (Nasriya, Shatra and Sookalshukh) in Thi-qar province. Results showed an increase in the concentration of sodium element in soils Nasiriya, potassium, calcium element in soils Sookalshukh region compared to other regions, while plants Sookalshukh region showed the highest concentration of sodium and calcium either the Nasiriya area showed the highest concentration of potassium compared to other regions. The results show that significant (p≤0.05) increase in the cattle plasma sodium concentration in Nasriya region compared with the Shatra and Sookalshukh , significant (p≤0.05) increase in Cattle plasma potassium concentration in Nasriya district compared with Shatra and Sookalshukh but there is significance (p≤0.05) change found in Cattle plasma calcium in shatra compared with the two studied areas. There was a highly significant between grass and animal sodium and potassium element, soil and grass and animals of the calcium element.

Mineral Status and Interrelationship in Soil, Forage, and Blood Serum of Horses in the Rainy and Dry Seasons

The objective was to evaluate the content of P, Ca, Mg, K, Na, Cu, Fe, Zn, Se, and Mn in soil, forage, and serum of horses in several production units (PU) during rainy and dry seasons and predict their concentration in serum from their content in soil and forage. Soil and pastures were sampled in the dry (November–December) and in rainy seasons (June–July), and blood samples were collected from the jugular vein of 76 horses in both seasons at four PU. The experimental design was a completely random design within a 4 × 2 (PU × season) factorial arrangement of treatments. Concentration of minerals in soil differed (P < .05) among PU, and contents of P, Ca, Mg, and K were low; Zn and Fe were high; and Cu and Mn were adequate. Mineral concentrations in forage differed among PU and season, and among PU within season (interaction P < .05). Contents of Ca, Mg, Na, Zn, and Cu were low; Fe was high; and P, K, Se, and Mn adequate. The mineral concentration in equine blood serum differed (P < .05) among PU and season. Overall, there were deficiencies of P, Ca, Mg, Na, Cu, and Se, but adequate amounts of K, Zn, and Fe. There are imbalances of minerals in soil and forages which effected their concentration inequine blood.

0227 Relationship between forage quality parameters and mineral intake in grazing beef cattle

0227 Relationship between forage quality parameters and mineral intake in grazing beef cattle

Mineral Concentration and Standing Crop Yield Dynamics of Forages in Semi-arid Communal Grazing Lands of South Africa: Effect of Landscape and Season

Semi-arid African rangelands are characterized by heterogeneous topography and distribution of grazing forages. In these ecosystems, grasses are the main sources of livestock feed with few species contributing to the bulk of the nutrient intake. Forage yield and elements availability play a significant role in determining the adequacy of nutrients intake and fodder flow plan, but limited information is available on their dynamics for the semi-arid South African communal rangelands. There is also little data on factors influencing concentrations of forage minerals throughout the year. We investigated the standing crop yield (DM) and element concentrations of major forages and evaluated their spatial and temporal variations. We conducted the study in two semi-arid (Highland and Lowland) communal rangelands in the Eastern Cape province, South Africa. Herbages for major forage species were harvested from three landscape positions (upland, slopping and bottomland) over four seasons (summer, autumn, winter and spring) in 2012/2013 to determine DM, macro and micro element concentrations. Our results confirm great variations in DM and mineral contents between grass species, across landscapes and seasons. Compared to the Lowland, more elements in the Highland showed interaction effects between species, landscape or seasons. While species variations are attributed mainly to biotic and anthropogenic factors, spatial and temporal variations may be due to topographic, edaphic and/or climatic variations. Minerals most likely to be found deficient were P, Mg, Zn, Cu and K, but this depends on seasons and landscapes. Their amendments through supplementation may deserve utmost consideration.

Effect of Intercropping Between Corn (Zea mays) and Peanut (Arachis hypogaea) with Arbuscular Mycorrhizal (AMF) on the Yield and Forage Mineral Content

Effect of Intercropping Between Corn (Zea mays) and Peanut (Arachis hypogaea) with Arbuscular Mycorrhizal (AMF) on the Yield and Forage Mineral Content

Manganese and Magnesium Status of Forage Grasses, and It’s Implications for Grazing Animals, Dareta Village, Zamfara, Nigeria

Forage mineral concentration is of considerable importance to livestock production. High concentrations of lead in the soil environment causes imbalance of mineral nutrients in growing plants. In most cases lead blocks the entry of cations (potassium, Calcium, Magnesium, Manganese, Zinc, Copper, and iron) and anions (NO3) in the root system. The elevated levels of lead in soil and pastures reported in Zamfara, following mass acute lead poisoning crisis in the Northern Nigerian state informed this study. The forage concentrations of Manganese and Magnesium were investigated with respect to the nutrient requirement of the grazing ruminants in Dareta village. The analysis was carried out using Atomic Absorption Spectrophotometer (AAS) while method validation was achieved using reference material, Lichen (IAEA-336). Based on the data recorded, it was concluded that the concentration of these two minerals varied among different Original Research Article International Research Journal of Pure & Applied Chemistry, 4(2): 203-212, 2014 204 pastures. The difference was statistically significant at 95% confidence level. Manganese concentration in the forage ranged from 2.89mg/kg to 137.00mg/kg dry weight in different pastures and Magnesium from 22.84mg/kg to 62.59mg /kg dry weight. The concentration of Manganese and Magnesium determined in this study are significantly lower than their recommended minimum concentrations (critical levels) in pasture for grazing animals. The implications of these findings for grazing animals are fully discussed.

Long‐Term Manure Applications Impact on Irrigated Barley Forage Mineral Concentrations

Agronomy Journal 105:1441–1450 (2013). doi:10.2134/agronj2012.0204 In the above article the authors have discovered errors in the title for Table 3 and captions for Fig. 1 and Fig. 2. The unit for the manure application rates should be Mg ha–1 yr–1, not kg ha–1 yr–1. In addition, the fertilizer application unit should be kg N ha–1 instead of kg ha–1. The units are correct everywhere else in the manuscript and these errors do not change the results and discussion. The correct title for Table 3 and captions for Fig. 1 and Fig. 2 are shown below. We apologize for the error in the publication. Table 3. Properties of the surface soil (0–15-cm depth) under the treatments investigated, including a check (CK); 100 kg N ha–1 NH4NO3 (FER); manure applied at rates of 60, 120, and 180 Mg ha–1 yr–1 (wet basis) for 37 continuous yr (M60, M120, and M180, respectively); and manure applied at rates of 60, 120, and 180 Mg ha–1 yr–1 for 30 continuous yr followed by 7 yr discontinued applications (D60, D120, and D180, respectively). Fig. 1. Soil inorganic N (NO3–N + NH3–N) concentrations in (A) 2003 and (B) 2008 under the treatments investigated, including a check (CK), 100 kg N ha–1 NH4NO3 (FER); manure applied at rates of 60, 120, and 180 Mg ha–1 yr–1 (wet basis) for 37 continuous yr (M60, M120, and M180, respectively), and manure applied at rates of 60, 120, and 180 Mg ha–1 yr–1 for 30 continuous yr followed by 7 yr after manure applications had been discontinued (D60, D120, and D180, respectively). Horizontal bars indicate the standard error. Bars with different letters for each depth and each year indicate a significant difference (P < 0.05, Bonferroni test). Fig. 2. Annual N and P recovery [removal from plant uptake, kg ha–1/(input + previous year balance, kg ha–1) from manure applications × 100] from 1974 to 2010 under the treatments investigated, including a check (CK), 100 kg N ha–1 NH4NO3 (FER); manure applied at rates of 60, 120, and 180 Mg ha–1 yr–1 (wet basis) for 37 continuous yr (M60, M120, and M180, respectively), and manure applied at rates of 60, 120, and 180 Mg ha–1 yr–1 for 30 continuous yr followed by 7 yr after manure applications had been discontinued (D60, D120, and D180, respectively).

Long‐Term Manure Applications Impact on Irrigated Barley Forage Mineral Concentrations

Long‐term manure use near livestock feedlot operations can result in soil nutrient imbalances. We investigated the impact of continuous (37‐yr) and discontinued (30‐yr continuous + 7 yr without applications) manure applications on soil properties and barley (Hordeum vulgare L.) yield and nutritive value under semiarid field conditions in southern Alberta, Canada. Feedlot cattle manure annual applications were 0, 60, 120, and 180 Mg ha–1 (wet weight) to an irrigated Chernozemic soil. After 37 yr, barley yields were not affected by manure applications, while forage crude protein (CP), NO3–N, P, K, and Zn concentrations increased (P &lt; 0.01). Forage Ca/P ratios decreased and K/(Ca + Mg) ratios increased with manure applications to critical levels of illness potential in ruminants. Discontinuing manure applications did not affect forage CP content; however, forage P and K concentrations declined (P &lt; 0.01) with decreases in soil P and K. This resulted in the return of forage Ca/P ratios within the recommended levels. Seven years after manure applications were discontinued, forage Zn concentrations were similar to concentrations from unmanured plots. Although forage nutrient balances for animal nutrition improved after manure applications were discontinued, soil nutrient recovery was small, and soil P, K, and Zn concentrations in the discontinued plots remained greater (P &lt; 0.01) than concentrations in the unmanured plots and well above those required for optimum crop growth.

Approximation of some minerals in soil and forage as a function of non-conventional compost: A case study

In present study concentration of some metals (Magnesium, Nickel and Calcium) were determined in soil and different parts of Avena sativa treated with poultry waste grown in the pots. Nine different treatments of poultry waste were used: 0 (control), 60, 90, 120 and 150 kg/ha applied to soil as full doses before sowing, and 60, 90, 120, and 150 applied as two equal splits, 1st before sowing and the 2nd before flower instigation. The samples of soil were obtained after mixing the poultry waste with soil in each pot before sowing. Different parts (roots, leaves, and seeds) of plants were taken after 90 days of sowing and after grain filling. Samples of soil and forages were analyzed. Mg concentrations found both in soil and plants were non-significantly affected by treatments and were lower than the requirements of ruminants in forage crops, but above requirement of forages in soil. Soil and forage Ni was affected non-significantly from the treatments of poultry waste and soil and forage Ni levels were found to be lower than the toxic level for animals and forages. Soil Ca was affected non-significantly by treatments having far lower values than the requirements of both forage species and ruminants. The study showed that soil Mg was higher and Ca was lower than the requirements of forages, but forage Mg and Ca were not fulfilling the requirements of livestock indicating the non significant effect of poultry waste on their concentrations. From the results of this study it has been anticipated that various deficiency problems in livestock may be resulted as these elements play very important role in animals’ metabolic progression. Therefore, soil amendment with poultry manure along with other synthetic fertilizers for enhancing the levels of various minerals is acceptable. The soil amendment and specifically tailored mineral mixture with appropriate proportion of these elements is the dire needs for livestock consuming Avena sativa in pasture treated with poultry waste.

Contenido mineral de forrajes en predios de ovinocultores del estado de Yucatán

The purpose of the present study was to diagnose contents of five minerals in forages that grow in sheep farms during the rainy season in the State of Yucatan, Mexico. A total of 50 farms in 47 municipalities were sampled and 88 forage samples were gathered. Ca, K, Fe, Cu and Zn contents were determined through atomic absorption spectrophotometry and average content and dispersion parameters were estimated. Results were analyzed using a General Linear Model to detect effects of sampling area (Center, East, South, West), soil type (Rendzina, Litosol, Luvisol, Vertisol, Cambisol), forage type, interactions and experimental error. Average results obtained were 0.53±0.41 % Ca, 0.51±0.24 % K, 12.8±10.1 % Cu, 251±149 ppm Fe and 27.6±12.6 ppm Zn. Nutrient content adequacy for 40 kg single lamb lactating ewes was 34, 48, 27.8 and 57.7 % for Ca, K, Cu and Zn, respectively. Practically no deficiencies were found for Fe. Both Ca and Zn content was greater (P<0.05) in East and West areas. Soil type effect was only found in Cambisols, which showed a greater Cu content (P<0.05). Rangeland forage showed the higher Ca, K, Cu and Zn content (P<0.05). It can be concluded that nutrient inadequacies were found for Ca, K, Cu and Zn, while Fe showed high levels. Formulation and manufacture of mineral supplements meant for sheep in Yucatan should include these minerals and be Fe free.

Forage Mineral Concentrations in Grazed, Warm-Season Bahiagrass Pastures in Florida

AN243, a 4-page fact sheet by Bob Myer, Lee McDowell, Cheryl Mackowiak, and Ann Blount, discusses the concentrations of forage minerals in bahiagrass pastures for beef cattle, to determine adequate mineral levels and use of mineral supplements. Includes references. Published by the UF Department of Animal Science, July 2010.

Forage Mineral Concentrations and Mineral Status of Beef Cattle Grazing Cool Season Pastures in Northwestern Florida, Emphasizing Magnesium

A 68‐day study was conducted in North Florida to evaluate forage and beef cattle serum, liver, and urine mineral concentrations, emphasizing magnesium (Mg). Forty‐two Angus, Brangus, and Romosinuano cows in early lactation were divided into two groups and placed on ryegrass or oat pasture. Samples were collected every 2 weeks except for liver biopsies, which were collected only on day 68. Mineral concentrations were determined for forage, plasma, urine, and liver samples. All forage mineral concentrations except Mg, calcium (Ca), copper (Cu), cobalt (Co), selenium (Se), and zinc (Zn) were greater than critical levels for a beef cow in lactation. Forage Mg and Cu were severely deficient in both oats and ryegrass. All blood plasma mineral levels were greater than critical levels, but plasma Mg was borderline to slightly deficient. There should be special attention given to Mg supplementation because forages are deficient and contain excess potassium (K).