A Study on Seasonal Variability of Trace Elemental Status of Forages for Grazing Ruminants

An investigation was conducted to determine the trace- mineral concentrations of forages in relation to requirements of ruminants grazing in natural pastures in the province of Punjab, Pakistan during two different seasons. Animals were closely followed during grazing and forages corresponding to those consumed by the animals were taken and analyzed for copper (Cu), iron (Fe), zinc (Zn), manganese (Mn), and cobalt (Co) concentrations. The data on the trace- mineral concentrations showed that most of these minerals varied greatly as a function of seasons and sampling periods. The forage Cu, Fe, and Zn concentrations were affected by seasonal changes but no influence of season was observed on the concentrations of forage Mn and Co concentration. Forage Zn and Co, during both seasons and at some sampling intervals, and forage Mn during summer were at marginal deficient levels, and in contrast, all other forage trace-minerals were within the required range for ruminants during both seasons. Based on these results, the supplementation of Zn, Co, and Mn would seem most important to support optimum livestock productivity.     

Monthly variation of forage and soil minerals in central Florida II. trace minerals

Abstract

A two‐year study was conducted to determine the trace mineral status of cattle grazing forages (bahiagrass) and soils on a ranch in central Florida. Forage and soil samples were collected every month for two years. Month effect (P < 0.05) on soil trace mineral concentrations were observed in manganese (Mn) and zinc (Zn) in years 1 and 2, and in copper (Cu) and iron (Fe) only in year 2. All soil trace minerals studied showed higher (P < 0.05) concentrations in year 2. Month differences (P < 0.05) in forage trace mineral concentrations were found in cobalt (Co), Cu, Fe, Mn, molybdenum (Mo), selenium (Se), and Zn. The majority of forage trace minerals were higher in spring‐summer months. Year means were similar (P > 0.05) in forage trace mineral concentrations. Few and low correlation coefficients were observed between and within soil and forage trace minerals concentrations. Percentages of total forage collected with trace minerals below critical values (in parentheses) and suggestive of deficiency were as follows: in forage, Co (0.1 ppm), 93%; Cu (8 ppm), 98%; Fe (50 ppm), 75%; Mn (40 ppm), 41%; Mo (> 6 ppm), 0%; Se (0.2 ppm), 98%; and Zn (25 ppm), 84%; in soil, Cu (0.3 ppm), 77%; Fe (2.5 ppm), 7%; Mn (5 ppm), 91%; and Zn (1.5 ppm), 53%.     

Variation of forage and extractable soil minerals over two grazing seasons in North Florida

Abstract

A two‐year experiment was conducted at a north Florida farm to evaluate the mineral status of bahiagrass forages and soils. Forage samples were collected every 28 d throughout the grazing season, and soils evaluated twice yearly. The minerals calcium (Ca), sodium (Na), copper (Cu), cobalt (Co), selenium (Se), and zinc (Zn) were uniformly below the dietary requirements for growing beef cattle in both years. Forage magnesium (Mg), phosphorus (P), potassium (K), crude protein (CP), and manganese (Mn) were generally adequate throughout the grazing season, with the exception of low P concentration at the end of the growing season for both years. Extractable soil concentrations of Ca, P, K, Mg and Zn were adequate but low in Cu. Although CP was adequate (>7.0%) throughout the grazing season, IVOMD values were relatively low. There was a general trend for forage P, K, and IVOMD to decrease (P<0.05) with time.     

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).     

Effects of pasture‐applied biosolids on forage and soil concentrations over a grazing season in north Florida. II. microminerals

Abstract

The experiment rationale was to determine forage micromineral concentrations as effected by biosolids fertilization. We determined the effects of two exceptional quality biosolids on bahiagrass trace mineral concentrations as related to beef cattle requirements. Twenty‐five 0.8‐ha pastures were divided into five blocks. Two biosolids were applied as normal and double agronomic rates. The control received NH₄NO₃. Forages were analyzed for total copper (Cu), iron (Fe), manganese (Mn), zinc (Zn), molybdenum (Mo), cobalt (Co), and selenium (Se), and soils were analyzed for Mehlich I extractable Cu, Mn, and Zn. Some significant increases (P<0.05) in forage Co, Cu, Fe, Zn, and Se were observed at various sampling times, but the increases were generally small and biologically insignificant. Although forage Mo samples from pastures with the Tampa biosolids applied were consistently higher than the control (P<0.05), at no time did they approach levels considered toxic. Similar results were seen in forage Mn concentrations, with treatment Baltimore‐2X elevating (P<0.05) Mn concentrations as well. Deficiencies of Co, Cu, Zn, and Se are common in this Florida region and slight elevations due to biosolids treatment could be beneficial. Biosolids applied at the highest rates improved soil Cu and Zn concentrations above control soils and soil Mn was increased over the control at both sampling times for Baltimore‐2X. In relation to beef cattle requirements, the majority of forages were deficient in Co, Cu, Se, and Zn. In summary, biosolids fertilization slightly improved the micromineral status of forage and soil, without creating toxicity.     

Mineral concentrations of forages grazed by small ruminants in the wet season in benue state,Nigeria. II. Trace minerals and forage crude protein

Abstract

A total of 71 forage samples were analyzed for trace mineral and crude protein concentrations in three Agricultural zones of Benue State, Nigeria. The zones consisted of the Northern, Eastern, and Central zones, each of which was made up of four Local Government Areas. In each Local Government Area, grazing animals were followed and forages corresponding to those consumed were collected during the peak of the wet season (June) and analyzed for the nutrient composition. Deficiencies were observed in copper (Cu) and cobalt (Co) concentrations in all classes of forage, and in forage Cu and zinc (Zn) in all Local Government Areas in the Northern zone. A higher (P<0.05) forage Cu concentration was observed in legumes compared to other classes of forage in the Eastern zone. Concentrations of iron (Fe) and manganese (Mn) were considered adequate and their contents were not affected (P>0.05) by class of forage or Local Government Areas. In the Eastern zone, the contents of selenium (Se) in grass and tree leaf hay were higher compared to leguminous forage, which in turn was higher compared to Se concentrations in crop wastes. Only about 18% of total forage samples showed protein concentrations below the critical value of 7%. Supplementation of Cu, Zn, and Co would seem to be necessary in the Northern zone, and to a lesser extent in the Eastern zone for optimum productivity of grazing animals.     

In Vitro digestibility,crude protein content,and mineral concentrations of cynodon,brachiarin, and digitaria accessions in a humid tropical region of Puerto Rico

Abstract

The in vitro organic matter digestibility (IVOMD), crude protein (CP) content, and mineral composition of 11 grasses were compared between seasons in Puerto Rico and evaluated in relation to grazing ruminant requirements. Digitaria eriantha was the highest in IVOMD for both seasons, being higher (P<0.05) than 6 of 10 forages in the long‐day season and 4 of 10 in the shortday season. No differences (P>0.05) in CP content were observed among accessions at both seasons. Mean macroelement content of the accessions was generally adequate in relation to grazing ruminant requirements with the exception of sodium (Na) and magnesium (Mg). Forage microelement concentrations of cobalt (Co), copper (Cu), and zinc (Zn) were generally under the grazing ruminant requirements for the accessions evaluated during both seasons. Iron (Fe) and manganese (Mn) content were high in relation to requirements, especially during the short‐day season. Molybdenum (Mo) was not in excess for the accessions evaluated. The Zn concentrations were similar to the results reported from other experiments with higher fertilization levels. The selenium (Se) concentrations presented an apparent seasonal variation higher in the short‐day season, which is similar to other experiments with high fertilization levels.     

Mineral concentrations in leaves and stems of various forages of the Colombian paramo

Abstract

A study was conducted to determine the elemental composition of two plant fractions (leaves and stems) of several forage species in three sheep farms of the paramo in Colombia. The elemental composition of the forage species, and the relationship between soil chemistry and the elemental composition of the forages were also determined. Sampling periods corresponded to the end of the rainy season (May‐June 1987), and the middle end of the dry season (February 1988). Leaves were higher (P<0.05) than stems in the following: calcium, phosphorus, magnesium, potassium, iron, molybdenum, crude protein, and IVOMD. Overall percentage of deficiencies were related to the requirements for sheep as follows: calcium (88%, 13%), phosphorus (50%, 27%), magnesium (85%, 41%), potassium (13%,3%), sodium (94%, 96%), iron (10%, 4%), copper (82%, 65%), manganese (7%, 0%), zinc (46%, 42%), cobalt (92%, 85%), selenium (77%, 65%), crude protein (45%, 8%) for stems and leaves, respectively.

Based on analyses, elemental, crude protein and IVOMD concentrations of forage species, tended to differ. Soil‐forage correlation coefficients of the same mineral for the rainy season were calcium (r = 0.81), magnesium (r = 0.89), potassium (r = 0.71), zinc (r = 0. 69). For the dry season, correlations were calcium (r = 0.61) and magnesium ( r = 0.58). Results indicated low correlation coefficients between most soil and forage elements, and that they are not of great value in assessing the elemental status of grazing sheep in the paramo.     

Yield,in vitro digestibility,crude protein,and mineral concentration of eight Digitaria introductions in Puerto rico

Abstract

Dry matter (DM) yield, in vitro organic matter digestibility (IVOMD), crude protein (CP) and mineral composition of eight Digitaria accessions were compared between long‐ and short‐day seasons in the semiarid southern region of Puerto Rico and evaluated in relation to grazing ruminant requirements. Digitaria milanjiana 6416 was consistently among the highest DM yielding accessions in both seasons. The mean IVOMD was similar in both seasons for most accessions. Concentrations of CP, magnesium (Mg), copper (Cu), zinc (Zn), cobalt (Co), and selenium (Se) were below the recommended levels for grazing ruminants in both seasons. This study suggests the need for livestock mineral supplementation, even under conditions of high pasture fertilization (NPK) and forage‐growing conditions in the semiarid southern region of Puerto Rico.     

Mineral Concentrations of Cool Season Pasture Forages in North Florida During the Winter-Spring Grazing Season: II. Trace Minerals

Trace mineral concentrations of annual cool season pasture forages grazed by growing beef cattle during late fall-winter-spring grazing season were evaluated during two experimental cool season grazing studies, each lasting two years at the North Florida Research and Education Center (NFREC), Marianna, Florida. Eight 1.32 ha fenced pastures or paddocks were divided into two groups of pasture land preparation/planting methods, four pastures for the sod seeding treatments (SS) and four for the prepared seedbed treatments (PS). Two different pasture forages, small grains, (rye/oats mix) with or without ryegrass for the first two years (Study 1); and oats with ryegrass or ryegrass only for the last two years (Study 2) were planted in these pasture lands. Each of the four forage, type, and cultivation combination treatments was assigned to two pastures each year, thereby giving two replicates per pasture treatment per year. Forage samples were collected at the start of pasture grazing and twice monthly thereafter until the end of grazing season, pooled by month, and analyzed for copper (Cu), iron (Fe), zinc (Zn), manganese (Mn), cobalt (Co), molybdenum (Mo), and selenium (Se). Liver biopsies and blood plasma samples were collected from the tester cattle only during the spring of year two of Study 2. Liver was analyzed for Cu, Fe, Mn, Co, Mo, and Se and plasma for Cu, Fe, Zn, and Se. Forage trace mineral concentrations were found to differ by month in Cu (P < 0.01), Fe and Zn (P < 0.0001) in both studies, and with Mn (P < 0.0001) in Study 2 only. Pasture forage type effects on Cu (P < 0.05), Fe and Zn (P < 0.01), and Se (P < 0.05) and forage type by month interactions on Cu and Mn (P < 0.0001), and Zn (P < 0.05) were observed in Study 2. Forage concentrations of Cu, Zn, Mn, and Mo in Study 1 and Mn, Mo, and Se in Study 2 were affected (P < 0.05) by pasture land preparation/planting methods in that these minerals were found to be lower from forages of sod-seeded treatments than from those of prepared seedbed treatments. Forage Cu concentrations were lower than the minimum requirements (10 ppm, DM) for beef cattle among months in both studies. Oats-ryegrass pastures of Study 2 had surprisingly low Fe concentrations (P < 0.01) in all months of the winter-spring grazing season. Cobalt, Mn, Mo, and Se did not vary much month to month during the winter-spring grazing months. All mean forage Se concentrations were lower than the requirements (0.10 ppm, DM) for grazing beef cattle. There were no differences (P > 0.05) in mean Se values between the two studies. Liver Cu, Fe, Co, and Se concentrations were sufficient to indicate adequate status of these minerals in tester animals from both forage types. Liver concentrations of Mn and Mo were slightly low, indicating a low status or these minerals. Plasma concentrations of Cu, Fe, Se, and Zn were all above the recommended concentrations for beef cattle. In conclusion, trace minerals deficient in North Florida during the cool season were Cu, Co, and Se, and a special consideration should be given to include adequate amounts while supplementing the mineral mixtures to growing beef cattle since forage samples reflected deficient concentrations of these minerals.     

Soil,forage, and serum nutrient changes as affected by deposition of volcanic sediments in northwestern nicaragua

Abstract

A study was carried out to determine the mineral status of grazing cattle as affected by the eruption of the Cerro Negro Volcano in northwestern Nicaragua. A total of 14 composite soil and forage samples and 30 blood samples were collected at each collection period, before (August 1991) and after (August 1992) the volcanic eruption. Higher soil levels of calcium (Ca), sodium (Na), manganese (Mn) (P<0.01), zinc (Zn) (P<0.05), and lower organic matter (OM) (P<0.01) were found after the volcanic eruption. Phosphorus (P) was the only macromineral found deficient with 93 and 71% of the samples below a critical level before and after volcanic eruption, respectively. Forage Ca, potassium (K), magnesium (Mg), P, Zn, copper (Cu), and selenium (Se) concentrations did not vary between collections. Forage crude protein (CP), in vitro organic matter digestibility [(IVOMD) P<0.05], cobalt (Co), Mn, and Na (P<0.01) were lower after the eruption. Iron (Fe) was the only mineral in forages that increased (P<0.01) after the volcanic eruption. Of the six minerals evaluated in serum only Ca and Mg concentrations were higher (P<0.05) after the volcanic eruption. The macrominerals more likely to be deficient in this area are P and Mg. Trace elements most likely to limit cattle productivity are Zn, Mn, Cu, Se, and Co. Special attention should be given to supplementation of Cu, since both plant and animal tissue samples reflected a deficiency of this mineral.     

广西常用饲料、牧草中铜、锌、铁、锰、钴、钼含量的初步调查

在广西54个县、市采集了81种常用饲料、牧草778个样本进行铜、锌、铁、锰、钴、钼6种微量元素分析,结果表明,这些微量元素的含量随饲料、牧草种类和地区的不同而有较大的差异。广西大多数饲料、牧草缺锌。铜、锰和铁的含量在谷类籽实较低。钴在大多数饲料中含量正常。钼的含量正常并低于中毒量6mg/kg。     

YIELD AND MINERAL CONCENTRATIONS OF SOUTHEASTERN UNITED STATES OAT CULTIVARS USED FOR FORAGE

A shift in oat (Avena sativa L.) production from grain to forage (hay and grazing) is occurring in the southeastern USA. However, most available cultivars were developed for improved grain production, rather than forage yield. We field tested several standard and new oat releases over 2 years, using repeated clippings to determine forage yield, nutrient uptake, and the potential to match plant nutrients with cattle mineral dietary needs. There were no differences in total annual forage yield among the tested cultivars within years but there was a difference between years. Forage tissue phosphorus (P), magnesium (Mg), and calcium (Ca) were sufficient, potassium (K), sulfur (S), and manganese (Mn) were excessive, and iron (Fe), copper (Cu), and zinc (Zn) were occasionally or frequently deficient to meet daily cattle dietary mineral needs. Sulfur, Cu, Fe, Zn, and Mn may be the most challenging to regulate in U.S. Coastal Plain soils at concentrations that satisfy both, oat and cattle nutritional requirements.     

The extractable trace element content of acid soils and the influence of pH,organic matter and clay content

Abstract

The analysis of extractable trace elements was carried out on 434 soils using 0.1 N HC1 as the extractant for copper, manganese, iron, zinc and cobalt, 0.2 M ammonium oxalate at pH 3.0 for molybdenum and boiling water for boron. Results indicated that on the average from about 1 to 20 percent of the total element content of the soil uas extractable, the percentage varying with the element. Comparing the amount of extractable elements in the 0–15 cm and 15–30 cm layers indicated that only manganese, zinc and boron were significantly different.

Correlation studies showed that the pH significantly influenced the quantity of manganese, iron, zinc and boron extracted, while organic matter influenced copper, manganese, zinc, cobalt and boron and clay content the copper, manganese, iron, zinc, cobalt and boron.     

Mineral concentrations of forages and soils in Benue State,Nigeria. I. Macrominerals and forage in vitro organic matter digestibility and crude protein concentrations

Abstract

Macromineral composition of different forage species and soils and forage in vitro organic matter digestibility (IVOMD) and crude protein concentrations in three agricultural zones of Benue State were studied. The zones consisted of Tiv zone (Zone A), Igala zone (Zone B), and Idoma zone (Zone C), each of which was made up of three sites. Site I was Fulani cattle migration routes across the state, site II represented grazing sites within home proximity, and site III were grazing reserves. Grazing animals were followed and forages corresponding to that consumed by them, and the corresponding soil samples were collected during the peak of the dry season (December‐January) and analyzed for nutrient composition. Forage IVOMD ranged from 21% to 79%, with values obtained in grass being lowest due to pronounced overmaturity. Only 10% of forage samples (exclusively from grasses), showed protein levels below the critical value of 7%. Most forage samples, as well as their corresponding soil samples were sufficient in calcium (Ca), magnesium (Mg), and potassium (K) concentrations. Soil concentrations of Ca, Mg, and K were particularly high compared to critical requirements in all the zones studied. Approximately 94% and 76% of forages were deficient in phosphorus (P) and sodium (Na), respectively, and the deficiencies were similar in all classes of forage and sites of study for each of the zones investigated. Results of forage‐soil relationships indicated low and nonexisting correlations; therefore soil analyzes are not of great importance in the assessment of available macromineral supplies to grazing livestock. The macrominerals most needed for supplementation of grazing livestock during the dry season are P, Na, and K.     

Monthly variation of forage and soil minerals in central Florida. I. macro‐minerals

Abstract

A two‐year study was conducted to determine the macromineral status of cattle grazed forages, mostly bahiagrass, and soils in central Florida. Soil and forage samples were collected every month for two years. Month differences (P < 0.01) were observed in all forage macrominerals and in crude protein (CP) for both years. No month effect (P > 0.05) was observed in IVOMD level during year 1. Year effects (P < 0.05) were observed in calcium (Ca), sodium (Na) and CP. Concentrations below the critical level were observed in all macrominerals studied. Higher forage macro‐mineral concentrations were found during spring‐summer months. In general, higher (P < 0.05) soil aluminum (Al), Ca, magnesium (Mg), phosphorus (P), and organic matter (OM) were observed during fall‐winter months, while Na was higher in winter. Soil Ca and Mg were adequate and potassium (K), Na and P were deficient. Year 2 showed higher (P < 0.05) soil macromineral concentrations. Correlation coefficients (r >|0.5|, P < 0.05) were present between forage K and forage CP (r = 0.557) and between forage P and forage CP (r = 0.554). Low correlations were found between soil and forage macrominerals. Percentages of total forage samples with macromineral and CP concentrations below critical levels (in parentheses) and suggestive of deficiency were as follow: in forage, Ca (0.30 ppm), 21%; Mg (0.18 ppm), 34%; K (0.60 ppm), 47%; Na (0.06 ppm), 89%; P (0.25 ppm), 85%; and CP (7%), 18%.     

新疆土壤微量元素的含量与分布

本文论述了新疆土壤中Fe,Mn,Zn,Cu全量和有效态含量及其分布.Fe的全量0.3-5.1%(平均值为2.4%),有效态含量0.16-504.00ppm(18.20ppm);Mn的全量59-1550ppm(564ppm),有效态含量0.38-41.60ppm(4.86ppm);zn的全量9-216ppm(75ppm),有效态含量0.08-11.84ppm(1.00ppm);Cu的全量5-145ppm(28ppm),有效态含量0.06-19.20ppm(1.22ppm).     

Composition and chemical changes during storage of fish meal from Capelin (Mallotus villosus)

The stability of fish meal depends on processing and storage conditions, but habitat and seasonal variations in composition and naturally occurring anti- and pro-oxidants may be equally important. Capelin meal from four different seasons was examined by measuring chemical composition and monitoring lipid oxidation during storage. The results revealed that lipid content was high in the summer but low in the spring. It was further demonstrated that among naturally occurring antioxidants, astaxanthin was high during summer, whereas alpha-tocopherol was highest in spring. Mineral content varied, with a high copper content in the summer, whereas iron, selenium, and zinc were highest in the winter. Measurements on the stability of capelin meal indicated a decrease in peroxide values, oxygen uptake, and thiobarbituric acid reactive compounds with storage, whereas browning and CO concentration increased with time. Rancidity was highest in autumn, but free fatty acids were highest during spring and summer.     

Effect of long-term application of farmyard manure on soil micronutrient status

In a long-term experiment conducted (1967?–?2001) at Hisar, India, pearl millet (Pennisetum typhoides) and wheat (Triticum aestivum) was grown during summer and winter in a rotation. The treatments consisted of farmyard manure (FYM) at the rate of 15, 30 and 45 Mg ha^???1 during one or both the seasons. A treatment without FYM was maintained as a control. This made the total number of treatments 10, along with 2 levels of nitrogen at 0 and 120?kg ha^???1. Samples from 0?–?15, 15?–?30 and 30?–?45?cm soil depths were collected and analysed for DTPA extractable and total content of zinc, iron, manganese and copper. Application of FYM significantly increased the DTPA extractable and total content of all the studied micronutrients in all soil depths. The increase was higher in the surface layer than in the lower depths. The time of application of FYM influenced the content of soil micronutrients. DTPA extractable and total content of micronutrients was higher when FYM was applied in winter as compared to summer. Application of N has no effect on DTPA extractable or total micronutrients content.     

Interrelationships of minerals in soil‐plant‐animal system at Kuti Ranch,Malawi

Abstract

An experiment was conducted in the central region of Malawi to study the relationship of minerals in soil‐plant‐animal systems to enable prediction of mineral status of beef cattle. Soil, forage and tissues (blood, bone and liver biopsy samples) were collected from cows at the same time in February, April, May, October and December for three consecutive years. Brahman x Malawi Zebu cows were supplemented with mono‐ and di‐calcium phosphate, salt and copper (plus cobalt and selenium) boluses.

Bone, liver and serum minerals (calcium, phosphorus, copper and zinc) correlated poorly to specific minerals in either forage or soil. A few minerals could explain more than 16% of their variation in animal tissues. Consequently, it was concluded that correlation coefficients among soil, plant and animal tissues are low or nonexistent. Therefore, until high, significant, reliable and reproducible correlation coefficients are established among soil, plant animal tissues, prediction of mineral status of animals by regression analysis from mineral content of soil or plants is likely to remain imperfect.