Studies in grazing management V. Further determination of the nutrient intake of dairy cows under close-folding and rotational methods of grazing

1952 ◽  
Vol 42 (3) ◽  
pp. 314-321 ◽  
Author(s):  
R. Waite ◽  
W. Holmes ◽  
J. Boyd

1. The experiments started in 1949 to determine the weight and chemical composition of the herbage dry matter eaten by two groups of dairy cows grazing under a rotational and a close-folding system of management have been continued in 1950.2. Good-quality herbage was fed in adequate quantity to both groups for 20 weeks, in four fiveweekly periods allowing a double change-over system for the groups. The weights of protein, fibre, other extractives, lignin and minerals eaten daily by the close-folded group were determined. Difficulty in obtaining truly representative herbage samples from the rotational paddock made such detailed analyses for the rotationally grazed cattle not worth while.3. The weight of dry matter eaten by the closefolded cows was remarkably constant, the mean was 26 lb./cow/day and the standard deviation ±2·7 lb. The weight eaten by the rotationally grazed cows was more difficult to measure and appeared to vary considerably, the average being 31 lb. dry matter/ cow/day, and the standard deviation ±3·1 lb. Reasons are suggested why this figure of 31 lb. may be at least 5% too high.4. The relationship between the chemical composition of herbage as cut for sampling and the probable composition of the herbage as eaten by the grazing animal is discussed. Correction curves are given to convert the protein and fibre contents of herbage as cut in these experiments to values corresponding to those in the herbage as eaten.5. An attempt has been made to provide a balance sheet, in terms of D.C.P. and S.E., of animal production against nutrient intake. A deficiency of both protein and energy existed during the first spring period in both 1949 and 1950 (according to presentday standards), and although the protein balance became positive later in the season, the energy provided by the grass eaten was still barely adequate.6. Mineral balances calculated for the closefolded cows showed deficiencies of both calcium and phosphorus during the period of high milk yield, with the balances becoming positive later in the grazing season.

1999 ◽  
Vol 132 (2) ◽  
pp. 163-172 ◽  
Author(s):  
M. FIELD ◽  
D. WILMAN ◽  
D. J. C. JONES

The paper reports a study of the chemical composition of 25400 grass silages produced in England and Wales, of which 1040 were from the period 1961–63, 17900 (15480 clamped and 2420 baled) were from 1982–88 and 6460 (5640 clamped and 820 baled) were from 1992–93. A sample of each silage had been analysed for dry matter (DM), pH, crude protein (CP) and volatile N and in most cases for ash.The baled silages were drier on average than the clamped silages, with a wider spread of DM contents. The clamped silages with the lowest pH on average were those with a DM content of c. 240 g/kg; clamped silages wetter than this were progressively higher in pH with reduction in DM content; clamped and baled silages drier than 240 g/kg were progressively higher in pH with increase in DM content, up to pH 5·9 in baled silages of 580 g DM/kg. At a given DM content pH was on average 0·6 units higher in baled than in clamped silages. The ash content of baled silages was similar to that of clamped silages. There was an increase in the mean CP content of clamped silages between 1961–63 and 1992–93 and a reduction in the proportion of CP which was volatile. The relationship between DM and volatile N as a proportion of total N was a curve rather than a straight line, with the steepest part of the curve at the lower end of the DM range. The wet silages harvested in 1961–63 were particularly high in volatile N. At a given DM content in the range 170–320 g/kg, volatile N was rather higher in baled than in clamped silages in both 1982–88 and 1992–93. Clamped silages with a DM content of at least 250 g/kg and baled silages with a DM content of at least 310 g/kg were typically well preserved in the sense of having <100 g volatile N/kg total N.


1962 ◽  
Vol 4 (3) ◽  
pp. 351-358 ◽  
Author(s):  
K. L. Blaxter ◽  
R. S. Wilson

1. Four roughages were given ad lib. to each of eight steers. The amount consumed and the apparent digestibility of the energy of each roughage were determined together with the weight gains of the steers.2. The mean voluntary intake of dry matter was related to the mean apparent digestibility of the energy of the roughages in the same quantitative way for the steers as had been noted with sheep. Mean weight gains were proportional to the mean number of calories of energy apparently digested.3. Significant differences between individuals occurred in their voluntary food intakes, and those animals which consumed most digested it least efficiently. The variation in intake from individual to individual expressed as a standard deviation was ±7·5% of the mean.4. The quantitative similarity of sheep and cattle as far as the relationship between their voluntary consumption of food of different apparent digestibility is concerned, is contrasted with their dissimilarity with respect to fasting metabolism. It is suggested that sheep are likely to prove more efficient convertors of the energy of roughages to body gain than are cattle.Further work is clearly necessary to explore the extent of these differences.


2017 ◽  
Vol 12 (2) ◽  
Author(s):  
Putri Anggreni

<p>Achievement motivation is an encouragement in a person to do a particular task or activity or task as well as possible in order to achieve a commendable achievement with honors. Seeing these indications, the performance of employees in the Motor Car Autotama Karangasem is influenced by several variables. One of them is the achievement motivation, but how much the relationship or the determination of achievement motivation on employee performance Autotama Motor Cars is not certain. Therefore, this study will examine the determination of achievement motivation on employee performance Autotama Car Motor Karangasem Data achievement motivation and performance of employees that have been collected tabulated the mean, median, mode, the range, scale and standard deviation of data concerning achievement motivation and performance of employees. Statistical analysis was used to test the hypothesis with a simple linear regression. The stages of the analysis conducted in this study is a description of the data. Qualification data description achievement motivation and performance of employees, also using univariant analysis. This analysis is based on the average score of the ideal (Mi) and the ideal standard deviation (SDi). As well as this analysis also includes testing requirements analysis and hypothesis testing. The analysis showed that there was a significant correlation between the Achievement Motivation Employee Performance through the equation of the line y = -36.800 + 0.632 X with Freg = 43.015 (p &lt;0.05). In the present study found a significant correlation between the achievement motivation employee performance at 0.691 with p &lt;0.05. This means that the better the achievement motivation of employees, the better the performance of the employee. Achievement motivation variables could explain the higher performance of employees amounted to 47.8%. These findings indicate that achievement motivation has an important role in improving employee performance. Normatively found that achievement motivation as very good in the category means an employee has shown excellent achievement motivation in carrying out his job. From the correlation analysis it is evident that significant determination between the achievement motivation employee performance. It needs to be maintained to keep employees comfortable and satisfied in performing everyday tasks so that corporate objectives will be achieved.<br />Key Words: achievement motivation, employee performance, Autotama Motor Cars, corporate objective</p>


2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Leila Shafie Bafti ◽  
Maryam Alsadat Hashemipour ◽  
Hamidreza Poureslami ◽  
Zeinab Hoseinian

The aim of the present study was to evaluate the relationship between BMI and tooth decay in a population of Iranian children. In this cross-sectional descriptive/analytical study, 1482 children were selected from kindergartens and preschool centers in Kerman, Iran. The children underwent examination of deciduous teeth (using the dmft index) after determination of height and weight for calculation of BMI. The relationship between BMI (after adjustment for age) and dmft was determined using Poisson’s regression model. The mean of dmft in children with normal BMI was 1.5-fold that in subjects with extra body weight. Age had a significant effect on dmft. In addition, dmft was higher in boys compared to girls. The results of the present study showed that caries rate in the deciduous teeth of 3–6-year-old children decreases with an increase in body weight.


1982 ◽  
Vol 16 (3) ◽  
pp. 240-243
Author(s):  
Wayne T. Corbett ◽  
Harry M. Schey ◽  
A. W. Green

The mean and standard deviation over 24 h for 3 groups of animals - active, intermediate and inactive - in physical activity units were 10948 ± 3360, 2611 ± 1973 and 484 ± 316 respectively. The differences were significant ( P = 0·004), demonstrating the ability of the method to distinguish between groups that can be visibly differentiated. The small within-animal physical activity standard deviation (18·85 PAU) obtained in another group, suggests that it also yields reliable physical activity measurements for non-human primates. The monitoring device used can discriminate between individual nonhuman primate physical activity levels in a free-living environment and does not alter daily behaviour. This makes possible the study of the relationship between physical activity and atherosclerosis in nonhuman primates.


1973 ◽  
Vol 56 (5) ◽  
pp. 1164-1172
Author(s):  
Milan Ihnat ◽  
Robert J Westerby ◽  
Israel Hoffman

Abstract The distillation-spectrophotometric method of Hoffman for determining maleic hydrazide has been modified to include a double distillation and was applied to the determination of 1–30 ppm maleic hydrazide residues in tobacco and vegetables. Recoveries of 1–23 μg added maleic hydrazide were independent of weight of maleic hydrazide, but did depend on sample and sample weight. The following recoveries were obtained from 0.5 g sample: pipe tobacco, 84%; commercially dehydrated potato, 83%; cigar tobacco, 81%; dried potato, 76%; fluecured tobacco, 73%; dried carrot, 71%. In the absence of sample, the recovery was 82%. When appropriate standard curves were used, maleic hydrazide levels determined in tobacco samples were essentially independent of sample weight in the range 0.1–3 g. The mean relative standard deviation for a variety of field-treated and fortified tobacco samples containing 1–28 ppm maleic hydrazide was 3%. The precision and sensitivity of this procedure seem to be substantial improvements over official method 29.111–29.117. It is recommended that the present method be subjected to a collaborative study.


1979 ◽  
Vol 42 (1) ◽  
pp. 89-96 ◽  
Author(s):  
N. F. Suttle

1. The minced carcases of twenty-seven lambs, ranging from 18 to 69 kg in live weight, and twenty-five calves (30–90 kg) were analysed for copper, iron, manganese and zinc. The lambs were weaned whereas the calves were reared exclusively on milk.2. Mean concentrations of Fe, Mn and Zn for groups of lamb carcases fell within the ranges 52.6–75.1, 0.7–1.2 and 20.8–25.6 mg/kg fresh carcase weight respectively. The concentrations of Fe and Mn decreased while that of Zn increased slightly with age at slaughter. The concentrations of Fe, Mn and Zn in calves were close to thosein lambs.3. For both species, the concentration of Cu in the carcase varied erratically: variation in hepatic Cu storage was implicated. In an additional study of ten full-term foetuses from Cu-depleted or Cu-supplemented ewes, a dietary Cu supplement (10 mg/kg dry matter (DM)) increased foetal Cu status 10-fold, due largely to an increase in foetal liver Cu.4. The mean retentions of trace elements in the lamb carcases (%intake) were approximately: Cu 2.0, Fe 1.3, Mn 0.08, Zn 4.0. The corresponding values for the milk-fed calves were all probably much higher (Cu 23, Fe 43.7, Mn 4.9, Zn 34.0) but Cu intake was not accurately measured.5. After allowing for tissue storage of Fe and Mn, values of 55, 0.85 and 24 mg/kg carcase gain were taken to represent the approximate net growth requirements of lambs for Fe, Mn and Zn respectively: the corresponding value for Cu was probably < 1.0 mg/kg. Values for calves were similar to those for lambs.6. It was concluded that the total net requirements of ruminants for Fe and Zn shouldbe considered in terms of daily intakes of the metans rather than dietary concentrationsbecause of the relatively large and constant contribution of the growth component to thetotal requirement.


1970 ◽  
Vol 75 (2) ◽  
pp. 213-222 ◽  
Author(s):  
K. R. Christian ◽  
D. B. Jones ◽  
M. Freer

SUMMARYBulk harvests of primary growth were made at intervals during the spring and summer of 2 consecutive years from an ungrazed area of lucerne (Medicago sativa) and the digestibility by sheep was measured. At the same times, shoots of known length representative of the sward were collected, divided into 7·5 cm lengths, and separated into leaf and stem for the determination of ash, nitrogen, cellulose, and in vitro organic matter digestibility.Digestibility and leaf: stem ratio of the bulk harvests decreased and dry matter increased as the season advanced. Leaf composition changed little, but stem increased in lignin and decreased in ash and in vitro digestibility. In vitro digestibility and leaf: stem ratio were highly correlated with sheep digestibility.Chemical composition of shoots of known heights was similar to that of the bulk harvests. Leaf weights/shoot tended to increase linearly with height of shoot, whereas stem increased nearly as the square of the height. Dry matter of leaf and stem were inversely related to leaf:stem ratio. Stem digestibility decreased with leaf:stem ratio and with increase in shoot height.Chemical components of shoot fractions were associated with each other and were largely dependent on the distance from the top of the shoot at which they had been taken, irrespective of shoot height or time of year. Bottom stems had lower ash, nitrogen and digestibility but higher cellulose, dry weight and dry matter than top stems, whose composition approached that of leaves. Leaf fractions showed little consistent trend with position on the shoot.Some of the difficulties in studying changes in plant composition under field conditions are discussed.


1974 ◽  
Vol 57 (2) ◽  
pp. 368-372 ◽  
Author(s):  
Milan Ihnat

Abstract A fluorometric method using 2,3-diaminonaphthalene for estimating selenium has been evaluated with regard to its applicability to food samples. Charring of the sample during digestion appeared to result in losses of native and added selenium from some samples, so a modified wet digestion procedure was introduced. Digestion first in nitric acid followed by a mixture of nitric-perchloric-sulfuric acids substantially reduced the incidence of sample charring for a variety of foods. The mean apparent recovery of selenium added as selenite or selenate at 100 and 500 ng levels to 0.1 and 1.0 g corn cereal, skim milk powder, and meat and 0.1 g fish was 101.0%; the actual recovery of the same levels of selenium from standard solutions was 96.6%. For a variety of samples containing 5—750 ng native or added selenium, the standard deviation as 4.7 + 1.95 X 10-2W ng, where W = ng selenium in the sample taken for analysis. The relative standard deviation (RSD) as a function of selenium weight (ng) was 50% (10), 6.7% (100), 4.3% (200), 3.1% (400), 2.7% (600), and 2.5% (800). The detection limit (weight of selenium at which RSD = 50%) was 10 ng at a mean blank level of 25 ng.


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