The use of faecal nitrogen as an index for estimating the consumption of herbage by grazing animals

Data from thirty-five digestibility trials with sheep in metabolism cages were used to investigate statistically the relationships between organic matter intake (I), faecal organic matter output (F), and the nitrogen concentration in faecal organic matter (N).The data fell easily into groups due to botanical or seasonal differences in the feed. These groups of data were homogeneous and provided highly significant linear equations of the forms I = bF + cFN and I = a + cFN. When compared these groups of data sometimes showed differences in slope, position or both. A quadratic expressionI = bF + cFN + dFN2was found to accommodate a majority of the data but to be less precise than I = a + cFN.A further expression incorporating N as an independent variable was also examined,I = a + cFN2 + eN.This expression, although far from being universally adequate, proved to be generally better than existing formulae. When applied to the data of Greenhalgh et. al. (1960), it substantially reduced heterogeneity between data for spring and data for summer pastures.Causes of variation in the relationship between organic-matter intake and nitrogen in faeces, and some of the hazards of extrapolation from empirical regression relations, are discussed.

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The indirect estimation of the digestibility of pasture herbage I. Nitrogen and chromogen as faecal index substances

The Journal of Agricultural Science ◽

10.1017/s002185960002325x ◽

1960 ◽

Vol 55 (3) ◽

pp. 371-376 ◽

Cited By ~ 33

Author(s):

J. F. D. Greenhalgh ◽

J. L. Corbett

Keyword(s):

Organic Matter ◽

Nitrogen Concentration ◽

Regression Equation ◽

Seasonal Differences ◽

Indirect Estimation ◽

Faecal Nitrogen ◽

Standard Deviations ◽

The Difference ◽

The Relationship ◽

Single Regression

1. In seventeen digestibility trials carried out between May and November, 1957, groups of three steers were fed on fresh herbage, cut mainly from mixed swards. Herbage digestibility and the concentrations in faeces of the index substances nitrogen and chromogen were measured over periods of 5 days. Organic matter digestibility ranged from 61·2 to 78·9%.2. The relationship between herbage digestibility and faecal nitrogen concentration could not be described satisfactorily by a single regression equation for all trials, and separate equations were calculated for (a) first-growth herbage and (b) aftermath (second and third growths). For a given faecal nitrogen concentration herbage digestibility was about five units higher for first-growth than for aftermath herbage.3. For the faecalchromogen-digestibilityrelationship the difference between growths was even greater and, again, two equations were required. In most trials the quantity of chromogen excreted was apparently greater than the quantity consumed.4. The ‘seasonal’ differences in faecal index relationships were caused by the fact that later growths of herbage contained considerably greater concentrations of nitrogen and chromogen than did firstgrowth herbage of the same digestibility. There was also some evidence that the relationships may be affected by the application of nitrogenous fertilizers to the sward.5. In order to avoid biases in the indirect estimation of herbage digestibility it appears important to use different regressions for different growths. Although such regressions would be restricted in their application they are likely to be more precise than general equations. In these trials both nitrogen and chromogen regressions had low residual standard deviations of ± 1·5 units of digestibility.

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The use of chromium oxide and faecal nitrogen concentration to estimate the pasture intake of Merino wethers

Australian Journal of Agricultural Research ◽

10.1071/ar9630257 ◽

1963 ◽

Vol 14 (2) ◽

pp. 257 ◽

Cited By ~ 18

Author(s):

LJ Lambourne ◽

TF Reardon

Keyword(s):

Organic Matter ◽

Feed Intake ◽

Nitrogen Concentration ◽

Linear Equations ◽

Large Measure ◽

Feed Digestibility ◽

Wide Range ◽

Digestible Organic Matter ◽

Faecal Nitrogen ◽

Maintenance Requirements

Statistical analysis of the results of digestion trials on a wide range of fresh pasture herbages shows that their digestibility might be estimated as the intake factor or feed faeces ratio (Y) from the equation: YO.M. = (2.04 – 0.24XN ± 0.186X2N) ± 0.53 where YO.M. is the intake factor for organic matter, and XN is the percentage of nitrogen in faecal organic matter. The results were subdivided arbitrarily into "summer" (September–April) and "winter" (May–August) periods, and these proved to yield significantly different linear equations. The summer regression yielded higher intake factors (corresponding to 2–3% higher digestibility) for a given value of faecal nitrogen percentage. This subdivision reduced the standard deviation from regression only slightly, to about 0.50, which amounts to ± 17% for pasture of 75% digestibility. These equations give considerably lower values of digestibility for a given nitrogen concentration than regressions hitherto published. The present pooled equation, based on short leafy herbage, probably gives sounder estimates for grazing sheep than do the existing equations derived from trials with more mature herbages. When sheep with a wide range in body weight were all fed a maintenance ration, it was found that feed digestibility was not detectably reduced at high levels of feeding. The undoubtedly higher feed intake of grazing than of pen-fed animals, due in large measure to their higher maintenance requirements, therefore may not cause the reduction in digestive efficiency, and thus the bias in estimates of feed intake, that has been supposed. On the basis of the pooled regression, which is felt to be preferable to a subjectively selected "seasonal" equation, estimates of the intake of digestible organic matter (D.O.M.) by sheep in metabolism pens fed on fresh pasture herbage averaged 97 ± 22% of the true figures, or ± 80 g D.O.M.

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The indirect estimation of the digestibility of pasture herbage III. Regressions of digestibility on faecal nitrogen concentration: effects of species and individuality of animal and of the method of determining digestibility upon the relationships

The Journal of Agricultural Science ◽

10.1017/s0021859600005967 ◽

1963 ◽

Vol 61 (2) ◽

pp. 221-226 ◽

Cited By ~ 11

Author(s):

J. P. Langlands ◽

J. L. Corbett ◽

I. McDonald

Keyword(s):

Organic Matter ◽

Dry Matter ◽

Nitrogen Concentration ◽

Regression Coefficients ◽

Regression Equations ◽

Concentration Effects ◽

Animal Data ◽

Faecal Nitrogen ◽

Relationship Of ◽

The Relationship

1. A 36-day continuous digestibility trial with three steers and three sheep fed fresh pasture herbage was carried out during May and June, 1960. For all animals the digestibilities of herbage organic matter (O.m.) were estimated both by collection of faeces and by administering standard quantities of chromium sesquioxide (Cr203) twice daily and determining concentrations of Cr203 in faeces. In a further 36-day trial during August and September 1960, three steers and three cows were used; with the steers, digestibilities were estimated by both methods but with the cows by the Cr203 method only.2. Regression equations were obtained relating O.m. digestibility to the percentage of nitrogen (N) in faecal O.m. When digestibilities were estimated by the same method the same regression coefficients could be fitted to the data from each of the steers and sheep in the spring trial. A similar result was found with the data from each of the steers and cows in the summer trial.3. In each equation different constant terms were required for each animal, which differed significantly between individuals but not between species or class of animal. Data obtained from an examination of the relationship of g. N excreted per 100 g. feed dry matter to g. N intake per 100 g. feed dry matter indicated that differences between the constant terms could be linked with variations between animals in the excretion of metabolic faecal N.

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Studies of natural herbage of the sub-tropics I. The digestibility of herbage grazed by cattle

The Journal of Agricultural Science ◽

10.1017/s0021859600013241 ◽

1962 ◽

Vol 58 (3) ◽

pp. 387-391 ◽

Cited By ~ 10

Author(s):

J. H. Topps

Keyword(s):

Organic Matter ◽

Dairy Cattle ◽

Protein Content ◽

Crude Protein ◽

Nitrogen Concentration ◽

Crude Protein Content ◽

Faecal Nitrogen ◽

Digestible Crude Protein ◽

Cattle Faeces ◽

Organic Matter Digestibility

1. In two continuous digestibility trials carried out in 1960 and 1961, groups of three wether sheep were fed on oven-dried herbage which had been selectively collected from natural pastures during December 1959 to March 1960 and December 1960 to March 1961. The organic matter digestibility and the digestible crude protein content of the herbage and the nitrogen concentration in faeces were measured over periods of 5 days. The fresh faeces of dairy cattle grazing the natural pastures were regularly sampled and analysed. Regressions of organic matter digestibility and digestible crude protein content on faecal nitrogen were evaluated. From these equations and the composition of the dairy cattle faeces the digestibility of the herbage grazed was calculated.2. The herbage consumed by the cattle had a significantly higher organic matter digestibility and digestible crude protein content than the collected material. This difference, which increased as the season progressed, indicates that dairy cattle became increasingly selective in their grazing as the pasture deteriorated in quality.3. There was a marked yearly difference in digestibility-faecal nitrogen relationships and in the quality of the consumed forage. The grass eaten in 1959-60 had a higher digestibility and lower digestible crude protein content than in the following year. These differences may be part attributable to a seasonal difference in rainfall.4. The organic matter digestibility of the grazed herbage ranged from 52·71 to 65·03% and the digestible crude protein content from 3·08 to 7·43% For milk production, the herbage consumed is low in digestible protein in relation to the total amount of digestible nutrients.

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Modeling Continuous Non-Linear Data with Lagged Fractional Polynomial Regression

Asian Journal of Applied Sciences ◽

10.24203/ajas.v6i5.5492 ◽

2018 ◽

Vol 6 (5) ◽

Author(s):

Kazeem Kehinde Adesanya ◽

Abass Ishola Taiwo ◽

Adebayo Funmi Adedodun ◽

Timothy Olabisi Olatayo

Keyword(s):

Coefficient Of Variation ◽

Polynomial Regression ◽

Estimation Method ◽

Likelihood Estimation ◽

Fractional Polynomial ◽

Non Linear ◽

Unit Increase ◽

Independent Variable ◽

The Relationship ◽

Better Than

Fractional Polynomial regression is a form of regression analysis in which the relationship between the independent variable and the dependent variable is modelled as a 1/nth degree polynomial. Thus, this work is used to propose an extension of Fractional Polynomial Regression (FPR) term Lagged Fractional Polynomial Regression (LFPR) which is an alternative method to traditional techniques of analysing the pattern and degree of relationship between two or more continuous non-linear data. The coefficients of the proposed method were estimate using Maximum Likelihood Estimation method. From the results, the LFPR model indicated that for a unit increase in Evaporation, Humidity and Temperature there will be an increase in the millimeter of rainfall series on yearly basis. The value of coefficient of variation (R2) for the LFPR and FPR were 99% and 77%. While the value of adjusted Coefficient of Variation (R2) for LFPR and FPR were 96% and 75% respectively. Hence, the proposed method outperformed and adequately explained the variation in the dependent variable better than Fractional Polynomial Regression based on the values (R2) and adjusted (R2).

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Effect of environment on the maintenance requirements of Merino wethers

Australian Journal of Agricultural Research ◽

10.1071/ar9630272 ◽

1963 ◽

Vol 14 (2) ◽

pp. 272 ◽

Cited By ~ 21

Author(s):

LJ Lambourne ◽

TF Reardon

Keyword(s):

Small Groups ◽

Nitrogen Concentration ◽

Daily Intake ◽

Cost Of Locomotion ◽

Digestible Organic Matter ◽

Faecal Nitrogen ◽

Maintenance Requirements ◽

The Relationship ◽

Energy Cost Of Locomotion ◽

Stimulation Of

Small groups of Merino wethers were maintained at virtually constant liveweight in four "environments" and their maintenance feed requirements estimated from the relationship between their fluctuations in liveweight over 14-day periods and their feed intakes, measured directly or estimated by chromium oxide dilution and faecal nitrogen concentration. When adult wethers of equal size but a varying degree of fatness were fed on fresh pasture herbage in metabolism pens, liveweights of 26, 32, and 46 kg could be maintained on a daily intake of approximately 200, 300, and 420 g digestible organic matter (D.O.M.) respectively. When the metabolism pens were placed outdoors in winter the maintenance requirements rose, the rise appearing to be greatest for the thin sheep. When wethers were allowed to graze for about 1½ , 2½, and 4 hr in abundant pasture, liveweights of 26, 33, and 46 kg were maintained on intakes of approximately 420, 480, and 490 g D.O.M. respectively. When the same wethers were allowed to graze freely and weight was controlled by the scarcity or abundance of the pasturage, the same liveweights were maintained on intakes of about 750, 780, and 560 g D.O.M. respectively. The rise in maintenance requirements on short pasture seems too great to be explained by the increased energy cost of locomotion and grazing. The possibility of an endocrine stimulation of metabolic rate is pointed out.

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The Inflorescence and Fruit Peduncle as Indicators of Nitrogen Status of the Avocado Tree

HortScience ◽

10.21273/hortsci.39.6.1173 ◽

2004 ◽

Vol 39 (6) ◽

pp. 1173-1174 ◽

Cited By ~ 7

Author(s):

Bruno Razeto ◽

Jorge Salgado

Keyword(s):

Fruit Set ◽

Nitrogen Concentration ◽

Persea Americana ◽

Metropolitan Region ◽

Tissue Analysis ◽

Nitrogen Status ◽

Kjeldahl Digestion ◽

Hass Avocado ◽

The Relationship ◽

Better Than

A tissue analysis trial for the diagnosis of nitrogen level was performed during the 2001 growing season in Paine County, Metropolitan Region, Chile. Seven-year-old `Hass' avocado (Persea americana Mill.) trees were soil treated with urea at rates of 0, 333, 666, and 999 g N/tree, split in two applications (2 and 4 months after fruit set). Each treatment was applied to three randomly selected trees. Fifty spring flush leaves and fifteen fruit peduncles were taken per tree 4 months after application. Two months later, 70 panicles per tree were taken, and nitrogen concentration in these samples was determined by Kjeldahl digestion. Differences between treatments were better detected in peduncle and inflorescence samples than in leaf samples. The relationship between nitrogen dose and nitrogen concentration in the tissue was R2 = 0.67, 0.65, and 0.56 in peduncle, leaf, and inflorescence, respectively. Consequently, peduncle appears a promising tissue, probably better than leaf, for diagnosing the nitrogen status of avocado trees.

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The influence of Herzberg’s motivator factor on employees’ organizational citizenship behaviour

ADVANCES IN BUSINESS RESEARCH INTERNATIONAL JOURNAL ◽

10.24191/abrij.v2i1.10039 ◽

2016 ◽

Vol 2 (1) ◽

pp. 1

Author(s):

Noorlaila Yunus ◽

Cairul Azwa Azimi

Keyword(s):

Organizational Citizenship ◽

Significant Relationship ◽

Civic Virtue ◽

Negative Influence ◽

Western Countries ◽

Achievement Growth ◽

Independent Variable ◽

Research Questions ◽

The Relationship

Organizational Citizenship Behaviour (OCB) has been widely studied across the boarders especially in the western countries. This workplace voluntary behaviour is associated with many predictors that may bring whether major, minor or negative influence towards the engagement of employees’ OCB. Basically, this study is focusing on motivation as the predictor or independent variable that influence employees’ engagement on the OCB (altruism, conscientiousness, courtesy, civic virtue and sportsmanship) behaviour. Herzberg’s motivator factor (achievement, advancement, recognition and growth) has been chosen as the independent variable. A total of 150 questionnaires were distributed conveniently to respondents. With 125 questionnaires returned, researcher was able to analyze the data based on the research questions and hypotheses developed. The findings showed moderate and weak, significant relationship between the variable excluding the relationship between independent variable and civic virtue and sportsmanship. Thus, Herzberg’s motivator factor was not a predictor to civic virtue and sportsmanship behaviour. However for the strongest predictor; achievement, growth and growth are strongly predicts the altruism, conscientiousness and courtesy behaviour respectively. However, with the absence of relationship between independent variable and civic virtue as well as sportsmanship, therefore the strongest predictor cannot be determined as the value recorded was below the criterion.

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Analisa Pemilihan Moda Transportasi Umum Rute Tanjung Karang – Bandara Radin Inten II Dengan Stated Preference dan Uji Crame’s V

Borneo Engineering : Jurnal Teknik Sipil ◽

10.35334/be.v2i2.621 ◽

2018 ◽

Vol 2 (2) ◽

pp. 137

Author(s):

Muhammad Abi Berkah Nadi

Keyword(s):

Regression Analysis ◽

Utility Function ◽

Stated Preference ◽

Technical Analysis ◽

Chi Square ◽

Time Headway ◽

Independent Variable ◽

The Relationship ◽

Selection Of

Radin Inten II Airport is a national flight in Lampung Province. In this study using the technical analysis stated preference which is the approach by conveying the choice statement in the form of hypotheses to be assessed by the respondent. By using these techniques the researcher can fully control the hypothesized factors. To determine utility function for model forecasting in fulfilling request of traveler is used regression analysis with SPSS program. The analysis results obtained that the passengers of the dominant airport in the selection of modes of cost attributes than on other attributes. From the result of regression analysis, the influence of independent variable to the highest dependent variable is when the five attributes are used together with the R square value of 8.8%. The relationship between cost, time, headway, time acces and service with the selection of modes, the provision that states whether or not there is a decision. The significance of α = 0.05 with chi-square. And the result of Crame's V test average of 0.298 is around the middle, then the relationship is moderate enough.

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