A survey of some in vitro methods used for animal nutrition research and extension work in Europe: the differences between the references and the truth

1998 ◽  
Vol 22 ◽  
pp. 338-340
Author(s):  
C. R. Mills
Keyword(s):  
Crude Protein ◽  
Rumen Fluid ◽  
Animal Nutrition ◽  
Concerted Action ◽  
In Vitro Methods ◽  
Nutrition Research ◽  
Extension Work ◽  
Nutritional Needs

As animal nutritionists are generally very cautious about using chemical analysis only for defining nutritional needs for livestock and as in vivo experiments are long, costly and subject to animal welfare legislation, much emphasis is placed on various in vitro analyses which are often regarded as being very informative in the absence of in vivo data. In vitro analyses may be applied to dry- (DMD) and organic-matter (OMD) digestibility and crude protein (CP) degradability (DG) and may involve ‘live’ cultures such as rumen fluid or gastric juices or ‘dead’ extracts containing enzymes. As part of an EU-funded Concerted Action (see Acknowledgements), a survey of the methods adopted for in vitro determinations (in vitro OMD, in vitro DG) for ruminants, pigs and poultry is underway: this paper presents a progress report of the information received to date concerning ruminant methods.The participants in the Concerted Action were asked to provide details of the in vitro methods actually in use in their countries, with particular attention to the methods used by the so-called Feed Information Centres (i.e. Feed Evaluation Units) for routine analyses (i.e. not experimental work). The participants supplied details of modifications and/or references to methods and this information was collated and circulated for checking and comment.

scholarly journals In vitro estimation of rumen fermentable organic matter using rumen fluid and a cell free preparation of rumen fluid

1994 ◽  
Vol 42 (4) ◽  
pp. 343-356 ◽  
Author(s):  
J.W. Cone ◽  
A.H. Van Gelder ◽  
E.T. Veerman ◽  
A.M. Van Vuuren
Keyword(s):  
Organic Matter ◽  
Rumen Fluid ◽  
Good Prediction ◽  
Feed Composition ◽  
In Vitro Methods ◽  
In Situ Method ◽  
A Cell

The amount of microbial protein leaving the rumen is considered as a function of the amount of rumen-fermentable organic matter (FOM) in the rumen. FOM can be calculated using tables, or estimated by in situ incubation, but both methods have some drawbacks. In vitro methods were therefore developed to estimate FOM, using fresh rumen fluid or a cell-free preparation of rumen fluid. Results were compared with the in situ method and a method using chemical feed composition. The in vitro methods gave a good prediction of the in situ estimation of FOM for the majority of feeds. For some feeds rich in starch or fat, the correlation was poor. Because no in vivo data of FOM were available, it could not be determined whether the in vitro or in situ methods gave false results. However, arguments suggest that the in situ method is not suitable for some feeds.

In vitro methods as predictors of voluntary intake and digestibility of hays fed to sheep

2002 ◽  
Vol 53 (4) ◽  
pp. 471 ◽  
Author(s):  
M. D. Carro ◽  
S. López ◽  
J. S. González ◽  
F. J. Ovejero ◽  
M. J. Ranilla
Keyword(s):  
Degradation Rate ◽  
Rumen Fluid ◽  
Predictive Ability ◽  
Gas Production ◽  
Regression Equation ◽  
Multiple Regression Equation ◽  
In Vitro Methods ◽  
First Order Kinetics

Eleven sun-cured hays were used to study the suitability of different in vitro methods to predict their voluntary dry matter (DM) intake (VDMI; g DM/kg liveweight) and in vivo DM digestibility (DMD; g/kg). The methods used were: (1) gas production at different incubation times when hays were incubated in vitro with buffered rumen fluid, (2) DM disappearance at different incubation times with cellulase (CEL), (3) release of sugars to the supernatant after incubation with cellulase, and (4) optical density of the supernatant at λ = 280 nm (as an indicator of phenolic compounds release) after incubation with cellulase. All kinetic data were fitted to first-order kinetics models to estimate the rate of degradation and the potential degradability, and the average degradation rate and effective degradability (ED) were calculated. The most accurate prediction of VDMI was by using the average degradation rate of the CEL method in a single regression equation, which accounted for 0.78 of the variation in intake (residual s.d. = 1.40). When only data from grass-rich hays were considered, the inclusion of potential degradability and rate of degradation of the CEL method in a multiple regression equation accounted for 0.98 of the variation in intake (residual s.d. = 0.32). The ED of the CEL method explained 0.93 and 0.92 of the variation in the in vivo DMD for all hays and grass-rich hays, respectively (residual s.d. = 18.1 and 21.7, respectively). The predictive ability of the different methods is discussed and compared with that of the in situ technique that has been previously reported.

A comparison of near infra-red reflectance spectroscopy with three in vitro digestibility methods to predict digestibility in vivo in cereal straws

1989 ◽  
Vol 1989 ◽  
pp. 49-49 ◽  
Author(s):  
D I Givens ◽  
Jeannie M Everington ◽  
C K Baker
Keyword(s):  
Cell Wall ◽  
Predictive Power ◽  
Rumen Fluid ◽  
Predictive Ability ◽  
Reflectance Spectroscopy ◽  
In Vitro Digestibility ◽  
In Vitro Methods ◽  
Infra Red

There have been many attempts to use the measurement of cell wall fractions to predict the digestibility in vivo of untreated and alkali treated straws (see far example Sundstøl et al, 1978; Reid and Ørskov, 1987). All these attempts have shown this approach to have very low predictive ability for straws. Accordingly extensive use has been made of digestibility measurements in vitro using either rumen fluid (eg Sundstøl et al, 1978) or cellulase type enzymes (eg Jewell et al, 1986).Whilst in vitro methods appear to be useful predictors of digestibility in straws, they are slow and relatively expensive. The work reported here has compared their predictive power with that of near infra-red reflectance spectroscopy (NIR).A total of 123 cereal straws were used. These included 54 wheat, 43 barley and 4 oat straws all untreated and the 9 wheat, 9 barley and 4 oat straws oven-treated with ammonia previously described by Mason et al (1988).

Analysis of antidepressant properties of some Papaver species by in vivo and in vitro methods

Planta Medica ◽  
2015 ◽  
Vol 81 (16) ◽  
Author(s):  
OML Bayazeid ◽  
F Yalcin ◽  
M İlhan ◽  
H Karahan ◽  
E Kupeli-Akkol ◽  
...  
Keyword(s):  
In Vitro Methods

The Effects of Some Synthetic Compounds on In Vitro Fibrinolytic Activity Measured by Different Methods and the Relevance to Activity In Vivo

1972 ◽  
Vol 28 (03) ◽  
pp. 351-358
Author(s):  
A.J Baillie ◽  
A. K Sim
Keyword(s):  
Inhibitory Activity ◽  
Substrate Concentration ◽  
Fibrinolytic Activity ◽  
Synthetic Compounds ◽  
In Vitro Methods ◽  
Narrow Concentration Range

SummaryThe activity of several synthetic compounds, rated from good to poor (or inactive) fibrinolytic activators, has been assessed by two different commonly-used in vitro methods. Compounds shown to be active over a narrow concentration range in the hanging clot test were shown to be inhibitors of plasmin and trypsin in the casein-olytic test. The inhibitory activity of these compounds was shown to increase with increasing substrate concentration and apparent activity in the hanging clot test. Possible explanations and relevance of these observations are discussed.

In Vitro Toxicology Methods in Risk Assessment

1996 ◽  
Vol 24 (3) ◽  
pp. 325-331
Author(s):  
Iain F. H. Purchase
Keyword(s):  
Risk Assessment ◽  
Hazard Assessment ◽  
Human Health Risk ◽  
In Vitro Test ◽  
In Vitro Methods ◽  
New Concepts ◽  
Vitro Test

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.

Studies of Metabolism Mediated Mutagenicity In Vitro

1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 243-250
Author(s):  
Dag Jenssen ◽  
Lennart Romert
Keyword(s):  
Cell Lines ◽  
Biological Effects ◽  
Animal Experiments ◽  
Culture Technique ◽  
Organ Perfusion ◽  
Isolated Cells ◽  
Toxicological Effect ◽  
In Vitro Methods

To understand the cause of the biological effects of xenobiotic metabolism in mammals, investigators have traditionally performed animal experiments by comparing the results of biochemical methods, such as measurement of enzyme activity analysis of the metabolites produced, with the observed toxicological effect. This article deals with in vitro methods for genotoxicity combined with drug metabolising preparations at the organelle, cell or organ levels, as exemplified by microsome preparations, isolated cells/cell lines and organ perfusion systems, respectively. The advantage of some of these methods for studying metabolism-mediated mutagenicity is that the measured endpoint reflects not only the bioactivating phase I reactions, but also the detoxifying phase II reactions, and the transfer of the non-conjugated reactive metabolites to other cells and their ability to cause mutations in these cells. In vivo, all these events are important factors in the initiation of cancer. A mechanistic advantage of the methods for metabolism-mediated mutagenicity in vitro is that the relevance of the different steps in metabolism for the mutational events can seldom be investigated in an in vivo assay. Furthermore, human studies can easily be performed using the co-culture technique with isolated human cells or cell lines.

The prediction of digestibility by rumen fluid and enzymatic methods

1996 ◽  
Vol 1996 ◽  
pp. 211-211
Author(s):  
Peter Young ◽  
F. P. O'Mara ◽  
M. Rath ◽  
P. J. Caffrey
Keyword(s):  
Organic Matter ◽  
Rumen Fluid ◽  
Organic Matter Digestibility ◽  
Enzymatic Methods

Rumen fluid and cellulase based techniques are widely used to predict the digestibility of compound feeds and their ingredients. Recently gammanase enzymes have been added to some cellulase based techniques (Dowman, 1993; De Boever et al., 1994). Few comparisons of these techniques have involved by-product concentrate ingredients. The objective of this experiment was to compare the ability of three techniques, in vitro rumen fluid (RF), pepsin cellulase gammanase (PCG), and neutral detergent cellulase gammanase (NCDG), to predict the in vivo organic matter digestibility (OMD) of concentrate ingredients.

Identification of Skin Irritants and Allergens by In Vivo and In Vitro Methods

2019 ◽  
pp. 1561-1577
Author(s):  
Rasika Reddy ◽  
Howard I. Maibach ◽  
Viswanath Reddy Belum ◽  
Geetanjali Sethi ◽  
Philip Hewitt
Keyword(s):  
In Vitro Methods ◽  
Skin Irritants
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