The potential digestibility of cellulose in grasses and its relationship with chemical and anatomical parameters

1972 ◽  
Vol 78 (3) ◽  
pp. 457-464 ◽  
Author(s):  
R. J. Wilkins
Keyword(s):  
Floral Development ◽  
Lignin Content ◽  
Leaf Sheath ◽  
Vascular Bundles ◽  
Cellulose Digestibility ◽  
Wimmera Ryegrass ◽  
Rate Of Decline ◽  
The Relationship ◽  
Anatomical Parameters

SUMMARYPotential cellulose digestibility, measured by incubation in vitrofor 6 days, decreased during floral development in perennial ryegrass, Wimmera ryegrass, cocksfoot, oat and tall fescue. The rate of decline was slower than for cellulose digestibility measured after incubation in vitro for 2 days only. Morphological fractions ranked in order of descending potential cellulose digestibility – leaf blade, inflorescence, leaf sheath and stem.Lignin content was determined chemically by the method of Van Soest (1963) and lignified tissue was assessed by staining transverse sections of leaf blades and leaf sheaths with safranin and fast green. Both lignin and lignified tissue increased with maturity. Lignified tissue increased mainly through increase in the number of scleren-chyma cells, but was also affected by the formation of lacunae or cavities between the vascular bundles in leaf blades of cocksfoot and in leaf sheaths of all species studied. For 19 samples of leaf blades and leaf sheaths, potential cellulose digestibility had significant negative correlations with both lignin content (r = -0·862) and lignified tissue (r = -0·905). Limitations to the techniques used to assess lignification and further factors which may affect the relationship between lignification and potential cellulose digestibility are discussed.

Physical structure of twelve forage species in relation to rate of intake by sheep

1996 ◽  
Vol 126 (3) ◽  
pp. 277-285 ◽  
Author(s):  
D. Wilman ◽  
E. J. Mtengeti ◽  
G. Moseley
Keyword(s):  
Festuca Arundinacea ◽  
Leaf Sheath ◽  
Physical Structure ◽  
Vascular Bundles ◽  
Tropical Grasses ◽  
Neutral Detergent Fibre ◽  
Parallel Lines ◽  
Chloris Gayana ◽  
The Relationship

SUMMARYIn order to understand better the relationship between plant physical structure and rate of intake, twelve plant species were compared: Trifolium repens L., Medicago sativa L., Onobrychis viciifolia Scop., Desmodium intortum (Mill.) Urb., Brassica napus L., Spergula arvensis L., Lolium perenne L., Lolium multifiorum Lam., Festuca arundinacea Schreb., Chloris gayana Kunth, Cenchrus ciliaris L. and Zea mays L. The effects of early as opposed to late harvesting were compared. Plants were grown in a heated glasshouse in each of 2 years, examined for morphology, anatomy, neutral detergent fibre and digestibility, and fed to sheep for 1-min test periods to record rate of intake.Rate of intake was in the order tropical grasses < temperate grasses < broad-leaved species < S. arvensis. The range was wide: from 4·6 g dry matter/min with C. gayana to 15·6 g with S. arvensis. The lowest rate of intake was associated with the possession of a large number of veins, close together, in parallel lines (tropical grasses); a rather higher rate was associated with fewer veins, further apart, in parallel lines (temperate grasses); the next to the highest rate was associated with broad leaves, which had a network of veins; the highest rate was associated with thin stems containing thin vascular bundles. L. perenne, L. multifiorum, C. gayana and C. ciliaris were similar in the thickness of large and small leaf blade veins and leaf sheath veins. F. arundinacea and Z. mays had rather thicker veins. T. repens, 0. viciifolia. D. intortum and B. napus were similar in the thickness of petiole vascular bundles. Neutral detergent fibre was lowest in B. napus and highest in C. gayana and C. ciliaris. In vitro digestibility was highest in B. napus and lowest in D. intortum.

COMPARISON OF GRAIN YIELD AND WHOLE-PLANT SILAGE PRODUCTION OF RECOMMENDED CORN HYBRIDS

1983 ◽  
Vol 63 (3) ◽  
pp. 601-609 ◽  
Author(s):  
M. R. VATTIKONDA ◽  
R. B. HUNTER
Keyword(s):  
Grain Yield ◽  
Dry Matter ◽  
Lignin Content ◽  
Quality Parameters ◽  
Matter Content ◽  
Dry Matter Content ◽  
Whole Plant ◽  
Silage Production ◽  
The Relationship

A 2-yr study was conducted at Elora and Brucefield, Ont. to examine the relationship between grain yield following grain physiological maturity and whole-plant dry matter (DM) yield and quality determined at the stage desirable for ensiling. Quality parameters analyzed include in vitro dry matter digestibility (IVD) of the stover, IVD of the whole plant, stover lignin content and stover protein content. There was a significant linear relationship between the performance of hybrids for grain yield production and their yield for silage production. However, the relationship was not complete enough to permit reliable selection of hybrids for silage production based on grain yield performance (coefficients of determination were 0.23 and 0.25 for Elora and Brucefield, respectively). Grain dry matter content, however, provided a satisfactory estimate of whole-plant maturity for silage production. Coefficients of determination between grain DM content and whole-plant DM content were 0.71 and 0.53 for Elora and Brucefield, respectively. There was considerable variation among hybrids for lignin content and IVD of stover. Differences were much less for whole-plant IVD. The findings of this study support the need for separate evaluation trials for corn grown for whole-plant silage production as opposed to grain production.Key words: Zea mays, corn silage, grain yield, hybrid performance

Relations entre hypolignification et état vitreux chez Salix babylonica en culture in vitro. Rôle de la nutrition ammoniacale

1985 ◽  
Vol 63 (2) ◽  
pp. 324-326 ◽  
Author(s):  
F. Daguin ◽  
R. Letouze
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Lignin Content ◽  
Nitrogen Supply ◽  
Xylem Tissue ◽  
Basal Media ◽  
Salix Babylonica ◽  
The Relationship ◽  
Different Levels

The relationship between nitrogen-fed willow cuttings cultured in vitro and the appearance of vitreous plants has been studied. By using two basal media (Murashige and Skoog medium and Knop medium half diluted) an in vitro culture scheme has been developed which allows the control of the vitrification process by varying the nitrogen supply in the culture media. The results obtained agree that the vitrification of the cloned plants is directly associated with the ammonium content of the culture medium. In vitrified plants, lignin content of the shoot is reduced by 50%. Correlatively, histological controls at different levels of the shoot of the plantlets show that the reduction of the xylem tissue can reach 70%.

The potential digestibility of cellulose in forage and faeces

1969 ◽  
Vol 73 (1) ◽  
pp. 57-64 ◽  
Author(s):  
B. J. Wilkins
Keyword(s):  
Limiting Factors ◽  
Maximum Value ◽  
Cellulose Digestibility ◽  
The Difference ◽  
The Relationship

SUMMARYThe potential digestibility of cellulose is defined as the maximum digestibility obtainable when the conditions and duration of digestion are not limiting factors. Techniques for measuring potential cellulose digestibility were examined and the relationship between potential cellulose digestibility and in vivo cellulose digestibility was explored for a range of grasses.Cellulose digestibility was found to reach a maximum value after 5 days incubation in vitro. No further cellulose was digested when the residues from an initial incubation for 6 days were incubated with a second rumen liquor inoculum. The values measured after a single incubation of 6 days duration were similar to cellulose digestibility coefficients measured by the suspension of ground forage samples in nylon bags in the rumen for 6 days. Plant factors appear to limit further digestion and the residue from prolonged digestion in vitro consisted only of lignified and cutinized tissue. Potential cellulose digestibility measured by either of the above techniques was higher than cellulose digestibility in vivo. The difference varied between forages and when the difference was large, the digestibility of cellulose in faeces was high.It is suggested that measurements of the potential digestibility of cellulose in feed and faeces may be of use in estimating the digestibility of grazed herbage.

Ultrastructural Correlations between Clonal Human Tumor Colonies and in Vivo Neoplasms

1982 ◽  
Vol 40 ◽  
pp. 210-211
Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman
Keyword(s):  
Cultured Cells ◽  
Human Tumor ◽  
Cell Type ◽  
Tumor Mass ◽  
Initial Cell ◽  
Cloning Assay ◽  
Human Tumor Cloning ◽  
The Relationship

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.

Plasminogen Depletion during Streptokinase Treatment or Two-Chain Urokinase Incubation Correlates with Decreased Clot Lysability Ex Vivo and In Vitro

1993 ◽  
Vol 70 (06) ◽  
pp. 0998-1004 ◽  
Author(s):  
Páll T Önundarson ◽  
H Magnús Haraldsson ◽  
Lena Bergmann ◽  
Charles W Francis ◽  
Victor J Marder
Keyword(s):  
Myocardial Infarction ◽  
Ex Vivo ◽  
Time Dependent ◽  
State Variables ◽  
Thrombolytic Treatment ◽  
Direct Proportion ◽  
Plasmin Activity ◽  
Plasma Exposure ◽  
The Relationship

SummaryThe relationship between lytic state variables and ex vivo clot lysability was investigated in blood drawn from patients during streptokinase administration for acute myocardial infarction. A lytic state was already evident after 5 min of treatment and after 20 min the plasminogen concentration had decreased to 24%, antiplasmin to 7% and fibrinogen 0.2 g/1. Lysis of radiolabeled retracted clots in the patient plasmas decreased from 37 ± 8% after 5 min to 21 ± 8% at 10 min and was significantly lower (8 ± 9%, p <0.005) in samples drawn at 20, 40 and 80 min. Clot lysability correlated positively with the plasminogen concentration (r = 0.78, p = 0.003), but not with plasmin activity. Suspension of radiolabeled clots in normal plasma pre-exposed to 250 U/ml two-chain urokinase for varying time to induce an in vitro lytic state was also associated with decreasing clot lysability in direct proportion with the duration of prior plasma exposure to urokinase. The decreased lysability correlated with the time-dependent reduction in plasminogen concentration (r = 0.88, p <0.0005). Thus, clot lysability decreases in conjunction with the development of the lytic state and the associated plasminogen depletion. The lytic state may therefore limit reperfusion during thrombolytic treatment.

Monitoring Anticoagulant Therapy by Activated Partial Thromboplastin Time: Hirudin Assessment

1994 ◽  
Vol 72 (05) ◽  
pp. 685-692 ◽  
Author(s):  
Michael T Nurmohamed ◽  
René J Berckmans ◽  
Willy M Morriën-Salomons ◽  
Fenny Berends ◽  
Daan W Hommes ◽  
...  
Keyword(s):  
Whole Blood ◽  
Partial Thromboplastin Time ◽  
Ex Vivo ◽  
Fold Increase ◽  
Heparin Therapy ◽  
Activated Partial Thromboplastin Time ◽  
Recombinant Hirudin ◽  
Interindividual Differences ◽  
The Relationship

SummaryBackground. Recombinant hirudin (RH) is a new anticoagulant for prophylaxis and treatment of venous and arterial thrombosis. To which extent the activated partial thromboplastin time (APTT) is suitable for monitoring of RH has not been properly evaluated. Recently, a capillary whole blood device was developed for bed-side monitoring of the APTT and it was demonstrated that this device was suitable to monitor heparin therapy. However, monitoring of RH was not evaluated.Study Objectives. To evaluate in vitro and ex vivo the responsiveness and reproducibility for hirudin monitoring of the whole blood monitor and of plasma APTT assays, which were performed with several reagents and two conventional coagulometers.Results. Large interindividual differences in hirudin responsiveness were noted in both the in vitro and the ex vivo experiments. The relationship between the APTT, expressed as clotting time or ratio of initial and prolonged APTT, and the hirudin concentration was nonlinear. A 1.5-fold increase of the clotting times was obtained at 150-200 ng/ml plasma. However, only a 2-fold increase was obtained at hirudin levels varying from 300 ng to more than 750 ng RH/ml plasma regardless of the assays. The relationship linearized upon logarithmic conversion of the ratio and the hirudin concentration. Disregarding the interindividual differences, and presuming full linearity of the relationship, all combinations were equally responsive to hirudin.Conclusions. All assays were equally responsive to hirudin. Levels up to 300 ng/ml plasma can be reliably estimated with each assay. The manual device may be preferable in situations where rapid availability of test results is necessary.

Thickness of endometrium: predictor of the effectiveness of IVF/ICSI programs (literature review)

GYNECOLOGY ◽  
2018 ◽  
Vol 20 (1) ◽  
pp. 113-116
Author(s):  
L A Bagdasaryan ◽  
I E Korneyeva
Keyword(s):  
Assisted Reproductive Technologies ◽  
Endometrial Thickness ◽  
Molecular Genetic ◽  
Uterine Cavity ◽  
Reproductive Technologies ◽  
Genetic Characteristics ◽  
Vitro Fertilization ◽  
Need To Evaluate ◽  
The Relationship

The aim of the study is to systematically analyze the data available in the modern literature on the relationship between endometrial thickness and the frequency of pregnancy in the program of assisted reproductive technologies (ART). Materials and methods. The review includes data from foreign and domestic articles found in PubMed on this topic. Results. The article presents data on the relationship between the thickness of the endometrium and the frequency of pregnancy in ART programs. The greatest number of studies is devoted to the evaluation of the relationship between the thickness of the endometrium and the frequency of pregnancy on the day of the ovulation trigger. Data are presented on the existence of a correlation between the thickness of the endometrium measured on the day of the ovulation trigger and the frequency of clinical pregnancy, as well as data on the need to evaluate the structure of the endometrium and the state of subendometric blood flow. The importance of multilayered (three-layered) endometrium as a prognostic marker of success in in vitro fertilization/intracytoplasmic sperm injection programs in the ovum is emphasized. The conclusion. The thickness of the endometrium can not be used as an argument for canceling the cycle or abolishing embryo transfer to the uterine cavity. Further studies in this direction are needed with a study of the morphological and molecular genetic characteristics of the endometrium, which in the future will allow us to evaluate the relationship between the thickness of the endometrium and the probability of pregnancy.

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