ISOALDEHYDEDIUREAS AS NONPROTEIN NITROGEN SOURCES FOR RUMINANT ANIMALS

1989 ◽  
Vol 69 (4) ◽  
pp. 989-998
Author(s):  
MARINA A. G. VON KEYSERLINGK ◽  
G. W. MATHISON
Keyword(s):  
Experimental Design ◽  
Incubation Medium ◽  
Rumen Fluid ◽  
Nitrogen Sources ◽  
Isovaleric Acid ◽  
Nonprotein Nitrogen ◽  
Degradation Rates ◽  
Ruminant Animals

In experiments designed to evaluate isovaleridenediurea (IVDU; butanal, 3-methyl-di-urea) as a nonprotein nitrogen supplement for ruminant animals IVDU and isobutylidenediurea (IBDU; propanal, 2-methyl-di-urea) were compared to urea. Ammonia concentrations were increased (P < 0.05) by 2–5 mM when IBDU or IVDU were added to an in vitro incubation medium in comparison with up to 24 mM when equal amount of urea nitrogen was used. Isobutyric and isovaleric acid concentrations in the incubation medium were higher (P < 0.05) when IBDU and IVDU, respectively, were present. In an in vivo experiment, ammonia concentrations were reduced (P < 0.05) from 7.0 to 4.7 mM at 0.5 h after feeding when a mixture of 6 g IBDU and 6 g IVDU was substituted for 6.8 g urea in the diet of four sheep fed 1200 g hay and 100 g concentrate daily in a crossover experimental design. No differences (P > 0.05) in isobutyric or isovaleric acid concentrations in the rumen fluid were observed between treatments. Apparent digestibilities were not influenced by diet. It was concluded that although IVDU and IBDU had potential as nonprotein nitrogen supplements, degradation rates of both compounds were low and excessive amounts of the compounds may escape from the rumen undegraded. Key words: Sheep, isobutylidenediurea, isovaleridenediurea, nonprotein nitrogen supplements, in vitro, in vivo

IN VITRO UPTAKE OF TRITIATED OESTRADIOL BY THE ANTERIOR HYPOTHALAMUS AND HYPOPHYSIS OF THE RAT

1970 ◽  
Vol 64 (4) ◽  
pp. 687-695 ◽  
Author(s):  
Junzo Kato
Keyword(s):  
Incubation Medium ◽  
Posterior Hypothalamus ◽  
Anterior Hypothalamus ◽  
Ovariectomized Rats ◽  
Free Medium ◽  
Cortex Cerebri ◽  
Anterior Hypophysis ◽  
In Vitro Uptake

ABSTRACT The anterior, middle, and posterior hypothalamus, the cortex cerebri, the anterior hypophysis as well as the diaphragm of adult ovariectomized rats were incubated in vitro with tritiated 17β-oestradiol. The uptake of tritiated oestradiol was differentially distributed intracerebrally with higher accumulation in the anterior hypothalamus and the hypophysis. Lowering the temperature of the incubation medium caused a reduction in the uptake of radioactivity by the anterior hypothalamus as compared to that found in other brain tissues. Tritiated oestradiol taken up in vitro by the anterior hypothalamus and the hypophysis tended to be retained after further incubation in a steroid-free medium. The addition of non-radioactive 17β-oestradiol to the medium inhibited the uptake of tritiated oestradiol by these tissues. Moreover, pretreatment with non-radioactive 17β-oestradiol in vivo prevented the preferential accumulation of tritiated oestradiol in vitro in the anterior hypothalamus and the hypophysis. These results indicate that oestradiol is preferentially taken up in vitro by the anterior hypothalamus and the hypophysis of the rat.

scholarly journals The Effects of Conjugated Linoleic Acids on Cancer

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 454 ◽  
Author(s):  
Marko Dachev ◽  
Jana Bryndová ◽  
Milan Jakubek ◽  
Zdeněk Moučka ◽  
Marian Urban
Keyword(s):  
Potential Effect ◽  
Conjugated Linoleic Acids ◽  
Carcinogenic Activity ◽  
Beneficial Effects ◽  
True Value ◽  
Ruminant Animals ◽  
Anti Oxidant ◽  
Cancer Agent

Conjugated linoleic acids (CLA) are distinctive polyunsaturated fatty acids. They are present in food produced by ruminant animals and they are accumulated in seeds of certain plants. These naturally occurring substances have demonstrated to have anti-carcinogenic activity. Their potential effect to inhibit cancer has been shown in vivo and in vitro studies. In this review, we present the multiple effects of CLA isomers on cancer development such as anti-tumor efficiency, anti-mutagenic and anti-oxidant activity. Although the majority of the studies in vivo and in vitro summarized in this review have demonstrated beneficial effects of CLA on the proliferation and apoptosis of tumor cells, further experimental work is needed to estimate the true value of CLA as a real anti-cancer agent.

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.

scholarly journals Digestion of timothy silage and hay in reindeer

Rangifer ◽  
1998 ◽  
Vol 18 (1) ◽  
pp. 35
Author(s):  
R. Moen ◽  
M. A. Olsen ◽  
Ø. E. Haga ◽  
W. Sørmo ◽  
T. H. Aagnes Utsi ◽  
...  
Keyword(s):  
Food Intake ◽  
Rangifer Tarandus ◽  
Rumen Fluid ◽  
Total Concentration ◽  
Phleum Pratense ◽  
Water Soluble ◽  
Soluble Carbohydrates ◽  
Energy Deficiency

Leafy timothy (Phleum pratense) silage (S), silage mixed with molasses (SM) and hay (H) were fed to nine male reindeer (Rangifer tarandus tarandus) calves in winter to investigate rumen function and digestion. Three calves were given S with 18.5% dry matter (DM), three were given SM (21.9% DM) and three were given H (85.0% DM). The content of water soluble carbohydrates (in % of DM) was 8.2% in S, 16.0% in SM and 8.5% in H. Median (range) daily DM food intake per kg BM was 12.9 (9-2-14.4) g in calves fed S, 19.0 (19-0-21.9) g in calves fed SM and 21.0 (19.2&not;21.1) g in calves fed H. In vivo digestion of S and SM DM ranged from 78.5-83.1% compared to only 69-9-72.9% in calves fed H. In vitro DM digestion (IVDMD) of cellulose (median) incubated for 48 hours in rumen fluid was, however, significantly (F = 0.05) lower in calves fed S (24.4%) compared to calves fed SM (42.2%). Median IVDMD of cellulose (48 hours) in calves fed H was 36.4%. Total concentration of VFA (range) in the rumen fluid from reindeer fed H (99.7-113.6 mM) and was significantly (P&lt;0.05) higher compared to animals fed S (57.7-85.9 mM) or SM (51.4-72.0 mM). Likewise, the pH of the rumen fluid (range) was significantly (P&lt;0.05) lower in reindeer fed H (6.40-6.78) compared to animals fed S (6.97-7.30) or SM (6.79-7.27). Based on this study it is concluded that leafy timothy preserved as hay seems to be more suitable as emergency feed compared to silage. Supplementation of molasses to silage seems to stimulate food intake and ruminal cellulose digestion in reindeer. The lower intake of S compared to SM or H by reindeer may be explained by ruminal energy deficiency.

scholarly journals Microstructure and Mechanical Properties of PU/PLDL Sponges Intended for Grafting Injured Spinal Cord

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2693
Author(s):  
Anna Lis-Bartos ◽  
Dariusz Szarek ◽  
Małgorzata Krok-Borkowicz ◽  
Krzysztof Marycz ◽  
Włodzimierz Jarmundowicz ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Spinal Cord ◽  
Young Modulus ◽  
In Vivo Studies ◽  
Polymer Composition ◽  
In Vitro Toxicity ◽  
Injured Spinal Cord ◽  
Degradation Rates

Highly porous, elastic, and degradable polyurethane and polyurethane/polylactide (PU/PLDL) sponges, in various shapes and sizes, with open interconnected pores, and porosity up to 90% have been manufactured. They have been intended for gap filling in the injured spinal cord. The porosity of the sponges depended on the content of polylactide, i.e., it decreased with the increase of polylactide content. The rise of polylactide content caused an increase of Young modulus and rigidity as well as a more complex morphology of the polyurethane/polylactide blends. The mechanical properties, in vitro toxicity, and degradation in artificial cerebrospinal fluid were tested. Sponges underwent continuous degradation with varying degradation rates depending on the polymer composition. In vitro cell studies with fibroblast cultures proved the biocompatibility of the polymers. Based on the obtained results, the designed PU/PLDL sponges appeared to be promising candidates for bridging gaps within injured spinal cord in further in vitro and in vivo studies.

EFFECTS OF HYDROXYSTEROID DEHYDROGENASE INHIBITORS ON IN-VITRO AND IN-VIVO STEROIDOGENESIS IN THE OVINE ADRENAL GLAND

1982 ◽  
Vol 92 (2) ◽  
pp. 205-212 ◽  
Author(s):  
P. SINGH-ASA ◽  
G. JENKIN ◽  
G. D. THORBURN
Keyword(s):  
Adrenal Gland ◽  
Incubation Medium ◽  
Bovine Serum ◽  
Hydroxysteroid Dehydrogenase ◽  
Inhibitory Effect ◽  
Bovine Serum Albu ◽  
Stimulatory Action ◽  
Adrenal Steroidogenesis

The effectiveness of trilostane and azastene as inhibitors of adrenal steroidogenesis was compared by in-vitro and in-vivo methods. A radioimmunoassay was developed for the measurement of cortisol in ovine plasma, incubation medium and tissue extract using a specific antiserum raised against cortisol 21-acetate,3-carboxymethyloxime : bovine serum albu Trilostane (20 μmol/l) decreased cortisol synthesis and release both in unstimulated and in ACTH-stimulated adrenal tissues in vitro. The same concentration of azastene had a lesser effect on unstimulated adrenals and was completely ineffective in blocking the stimulatory action of ACTH. In vivo, trilostane suppressed adrenal steroidogenesis in pregnant and cyclic ewes but the suppression in pregnant ewes was over a longer period, and after lower doses. It is concluded that trilostane had an inhibitory effect on ovine adrenal steroidogenesis both in vitro and in vivo.

Natural Poly(Hydroxybutyrate-Hydroxyvalerate) Polymers as Degradable Biomatertals.

1995 ◽  
Vol 394 ◽  
Author(s):  
Cyril Chaput ◽  
L'Hocine Yahia ◽  
Amine Selmani ◽  
Charles-Hilaire Rivard
Keyword(s):  
Copolymer Composition ◽  
Inflammatory Reactions ◽  
Accelerated Degradation ◽  
Physico Chemical ◽  
Degradation Rates ◽  
Degradable Biomaterials ◽  
Tissue Reactions ◽  
Toxic Responses

AbstractPoly(ß-hydroxybutyrate-co-13-hydroxyvalerate) have been recently proposed as degradable biomaterials for drug delivery systems, sutures, bone plates and short-term implants. Three P-B\HV (7, 14 & 22 % HV) films were analyzed for in vitro cytotoxicity and aqueous accelerated degradation, in vivo degradation and tissue reactions. The PHB/HV materials and extracts elicit few or mild toxic responses, do not lead in vivo to tissue necrosis or abscess formation, but provoke acute inflammatory reactions slightly decreasing with the time. The degradation of PHB/HV polymers present low rates in vitro as well as in vivo. The weight loss rate generally increases with the copolymer composition (HV content) and ranges from 0.15- 0.30 (in vitro) to 0.25 %/day (in vivo). Compositional and physico-chemical changes in PHB/HV materials were rapidly detected during the accelerated hydrolysis, but were much slower to appear in vivo. The structural and mechanical integrity of PHB/HV materials tend to disappear early in vitro as well as in vivo. After 90 wks in dorsal muscular tissues of adult sheep, there was no significant dissolution of the PHB/HV polymer, 50–60% of the initial weight still remaining. PHB/HV polymers are biodegradable materials, either by hydrolysis or implantation, but with extremely low dissolution or degradation rates.

Differences between the in vitro digestibility of extrusa collected from oesophageal fistulated steers and the forage consumed

2009 ◽  
Vol 49 (7) ◽  
pp. 563 ◽  
Author(s):  
David B. Coates ◽  
Robert J. Mayer
Keyword(s):  
Dry Matter ◽  
Rumen Fluid ◽  
In Vitro Digestibility ◽  
In Vitro Techniques ◽  
Pasture Legumes ◽  
Dry Matter Digestibility ◽  
Significant Difference ◽  
C3 Grasses

In a study that included C4 tropical grasses, C3 temperate grasses and C3 pasture legumes, in vitro dry matter digestibility of extrusa, measured as in vitro dry matter loss (IVDML) during incubation, compared with that of the forage consumed, was greater for grass extrusa but not for legume extrusa. The increase in digestibility was not caused by mastication or by the freezing of extrusa samples during storage but by the action of saliva. Comparable increases in IVDML were achieved merely by mixing bovine saliva with ground forage samples. Differences were greater than could be explained by increases due to completely digestible salivary DM. There was no significant difference between animals in relation to the saliva effect on IVDML and, except for some minor differences, similar saliva effects on IVDML were measured using either the pepsin–cellulase or rumen fluid–pepsin in vitro techniques. For both C4 and C3 grasses the magnitude of the differences were inversely related to IVDML of the feed and there was little or no difference between extrusa and feed at high digestibilities (>70%) whereas differences of more than 10 percentage units were measured on low quality grass forages. The data did not suggest that the extrusa or saliva effect on digestibility was different for C3 grasses than for C4 grasses but data on C3 grasses were limited to few species and to high digestibility samples. For legume forages there was no saliva effect when the pepsin–cellulase method was used but there was a small but significant positive effect using the rumen fluid–pepsin method. It was concluded that when samples of extrusa are analysed using in vitro techniques, predicted in vivo digestibility of the feed consumed will often be overestimated, especially for low quality grass diets. The implications of overestimating in vivo digestibility and suggestions for overcoming such errors are discussed.

Refined experimental design may increase the value of murine models for estimation of bluetongue virus virulence

2020 ◽  
pp. 002367722093005
Author(s):  
Maria Stokstad ◽  
Peter Coetzee ◽  
Mette Myrmel ◽  
Paidamwoyo Mutowembwa ◽  
Estelle H Venter ◽  
...  
Keyword(s):  
Experimental Design ◽  
Response Surface ◽  
Bluetongue Virus ◽  
Reverse Genetics ◽  
Lethal Dose ◽  
Murine Models ◽  
Negative Consequences ◽  
Infectious Dose

Bluetongue is a serious non-contagious vector-borne viral disease in ruminants, causing poor animal welfare and economic consequences globally. Concern has been raised about the development of novel bluetongue virus (BTV) strains and their possibly altered virulence through the process of viral reassortment. Virulence is traditionally estimated in lethal dose 50 (LD50) studies in murine models, but agreement with both in vitro and virulence in ruminants is questionable, and a refined experimental design is needed. Specific reassortants between wild-type and vaccine strains of BTV-1, -6 and -8 have previously been developed by reverse genetics. The aim of the present study was to rank the in vivo virulence of these parental and reassortant BTV strains by calculating LD50 in a murine model by using an experimental design that is new to virology: a between-patient optimised three-level response surface pathway design. The inoculation procedure was intracranial. Fifteen suckling mice were used to establish LD50 for each strain. Three parental and five reassortant virus strains were included. The LD50s varied from of 0.1 (95% confidence interval (CI) 0–0.20) to 3.3 (95% CI 2.96–3.72) tissue culture infectious dose 50/ml. The results support the hypothesis that reassortment in BTV may lead to increased virulence in mice with potential negative consequences for the natural ruminant host. The ranking showed low agreement with in vitro properties and virulence in ruminants according to existing literature. Refined design such as response surface pathway design was found suitable for use in virology, and it introduces significant ethical and scientific improvements.

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