scholarly journals  Use of the mobile nylon bag technique for determination of apparent ileal digestibilities of crude protein and amino acids in feedstuffs for pigs

2011 ◽  
Vol 56 (No. 10) ◽  
pp. 451-464 ◽  
Author(s):  
T. Steiner ◽  
U. Bornholdt ◽  
W.C. Sauer ◽  
F. Ahrens ◽  
H. Jørgensen ◽  
...  

Three digestibility experiments were conducted to evaluate the potential of determination of apparent ileal digestibilities (AID) of crude protein (CP) and amino acids (AA) by the mobile nylon bag technique (MNBT) using 21 feedstuffs and three mixed diets. In two conventional digestibility experiments (Exp. 1 and 2), AID were determined using in total 10 barrows (BW 35 kg) fitted with simple T-cannulas at the terminal ileum. For the MNBT studies, four pigs were fitted with a simple T-cannula at the proximal duodenum and a Post-Valve T-Caecum (PVTC) cannula at the terminal ileum. The MNBT studies included the feedstuffs (n = 10) from Exp. 1 and 2 as well as 14 further feedstuffs and mixed diets in which AID coefficients had been determined in previous trials. For each feedstuff 60 nylon bags were used. In vitro digestion of the bags was carried out in pepsin-HCl solution with 450 IU pepsin/l at pH 2.0 and 37°C for 4 h. In the 28-day in vivo experiment, 15 nylon bags per pig and day were inserted through the duodenal cannula and collected through the PVTC cannula after passage through the small intestine. Coefficients of AID were calculated based on the disappearance of CP and AA from the nylon bags during the in vitro and in vivo phase. In comparison with AID determined by the conventional method, AID of CP was on average 2.4% lower, whereas AID of lysine was on average 8.5% higher when determined by the MNBT. There was no significant (P > 0.05) correlation between AID coefficients of CP and AA determined by the conventional method and the MNBT, when all feedstuffs were taken into account. However, in cereals (n = 11), the correlation between AID coefficients determined by both methods was significant (P < 0.05) for CP (r = 0.61) and some AA (r ranging between 0.62 and 0.72). In conclusion, the potential of the MNBT to determine AID of CP and AA is rather limited. Differences in coefficients of AID of CP and AA were attributed to several factors such as diffusion of sample particles or endogenous protein through the nylon bags as well as to the presence of anti-nutritional factors (e.g. in legume seeds and oilseed meals).

2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4507
Author(s):  
Luiz Juliano Valério Geron ◽  
Fabiana Gomes da Costa ◽  
Silvia Cristina de Aguiar ◽  
Jocilaine Garcia ◽  
Matheus Gonçalves Ribeiro ◽  
...  

<p>This study evaluated the digestibility of nutrients by, and parameters associated with, <em>in vitro </em>fermentation using different inocula (sheep ruminal fluid and feces) as well as the <em>in vivo </em>digestibility in sheep that were fed rations with 50% concentrate containing either no (0%) residue from the extraction of tamarind pulp (RETP) or 15% RETP. To determine the <em>in vitro </em>digestibility (<em>IV</em>D) of nutrients, two sheep, weighing 40.38 ± 2.10 kg, were used as inoculum donors. To determine the <em>in vivo </em>digestibility of nutrients, we used four sheep and a 3×2 factorial experimental design, with three methods of digestion of nutrients and two experimental rations (0% and 15% RETP). The variables were subjected to analysis of variance and the variables that showed differences at 5% probability were further analyzed using the Tukey test at 5% significance. The <em>IV</em>D using different inocula did not significantly differ (p&gt;0.05) from the <em>in vivo </em>digestibility in sheep for dry matter (DM), organic matter (OM), and neutral detergent fiber (NDF). The different methods for determining nutrient digestibility did not affect (p&gt;0.05) the digestibility of DM, OM, crude protein (CP), NDF, and acid detergent fiber (ADF) in rations with 0% and 15% RETP. However, the <em>IV</em>D of CP for rations containing 0% and 15% RETP incubated with both inocula was lower (p&lt;0.05) than the CP digestibility <em>in vivo</em>. The <em>in vivo </em>digestibility of ADF for rations containing 0% and 15% RETP was higher (P&lt;0.05) than the <em>IV</em>D using sheep ruminal fluid and feces as inocula. The pH values and concentration of ammonia nitrogen (NH3-N) after <em>in vitro </em>incubation for 24 h and the <em>in vivo </em>assay were not different (p&gt;0.05) for the rations containing 0% and 15% RETP, but the pH and NH3-N of both fermented and rumen contents differed (p&lt;0.05) depending on the inocula used and the <em>in vivo </em>assay. In summary, the digestibility of DM, OM, and NDF can be determined by the <em>in vitro </em>fermentation method using the ruminal fluid or feces of sheep as inocula in rations containing 0% or 15% RETP. However, <em>in vitro </em>fermentation is not a suitable method for the determination of pH and NH3-N concentration.</p>


2004 ◽  
Vol 79 (2) ◽  
pp. 265-271 ◽  
Author(s):  
V. Ravindran ◽  
W. H. Hendriks

AbstractEndogenous flows of nitrogen and amino acids at the terminal ileum of broilers (6 weeks old), layers (70 weeks old) and adult roosters (70 weeks old) were determined using the peptide alimentation method. The ileal endogenous output of nitrogen and total amino acids in broilers, layers and roosters, expressed as mg/kg dry matter intake, were similar (F > 0-05). Endogenous flows were similar (F > 0-05) for nine of the 17 amino acids analysed, but the flows of serine, glutamic acid, proline, alanine, isoleucine, tyrosine, arginine and methionine differed (P < 0-05) among the classes of chickens. The amino acid profile of endogenous protein, expressed asg/100 g crude protein, did not differ (F > 0-05) between the three classes of chickens, except for serine, glutamic acid, proline and isoleucine. The concentrations of proline were higher (F < 0-05) in broilers, compared with the other two groups. The concentrations of glutamic acid in layers were lower (F < 0-05) than the other two groups. The concentrations of serine and isoleucine were higher (F < 0-05) in roosters than the other two groups. In all three groups, the most abundant amino acid in the ileal endogenous protein was glutamic acid, followed by aspartic acid, proline, serine, glycine and threonine. The present study provides estimates for endogenous amino acid flow at the terminal ileum in broilers, layers and adult roosters under normal physiological conditions.


2021 ◽  
Author(s):  
Yesudas Gudivada

While in vivo methods have been used to determine the glycemic response of food, they are time consuming, costly, and not suitable for large-scale applications. As an alternative, in vitro digestion models offer fast, reproducible results to study food digestion kinetics that are less expensive than conducting human trials. While there are several in vitro glycemic index (GI) methods used to determine the GI of food, most do not employ methods of in vivo testing. Therefore, we used a static in vitro digestive system, the Dedicated Ryerson University In-vitro Digester (DRUID), that simulates both gastric and intestinal conditions to determine the glycemic response of commonly consumed carbohydrate-containing foods. Samples were collected at regular intervals over a 2h residence time after digestion in the intestinal phase of the DRUID. The DRUID-determined GI values were compared to published in vivo GI values. A Bland-Altman plot showed that there was agreement between the GI values determined from the DRUID compared with published in vivo GI values. In conclusion, the in vitro DRUID can reliably and reproducibly determine the GI across a spectrum of carbohydrate-containing foods, and has the potential to predict the digestion kinetics of novel food products in vivo that may promote human health.


1970 ◽  
Vol 24 (1) ◽  
pp. 227-240 ◽  
Author(s):  
S. Elizabeth Nixon ◽  
G. E. Mawer

1. The absorption of the amino acid components of two protein-containing test meals has been studied in six healthy volunteers. One meal contained 15 g of milk protein and the other contained 15 g of gelatin. In a control experiment a meal was given which contained a negligible amount of protein.2. The subjects were intubated with a single lumen tube; then each meal was swallowed and intestinal residues were obtained from known levels. The amino acid composition of the intestinal contents was compared with that of the original meal. Correction was made for net water shifts by reference to a non-absorbable marker compound (polyethylene glycol 4000).3. The results showed that at least 70–75% of the milk protein test meal had been absorbed when the sampling holes were 230 cm from the nose. It is suggested, however, that most, if not all, of the meal had been absorbed when the sampling holes were 140 cm from the nose.4. Amino acids were absorbed at rates proportional to their concentrations in the meal.5. Gelatin, a protein known to be relatively resistant to enzymic hydrolysis, was poorly absorbed from the region of the small intestine under study.6. Estimates of the amount of endogenous protein secreted in response to the test meals ranged from z to 8 g, equivalent to 13–53% of the protein containing test meals.7. The absorption of certain amino acids, e.g. the dicarboxylic amino acids, was more rapid than was expected; glutamic and aspartic acids are absorbed slowly from a mixture of amino acids, both in vitro and in vivo.


2013 ◽  
Vol 6 (2) ◽  
pp. 167-184 ◽  
Author(s):  
C.A. González-Arias ◽  
S. Marín ◽  
V. Sanchis ◽  
A.J. Ramos

In the evaluation of the oral bioavailability of a mycotoxin, the first step is the determination of its bioaccessibility, i.e. the percentage of mycotoxin released from the food matrix during digestion in the gastrointestinal (GI) tract that could be absorbed through the intestinal epithelium. Different in vitro digestion models have been recently used for determination of bioaccessibility, thereby avoiding the use of more complex cell culture techniques or the use of animals in expensive in vivo experiments. In vitro methods offer an appealing alternative to human and animal studies. They usually are rapid, simple and reasonably low in cost, and can be used to perform simplified experiments under uniform and well-controlled conditions, providing insights not achievable in whole animal studies. The available in vitro methods for GI simulation differ in the design of the system, the composition of the physiological juices assayed, as well as in the use or not of intestinal microbiota. There are models that only simulate the upper part of the GI tract (mouth-stomach-small intestine), whereas other methods include the large intestine, so that the model chosen could have some influence on the bioaccessibility data obtained. Bioaccessibility depends on the food matrix, as well as on the contamination level and the way the food/feed is contaminated (spiked or naturally). This review focuses on the currently available data regarding in vitro digestion models for the study of the bioaccessibility or absorption of mycotoxins, detailing the characteristics of each digestion step and the importance of the physiological juices employed during digestion. The effect that different factors play on mycotoxin release from the food matrix in the GI tract is also considered, and existing data on bioaccessibility of the main mycotoxins are given.


2021 ◽  
Author(s):  
Yesudas Gudivada

While in vivo methods have been used to determine the glycemic response of food, they are time consuming, costly, and not suitable for large-scale applications. As an alternative, in vitro digestion models offer fast, reproducible results to study food digestion kinetics that are less expensive than conducting human trials. While there are several in vitro glycemic index (GI) methods used to determine the GI of food, most do not employ methods of in vivo testing. Therefore, we used a static in vitro digestive system, the Dedicated Ryerson University In-vitro Digester (DRUID), that simulates both gastric and intestinal conditions to determine the glycemic response of commonly consumed carbohydrate-containing foods. Samples were collected at regular intervals over a 2h residence time after digestion in the intestinal phase of the DRUID. The DRUID-determined GI values were compared to published in vivo GI values. A Bland-Altman plot showed that there was agreement between the GI values determined from the DRUID compared with published in vivo GI values. In conclusion, the in vitro DRUID can reliably and reproducibly determine the GI across a spectrum of carbohydrate-containing foods, and has the potential to predict the digestion kinetics of novel food products in vivo that may promote human health.


1975 ◽  
Vol 15 (75) ◽  
pp. 471 ◽  
Author(s):  
J Clark

The digestibilities of the dry matter (DDM) of 16 herbages and 22 mixtures of grain and hay of known in vivo digestibility were determined by a two-stage in vitro technique, with inocula obtained from sheep fed either hay or a diet of 70 per cent barley and 30 per cent hay; both diets contained 12 per cent crude protein. The in vitro digestions were conducted with or without the addition of ammonium sulphate. The correlations between in vivo and in vitro digestibilities were higher for the herbages and the mixtures with inoculum from sheep fed hay, than with that from sheep fed barley and hay. Adding ammonium sulphate to either inoculum lowered the in vivo-in vitro correlation for the mixtures containing grain but improved the correlation for the herbage samples. The variability between replicate in vitro determinations was not reduced by adding ammonium sulphate to the inoculum from sheep fed hay but was increased for the inoculum from sheep fed a mixture of barley and hay.


Animals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3553
Author(s):  
Geruza Silveira Machado ◽  
Ana Paula Folmer Correa ◽  
Paula Gabriela da Silva Pires ◽  
Letícia Marconatto ◽  
Adriano Brandelli ◽  
...  

Feathers are naturally made up of non-digestible proteins. Under thermal processing, total tract digestibility can be partially improved. Furthermore, Bacillus subtilis (Bs) has shown a hydrolytic effect In vitro. Then, a Bs FTC01 was selected to hydrolyze enough feathers to produce a meal, and then test the quality and inclusion in the dog’s diet to measure the apparent total tract digestibility coefficient (ATTDC) in vivo and the microorganism’s ability to survive in the gastrointestinal tract. A basal diet was added with 9.09% hydrolyzed Bs feather meal (HFMBs) or 9.09% thermally hydrolyzed feather meal (HFMT). Nine adult dogs were randomized into two 10-day blocks and fed different diets. Microbial counts were performed on feather meal, diets and feces. The Bs was less effective in digesting the feathers, which reduced the ATTDC of dry matter, crude protein, energy and increased the production of fecal DM, but the fecal score was maintained (p > 0.05). The digestible energy of HFMT and HFMBs was 18,590 J/kg and 9196 J/kg, respectively. Bacillus subtilis showed limitation to digest feather in large scale, but the resistance of Bs to digestion was observed since it grown on feces culture.


1987 ◽  
Vol 26 (01) ◽  
pp. 1-6 ◽  
Author(s):  
S. Selvaraj ◽  
M. R. Suresh ◽  
G. McLean ◽  
D. Willans ◽  
C. Turner ◽  
...  

The role of glycoconjugates in tumor cell differentiation has been well documented. We have examined the expression of the two anomers of the Thomsen-Friedenreich antigen on the surface of human, canine and murine tumor cell membranes both in vitro and in vivo. This has been accomplished through the synthesis of the disaccharide terminal residues in both a and ß configuration. Both entities were used to generate murine monoclonal antibodies which recognized the carbohydrate determinants. The determination of fine specificities of these antibodies was effected by means of cellular uptake, immunohistopathology and immunoscintigraphy. Examination of pathological specimens of human and canine tumor tissue indicated that the expressed antigen was in the β configuration. More than 89% of all human carcinomas tested expressed the antigen in the above anomeric form. The combination of synthetic antigens and monoclonal antibodies raised specifically against them provide us with invaluable tools for the study of tumor marker expression in humans and their respective animal tumor models.


1974 ◽  
Vol 32 (02/03) ◽  
pp. 405-416 ◽  
Author(s):  
M. R Hardeman ◽  
Carina J L. Heynens

SummaryStorage experiments were performed at 4°, 25° and 37° C with platelet-rich plasma under sterile conditions. In some experiments also the effect of storing platelets at 4° C in whole blood was investigated.Before, during and after three days of storage, the platelets were tested at 37° C for their serotonin uptake and response to hypotonic shock. In addition some glycolytic intermediates were determined.A fair correlation was noticed between the serotonin uptake and hypotonic shock experiments. Both parameters were best maintained at 25° C. Also platelet counting, performed after the storage period, indicated 25° C as the best storage temperature. Determination of glycolytic intermediates did not justify any conclusion regarding the optimal storage temperature. Of the various anticoagulants studied, ACD and heparin gave the best results as to the serotonin uptake and hypotonic shock response, either with fresh or stored platelets. The use of EDTA resulted in the lowest activity, especially after storage.The results of these storage experiments in vitro, correspond well with those in vivo reported in the literature.


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