Digestibility

Distribution by Scientific Domains
Distribution within Earth and Environmental Science

Kinds of Digestibility

  • apparent digestibility
  • apparent protein digestibility
  • diet digestibility
  • dm digestibility
  • dry matter digestibility
  • energy digestibility
  • enzymatic digestibility
  • lipid digestibility
  • matter digestibility
  • nutrient digestibility
  • protein digestibility
  • starch digestibility
  • total tract digestibility
  • tract digestibility
  • vitro digestibility
  • vitro dry matter digestibility
  • vitro protein digestibility

  • Terms modified by Digestibility

  • digestibility coefficient
  • digestibility experiment
  • digestibility studies
  • digestibility test
  • digestibility trial
  • digestibility value

  • Selected Abstracts


    IN VITRO DIGESTIBILITY OF CHINESE TARTARY BUCKWHEAT PROTEIN FRACTIONS: THE MICROSTRUCTURE AND MOLECULAR WEIGHT DISTRIBUTION OF THEIR HYDROLYSATES

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2006
    XIAONA GUO
    ABSTRACT Our previous study showed that in vitro pepsin digestibility of Chinese tartary buckwheat protein was relatively low compared to those of other edible seeds. In vitro pepsin digestibilities of four protein fractions of tartary buckwheat, microstructure and molecular weight (MW) distributions of hydrolysates were investigated. In vitro pepsin digestion assay showed that the digestibilities of tartary buckwheat protein fractions were albumin (81.20%), globulin (79.56%), prolamin (66.99%) and glutelin (58.09%). Scanning electron microscopy showed that albumin and globulin fractions were digested by pitting from the outer surface to the inner part and were more digestible, while prolamin and glutelin fractions resisted digestion because only the outer surfaces of their protein bodies were digested and the interior was protected. MW distribution of the hydrolysates from the four protein fractions was determined by high-performance liquid chromatography. The hydrolysates of albumin mainly consisted of polypeptides with lower MW. The hydrolysates of glutelin had larger polypeptides together with small and medium-sized peptide fractions. [source]


    Influence of replacing brewers' grains with green tea grounds on feed intake, digestibility and ruminal fermentation characteristics of wethers

    ANIMAL SCIENCE JOURNAL, Issue 2 2008
    Chuncheng XU
    ABSTRACT An experiment was conducted to examine feed intake, apparent digestibility, nitrogen balance, ruminal fermentation and blood components of wethers fed diets containing increasing levels of wet green tea grounds (WGTG). The experimental design was a 4 × 4 Latin square with four wethers in four 15-day periods. Wethers were allowed access to diets ad libitum, and allotted to one of four treatments in which WGTG replaced 0% (no WGTG added, CTG), 5% (low level, LBG), 10% (medium level, MTG), and 15% (high level, HTG) of total mixed ration (TMR) dry matter (DM) as wet brewers grains (WBG). All TMR silages were ensiled for 120 days and, irrespective of the WGTG addition, they were well preserved with a high lactic acid content, low pH and ammonia-N contents. There were no differences among treatments in feed intake, with the exception of ether extract intake (P = 0.032). Digestibilities for LTG and MTG treatments were not different from CTG. However, the organic matter, crude protein, acid detergent fiber and energy digestibilities for HTG treatment were lower than the CTG (P < 0.05). As the level of WGTG increased, nitrogen intake did not differ, but fecal nitrogen increased (P = 0.002), while urinary nitrogen decreased (P < 0.001). No differences among treatments were found in pH level and volatile fatty acids concentrations. However, the ruminal ammonia-N of the HTG silage was lower than for the CTG silage at all times (P < 0.05). Increasing concentrations of WGTG in the TMR silage decreased (P = 0.019) plasma urea nitrogen content. Therefore, the possible mixing proportion of WGTG for TMR silages can be 10% of the diet DM. [source]


    Digestibility and nitrogen retention of diets containing different levels of fibre in local (Mong Cai), F1 (Mong Cai × Yorkshire) and exotic (Landrace × Yorkshire) growing pigs in Vietnam

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 7-8 2007
    N. T. Len
    Summary Total tract digestibility and nitrogen retention of three diets containing different levels of fibre [200, 260 and 320 g/kg neutral detergent fibre (NDF) in dry matter] were determined in three breeds of growing pig at an initial age of approximately 3.5 months. The breeds were local (Mong Cai, MC), F1 crossbred (MC × Yorkshire) and exotic (Landrace × Yorkshire, LY), allocated at random within breed (block) to double 3 × 3 Latin squares. The main fibrous ingredients of the experimental diets were rice bran, cassava residue meal and non-dehulled groundnut cake meal. Digestibility of organic matter (OM), crude protein (CP), NDF, crude fibre, gross energy (GE) and ether extract (EE) decreased as the level of dietary NDF increased (p < 0.001). The r2 values for the relationship between NDF level and digestibility of OM, CP, GE and EE were 83%, 83%, 80% and 82% respectively. On average, an increase in NDF content of 1% unit resulted in a decrease in OM, CP, GE and EE digestibility of 0.67%, 0.75%, 0.50% and 0.42% units respectively. Digestibility of energy and nutrients was the highest for MC and the lowest for LY (p < 0.01), with intermediate values for F1. There was a negative effect of NDF level on nitrogen (N) retained as a proportion of intake (p < 0.05). Nitrogen retention and utilization were significantly higher (p < 0.001) for LY than for MC and F1 pigs. [source]


    Effects of vitamin E and selenium on performance, digestibility of nutrients, and carcass characteristics of Japanese quails reared under heat stress (34 °C)

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 11-12 2001
    K. Sahin
    This study was conducted to determine the effects of vitamin E (dL-,-Tocopheryl acetate) and selenium (Se; Na2 -SeO3) on performance, digestibility of nutrients and carcass characteristics of Japanese quails reared under chronic heat stress (34 °C). A total of 120 10-day-old Japanese quails were randomly assigned to four treatment groups, three replicates of 10 birds each. The birds with a 2 × 2 factorial design received either two levels of vitamin E (125 and 250 mg/kg of diet) or two levels of Se (0.1 or 0.2 mg/kg of diet). A 250-mg vitamin E/kg of diet compared with that of 125 mg/kg of diet and higher dietary Se inclusions (0.1 vs. 0.2 mg/kg) resulted in a better performance (p=0.001). The interaction between vitamin E and Se for feed intake (p=0.03), final body weight change (p=0.03) and feed efficiency (p=0.001) was detected. Carcass yield increased with increasing both dietary vitamin E and Se (p=0.001). The interactions on carcass characteristics were all non-significant (p > 0.06). Digestibility of nutrients (DM, OM, CP and ether extract) was higher with higher dietary vitamin E (p=0.03), and DM digestibility was also higher with higher dietary Se (p=0.05). There were no interactions detected for digestibility of nutrients (p=0.28). From the results of the present study, it was concluded that a combination of 250 mg of vitamin E and 0.2 mg of Se provides the greatest performance in Japanese quails reared under heat stress and this combination can be considered as a protective management practice in Japanese quail diets, reducing the negative effects of heat stress. [source]


    Comparative foraging and nutrition of horses and cattle in European wetlands

    JOURNAL OF APPLIED ECOLOGY, Issue 1 2002
    Catherine Menard
    Summary 1Equids are generalist herbivores that co-exist with bovids of similar body size in many ecosystems. There are two major hypotheses to explain their co-existence, but few comparative data are available to test them. The first postulates that the very different functioning of their digestive tracts leads to fundamentally different patterns of use of grasses of different fibre contents. The second postulates resource partitioning through the use of different plant species. As domestic horses and cattle are used widely in Europe for the management of conservation areas, particularly in wetlands, a good knowledge of their foraging behaviour and comparative nutrition is necessary. 2In this paper we describe resource-use by horses and cattle in complementary studies in two French wetlands. Horses used marshes intensively during the warmer seasons; both species used grasslands intensively throughout the year; cattle used forbs and shrubs much more than horses. Niche breadth was similar and overlap was high (Kulczinski's index 0·58,0·77). Horses spent much more time feeding on short grass than cattle. These results from the two sites indicate strong potential for competition. 3Comparative daily food intake, measured in the field during this study for the first time, was 63% higher in horses (144 gDM kg W,0·75 day,1) than in cattle (88 gDM kg W,0·75 day,1). Digestibility of the cattle diets was a little higher, but daily intake of digestible dry matter (i.e. nutrient extraction) in all seasons was considerably higher in horses (78 gDM kg W,0·75 day,1) than in cattle (51 gDM kg W,0·75 day,1). When food is limiting, horses should outcompete cattle in habitats dominated by grasses because their functional response is steeper; under these circumstances cattle will require an ecological refuge for survival during winter, woodland or shrubland with abundant dicotyledons. 4Horses are a good tool for plant management because they remove more vegetation per unit body weight than cattle, and use the most productive plant communities and plant species (especially graminoids) to a greater extent. They feed closer to the ground, and maintain a mosaic of patches of short and tall grass that contributes to structural diversity at this scale. Cattle use broadleaved plants to a greater extent than horses, and can reduce the rate of encroachment by certain woody species. [source]


    Trypsin Inhibitor Activity In Vitro Digestibility and Sensory Quality of Meat-Like Yuba Products as Affected by Processing

    JOURNAL OF FOOD SCIENCE, Issue 3 2002
    G. Su
    ABSTRACT: : Soybeans (Glycine max) were soaked and ground to obtain soymilk. The soymilk was cooked in an open tank and held at 85 to 90 deg;C. Yuba films were picked up in 20 min intervals and dried for 20 min. Yuba films were soaked in chicken-flavor solutions (25% and 35%), and baking soda (BS) solutions (0%, 1%, 2%, and 3% BS), and cooked at 100 °C for 30 min, 60 min, and 90 min. TIA decreased (p < 0.05) with the increase of heating time and BS concentration. In vitro protein digestibility (IVPD) decreased with heating time and BS concentration (p < 0.05). Sensory characteristics were affected by flavor concentration. By using 0% BS, 25% of the chicken flavor concentration, and a short heating time method, meat-like products with low TIA, high IVPD, and good sensory characteristics were obtained. [source]


    Evaluation of In Vitro Apparent Protein Digestibility by Shrimp Using Gut Enzyme Extracts

    JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2009
    Joe M Fox
    Knowledge of apparent protein digestibility (APD) is required for optimization of feed formulae for the production of marine penaeid shrimp. The purpose of this study was to evaluate an in vitro method for determining APD in marine penaeid shrimp using gut enzyme extracts. A high correlation (r2 = 0.95) was shown between single-ingredient APD values for fish meal diets using in vivo methodology and those derived from in vitro testing of ingredients. A second study showed positive correlation (r2 = 0.71) between in vitro APD of selected purified and semipurified ingredients and their reported in vivo APDs. This correlation was much higher for purified ingredients (r2 = 0.93) versus less-refined ingredients (r2 = 0.24). A third trial compared in vitro APD at three different enzyme extract pH values and showed that for most protein sources, APD was significantly highest (P < 0.05) at pH = 7.0 and lower at pH = 6.1 or 7.9, indicating a neutral pH optimum for this methodology. [source]


    The effect of dietary ratios of corn silage and alfalfa hay on carbohydrate digestion and retention time of feed particles in the gastrointestinal tract of steers

    ANIMAL SCIENCE JOURNAL, Issue 5 2009
    Taketo OBITSU
    ABSTRACT Four Holstein steers fitted with duodenal cannula were used in a 4 × 4 Latin square design to investigate the effect of the combination of corn silage (CS) and alfalfa hay (AH) in different ratios on the ruminal and intestinal digestion of carbohydrates and feed particle passage rate. Steers were fed mixed diets containing both CS and AH in ratios of 80:20, 60:40, 40:60 and 20:80 on a dry matter basis at 95% of ad libitum feed intake. The increase of AH proportion in diets increased dry matter intake and ruminal digestion of dry matter, non-fiber carbohydrate, neutral and acid detergent fiber linearly. Ruminal digestibility of neutral detergent fiber showed a quadratic response, and total digestibility increased linearly with increasing AH proportion. Digestibility of acid detergent fiber in the rumen was not affected by the dietary treatments, but the total tract digestibility increased as the AH proportion increased. Mean retention time of feed particles in total compartment increased when the AH proportion increased from 20% to 60%, but decreased with further increase of the AH proportion. These results indicate that moderate combinations of CS and AH have an associative effect on ruminal fiber digestion, modifying particle movement in the rumen. [source]


    Effect of flow parameters of rumen digesta on effective degradability and microbial yield in sheep

    ANIMAL SCIENCE JOURNAL, Issue 4 2009
    Toshiyoshi ICHINOHE
    ABSTRACT The aim of this experiment was to examine the effect of rumen digesta flow parameters on effective degradability (EDG) and microbial nitrogen (MBN) yield in sheep fed diets of identical provision of both metabolizable energy and rumen degradable nitrogen (RDN). Ruminal degradation parameters of early-harvested perennial ryegrass hay (EH), late-harvested perennial ryegrasses hay (LH) and winter sown barley straw (BS) were determined by a nylon bag technique. Subsequently, three experimental diets (EHD, LHD and BSD) were formulated using the tested forages, sucrose and urea as supplements. An in vivo feeding study was conducted using four rumen cannulated sheep in a partial Latin square design. Digestibility, rate constants of rumen particle breakdown and passage, ruminal fermentation parameters and MBN supply to the small intestine were determined. Animals thoroughly consumed the forages fed at a restricted level. Digestion coefficients were greater for EHD than for LHD and were lowest for BSD (P < 0.05). The rate constant of large particle breakdown was 4.3, 5.9 and 6.7 %/h, respectively, and small particle passage was 5.3, 4.7 and 6.3 %/h for EHD, LHD and BSD, respectively. The estimates differed (P < 0.05) between the diets. The overall passage rate constant of total rumen particles was estimated to be higher for BSD than that for EHD or LHD (P < 0.05). Ruminal fermentation parameters were unaffected by dietary treatments (P > 0.05). Intake levels of rumen degradable organic matter (RDOM) and RDN were estimated to be greater for LHD than that for EHD or BSD (P < 0.05). Although dietary arrangements were made to give identical microbial efficiency, the estimated value was higher for EHD than that for LHD or BSD (P < 0.05); and the MBN yield for BSD was estimated to be lower than that for EHD or LHD (P < 0.05). Rumen kinetic parameters of degradation and particle flow of forage affected EDG values and MBN yield from forage-related RDN intake, although those had little effect on the efficiency of MBN yield from forage-related RDOM intake. [source]


    Effects of ruminal dosing of mechanical stimulating brush on digestibility and rumen fermentation status in Holstein steers fed low rice straw at different lengths

    ANIMAL SCIENCE JOURNAL, Issue 1 2004
    Ken-ichi HORIGUCHI
    ABSTRACT The objectives of the present study were to determine the effect of ruminal dosing of mechanical stimulating brush (Rumen faibu; RF) on digestibility and on rumen fermentation status in Holstein steers fed high concentrate and low rice straw. Eight steers (461 kg in average bodyweight) were used. Four steers were orally dosed three RF per head (RF-dosing) and the other four were not dosed (non-RF). All steers were fed enough concentrate and rice straw to gain 1.4 kg/day in bodyweight. Rice straw was cut 2 cm and 30 cm. The organic cell wall content of feeding diets was 17% in dry matter basis. Digestibility and nutritive value were not affected by RF dosing and length of rice straw. Ruminal pH was significantly lower in RF-dosing group than in non-RF group after feeding, and tended to be higher in long rice straw than in short rice straw throughout the day. There were no clear difference on total volatile fatty acid concentration and molar proportion of volatile fatty acid by RF dosing and length of rice straw throughout examined period. These present results suggest that digestibility and rumen fermentation status are not affected by RF dosing when organic cell wall content of feeding diets is approximately 17% in dry matter with rice straw over 2 cm. [source]


    Partial or total replacement of fish meal by local agricultural by-products in diets of juvenile African catfish (Clarias gariepinus): growth performance, feed efficiency and digestibility

    AQUACULTURE NUTRITION, Issue 3 2010
    L. NYINA-WAMWIZA
    Abstract The study was undertaken to evaluate the growth performance and feed utilization of African catfish, Clarias gariepinus, fed six diets (D) in which fishmeal (FM) was gradually replaced by a mixture of local plant by-products. In diets 1 and 2, FM (250 g kg,1) was replaced by sunflower oil cake (SFOC). In diets 3 and 4, FM (250 and 150 g kg,1, respectively) was replaced by SFOC and bean meal (BM) while FM was totally substituted by a mixture of groundnut oil cake (GOC), BM and SFOC in diets 5 and 6. Sunflower oil cake was cooked, soaked or dehulled in order to determine the appropriate processing techniques for improving the SFOC nutritive value and to evaluate the apparent digestibility coefficient (ADC) values of the alternative diets. No significant differences were observed for daily feed intake, weight gain, specific growth rate (SGR) and feed efficiency (FE) among fish fed D1, D2, D3 (250 g kg,1 FM), D4 (150 g kg,1 FM) and D6 (0 g kg,1 FM). The highest SGR (3.2% per day) and FE (1.2) were achieved in fish fed D3, and the lowest in fish fed D5 (0% FM), suggesting a maximum acceptable dietary concentration of hulled SFOC below 250 g kg,1 in African catfish juveniles. Protein efficiency ratio ranged from 2.2 to 3.2 for all dietary treatments and was positively influenced by FM inclusion. African catfish were able to digest plant protein very efficiently in all diets tested. ADC of protein ranged from 88.6 to 89.5%, while ADC of energy was relatively low for diets containing hulled sunflower oilcake (71,74%) and high when sunflower oilcake was dehulled (78.6,81.3%). Similarly, ADC of dry matter was higher when sunflower was dehulled (72.1%) when compared with crude SFOC (60.5%). Soaking increased ADC values for neutral detergent fibre (NDF), dry matter, energy, protein and amino acids (AA). There were no significant differences in protein ADCs (88,90%) with increased levels of dietary vegetable ingredients. Both soaking and dehulling of sunflower before incorporation helped in the reduction of NDF, antitrypsin and tannins. Digestibility of all AA was generally high, greater than 90% for both indispensable and non-indispensable AA. Based on the data obtained, it was possible to totally replace menhaden fish meal with a mixture of vegetable proteins (72% of total dietary protein) when diets contained a relatively low percentage of animal protein (28% based on blood meal and chicken viscera meal) without negative effects. [source]


    Digestibility of Calanus finmarchicus wax esters in Atlantic salmon (Salmo salar) freshwater presmolts and seawater postsmolts maintained at constant water temperature

    AQUACULTURE NUTRITION, Issue 5 2009
    A. OXLEY
    Abstract Calanoid copepods are a rich source of marine lipid for potential use in aquafeeds. Copepod oil is primarily composed of wax esters (WE) and there are concerns over the efficiency of wax ester, versus triacylglycerol (TAG), digestion and utilization in fish. As smoltification represents a period of major physiological adaptation, the present study examined the digestibility of a high WE diet (Calanus oil; 48% WE, 26% TAG), compared with a TAG diet (fish oil; 58% TAG), in Atlantic salmon freshwater presmolts and seawater postsmolts, of similar age (9 months) and weight (112 g and 141 g initial, respectively), over a 98-day period at constant temperature. Fish grew significantly better, and possessed lower feed conversion ratios (FCR), in seawater than freshwater. However, total lipid apparent digestibility coefficient (ADC) values were significantly lower in seawater fish, as were total fasted bile volumes. Dietary Calanus oil also had a significant effect, reducing growth and lipid ADC values in both freshwater and seawater groups. Postsmolts fed dietary Calanus oil had the poorest lipid ADC values and analysis of faecal lipid class composition revealed that 33% of the remaining lipid was WE and 32% fatty alcohols. Dietary prevalent 22:1n-11 and 20:1n-9 fatty alcohols were particularly poorly utilized. A decrease in primary bile acid, taurocholate, concentration was observed in the bile of dietary Calanus oil groups which could be related to the lower cholesterol content of the diet. The dietary WE : TAG ratio is discussed in relation to life stage and biliary intestinal adaptation to the seawater environment postsmoltification. [source]


    Performance factors, body composition and digestion characteristics of gilthead sea bream (Sparus aurata) fed pelleted or extruded diets

    AQUACULTURE NUTRITION, Issue 4 2009
    B. VENOU
    Abstract The effects of steam pelleting or extrusion of a commercial feed on performance of 2 g (small) and 40 g (large) gilthead sea bream was studied. In addition the apparent digestibility of diets, gastric evacuation time (GET) and trypsin and amylase activities were measured in large fish. Fish size significantly increased protein and energy productive value, body protein and lipid, liver glycogen and liver lipid, however decreased daily growth index, feed intake and feed utilization, body moisture and hepatosomatic index. Extrusion processing decreased feed intake, more strongly for small fish, and increased daily growth index, feed utilization, protein and energy productive value, body protein and lipid. Digestibility of starch and energy increased with extrusion and GET of extruded feed was double that of steam-pelleted conditioned feed (i.e. 544 min versus 284 min). Digestive enzyme activities approached maximum values after 240 min for the pelleted diet, while those of the extruded continued to increase, at higher rates for amylase than trypsin. Pelleted diet indicated higher moisture for stomach digesta, while the moisture of the intestinal precipitate indicated a higher water-binding capacity for the extruded diet. The overall results indicate a better assimilation of the extruded diet, which could result from its prolonged gastric evacuation. [source]


    Digestibility and growth performance of juvenile rainbow trout (Oncorhynchus mykiss) fed with pea and canola products

    AQUACULTURE NUTRITION, Issue 2 2003
    D.L. Thiessen
    A digestibility experiment and subsequent 84-day feeding experiment evaluated the use of pea and canola meal products in diets for rainbow trout. The effect of milling and heat treatment on nutrient, dry matter and energy digestibility of raw/whole peas, raw/dehulled peas, extruded/dehulled peas and autoclaved air-classified pea protein was determined. Digestibility of the protein component was uniformly high for all pea ingredients (90.9,94.6%), regardless of the processing treatment. Autoclaving or extrusion increased starch digestibility by 41,75% (P , 0.05), which consequently increased energy and dry matter digestibility of whole and dehulled peas. Autoclaved air-classified pea protein had superior protein (94.6%), energy (87.0%) and dry matter (84.0%) digestibility (P , 0.05). It was demonstrated that inclusion of 25% dehulled peas, 20% air-classified pea protein or 20% canola meal fines was feasible in trout diets allowing for replacement of soya bean meal. The data showed no difference (P , 0.05) in feed intake, final weight and specific growth rate (SGR) measurements, and feed utilization was not compromised with inclusion of pea or canola meal products as the primary plant ingredient. It was concluded that dehulled peas, air-classified pea protein and canola meal fines are suitable ingredients for use in trout diet formulation at a level of 20%. [source]


    Carbohydrate utilization by juvenile silver perch, Bidyanus bidyanus (Mitchell).

    AQUACULTURE RESEARCH, Issue 2 2003

    Abstract The ability of silver perch (Bidyanus bidyanus) to digest and utilize dietary starch or starch breakdown products was investigated. For experiment 1 the ability of silver perch (2.7 ± 0.01 g) to digest wheat starch at two dietary inclusion levels (30% or 60%), each at four levels of gelatinization (0%, 25%, 50% or 80%), was investigated over a 31-day period. For experiment 2, the ability of silver perch (15.9± 0.25 g) to digest wheat starch, dextrin (at three levels of dextrinization), maltose, glucose and pea starch, all at the 30% inclusion level, was investigated over a 41-day period. Water temperature for both experiments was 25 ± 1 °C. Apparent digestibility coefficients (ADCs) for starch, dry matter (DM) and energy were affected by both degree of gelatinization (80% > 50% > 25% = 0%) and inclusion level (30% > 60%). Specific growth rate (SGR) was unaffected by the inclusion of 30% starch; however, it was reduced at the 60% starch content level. Degree of gelatinization had no effect on SGR. For experiment 2, there were significant differences between carbohydrate and DM ADCs for the test ingredients. The carbohydrate, DM and energy ADCs were ranked as follows: dextrin (Fieldose 9) = dextrin (Fieldose 17) = dextrin (Fieldose 30) = gelatinized wheat starch = maltose = glucose > raw wheat starch > raw pea starch. The protein ADC of the diets, postprandial plasma glucose concentration and SGR were all unaffected by ingredient type. For both experiments, HSI tended to increase with carbohydrate inclusion. Liver glycogen concentrations were also elevated, but muscle glycogen and liver and muscle triacylglycerol concentrations were unaffected. Digestibility of starch by silver perch is clearly affected by inclusion content and processing. [source]


    Neural Network Prediction of Biomass Digestibility Based on Structural Features

    BIOTECHNOLOGY PROGRESS, Issue 2 2008
    Jonathan P. O'Dwyer
    Plots of biomass digestibility are linear with the natural logarithm of enzyme loading; the slope and intercept characterize biomass reactivity. The feed-forward back-propagation neural networks were performed to predict biomass digestibility by simulating the 1-, 6-, and 72-h slopes and intercepts of glucan, xylan, and total sugar hydrolyses of 147 poplar wood model samples with a variety of lignin contents, acetyl contents, and crystallinity indices. Regression analysis of the neural network models indicates that they performed satisfactorily. Increasing the dimensionality of the neural network input matrix allowed investigation of the influence glucan and xylan enzymatic hydrolyses have on each other. Glucan hydrolysis affected the last stage of xylan digestion, and xylan hydrolysis had no influence on glucan digestibility. This study has demonstrated that neural networks have good potential for predicting biomass digestibility over a wide range of enzyme loadings, thus providing the potential to design cost-effective pretreatment and saccharification processes. [source]


    Effect of fermentation on in vitro digestibilities and the level of antinutrients in moth bean [Vigna aconitifolia (Jacq.) Marechal]

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2008
    Amrit Bhandal
    Summary The effect of fermentation with varying temperatures and time periods on the nutritive value of Moth bean was studied. Results indicated that at 30 °C, protein digestibility increased from 60% in the non-processed moth bean to 77%, 78% and 80% and at 35 °C, increased to 81%, 83% and 85% following 12, 18 and 24 h of fermentation (controlled) period, respectively. Fermentation also caused an appreciable enhancement (96,133%) in starch digestibility with increase in period and temperature of fermentation. Fermentation of moth bean resulted in 24,34% reduction in phytic acid content at 30 °C and 33,42.5% at 35 °C. Polyphenol content was reduced by 42%, 48% and 51% at 30 °C and by 44%, 49% and 54% at 35 °C after 12, 18 and 24 h of fermentation period, respectively. Prolonging the period of fermentation from 12 to 18 and 24 h at 30 °C also caused a loss in TIA. [source]


    Feeding value of enset (Ensete ventricosum), Desmodium intortum hay and untreated or urea and calcium oxide treated wheat straw for sheep

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1 2009
    A. Nurfeta
    Summary Feed intake, in vivo nutrient digestibility and nitrogen utilization were evaluated in male sheep fed different fractions (leaf, pseudostem, corm, whole plant) of enset, untreated or 2% urea- and 3% calcium oxide- (CaO or lime) treated wheat straw and Desmodium intortum hay as sole diets. All feeds, except D. intortum hay and enset leaf had low crude protein (CP) content. Non-fiber carbohydrate contents were higher in enset fractions, especially in pseudostem and corm relative to other feeds. Enset leaf and pseudostem had high calcium, phosphorus and manganese contents. Corm, whole enset and D. intortum hay were rich sources of zinc. Daily dry matter and CP intakes were higher (p < 0.05) in sheep fed D. intortum hay (830 and 133 g, respectively) than those fed pseudostem (92 and 7.8 g, respectively). Organic matter digestibilities were highest for corm (0.780) and whole enset (0.776) and lowest for D. intortum hay (0.534) and untreated wheat straw (0.522). The CP digestibility ranged from 0.636 in D. intortum hay to 0.408 in corm. Nitrogen (N) balance was highest (p < 0.05) in D. intortum hay (10.4 g/day) and lowest in corm (,1.3 g/day). Enset leaf could be a useful protein supplement whereas the pseudostem and corm could be good sources of energy. [source]


    Yttrium oxide (Y2O3) as an inert marker in digestibility studies with dogs, blue foxes and mink fed diets containing different protein sources

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 9-10 2007
    S. G. Vhile
    Summary The study evaluated the use of yttrium oxide (Y2O3) as an inert marker in studies of apparent total tract digestibility in dogs, blue foxes and mink. Comparison was made with total faecal collection, and use of chromic oxide (Cr2O3) as marker respectively. Four experimental diets were added 0.1 g/kg yttrium oxide and 10 g/kg chromic oxide and fed to four animals of each species. Faecal recovery of yttrium oxide was 94.4% (SEM ± 1.0), and of chromic oxide 105.8% (SEM ± 1.5). The digestibilities of dry matter, crude protein, crude fat, starch and total carbohydrates obtained by total collection and yttrium oxide as marker showed close similarity, and in most cases not significant differences, independent of species and diets. In dogs, overall digestibilities of main nutrients with chromic oxide as marker were not significantly different from overall means obtained with yttrium oxide (p > 0.05). Overall digestibility of dry matter, crude protein and total carbohydrates in blue foxes and mink was significantly higher with chromic oxide than with yttrium oxide (p < 0.05). In dogs and blue foxes, digestibilities of individual amino acids determined by use of yttrium oxide were not different from values obtained using total collection of faeces, both within diets and for overall mean (p > 0.05). Overall amino acid digestibilities in dogs determined with chromic oxide as marker were similar to corresponding figures for yttrium oxide, whereas use of chromic oxide resulted in significantly higher digestibilites for a number of amino acids compared with yttrium oxide in foxes and mink (p < 0.05). The digestibilities of most main nutrients and amino acids revealed no interaction between diet and method (p > 0.05). The study showed that yttrium oxide can be used in low concentration in the feed, and allows high accuracy of analyses and thereby precise digestibility determination. It is concluded that yttrium oxide is an alternative inert marker to chromic oxide in the studied species. [source]


    Supplementation of xylanase and phospholipase to wheat-based diets for weaner pigs

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 9-10 2005
    G. Diebold
    Summary The effects of supplementing a wheat-based diet for weaner pigs with exogenous xylanase and phospholipase on ileal and faecal nutrient digestibilities and on the level of microbial metabolites in ileal digesta were examined. Fourteen piglets, weaned at 11 days, were fitted with a simple T-cannula at the distal ileum. The pigs were offered a control diet or diets supplemented with xylanase and phospholipase individually or in combination, in a two period crossover design. The combination of xylanase and phospholipase tended to increase the ileal recovery of the amino sugar galactosamine, whereas the concentration expressed in mg/kg dry matter intake of glucosamine was slightly decreased (p < 0.10). There was neither an effect of enzyme supplementation on ileal and faecal digestibility of the other nutrients and energy, nor was there an effect on pH and on the level of microbial metabolites in ileal digesta. However, an increase in ileal and faecal nutrient and energy digestibility with increasing age was observed. The ileal and faecal digestibility coefficients (except for ether extract) were significantly (p < 0.05) higher in experimental period I than in period II. These higher values may be attributed to a lower feed intake during period I. Since a lower level of feed intake is generally associated with a slower rate of passage and a longer retention time of digesta, a positive impact on digestion and absorption of nutrients can be assumed, which, on the other hand, limits the potential of additional enzyme effects. [source]


    Studies on feed digestibilities in captive Asian elephants (Elephas maximus)

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3-4 2003
    M. Clauss
    Summary In order to test the suitability of the horse as a nutritional model for elephants, digestibility studies were performed with six captive Asian elephants on six different dietary regimes, using the double marker method with acid detergent lignin as an internal and chromium oxide as an external digestibility marker. Elephants resembled horses in the way dietary supplements and dietary crude fibre content influenced digestibility, in calcium absorption parameters and in faecal volatile fatty acid composition. However, the absolute digestibility coefficients achieved for all nutrients are distinctively lower in elephants. This is because of much faster ingesta passage rates reported for elephants. No answer is given to why elephants do not make use of their high digestive potential theoretically provided by their immense body weight. Differences in volatile fatty acid concentrations between these captive elephants and those reported from elephants from the wild are in accord with a reported high dependence of free-ranging elephants on browse forage. Zusammenfassung Untersuchungen zur Verdaulichkeit von Futtermitteln bei Asiatischen Elefanten (Elephas maximus) Um zu überprüfen, ob das Pferd als ernährungsphysiolgisches Modelltier für Elefanten herangezogen werden kann, wurden Verdaulichkeitsstudien an sechs im Zoo gehaltenen Indischen Elefanten mit sechs verschiedenen Futterrationen durchgeführt. Dabei wurde die Doppelindikatormethode mit Lignin als internem und Chromoxid als externem Marker verwendet. Elefanten ähnelten Pferden hinsichtlich der Art und Weise, wie sich Ergänzungsfuttermittel und der Rohfasergehalt der Ration auf die Verdaulichkeit auswirkten, hinsichtlich der Kalziumabsorption, und hinsichtlich der Zusammensetzung der flüchtigen Fettsäuren im Kot. Die von Elefanten erzielten absoluten Verdaulich-keitswerte sind jedoch für alle Nährstoffe deutlich niedriger als bei Pferden, was auf die schnellere Passage der Ingesta durch den Verdauungstrakt der Elefanten zurückzuführen ist. Die Frage, warum Elefanten ihr großes Potential zu hohen Verdauungleistungen nicht ausnutzen, das ihnen theoretisch aufgrund ihrer immensen Körpermasse gegeben ist, ist noch nicht beantwortet. Unterschiede in den Konzentrationen von flüchtigen Fettsäuren im Kot zwischen diesen Zoo-Elefanten und Elefanten aus freier Wildbahn spiegeln den hohen Laubanteil in der Nahrung freilebender Tiere wieder. [source]


    Untersuchungen an wachsenden Schweinen zum Futterwert einer neuen Ackerbohnensorte (Vicia faba L.) bei Ergänzung mit DL -Methionin oder DL -Methionin-Hydroxyanalog

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2002
    HJ. ABEL
    Investigations in growing pigs on the feeding value of a new cultivar of field beans (Vicia faba L.) supplemented with DL -methionine or DL -methionine-hydroxyanalogue A basal control mixture of barley, soy bean meal and soy bean oil was replaced by 25% of the new field bean-cultivar `Divine' and the resulting two mixtures were supplemented with minerals, trace elements, vitamins and amino acids according to the ideal protein concept. The control diet was adjusted with DL -methionine (DL -Met), the field bean mixture either with DL -Met or DL -methionine-hydroxyanalogue (DL -MHA) assuming biological equivalence on a molar basis for both supplements. The three experimental diets were fed to growing pigs (35,40 kg bwt.). Spontaneous urine samples were analysed separately for determining parameters that characterize the acid-base status of the pigs. There were no significant differences between experimental groups in nutrient digestibilities. The level of bacterially fermentable substances was increased in the diets containing field beans. The field beans contained 14 mg ME/kg DM. There were no significant (p < 0,05) differences in N- and mineral-retentions (Ca, P, Na, K) between the treatments. The stronger alkalinity found in urine after feeding the field bean mixtures resulted from a higher electrolyte balance of the diet. Eine Kontrollration aus Gerste, Sojaschrot und Sojaöl wurde zu 25% durch Ackerbohnen der neugezüchteten Sorte `Divine' ersetzt und beide Mischungen mit Mineral- und Wirkstoffen sowie Aminosäuren ergänzt. Die Ergänzung mit Methionin erfolgte in der Kontrollmischung mit DL -Methionin, in der Ackerbohnenmischung mit DL -Methionin (DL -Met) oder DL -Methionin-Hydroxyanalog (DL -MHA) unter Zugrundelegung der molaren Wirkungsäquivalenz der beiden Supplemente. Die resultierenden drei Futtermischungen wurden in Stoffwechselversuchen an Schweine (35,40 kg LM) gefüttert. Separate Spontanharnproben wurden auf Parameter des Säure-Basen-Haushalts der Tiere untersucht. Zwischen den Versuchsgruppen traten keine signifikanten Unterschiede in den Nährstoffverdaulichkeiten auf. Die Gehalte an bakteriell fermentierbarer Substanz wurden durch Ackerbohnen erhöht. Der Gehalt der Ackerbohnen an umsetzbarer Energie lag bei 14 MJ ME/kg T. Die N- und Mineralstoffretentionen (Ca, P, Na, K) der Schweine unterschieden sich zwischen den Fütterungsgruppen nicht signifikant (p < 0,05). Die bei Ackerbohnenfütterung gesteigerte Harn-Alkalität ließ sich auf erhöhte kaliumbedingte Elektrolytbilanzen des Futters zurückführen. [source]


    Effects of dietary protein level and cold exposure on tissue responsiveness and sensitivity to insulin in sheep

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 11-12 2001
    H. Sano
    The effects of dietary crude protein (CP) level and cold exposure on tissue responsiveness and sensitivity to insulin were studied in sheep. Nine rams were assigned to one of three isoenergetic diets which contained 70, 100, and 140% of CP for maintenance. They were exposed from a thermoneutral environment (20 °C) to a cold environment (0 °C) for 7 days. A hyperinsulinemic euglycemic clamp approach was applied for the determination of tissue responsiveness to insulin (the maximal glucose infusion rate, GIRmax) and tissue sensitivity to insulin (the plasma insulin concentration at half maximal glucose infusion rate, ED50). Dietary CP level influenced digestibilities of dry matter and CP (P=0.002 and P=0.001, respectively), and cold exposure decreased (P=0.01) CP digestibility. The GIRmax and ED50 tended to be influenced (P=0.08) by dietary CP level. The GIRmax was enhanced (P=0.0001) during cold exposure. Significant interactions between diet and environment were found for the GIRmax (P=0.04), but not for ED50 (P=0.07). It is concluded that in sheep dietary CP level can modify insulin action in response to cold exposure. [source]


    Changes in immune and enzyme histochemical phenotypes of cells in the intestinal mucosa of Atlantic salmon, Salmo salar L., with soybean meal-induced enteritis

    JOURNAL OF FISH DISEASES, Issue 2 2000
    A M Bakke-McKellep
    Extracted soybean meal (SBM) in the diet for Atlantic salmon, Salmo salar L., causes an inflammatory response in the distal intestine. The morphological changes of the epithelial cells and a characterization of the inflammatory cell infiltrate of the distal intestinal mucosa were studied using a panel of enzyme and immunohistochemical markers. The salmon (average body weight 927 g) used in the study were fed either a fishmeal-based diet (control diet) or a diet in which 30% of the fishmeal protein was replaced with SBM protein (SBM diet). In salmon fed SBM, there were markedly reduced enzyme reactivities in the distal intestinal epithelial cells, both in the brush border [5,-nucleotidase (5,N), Mg2+-ATPase, alkaline phosphatase (ALP) and leucine aminopeptidase (LAP)] and in the intracellular structures [alkaline and acid phosphatase, non-specific esterase (NSE) and alanine aminopeptidase (AAP)]. There appeared to be an increased presence of cells of monocytic lineage, including macrophages, as well as neutrophilic granulocytes and immunoglobulin (Ig) M in the lamina propria of the SBM-fed fish. The mid intestine showed little response to the diet. The results suggest that toxic/antigenic component(s) of SBM affect the differentiation of the distal intestinal epithelial cells and may help explain the reduced nutrient digestibilities previously reported in salmonids fed extracted SBM. [source]


    IN VITRO DIGESTIBILITY OF CHINESE TARTARY BUCKWHEAT PROTEIN FRACTIONS: THE MICROSTRUCTURE AND MOLECULAR WEIGHT DISTRIBUTION OF THEIR HYDROLYSATES

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2006
    XIAONA GUO
    ABSTRACT Our previous study showed that in vitro pepsin digestibility of Chinese tartary buckwheat protein was relatively low compared to those of other edible seeds. In vitro pepsin digestibilities of four protein fractions of tartary buckwheat, microstructure and molecular weight (MW) distributions of hydrolysates were investigated. In vitro pepsin digestion assay showed that the digestibilities of tartary buckwheat protein fractions were albumin (81.20%), globulin (79.56%), prolamin (66.99%) and glutelin (58.09%). Scanning electron microscopy showed that albumin and globulin fractions were digested by pitting from the outer surface to the inner part and were more digestible, while prolamin and glutelin fractions resisted digestion because only the outer surfaces of their protein bodies were digested and the interior was protected. MW distribution of the hydrolysates from the four protein fractions was determined by high-performance liquid chromatography. The hydrolysates of albumin mainly consisted of polypeptides with lower MW. The hydrolysates of glutelin had larger polypeptides together with small and medium-sized peptide fractions. [source]


    Evaluation of Nondigested Carbohydrates in Hydroxypropylated Tapioca Starch

    JOURNAL OF FOOD SCIENCE, Issue 1 2010
    M. Tachibe
    ABSTRACT:,In vitro,and,in vivo,digestibilities of hydroxypropyl starch were investigated to determine an appropriate nondigested carbohydrate assaying method for hydroxypropyl starch. Hydroxypropyl tapioca starch (HPTS), with a 0.338 degree of substitution, was used as a hydroxypropyl starch source. Practically all nondigested carbohydrate in HPTS was low molecular weight and was not precipitated in 78% ethanol. The contents of nondigested carbohydrate in HPTS and in effluents of ileorectomized rats fed the HPTS diet obtained by the AOAC 2001.03 (enzyme-gravimetric-HPLC method) were almost the same, 56% and 59%, respectively. The recovery of hydroxypropyl groups from ileorectomy effluents was 98%. The AOAC 2001.03 method is suggested to be appropriate in determining the content of nondigested carbohydrates in hydroxypropyl starch. [source]


    Evaluation of alternative cereal sources in dog diets: effect on nutrient utilisation and hindgut fermentation characteristics

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2009
    Kumar B Kore
    Abstract BACKGROUND: Rice is one of the most commonly used cereal grains in pet foods. However, other cereals such as pearl millet, sorghum and maize have good amino acid profiles and could be used as alternatives to rice in the diet of dogs, thus sparing rice for human consumption. The aim of this study was to evaluate the nutritional worth of these cereals for pet dogs. RESULTS: Eight adult Spitz dogs (age ,10 months, average body weight 6.14 ± 0.58 kg) were used in a 4 × 4 replicated Latin square design to compare the effects of dietary inclusion of four cereals, namely rice, maize, pearl millet and sorghum, on digestibility and hindgut fermentation characteristics. The digestibility of dry matter (DM) was significantly (P < 0.01) reduced when rice was replaced by the alternative cereals. Additionally, the digestibilities of protein, fat and total dietary fibre decreased (P < 0.01) in dogs fed the pearl millet-based diet. The DM voided in faeces increased (P < 0.05) when rice was replaced by the alternative cereals. Faecal ammonia concentration was higher (P < 0.05) on the rice-based diet, while faecal lactate concentration was reduced (P < 0.01) on the pearl millet- and sorghum-based diets. CONCLUSION: The results suggest that maize, pearl millet and sorghum are not as effectively utilised as rice as cereal source in the diet of dogs. Copyright © 2009 Society of Chemical Industry [source]


    Estimates of basal ileal endogenous losses of amino acids by regression analysis and determination of standardised ileal amino acid digestibilities from casein in newly weaned pigs,

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2008
    Meike Eklund
    Abstract BACKGROUND: This study was carried out to estimate basal ileal endogenous crude protein (CP) and amino acid (AA) losses (IAALB) in newly weaned pigs by regression analysis from apparent ileal digestible and the corresponding total dietary contents of CP and AA in order to obtain standardised ileal digestibilities (SID) of CP and AA originating from casein. A total of fourteen 3-week-old barrows were fitted with simple T cannulas at the distal ileum and were fed six diets with two pigs per diet in 4 weekly repeated measurements. Corn starch-based diets containing six graded levels of CP from casein with 90, 155, 220, 285, 350 and 415 g kg,1 CP (as-fed basis) were formulated. RESULTS: Linear relationships (P < 0.001) between apparent ileal digestible and total dietary contents of CP and AA (g kg,1 dry matter intake (DMI)) exist for CP and all AA in the range of 90,220 g kg,1 CP content in the diet. The IAALB extrapolated from the range of 90,220 g kg,1 CP content are different from zero (P < 0.001 to P = 0.019) except for tryptophan (P = 0.220). Based on regression analysis in the range of 90,220 g kg,1 CP, estimates of IAALB, expressed as g kg,1 DMI, and SID of CP and AA in casein (in parentheses, %) were as follows: CP 9.3 (98.0); arginine 0.4 (98.9); histidine 0.2 (98.5); isoleucine 0.2 (98.1); leucine 0.5 (99.2); lysine 0.4 (99.0); methionine 0.1 (99.1); phenylalanine 0.4 (99.9); threonine 0.6 (97.8); tryptophan 0.1 (96.2); valine 0.4 (98.5). CONCLUSION: The IAALB and SID of CP and AA originating from casein in newly weaned pigs are in close agreement with values obtained in grower finisher pigs. Copyright © 2007 Society of Chemical Industry [source]


    Nutritional evaluation of peas for ducks

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2004
    Charles M Nyachoti
    Abstract The nutritive value of four pea cultivars (AC Advantage, Carneval, CDC Mozart and Keoma) and soybean meal (SBM) was evaluated in a 102 h study with 48 male White Pekin ducks. All birds were tube-fed 25 g of dextrose at 24 and 30 h after feed withdrawal, then 25 g of each feedstuff was tube-fed to eight ducks at 48 and 54 h after feed withdrawal. Excreta were quantitatively collected during the next 54 h. Endogenous nitrogen, amino acids and energy per bird in the 54 h collection period were 1.06 ± 0.58 g, 0.047 ± 0.025 g and 0.098 ± 0.049 MJ respectively. There were differences (P < 0.05) in apparent amino acid digestibilities (AAAD) and true amino acid digestibilities (TAAD). On average, AAAD were 82.8, 82.0, 70.3, 82.4 and 77.7% and TAAD were 89.4, 89.2, 82.3, 89.5 and 85.3% for SBM, AC Advantage, Carneval, CDC Mozart and Keoma respectively. The nitrogen-corrected apparent and true metabolisable energy values did not differ among the pea diets and were 13.36 ± 0.071 and 14.59 ± 0.071 MJ kg,1 respectively. Respective values for SBM were 12.16 ± 0.16 and 13.39 ± 0.16 MJ kg,1 and both were lower (P < 0.05) than in peas. Copyright © 2004 Society of Chemical Industry [source]


    Nutrient utilisation and performance of broilers in response to processed flaxseed dietary levels and vitamin B6 supplementation

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2003
    Yingran Shen
    Abstract The objective of this study was to determine the effects of processing and dietary inclusion level of flaxseed on broiler performance and nutrient utilisation. Flaxseed was included in the diet fed to day-old broilers for the first 3 weeks as whole seed, ground seed, autoclaved whole seed, ground autoclaved whole seed or whole seed pelleted with the other ingredients, at levels of 0, 100, 120 and 140 g kg,1. Chicks fed the pelleted flaxseed-containing diets had heavier body weights, consumed more feed and had better feed/gain ratios than those fed the other flaxseed-containing diets during the 3 weeks period (P < 0.01). The flaxseed level in the diet also had very significant (P < 0.01) effects on body weight and feed/gain ratio at the end of weeks 1 and 3, with the diets containing 100 g kg,1 flaxseed resulting in better performance than the other flaxseed-containing diets. Among the flaxseed containing diets, the pelleted diets led to higher apparent ether extract digestibilities, with values of 778 and 770 g kg,1 for the diets containing 100 and 140 g kg,1 flaxseed respectively. This better utilisation of ether extract by young broilers may explain the significantly (P < 0.05) higher AMEn (apparent metabolisable energy) value of 2924 kcal kg,1 for the pelleted 140 g kg,1 flaxseed-containing diet. This was 15.4,17.5% higher than for the diets with the same level of flaxseed but provided as raw or autoclaved whole seed. The pelleting of flaxseed allowed an inclusion rate of 100 g kg,1 without any reduction in the performance and nutrient utilisation of broilers. Copyright © 2003 Society of Chemical Industry [source]