Iron, Zinc, Copper and Magnesium Binding by Cooked Pinto Bean (Phaseohs vulgaris) Neutral and Acid Detergent Fiber

Iron, copper and zinc but not magnesium were bound by neutral (NDF) and acid (ADF) detergent fiber obtained from cooked pinto beans. Iron binding increased with higher pH, higher iron concentration, higher fiber concentration and smaller fiber particle size. Maximum binding of iron was at pH 6.5 and minimal binding at pH 4.0 for both NDF and ADF. A 50% decrease in particle size increased iron binding by 8%. Binding of copper and zinc increased with higher copper and zinc concentrations. Both NDF and ADF had a greater affinity for copper than for either iron or zinc. Scatchard plots indicated the presence of two types of binding sites for zinc, one type for iron, and one type for copper.     

FIBER CONTENT IN THE EDIBLE PORTION OF EIGHT MANDARIN ORANGES CULTIVARS

Eight commercial varieties of mandarin oranges grown in Spain (Nova, Ortanique, Satsuma, Marisol, Fortuna, Ellendale, Clementine and ecologic Clementine) were harvested in winter and analyzed for their fiber composition. The neutral detergent fiber (NDF) content, 21.32 ± 0.09%, was higher than the crude fiber (CF) content, 15.42 ± 0.10%, and the acid detergent fiber (ADF) content, 8.59 ± 0.05%. The CF contents were in the range of 14.55–16.50%, lower than previously reported, because only the edible portion was considered in this study. The relative content of CF of the eight cultivars studied was not consistent with those of the NDF and/or ADF. Clementine had the highest values of CF, but the lowest of NDF, with intermediate values of ADF. On the other hand, the cvs. Nova and Ortanique had the lowest values of CF, but the highest values of both NDF and ADF. Therefore, the most valuable mandarin orange cultivars, according to their fiber content, were traditional and ecologic Clementine, Nova and Ortanique.     

Equation to predict feed intake response by lactating cows to factors related to the filling effect of rations

Our objective was to predict the dry matter intake (DMI) response during ration formulation to factors related to the filling effect of rations and their interaction with milk yield (MY) by lactating cows past peak lactation. A data set was developed consisting of 134 treatment means from 34 experiments reported in 32 peer-reviewed articles published from 1990 through 2015. The data set included data for cows ranging from 60 to 309 d postpartum with mean DMI ranging from 17.6 to 30.6 kg/d and MY ranging from 20.3 to 51.1 kg/d. Ration composition among treatments ranged from 12.7 to 21.8% of dry matter (DM) for crude protein, 11.5 to 31.0% of DM for acid detergent fiber (ADF), 25.5 to 48.2% of DM for neutral detergent fiber (NDF), 9.9 to 39.3% of DM for forage NDF (FNDF), and 0.45 to 0.84 for the ratio of ADF% to NDF% (ADF/NDF). Laboratory measures of digestibility of NDF (in vitro or in situ, FNDFD) for the sole or major forage ranged from 24.1 to 72.7%. The model included the random effect of study to account for various experiment-specific effects including different methods of measurement of NDF and FNDFD among studies. The full model also included linear and quadratic effects of crude protein, ADF, NDF, FNDF, ADF/NDF, and FNDFD, as well as their linear and quadratic interactions, and mean MY for each study and its interaction with ration factors. The proposed prediction equation is DMI (kg/d) = 12.0 ? 0.107 × FNDF + 8.17 × ADF/NDF + 0.0253 × FNDFD – 0.328 × (ADF/NDF – 0.602) × (FNDFD ? 48.3) + 0.225 × MY + 0.00390 × (FNDFD ? 48.3) × (MY – 33.1) with mean bias = 0.00 kg/d, root mean square error = 1.55 kg/d, and concordance correlation coefficient = 0.827. Dry matter intake was positively related to MY and ADF/NDF and negatively related to FNDF, and FNDFD was positively related to DMI for cows with high MY but negatively related to MY for cows with low MY. In addition, DMI was positively related to FNDFD for low ADF/NDF but negatively related to FNDFD for high ADF/NDF. The ADF/NDF was included to represent differences in forage fragility between grasses and legumes. The proposed model was compared with the equation recommended by the National Research Council (2001) that was developed using only animal factors by fitting each equation to a subset of the data set that included the required inputs for both. The National Research Council (2001) equation without diet factors had a higher root mean square error and over-predicted DMI at high DMI and under-predicted DMI at low DMI. Our proposed equation should be useful to predict DMI response to factors related to the filling effects of rations during ration formulation.     

Untersuchungen an Polysaccharid-, Pektin- und Ballaststoff-Fraktionen von Sanddornbeeren

The alcohol-insoluble substance (AIS) was prepared from freshly picked buckthornton berries (Hippophae rhamnoides L.) (4.70% of the fresh substance). By sequential extraction with water, ammonium oxalate, 0.05 N HC1 and 0.05 N NaOH, the following quantities of galacturonan/ 100 g AIS were obtained: 0.15 g, 0.4 g (ca.), 0.94 g, 2.29 g resp. These pectin extracts were purified as Cu²⁺ salts. After dialysis they were fractionated into a water-soluble and a water-insoluble part. In these fractions Glc, Gal and Xyl were the predominant neutral saccharide units. Ara, Rha and Man were present in smaller amounts. A higher GalA content (in g per 100 original AIS) was found in the soluble fractions (with the exception of the alkali extract). The pectins from buckthornton berries are middle-esterified and partially acetylated. The composition of the AIS was determined as 9.25% pectin, 34.8% protein and 38.9% total polysaccharides. In the residue after sequential pectin extraction (RE), which contained 60.0% of the AIS, 3.89% pectin, 12.9% protein and 28.0% total polysaccharides were found. By the enzymatic method the percentages of soluble and insoluble dietary fiber were estimated as 13.6 % and 34.1% respectively, whereas the RE contained 5.1% soluble and 34.4% insoluble fiber. The following dietary fiber fractions were determined by the detergent method for both preparations: in case of AIS 36.2% NDF, 3.0% NDF filtrate, 28.0% ADF and 9.6% lignin were found to be present, whilst in the RE, the following components were estimated: 32.8% NDF, 1.4% NDF filtrate, 26.1% ADF and 10.1% lignin. The data presented relates to 100 g original AIS. The water binding capacity was observed to decrease from 7.50 g H₂O (AIS) to 4.26 g H₂O (RE) per 1 g original AIS. For both of these preparations, more than 40 % of bound water was found in the NDF fractions and approximately 30% in the ADF fractions.

     

Changes of phosphorus and trace elements species in rye and oat flakes and oat porridge induced by simulated digestion

Fractionation of chemical species of phosphorus, manganese, iron, nickel, copper, zinc and molybdenum in rye and oat flakes and porridge made of oat flakes was studied by size exclusion chromatography coupled to inductively coupled plasma mass spectrometry. The effect of in vitro simulated digestion of the samples was elucidated by comparison of the digestates and the extracts of the samples (in the Tris–HCl buffer solution, pH = 7.5). The procedure of simulated digestion included two steps: the pepsin-catalysed hydrolysis in diluted hydrochloric acid (pH = 1.7) followed by the pancreatin-catalysed hydrolysis at pH = 7.5. The enzyme-catalysed digestion of the samples results in alteration of iron, copper and zinc species distribution. The species of phosphorus in original cereal samples are distributed between two fractions: a medium-molecular mass fraction (15 kDa) and a low-molecular mass fraction (2 kDa). This pattern is also kept basically in the sample digestates. In digested samples, the majority of soluble iron is bound in a medium-molecular mass fraction (20 kDa), while in the extracts only traces of iron were found in a high-molecular mass fraction. Approximately 90% of the soluble zinc in the digestates of cereal flakes is represented by non-bound zinc ions. The bound zinc is mostly concentrated in a low-molecular mass fraction (1–2 kDa) together with some copper and almost all nickel. The low-molecular mass fractions (1–2 kDa) of nickel, copper and zinc present in extracts of original samples correspond quite well to those in the respective digestates. Molybdenum species occurs in another low-molecular mass fraction.     

Dietary fibre and components of the nitrogen-free extract of almond kernels

Determinations of neutral and acid detergent fibre residues (NDF and ADF), hemicellulose, cellulose and lignin in almond nuts (Prunus amygdalus) were carried out. The NDF content was about 5% while the crude fibre content was only approximately 2%. The composition of several components of nitrogen-free extract (NFE) such as soluble sugars, starch, gums and mucilages and pectins were also determined, and the results are discussed.     

Storage of fresh and ensiled forages by freezing affects fibre and crude protein fractions

The effect of freezing on fibre and crude protein fractions of forages was determined. Fresh and ensiled lucerne and fresh bromegrass were processed immediately after collection or stored at ?25°C for 1 day or 1, 6 or 12 months before drying at 55°C. Samples were frozen quickly by submersion in liquid nitrogen or slowly at ?25°C. Samples which were not frozen were processed immediately or after 1 h delay at room temperature. All treatments were replicated (n = 3). Samples were analysed for crude protein (CP), trichloroacetic acid soluble CP (TSCP), phosphate buffer soluble CP (BSCP), neutral detergent insoluble CP (NDCP), acid detergent insoluble CP (ADCP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent sulphuric acid lignin (lignin) and ash. Freezing decreased BSCP and increased NDCP by more than 40% for bromegrass. Freezing also changed NDF, ADF, lignin, ash, CP and ADCP in different ways depending on forage type and length of time frozen. No significant effects were observed for method of freezing or a 1-h delay in processing. An additional experiment showed that freeze-drying resulted in less insoluble protein than ovendrying. Prior freezing of forages appeared inconsistently to change the extent of gaseous loss during drying, and resulted in precipitation of protein. These changes also affected fibre estimates. Fresh forages should not be frozen and thawed before analysis of protein or fibre fractions.     

Fecal particle dry matter and fiber distribution of heifers fed ad libitum and restricted with low and high forage quality

Wet sieving of manure can be used as a means of evaluating the nutrient utilization of diets by dairy cows. A commercially available system for this analysis (Nasco Digestion Analyzer, Nasco, Fort Atkinson, WI; NDA) employs principles of wet sieving for on-farm assessment. The objective of this study was to evaluate effects of diet manipulations and sampling techniques on fecal particle dry matter (DM), neutral detergent fiber (NDF), and starch distribution on NDA sieves. Eight Holstein heifers (means ± SD; age 18.4 ± 0.6 mo and BW 457.2 ± 27.3 kg), were randomly assigned to a split-plot 4 × 3 incomplete Latin square experimental design with 18-d periods (15 d of adaptation and 3 d of sampling). Treatment rations differed in forage quality (high ADF <35%, low ADF >35%) and fiber content (high NDF >45%, low NDF <40%) and were offered to heifers for ad libitum and restricted intakes. Diets were fed to allow 900 to 1,000 g/d of body weight gain and fed once daily. Fecal grab samples were collected 0, 6, 12, and 18 h after feeding all 3 d of the sampling period, and the remaining feces was collected in the manner of total fecal collection to represent a daily composite sample. After wet sieving of each sample using a NDA kit, the retained material on sieves was dried and analyzed for DM, NDF, and starch content. Sampling day and feeding regimen did not affect distributions of nutrients. Distributions of total fecal particle DM were greater for high forage quality and high fiber content diets (14.66 to 20.37% of sample DM). The NDF content in retained material decreased with decreasing sieve size (from 89.81 to 86.86%) and was not affected by forage quality and fiber content, whereas NDF retained on NDA (% DM) followed the same pattern as the retained particle DM weight. Starch content in retained material was below 0.5% in the majority of diets. Average retained fecal particle DM and NDF content varied depending on the time after feeding, resulting in the large differences between grab fecal samples and a daily total composite sample. However, average values of retained particle DM and NDF weight for all sampling time points were similar to ones from total daily composite sample.     

Effect of variety and crude protein content on nutrients and certain antinutrients in field peas (Pisum sativum)

Protein content was used as an indicator of environmental conditions for a study on varietal and environmental variation in proximate composition, minerals, amino acids and certain antinutrients of field peas. Four field pea varieties, each with three levels of protein content, were selected. Crude protein content overall ranged from 20.2 to 26.7%. Analysis of variance showed that both variety and environmental conditions had a significant effect on starch, acid detergent fibre (ADF), neutral detergent fibre (NDF) and fat content, but ash content was only affected by variety. Significant varietal and environmental differences in potassium (K), manganese (Mn) and phosphorus (P) were noted. Calcium (Ca) and copper (Cu) showed significant varietal differences, while iron (Fe), magnesium (Mg) and zinc (Zn) had significant environmental differences. Environmental conditions showed significant effects on alanine, glycine, isoleucine, lysine and threonine content. Variety had a significant effect on sucrose, raffinose and phytic acid content, whereas environmental conditions had an influence on trypsin inhibitor activity (TIA). The major pea components protein and starch were inversely correlated. ADF, NDF, Fe, Mg, Zn and the amino acid arginine were positively correlated with protein content. The amino acids glycine, histidine, isoleucine, lysine and threonine were negatively correlated with protein content. It was found that tryptophan was the most deficient amino acid and the sulphur‐containing amino acids were the second limiting amino acids in peas. Raffinose was positively correlated with sucrose but negatively correlated with verbascose. There were significant correlations between mineral contents and some of the proximate components. Copyright © 2004 Society of Chemical Industry     

洗涤剂法测定烟草及烟草制品中中性洗涤纤维、酸性洗涤纤维、酸性洗涤木质素的研究

为准确测定烟草及其制品中各种纤维素含量,优化了洗涤剂法的前处理条件,并定量分析了烟叶及烟草制品中中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)和酸性洗涤木质素(ADL)。结果表明:1)前处理中用苯、乙醇、乙醚混合溶剂回流4 h能除去绝大部分酯溶性的干扰物质;2)使用高温淀粉酶能够消除烟叶中淀粉对中性洗涤纤维检测带来的干扰;3)NDF、ADF、ADL检测限分别为0.26%、0.17%、0.17%,回收率为89%-101.4%;4)不同类型烟叶原料之间NDF和ADF含量的差异明显高于不同类型卷烟之间的差异;5)烟草及烟草制品的ADL含量基本都在3%以下。     

Iron solubilisation by chicken muscle protein digests

The objective of this work was to compare the solubilisation of iron by in vitro digests of soluble and insoluble protein fractions from chicken muscle. Chicken breast muscle was extracted to provide dilute salt-soluble protein (DSSP) and dilute salt-insoluble protein (DSIP) fractions. These fractions together with casein and ovalbumin were subjected to in vitro digestion in the presence of ferric iron. After proteolytic digestion, soluble iron increased fourfold for DSSP, 20-fold for DSIP, twofold for casein and 0.5-fold for ovalbumin. 64% of the soluble iron in the DSSP digest and 30% of the soluble iron in the DSIP digest were ferrous; in the casein and ovalbumin digests, less than 6% was ferrous. Dialysable iron was less than 5% of the soluble iron for all proteins and was mostly ferric iron. DSIP solubilised twice as much iron as DSSP but much less than casein or ovalbumin digests. It was concluded that muscle proteins solubilise iron by reduction and chelation to mostly large (non-dialysable) peptides resulting from digestion. © 1999 Society of Chemical Industry     

Binding of Iron by Cellulose, Lignin, Sodium Phytate and Beta-Glucan, Alone and in Combination, Under Simulated Gastrointestinal pH Conditions

Cellulose (Ce), Lignin (L), Na phytate (P) and beta-glucan (G), alone, and in combination, were evaluated as to their effect on iron profiles in model systems containing FeSO₄• 7H₂O under simulated gastrointestinal pH conditions. Both cellulose and lignin alone, were found to bind a high percentage of the iron in an insoluble form at pH 5.7±0.4 and pH 6.6±0.1, but less at pH 2.0±0.1. However, in the presence of other model components, cellulose unlike lignin had a minimal effect on total binding at all pH levels. Na phytate, alone, formed soluble complexes at all pH levels and when added to lignin led to the solubiization of some of the iron bound to lignin. Beta-glucan formed soluble iron complexes, which appeared to have a low binding strength with iron.     

Cell-Constituents,Tannin Levels by Chemical and Biological Assays and Nutritional Value of Some Legume Foliage and Straws

Twenty six straw and 15 foliage samples of Lathyrus sativus , Vicia narbonensis , V sativa and V ervilia were analysed for ash, crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), extractable phenols (Pe), extractable tannins (Te), extractable condensed tannins (CTe), protein precipitation capacity (PPC) and in vitro characteristics predicted from Hohenheim gas test. The content of crude protein in the foliage was significantly higher than that of the straws (152·6 vs 64·5 g kg⁻¹), while ash (82·8 vs 116·8 g kg⁻¹), NDF (332·7 vs 523·5 g kg⁻¹) and ADF (205·2 vs 369·9 g kg⁻¹) were significantly lower. For straws of L sativus , V narbonensis and V sativa , there was no significant difference in the protein and ADF contents, whereas ash and NDF contents were significantly lower and higher respectively in L sativus as compared to V narbonensis or V sativa . Predicted from gas volumes, the organic matter digestibility (OMD: 70 vs 56%) and metabolisable energy (ME: 9·7 vs 7·3 MJ kg⁻¹) were significantly higher for the foliage compared to straws. The OMD of L sativus straws was significantly lower compared to the straws of V narbonensis and V sativa . The OMD and ME of the straws of second year was significantly lower than those of the first year. The CP, OMD and ME of V sativa foliage were higher than that of V narbonensis . There was no difference in the cell constituents, OMD and ME of foliage samples of V sativa harvested in May 1992 and June 1992. The contents of Pe, Te and CTe of straws were 1·08%, 0·43% and 0·33%, respectively, and those of foliage were 2·27%, 1·30% and 1·63%, respectively. PPC was not detected for any of the foliage and straw samples. The results suggested that the tannin levels of legume straws investigated are negligible and those of the legume foliage are very low. This does not appear to adversely affect their nutritive value since the maximum decrease in OMD by the tannins was about 3% units.     

Chelation and reduction of iron by chicken muscle protein digests: the role of sulphhydryl groups

The role of sulphhydryls in the chelation and reduction of iron by digests of chicken muscle was investigated. The salt‐soluble (DSSP) and myofibrillar (DSIP) proteins were extracted from chicken muscle and digested with pepsin/pancreatin, and the digests were then incubated with ferric iron. The DSIP digest bound twice as much iron as the DSSP digest; about half the bound iron was ferrous. Iron binding was accompanied by a 74% drop in free sulphhydryls in the DSSP digest and a 72% drop in the DSIP digest. Modification of sulphhydryls in the digests by either oxygen, N‐ethylmaleimide or p‐chloromercuribenzoate led to a loss of ～90% in reactive sulphhydryl groups and was accompanied by losses in iron binding which averaged 79% for DSSP and 67% for DSIP. Losses in ferrous bound iron were proportional to the loss in total bound iron. It was concluded that for the muscle protein fractions, sulphhydryl residues are the principal component responsible for iron binding, but that other residues may play a minor role. © 2001 Society of Chemical Industry     

Evaluation of detergent extraction procedures for characterising carbohydrate components in ruminant feeds and digesta

Steers fitted with simple rumen and abomasal cannulas were given isoenergetic diets of approximately equal amounts of untreated (UT) barley straw and concentrates (flaked maize + tapioca) alone (BS) or with urea (BSU) or fishmeal (BSF). Similar diets were also given in which the barley straw had been treated (AT) with NaOH (BSA, BSAU and BSAF respectively). The diets were given in a 6 × 6 Latin square design. Feed components and abomasal digesta samples were analysed for neutral (NDF) and acid (ADF) detergent fibres and for monosaccharide constituents of structural polysaccharides. Hemicellulose contents were estimated as the sum of xylose + arabinose (X + A) and by the difference between ash-free NDF and ash-free ADF (NDF-ADF). Cellulose was estimated as β-linked glucose (C) and by the difference between ash-free ADF and lignin (ADF–L).¹⁰³ Ruthenium and PEG were given as flow markers and flows (g24h^?1) at the abomasum of carbohydrate components estimated in these ways were calculated. Approximately 98% (by wt.) of the cellulose (C) found in original feed and digesta samples was recovered in both NDF and ADF. Recoveries of hemicellulose (X + A) in NDF from UT straw, AT straw and abomasal digesta were approximately 92, 48 and 50%, respectively. The ADF fraction of feeds and digesta contained 3–6 and 10–17% of the nitrogen and xylose, respectively, present in the original samples. Mouth to abomasum digestibilities of hemicellulose (NDF– ADF) for diets BS, BSU, BSF, BSA, BSAU and BSAF were 39, 62, 67, 29, 61 and 76%, respectively. Corresponding values for cellulose (ADF–L) were 37, 34, 50, 45, 48, and 63%, respectively. The use of NDF–ADF and ADF–L as measures of hemicellulose and cellulose contents, respectively, of feeds and digesta, and the digestibility of these carbohydrate fractions between mouth and abomasum of steers are discussed.     

Enzymatic effects of Pleurotus ostreatus spent substrate on whole-plant corn silage and performance of lactating goats

Pleurotus ostreatus (oyster mushroom) synthesizes enzymes that degrade lignin, cellulose, and hemicellulose. The objectives of this study were to evaluate the effect of Pleurotus ostreatus spent substrate (POSS) on whole-plant corn silage (WPCS) chemical composition, antioxidant capacity, lignin monomers, and in vitro digestibility, as well as the performance of lactating goats fed corn silage treated with different levels of POSS. In experiment 1, 4 levels of lignocellulolytic enzymes were tested in a complete randomized design: 0, 10, 20, and 30 mg of lignocellulosic enzymes per kilogram of fresh matter, 4 replicates per treatment (vacuum-sealed bags). The bags were opened 60 d after ensiling. In experiment 2, corn silage treated with 3 enzyme levels (0, 10, or 30 mg/kg of fresh matter) was fed to lactating goats as part of the total mixed ration. Nine lactating Saanen goats (62.68 ± 7.62 kg BW; 44 ± 8 d in milk; 2.91 ± 0.81 kg of milk/day, mean ± SD) were assigned to three 3 × 3 Latin squares. Data were analyzed using the GLIMMIX procedure of SAS (version 9.4, SAS Institute Inc.), and means were compared by linear and quadratic orthogonal contrast. In experiment 1, neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin, and cellulose quadratically decreased in the WPCS treated with POSS. At the nadir point, POSS decreased NDF by 14.1%, ADF by 19.5%, lignin by 9.07%, and cellulose by 22.1% compared with the untreated silage. Therefore, POSS led to a quadratic increase in in vitro dry matter digestibility of WPCS (+8.88% at the vertex) compared with the untreated silage. In experiment 2, POSS quadratically increased the in vivo total-tract ADF digestibility. Also, the concentration of polyphenols in the milk of goats linearly increased with the addition of POSS, and no differences were observed among treatments for milk yield and composition. In summary, adding 10 mg of lignocellulolytic enzymes from POSS per kilogram of fresh matter of whole-plant corn at ensiling had a more evident reduction in lignin and cellulose concentration, leading to greater in vitro digestibility, as well as greater in vivo ADF digestibility; however, milk yield was not different among treatments.     

The influence of cooking technique on dietary fibre of boiled potato

Samples of twenty-five different cultivars of potatoes were prepared and examined after cooking by boiling and by pressure cooking, peeled and 'in the jacket' in a factorial design to study the effect of cooking on dietary fibre fractions of potatoes. Raw samples were prepared as control.
The samples were analysed for acid detergent fibre (ADF) and lignin by published procedures. Filtration problems were encountered with the published procedure for neutral detergent fibre (NDF) giving rise to lack of reproducibility. Reproducibility was restored by introducing a short incubation of the sample with α-amylase enzyme ( Bacillus subtilis ) prior to the normal detergent digestion.
The lignin content of all samples was < 0.25% on a dry matter basis. Both ADF and NDF increased on cooking but boiled samples did not differ from pressure cooked samples. Cooking 'in the jacket' gave higher ADF values than peeled samples but the effect was not observed for NDF values.
Cultivar differences were significant for both ADF and NDF values but as the samples were all from a single season's crop in a single field a definitive ranking is not possible.     

Effects of alfalfa hay of varying fiber fed at 35 or 50% of diet on lactation and nutrient utilization by dairy cows.

Five alfalfa hays (four from Arizona and one from California), varying in percentages of ADF (26, 28, 32, and 38%), were fed to 40 lactating Holstein cows averaging 90 DIM. Cows were in 10 groups of 4 cows each; groups were based on 14-d pretreatment milk yield. Each hay was included in TMR to provide 50 or 35% of DM. Diets were fed for ad libitum intake for 70 d. Feeding behavior of 2 cows per treatment was electronically monitored for 14 d. Total tract digestibilities of DM, ADF, and NDF were determined using Cr2O3, and ruminal in situ loss of DM, ADF, and NDF of hays was estimated using 4 cows fitted with ruminal fistulas. Dry matter intake, 3.5% FCM, changes in BW, rectal temperatures, and milk composition (except milk fat) were not affected by ADF in hays or concentrate percentage. However, milk yield decreased as ADF in hay increased, particularly at 50% concentrate. At 50% concentrate, milk yield of cows fed hays of 26 to 28% ADF averaged 30.7 kg/d, and the mean for cows fed 32 and 38% ADF hays was 27.6 kg/d. Milk fat percentages tended to be lower on higher concentrate. Eating time was longer as hay ADF increased and tended to decrease on high concentrate, but there were no significant effects of treatment on number or length of meals. In situ disappearance of DM, ADF, and NDF decreased as hay ADF increased, but total tract digestibilities of ADF and NDF were greater in hay of higher fiber content, particularly in cows fed 35% hay.(ABSTRACT TRUNCATED AT 250 WORDS)     

Composition and in vitro digestibility of raw versus cooked white‐ and colour‐flowered peas

Ten pea cultivars (four white‐flowered, Pisum sativum ssp. hortense, and six colour‐flowered, Pisum sativum ssp. arvense) grown in Latvia were analyzed and tested in in vitro experiments, as raw and cooked seeds. The colour‐flowered (CF) had a greater proportion of hulls and a higher acid detergent fibre (ADF) content than white‐flowered (WF) pea seeds (10.7 vs. 8.2% and 92.2 vs. 84.5 g/kg dry matter (DM), respectively). Three out of six CF varieties had a significantly greater amount of protein bound to neutral detergent fibre (NDF) than WF peas. The tannin content was higher in CF than in WF peas (8.46 vs. 0.37 g/kg DM). In vitro protein and amino acid digestibility was about 8% higher in WF than in CF varieties. Cooking decreased the tannin content in CF peas (8.46 vs. 5.51 g/kg DM) but had no effect on in vitro protein digestibility. Heat treatment reduced significantly trypsin inhibitor activity and amount of protein bound to NDF in CF and WF varieties (from 6.50 to 0.52 and from 6.54 to 0.46 trypsin inhibitor units (TIU)/mg DM; from 1.250 to 0.831 and 0.761 to 0.209 g N/100 g NDF, respectively). However, the protein bound to NDF content in pea DM increased in CF and decreased in WF varieties (from 1.525 to 2.145 and from 0.913 to 0.502 g N/kg DM, respectively). Cooking resulted in an increased NDF content over two times in both CF and WF pea seeds (from 122 to 259 and from 120 to 262 g/kg DM, respectively). The results suggest that colour‐flowered pea may be considered as an interesting dietary alternative to white‐flowered pea since cooking removes trypsin inhibitor activity (TIA), decreases tannins, and increases dietary fibre contents.