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The botanical and chemical composition of diets consumed by ruminants is different from the composition of plant species available in the rangeland or pastures on which they graze. Exploring alternative and improving existing methods of estimating botanical composition (diet selection) is imperative in advancing sustainable feeding practices in extensive production systems. The ability to predict the intake and digestibility of the diet consumed is important in designing grazing management for different feeding systems as well as supplementation strategies. This facilitates the efficient use of feed resources for optimal animal performance. This review assesses the merits, limitations, and potential advancements in techniques used to estimate botanical composition, forage intake, and digestibility in ruminants. Supplements containing sufficient quantity and identifiable n-alkanes can be used to determine the total forage intake in grazing ruminants without dosing the animals with synthetic even-numbered n-alkanes. When the botanical composition, intake, and digestibility of diet are estimated using internal markers, the results should be validated with those of faecal near-infrared reflectance spectroscopy (NIRS) or plant cuticular compounds to enhance the prediction accuracy. This should be done to determine the degree of error in the use of internal markers. Conclusively, the use of internal markers with automated solver routine software is a prudent approach to predicting botanical composition due to the analytical ease of the markers involved and the associated model assumptions. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate acid detergent lignin (ADL), and amylase-treated ashcorrected undigestible neutral detergent fiber after 240 h of ruminal in vitro incubation (uNDF), and near infrared spectroscopy (NIRS) scanning of feces as methods to estimate the digestibility of diets varying in forage quantity and quality when fed to beef cattle. Five total collection (TC) digestibility studies examined 17 different diets and provided individual fecal samples and the corresponding apparent total tract digestibility of nutrients (n = 229). Feed, orts, and fecal samples were analyzed for dry matter (DM), organic matter (OM), nitrogen (N), amylase-treated ash-corrected neutral detergent fiber (aNDFom), acid detergent fiber (ADF), ADL, and uNDF. Previously developed fecal NIRS digestibility calibrations were expanded with dried and ground samples using a FOSS D3F scanning monochromator (FOSS, Eden Prairie, MN). Marker estimated and NIRS predicted nutrient digestibility coefficients were regressed against those determined by TC and goodness-of-fit statistics were applied. Mean concentrations of ADL and uNDF in diets ranged from 23.4 to 96.4 g/kg DM and 67.7 to 200 g/kg DM, respectively, with mean fecal recoveries of 94.2% (SD ± 15.7%) for ADL and 87.5% (SD ± 11.1%) for uNDF. Regression fit statistics between NIRS and TC were not different from one (P > 0.05), with R² > 0.83 except for ADF digestibility (R2 = 0.63). In comparison, regression statistics between internal markers and TC were poorer with R² ranging from 0.21 to 0.78. Concordance correlation coefficients (CCC) between NIRS and TC were greater than 0.90 for DM, OM, N, and aNDFom digestibility, and 0.77 for ADF digestibility. The CCC between ADL and TC ranged between 0.63 and 0.82, and between uNDF and TC from 0.26 to 0.78. Correction bias (Cb) was high for all parameters (Cb > 0.76) except for ADF digestibility (Cb = 0.58) as estimated by uNDF. The mean square error of prediction (MSEP) for NIRS predicted digestibility were lower (< 10.7%) than those estimated by internal markers, and most of the error was attributed to random bias (> 97.9%). Random bias for ADL was also greater (>76.1%); however, for uNDF the error was more evenly partitioned into mean bias (46.4% to 49.4%) and random bias (30.4 to 41.9%). Digestibility predictions from NIRS scanning of feces were more accurate and precise than when estimated using the internal markers ADL and uNDF. In the absence of NIRS, ADL estimations appear to be more precise and accurate than uNDF for forage-based diets, with uNDF possibly of greater value for estimating the digestibility of high concentrate diets. [ABSTRACT FROM AUTHOR]

Mammography is a very useful tool to diagnose breast cancer in early stages when it is easier to treat. There are two types of evidence that radiologists look for in a mammogram, calcifications and the existence of masses. In this study, an intelligent computer‐aided diagnosis system is proposed for the detection of masses in mammographic images regardless of their nature. The proposed method uses a combination of extended maxima transformations, having different threshold values, in order to find suitable internal and external markers for a marker‐based watershed segmentation. After segmentation, a two‐stage classifier is used to distinguish the masses better from the healthy breast tissue. A feature vector based mainly on contrast and texture features is calculated and two alternative approaches, a Bayesian classifier and a support vector machine (SVM) with Gaussian kernel function, are implemented for further reduction of the false positive areas. The system was evaluated using the data from two online databases. Specifically, 73 mammographic images from the new curated breast imaging subset of digital database for screening mammography (CBIS‐DDSM) database and all the mammographic images that contain masses from the mini‐mammographic image analysis society (MIAS) database were used. The overall sensitivity, in both datasets, was near 80% when the Bayesian classifier was used and above 85% when the SVM was applied. [ABSTRACT FROM AUTHOR]

Reliable assessments of indigestible dietary components are required when using internal markers to estimate diet digestibility and determine the potentially digestible portion of the fiber. The lack of a standardized methodology and understanding of how antinutritional factors influence indigestible residues can result in erroneous estimates with inconsistent variation across trials and among studies. Previous studies have detailed suitable bag porosity and sample size (SS) with incubation length (IL) varying from 96 to 504 h, with many assuming that 288-h IL yields truly indigestible components. Recent studies have primarily investigated the variation that exists among feedstuffs, but most have failed to account for possible effects of secondary compounds. Using 2 similar concentrate diets, one of which contained supplemental condensed tannins (CT), we investigated the effect of bag type (BT ; 10 and 25 μm), SS (20 and 40 mg/cm2), and IL (288 and 576 h) on in situ indigestible DM (iDM) and neutral detergent fiber (iNDF) residues of feed and feces, and resultant DM and NDF digestibilities. There were no 3-way interactions (P > 0.05), but 2-way interactions were present for iDM and iNDF residues with BT × SS influencing the control (no CT) ration (P < 0.01), SS × IL impacting feed containing CT (P < 0.01), and BT × IL affecting both feedstuffs (P ≤ 0.01). For the control diet, only BT × SS affected DM and NDF digestibilities. Whereas the CT diet did not demonstrate any significant interactions for digestibilities. Values of iDM were largely influenced by contamination that varied greatly based on intrinsic factors associated with the bag and incubation duration. The presence of CT influenced iDM and iNDF to varying degrees due to possible trapping of CT–substrate complexes. For the control diet, the use of 25-μm bags resulted in lower fecal recoveries relative to the 10 μm (P < 0.01). However, there appears to be a dynamic relationship among BT, SS, and IL within respective diets and sample types that can affect indigestible components and resultant digestibility estimates. Based on simulations from these data, the sample size required to attain 90% power when utilizing 2 incubation animals exceeds the triplicate and quadruplicate replications commonly utilized. Further emphasizing the necessity for a more complete understanding of incubation dynamics to design biologically and statistically valid investigations. [ABSTRACT FROM AUTHOR]

Highlights • Water-soluble carbohydrates were apparently digested up to approximately 80% by the time reaching the end of the stomach. • Compartmental apparent digestibility of nutrients was well estimated by 4 N acid insoluble ash and plant alkanes compared with other markers. • Plant alkanes are best suited to estimate apparent digestibility of fiber in diets for horses. • Estimations of apparent digestibility by external markers (Cr 2 O 3 or TiO 2) were accurate only for the total tract. Abstract Partitioning of apparent digestibility is helpful to assess the nutritive value of feedstuffs and to identify possible risks for digestive disorders. In horses, information on partial digestibility is less available and address less on carbohydrate fractions. It is suggested that large parts of water-soluble carbohydrates (WSC) are degraded already in the stomach, which elevates the risk for mucosal ulceration. Our objective was to investigate apparent digestibility of dry matter (DM), proximate nutrients, and WSC along the digestive tract using internal and external markers. Twelve adult horses were adapted for 20 d to meadow hay (1.5 kg/100 kg body weight per day) and crushed oats (1.2 g starch/kg body weight per day), which were offered 2 times a day. Six horses on the treatment group also received 0.15 g of fructooligosaccharides + inulin (via Jerusalem artichoke meal) per kg body weight per day. The other 6 horses on the control group received corncob meal without grains. The tested markers were 4 N acid insoluble ash (AIA), acid detergent lignin (ADL), n -heptacosane, n -nonacosane, n -hentriacontane, and n -tritriacontane. Additionally, Cr 2 O 3 (approximately 2.8 g/bolus) and TiO 2 (approximately 2.5 g/bolus) were provided as a bolus 2 times a day. The horses were euthanized at d 21 approximately 1 h after the morning meal. Samples of digesta were collected from the stomach (pars nonglandularis and pars glandularis), cecum, ventral and dorsal colon ascendens, and colon transversum. Feces were sampled at 5 d ante mortem. Compartmental and total tract apparent digestibility was calculated for each horse. The stomach seemed to be considerably involved in nutrient degradation with particular great disappearance of simple sugars, starch, and fructans (apparent digestibility was up to 78, 74, and 56%). No WSC were measured in the cecum. In the hindgut, apparent digestibility increased from the cecum to the colon transversum (e.g., for DM: 0.49–0.79 with AIA, and 0.44–0.56 with n -tritriacontane; for crude protein: 0.51–0.82 with AIA, and 0.47–0.63 with n -tritriacontane; and for neutral detergent fiber: 0.43–0.76 with AIA, and 0.37–0.50 with n -tritriacontane; P < 0.05). Supplying of fructooligosaccharides and inulin had no effect on apparent digestibility. Differences among apparent digestibility estimates did mainly belong to the gut compartments (P < 0.05) and the markers (P < 0.001). For all nutrients, apparent digestibility estimates did differ less among the plant alkanes, but they had a vast variation among the horses when based on Cr 2 O 3 or TiO 2. The extensive disappearance of WSC, including starch, in the stomach should be considered for dietary composition and risk assessment concerning stomach ulceration. Parts of WSC possibly had not been degraded in the stomach, but rapidly flowed with the liquid phase into the intestine. The probable underestimation of apparent digestibility by ADL confirms the known instability of ADL during the digestive process. Acid insoluble ash probably overestimated apparent digestibility along the hindgut, especially for the fiber fractions. Thus, apparent digestibility seemed to be best estimated by cell wall-associated plant alkanes. The estimations made by Cr 2 O 3 and TiO 2 were only accurate for the total tract, considering mealtime feeding of mixed diets. [ABSTRACT FROM AUTHOR]

The aim of this research is to compare indigestible internal markers acid insoluble ash (AIA) and acid detergent lignin (ADL) and total collection of faeces (TCF) for apparent digestibility estimation in Caspian horse. Analyses were carried out on wheat straw, alfalfa, barley and maize, for dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF) and acid detergent fiber (ADF). Using change over design including 4 ration diet, 4 period and each period was 12 days with 4 Caspian horse with 3-5 years age and reared in individual cages. The results digestibility of DM, OM, NDF, ADF did not show any significant differences among the ADL, AIA and total collection of faeces methods, but digestibility of CP and EE were significantly higher than the ADL and AIA methods. A weak correlation was found between total collection techniques and AIA, for crude fat (EE) and ADF, whereas there was a high correlation (R2=0.89) between AIA and total collection of faeces for the digestibility of crude protein. The results obtained in this study show that there were no significant difference between internal markers (acid-insoluble ash and acid detergent lignin) and total collection techniques of faeces for estimation apparent digestibility of nutrients in Caspian horses. [ABSTRACT FROM AUTHOR]

Background: The effect of time of fecal sampling on the accuracy of acid-detergent insoluble ash (ADIA) and alkaline-peroxide lignin (APL) for the prediction of fecal output (FO) in cattle was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 bermudagrass [Cynodon dactylon (L.) Pers.] hay diets markedly different in crude protein concentration (79-164 g/kg) with 2 replicates per diet for 3 periods. Cows were offered hay individually at 20 g DM/kg of body weight daily in equal feedings at 08:00 and 16:00 h for a 10-d adaptation period followed by 5-d of total fecal collection. Fecal grab samples also were taken each day during the fecal collection period at 06:00, 12:00, 18:00, and 24:00 h either directly from the rectum or from freshly voided feces. Samples were composited within cow and time across the 5 d total fecal collection period. Additionally, forage, ort, and fecal samples were analyzed for concentrations of APL and ADIA. Results: Fecal concentrations of ADIA and APL were not affected by sampling time (P = 0.22), even though diet affected (P < 0.01) fecal ADIA and APL concentrations. There were no diet × sampling time interactions (P = 0.60). Estimates of FO and dry matter digestibility (DMD) from ADIA and APL were not affected (P = 0.16) by sampling time or the diet × sampling time interaction (P = 0.74). Estimates of FO and DMD from markers from different sampling times or all different combinations of sampling time were not different (P = 0.72) from those of total collection among internal markers. Conclusion: Little variation in concentrations of ADIA and APL in daily fecal excretion across time increases flexibility in fecal grab sampling schedules for predicting FO and DMD. [ABSTRACT FROM AUTHOR]

Summary Estimation of herbage intake is a challenge both under practical and experimental conditions. The aim of this study was to estimate herbage intake with different methods for cows grazing 7 h daily on either spring or autumn pastures. In order to generate variation between cows, the 20 cows per season were either allocated to low or high stocking rate. At low stocking rate, there were 6.7 and 3.5 cows per hectare during spring and autumn, respectively, and at high stocking rate, there were 8.8 and 4.6 cows per hectare during spring and autumn, respectively. The experiment lasted 16 days in each season, and the herbage intake was estimated twice during each season. Cows were on pasture from 8:00 until 15:00, and were subsequently housed inside and fed a mixed ration (MR) based on maize silage ad libitum . Herbage intake was estimated with nine different methods: (1) animal performance (2) intake capacity, (3) content of 13 C in faeces and diet, (4) 13 C in faeces and diet, and with assumption of 13 C discrimination in the digestive tract, (5) 13 C in faeces and diet, with assumption of 13 C discrimination and in combination with in vitro organic matter digestibility (IVOM), (6) simultaneous use of two internal markers (ingestible neutral detergent fibre (INDF) and acid detergent lignin (ADL)), (7) titanium oxide in combination with IVOM, (8) titanium oxide in combination with INDF and (9) titanium oxide in combination with ADL. Furthermore, grazing time of the individual cows was recorded. The estimated average herbage dry matter intake (DMI) varied from 2.2 kg for the method using the INDF:ADL ratio to 7.6 for the methods using 13 C and intake capacity. There was a low correlation between the different methods. Dry matter intake of herbage was not affected by stocking rate except for the method using titanium oxide and ADL as markers. Milk yield was not affected by stocking rate either. It was concluded that methods based on animal performance, 13 C including discrimination factor or in combination with IVOM as well as methods based on titanium oxide gave similar estimates of the average herbage DMI intake during grazing in systems with indoor concentrate and forage feeding during night. [ABSTRACT FROM AUTHOR]

Abstract: Background and purpose: Positional uncertainties related to the set-up of the prostate, using internal markers and either 2D–2D or 3D images, were studied. Set-up using direct prostate localization on CBCT scans is compared to set-up using internal markers. Material and methods: 20 patients with prostate cancer were enrolled in the study. After each daily session, a set of 2D–2D and 3D images were acquired. The images isocenter was compared to reference images isocenter. For the set-up error analysis the systematic error, μ, and the set-up uncertainties, Σ and σ, were determined for the translational shift in the three directions, lat, lng and vrt. The set-up errors and uncertainties were calculated in the same way for rotations around the three axes, lat, lng and vrt. Results: Set-up uncertainties were evaluated for four different set-up methods. The systematic error uncertainties were found to be in the range 0.38–1.14mm and for the random error 0.79–1.48mm. For rotations the uncertainties ranges were 0.38–1.59° and 0.91–2.18° for systematic and random uncertainties, respectively. Set-up uncertainties, using internal markers or prostate itself to position the target in the isocenter, were comparable. The correlation between the two methods was better for translational shifts of the isocenter than for rotational shifts. Conclusions: The study shows that the precision of the 2D–2D set-up is equivalent to the precision of the 3D images. It also shows that the soft-tissue based set-up needs 1mm larger set-up margins than the marker based set-up for the prostate patients, when CBCT is used for daily verification of the location of the prostate. [Copyright &y& Elsevier]

• Comparison of grain boundary sliding effect on surface and body of the samples. • Development of internal markers located in grain body before superplastic deformation. • Decreased grain boundary sliding in AA5083 alloy as compared to AA7475 alloy. The grain boundary sliding as a main mechanism of superplastic deformation is typically studying by the microstructural analysis of the samples with surface markers. It is important to compare the effects related to the deformation mechanisms on the surface and in the body of the samples. Present study investigates the microstructural evolution of the samples of Al-Zn-Mg-Cu (AA7574) and Al-Mg-Mn (AA5083) alloys with both surface FIB-grids and internal Al 3 Ni-particles markers at superplastic deformation. The grain switching and grain rotation effects are found on the surface and in the body of both the studied alloys. The results, based on both surface and internal markers, suggest the decreased role of the grain boundary sliding in AA5083 alloy as compare with AA7475 alloy. [ABSTRACT FROM AUTHOR]