Prediction of key milk biomarkers in dairy cows through milk mid-infrared spectra and international collaborations.

At the individual cow level, suboptimum fertility, mastitis, negative energy balance, and ketosis are major issues in dairy farming. These problems are widespread on dairy farms and have an important economic impact. The objectives of this study were (1) to assess the potential of milk mid-infrared (MIR) spectra to predict key biomarkers of energy deficit (citrate, isocitrate, glucose-6 phosphate [glucose-6P], free glucose), ketosis (ß-hydroxybutyrate [BHB] and acetone), mastitis (N-acetyl-ß-d-glucosaminidase activity [NAGase] and lactate dehydrogenase), and fertility (progesterone); (2) to test alternative methodologies to partial least squares (PLS) regression to better account for the specific asymmetric distribution of the biomarkers; and (3) to create robust models by merging large datasets from 5 international or national projects. Benefiting from this international collaboration, the dataset comprised a total of 9,143 milk samples from 3,758 cows located in 589 herds across 10 countries and represented 7 breeds. The samples were analyzed by reference chemistry for biomarker contents, whereas the MIR analyses were performed on 30 instruments from different models and brands, with spectra harmonized into a common format. Four quantitative methodologies were evaluated to address the strongly skewed distribution of some biomarkers. Partial least squares regression was used as the reference basis, and compared with a random modification of distribution associated with PLS (random-downsampling-PLS), an optimized modification of distribution associated with PLS (KennardStone-downsampling-PLS), and support vector machine (SVM). When the ability of MIR to predict biomarkers was too low for quantification, different qualitative methodologies were tested to discriminate low versus high values of biomarkers. For each biomarker, 20% of the herds were randomly removed within all countries to be used as the validation dataset. The remaining 80% of herds were used as the calibration dataset. In calibration, the 3 alternative methodologies outperform the PLS performances for the majority of biomarkers. However, in the external herd validation, PLS provided the best results for isocitrate, glucose-6P, free glucose, and lactate dehydrogenase (coefficient of determination in external herd validation [R2v] = 0.48, 0.58, 0.28, and 0.24, respectively). For other molecules, PLS-random-downsampling and PLS-KennardStone-downsampling outperformed PLS in the majority of cases, but the best results were provided by SVM for citrate, BHB, acetone, NAGase, and progesterone (R2v = 0.94, 0.58, 0.76, 0.68, and 0.15, respectively). Hence, PLS and SVM based on the entire dataset provided the best results for normal and skewed distributions, respectively. Complementary to the quantitative methods, the qualitative discriminant models enabled the discrimination of high and low values for BHB, acetone, and NAGase with a global accuracy around 90%, and glucose-6P with an accuracy of 83%. In conclusion, MIR spectra of milk can enable quantitative screening of citrate as a biomarker of energy deficit and discrimination of low and high values of BHB, acetone, and NAGase, as biomarkers of ketosis and mastitis. Finally, progesterone could not be predicted with sufficient accuracy from milk MIR spectra to be further considered. Consequently, MIR spectrometry can bring valuable information regarding the occurrence of energy deficit, ketosis, and mastitis in dairy cows, which in turn have major influences on their fertility and survival.

Development of a subacute ruminal acidosis risk score and its prediction using milk mid-infrared spectra in early-lactation cows.

A routine monitoring for subacute ruminal acidosis (SARA) on the individual level could support the minimization of economic losses and the ensuring of animal welfare in dairy cows. The objectives of this study were (1) to develop a SARA risk score (SRS) by combining information from different data acquisition systems to generate an integrative indicator trait, (2) the investigation of associations of the SRS with feed analysis data, blood characteristics, performance data, and milk composition, including the fatty acid (FA) profile, (3) the development of a milk mid-infrared (MIR) spectra-based prediction equation for this novel reference trait SRS, and (4) its application to an external data set consisting of MIR data of test day records to investigate the association between the MIR-based predictions of the SRS and the milk FA profile. The primary data set, which was used for the objectives (1) to (3), consisted of data collected from 10 commercial farms with a total of 100 Holstein cows in early lactation. The data comprised barn climate parameters, pH and temperature logging from intrareticular measurement boluses, as well as jaw movement and locomotion behavior recordings of noseband-sensor halters and pedometers. Further sampling and data collection included feed samples, blood samples, milk performance, and milk samples, whereof the latter were used to get the milk MIR spectra and to estimate the main milk components, the milk FA profile, and the lactoferrin content. Because all measurements were characterized by different temporal resolutions, the data preparation consisted of an aggregation into values on a daily basis and merging it into one data set. For the development of the SRS, a total of 7 traits were selected, which were derived from measurements of pH and temperature in the reticulum, chewing behavior, and milk yield. After adjustment for fixed effects and standardization, these 7 traits were combined into the SRS using a linear combination and directional weights based on current knowledge derived from literature studies. The secondary data set was used for objective (4) and consisted of test day records of the entire herds, including performance data, milk MIR spectra and MIR-predicted FA. At farm level, it could be shown that diets with higher proportions of concentrated feed resulted in both lower daily mean pH and higher SRS values. On the individual level, an increased SRS could be associated with a modified FA profile (e.g., lower levels of short- and medium-chain FA, higher levels of C17:0, odd- and branched-chain FA). Furthermore, a milk MIR-based partial least squares regression model with a moderate predictability was established for the SRS. This work provides the basis for the development of routine SARA monitoring and demonstrates the high potential of milk composition-based assessment of the health status of lactating cows.

Modeling reticular and ventral ruminal pH of lactating dairy cows using ingestion and rumination behavior.

The prevention and control of metabolic and digestive diseases is an enormous challenge in dairy farming. Subacute ruminal acidosis (SARA) is assumed to be the most severe feed-related disorder and it impairs both animal health and economic efficiency. Currently, ruminal pH as well as variables derived from the daily pH curve are the main indicators for SARA. The objective of this study was to explain the daily pH course in the ventral rumen and reticulum of dairy cows using ingestion pattern and rumination behavior data gathered by automated data recording systems. The data of 13 ruminally fistulated lactating cows were collected at the experimental station of the Friedrich-Loeffler-Institut (Brunswick, Germany). The data included continuous pH measurements, which were recorded simultaneously in the reticulum by pH-measuring boluses and in the ventral rumen by a separate data logger. In addition, rumination behavior was measured using jaw movement sensors, and feed and water intakes were recorded by transponder-assisted systems. Milk yield and body weight were determined during and after each milking, respectively. For statistical evaluation, the data were analyzed using time-series modeling with multiple linear mixed regressions. Before applying the developed mathematical statistical modeling, we performed a plausibility assessment to ensure data quality. The major part of the mathematical statistical modeling consisted of data preparation, where all variables were transformed into a uniform 1-min resolution. Signal transformations were used to model individual feed and water intakes as well as rumination behavior events over time. Our results indicated that diurnal pH curves of both the reticulum and ventral rumen could be predicted by the transformed feed and water intake rates. Rumination events were associated with a marginal temporal increase in pH. We observed that the pH of the ventral rumen was delayed by approximately 37 min compared with that of the reticulum, which was therefore considered in the modeling. With the models developed in this study, 67.0% of the variance of the reticular pH curves and 37.8% of the variance of the ruminal pH curves could be explained by fixed effects. We deduced that the diurnal pH course is, to a large extent, associated with the animal's individual feed intake and rumination behavior.

Statistical modeling of ruminal pH parameters from dairy cows based on a meta-analysis.

Adequate feeding of high-performance dairy cows is extremely important to avoid the digestive disorder subacute ruminal acidosis. Subacute ruminal acidosis is defined as a status with a below-average ruminal pH that does not cause direct clinical symptoms at the individual level but is relevant for animal welfare due to a higher risk of secondary health problems at the herd level. The main objective of this study was to apply meta-analytical methods in an exploratory approach to investigate the association between pH parameters of the ventral rumen with milk and diet parameters. Data from 32 studies using continuous pH measurement in the ventral rumen of lactating cows were included in the meta-analysis. Available information extracted from all studies was categorized into parameters associated with management, cow, diet, milk, and pH. The statistical analysis was divided into 4 sections. First, a multiple imputation procedure based on a principal component model was applied, since approximately 19% of the data set consisted of missing values due to heterogeneity in provided information between the studies included in the analysis. In a second step, all potential predictors for the pH parameters, including the daily mean pH, the time with a pH below 5.8, and the pH range, were examined for their prediction suitability using multi-level mixed effects meta-regression models. These analyses were performed on the raw and the imputed data. Because the results of both approaches were consistent, the imputing procedure was considered to be appropriate. Third, automated variable selection was applied to all 3 pH parameters separately for the predictor groups milk and diet using the imputed data set. Thereby, multi-model inference was used to estimate the relative importance of the selected variables. Finally, a functional relationship between the 3 pH parameters was established. The fat to protein ratio of milk, milk fat, and milk protein showed significant associations in meta-regression analysis for all 3 pH parameters when used as a single predictor. Out of the group of diet-specific variables, the acid detergent fiber, neutral detergent fiber, nonfiber carbohydrate, starch content, as well as the forage to concentrate ratio, showed the highest significance in the models. In particular, the multi-model inference showed that the protein, fat, and lactose content of the milk can best quantify the association to the daily mean pH and the time with a pH below 5.8 in a multiple regression model.

Wire-frame integrity of patch-like Gore devices following atrial septal defect closure.

OBJECTIVES: To assess the structural integrity of the patch-like Gore Septal Occluder (GSO) used for device closure of secundum-type atrial septal defects (ASD II) in pediatric patients. BACKGROUND: GSO has shown to be effective and safe for ASD device closure in children and adolescents. METHODS: Single-center, retrospective mid- to long-term follow-up of all children and adolescents with a GSO in situ (≥12 months). Periprocedural data and follow-up data were evaluated, including chest X-rays to assess the GSO's wire-frame morphology. RESULTS: Ninety-one consecutive patients were enrolled with a median age and weight of 5 years (range 2-18) and 20 kg (range 11-95) at implantation. ASD anatomy included 64 single and 27 multi-fenestrated defects, with 39 patients having small retro-aortic rims (≤4 mm). Median follow-up period was 42.5 months (range 12-74). Chest X-rays were available in 80 children: in 74 of them, the GSO's visualization on X-ray enabled us to reliably assess the wire-frame structure. Wire-frame fracture (WFF) was ultimately detected in five of the 74 patients (6.8%); however, those occluders appeared stably anchored and well aligned to both sides of the septum, and no free wire fragments had escaped the GSO matrix. Thus, no further treatment was required. CONCLUSIONS: Our data confirm that the GSO is safe and effective for ASD closure. Despite its lightweight construction, the GSO seems to offer reliable mechanical durability. Wire-frame fractures occur, but the free wire-ends appear to have remained stable within the GSO matrix without any clinical sequelae so far.

Understanding the adoption and use of point-of-care tests in Dutch general practices using multi-criteria decision analysis.

BACKGROUND: The increasing number of available point-of-care (POC) tests challenges clinicians regarding decisions on which tests to use, how to efficiently use them, and how to interpret the results. Although POC tests may offer benefits in terms of low turn-around-time, improved patient's satisfaction, and health outcomes, only few are actually used in clinical practice. Therefore, this study aims to identify which criteria are, in general, important in the decision to implement a POC test, and to determine their weight. Two POC tests available for use in Dutch general practices (i.e. the C-reactive protein (CRP) test and the glycated haemoglobin (HbA1c) test) serve as case studies. The information obtained from this study can be used to guide POC test development and their introduction in clinical practice. METHODS: Relevant criteria were identified based on a literature review and semi-structured interviews with twelve experts in the field. Subsequently, the criteria were clustered in four groups (i.e. user, organization, clinical value, and socio-political context) and the relative importance of each criterion was determined by calculating geometric means as implemented in the Analytic Hierarchy Process. Of these twelve experts, ten participated in a facilitated group session, in which their priorities regarding both POC tests (compared to central laboratory testing) were elicited. RESULTS: Of 20 criteria in four clusters, the test's clinical utility, its technical performance, and risks (associated with the treatment decision based on the test result) were considered most important for using a POC test, with relative weights of 22.2, 12.6 and 8.5%, respectively. Overall, the experts preferred the POC CRP test over its laboratory equivalent, whereas they did not prefer the POC HbA1c test. This difference was mainly explained by their strong preference for the POC CRP test with regard to the subcriterion 'clinical utility'. CONCLUSIONS: The list of identified criteria, and the insights in their relative impact on successful implementation of POC tests, may facilitate implementation and use of existing POC tests in clinical practice. In addition, having experts score new POC tests on these criteria, provides developers with specific recommendations on how to increase the probability of successful implementation and use.

Reactions to saline drinking water in Boer goats in a free-choice system.

Salinization of groundwater and soil is a prevalent global issue with serious consequences on animal health and production. The present study was conducted to investigate the capacity of Boer goats to adjust their salt intake from saline drinking water in a free-choice system. In total, 12 non-pregnant Boer goats aged between 1 and 8 years with an average BW of 46.4±8.3 kg were kept in individual pens for 4 weeks. In the control phase (1 week), only fresh water was supplied in five identical buckets for each pen. During the subsequent treatment phase (3 weeks), fresh water and four different concentrations (0.75, 1.0, 1.25 and 1.5% NaCl) of saline water were offered simultaneously in a free-choice system. The positions of the concentrations were changed daily at random. Cut hay and water were provided ad libitum, and a mineral supplement was allocated. Feed and water intake, mineral supplement intake, ambient temperature and relative humidity were recorded daily, whereas BW and body condition score were measured weekly. Dry matter intake, total water intake and total sodium intake were significantly (P<0.001) higher during the treatment phase. Body weight and body condition were not affected by saline water intake. Across the treatment phase, saline water consumption was significantly (P<0.001) lower in young (19.6±27.1 g/kg BW0.82 per day) than in adult goats (27.9±31.5 g/kg BW0.82 per day), indicating that young goats were more sensitive towards the saline water. All goats had a significant preference for fresh water (0% salt) over saline water. At the first offering of the simultaneous choice situation (week 2), animals did not differentiate between the salt concentration of 0.75% and 1.0%. However, with successive treatment (weeks 3 and 4), animals distinguished between saline water concentrations and preferred the 0.75% salt concentration. Salt concentrations of 1% to 1.5% were avoided. The total sodium intake of the goats ranged between 0.37 and 0.55 g /kg BW0.75 per day during the treatment phase, being 8- to 11-fold higher than the daily requirements of sodium for body maintenance. The results suggest that goats are able to differentiate between saline water concentrations and to adjust their sodium intake by quick adjustments in self-selection in a free-choice system. Compared with two-choice preference tests, the present free-choice situation allows evaluating changes in saline water acceptance with prolonged exposure.

Hallux valgus and metatarsus adductus measurements: inter-reader reliability and correlations on radiographs and MRI.

AIM: To assess inter-reader reliability of metatarsus adductus (MA) using the traditional method and Engel's angle (EA) on radiography and magnetic resonance imaging (MRI) and assess correlations with hallux valgus (HV). METHODS AND MATERIALS: Ninety consecutive patients with radiographs and MRI of the foot were included. Two readers measured HV angle (HVA), traditional metatarsus adductus angle (MAA), and EA on radiographs and HVA and EA on MRI. Three- and two-way mixed model analyses were used for reader agreements. Ninety-five percent bootstrap confidence intervals were calculated. The linear mixed model was used for association between HVA and EA/MAA. RESULTS: Mean age and male to female ratio was 54.2±15.4 and 0.4:1, respectively. Mean HVA and EA were 20.6±9.4 and 21.2±8, 21.2±8.3 and 22.4±7.5 on radiographs and MRI, respectively. Mean MAA was 18.5±5.7 on radiographs. Inter-reader agreement was good for EA (ICC=0.73, 0.6) and moderate for MAA (ICC=0.41). Positive correlations between HVA, MAA, and EA on radiographs and MRI were found, but none were statistically significant (p=0.44 and 0.87). CONCLUSION: Engel's angle is more reproducible. Although positive correlations exist between the degrees of HV and MA, they are not statistically significant.

Interrelations between the rumen microbiota and production, behavioral, rumen fermentation, metabolic, and immunological attributes of dairy cows.

Different studies have shown a strong correlation between the rumen microbiome and a range of production traits (e.g., feed efficiency, milk yield and components) in dairy cows. Underlying dynamics concerning cause and effect are, however, still widely unknown and warrant further investigation. The aim of the current study was to describe possible functional interrelations and pathways using a large set of variables describing the production, the metabolic and immunological state, as well as the rumen microbiome and fermentation characteristics of dairy cows in early lactation (n = 36, 56 ± 3 d in milk). It was further hypothesized that the feed intake-associated behavior may influence the ruminal fermentation pattern, and a set of variables describing these individual animal attributes was included. Principal component analysis as well as Spearman's rank correlations were conducted including a total of 265 variables. The attained plots describe several well-known associations between metabolic, immunological, and production traits. Main drivers of variance within the data set included milk production and efficiency as well as rumen fermentation and microbiome diversity attributes, whereas behavioral, metabolic, and immunological variables did not exhibit any strong interrelations with the other variables. The previously well-documented strong correlation of production traits with distinct prokaryote groups was confirmed. This mainly included a negative correlation of operational taxonomic units ascribed to the Prevotella genus with milk and fat yield and feed efficiency. A central role of the animals' feed intake behavior in this context could not be affirmed. Furthermore, different methodological and interpretability aspects concerning the microbiome analysis by 16S rRNA gene sequencing, such as the discrepancy between taxonomic classification and functional communality, as well as the comparability with other studies, are discussed. We concluded that, to further investigate the driving force that causes the difference between efficient and inefficient animals, studies including more sophisticated methods to describe phenotypical traits of the host (e.g., rumen physiology, metabolic and genetic aspects) as well as the rumen microbiome (e.g., metagenome, metatranscriptome, metaproteome, and metabolome analysis) are needed.

Urine sodium concentrations are predictive of hypoadrenocorticism in hyponatraemic dogs: a retrospective pilot study.

OBJECTIVES: To determine if a urine sodium concentration could be used to rule out hypoadrenocorticism in hyponatraemic dogs. MATERIALS AND METHODS: Medical records were reviewed for hyponatraemic dogs (serum sodium<135 mmol/L) that had recorded urine sodium concentrations. Twenty hyponatraemic dogs were included: 11 diagnosed with classical hypoadrenocorticism and nine with non-adrenal causes of hyponatraemia. A Wilcoxon rank-sum test was used to compare results between groups. RESULTS: No dog with hypoadrenocorticism had a urine sodium concentration less than 30 mmol/L. Urine sodium concentration in dogs with hypoadrenocorticism was significantly higher (median 103 mmol/L, range: 41 to 225) than in dogs with non-adrenal illness (median 10 mmol/L, range: 2 to 86) (P<0·0005). Serum sodium concentrations were not significantly different between dogs with hypoadrenocorticism and dogs with non-adrenal illness. CLINICAL SIGNIFICANCE: These results suggest that urine sodium concentrations can be used to prioritise a differential diagnosis of hypoadrenocorticism in hyponatraemic dogs. A urine sodium concentration less than 30 mmol/L in a hyponatraemic dog makes classical hypoadrenocorticism an unlikely cause of the hyponatraemia. Nevertheless, because of the small sample size our results should be interpreted with caution and a larger follow-up study would be valuable.

Influence of ration composition on nutritive and digestive variables in captive giraffes (Giraffa camelopardalis) indicating the appropriateness of feeding practice.

The nutrition of captive giraffe (Giraffa camelopardalis), a browsing ruminant, is challenging because browse availability is limited in zoos and rations need to be composed of compensatory feeds. In this study, ration composition for giraffes in 12 German zoos was documented and linked to animal variables that indicate suitability of nutrition. Rations differed in proportion of ration items and chemical composition resulting in various grades of accordance with feeding recommendations. An estimated daily metabolisable energy (ME) intake (MEI; mean ± SD) of 0.61 MJ ME/kg0.75 body weight (BW; ±0.1) was sufficient to cover estimated energy requirements. Daily dry matter (DM) intake (DMI) was 61 g DM/kg0.75 BW (±10) and correlated negatively to dietary ME content (p = .009; r = -.596). Apparently, feed intake was regulated by energetic satiety and not by physical properties of forage. A negative correlation between produce proportion and DMI (p = .002; r = -.676) led to the assumption of a low ruminal pH in giraffes fed high proportions of produce. Increasing dietary forage proportions led to an increasing duration of feed intake (p = .045; r = .477) and decreasing occurrence of oral stereotypies (p = .047; r = -.474). The weighted average faecal particle size was larger than reported for free-ranging giraffes, but no relation to ration characteristics among the facilities existed. The abrasiveness of rations was not excessive, as contents of silicate in faeces were similar to values from the wild. Body condition was generally acceptable, but there was no evident relation to ration characteristics. The capacity to self-regulate DM and ME intakes with lucerne hay may work at higher forage proportions than often assumed for captive giraffes. Rations with less energetic density can result in a greater DMI, including maximisation of forage intake and reduction of oral stereotypies.

Comparative selective retention of particle size classes in the gastrointestinal tract of ponies and goats.

There is a discrepancy in the literature on potential digesta separation mechanisms in horses, with both a selective retention of fine and of large particles postulated in different publications. To assess the net effect of such mechanisms, we fed ponies on a hay-only diet a pulse dose of whole (unchopped) marked hay together with a solute marker, collected faeces on a regular basis, measured marker concentrations in whole faeces and in their large (2.0-16 mm), medium (0.5-1.0 mm) and small (0.063-0.25 mm) particle fraction, and calculated the corresponding mean retention times (MRTs). For comparison, the same experiment was performed in goats. In goats, as expected, MRTsolute (35 hr) was significantly shorter than MRTparticle (51 hr); only a very small fraction of particle marker was excreted as large particles (2%); and the MRT of these large particles was significantly shorter than that of small particles (with a relevant difference of 8.6 hr), indicating that those few large particles that escape the rumen do so mostly soon after ingestion. In ponies, MRTsolute (24 hr) did not differ from MRTparticle (24 hr); a higher fraction of particle marker was excreted as large particles (5%); and the MRT of these large particles was longer than that of small particles (but with a non-relevant difference of less than 1 hr). These results indicate that no relevant net separation of digesta phases occurs in horses and that selective particle retention mechanisms in the large intestine are unlikely to represent important characteristics of the horse's digestive physiology.

Differential effects of monensin and a blend of essential oils on rumen microbiota composition of transition dairy cows.

In response to oral application, monensin alters the rumen microbiota, increasing ruminal propionate production and energy availability in the animal. Data from different studies indicate that the susceptibility of rumen bacteria to monensin is mainly cell-wall dependent but tracing its activity to specific microbial groups has been challenging. Several studies have shown a similar effect for essential oils but results are inconsistent. To investigate the influence of monensin and a blend of essential oils (BEO, containing thymol, guaiacol, eugenol, vanillin, salicylaldehyde, and limonene) on the rumen microbiome, rumen liquid samples were collected orally on d 56 postpartum from cows that had either received a monensin controlled-release capsule 3 wk antepartum, a diet containing a BEO from 3 wk antepartum onward, or a control diet (n = 12). The samples were analyzed for pH, volatile fatty acid, ammonia, and lipopolysaccharide concentrations and protozoal counts. A 16S rRNA gene fingerprinting analysis (PCR-single-strand conformation polymorphism) and sequencing revealed that the BEO treatment had no effect on the rumen microbiota, whereas monensin decreased bacterial diversity. Twenty-three bacterial species-level operational taxonomic units were identified for which monensin caused a significant decrease in their relative abundance, all belonging to the phyla Bacteroidetes (uncultured BS11 gut group and BS9 gut group) and Firmicutes (Lachnospiraceae, Ruminococcaceae, and Erysipelotrichaceae). Ten bacterial operational taxonomic units belonging to the phyla Actinobacteria (Coriobacteriaceae), Bacteroidetes (Prevotella), Cyanobacteria (SHA-109), and Firmicutes (Lachnospiraceae and Ruminococcaceae) increased in relative abundance due to the monensin treatment. These results confirm the hypothesis that varying effects depending on cell-wall constitution and thickness might apply for monensin sensitivity rather than a clear-cut difference between gram-negative and gram-positive bacteria. No effect of monensin on the archaea population was observed, confirming the assumption that reported inhibition of methanogenesis is most likely caused through a decrease in substrate availability, rather than by a direct effect on the methanogens. The data support the hypothesis that the observed increase in ruminal molar propionate proportions due to monensin may be caused by a decrease in abundance of non-producers and moderate producers of propionate and an increase in abundance of succinate and propionate producers.

Dry matter and digesta particle size gradients along the goat digestive tract on grass and browse diets.

Physical properties of the digesta vary along the ruminant digestive tract. They also vary within the forestomach, leading to varying degrees of rumen contents stratification in 'moose-type' (browsing) and 'cattle-type' (intermediate and grazing) ruminants. We investigated the dry matter concentration (DM) and the mean digesta particle size (MPS) within the forestomach and along the digestive tract in 10 goats fed grass hay or dried browse after a standardized 12-h fast, euthanasia and freezing in the natural position. In all animals, irrespective of diet, DM showed a peak in the omasum and an increase from caecum via colon towards the faeces and a decrease in MPS between the reticulum and the omasum. Both patterns are typical for ruminants in general. In the forestomach, there was little systematic difference between more cranial and more caudal locations ('horizontal stratification'), with the possible exception of large particle segregation in the dorsal rumen blindsac on the grass diet. In contrast, the typical (vertical) contents stratification was evident for DM (with drier contents dorsally) and, to a lower degree, for MPS (with larger particles dorsally). Although evident in both groups, this stratification was more pronounced on the grass diet. The results support the interpretation that differences in rumen contents stratification between ruminants are mainly an effect of species-specific physiology, but can be enhanced due to the diet consumed.

Oral Health in Primary Care: A Framework for Action.

KNOWLEDGE TRANSFER STATEMENT:: This special communication presents the Oral Health Delivery Framework, a conceptual model for incorporating preventive oral health care in routine medical care and improving referrals from primary care to dentistry. The framework, along with supporting case examples and stakeholder actions, was published in Oral Health: An Essential Component of Primary Care in June 2015. To access the full white paper and supporting resources, visit www.QualisHealth.org/white-paper .

On the dose sensitivity of a new CDMAM phantom.

For the technical quality assurance of breast cancer screening protocols several phantoms have been developed. Their dose sensitivity is a common topic often discussed in literature. The European protocol for the quality control of the physical and technical aspects of mammography screening suggests a contrast-detail phantom like the CDMAM phantom (Artinis Medical Systems, Elst, NL). The CDMAM 3.4 was tested with respect to its dose sensitivity and compared to other phantoms in a recent paper. The CDMAM 4.0 phantom provides other disc diameters and thicknesses adapted more closely to the image quality found in modern mammography systems. This motivates a comparison of the two generations using the same exposure parameters. We varied the time-current (mAs) within a range of clinically used values (40-140 mAs). All evaluations were done using automatic evaluation software provided by Artinis (for CDMAM 4.0) and the National Coordinating Centre for the Physics of Mammography, Guildford UK (CDMAM 3.4). We compared the relative dose sensitivity with respect to the different diameters and also computed the IQFinv parameter, which averages over the diameters as suggested in the manual for the phantom. The IQFinv parameter linearly depends on dose for both phantoms. The CDMAM 4.0 shows a more monotonous dependence on dose, the total variation of the threshold thicknesses as functions of the dose are significantly smaller than with the CDMAM 3.4. As the automatic evaluation shows rather different threshold thicknesses for the two phantoms, conversion factors for human to automatic readout have to be adapted.

A review and classification of approaches for dealing with uncertainty in multi-criteria decision analysis for healthcare decisions.

Multi-criteria decision analysis (MCDA) is increasingly used to support decisions in healthcare involving multiple and conflicting criteria. Although uncertainty is usually carefully addressed in health economic evaluations, whether and how the different sources of uncertainty are dealt with and with what methods in MCDA is less known. The objective of this study is to review how uncertainty can be explicitly taken into account in MCDA and to discuss which approach may be appropriate for healthcare decision makers. A literature review was conducted in the Scopus and PubMed databases. Two reviewers independently categorized studies according to research areas, the type of MCDA used, and the approach used to quantify uncertainty. Selected full text articles were read for methodological details. The search strategy identified 569 studies. The five approaches most identified were fuzzy set theory (45% of studies), probabilistic sensitivity analysis (15%), deterministic sensitivity analysis (31%), Bayesian framework (6%), and grey theory (3%). A large number of papers considered the analytic hierarchy process in combination with fuzzy set theory (31%). Only 3% of studies were published in healthcare-related journals. In conclusion, our review identified five different approaches to take uncertainty into account in MCDA. The deterministic approach is most likely sufficient for most healthcare policy decisions because of its low complexity and straightforward implementation. However, more complex approaches may be needed when multiple sources of uncertainty must be considered simultaneously.

Tooth length and incisal wear and growth in guinea pigs (Cavia porcellus) fed diets of different abrasiveness.

Dental diseases are among the most important reasons for presenting guinea pigs (Cavia porcellus) and other rodents to veterinary clinics, but the aetiopathology of this disease complex is unclear. Clinicians tend to believe that the ever-growing teeth of rabbits and rodents have a constant growth that needs to be worn down by the mastication of an appropriate diet. In this study, we tested the effect of four different pelleted diets of increasing abrasiveness [due to both internal (phytoliths) and external abrasives (sand)] or whole grass hay fed for 2 weeks each in random order to 16 guinea pigs on incisor growth and wear, and tooth length of incisors and cheek teeth. There was a positive correlation between wear and growth of incisors. Tooth lengths depended both on internal and external abrasives, but only upper incisors were additionally affected by the feeding of whole hay. Diet effects were most prominent in anterior cheek teeth, in particular M1 and m1. Cheek tooth angle did not become shallower with decreasing diet abrasiveness, suggesting that a lack of dietary abrasiveness does not cause the typical 'bridge formation' of anterior cheek teeth frequently observed in guinea pigs. The findings suggest that other factors than diet abrasiveness, such as mineral imbalances and in particular hereditary malocclusion, are more likely causes for dental problems observed in this species.

A navigation system for flexible endoscopes using abdominal 3D ultrasound.

A navigation system for flexible endoscopes equipped with ultrasound (US) scan heads is presented. In contrast to similar systems, abdominal 3D-US is used for image fusion of the pre-interventional computed tomography (CT) to the endoscopic US. A 3D-US scan, tracked with an optical tracking system (OTS), is taken pre-operatively together with the CT scan. The CT is calibrated using the OTS, providing the transformation from CT to 3D-US. Immediately before intervention a 3D-US tracked with an electromagnetic tracking system (EMTS) is acquired and registered intra-modal to the preoperative 3D-US. The endoscopic US is calibrated using the EMTS and registered to the pre-operative CT by an intra-modal 3D-US/3D-US registration. Phantom studies showed a registration error for the US to CT registration of 5.1 mm±2.8 mm. 3D-US/3D-US registration of patient data gave an error of 4.1 mm compared to 2.8 mm with the phantom. From this we estimate an error on patient experiments of 5.6 mm.

Group decision making with the analytic hierarchy process in benefit-risk assessment: a tutorial.

The analytic hierarchy process (AHP) has been increasingly applied as a technique for multi-criteria decision analysis in healthcare. The AHP can aid decision makers in selecting the most valuable technology for patients, while taking into account multiple, and even conflicting, decision criteria. This tutorial illustrates the procedural steps of the AHP in supporting group decision making about new healthcare technology, including (1) identifying the decision goal, decision criteria, and alternative healthcare technologies to compare, (2) structuring the decision criteria, (3) judging the value of the alternative technologies on each decision criterion, (4) judging the importance of the decision criteria, (5) calculating group judgments, (6) analyzing the inconsistency in judgments, (7) calculating the overall value of the technologies, and (8) conducting sensitivity analyses. The AHP is illustrated via a hypothetical example, adapted from an empirical AHP analysis on the benefits and risks of tissue regeneration to repair small cartilage lesions in the knee.