Abnormal bone mineralization in a puppy fed an imbalanced raw meat homemade diet diagnosed and monitored using dual-energy X-ray absorptiometry

A 4-month-old male Old English Sheepdog was presented for evaluation of a raw meat-based homemade diet after a 1-month history of progressive lameness. Marked dietary deficiencies were detected, which included calcium, phosphorus and vitamin D. Hypovitaminosis D and hypocalcaemia were diagnosed by serum analysis. Evidence of severe diffuse osteopenia was noted on survey radiographs. Dual-energy X-ray absorptiometry (DEXA) was used to quantify bone mineral content and density and compare to published reference ranges. The puppy's initial bone mineralization was markedly subnormal, with bone mineral density 66% lower than expected, and bone mineral content 40% lower than expected. Subsequent DEXA scans were performed at intervals during the puppy's recovery to document the rate of bone re-mineralization and guide therapeutic recommendations. Marked improvement was achieved within 4 months through exercise control and feeding of a diet appropriately formulated for large breed puppy growth and development. This report reinforces the necessity of thorough dietary history and highlights the potential for malnutrition in pets fed homemade and raw meat-based diets. Use of DEXA has rarely been reported in clinical cases, yet can be a valuable tool for diagnosing and monitoring cases with abnormal bone mineralization. Further studies using DEXA to track bone mineralization in healthy puppies are encouraged to develop a more robust reference range of bone mineralization in growing dogs of varying sizes, weights and ages.     

Landscape-level naturalness of conservation easements in a mixed-use matrix

Context

With underrepresentation of habitats in publicly protected areas, attention has focused on the function of alternative land conservation mechanisms. Private conservation easements (CEs) have proliferated in the United States, yet assessing landscape-level function is confounded by varying extent, resolution, and temporal scale.

Objectives

We developed and tested an assessment tool to evaluate interacting spatial, social, and environmental attributes of easements relative to the degree of human modification (HM). We hypothesized that on both private and public conservation properties HM would be lower than on non-conserved parcels, and that for fine-scale features (most CEs), the level of HM would be driven by the variables used to create the coarser scale HM measure.

Methods

Variation in HM between private, public, and non-conserved was tested via pairwise parcel sampling. Composition was evaluated using multiple geographic bounds and edge characteristics. We assessed both environmental and social predictors using multinomial logistic regression.

Results

Privately conserved lands did not differ significantly from non-conserved lands. Publicly conserved lands had lower HM than both privately conserved and non-conserved lands. Edge contrast was similar between private and matched non-conserved patches. The level of HM was not driven by distance to roads, or by elevation in this mixed-use setting.

Conclusions

Variation in tests for differences, land characteristics, and HM variables confirmed the significantly lower HM of publicly protected lands, and opens the question as to naturalness of easements in some contexts. CEs in this location may be representative of the mixed rural-forested landscape instead of more natural land cover.

     

Protective effect of butylated hydroxylanisole against hydrogen peroxide-induced apoptosis in primary cultured mouse hepatocytes

Butylated hydroxyanisole (BHA) is a synthetic phenolic compound consisting of a mixture of two isomeric organic compounds: 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. We examined the effect of BHA against hydrogen peroxide (H₂O₂)-induced apoptosis in primary cultured mouse hepatocytes. Cell viability was significantly decreased by H₂O₂ in a dose-dependent manner. Additionally, H₂O₂ treatment increased Bax, decreased Bcl-2, and promoted PARP-1 cleavage in a dose-dependent manner. Pretreatment with BHA before exposure to H₂O₂ significantly attenuated the H₂O₂-induced decrease of cell viability. H₂O₂ exposure resulted in an increase of intracellular reactive oxygen species (ROS) generation that was significantly inhibited by pretreatment with BHA or N-acetyl-cysteine (NAC, an ROS scavenger). H₂O₂-induced decrease of cell viability was also attenuated by pretreatment with BHA and NAC. Furthermore, H₂O₂-induced increase of Bax, decrease of Bcl-2, and PARP-1 cleavage was also inhibited by BHA. Taken together, results of this investigation demonstrated that BHA protects primary cultured mouse hepatocytes against H₂O₂-induced apoptosis by inhibiting ROS generation.     

Effect of Season on Travel Patterns and Hoof Growth of Domestic Horses

Four Morgan mares and five Morgan geldings ranging in age from 5- to 12-years-old were fitted with Global Positioning System units to determine if season has an influence on travel pattern. Body and hoof growth measurements were obtained so that the influence of season on body condition and hoof growth could be determined. Waist and heart circumference, cresty neck score, and body condition score were determined in each season. The ambient temperature and precipitation was recorded for each season. Waist circumference was the greatest (P < .05) in the spring and summer and the least in the fall and winter. Hoof growth was the greatest (P < .05) in the fall and the least in the winter. The front and rear hooves grew at similar rates in all horses. Hoof growth in geldings and mares were also similar. The average distances traveled were similar across seasons; however, the horse did numerically travel more in the spring and summer compared with the fall and winter. The range of the travel pattern was influenced by season with the horses traveling significantly less in the winter, although the average travel distances were similar. In conclusion, season in temperate zones will influence body condition, hoof growth, and pattern of travel, but the total distance traveled will be similar. Further research needs to be conducted to determine the influence of season on hoof growth and travel patterns.     

A single IGF1 allele is a major determinant of small size in dogs

The domestic dog exhibits greater diversity in body size than any other terrestrial vertebrate. We used a strategy that exploits the breed structure of dogs to investigate the genetic basis of size. First, through a genome-wide scan, we identified a major quantitative trait locus (QTL) on chromosome 15 influencing size variation within a single breed. Second, we examined genetic variation in the 15-megabase interval surrounding the QTL in small and giant breeds and found marked evidence for a selective sweep spanning a single gene (IGF1), encoding insulin-like growth factor 1. A single IGF1 single-nucleotide polymorphism haplotype is common to all small breeds and nearly absent from giant breeds, suggesting that the same causal sequence variant is a major contributor to body size in all small dogs.     

In vivo investigation of changes in biomarkers of oxidative stress induced by plant food rich diets

It is well established that vegetables and fruit (VF) contain antioxidant phytochemicals. Consequently, it is expected that individuals who consume diets with a high content of VF should be better protected against oxidative cellular damage than individuals who do not, but not all data support this assumption. The objective of this study was to identify possible explanations for this conundrum. The effects of two diets that differed in VF content on markers of oxidative damage were studied. Sixty-four women participated in a 14-day dietary intervention. Subjects consumed on average either 3.6 or 12.1 servings of VF per day. The primary end points assessed were 8-hydroxy-2-deoxyguanosine (8-oxo-dG) in peripheral lymphocyte DNA and 8-isoprostaglandin F-2alpha (8-iso-PGF2alpha) excreted in urine. Subjects consuming the high versus low VF diet had lower concentrations of 8-oxo-dG (p < 0.01) and of 8-iso-PGF2alpha (p < 0.01). However, the reduction in oxidative end points by high VF was not uniform. Rather, an antioxidant effect was observed primarily in individuals whose oxidative end points at baseline were above the median for the study population. Using change in plasma carotenoids (end point minus baseline measurements) as an index of phytochemical intake, the reduction in oxidative markers was inversely proportional to change in plasma carotenoids; this effect was stronger for lipid peroxidation (p < 0.01) than DNA oxidation (p < 0.05). These findings imply that increasing exogenous antioxidant exposure may primarily benefit individuals with elevated levels of oxidative stress. Null findings do not necessarily indicate that an antioxidant compound lacks in vivo activity.     

Cokriging particle size fractions of the soil

It is often necessary to predict the distribution of mineral particles in soil between size fractions, given observations at sample sites. Because the contents in each fraction necessarily sum to 100%, these values constitute a composition, which we may assume is drawn from a random compositional variate. Elements of a D‐component composition are subject to non‐stochastic constraints; they are constrained to lie on a D– 1 dimensional simplex. This means we cannot treat them as realizations of unbounded random variables such as the multivariate Gaussian. For this reason, there are theoretical reasons not to use ordinary cokriging (or ordinary kriging) to map particle size distributions. Despite this, the compositional constraints on data on particle size fractions are not always accounted for by soil scientists. The additive log‐ratio (alr) transform can be used to transform data from a compositional variate into a form that can be treated as a realization of an unbounded random variable. Until now, while soil scientists have made use of the alr transform for the spatial prediction of particle size, there has been concern that the simple back‐transform of the optimal estimate of the alr‐transformed variables does not yield the optimal estimate of the composition. A numerical approximation to the conditional expectation of the composition has been proposed, but we are not aware of examples of its application and it has not been used in soil science. In this paper, we report two case studies in which we predicted clay, silt and sand contents of the soil at test sites by ordinary cokriging of the alr‐transformed data followed by both the direct (biased) back‐transform of the estimates and the unbiased back‐transform. We also computed estimates by ordinary cokriging of the untransformed data (which ignores the compositional constraints on the variables) for comparison. In one of our case studies, the benefit of using the alr transform was apparent, although there was no consistent advantage in using the unbiased back‐transform. In the other case study, there was no consistent advantage in using the alr transform, although the bias of the simple back‐transform was apparent. The differences between these case studies could be explained with respect to the distribution on the simplex of the particle size fractions at the two sites.     

The behaviour of soil process models of ammonia volatilization at contrasting spatial scales

Process models are commonly used in soil science to obtain predictions at a spatial scale that is different from the scale at which the model was developed, or the scale at which information on model inputs is available. When this happens, the model and its inputs require aggregation or disaggregation to the application scale, and this is a complex problem. Furthermore, the validity of the aggregated model predictions depends on whether the model describes the key processes that determine the process outcome at the target scale. Different models may therefore be required at different spatial scales. In this paper we develop a diagnostic framework which allows us to judge whether a model is appropriate for use at one or more spatial scales both with respect to the prediction of variations at those scale and in the requirement for disaggregation of the inputs. We show that spatially nested analysis of the covariance of predictions with measured process outcomes is an efficient way to do this. This is applied to models of the processes that lead to ammonia volatilization from soil after the application of urea. We identify the component correlations at different scales of a nested scheme as the diagnostic with which to evaluate model behaviour. These correlations show how well the model emulates components of spatial variation of the target process at the scales of the sampling scheme. Aggregate correlations were identified as the most pertinent to evaluate models for prediction at particular scales since they measure how well aggregated predictions at some scale correlate with aggregated values of the measured outcome. There are two circumstances under which models are used to make predictions. In the first case only the model is used to predict, and the most useful diagnostic is the concordance aggregate correlation. In the second case model predictions are assimilated with observations which should correct bias in the prediction, and errors in the variance; the aggregate correlations would be the most suitable diagnostic.