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Chronische Lymphabflussstörungen sind in der Human- wie auch der Veterinärmedizin bekannte Krankheitsbilder. Deutlich seltener ist ein akuter Lymphstau, der bei Haustieren kaum einmal beschrieben wurde. Umso relevanter erscheint der nachfolgende Fallbericht eines akuten sekundären hochgradigen Lymphstaus bei einem Hund.

Pathological lesions of feet occur frequently in captive elephant populations. To improve foot health, it is important to identify risk factors associated with such pathologies. Several previous studies have analyzed potentially influencing factors but were limited, for example, by small sample sizes. This study analyzed the relationship between 87 independent variables and the foot health score of 204 Asian elephants (Elephas maximus) in European zoos using bivariate correlation, multivariable regression models, and principal component analysis (PCA). Correlation and regression tests revealed significant results for 30 different variables, mainly with small effect sizes. Only three variables were significant in more than one test: sex, time spent indoors, and time spent on hard ground, with lower scores (i.e. less or less severe pathological lesions) in females, and when less time is spent indoors or on hard ground. Due to small effect sizes and differing results of the statistical tests, it is difficult to determine which risk factors are most important. Instead, a holistic consideration appears more appropriate. A biplot of the PCA shows that factors representing more advanced husbandry conditions (e.g. large areas, high proportions of sand flooring) were associated with each other and with decreased foot scores, whereas indicators of more limited conditions (e.g. high proportions of hard ground, much time spent indoors) were also associated with each other but increased the foot score. In conclusion, instead of resulting from just one or two factors, reduced foot health might be an indicator of a generally poorer husbandry system.

Despite increased research during the past years, many characteristics of resting behavior in elephants are still unknown. For example, there is only limited data suggesting elephants express longer lying bouts and increased total nightly lying durations on soft substrates as compared to hard surfaces. Additionally, it has not been investigated how frequently elephants change body sides between lying bouts. Here we present these characteristics based on observations of nighttime lying behavior in 10 zoo elephants (5 African Loxodonta africana and 5 Asian Elephas maximus elephants) living in five different European facilities. We found that elephants housed on soft substrates have significantly increased total lying durations per night and longer average lying bouts. Furthermore, at 70%-85% of all bouts, a consistently higher frequency of side change between lying bouts occurred on soft substrates, leading to an overall equal laterality in resting behavior. Deviations from this pattern became evident in elephants living on nonsand flooring or/and in nondominant individuals of nonfamily groups, respectively. Based on our findings, we consider elephants to normally have several lying bouts per night with frequent side changes, given an appropriate substrate and healthy social environment. We encourage elephant-keeping facilities to monitor these characteristics in their elephants' nighttime behavior to determine opportunities for further improvements and detect alterations putatively indicating social or health problems in individual elephants at an early stage.

A new and uniquely structured matrix of mammalian phenotypes,MaTrics(MammalianTraits for Comparative Genomics) in a digital form is presented. By focussing on mammalian species for which genome assemblies are available,MaTricsprovides an interface between mammalogy and comparative genomics.MaTricswas developed within a project aimed to find genetic causes of phenotypic traits of mammals usingForward Genomics.This approach requires genomes and comprehensive and recorded information on homologous phenotypes that are coded as discrete categories in a matrix.MaTricsis an evolving online resource providing information on phenotypic traits in numeric code; traits are coded either as absent/present or with several states as multistate. The state record for each species is linked to at least one reference (e.g., literature, photographs, histological sections, CT scans, or museum specimens) and soMaTricscontributes to digitalization of museum collections. Currently,MaTricscovers 147 mammalian species and includes 231 characters related to structure, morphology, physiology, ecology, and ethology and available in a machine actionable NEXUS-format*. FillingMaTricsrevealed substantial knowledge gaps, highlighting the need for phenotyping efforts. Studies based on selected data fromMaTricsand usingForward Genomicsidentified associations between genes and certain phenotypes ranging from lifestyles (e.g., aquatic) to dietary specializations (e.g., herbivory, carnivory). These findings motivate the expansion of phenotyping inMaTricsby filling research gaps and by adding taxa and traits. Only databases likeMaTricswill provide machine actionable information on phenotypic traits, an important limitation to genomics.MaTricsis available within the data repository Morph·D·Base (www.morphdbase.de).

For ruminants and arboreal herbivores (sloths and colobine monkeys), an influence of digestive physiology on resting postures has been postulated that is linked to the interplay of digestive anatomy and the gravity vector. To further explore this putative relationship, we observed 253 individual terrestrial mammalian herbivores at zoological gardens, noting 29,478 resting events in 36 species during the day and 7,383 resting events of 18 species at night, providing a catalogue of mammalian resting postures. We confirm the constraint of ruminants to sternal recumbency and expand this observation to camelids, which rely on a similar sorting mechanism in their forestomach for rumination, but which use lateral recumbency to a slight but distinctively larger proportion. Generally, larger herbivores rest more in a standing position, and use lateral recumbency more when lying. The use of lateral recumbency in large hindgut fermenters (perissodactyls, elephants) and nonruminant foregut fermenters (macropods, hippos) corresponds to the concept that there is no interplay between gravity and digestive physiology in these species. By contrast, peccaries, hyraxes, and hystricomorph rodents never used lateral recumbency. While this may be related to body size, body shape, or other species-specific characteristics, it also suggests that the interplay of gravity and digestive processes, in particular with the colonic separation mechanism in hystricomorph rodents, should be further investigated.

The inactivation of ancestral protein-coding genes (gene loss) can be associated with phenotypic modifications. Within placental mammals, repeated losses of PNLIPRP1 (gene inhibiting fat digestion) occurred preferentially in strictly herbivorous species, whereas repeated NR1I3 losses (gene involved in detoxification) occurred preferentially in strictly carnivorous species. It was hypothesized that lower fat contents of herbivorous diets and lower toxin contents of carnivorous diets cause relaxed selection pressure on these genes, resulting in the accumulation of mutations and ultimately to convergent gene losses. However, because herbivorous and carnivorous diets differ vastly in their composition, a fine-grained analysis is required for hypothesis testing. We generated a trait matrix recording diet and semi-quantitative estimates of fat and toxin consumption for 52 placental species. By including data from 31 fossil taxa, we reconstructed the ancestral diets in major lineages (grundplan reconstruction). We found support that PNLIPRP1 loss is primarily associated with low levels of fat intake and not simply with herbivory/carnivory. In particular, PNLIPRP1 loss also occurred in carnivorous lineages feeding on a fat-poor diet, suggesting that the loss of this gene may be beneficial for occupying ecological niches characterized by fat-poor food resources. Similarly, we demonstrated that carnivorous species are indeed less exposed to diet-related toxins, suggesting that the loss of NR1I3 and related genes (NR1I2 and UGT1A6) resulted from relaxed selection pressure. This study illustrates the need of detailed phenotype studies to obtain a deeper understanding of factors underlying gene losses and to progress in understanding genomic causes of phenotypic variation in mammals.

An often-stated ecomorphological assumption that has the status of ‘textbook knowledge’ is that the dimensions of the digestive tract correlate with diet, where herbivores—consuming diets of lower digestibility—have longer intestinal tracts than faunivores—consuming diets of higher digestibility. However, statistical approaches have so far failed to demonstrate this link. Here, we collated data on the length of intestinal sections and body mass of 519 mammal species, and test for various relationships with trophic, climatic and other biological characteristics. All models showed a strong phylogenetic signal. Scaling relationships with body mass showed positive allometry at exponents greater than 0.33, except for the caecum, which is particularly large in smaller species. Body mass was more tightly linked to small intestine than to large intestine length. Adding a diet proxy to the relationships increased model fit for all intestinal sections, except for the small intestine when accounting for phylogeny. Thus, the diet has a main effect on the components of the large intestine, with longer measures in herbivores. Additionally, measures of habitat aridity had a positive relationship with large intestine length. The small intestine was longer in species from colder habitats at higher latitudes, possibly facilitating the processing of peak intake rates during the growing season. This study corroborates intuitive expectations on digestive tract anatomy, while the dependence of significant results on large sample sizes and inclusion of specific taxonomic groups indicates that the relationships cannot be considered fixed biological laws.

In current clinical practice, care of diseased patients is often restricted to separated disciplines. However, such an organ‐centered approach is not always suitable. For example, cognitive dysfunction is a severe burden in heart failure patients. Moreover, these patients have an increased risk for age‐associated dementias. The underlying molecular mechanisms are presently unknown, and thus, corresponding therapeutic strategies to improve cognition in heart failure patients are missing. Using mice as model organisms, we show that heart failure leads to specific changes in hippocampal gene expression, a brain region intimately linked to cognition. These changes reflect increased cellular stress pathways which eventually lead to loss of neuronal euchromatin and reduced expression of a hippocampal gene cluster essential for cognition. Consequently, mice suffering from heart failure exhibit impaired memory function. These pathological changes are ameliorated via the administration of a drug that promotes neuronal euchromatin formation. Our study provides first insight to the molecular processes by which heart failure contributes to neuronal dysfunction and point to novel therapeutic avenues to treat cognitive defects in heart failure patients., Patients suffering from heart failure have an increased risk to develop age‐associated dementia. This study elucidates the underlying mechanisms and provides evidence that heart‐failure induced cognitive decline is linked to epigenetic changes that affect neuronal gene expression.

Several established models in human and veterinary medicine exist to evaluate an individual health or disease status. Many of these seem unsuitable for further epidemiological research aimed at discovering underlying influential factors. As a case example for score development and choice, the present study analyses different approaches to scoring the foot health of Asian elephants (Elephas maximus) living in European facilities. Sum scores with varying degree of detail, and without or with a weighting method, were compared using descriptive statistics, ie kurtosis, skewness, Shannon entropy, total redundancy, their maximum and their actual ranges. With increasing score complexity, a higher level of differentiation was reached. In parallel, the distribution of score frequencies in the population shifted systematically: with the least complex scoring model the pattern indicated a severely unhealthy population with an opposite skew to a hypothetically healthy population, whereas the most complex scoring model indicated a mildly affected population with a skew corresponding to that expected for a healthy population. We propose the latter, in the form of the Particularised Severity Score (ParSev), which accounts for every nail and pad individually and weights the sub-scores by squaring, as the most relevant score for further investigations, either in assessing changes within an elephant population over time, or correlating foot health in epidemiological studies to potentially influencing factors. Our results emphasise the relevance of choosing appropriate scoring models for welfare-associated evaluations, due to implications for the applicability as well as the perceived welfare status of the test population.

In current clinical practice care of diseased patients is often restricted to separated disciplines. However, such an organ-centered approach is not always suitable. For example, cognitive dysfunction is a severe burden in heart failure patients. Moreover, these patients have an increased risk for age-associated dementias. The underlying molecular mechanisms are presently unknown and thus corresponding therapeutic strategies to improve cognition in heart failure patients are missing. Using mice as model organisms we show that heart failure leads to specific changes in hippocampal gene-expression, a brain region intimately linked to cognition. These changes reflect increased cellular stress pathways which eventually lead to loss of neuronal euchromatin and reduced expression of a hippocampal gene cluster essential for cognition. Consequently, mice suffering from heart failure exhibit impaired memory function. These pathological changes are ameliorated via the administration of a drug that promotes neuronal euchromatin formation. Our study provides first insight to the molecular processes by which heart failure contributes to neuronal dysfunction and point to novel therapeutic avenues to treat cognitive defects in heart failure patients.

1. Animals in seasonal environments often rely on photoperiodicity to time their reproduction. Elephants have a gestation length of approximately two years and a historical geographic distribution including higher latitudes than at present, so the evolution of a seasonal breeding pattern cued by photoperiodicity and timed to the long-day period is a theoretical option in both species. 2. We reviewed literature on reproductive patterns in free-ranging, semi-captive and captive Asian and African elephants, photoperiodic cueing, seasonal variation of body condition and other factors influencing their reproduction, as well as data from zoological collections on the timing of births. 3. Most of the free-ranging and all the semi-captive and captive elephant populations showed a moderate yet distinct seasonal breeding pattern. 4. Peak breeding activity of free-ranging Asian elephants took place in either the dry or the wet season, with no preference for short-day or long-day breeding at low latitudes (close to the equator) but a preference for long-day breeding at higher latitudes. Semi-captive Asian elephants mainly bred in the dry season when body condition was lowest and day-lengths were increasing. Peak conception often occurred in the wet season in free-ranging African elephants when body condition was highest, with no evident preference for short-day or long-day breeding at low latitudes but preference for long-day breeding at higher latitudes. 5. Asian and African elephants in zoos at latitudes from 43 to 53°N tended to conceive more often during spring and summer, i.e. when day-lengths were increasing. Body condition was not reported to vary significantly throughout the year and was rather high compared to in the wild. 6. We hypothesise that elephants are ‘long-day breeders’ in which the photoperiodic timing of conception can be influenced by many additional factors. Strategies to encourage natural conception in captive populations should include measures aimed at increasing breeding incentives in the northern hemisphere spring.

Elephants do not replace deciduous teeth once with permanent teeth as most mammals, but replace a single cheek tooth per jaw-side five times in their lives in a process called molar progression. While this gradual process has been well-documented for the purpose of age determination, a less-considered possible side effect of this progression is that functional chewing surface fluctuates, being larger when two cheek teeth are both partially in use and smaller when only one cheek tooth is used fully. We found that body mass of both breeding and non-breeding female zoo elephants (Elephas maximus, Loxodonta africana) shows a cyclic undulation with peaks separated by many years, which is therefore unrelated to reproduction or annual seasonality. We propose variation in functional chewing surface, resulting chew¬ing efficiency, and resulting increased food intake and/or digestive efficiency as the underlying cause. As elephants reproduce all year-round and thus are not synchronized in their molar progression pattern, climate-related fluctuations in resource availability are likely to mask this pattern in free-ranginganimals. In contrast, it emerges under the comparatively constant zoo conditions, and illustrates the relevance of the dental apparatus for herbivorous mammals. The combination of variable chewing efficiency and resource availability in free-ranging elephants may render these species particularly prone to reported inter-individual fitness differences.

Caring for all aspects of zoo elephants' well-being is considered a major challenge. Providing an appropriate flooring substrate to facilitate lying rest presents a meaningful part of a holistic management concept. Investigating the impact of a new sand flooring on the nocturnal resting behavior of a breeding group of seven African elephants living at one zoo revealed more total lying rest, longer bouts of lying rest and a reduced side preference in the adult females. With an average total daily lying rest of about 1.5-2.0 hrs, the investigated zoo elephants expressed longer lying rest compared to recently reported data from free-ranging individuals in Botswana. In addition, the presence of nursing calves in the observed elephant group seemed to impact the resting pattern of all group members, with around 60% of all lying bouts being discontinued after interruption by the youngsters. With respect to observed nursing during leaning rest, we encourage the installation of appropriate horizontal structures in breeding facilities to support leaning rest behavior of their female elephants. In doing so, zoos may improve rest quality of nursing females, and, in general, the welfare aspect of sleep for their elephants.

Regular body mass (BM) monitoring plays a key role in preventative health care of zoo animals. In some species, including African (Loxodonta africana) and Asian elephants (Elephas maximus), the process of weighing can be challenging, and alternative methods such as visual body condition scoring (BCS) have been developed. We investigated the temporal development of both parameters regarding correlation patterns between them, and their suitability as monitoring measures in dependence of an elephant’s life stage. While BM is more suitable in calves and juveniles under the age of 8 years, both BM and BCS are considered equally reliable in adult elephants. In elephants over the age of 40 years, BCS might be more suitable for assessing the physical status. Independent of species and sex, juvenile zoo elephants grow in BM nearly linearly with age, and reach a higher BM at an earlier age compared with conspecifics of free‐ranging and semi‐captive populations in the countries of origin. The BCS typically remains constant during this life stage, seemingly unaffected by growth. In adult animals, breeding females have a lower BM and BCS than nonbreeders, and BM and BCS typically indicate fluctuations in the same direction. In geriatric elephants (>40 years) a drop in BCS occurs commonly, while BM may even increase in this life stage. We recommend regular body mass recording in zoo elephants to enhance our knowledge of body mass development and allow the formulation of objective practical recommendations. BCS presents a valuable and simple tool for complementary monitoring of an elephant’s condition, especially in adult and geriatric individuals.

Little attention has been paid to the resting and sleeping behavior of zoo elephants so far. An important concern is when elephants avoid lying down, due to degenerative joint and foot disease, social structure, or stressful environmental changes. Inability or unwillingness to lie down for resting is an important welfare issue, as it may impair sleep. We emphasize the importance of satisfying rest in elephants by reviewing the literature on resting behavior in elephants (Loxodonta africana and Elephas maximus) as well as the documentation of four cases from European zoos and our own direct observations in a zoo group of four female African elephants during 12 entire days. The common denominator in the case reports is the occurrence of a falling bout out of a standing position subsequently to a cessation of lying rest for different periods of time. Although well-known in horses as "episodic collapse" or "excessive drowsiness," this syndrome has not been described in elephants before. To enable its detection, we recommend nocturnal video monitoring for elephant-keeping institutions. The literature evaluation as well as own observational data suggest an inverse relationship between lying rest and standing rest. Preventative measures consist of enclosure modifications that facilitate lying rest (e.g., sand hills) or standing rest in a leaning position as a substitute. Anecdotal observations suggest that the provision of appropriate horizontal environmental structures may encourage safe, sleep-conducive standing rest. We provide drawings on how to install such structures. Effects of providing such structures should be evaluated in the future.