A Non-Synonymous HMGA2 Variant Decreases Height in Shetland Ponies and Other Small Horses

The identification of quantitative trait loci (QTL) such as height and their underlying causative variants is still challenging and often requires large sample sizes. In humans hundreds of loci with small effects control the heritable portion of height variability. In domestic animals, typically only a few loci with comparatively large effects explain a major fraction of the heritability. We investigated height at withers in Shetland ponies and mapped a QTL to ECA 6 by genome-wide association (GWAS) using a small cohort of only 48 animals and the Illumina equine SNP70 BeadChip. Fine-mapping revealed a shared haplotype block of 793 kb in small Shetland ponies. The HMGA2 gene, known to be associated with height in horses and many other species, was located in the associated haplotype. After closing a gap in the equine reference genome we identified a non-synonymous variant in the first exon of HMGA2 in small Shetland ponies. The variant was predicted to affect the functionally important first AT-hook DNA binding domain of the HMGA2 protein (c.83G>A; p.G28E). We assessed the functional impact and found impaired DNA binding of a peptide with the mutant sequence in an electrophoretic mobility shift assay. This suggests that the HMGA2 variant also affects DNA binding in vivo and thus leads to reduced growth and a smaller stature in Shetland ponies. The identified HMGA2 variant also segregates in several other pony breeds but was not found in regular-sized horse breeds. We therefore conclude that we identified a quantitative trait nucleotide for height in horses.

Assessment of Intramedullary Spinal Pressure in Small Breed Dogs With Thoracolumbar Disk Extrusion Undergoing Hemilaminectomy

OBJECTIVE To assess intramedullary spinal pressure (IMP) in small breed dogs with thoracolumbar disk extrusion. STUDY DESIGN Prospective cohort study. ANIMALS Small breed dogs (n = 14) with thoracolumbar disk extrusion undergoing hemilaminectomy and healthy chondrodystrophic laboratory dogs (control; n = 3) without spinal disease. METHODS Diagnosis was based on clinical and neurological examinations and magnetic resonance imaging (MRI) and was confirmed intraoperatively. A standardized anesthesia protocol and surgical procedure were used to minimize factors that could influence IMP. Intramedullary pressure was measured through a minidurotomy at the site of spinal cord compression using a fiber optic catheter inserted perpendicular to the longitudinal axis of the spinal cord. Measurements were taken after hemilaminectomy and again after removal of extruded disk material. RESULTS Affected dogs had significantly higher IMP compared to control dogs (P = .008) and IMP decreased significantly post-decompression compared with initial values (P < .001). No correlation was found between IMP and neurologic grade, degree of spinal cord compression on MRI, or signal intensity changes on MRI. CONCLUSION Acute thoracolumbar disk extrusion is associated with increased IMP in small breed dogs and surgical decompression results in an immediate decrease of IMP.

Coxiella burnetii Infections in Small Ruminants and Humans in Switzerland

The recent Q fever epidemic in the Netherlands raised concerns about the potential risk of outbreaks in other European countries. In Switzerland, the prevalence of Q fever in animals and humans has not been studied in recent years. In this study, we describe the current situation with respect to Coxiella (C.) burnetii infections in small ruminants and humans in Switzerland, as a basis for future epidemiological investigations and public health risk assessments. Specific objectives of this cross-sectional study were to (i) estimate the seroprevalence of C. burnetii in sheep and goats, (ii) quantify the amount of bacteria shed during abortion and (iii) analyse temporal trends in human C. burnetii infections. The seroprevalence of C. burnetii in small ruminants was determined by commercial ELISA from a representative sample of 100 sheep flocks and 72 goat herds. Herd-level seroprevalence was 5.0% (95% CI: 1.6-11.3) for sheep and 11.1% (95% CI: 4.9-20.7) for goats. Animal-level seroprevalence was 1.8% (95% CI: 0.8-3.4) for sheep and 3.4% (95% CI: 1.7-6) for goats. The quantification of C. burnetii in 97 ovine and caprine abortion samples by real-time PCR indicated shedding of >10(4) bacteria/g in 13.4% of all samples tested. To our knowledge, this is the first study reporting C. burnetii quantities in a large number of small ruminant abortion samples. Annual human Q fever serology data were provided by five major Swiss laboratories. Overall, seroprevalence in humans ranged between 1.7% and 3.5% from 2007 to 2011, and no temporal trends were observed. Interestingly, the two laboratories with significantly higher seroprevalences are located in the regions with the largest goat populations as well as, for one laboratory, with the highest livestock density in Switzerland. However, a direct link between animal and human infection data could not be established in this study.

Magnetic Resonance Imaging Finding in Small Ruminants with Brain

Brain disease is an important cause of neurologic deficits in small ruminants, however few MRI features have been described. The aim of this retrospective, case series study was to describe MRI characteristics in a group of small ruminants with confirmed brain disease. A total of nine small ruminants (six sheep and three goats) met inclusion criteria. All had neurologic disorders localized to the brain and histopathologic confirmation. In animals with toxic-metabolic diseases, there were bilaterally symmetric MRI lesions affecting either the gray matter (one animal with polioencephalomalacia) or the white matter (two animals with enterotoxemia). In animals with suppurative inflammation, asymmetric focal brainstem lesions were present (two animals with listeric encephalitis), or lesions typical of an intra-axial (one animal) or dural abscess (one animal), respectively. No MRI lesions were detected in one animal with suspected viral cerebellitis and one animal with parasitic migration tracts. No neoplastic or vascular lesions were identified in this case series. Findings from the current study supported the use of MRI for diagnosing brain diseases in small ruminants.

Hit-and-run trophallaxis of small hive beetles

Some parasites of social insects are able to exploit the exchange of food between nestmates via trophallaxis, because they are chemically disguised as nestmates. However, a few parasites succeed in trophallactic solicitation although they are attacked by workers. The underlying mechanisms are not well understood. The small hive beetle (=SHB), Aethina tumida, is such a parasite of honey bee, Apis mellifera, colonies and is able to induce trophallaxis. Here, we investigate whether SHB trophallactic solicitation is innate and affected by sex and experience. We quantified characteristics of the trophallactic solicitation in SHBs from laboratory-reared individuals that were either bee-naïve or had 5 days experience. The data clearly show that SHB trophallactic solicitation is innate and further suggest that it can be influenced by both experience and sex. Inexperienced SHB males begged more often than any of the other groups had longer breaks than their experienced counterparts and a longer soliciting duration than both experienced SHB males and females, suggesting that they start rather slowly and gain more from experience. Successful experienced females and males were not significantly different from each other in relation to successful trophallactic interactions, but had a significantly shorter soliciting duration compared to all other groups, except successful inexperienced females. Trophallactic solicitation success, feeding duration and begging duration were not significantly affected by either SHB sex or experience, supporting the notion that these behaviors are important for survival in host colonies. Overall, success seems to be governed by quality rather than quantity of interactions, thereby probably limiting both SHB energy investment and chance of injury (<1%). Trophallactic solicitation by SHBs is a singular example for an alternative strategy to exploit insect societies without requiring chemical disguise. Hit-and-run trophallaxis is an attractive test system to get an insight into trophallaxis in the social insects.

Msh2 status modulates both apoptosis and mutation frequency in the murine small intestine

Deficiency in genes involved in DNA mismatch repair increases susceptibility to cancer, particularly of the colorectal epithelium. Using Msh2 null mice, we demonstrate that this genetic defect renders normal intestinal epithelial cells susceptible to mutation in vivo at the Dlb-1 locus. Compared with wild-type mice, Msh2-deficient animals had higher basal levels of mutation and were more sensitive to the mutagenic effects of temozolomide. Experiments using Msh2-deficient cells in vitro suggest that an element of this effect is attributable to increased clonogenicity. Indeed, we show that Msh2 plays a role in the in vivo initiation of apoptosis after treatment with temozolomide, N-methyl-N′-nitro-N-nitrosoguanidine, and cisplatin. This was not influenced by the in vivo depletion of O6-alkylguanine-DNA-alkyltransferase after administration of O6-benzylguanine . By analyzing mice mutant for both Msh2 and p53, we found that the Msh2-dependent apoptotic response was primarily mediated through a p53-dependent pathway. Msh2 also was required to signal delayed p53-independent death. Taken together, these studies characterize an in vivo Msh2-dependent apoptotic response to methylating agents and raise the possibility that Msh2 deficiency may predispose to malignancy not only through failed repair of mismatch DNA lesions but also through the failure to engage apoptosis.

Coiled Bodies Preferentially Associate with U4, U11, and U12 Small Nuclear RNA Genes in Interphase HeLa Cells but Not with U6 and U7 Genes

Coiled bodies (CBs) are nuclear organelles involved in the metabolism of small nuclear RNAs (snRNAs) and histone messages. Their structural morphology and molecular composition have been conserved from plants to animals. CBs preferentially and specifically associate with genes that encode U1, U2, and U3 snRNAs as well as the cell cycle–regulated histone loci. A common link among these previously identified CB-associated genes is that they are either clustered or tandemly repeated in the human genome. In an effort to identify additional loci that associate with CBs, we have isolated and mapped the chromosomal locations of genomic clones corresponding to bona fide U4, U6, U7, U11, and U12 snRNA loci. Unlike the clustered U1 and U2 genes, each of these loci encode a single gene, with the exception of the U4 clone, which contains two genes. We next examined the association of these snRNA genes with CBs and found that they colocalized less frequently than their multicopy counterparts. To differentiate a lower level of preferential association from random colocalization, we developed a theoretical model of random colocalization, which yielded expected values for χ2 tests against the experimental data. Certain single-copy snRNA genes (U4, U11, and U12) but not controls were found to significantly (p < 0.000001) associate with CBs. Recent evidence indicates that the interactions between CBs and genes are mediated by nascent transcripts. Taken together, these new results suggest that CB association may be substantially augmented by the increased transcriptional capacity of clustered genes. Possible functional roles for the observed interactions of CBs with snRNA genes are discussed.

Transposable elements as sources of variation in animals and plants

A tremendous wealth of data is accumulating on the variety and distribution of transposable elements (TEs) in natural populations. There is little doubt that TEs provide new genetic variation on a scale, and with a degree of sophistication, previously unimagined. There are many examples of mutations and other types of genetic variation associated with the activity of mobile elements. Mutant phenotypes range from subtle changes in tissue specificity to dramatic alterations in the development and organization of tissues and organs. Such changes can occur because of insertions in coding regions, but the more sophisticated TE-mediated changes are more often the result of insertions into 5′ flanking regions and introns. Here, TE-induced variation is viewed from three evolutionary perspectives that are not mutually exclusive. First, variation resulting from the intrinsic parasitic nature of TE activity is examined. Second, we describe possible coadaptations between elements and their hosts that appear to have evolved because of selection to reduce the deleterious effects of new insertions on host fitness. Finally, some possible cases are explored in which the capacity of TEs to generate variation has been exploited by their hosts. The number of well documented cases in which element sequences appear to confer useful traits on the host, although small, is growing rapidly.

Genetic engineering of carbohydrate biosynthetic pathways in transgenic mice demonstrates cell cycle-associated regulation of glycoconjugate production in small intestinal epithelial cells.

Proliferation, migration-associated differentiation, and cell death occur continuously and in a spatially well-organized fashion along the crypt-villus axis of the mouse small intestine, making it an attractive system for studying how these processes are regulated and interrelated. A pathway for producing glycoconjugates was engineered in adult FVB/N transgenic mice by expressing a human alpha 1,3/4-fucosyltransferase (alpha 1,3/4-FT; EC 2.4.1.65) along the length of this crypt-villus axis. The alpha 1,3/4-FT can use lacto-N-tetraose or lacto-neo-N-tetraose core chains to generate Lewis (Le) blood group antigens Le(a) or Le(x), respectively, and H type 1 or H type 2 core chains to produce Leb and Le(y). Single- and multilabel immunohistochemical studies revealed that expression of the alpha 1,3/4-FT results in production of Le(a) and Leb antigens in both undifferentiated proliferated crypt cells and in differentiated postmitotic villus-associated epithelial cells. In contrast, Le(x) antigens were restricted to crypt cells. Villus enterocytes can be induced to reenter the cell cycle by expression of simian virus 40 tumor antigen under the control of a promoter that only functions in differentiated members of this lineage. Bitransgenic animals, generated from a cross of FVB/N alpha 1,3/4-FT with FVB/N simian virus 40 tumor antigen mice, expand the range of Le(x) expression to include villus-associated enterocytes that have reentered the cell cycle. Thus, the fucosylations unveil a proliferation-dependent switch in oligosaccharide production, as defined by a monoclonal antibody specific for the Le(x) epitope. These findings show that genetic engineering of oligosaccharide biosynthetic pathways can be used to define markers for entry into, or progression through, the cell cycle and to identify changes in endogenous carbohydrate metabolism that occur when proliferative status is altered in a manner that is not deleterious to the system under study.

Quo vadis Aethina tumida? Biology and control of small hive beetles

Small hive beetles (SHBs) are generalists native to sub-Saharan Africa and reproduce in association with honeybees, bumblebees, stingless bees, fruits and meat. The SHB has recently become an invasive species, and introductions have been recorded from America, Australia, Europe and Asia since 1996. hile SHBs are usually considered a minor pest in Africa, they can cause significant damage to social bee colonies in their new ranges. Potential reasons for differential impact include differences in bee behaviour, climate and release from natural enemies. Here, we provide an overview on biology, distribution, pest status, diagnosis, control and prevention to foster adequate mitigation and stimulate future research. SHBs have become a global threat to both apiculture and wild bee populations, but our knowledge of this pest is still limited, reating demand for more research in all areas of its biology.

Novel antennal lobe substructures revealed in the small hive beetle Aethina tumida

The small hive beetle, Aethina tumida, is an emerging pest of social bee colonies. A. tumida shows a specialized life style for which olfaction seems to play a crucial role. To better understand the olfactory system of the beetle, we used immunohistochemistry and 3-D reconstruction to analyze brain structures, especially the paired antennal lobes (AL), which represent the first integration centers for odor information in the insect brain. The basic neuroarchitecture of the A. tumida brain compares well to the typical beetle and insect brain. In comparison to other insects, the AL are relatively large in relationship to other brain areas, suggesting that olfaction is of major importance for the beetle. The AL of both sexes contain about 70 olfactory glomeruli with no obvious size differences of the glomeruli between sexes. Similar to all other insects including beetles, immunostaining with an antiserum against serotonin revealed a large cell that projects from one AL to the contralateral AL to densely innervate all glomeruli. Immunostaining with an antiserum against tachykinin-related peptides (TKRP) revealed hitherto unknown structures in the AL. Small TKRP-immunoreactive spherical substructures are in both sexes evenly distributed within all glomeruli. The source for these immunoreactive islets is very likely a group of about 80 local AL interneurons. We offer two hypotheses on the function of such structures.

Optimized methods for extracting circulating small RNAs from long-term stored equine samples.

Circulating miRNAs in body fluids, particularly serum, are promising candidates for future routine biomarker profiling in various pathologic conditions in human and veterinary medicine. However, reliable standardized methods for miRNA extraction from equine serum and fresh or archived whole blood are sorely lacking. We systematically compared various miRNA extraction methods from serum and whole blood after short and long-term storage without addition of RNA stabilizing additives prior to freezing. Time of storage at room temperature prior to freezing did not affect miRNA quality in serum. Furthermore, we showed that miRNA of NGS-sufficient quality can be recovered from blood samples after >10 years of storage at -80 °C. This allows retrospective analyses of miRNAs from archived samples.

The domestic encyclopaedia; or, A dictionary of facts, and useful knowledge : comprehending a concise view of the latest discoveries, inventions, and improvements, chiefly applicable to rural and domestic economy. Together with descriptions of the most interesting objects of nature and art; the history of men and animals, in a state of health or disease; and practical hints respecting the arts and manufactures, both familiar and commercial, illustrated with numerous engravings and cuts in five volumes /

S & S,

VM/SAC, veterinary medicine/small animal clinician.

Mode of access: Internet.