933 resultados para Horse stable
Resumo:
In April 2008 a Franches-Montagnes colt was born with an unusual coat colour phenotype which had never been observed in that population before. The foal showed extended white markings on body and legs, a white head and blue eyes. As both parents have an unremarkable bay coat colour phenotype, a de novo mutation was expected in the offspring and a candidate gene approach revealed a spontaneous mutation in the microphthalmia associated transcription factor gene (MITF). A detailed clinical examination in 2010 indicated an impaired hearing capacity. As in the American Paint Horse large white facial markings in combination with blue eyes are associated with deafness, the hearing capacity of the stallion was closer examined performing brainstem auditory-evoked responses (BAER). The BAER confirmed bilateral deafness in the Franches-Montagnes colt. It is assumed that the deafness is caused by a melanocyte deficiency caused by the MITF gene mutation. Unfortunately, due to castration of the horse, the causal association between the mutation in the MITF gene and clinical findings cannot be confirmed by experimental matings.
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Horses were domesticated from the Eurasian steppes 5,000-6,000 years ago. Since then, the use of horses for transportation, warfare, and agriculture, as well as selection for desired traits and fitness, has resulted in diverse populations distributed across the world, many of which have become or are in the process of becoming formally organized into closed, breeding populations (breeds). This report describes the use of a genome-wide set of autosomal SNPs and 814 horses from 36 breeds to provide the first detailed description of equine breed diversity. F(ST) calculations, parsimony, and distance analysis demonstrated relationships among the breeds that largely reflect geographic origins and known breed histories. Low levels of population divergence were observed between breeds that are relatively early on in the process of breed development, and between those with high levels of within-breed diversity, whether due to large population size, ongoing outcrossing, or large within-breed phenotypic diversity. Populations with low within-breed diversity included those which have experienced population bottlenecks, have been under intense selective pressure, or are closed populations with long breed histories. These results provide new insights into the relationships among and the diversity within breeds of horses. In addition these results will facilitate future genome-wide association studies and investigations into genomic targets of selection.
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Intense selective pressures applied over short evolutionary time have resulted in homogeneity within, but substantial variation among, horse breeds. Utilizing this population structure, 744 individuals from 33 breeds, and a 54,000 SNP genotyping array, breed-specific targets of selection were identified using an F(ST)-based statistic calculated in 500-kb windows across the genome. A 5.5-Mb region of ECA18, in which the myostatin (MSTN) gene was centered, contained the highest signature of selection in both the Paint and Quarter Horse. Gene sequencing and histological analysis of gluteal muscle biopsies showed a promoter variant and intronic SNP of MSTN were each significantly associated with higher Type 2B and lower Type 1 muscle fiber proportions in the Quarter Horse, demonstrating a functional consequence of selection at this locus. Signatures of selection on ECA23 in all gaited breeds in the sample led to the identification of a shared, 186-kb haplotype including two doublesex related mab transcription factor genes (DMRT2 and 3). The recent identification of a DMRT3 mutation within this haplotype, which appears necessary for the ability to perform alternative gaits, provides further evidence for selection at this locus. Finally, putative loci for the determination of size were identified in the draft breeds and the Miniature horse on ECA11, as well as when signatures of selection surrounding candidate genes at other loci were examined. This work provides further evidence of the importance of MSTN in racing breeds, provides strong evidence for selection upon gait and size, and illustrates the potential for population-based techniques to find genomic regions driving important phenotypes in the modern horse.
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Equine insect bite hypersensitivity (IBH) is a seasonal IgE-mediated dermatosis caused by bites of insects of the genus Culicoides. A familial predisposition for the disease has been shown but, except for the MHC, the genes involved have not been identified so far. An immunogenomic analysis of IBH was performed in a model population of Old Kladruby horses, all living in the same environment. Clinical signs of IBH were used as phenotypic manifestation of IBH. Furthermore, total serum IgE levels were determined in the sera of these horses and used as an independent phenotypic marker for the immunogenetic analysis. Single nucleotide polymorphisms (SNPs) in candidate immunity-related genes were used for association analyses. Genotypes composed of two to five genes encoding interferon gamma -IFNG, transforming growth factor beta 1 -TGFB1, Janus kinase 2 -JAK2, thymic stromal lymphopoietin -TSLP, and involucrin -IVL were associated with IBH, indicating a role of the genes in the pathogenesis of IBH. These findings were supported by analysis of gene expression in skin biopsies of 15 affected and 15 unaffected horses. Two markers associated with IBH, IFNG and TGFB1, showed differences in mRNA expression in skin biopsies from IBH-affected and non-affected horses (p<0.05). Expression of the gene coding for the CD14 receptor molecule -CD14 was different in skin biopsies at p<0.06. When total IgE levels were treated as binary traits, genotypes of IGHE, ELA-DRA, and IL10/b were associated with this trait. When treated as a continuous trait, total IgE levels were associated with genes IGHE, FCER1A, IL4, IL4R, IL10, IL1RA, and JAK2. This first report on non-MHC genes associated with IBH in horses is thus supported by differences in expression of genes known to play a role in allergy and immunity.
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CASE DESCRIPTION A 7-year-old 573-kg (1,261 -lb) Swiss Warmblood gelding was evaluated because of signs of acute abdominal pain. CLINICAL FINDINGS Physical examination revealed a markedly distended abdomen with subjectively reduced borborygmi in all abdominal quadrants. A large, gas-distended viscus was present at the pelvic brim preventing complete palpation of the abdomen per rectum. Ultrasonographic evaluation could not be safely performed in the initial evaluation because of severe signs of abdominal pain. TREATMENT AND OUTCOME Ventral midline celiotomy was performed, and right dorsal displacement of the ascending colon was corrected. Progressive signs of abdominal pain after surgery prompted repeat ventral midline celiotomy, and small intestinal incarceration in a large, radial mesojejunal rent was detected. The incarceration was reduced, but the defect was not fully accessible for repair via the celiotomy. Repair of the mesenteric defect was not attempted, and conservative management was planned after surgery; however, signs of colic returned. A standard laparoscopic approach was attempted from both flanks in the standing patient, but the small intestine could not be adequately mobilized for full evaluation of the rent. Hand-assisted laparoscopic surgery (HALS) allowed identification and reduction of jejunal incarceration and repair of the mesenteric rent. Although minor ventral midline incisional complications were encountered, the horse recovered fully. CLINICAL RELEVANCE HALS techniques should be considered for repair of mesenteric rents in horses. In the horse of this report, HALS facilitated identification, evaluation, and repair of a large radial mesenteric rent that was not accessible from a ventral median celiotomy.
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A case of pulmonary tuberculosis caused by Mycobacterium tuberculosis was diagnosed in a horse. Clinical evaluation performed prior to euthanasia did not suggest tuberculosis, but postmortem examination provided pathological and bacteriological evidence of mycobacteriosis. In the lungs, multiple tuberculoid granulomas communicating with the bronchiolar lumen, pleural effusion, and a granulomatous lymphadenitis involving mediastinal and tracheobronchial lymph nodes were found. Serologic response to M. tuberculosis antigens was detected in the infected horse, but not in the group of 42 potentially exposed animals (18 horses, 14 alpacas, 6 donkeys, and 4 dogs) which showed no signs of disease. Diagnosis of tuberculosis in live horses remains extremely difficult. Four of 20 animal handlers at the farm were positive for tuberculous infection upon follow-up testing by interferon-gamma release assay, indicating a possibility of interspecies transmission of M. tuberculosis.
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Abstract. Here we present stable isotope data from three sediment records from lakes that lie along the Macedonian- Albanian border (Lake Prespa: 1 core, and Lake Ohrid: 2 cores). The records only overlap for the last 40 kyr, although the longest record contains the MIS 5/6 transition (Lake Ohrid). The sedimentary characteristics of both lakes differ significantly between the glacial and interglacial phases. At the end of MIS 6 Lake Ohrid’s water level was low (high �18Ocalcite) and, although productivity was increasing (high calcite content), the carbon supply was mainly from inorganic catchment rock sources (high �13Ccarb). During the last interglacial, calcite and TOC production and preservation increased, progressively lower �18Ocalcite suggest increase in humidity and lake levels until around 115 ka. During ca. 80 ka to 11 ka the lake records suggest cold conditions as indicated by negligible calcite precipitation and low organic matter content. In Lake Ohrid, �13Corg are complacent; in contrast, Lake Prespa shows consistently higher �13Corg suggesting a low oxidation of 13C-depleted organic matter in agreement with a general deterioration of climate conditions during the glacial. From 15 ka to the onset of the Holocene, calcite and TOC begin to increase, suggesting lake levels were probably low (high �18Ocalcite). In the Holocene (11 ka to present) enhanced productivity is manifested by high calcite and organic matter content. All three cores show an early Holocene characterised by low �18Ocalcite, apart from the very early Holocene phase in Prespa where the lowest �18Ocalcite occurs at ca. 7.5 ka, suggesting a phase of higher lake level only in (the more sensitive) Lake Prespa. From 6 ka, �18Ocalcite suggest progressive aridification, in agreement with many other records in the Mediterranean, although the uppermost sediments in one core records low �18Ocalcite which we interpret as a result of human activity. Overall, the isotope data present here confirm that these two big lakes have captured the large scale, low frequency palaeoclimate variation that is seen in Mediterranean lakes, although in detail there is much palaeoclimate information that could be gained, especially small scale, high frequency differences between this region and the Mediterranean.
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The single-celled protozoan Trypanosoma brucei spp. is the causative agent of human African trypanosomiasis and nagana in cattle. Quantitative proteomics for the first time allowed for the characterization of the proteome from several different life stages of the parasite (1-3). To achieve this, stable isotope labeling by amino acids in cell culture (SILAC; (4)) was adapted to T. brucei spp. cultures. T. brucei cells grown in standard media with dialyzed fetal calf serum containing heavy isotope-labeled amino acids (arginine and lysine) show efficient incorporation of the labeled amino acids into the whole cell proteome (8-12 divisions) and no detectable amino acid conversions. The method can be applied to both of the major life stages of the parasite and in combination with RNAi or gene knock-out approaches.
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Every year around 100 million male piglets are castrated in the EU, usually without anaesthesia or post-operative analgesia. This surgical intervention is painful and stressful. Several main players within the pig industry have voluntarily agreed to end the practice of surgical pig castration in the EU by 2018. One alternative to castration is entire male pig production. However, entire males behave differently than castrates, for example, by performing more mounting behaviour, which is suggested to be a welfare problem. The aim of our study was to develop a comprehensive ethogram of different types of mounting and to investigate properties, causes and consequences of mounting behaviour in finishing pigs. The study included 80 entire male and 80 female pigs from two farrowing batches born six weeks apart. Mixed sex and single-sex housing of pigs are both common in pig farming, so to ensure our study was representative, the 160 pigs were assigned to social groups of 20 in three treatments: entire male pigs only (MM, 2 groups, n = 40), entire females only (FF, 2 groups, n = 40) and entire males and females mixed together (MF, 4 groups, n = 80). Measurements took place during the final six weeks before slaughter (between 63.5 and 105.5 kg). Observations of mounting behaviour on 12 days per batch suggested that: (i) males mounted more than females, (ii) within sex, there was no effect of treatment on the amount of mounting (although the statistical power of the study to detect these effects was low), and (iii) there were individual differences in mounting that were stable over time (within sex). Classification of mounting into different categories revealed that sexual mounting was most common overall and in males but only rare in females. Compared to other types of mounting (e.g. caused by crowding or during a fight), sexual mounts lasted longer and provoked more screaming by the recipient. There were no relationships between mounting behaviour on the one hand and dominance rank in food competition tests, the circulating levels of sex hormones (oestradiol, testosterone and progesterone) at the end of the study, the health scores (lameness and scratches) or weight gain on the other hand. The stable individual differences of mounting over time suggest that mounting behaviour is a trait of the individual rather than the appearance of random outbreaks. However, these differences in mounting cannot be explained by dominance behaviour or by differences in sex hormone concentrations that could indicate the onset of puberty. Mounting behaviour and in particular sexual mounting provoked high pitched screaming of the recipients indicating that mounting is a welfare problem. For the welfare assessment of entire male pig production the performance of mounting behaviour should be considered. (C) 2013 Elsevier B.V. All rights reserved.
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Temporohyoid osteoarthropathy (THO) is a well-recognised clinical entity in horses. Temporohyoid osteoarthropathy is characterised by progressive osseous proliferation of the proximal portion of the stylohyoid and petrous temporal bones, and is generally described as a disease of middle-aged horses. More recent reports also attribute a variety of clinical syndromes in young horses to THO, requiring a diversification of approaches to confirm the diagnosis and its significance, and to guide conservative and surgical treatment options. This commentary will review the purported aetiology, clinical syndromes, available diagnostic tests and treatment options of equine THO.
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Testosterone (TES) 6-β-hydroxylation is a significant metabolic step in the biotransformation of TES in human liver microsomes and reflects cytochrome P450 (CYP) 3A4/5 specific metabolic activity. Several CYP3A enzymes have been annotated in the horse genome, but functional characterization is missing. This descriptive study investigates TES metabolism in the horse liver in vitro and the qualitative contribution of three CYP3A isoforms of the horse. Metabolism of TES was investigated by using equine hepatocyte primary cultures and liver microsomes. Chemical inhibitors were used to determine the CYPs involved in TES biotransformation in equine microsomes. Single CYPs 3A89, 3A94, and 3A95, recombinantly expressed in V79 hamster lung fibroblasts, were incubated with TES and the fluorescent metabolite 7-benzyloxy-4-trifluoromethylcoumarin (BFC). The effect of ketoconazole and troleandomycin was evaluated on single CYPs. Testosterone metabolites were analyzed by HPLC and confirmed by GC/MS. In hepatocyte primary cultures, the most abundant metabolite was androstenedione (AS), whereas in liver microsomes, 6-β-hydroxytestosterone showed the largest peak. Formation of 6-β-hydroxytestosterone and 11-β-hydroxytestosterone in liver microsomes was inhibited by ketoconazole, troleandomycin, and quercetin. Equine recombinant CYP3A95 catalyzed 11-β-hydroxylation of testosterone (TES). Metabolism of BFC was significantly inhibited by ketoconazole in CYP3A95, whereas troleandomycin affected the activities of CYP3A94 and CYP3A95. Both inhibitors had no significant effect on CYP3A89. Metabolic reactions and effects of inhibitors differed between the equine CYP3A isoforms investigated. This has to be considered in future in vitro studies.
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Purpose Stereotypes about leadership still represent a potent barrier to women’s advancement to leadership roles. Successful leaders are perceived to possess predominately agentic traits (e.g., assertive, dominant) that are more similar to those ascribed to men than women. This perceived incongruity of people’s beliefs about leaders and women underlies prejudice against women leaders (Eagly & Karau, 2002). Thus, an important question is whether such stereotypical beliefs about the traits of leaders, men, and women incorporate change or stability over time. Design/Methodology To examine this question, 235 Irish business students (113 men, 122 women) rated a target group’s characteristics (men, women, middle managers) as of a specific time (50 years ago, present, 50 years into the future) on gender‐stereotypical traits. Results Following Schein’s (1973) approach, intraclass correlation coefficients estimated the extent to which the stereotype of managers was similar to that of men or women. The results showed a large, significant correlation between the stereotypes about men and managers within each time condition and overall. In contrast, the women‐manager correlation was negative and nonsignificant overall. However, this negative correlation weakened from the past to the present and became positive and marginally significant for the future. Research/Practical Implications Altogether the results suggest that people perceive stereotypes about leaders to be more similar to men than to women. These perceptions may continue to function as impediments to women leaders’ advancement despite the trend over time toward femalemanager similarity. Originality/Value To our knowledge this is the first study to systematically test perceptions of change in the think manager‐think male stereotype overtime.
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Pío XI, the largest glacier of the Southern Patagonia Icefield, reached its neoglacial maximum extent in 1994 and is one of the few glaciers in that area which is not retreating. In view of the recent warming it is important to understand glacier responses to climate changes. Due to its remoteness and the harsh conditions in Patagonia, no systematic mass balance studies have been performed. In this study we derived net accumulation rates for the period 2000–2006 from a 50 m (33.2 4 m weq) ice core collected in the accumulation area of Pío XI (2600 m a.s.l., 49°16'40"S, 73°21'14"W). Borehole temperatures indicate near temperate ice, but the average melt percent is only 16 ± 14%. Records of stable isotopes are well preserved and were used for identification of annual layers. Net accumulation rates range from 3.4–7.1 water equivalent (m weq) with an average of 5.8 m weq, comparable to precipitation amounts at the Chilean coast, but not as high as expected for the Icefield. Ice core stable isotope data correlate well with upper air temperatures and may be used as temperature proxy.