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Copyright of ESPOCH Congresses: The Ecuadorian Journal of S.T.E.A.M. is the property of Knowledge E DMCC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This case report addresses the problem of underreporting negative results and adverse side effects in animal testing. We present our findings regarding a hyperphagic mouse model associated with unforeseen high mortality. The results outline the necessity of reporting detailed information in the literature to avoid duplication.Obese mouse models are essential in the study of obesity, metabolic syndrome and diabetes mellitus. An experimental model of obesity can be induced by the administration of gold thioglucose (GTG). After transcending the blood-brain barrier, the GTG molecule interacts with regions of the ventromedial hypothalamus, thereby primarily targeting glucose-sensitive neurons. When these neurons are impaired, mice become insensitive to the satiety effects of glucose and develop hyperphagia. In a pilot study for optimising dosage and body weight development, C57BL/6 mice were treated with GTG (0.5 mg/g body weight) or saline, respectively. Animals were provided a physiological amount of standard diet (5 g per animal) for the first 24 hours after treatment to prevent gastric dilatation. Within 24 hours after GTG injection, all GTG-treated animals died of gastric overload and subsequent circulatory shock. Animals developed severe attacks of hyperphagia, and as the amount of provided chow was restricted, mice exhibited unforeseen pica and ingested bedding material. These observations strongly suggest that restricted feeding is contraindicated concerning GTG application. Presumably, the impulse of excessive food intake was a strong driving force. Therefore, the actual degree of suffering in the GTG-induced model of hyperphagia should be revised from moderate to severe. [ABSTRACT FROM AUTHOR]

The barrier effect is a pervasive impact of road networks. For many small mammals individual avoidance responses can be the mechanism behind the barrier effect. However, little attention has been paid to which species and road characteristics modulate road avoidance and mortality risk. We measured the strength of the barrier effect imposed by the road on three rodent species with different body sizes and habitat specializations: Southern water vole ( Arvicola sapidus ), Mediterranean pine vole ( Microtus duodecimcostatus ) and Algerian mouse ( Mus spretus ). We analysed the effect of traffic intensity on use of space and direction of movement and the effect of road type (4-lane highway, 2-lane paved road and 1-lane unpaved road) on crossing rates with simulations of roads bisecting each home range. Finally, we estimated annual mortality risk from collision based on individual speed, crossing rates, body length, traffic volume and road width. Individual mobility and ecological preferences were assumed as two hypotheses to explain species’ responses towards roads. The effects were species-specific, with traffic intensity having a negative influence on the use of space and movement directionality only for water voles and with avoidance of paved roads being evident for the Algerian mouse. Road-kill mortality risk was high in pine voles. Habitat specialization, individual mobility and home-range location were identified as important factors of species’ responses towards roads. This study draws attention to the role of behaviour and ecological requirements as well as road characteristics on the strength of the barrier effect imposed by roads for different species. [ABSTRACT FROM AUTHOR]

Different control methods (i.e. Zinc Phosphide 2% and 3%; Super Caid 0.005% and Live traps) against Rattus norvegicus Berk., evaluated by food consumption method in poultry farm (Bortos village -El Warraq area) at Giza Governorate during August and September 2016. The highest poison baits daily consumption were recorded when used Super Caid 0.005% (52.53 and 40.39 g/night) followed by Zinc phosphide 2% (0.23 and 1.93 g/night) and Zinc phosphide 3% (0.09 and 0.26 g/night) ) inside and outside building. The Super Caid 0.005% treatment gave high mortality numbers against R. norvegicus inside and outside the building. The pest mortality records increased from 3rd day until 6th day of treatment. Mortality records during treatment (inside building) were 7, 6, 6, 4 and 2 individuals in 7, 6, 5, 3 and 4 days, respectively. While mortality records during treatment (outside building) were 11 and 8 individuals in 6 and 7 days, respectively. The highest reduction of R. norvegicus when used Super Caid 0.005% were 79.98 and 46.04 % followed by Zinc phosphide 2% (51.85 and 36.51 %) and Zinc phosphide 3% (67.6 and 32.15 %) ) inside and outside building. While, when used live trap bait items inside building with attractants such as: tomato, lanshon, cucumber and falfel the reduction percentages in rat individuals were 78.41, 61.32, 92.43 and -65.1%, respectively. The analysis of variance and treatment means were significantly different between plain bait daily consumption pre-treatment of all transactions (Super Caid 0.005%, Zinc phosphide 2% and 3% inside and outside building and also live trap bait items). [ABSTRACT FROM AUTHOR]

Background: Strongyloides stercoralis, the chief causative agent of human strongyloidiasis, is a nematode globally distributed but mainly endemic in tropical and subtropical regions. Chronic infection is often clinically asymptomatic but it can result in severe hyperinfection syndrome or disseminated strongyloidiasis in immunocompromised patients. There is a great diversity of techniques used in diagnosing the disease, but definitive diagnosis is accomplished by parasitological examination of stool samples for morphological identification of parasite. Until now, no molecular method has been tested in urine samples as an alternative to stool samples for diagnosing strongyloidiasis. This study aimed to evaluate the use of a new molecular LAMP assay in a well-established Wistar rat experimental infection model using both stool and, for the first time, urine samples. The LAMP assay was also clinically evaluated in patients´ stool samples. Methodology/Principal Findings: Stool and urine samples were obtained daily during a 28-day period from rats infected subcutaneously with different infective third-stage larvae doses of S. venezuelensis. The dynamics of parasite infection was determined by daily counting the number of eggs per gram of feces from day 1 to 28 post-infection. A set of primers for LAMP assay based on a DNA partial sequence in the 18S rRNA gene from S. venezuelensis was designed. The set up LAMP assay (namely, Strong-LAMP) allowed the sensitive detection of S. venezuelensis DNA in both stool and urine samples obtained from each infection group of rats and was also effective in S. stercoralis DNA amplification in patients´ stool samples with previously confirmed strongyloidiasis by parasitological and real-time PCR tests. Conclusions/Significance: Our Strong-LAMP assay is an useful molecular tool in research of a strongyloidiasis experimental infection model in both stool and urine samples. After further validation, the Strong-LAMP could also be potentially applied for effective diagnosis of strongyloidiasis in a clinical setting. [ABSTRACT FROM AUTHOR]

During the period 2012-2016, distribution of the common hamster, Cricetus cricetus, was monitored in Bohemia, Czech Republic. Between the harvest and subsequent field ploughing, i.e. in August and September, we visited all regions in which occurrence of the species after 1990 was reported in previous studies. There, in every square of the K. F. M. E. mapping grid we checked at least four harvested crop fields, i.e., cereals (preferably wheat and barley), sometimes also alfalfa and various vegetables, and examined also field balks and road ditches. In addition, during all parts of the year we recorded hamster road casualties. Also some personal reports by experienced co-workers were used. Altogether, we recorded hamster presence in 290 sites covering 75 K. F. M. E. squares. The area of the hamster occurrence in Bohemia consists of one big and one small sub-areas, most probably isolated from each other. They form a strip ca. 250 km long and mostly ca. 30-60 km wide. It runs from the lowlands along lower reaches of the Ohře river, through the Prague Plateau, lowlands along the Labe river up to the Svitavská pahorkatina Upland. The easternmost confirmed localities were near Svitavy. The altitude of most of the hamster localities varies between 130 and 300 m, in the Pražská plošina Plateau up to 400 m (altitudes of four exceptional localities near Svitavy are between 462 and 503 m). In some lowland regions of Bohemia the hamster is still common and locally abundant. The hamster prefers deeper soils, mostly various types of chernozem, luvisol and cambisol. It avoids moist places and extensive fields of maize and rape. All our hamster localities are situated in plots of the open agricultural landscape covering several tens of square kilometers. The hamster is also able to inhabit ruderal places in the periphery of villages and towns. During the second half of August and first half of September, the number of dead hamsters in roads increased considerably, suggesting that the traffic causes a not inconsiderable portion of hamster mortality. [ABSTRACT FROM AUTHOR]

While most mammal populations show equalized sex ratios in their offspring, some species reveal deviations as a reaction to environmental circumstances. The recent study focuses on mortality, dispersal and biased sex ratio in the offspring of the edible dormouse (Glis glis) and their influence on next year's subadult population. Between 2002 and 2008 a male biased sex ratio in the offspring but an almost equal sex ratio of next year's subadult population has been found. Our results reveal that this deviation from the 1:1 sex ratio compensates a higher mortality rate of young males. The data used for this study were obtained from a mark and recapture project of monitoring the population biology of the edible dormouse performed north-east of Frankfurt/Main, Germany. [ABSTRACT FROM AUTHOR]

Indian crested porcupine (Hystrix indica) is a member of the family of Old World porcupines (Hystricidae). Its body is covered with multiple layers of quills, which serve for warning and attack if animal is threatened. However, the literature data on injuries caused by Indian crested porcupine are absent. We describe pathomorphological lesions in an Indian crested porcupine from the Ljubljana Zoo, which died after a fight with a younger male that caused a perforative quill injury of the thoracic wall, followed by septicaemia. Macroscopic, microscopic and bacteriological findings were detailed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the antidepressant-like effect of N-(benzo[d] thiazol-2-yl)-3- ethoxyquinoxalin-2-carboxamide 6k, a 5-hydroxytryptamine type 3 (5-HT3) receptor antagonist using rodents behavioral battery tests. Materials and Methods: 6k screening was performed with behavioral assays for depression-like forced swim test (FST) at several single doses (0.25-4 mg/kg, intraperitoneal injection (i.p.)) to test the potency of 6k, in which 2 and 4 mg/kg doses were found to be most effective and hence, in further behavioral assays including mechanistic model like 5-hydroxytryptophan (5-HTP)-induced head twitches was performed in mice at acute doses of 6k (2 and 4 mg/kg, i.p.). Furthermore, olfactory bulbectomy (OBX), a surgical model-induced behavioral alterations was performed in rats, and the effect of 6k administered orally (2 and 4 mg/kg, p.o.) after subchronic treatment for 14 days starting from day 15 of postsurgery was examined by percent sucrose preference test and modified open field test (OFT). Results: 6k (1, 2, and 4 mg/kg, i.p.) reduced the immobility time and increased the swimming behavior in FST without affecting the baseline locomotor score showing antidepressant-like effect. 5-HTP-induced head twitch response was potentiated by 6k (2 and 4 mg/kg, i.p.), which indicated rise in the serotonergic neurotransmission in the brain. 6k (2 and 4 mg/kg, p.o.) showed anti-anhedonia effect by increasing the sucrose consumption and reversed the behavioral alterations when exposed to modified open field in OBX rats after subchronic treatment for 14 days, thus exhibiting antidepressant-like effect. Conclusion: 6k attenuated the behavioral derangement in rodents-based behavioral battery tests for depression, indicating antidepressant-like potential. [ABSTRACT FROM AUTHOR]

Highlights: [•] Different tests to evaluate responses of cells to propolis and radiation were used. [•] Radio-protective capacity of propolis against radio-induced damage was observed. [•] Different modality of cell death due to propolis and/or radiation was observed. [•] Validation use of propolis for prevention against ionizing radiation is suggested. [ABSTRACT FROM AUTHOR]

Naked mole-rats occur in large colonies where usually a single queen monopolizes reproduction. Queen succession occurs from within usually as a result of aggressive encounters with subordinate females that queue for reproductive succession following colony instability, which inevitably results in death of either the queen or the challenging conspecific. We monitored a queen succession following the death of the breeding male in a colony of the naked mole-rat, Heterocephalus glaber, prior to, during as well as after replacement of the original breeding female. The response of the pituitary luteotrophs was investigated in the non-reproductive females during this period of instability by the administration of endogenous gonadotrophin releasing hormone (GnRH) and evaluating the subsequent luteinising hormone (LH) response in the blood. Larger and older non-breeding females engaged in aggressive encounters that culminated in death. The new breeding successor which arose from within the colony was a large female who continued to procreate. The six non-breeding females that were killed during reproductive takeover were larger and older females which exhibited elevated basal circulating LH concentrations as well as increased pituitary sensitivity as measured by the amount of releasable LH to an exogenous GnRH challenge. By contrast, non-breeding females that survived the succession were smaller and younger animals with reduced basal and GnRH challenged LH concentrations. Likewise, five non-breeding males which were heavier and older than those non-breeding males which survived were killed. These animals did not, however, show elevated basal or exogenous GnRH challenged LH concentrations when compared to the surviving males. The non-breeding animals of both sexes which survived the reproductive takeover event represented individuals which posed a minimal threat to the new successor and hence promoted the continuation of the marked reproductive skew that is prevalent in this highly inbred colonial subterranean hystricomorph. [ABSTRACT FROM AUTHOR]