Gray Rats Research Articles

Влияние содержания действующего вещества в родентицидном средстве на эффективность дератизационных обработок

House mice, gray rats and other mouse-like rodents pose a threat to human health and cause significant damage to its activities. Despite significant advances in deratization practice, rodent control currently remains a significant problem, since these biological species have a unique genetic ability to rapidly recover and increase their numbers. The rodent control program should be based on data on the ecology, behavior and preferences of rodents, their sensitivity to active substances, the specific situation of a certain object and territory. Each species has its own characteristics. It is necessary to take into account species preferences when developing the composition and form of application of rodenticidal baits. It is important to ensure the achievement of target values in the consumption of the product by rodents, its effectiveness, safety in relation to non-target species and safety during its placement and use. It is necessary to take into account what concentration of the active substance (DV) for rodents will be fatal, how much rodenticidal bait will be required for their death and for how long this amount of bait will be eaten by them. The effectiveness of the conducted deratization treatments is directly influenced by the content of the active substance in the applied rodenticidal agent. The analysis of the effectiveness of rodenticidal baits with different contents of the active substance bromadiolone in relation to house mice and gray rats showed that with a decrease in the concentration of DV in the bait, the period from the beginning of its eating to the onset of irreversible changes in the body of rodents leading to their death occurs. The placement of baits during deratization treatments should take place taking into account the species characteristics of rodents. In terms of body weight, the amount of absorbed DV by the body of a house mouse in comparison with a gray rat when eating rodenticidal bait is significantly higher, which is observed in the average daily and total intake. But in quantitative terms, gray rats consume significantly more bait. For the death of a house mouse, an average of about 8 g of bait is required with a bromadiolone content of 0.005?%, and the minimum amount was 3.2 g. For a gray rat, the average amount of bait was 32.4 g, and the minimum ~ 10 g. Taking into account these data, the amount of bait placed at the facility will vary from the number of rodents and the feedability of baits. A lower content of DV in baits contributes to an increase in their consumption during deratization treatments. With a high number of rodents, the amount of bait placed must be multiplied. Keywords: synanthropic rodents, gray rat, house mouse, deratization measures, anticoagulants, bromadiolone.

Key Enzymes of the Serotonergic System - Tryptophan Hydroxylase2 and Monoamine OxidaseA - In the Brain of Rats Selectively Bred for a Reaction toward Humans: Effects of Benzopentathiepin TC-2153.

At the Institute of Cytology and Genetics (Novosibirsk, Russia) for over 85 generations, gray rats have been selected for high aggression toward humans (aggressive rats) or its complete absence (tame rats). Aggressive rats are an interesting model for studying fear-induced aggression. Benzopentathiepin TC-2153 exerts an antiaggressive effect on aggressive rats and affects the serotonergic system: an important regulator of aggression. Theaim of this study was to investigate effects of TC-2153 on key serotonergic-system enzymes- tryptophan hydroxylase2 (TPH2) and monoamine oxidaseA (MAOA)- in the brain of aggressive and tame rats. Either TC-2153 (10 or 20mg/kg) or vehicle was administered once intraperitoneally to aggressive and tame male rats. TPH2 and MAOA enzymatic activities and mRNA and protein levels were assessed. The selection for high aggression resulted in upregulation of Tph2 mRNA in the midbrain, of the TPH2 protein in the hippocampus, and of proteins TPH2 and MAOA in the hypothalamus, as compared to tame rats. MAO enzymatic activity was higher in the midbrain and hippocampus of aggressive rats while TPH2 activity did not differ between the strains. The single TC-2153 administration decreased TPH2 and MAO activity in the hypothalamus and midbrain, respectively. The drug affected MAOA protein levels in the hypothalamus: upregulated them in aggressive rats and downregulated them intame ones. Thus, this study shows profound differences in the expression and activity of key serotonergic system enzymes in the brain of rats selectively bred for either highly aggressive behavior toward humans or its absence, and the effects of benzopentathiepin TC-2153 on these enzymes may point to mechanisms of its antiaggressive action.

Evaluation of antihypoxic effects of therapeutic breathing mixtures with high argon content on the example of acute blood loss in laboratory animals: a preclinical randomized experimental study

Background. According to the hypothesis of the study, the therapeutic efficacy of measures to treat hypoxic (ischemic) emergencies can be significantly increased by using an artificial gas mixture with normal or increased oxygen content and a high content of argon, being bioactive despite its chemical inertness.Objective. To experimentally evaluate the antihypoxic effects of argon on the example of acute massive blood loss in experimental animals.Methods. The study was carried out on 72 albino male gray rats with a baseline body weight of 220–250 g. The experiments were performed at the premises of the Konstantinov St. Petersburg Nuclear Physics Institute of the Kurchatov Institute and the Smorodintsev Research Institute of Influenza (Russia). Prior to the experiment, the animals were quarantined for 2 weeks in the vivariums of the performing organizations. Acute massive blood loss in rats was formed by taking blood (12 ± 1% of body weight on average) using syringe method by transcutaneous cardiac puncture. Rats were randomized into 3 groups (24 individuals each) depending on the gaseous medium where the animal was placed after artificial blood loss. Composition of the applied gaseous medium in the comparison groups: medium No. 1 — oxygen 21% vol.; argon — 30% vol.; nitrogen — the rest; medium No. 2 — oxygen 21% vol.; argon — the rest; medium No. 3 (control) — air. The postoperative follow-up (post-conditioning) for 8 hours involved assessing and recording the following indicators: survival/lethality rates; recovery rates (anesthesia recovery, somatic mobilization); clinical symptoms of possible intoxication with the gas mixture during inhalation exposure. The surviving animals were then monitored for 4 days to evaluate their health and behavioral performance. Upon completing the observation period, the animals were euthanized.Results. After artificially-induced blood loss, all the non-survivors died within 1.5–8 hours after the operation. In group 1 (post-conditioning in medium No. 1), the lethality of laboratory animals amounted to 4 individuals out of 24 (16%); in group 2 (post-conditioning in medium No. 2) — 2 individuals out of 24 (8%). In the control group, the lethality rate was significantly higher — 10 animals out of 24 (42%). The surviving animals demonstrated no lethality or morbidity within 4 days after the exposure. Analysis of outcomes between experimental groups and controls revealed that the significance of differences in the lethality index between group 1 and control (by Fisher’s two-sided criterion) comprised p = 0.06; between group 2 and control — p = 0.017. When the statistical “power” of the experimental group was increased (by combining samples 1 and 2), the significance of differences in outcomes in this group compared to the control accounted for p < 0.001.Conclusion. The conducted studies confirmed the hypothesis about the pronounced antihypoxic effect of argon, which significantly increased the survival rate of experimental animals after massive artificially-induced blood loss.

A Principal Components Analysis and Functional Annotation of Differentially Expressed Genes in Brain Regions of Gray Rats Selected for Tame or Aggressive Behavior.

The process of domestication, despite its short duration as it compared with the time scale of the natural evolutionary process, has caused rapid and substantial changes in the phenotype of domestic animal species. Nonetheless, the genetic mechanisms underlying these changes remain poorly understood. The present study deals with an analysis of the transcriptomes from four brain regions of gray rats (Rattus norvegicus), serving as an experimental model object of domestication. We compared gene expression profiles in the hypothalamus, hippocampus, periaqueductal gray matter, and the midbrain tegmental region between tame domesticated and aggressive gray rats and revealed subdivisions of differentially expressed genes by principal components analysis that explain the main part of differentially gene expression variance. Functional analysis (in the DAVID (Database for Annotation, Visualization and Integrated Discovery) Bioinformatics Resources database) of the differentially expressed genes allowed us to identify and describe the key biological processes that can participate in the formation of the different behavioral patterns seen in the two groups of gray rats. Using the STRING- DB (search tool for recurring instances of neighboring genes) web service, we built a gene association network. The genes engaged in broad network interactions have been identified. Our study offers data on the genes whose expression levels change in response to artificial selection for behavior during animal domestication.

Physicochemical and Toxicological Studies of the Polymorphic Modifications of the Rodenticidal Substance “Chlorophacinone”

The results of studies of the polymorphism of the rodenticidal substance 2-[(4-chlorophenyl)phenylacetyl]-1H-indene-1,3(2H)-dione “chlorophacinone”, which has an anticoagulant mechanism of action, are presented. Methods for the synthesis of two new polymorphic forms (III and IV) have been established, for which data from physicochemical studies (IR, XRD) and information on the biological activity (toxicity) of polymorphs are given. Both forms crystallize in the monoclinic crystal system with space group P21/с and the following unit cell parameters: a = 16.698(1) Å, b = 5.632(1) Å, c = 20.253(2) Å, β = 109.65(1)° for III; and a = 9.853(1) Å, b = 9.041(1) Å, c = 20.474(1) Å, β = 97.322(3)° for IV. Polymorphic form IV with a toxicity parameter DL50 (gray rats) of 0.47 mg/kg has the highest biological activity versus 2.74 mg/kg for the less active form III. A method of identification of the most active form (IV) by IR spectroscopy was proposed.

Hippocampal Volume and the Spectrum of Metabolites in Adult Gray Rats Rattus norvegicus Selected for Different Attitudes toward Humans and Exposed to Early Social Instability

Hippocampal Volume and the Spectrum of Metabolites in Adult Gray Rats Rattus norvegicus Selected for Different Attitudes toward Humans and Exposed to Early Social Instability

Анализ действия приманок с разным содержанием действующего вещества бромадиолона в отношении серых крыс

Gray rats occupy a significant share in the number of synanthropes living next to humans. The fight against them is difficult, due to their high adaptability, as well as the risk of poisoning of non-target wild and domestic animals. Insufficiently organized deratization measures lead to an increase in the number of rodent populations and their settlement of new adjacent territories. Gray rats belong to the species of mouse-like rodents resistant to the action of many factors, including developing resistance to the effects of rodenticidal baits based on anticoagulants. Experimental studies have shown that the eating of at least 50 % of the daily requirement of baits containing 0,005 and 0,0025 % of the concentration of DV bromadiolone by gray rats during one day can cause 1 % death. When analyzing the results obtained when feeding baits, it was found that for the death of gray rats, the maximum dose was 100 mg/ kg, and the minimum was 6,88 mg/kg. Gray rats in conditions of free access to food and bait can consume up to 0,7 g of rodenticidal agent to achieve a lethal effect, but it will be enough for individuals to eat about 40 g for this.

Transcription Factors as Important Regulators of Changes in Behavior through Domestication of Gray Rats: Quantitative Data from RNA Sequencing.

Studies on hereditary fixation of the tame-behavior phenotype during animal domestication remain relevant and important because they are of both basic research and applied significance. In model animals, gray rats Rattus norvegicus bred for either an enhancement or reduction in defensive response to humans, for the first time, we used high-throughput RNA sequencing to investigate differential expression of genes in tissue samples from the tegmental region of the midbrain in 2-month-old rats showing either tame or aggressive behavior. A total of 42 differentially expressed genes (DEGs; adjusted p-value < 0.01 and fold-change > 2) were identified, with 20 upregulated and 22 downregulated genes in the tissue samples from tame rats compared with aggressive rats. Among them, three genes encoding transcription factors (TFs) were detected: Ascl3 was upregulated, whereas Fos and Fosb were downregulated in tissue samples from the brains of tame rats brain. Other DEGs were annotated as associated with extracellular matrix components, transporter proteins, the neurotransmitter system, signaling molecules, and immune system proteins. We believe that these DEGs encode proteins that constitute a multifactorial system determining the behavior for which the rats have been artificially selected. We demonstrated that several structural subtypes of E-box motifs—known as binding sites for many developmental TFs of the bHLH class, including the ASCL subfamily of TFs—are enriched in the set of promoters of the DEGs downregulated in the tissue samples of tame rats’. Because ASCL3 may act as a repressor on target genes of other developmental TFs of the bHLH class, we hypothesize that the expression of TF gene Ascl3 in tame rats indicates longer neurogenesis (as compared to aggressive rats), which is a sign of neoteny and domestication. Thus, our domestication model shows a new function of TF ASCL3: it may play the most important role in behavioral changes in animals.

СРАВНИТЕЛЬНАЯ ВЕТЕРИНАРНО-САНИТАРНАЯ ОЦЕНКА РАЗЛИЧНЫХ ПРЕПАРАТИВНЫХ ФОРМ РОДЕНТИЦИДНЫХ ПРИМАНОК, ПРИМЕНЯЕМЫХ В ЖИВОТНОВОДЧЕСКИХ ОБЪЕКТАХ

The article presents a comparative veterinary and sanitary assessment of various preparative forms of rodenticidal baits for the control of synanthropic (mouse-like) rodents. The rodenticidal activity of deratization agents in the form of loose grain bait, paper bags, mineral and gelatin capsules were studied in laboratory conditions. New knowledge about the bait consumption by grey rats depending on their shape has been obtained. The variety of forms of rodenticides makes it possible to select the formulations of baits taking into account production features, natural and climatic characteristics and the availability of food resources at livestock facilities, as well as increase the attractiveness of the bait, prevent pollution of environmental objects with anticoagulant poisons and exclude possible poisoning of non-target animal species.

Differential expression of 10 genes in the hypothalamus of two generations of rats selected for a reaction to humans.

Individual behavioral differences are due to an interaction of the genotype and the environment. Phenotypic manifestation of aggressive behavior depends on the coordinated expression of gene ensembles. Nonetheless, the identification of these genes and of combinations of their mutual influence on expression remains a difficult task. Using animal models of aggressive behavior (gray rats that were selected for a reaction to humans; tame and aggressive rat strains), we evaluated the expression of 10 genes potentially associated with aggressiveness according to the literature: Cacna1b, Cacna2d3, Drd2, Egr1, Gad2, Gria2, Mapk1, Nos1, Pomc, and Syn1. To identify the genes most important for the manifestation of aggressiveness, we analyzed the expression of these genes in two generations of rats: 88th and 90th. Assessment of gene expression levels was carried out by real-time PCR in the hypothalamus of tame and aggressive rats. This analysis confirmed that 4 out of the 10 genes differ in expression levels between aggressive rats and tame rats in both generations. Specifically, it was shown that the expression of the Cacna1b, Drd2, Egr1, and Gad2 genes does not differ between the two generations (88th vs 90th) within each strain, but significantly differs between the strains: in the tame rats of both generations, the expression levels of these genes are significantly lower as compared to those in the aggressive rats. Therefore, these genes hold promise for further studies on behavioral characteristics. Thus, we confirmed polygenic causes of phenotypic manifestation of aggressive reactions.

Adolescent oxytocin treatment affects resident behavior in aggressive but not tame adult rats

There are indications that exposing adolescent rodents to oxytocin (OT) promotes social activity and reduces anxiety in adulthood. Adult male gray rats selected for elimination and enhancement of the aggressive response to humans, when exposed to OT, showed divergent changes in the resident behavior towards the intruder. It could be assumed that adolescent administration of both OT and antagonist of OT receptor (OTR) would also have different long-term effects on resident behavior and startle reflex in adult aggressive and tame rats. The aim of this work is to study the long-term effects of adolescent administration of both OT and antagonist of OT receptor (OTR) on resident behavior and startle reflex in adult tame and aggressive male gray rats. Starting at the age of 28 days, the animals received nasal applications of 5 μL of oxytocin solution (1 μg / μL) or saline for 5 days (daily). At the age of two months, the acoustic startle amplitude was assessed in two series of 5 acoustic stimuli. The resident-intruder test was performed one week later. Antagonist of OT receptor l-368,899 was administered intraperitoneally (i.p.) once at a dose of 5 mg/kg at the age of 30–33 days. Subsequent startle reflex tests were performed 20 days later, at the age of 50–53 days. A week later, the resident-intruder test was performed on the same rats. The startle amplitude in aggressive rats of the control group (in two series of acoustic stimuli) and those having received saline (in the first series) was larger than in the corresponding tame groups. Oxytocin and saline solutions did not significantly affect the startle amplitude compared to control animals. After saline administration, the attack latency in tame rats was longer than in aggressive rats (P <0.05). Oxytocin treatment caused a prolongation of this period in aggressive males compared with control animals receiving saline solution (P <0.01). In addition, oxytocin administration in aggressive males caused an increase in the time of social behavior, which did not include aggressive and same-sex behavior, as compared with the corresponding control animals (P <0.05). Exogenous oxytocin receptor antagonist (l-368,899) did not affect the startle amplitude and behavior in the resident-intruder test in aggressive and tame male rats. Adolescent OT treatment causes a prolongation of both the attack latency and social behavior in the resident-intruder test in adult aggressive male rats, but does not affect these parameters in tame rats.

Umbilical cord-derived mesenchymal stem cells in treatment uterine scar

Background & Aim The scar on the uterus is one of the most formidable problems affecting reproductive function, that an obstetrician-gynecologist faces with. The search of the way to improve the quality of the uterine scar is extremely relevant. An experimental study aimed at comparing the tissue effects of Human MSC in the area of the wound on the uterus after surgery was carried out in rats. Methods, Results & Conclusion Methods: female albino grey rats of the Wistar line were included and operated in experiment. Model: trauma to the unchanged uterine muscle, applying with a scalpel. After suturing the uterine horns, direct intramuscular injection of MSCs (a dose of 1 × 107 cells in 1mL of 0.9% saline) (n=10, MSCs group) was injected the left-horns along uterine scar. The right horns of the uterus were not affected after suturing (n=10, control group). On the 15th day after transplantation, the rats were euthanized and serial sections of uterine tissues containing the operative region were prepared. Methods The distribution of MSCs in the operated uterine horns of rats was evaluated by immunohistochemistry. Slides were deparaffinized and rehydrated according to a standard protocol. Before hybridization, the DNA denaturation was performed in 70% formamide at 74°C for 4 minutes. Hybridization was performed for 5 hours at 41°C with hybridization mix containing Cy3-labelled probe for human pericentromeric DNA. Image acquisition was performed using an Olympus FV3000 confocal microscope (Nikon, Japan). The cells were sectioned in z-axis with a 0.7 M interval. For large-scale 2D imaging a MatLab function built in Olympus FV 3000 software was used. Results Human MSC cells were detected in the left horn (where MSC had been injected) during all the 15 days of the experiment. They localized presumably in mesenchymal tissues – vessels perivascular areas, circular and longitudinal muscles. In the right horn, the cells were also detected but the number of cells was much lower. Most of hybridization signals were revealed in the nucleus. Therefore these cells can be considered as human MSC. However some of the signals were detected in the cytoplasm. These cells are most likely of the recipient origin probably the macrophages or other cells capable of phago- or endocytosis. Conclusions The data obtained can expand the possibilities of pathogenetically substantiated prevention of uterine scar inferiority. The scar on the uterus is one of the most formidable problems affecting reproductive function, that an obstetrician-gynecologist faces with. The search of the way to improve the quality of the uterine scar is extremely relevant. An experimental study aimed at comparing the tissue effects of Human MSC in the area of the wound on the uterus after surgery was carried out in rats. Methods: female albino grey rats of the Wistar line were included and operated in experiment.

LABORATORY BASED OF SURVEILLANCE FOR LEPTOSPIROSIS IN LVIV OBLAST, UKRAINE

LABORATORY BASED OF SURVEILLANCE FOR LEPTOSPIROSIS IN LVIV OBLAST, UKRAINE

Determination of the systemic colorimetric parameters of unmasking rats at videor registration in urban conditions

The relevance of the article is determined by threats to biobesopathy in urban conditions, which can be created by loss of control over the population of rats (Rattus norvegicus). The purpose of the study is to determine of the system colorimetric parameters of unmasking rats with video recording in urban conditions. Methods of solution. This goal is achieved by mathematical modeling of systemic colorimetric parameters of the rat’s protective coloration. Exceeding these values over similar background values of the urban landscape fragments allows unmasking animals. Modeling is performed using new class of models – discrete models of dynamic systems, based on the actual image material Rattus norvegicus. Images taken from the Internet and processed using MatLab package. Results. A values combination of the colorimetric parameters are found that can play the role of the system colorimetric parameters, which is the most pronounced measure of the variegation of the Rattus norvegicus protective coloration. This value is entered in a specially created database, which contains information about the spatial coordinates of this segment in the image. The value of the specified color parameter for each segment during image processing is denoted by a conventional color. Placing a segment on an image is determined by its spatial coordinates entered in the database. The effectiveness of SCP using was verified by image processing of the rat against the background of a fragment of the urban landscape. Conclusions. The results of image processing of the rat show the effectiveness of contrast increasing of the silhouette of the animal, which increases the efficiency of video recording of numbers and migrations of the gray rats in urban conditions.

APPLICATION OF PCR FOR SURVEILLANCE OF NATURAL FOCI OF ESPECIAL DANGEROUS PATHOGENS

Objective: Study the advantages of using the PCR method for monitoring of natural foci within the EDP surveillance system.Introduction: Natural foci of especially dangerous pathogens (EDP) (tularemia, leptospirosis, anthrax, tick-borne infections) are known in Lviv oblast for more than 50 years. An integral part of the epidemiological surveillance of these infections is the monitoring of environmental objects that can detect the circulation of pathogens in natural biotopes. Identification and studying of the activity of natural foci of EDP in the territory of Lviv oblast in previous years was conducted using classical laboratory and epidemiological methodsMethods:Since 2015 in the EDP laboratory are conducted investigations of field materials (mouse-like rodents, ixodic ticks, gray rats, surface water bodies, wild birds dungs, soil) during the monitoring process of the EDP natural foci. From 2015 to 2017 samples of field materials were investigated in order to identify specific DNA regions of causative agents of tularemia, anthrax, leptospirosis, Q-fever, Lyme borreliosis, etc., using the «Primer designTM genesig», «GENEKAM Biotechnology AG», «MO BIO Laboratories, Inc», «Analytic Jena AG» kits, which were provided within the Cooperative Biological Engagement Program (CBEP), and «Amplisens» kits. During this period samples were analyzed from 299 mouse-like rodents, 7325 ixodic ticks, 128 open water reservoirs, 51 wild birds dung, 92 soil samples and 17 gray rats.In addition, enzyme-linked immunosorbent assay (ELISA) was used. For immunoserological monitoring selected serum samples of 80 people living in enzootic territories were used. Currently, 40 human samples were investigated for the presence of IgM and IgG antibodies using the “Serion ELISA classic Francisella tularensis IgG/IgM".Results:According to the results of the research that was conducted in previous years it was revealed that in the territory of Lviv oblast there are stable natural foci of tularemia, leptospirosis, tick-borne infections (Lyme borreliosis, tick-borne encephalitis) present. The main reservoirs of pathogens are 5-6 species of small mouse-like rodents and gray rats who are carriers of two dominant species of ixodic ticks. Live cultures of tularemia and leptospirosis were isolated from these types of reservoirs and carriers and positive results of immunoserological analysis were found. Tularemia antigen was detected in 29.2% of ticks samples (D. reticulatus mainly), causative agents of Lyme borreliosis D. reticulatus was detected in 17.3% of ticks and I.ricinusin was present in 8.0% of ticks. During the serological investigation of mouse-like rodents antibodies against F.tularensis were detected in 6.5% of samples, antibodies against leptospira in 6.7%, and antibodies against borrelia from 14.6% to 27.7%.During the monitoring period of burial places of animals killed from anthrax on the territory of the oblast where classical laboratory methods were used, B.anthracis was not detected. However, due to the ability of the pathogen to maintain its pathogenic properties for a long time, monitoring of such areas will be relevant in the future.According to analysis of mouse-like rodents, ticks, samples of surface water bodies, wild birds dung, soil and gray rats were received 3.18% positive samples that confirmed the presence of F.tularensis, 9.74% positive samples of pathogenic Leptospira spp, 20.75% positive samples of B. burgdorferi s.l.. Results of DNA detection of tularemia, leptospirosis and Lyme borreliosis were obtained on already known enzootic territories as well as on new ones. During the investigation of soil samples collected from burial places of animals, DNA of B.anthracis were not detected. Also, results of PCR-tested samples of ticks and rodents were negative and did not confirm the presence of C. burnetii. Based on data received from PCR analysis, anti-epidemic measures were carried out in places where positive results were found: additional acaricidal treatment of areas of ticks breeding, deratization measures and educational work with the population. The investigation of 40 serum samples collected from people living in the enzootic territory gave negative results, but the work continues.Conclusions:PCR methodology provides a possibility to monitor the natural foci of EDP at a fundamentally new level. Its requires less time for getting results if compared to classical methods, the level of biorisks during the work is lower, and it is possible to conduct samples at the same time to detect several pathogens.

Влияние ультразвука на поведение серых крыс

The influence of ultrasound on the behavior of Brwon Rats (Rattus norvegicus, Berkenhout, 1769) in the open field test is considered in the article. Animals were exposed to ultrasound at 22 kHz and simultaneously at 50-60 kHz for 24 hours. The indices of the activity of the individual in the open field were compared before and after the experiment. As a result of the tests, multidirectional changes in motor activity (number of columns and intersected squares), frequency of defecations and duration of grooming were revealed. The results obtained show that the behavior of most rats after exposure to ultrasound tended to change, but these data did not differ significantly. Thus, the use of the Quadblaster QB-4 and Filin ultrasound scanners at a frequency of 22 kHz and 50-60 kHz for 24 hours did not cause a significant change in the behavior of the animals, and therefore their use as repellents for gray rats appears to be ineffective.

Сравнительный анализ особенностей решения задачи на выбор отверстия, соответствующего размерам тела у сцинков Tiliqua gigas и крыс Rattus norvegicus

The article presents a comparative psychological analysis of the peculiarities of solving the problem of choosing a hole corresponding to the size of the body in blue-tongued skinks and gray rats. In the course of the study, in the framework of which the animals had to solve the problem of obtaining bait, through the holes corresponding to the size of the body. In the course of the experiment, the limits of the bodies of animals changed: natural or enlarged. It was found that both types of animals are able to solve the problem. During experimental series, the skinks learned to choose a large hole that is permeable to the enlarged limits of their bodies. Rats are able to learn the empirical regularity of the ratio of the limits of their own bodies and the limits of environmental objects, which allows them to flexibly modify their behavior in accordance with new situations, both in the case of changes in the characteristics of their bodies and in the changes in the characteristics of external objects. Based on these data, we conclude that the cognitive abilities of skinks and rats vary considerably: unlike skinks, rats are able to learn how to fit their body size and hole size, and then without additional training, use this skill flexibly in new situations.

К вопросу о гельминтах серых крыс города Омска

Gray rat is one of the many species of rodents, prone to Sinanthropus, omnivorous and rapid fertility. Living in close proximity to human, rats are a real danger to people, because they can serve as reservoirs and sources of pathogens of various diseases of viral, bacterial and parasitic nature. Infection of human occurs through direct contact with the corpses of the fallen within the dwelling rats, food, contaminated by their faeces, through surfaces, that come into contact with sick animals, and indirectly through domestic cats and dogs. The study of gray rat’s helminthofauna is one of the important tasks in the assessment of helminth infections spread in Omsk. The aim is to study the species composition of gray rats helminths in Omsk. Objectives are: to determine the species composition of gray rats helminths; set the extensiveness of (E.I.) and intensity (I.I.) of invasions. The charges of helminths from 18 rats were materials for their own research. Catching rats was carried out on the territory of clinical hospital of the building 2 of Institute of Veterinary Medicine of Omsk State Agrarian University name after P.A. Stolypin. An autopsy was carried out in rats according to the procedure for opening the helminthological full of K.I. Skryabin. Total helminths infestation of gray rats was 100%. 3 types of helminths were revealed in 18 individual gray rats. Among cestodes the Hymenolepis diminutive is widely distributed in the form of gray rats. The extensiveness invasion is 55.5%, with an average intensity of 4 units. Cestodes Rodentolepis straminea infected 33.3% of rodents with intensity of 5 units. Syphacia muris nematode was found in 33.3% of the individuals, the intensity of infection was 2.6 units. The findings have important economic significance and should be considered in the prevention work of veterinary, sanitary - epidemiological and health services.

Role of apoptosis genes in aggression revealed using combined analysis of ANDSystem gene networks, expression and genomic data in grey rats with aggressive behavior

Role of apoptosis genes in aggression revealed using combined analysis of ANDSystem gene networks, expression and genomic data in grey rats with aggressive behavior

Analysis of differential gene expression by RNA-seq data in brain areas of laboratory animals.

Computer analysis of gene expression in the nervous system plays a fundamental role in biology, genetics, and neurosciences. We studied molecular and genetic mechanisms of enhanced aggressiveness in comparison with tolerant behaviour using experimental animal models developed at the Institute of Cytology and Genetics SB RAS. Grey rats (Rattus norvegicus) have been subjected to selection during several generations in two directions &ndash; friendly, tolerant behaviour towards man (tame grey rats) and increased aggressive behaviour. We used samples from hypothalamus, mesencephalic tegmentum and periaqueductum grey matter from brain areas of grey rats genetically selected by behaviour in many generations. The set of computer tools and data processing pipelines helped to find genes and gene regulation patterns related to behaviour patterns. RNA - profiling experiments revealed the lists of differentially expressed genes in the contrast samples as well as differentially spliced isoforms. The gene ontology categories of protein transport, phosphoproteins, and nucleotide binding are presented together with categories of transmission of nerve impulses and neuron development were identified. Differential alternative splicing events found in the brain areas studied are statistically significant. We discuss role of alternative splicing events for neurospecific genes in behaviour patterns as well as extension of brain transcriptomics profiling.