Magdalena Gryzińska

Analysis of Age-Related Global DNA Methylation in Chicken

DNA methylation is an epigenetic modification that plays an important role in the normal development and function of organisms. The level of DNA methylation is species-, tissue-, and organelle-specific, and the methylation pattern is determined during embryogenesis. DNA methylation has also been correlated with age. The aim of this study was to determine the global DNA methylation levels and their correlation with age in the chicken, using a Polish autosexing chicken breed, Polbar. A quantitative technique based on an immunoenzymatic assay was used for global DNA methylation analysis. The results show increased global DNA methylation levels with older Polbar embryos. Global DNA methylation levels decrease with the age of hens in the postembryonic stage. This study expands the current knowledge of the Polbar epigenome and the general knowledge of the function of epigenetic mechanisms in birds.

Analysis of genetic variability in farmed and wild populations of raccoon dog (Nyctereutes procyonoides) using microsatellite sequences.

Abstract The aim of this study was to detect possible differences between farmed and wild-living raccoon dogs. Analysis of polymorphism in 15 microsatellite sequences led to the conclusion that raccoon dogs raised on Polish farms and wild raccoon dogs living in Poland are two genetically distinct groups of animals. Wild Polish raccoon dogs are genetically more similar to the population of wild animals from the Kaliningrad Region than to farmed animals. The analysis of microsatellite loci showed clear genetic differences between farmed and wild-living populations of raccoon dog, despite only 50 years of isolation of the two groups of animals. The farmed population was characterized by higher genetic variation than the wild-living population. On the basis of the analyses three microsatellite loci (INU014, Ren13J22 and Ren41D20) were proposed for determination of the origin of animals that have escaped from farms.

Analysis of cases of forensic veterinary opinions produced in a research and teaching unit

The aim of the study was to present the results of necropsies carried out in the years 2000-2014 in the Department of Pathological Anatomy, Faculty of Veterinary Medicine, University of Life Sciences in Lublin. The material used for the analysis consisted of expert opinions prepared on the basis of a decision by a judicial body to admit an expert opinion as evidence. An increase was observed in the demand for the services of veterinary forensic experts, beginning in 2006 and persisting through 2014. The response to the growing popularity of veterinary forensic examinations should be systematization of knowledge and exchange of experience, which would enable the further development of this interdisciplinary science.

THE EFFECT OF AMPHOTERICIN B ON THE LIFESPAN, BODY-SURFACE PROTEIN CONCENTRATIONS, AND DNA METHYLATION LEVELS OF HONEY BEES (Apis mellifera)

Abstract Three groups of caged bees were fed with sugar syrup (the control), sugar syrup supplemented with amphotericin B (AmB) in a dose of 0.5 mg/ml, and sugar syrup with AmB in a dose of 0.25 mg/ ml. Amphotericin B shortened the life span of the bees and reduced the level of global DNA methylation compared to the control, however, it increased the body-surface protein concentrations. In the hindguts of the bees, there were found AmB deposits. Honeybees appear to be a useful model for studying the side effects of anti-fungal AmB therapy. Among other things, epigenetic changes and senescence acceleration are considered to be the side effects of the therapy. Streszczenie Trzem grupom pszczół w klatkach podawano syrop cukrowy (grupa kontrolna), syrop cukrowy z dodatkiem amfoterycyny B (AmB) w dawce 0,5 mg/ml oraz syrop cukrowy z AmB w dawce 0,25 mg/ml. AmB wpływała na skrócenie długości życia pszczół oraz obniżała poziom globalnej metylacji DNA w porównaniu do grupy kontrolnej, jednocześnie zwiększała stężenie białek na powierzchni ciała. AmB odkładała się w jelicie tylnym pszczół. Pszczoła miodna okazała się użytecznym modelem dla badań efektów ubocznych terapii antygrzybiczej z zastosowaniem AmB. Między innymi, za efekty uboczne takiej terapii uważa się zmiany epigenetyczne i przyspieszenie procesów starzenia.

Age-dependent stability of nucleoli and global DNA methylation level in spermatocytes of the domestic horse (Equus caballus)

Abstract: The aim of the study was to determine the number and shape of nucleoli during meiosis in cells of the domestic horse. In addition, the level of global DNA methylation was determined using a quantitative technique for measuring the relative level of DNA methylation, modelled on an immunoenzymatic assay. The research was carried out on stallions belonging to two age groups (2 and 7 yr). In the cells of the 2-yr-old animals, the nucleoli were mainly of a regular shape and no fragmented nucleoli were observed. The cells of the 7-yr-old horses had a small percentage of regularly shaped nucleoli, and nucleoli with a fragmented structure were present. The study provides a basis for further research on epigenetic mechanisms in horses.

A very rare case of intersexuality in water mites of the genus Arrenurus Dugès, 1834 (Acari, Hydrachnidia)

In recent years, many authors have drawn attention to the fact that substances of anthropogenic origin introduced to the environment can disrupt the normal functioning of the endocrine system in animals, a phenomenon known as endocrine disruption. These substances are called endocrine-disrupting chemicals. It has been suggested that many cases of adverse changes in health (including the phenomenon of intersexuality) in a range of wildlife species are owing to exposure to endocrine disrupters. The main objective of this study was to report intersexuality in water mites of the genus Arrenurus. The intersex specimens of Arrenurus crassicaudatus Kramer, 1875 were more similar in their overall appearance to males than to females, but their external genital organ was more like the genital organ of a female than that of a male. Based on their morphological features and body measurements, intersex A. crassicaudatus individuals should be described as feminized males. The causes of intersexuality in aquatic invertebrates are still unclear and several mechanisms may be involved: parasitism, pollution affecting parasite function, and pollution directly causing the intersexuality seem to be the main factors increasing the frequency of the phenomenon.

Genetic Differentiation of Common Fox Vulpes Vulpes (Linnaeus, 1758) on the Basis of the Insulin-Like Growth Factor 1 (Igf1), Myosin-Xv (Myo15a) and Paired Box Homeotic 3 (Pax3) Genes Fragments Polymorphism

Abstract Single-nucleotide polymorphism (SNP) was analysed for selected fragments of three genes - insulin-like growth factor 1 (IGF1), myosin-XV (MYO15A) and paired box homeotic gene 3 (PAX3) - in farm and wild red foxes from two continents. The study was undertaken in order to verify whether the SNP characteristics of these genes enable farm-bred foxes to be distinguished from free-living foxes. The greatest number of changes were detected in the IGF1 gene. For each of the genes investigated specific SNP profiles characteristic only for farm foxes and only for wild foxes were noted. At the same time, specific SNP profiles were noted for wild foxes from North America and from Europe. The frequency of SNP (bases per SNP) in the gene fragments examined was 22 bp for IGF1, 34 bp for PAX3 and 56 bp for MYO15A. Single-nucleotide polymorphism is a very good molecular marker enabling characterization of nucleotide variation in the genes investigated between wild and farm individuals

Polymorphism of a DCT gene fragment sequence between the dog and the raccoon dog and its potential effect on binding of transcription factors – in silico analysis of a sequenced fragment

Domestication of dogs involved strong artificial selection. After their introduction into the human environment, dogs were exposed to factors that were not encountered in the wild. The skin and hair are barriers separating the organism from the environment, and melanin plays a significant role in their protective function. The study compared a fragment of the sequence of the DCT gene, which is involved in melanin synthesis, between two species: the dog, which is exposed to similar carcinogenic factors as humans, and the raccoon dog, a species related to the dog but less exposed to anthropogenic factors.A fragment of the DCT gene 443 base pairs in length was obtained. Two genotypes were distinguished within the raccoon dog population, differing in one nucleotide in the intron sequence (145A>G). Between the DNA profile of the dog and the consensus sequence of the raccoon dog, 18 polymorphic sites were found – 15 in the intron sequence and 3 in the exon sequence. One change in the exon (191G>A) caused an ami...

Single-nucleotide polymorphism of MC1R, ASIP, and TYRP2 genes in wild and farmed foxes (Vulpes vulpes)

Abstract: DNA mutations within genes associated with melanogenesis can affect melanin production, leading to dyschromias. Genes that are involved in synthesis of melatonin and may affect the color of skin are melanocortin 1 receptor (MC1R), agouti locus (ASIP), and tyrosinase-related protein-2 (TYRP2). In this study, SNP identification within ASIP, MC1R, and TYRP2 gene fragments in wild and farmed foxes (Vulpes vulpes) was performed. Nine mutations in the ASIP gene which allowed us to distinguish seven SNP profiles, fourteen mutations and five SNP profiles in the MC1R gene, and seven SNP profiles based on four polymorphic nucleotides in the TYRP2 gene were detected. Analyses of obtained profiles indicate that ASIP did not undergo mutations in the wild, and significant variability of SNP profiles was found for TYRP2, with specific haplotypes noted for farm foxes and American and European wild foxes.

POST-MORTEM ESTIMATION OF TIME OF DEATH OF DOGS BASED ON MEASUREMENTS OF KIDNEY TEMPERATURE IN COMPARISON WITH RECTAL TEMPERATURE

Abstract The subject of the study were dogs divided into two groups according to body weight: up to 10 kg and from 10 kg to 30 kg. The aim of the study was to determine the dynamics of the post-mortem decrease in rectal and kidney temperature. The temperature was measured on both sites at the same time using a thermometer connected to a computer, under constant environmental conditions of the necropsy room. In these animals, a higher temperature in the kidneys persisted for the duration of the study. Comparative analysis between mean differences in kidney and rectal temperature in small and large dogs showed the greatest temperature amplitude in the group of small dogs, both for the kidney and the rectum. The greatest decrease in temperature, 1.2°C, was noted for the kidney in small dogs between 4 and 6 hours after death. Analysis of the dynamics of the decrease in kidney and rectal temperature for both weight groups combined, and the difference in temperature between the kidney and the rectum in the time intervals analysed showed that in the first two hours the difference between kidney and rectal temperature did not exceed 0.5°C. Two hours after death the difference in temperature between the two measurement sites was about 0.5°C after which time dropped below 0.5ºC.