Interaction between early in ovo stimulation of the gut microbiota and chicken host - splenic changes in gene expression and methylation.

BACKGROUND: Epigenetic regulation of the gene expression results from interaction between the external environment and transcription of the genetic information encoded in DNA. Methylated CpG regions within the gene promoters lead to silencing of the gene expression in most cases. Factors contributing to epigenetic regulation include intestinal microbiota, which in chicken can be potently modified by in ovo stimulation. The main aim of this study was to determine global and specific methylation patterns of the spleen under the influence of host-microbiome interaction. RESULTS: Fertilized eggs of two genotypes: Ross 308 and Green-legged Partridgelike were in ovo stimulated on d 12 of incubation. The injected compounds were as follows: probiotic - Lactococcus lactis subsp. cremoris IBB477, prebiotic - galactooligosaccharides, and synbiotic - combination of both. Chickens were sacrificed on d 42 post-hatching. Spleen was collected, RNA and DNA were isolated and intended to gene expression, gene methylation and global methylation analysis. We have proved that negative regulation of gene expression after administration of bioactive substances in ovo might have epigenetic character. Epigenetic changes depend on the genotype and the substance administered in ovo. CONCLUSION: Epigenetic nature of microbial reprogramming in poultry and extension of issues related to host-microbiome interaction is a new direction of this research.

Comparative analysis of cat bone marrow and adipose tissue cell cultures.

Cell culture transplantation is very promising in the treatment of various diseases. Cells obtained from a number of sources have been analysed to provide a basis for further studies in the area of regenerative medicine. The objective of the study was to compare morphological and phenotypic changes in cat adipose tissue and bone marrow cell cultures from the first to fifth passages. Adipose tissue and bone marrow were used to obtain cell cultures (coming from 3 cats) using standard methods with own modification. Phenotype changes were monitored by CD-marker identification and CD pan-keratin. The cytogenetic analysis was performed on 50 metaphase plates of cell cultures from the first to fifth passage. Cytogenetic assays showed that the adipose tissue cell culture (ATCC) at all passages was more stable than the bone marrow cell culture (BMCC).

Algorithm for establishing the time of death of a dog based on temperature measurements in selected sites of the body during the early post-mortem period.

Post-mortem measurements were made of the body temperature of dogs. The aim of the study was to evaluate and verify a reliable mathematical model that can be used to establish the time elapsed since the death of a dog during the initial post-mortem period at room temperature, using the eye (vitreous body), internal organs (heart, liver, kidney and lung), and rectum as sites for temperature measurement. The measurements were performed at six points in the body using an electronic thermometer in conjunction with a temperature probe. The method of temperature measurement is simple and does not cause perceptible macroscopic changes or disfigure the carcass. Multiple regression analysis was shown to be suitable for estimating the time elapsed from death to the discovery of the body for a period up to 12h post-mortem. The proposed multiple regression equation using body weight and the temperature at a specific site reduces manipulation of the carcass to a minimum and thus reduces error in establishing the time of death. The multiple regression model makes it possible to precisely estimate the time elapsed since the death of the animal.

Immunophenotypic characteristics and karyotype analysis of bone marrow-derived mesenchymal stem cells of rabbits during in vitro cultivation.

The aim of this study was to establish the immunophenotypic profile and karyotypic stability of bone marrow mesenchymal stem cells (MSCs) of rabbits at the early passages in vitro following the application of different methods of dissociation of cellular material. MSCs were obtained from the femur bone marrow of three clinically healthy rabbits under general anaesthesia. Bone marrow aspirate was seeded in Petri dishes and cultured in a CO2 incubator with 5% CO2 at 37.0oC using a standard procedure. Immunohistochemical detection of nuclear proteins, cytoskeletal proteins and cell adhesion were performed by immunohistochemical analysis and karyotype analysis of MSCs following the enzyme and chelating methods of dissociation of the cell monolayer. The results of the immunophenotypic analysis of rabbit bone marrow MSCs showed that at the first, seventh, twelfth, and eighteenth passages these cells express markers of mesenchymal, muscle, epithelial and nerve cells. The choice of the enzyme or chelating method of dissociation of a culture of rabbit mesenchymal stem cells affects their cytogenetic variability. Dissociation of the MSCs monolayer with ethylenediaminetetraacetic acid produces a cell culture with fewer quantitative and qualitative changes in the chromosome apparatus as compared to the enzyme method. Rabbit MSCs express markers of mesenchymal (vimentin, actin), muscle, epithelial and nerve (E-cadherin, N-cadherin) cells that are essential for differentiation of these cells. The chelating method of dissociation of a culture of rabbit mesenchymal stem cells, using ethylenediaminetetraacetic acid during cultivation, is more advantageous than the enzyme method of dissociation because it leads to less cytogenetic variability.

Sister chromatid exchange in Greenleg Partridge and Polbar hens covered by the gene-pool protection program for farm animals in Poland.

A basic assay that detects genotoxic DNA damage disrupting DNA replication and repair mechanisms is the sister chromatid exchange test. The frequency of sister chromatid exchanges was analyzed in chromosomes of the following hen breeds: Greenleg Partridge and Polbar. Chromosome preparations were obtained from our in vitro culture of peripheral blood lymphocytes stained using the fluorescence plus Giemsa (FPG) technique. The sister chromatid exchange (SCE)/cell mean of the hens under analysis was 7.83 ± 1.76 (7.22 ± 1.70 in the Greenleg Partridge and 8.43 ± 1.61 in the Polbar population). Statistically significant differences were identified between the hen breeds. A higher mean number of SCE/cell was observed in the group of hens producing fewer eggs (8.55 ± 1.51) compared with the group with a better egg yield (7.10 ± 1.65). The differences were statistically significant. Additionally, SCE frequency in the first, second, and third chromosome was analyzed in detail. The highest number of SCE was observed in the first and the lowest in the third chromosome. The SCE distribution in the particular regions of the analyzed chromosomes was also studied. The most numerous exchanges were observed in the proximal region, followed by the interstitial and distal areas.