5-methylcytosine (5mC) is one of the most important epigenetic modifications. Its increased occurrence in regulatory sequences of genes, such as promoters and enhancers, is associated with the inhibition of their expression. Methylation patterns are not stable but are sensitive to factors such as the environment, diet, and age. In the present study, we investigated the effects of fungicide miconazole, both alone and in combination with the insecticide Mospilan 20SP, on the methylation status of bovine GSTP1, GSTA4, and AChE genes in bovine lymphocytes cultured in vitro. The methylation-specific PCR technique was used for the objectives of this study. We found that miconazole alone at concentrations of 1.25, 2.5, 5, 10, 25, and 50 µg/mL after 24 h exposure probably did not induce changes in methylation for all three genes analysed. The same results were found for the combination of pesticides at 24 h exposure and the following concentrations for each of them: 0.625, 1.25, 2.5, 5, and 12.5 µg/mL. Thus, we can conclude that the fungicide miconazole alone, as well as in combination with the insecticide Mospilan 20SP, was unlikely to cause changes to the methylation of bovine GSTP1, GSTA4, and AChE genes.

Background: Two hereditary eye disorders that are frequently observed in Collies and related breeds are Collie Eye Anomaly (CEA) and Progressive Retinal Atrophy (PRA). The main symptom of CEA is choroidal hypoplasia. It is associated with a 7.8 kb deletion in intron 4 of the NHEJ1 gene located on chromosome CFA7. Rod–cone dysplasia 3 (RCD3), an early-onset form of PRA, is associated with mutations in the PDE6A gene. Methods: Molecular diagnostic techniques were used in this study to identify genetic mutations linked to CEA and RCD3-type PRA in a subset of dog breeds. Australian Shepherds (n = 29), Border Collies (n = 9), Longhaired Collies (n = 27), and Shetland Sheepdogs (n = 10) provided a total of 75 DNA samples. Samples were collected by buccal swab or blood draw, and PCR and real-time PCR methods were used for processing. Results: Of the dogs in the studied breeds, 31 had the NHEJ1 gene mutation linked to CEA. Among these, 15 were homozygous recessive (affected), while 16 were heterozygous (carriers). None of the samples had any mutations in the PDE6A gene associated with RCD3-type PRA. Conclusions: Effective identification of carriers and affected individuals for CEA was made possible by PCR-based genetic testing, confirming its value in early diagnosis and breed control. Although the RCD3 form of PRA has not been previously reported in Collies or Australian Shepherds, it was included in our analysis due to the genetic relatedness among herding breeds and the potential presence of undetected carriers resulting from historical crossbreeding.

Hereditary diseases represent a serious problem in horses, especially in terms of sport use and breeding. Nowadays, we know the genetic basis of several breed-specific inherited diseases. In this study, we focused on the cytogenetic analysis of the clinical case of a healthy mare and her foal with numerous malformations in order to confirm or disprove the suspicion of genetic causes of a disability in this offspring. We used conventional metaphase staining to analyse chromosomal aberrations – breaks and gaps. In general, the number of breaks exceeding the norm (2—3 breaks/100 meta-phases) may indicate the influence of the external environment with a potential teratogenic effect on the offspring during its mother gravidity. Compared to the norm, we found a slightly increased percentage of chromosomal aberrations in both the mother and the foal. As another method, we used karyotyping to assess the number and morphology of chromosomes, where in addition to conventional staining, we also applied differential staining of metaphases (G-banding). Multiplication, loss or rearrangement of chromosome segments are almost always associated with pathology. In the karyotypes we constructed, we observed changes in both individuals, compared to the international standard; in the mare, we probably recorded the mosaic form of her karyotype. In the foal, we found 64, XX with a suspected morphological change which was probably related to autosomal chromosome pair 31. The cytogenetic analysis of suspected individuals is also very beneficial for horse owners and breeders. Thanks to the combination of cytogenetic and modern molecular-genetic methods, we were able to identify individuals unsuitable for breeding.