The aim of this study was to assess the impact of asymptomatic infections of mink with Aleutian mink disease virus (AMD on reproductive performance and the morphology of the internal organs. The study drew its subjects from two farms where the disease was endemic and included 450 clinically healthy female mink divided into three equal groups: two AMD positive groups and one AMD negative control group. The mink were subjected to clinical observations throughout the period of reproduction, and then for the first seven weeks after birth. Data collected during this period were evaluated using selected breeding and reproductive indices. All reproductive indices including conception rate, litter size, and litter weight at birth as well as neonatal mortality were substantially poorer. Histopathological examination revealed changes typical for AMD, particularly in the spleen, kidneys, liver, and lymph nodes. The results highlighted and proved the frequently underestimated extent of economic losses on farms where AMD is endemic yet the mink stock is apparently healthy.
The aim of this study was to characterise the genetic variability of the Aleutian mink disease virus (AMDV) circulating among mink farmed in Poland and to compare Polish isolates with AMDV variants available in the GenBank database. For this purpose PCR amplification and analysis of the 429 bp DNA fragment of the AMDV NS1 gene from 13 randomly selected AMDV infected mink was performed. A comparison showed that all tested amplicons were closely related to the sequence of the NS1 gene of AMDV and showed high (94%-97%) homology to virus variants from American mink (Neovison vison) isolated in Canada in 2007-2008. Eleven samples showing a high percentage (95%-97%) of sequence similarity together with three similar isolates originating from Canada formed one clade (monophyletic group). Two variants showing a lower percentage (about 94%- 95%) of sequence similarity to isolates from Canada formed a separate clade. Polish viruses can be subdivided into two main groups with a putative ancestor common to both Polish and three Canadian isolates. This result confirms the literature data indicating the occurrence of American mink in Eastern Europe (including Poland) from the 1950s when the animals were imported for breeding purposes. In conclusion, we provide for the first time a report on the genetic characteristics of the AMDV variants circulating in the Polish population of farmed mink and their relationship with previously known AMDV variants isolated and described abroad.
The aim of this article was to evaluate the influence and effects of chosen bioaccumulative substances i.e. heavy metals, pesticides, and polychlorinated biphenyls (PCBs) on fish, as well as provide information on time trends and potential threat to human health. Chemical substances which pollute water may affect living organisms in two ways. First of all, large amounts of chemical substances may cause sudden death of a significant part of the population of farmed fish, without symptoms (i.e. during breakdown of factories or industrial sewage leaks). However, more frequently, chemical substances accumulate in tissues of living organisms affecting them chronically. Heavy metals, pesticides, and polychlorinated biphenyls are persistent substances with a long-lasting biodegradation process. In a water environment they usually accumulate in sediments, which makes them resistant to biodegradation processes induced by, e.g., the UV light. These substances enter the fish through direct consumption of contaminated water or by contact with skin and gills. Symptoms of intoxication with heavy metals, pesticides, and PCBs may vary and depend on the concentration and bioavailability of these substances, physicochemical parameters of water, and the fish itself.
The aim of this study was to assess the effect of thymus factor X (TFX-Jelfa) treatment in hypoestrogenic female rats for the purpose of decreasing skin impairments. Ovariectomised rats were used as a model. The histopathological analysis of the skin after TFX-Jelfa treatment demonstrated that the epidermis was thicker and more desquamated, without deep wrinkles or hypersecretion in comparison to the skin of animals only castrated and not treated with TFX-Jelfa. Collagen and elastic fibres were arranged more uniformly in the dermis and there were numerous fibroblasts, hair follicles, and small vessels. Ultrastructural analysis showed keratinocytes without degenerative changes and the proliferation of lymphatic and dendritic cells in the skin. The results indicate that thymus extracts can have beneficial effects on skin aging, which is often accompanied by hormonal perturbances.
Koi herpesvirus (KHV) has infected farmed common carp in Poland clinically and asymptomatically since 2004. The role of non-carp species as vectors of virus transmission is well known except for in the case of KHV. The aim was to better understand this virus’ infection and transmission pathways in common carp, looking at the potential vector role of fishes kept with them.
Material and Methods
Eight species were experimentally infected with KHV by immersion in a suspension at 20°C ±1 and transferred to a tank after 45 minutes. Specimens were euthanised at intervals up to 56 days post infection (dpi) and tissue was examined for KHV DNA. Surviving infected fishes were introduced at intervals, each time into a separate tank, to naïve common carp for experimental infection. These were observed daily for symptoms, sacrificed along with controls after three months, and dissected to provide tissue samples. Also fish from 14 species collected from a farm with a history of KHV were sampled from 3 to 22 months after disease was confirmed. Organ sections from single fish were collected in a single tube.
Viral DNA was detected in tench and roach samples up to 49 dpi, but in three-spined stickleback and stone maroko samples only up to 14 dpi. Transmission of KHV to naïve carp occurred after cohabitation. KHV DNA was detected in three fish species three months after the farm outbreak.
We confirmed that grass and Prussian carp, tench, roach, and brown bullhead can transfer the virus to naïve common carp.
The aim of the study was to identify the genotype of Polish isolates of salmonid alphaviruses (SAV) and to find the origin of the virus. Samples for virus isolation included the kidneys, spleen, and liver pooled from 10 fish. A typical cytopathic effect was observed after inoculation of samples on cell lines. Total RNA was extracted from cell culture supernatant and submitted to RT-PCR with primers amplifying two informative regions of the genome: a conserved region in the E2 gene and a variable region in the nsP3 gene. The sequences revealed that the strain from Poland belonged to subtype SAV 2, indicating a very strong genetic identity with isolates from Italy and France.
The aim of the study was to assess the changes of blood parameters in 12 three-week-old Polish Merino sheep subjected to experimental jaagsiekte sheep retrovirus (JSRV) infection.
Material and Methods: Haematological (WBC with leukocyte subpopulations: GRA, LYM, MID, and RBC, MCV, MCH, MCHC, HGB, HCT, PLT, and MPV) and biochemical blood parameters (acid/base balance, cation/anion content, and gasometry) were determined in blood samples collected one month after JSRV infection, then at four-week intervals for five consecutive months.
Results: A decrease in RBC, HCT, MCV, PLT, MPV, and LYM values in comparison with controls was found in the last month of observation. On the other hand, at the same time, an increase in HGB, MCH, MCHC, WBC, MID, and GRA indices was observed. Moreover, at the end of experiment blood gasometric indices such as pCO2, HCO3, and tCO2, and Na and K ion concentrations were higher in the affected lambs than in the healthy animals. The pH values of the challenged animals exhibited less alkaline character than in the case of controls, which was associated with a decrease in O2% saturation. However, the majority of differences between JSRV inoculated and control groups was not statistically significant.
Conclusion: The observed changes in the examined blood parameters can be considered as prodromal symptoms in the preclinical phase of adenocarcinoma development associated with JSRV infection.
The outbreak of chlamydiosis in one of the western provinces of Poland, was diagnosed accidentally as a concurrent infection in a commercial laying hen flock during an outbreak of fowl pox. For histological examination, skin and subcutaneous tissue samples from lesions on heads of the birds were collected. Swabs from throat and trachea have been examined by nested PCR, real-time PCR, and partial ompA sequencing. Detailed electron microscopy analysis revealed fowl pox intracytoplasmic inclusions, called Bollinger bodies, and the presence of other intracytoplasmic inclusions; specific for Chlamydia sp. Results of nested PCR confirmed the presence of Chlamydiaceae sp. in two tested samples. Surprisingly, one of the two Chlamydiaceae-positive cases turned out to be infected with a non-classified strain. Results of real-time PCR and sequencing confirmed the presence of a new Chlamydia species that has not been found in Poland to date. Partial sequencing and BLAST analysis of ompA gene sequence confirmed the highest homology to non-classified poultry strains of Chlamydia sp. that were previously detected in Germany and France. The zoonotic potential and the exact taxonomic status of this atypical strain have yet to be defined.
Histopathological examination of liver, kidney, spleen, pancreas, duodenum, jejunum, skeletal muscle, and bursa of Fabricius samples, collected from broiler chickens, laying hens, fattening pigs, and calves fed genetically modified corn MON 810 and soybean meal MON-40-3-2 (Roundup Ready, RR), was performed The examination showed no significant differences between the control animals fed diets containing no genetically modified feeds and animals fed genetically modified feeds. In some cases, congestion of parenchyma and focal lymphoid cell infiltrations were observed in all dietary groups, including controls, and therefore, it was assumed that the lesions were not associated with the feeding transgenic feeds.
Introduction: The influence of feeding genetically modified MON 810 hybrid maize on the growth and haematological and biochemical indices of rats was tested.
Material and Methods: Two conventional (non-GM) and two test (MON 810) lines of maize were used in semi-purified diets at the level of 40% w/w. The non-GM I, MON 810 I, non-GM II, and MON 810 II maize lines were near-isogenic. A total of 40 male 6-week-old Wistar-derived rats were assigned to four equal feeding groups corresponding to the four maize lines for 16 weeks. Overall, health, body weight gain, clinical pathology parameters, gross changes, and appearance of tissues were compared between groups.
Results: There were no statistically significant differences in the weight gain or relative organ weights of rats, but there were some non diet-related histopathological changes in the liver, kidneys, and spleen. Except for creatinine level, no diet-related effects were observed in haematology or most of the biochemical indices. Transgenic DNA of MON 810 maize was not detected in the tissues or faeces nor in the DNA of E. coli isolated from the rectum digesta of rats given transgenic feeds. In our experiment, various metabolic indices of rats fed non-GM diets or genetically modified (MON 810) maize for 16 weeks were similar. No adverse nutrition-related health effects were detected.
Conclusion: MON 810 maize seems to be as safe as the conventional maize lines.