Spitting cobras: Experimental assay employing the model of chicken embryo and the chick chorioallantoic membrane for imaging and evaluation of effects of venom from African and Asian species (Naja ashei, Naja nigricollis, Naja siamensis, Naja sumatrana).

Among the captivating world of venomous snakes, an outstanding group of cobras from the family Elapidae is characterized by a distinctive structure of proteroglyphous venom apparatus that allows the ejection of venom from the fangs and formation of aerosol particles. The venom of "spitting" cobras is innocuous when sprayed over the intact skin, but contact with the eye surface is followed by ophthalmia and a temporary blindness, that may remain permanent, unless immediate and adequate medical interventions are carried out. The aim of this work was to monitor and evaluate induced vasoactive effects as well as embryotoxic effects with the regard to the whole crude venom of four "spitting" cobra species (African species Naja ashei and Naja nigricollis, Asian species Naja siamensis and Naja sumatrana). Vasoactive effects were visualized using the Hen's Egg Test - Chorioallantoic membrane (HET-CAM) test. The Chick Embryotoxicity Screening Test (CHEST) was used to estimate embryotoxicity and the data were then processed using statistical analysis. The highest embryonic mortality rate was observed after administration of venom from Naja nigricollis among the whole crude venoms tested. All tested venoms induced fast spreading of pathological alterations in the blood vessels on the chorioallantoic membrane. Our study discloses a detailed insight into microscopic level processes in venom-induced changes observed on the chicken embryos and on the vascular network in their chorioallantoic membrane. This article also highlights the increasing importance of the role of the chicken embryos and the importance of observing changes in the chorioallantoic membrane applied for toxicological and medical research as an appropriate alternative animal model in relation to 3R's principles.

Evaluation of vasoactivity after haemotoxic snake venom administration.

The chick chorioallantoic membrane (CAM) is a widely used model in medical research and fulfils the requirements laid out in the 3 R's. The CAM, contains a dense network of blood vessels, essential for embryo development but also makes the chick embryo an invaluable resource for the study of angiogenesis and the haemotoxicity of substances. Non-neurotoxic snake venom is responsible worldwide for numerous deaths but also has been found to have a vast range of medicinal benefit. This study combines evaluating the time of onset and intensity of effects of three whole viper venoms (Bitis aritans, Crotalus viridis, Agkistrodon contortrix) at varying concentrations. They were applied onto the CAM, using the Luepke grading system as one method of determining their rapid irritation potential. Regarding the principles of 3 R's, this method helps to evaluate the haemotoxic effect of venom as an alternative method to the rodent tests. The information provided from these results can be used as a rapid tool for both medical management of snakebite wounds and the potential use of snake venom in medical treatments. Then, Luepke grading system can help to evaluate the haemotoxic effect of venom in combination with other appropriate methods.

DNA detection of Toxoplasma gondii in sheep milk and blood samples in relation to phase of infection.

Toxoplasma gondii is a worldwide parasite that is important both for veterinary medicine (economic losses in the herd) and for public health (immunocompromised patients and pregnant women). An important source of Toxoplasma infection in humans is consumption of contaminated meat and milk (undercooked meat and unpasteurized milk). Small ruminants are important in both milk and meat production throughout the world because of free-range husbandry. The purpose of our study was to detect the presence of T. gondii DNA in ewes' milk 1 month after the term, and to determine the relationship between the occurrence of this DNA in blood and milk based on the phase of infection. Using enzyme-linked immunosorbent assay (ELISA) the animals were divided into two groups (immunoglobulin M positive (IgM+), IgM-). With real-time polymerase chain reaction (PCR), T. gondii DNA was detected in seven milk samples (28%) and five blood samples (20%) of the IgM+ group (25 samples). In the IgM- group T. gondii DNA was detected in two milk samples (3.6%) out of 55 samples.

Arterial peculiarities of the thoracolumbar spinal cord in rabbit.

The aim of this study was to investigate the arterial blood supply of the thoracolumbar spinal cord in rabbit. The study was carried out on twenty adult New Zealand white rabbits. Ten rabbits were used in the corrosion technique and ten rabbits in the dissection technique. After the killing, the vascular network was perfused with saline. Batson's corrosion casting kit no. 17 © was used as a casting medium. After polymerisation of the medium, in ten rabbits the maceration was carried out in KOH solution, and in ten other rabbits, formaldehyde was injected by the dissection technique into the vertebral canal. We found high variability of segmental arteries supplying blood to the spinal cord. There are 12 intercostal arteries and 1 costo-abdominal artery. Dorsal branches arising from the dorsal surface of the aorta thoracica were found as follows: in 70% of the cases, 9 pairs were present; in 20% of the cases 8 pairs; and in 10% of the cases 10 pairs. The paired arteriae lumbales were present in 6 pairs in 90% of the cases and in 5 pairs in 10% of the cases. On the dorsal surface of spinal cord, we found two irregular longitudinal arteries in 70% of the cases, no longitudinal arteries in 20% of the cases and three irregular longitudinal arteries in 10% of the cases receiving dorsal branches of rami spinales. Among the dorsal branches observed in the thoracic region, 60.5% were left-sided, 39.5% right-sided and in the lumbar region, 52.5% were left-sided and 47.5% right-sided.

The occurrence of microsporidial infections and toxoplasmosis in Slovak women.

AIM OF THE STUDY: To determine the prevalence of antibodies to intracellular pathogens (Toxoplasma gondii, Encephalitozoon cuniculi, and Encephalitozoon intestinalis) in sera of Slovak women. MATERIAL AND METHODS: Enzyme-linked immunosorbent assay (ELISA) was used for the detection of specific IgG antibodies to Toxoplasma gondii, Encephalitozoon cuniculi, and Encephalitozoon intestinalis in 118 sera samples from Slovak women with different diagnoses. RESULTS: Women were divided into three groups based on the age. In group 1 (n = 26, age > 51), nine women tested positive for T. gondii, two for E. cuniculi, and one for E. intestinalis. The respective numbers in group 2 (n = 53, age range 36-50) were 18, three, and seven, and in group 3 (n = 39, age range 20-35) 13, two, and four. In an attempt to find the relationship between the clinical diagnosis and the prevalence of the three pathogens, we divided the study subjects into four groups based on the condition (diseases of the nervous, respiratory, and immune systems and pregnancy). A statistically significant relationship between the diagnosis and the prevalence of a pathogen was found (p < 0.001). In women with diseases of the respiratory system, antibodies against Toxoplasma gondii were most often detected, while infection with E. intestinalis was most commonly associated with nervous system diseases and the highest seroprevalence of E. cuniculi was found in women diagnosed with immune system disorders. CONCLUSIONS: In our study, the seroprevalence rates of the three infections in pregnant women were similar, showing no significant difference. Women with diseases of the respiratory system were most often seropositive for T. gondii. Our result is consistent with the known fact that in humans, toxoplasmosis may affect various organs of the body, causing diverse clinical signs. However, the respiratory system is commonly involved and pneumonia may result. The most common finding is a mild, flu-like illness that lasts a few days. The women with different types of immunodeficiency disorders had the highest seropositivity rates for E. cuniculi and the second most common infection in this group was toxoplasmosis. Both of these parasites are opportunistic and can cause serious problems in immunocompromised individuals (HIV-positives, organ transplant recipients, chemotherapy patients). The women diagnosed with the nervous system disorders were most commonly infected with E. intestinalis. The relationship between the disease and this pathogen is not clear, but E. intestinalis is responsible for various pathologies; it causes mainly disseminated infections and damage to the digestive tract. E. intestinalis is a parasite very close to E. cuniculi affecting either the nervous system or the respiratory tract depending on the type of host.

Anatomical study of blood supply to the spinal cord in the rabbit.

STUDY DESIGN: The study was carried out in rabbit. OBJECTIVE: To investigate the arterial blood supply of the spinal cord in rabbit as model in experimental spinal cord ischemia surgery. SETTING: The study was carried out in the Department of Anatomy, Histology and Physiology, University of Veterinary Medicine and Pharmacy in Kosice, Slovak Republic. METHODS: The study was carried out on 10 adult New Zealand white rabbits. We prepared corrosion casts of arterial system of spinal cord. Batson's corrosion casting kit no. 17 was used as a casting medium. RESULTS: The presence of branches entering arteria spinalis ventralis in the thoracic region was observed in 71% of the cases on the left side and in 29% on the right side. In the lumbar region, left-sided branches were observed in 52% of the cases and right-sided in 48% of the cases. The artery of Adamkiewicz was present in 50% of the cases as left-sided and in 50% as right-sided. CONCLUSION: Documenting the anatomical variations in spinal cord blood supply in the rabbit will aid in the planning of future experimental studies and determining the clinical relevance on such studies.

Encephalitozoonosis in household pet Nederland Dwarf rabbits (Oryctolagus cuniculus).

The paper presents the results of examination of 32 domestically bred rabbits, the breed Nederland Dwarf of Oryctolagus cuniculus, for the presence of Encephalitozoon cuniculi microsporidian species. The results of serological tests for E. cuniculi in 32 rabbits are reviewed along with other follow-up studies of clinical cases. Blood samples were taken from 7 asymptomatic rabbits and 25 rabbits showing neurological and ocular signs suggestive of encephalitozoonosis. In the asymptomatic group, 5 out of 7 rabbits were seropositive (71%). 16 rabbits with clinical diseases showed neurological sings, including torticollis, circus-like movements, loss of weight; 6 of them also showed ataxia, anorexia, asthenia of hind-limbs and 3 showed ocular signs. All 25 rabbits were seropositive. The spores of E. cuniculi were isolated from the faecal samples or kidneys and brain of an animal and subsequently were used for DNA isolation and PCR analysis.