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Open access

I. Paulíková, H. Seidel, O. Nagy, Cs. Tóthová, J. Konvičná, M. Kadaši and G. Kováč

Abstract

This study investigated the changes in: thyroid hormones, amount of subcutaneous fat, and selected indices of blood biochemistry in dairy cows in relation to the reproduction/production cycle. The blood samples were collected both ante- and post-partum every two weeks. When evaluating the mean values of the investigated indices, the major changes were recorded in dairy cows 3 to 14 days after calving. During this period, we observed a significant decrease in the mean serum levels of T3 (P < 0.05), T4 (P < 0.01), and triglycerides (P < 0.01). An opposite trend was observed with a significant increase after calving in the: mean serum levels of β-hydroxybutyrate (P < 0.05), urea (P < 0.01), and mean AST activities (P < 0.05). A significant increase over the normal range was recorded in the average levels of non-esterified fatty acids (P < 0.01) and total bilirubin (P < 0.01). From the next sampling (28 days after calving) onwards we recorded a significant increase in the blood serum levels of cholesterol (P < 0.01), total lipids (P < 0.01), total protein (P < 0.01), as well as a significant decrease in the insulin levels (P < 0.05) and a reduced layer of subcutaneous fat (P < 0.01). The blood serum iodine concentration showed only slight significant changes (P < 0.05) during the observation. Blood serum levels of glucose did not show any significant changes during the whole observation period. Within the whole observation period we found a negative correlation between T3 levels and the layer of subcutaneous fat (r = −0.2606; P < 0.05). This correlation was much more marked in cows 3 to 14 days after calving (r = −0.5077; P < 0.05), which may indicate a possible relationships between the thyroid status, body condition, and post partum negative energy balance.

Open access

K. Englerová, R. Nemcová and D. Mudroňová

Abstract

The aim of this study was to identify beneficial bacteria with probiotic potential from kefir grains. The lactobacilli isolated from kefir grains were characterised as: Lactobacillus plantarum, Lactobacillus paraplantarum, Lactobacillus paracasei, and Lactobacillus kefiri. The strains Lb. plantarum 1Ž, Lb. paraplantarum S10, and Lb. paracasei 2Ž tolerated better the test gastric juice at pH 2 and 2.6 during 120 min of incubation in comparison with the strains Lb. kefiri. On the other hand, the strains Lb. kefiri were resistant to 0.3 % bile acid salts. The Lb. paracasei 2Ž showed the significantly highest survival (P < 0.001) at pH 2 in comparison with all other strains tested and was also able to tolerate 0.3 % concentration of the bile salts. All strains produced medium to strong biofilms on abiotic surfaces and inhibited the growth of selected potential pathogens with varying intensity. All kefir isolates were susceptible to the antibiotics tested and exhibited positive β-galactosidase activity with the exception of Lb. paracasei 2Ž which did not show any activity of undesirable enzymes, such as β-glucosidase and β-glucuronidase. Additional testing and validation of the biological properties and safety of the strain Lb. paracasei 2Ž under in vivo conditions are needed to confirm the prospective use of this strain in practice.

Open access

I. M. Kovalyova, O. P. Melnyk, L. Kresakova and K. Vdoviakova

Abstract

Despite the obvious existence of guttural pouches in Equidae, the question of their function has not yet been adequately answered. We suggest a working hypothesis that the guttural pouches of horses may be an additional organ of gas exchange. Research on the topographical location of the guttural pouches of horses and on the micro-morphological structures of their walls were carried out. It appears possible that: the dense arrangement of the vascular system of the wall of the guttural pouches near the main cerebral vessels; the constant moistening of the inner surface of the wall of the guttural pouches; and the air circulation in it; strongly suggests that the guttural pouches of horses may serve as an additional organ of gas exchange. The guttural pouches becomes very useful, particularly during prolonged periods of intense physical activity.

Open access

Z. Sihelská, M. Pangrácová Piterová, E. Čonková, M. Harčárová and E. Böhmová

Abstract

The genera Malassezia and Candida include yeasts which are members of the normal mycobiota of the skin and mucosal sites of humans and other warm-blooded animals. These yeasts are associated with a variety of dermatological disorders and also systemic diseases in humans and other animals. This study confirms the occurrence of Malassezia and Candida species in healthy dogs. Samples were collected from different body sites: external ear canal, interdigital area, skin of the axilla and of the neck, and the oral and rectal mucosae. The isolates were identified using phenotypic methods (biochemical-physiological and morphological characteristics). The presence of yeasts were investigated in the specimens from 70 healthy dogs. Malassezia species were isolated in 44 dogs from which 84 Malassezia isolates were obtained. Only one Candida isolate was obtained from the dogs examined. It was found that Candida does not occur in dogs normally and Malassezia was the main colonizing yeast in healthy dogs.

Open access

A. I. Adebiyi and A. F. Fagbohun

Abstract

Infectious bronchitis (IB) is an acute infectious viral disease causing severe economic losses in poultry production. In Nigeria, there has only been monitoring of the disease in chickens with little attention given to other bird species. For this study, blood samples were collected from 184 apparently healthy, unvaccinated birds which comprised of 61 captured free-living pigeons, 60 free range indigenous chickens and 63 intensively reared Japanese quails. Sera from these birds were screened for IB virus antibodies (IBV) using a commercial ELISA kit. The birds were from Oyo and Osun States, in southwest Nigeria. Overall, 63 (34.2 %) sera were positive for IBV with 3.3 % (2/61), 95.0 % (57/60) and 6.3 % (4/63) from pigeons, indigenous chickens and Japanese quails, respectively. These findings suggest that they were subclinically infected with either field or vaccine virus and could thus serve as possible reservoirs of this virus to domestic poultry. Thus, there is need for continuous surveillance of the disease in different bird species and their possible role in the spread of IBV in Nigeria.

Open access

E. Marettová

Abstract

The elastic fibres are particularly important for the structural integrity and function of the prostate. In this study, the elastic fibres of the normal dog prostate gland were identified by immunohistochemistry. In the capsule, the elastic fibres form membranes of different thicknesses-located mainly in the intermediate and deep zones. Large trabeculae which extend from the capsule contain elastic fibres with a prevalence in the longitudinal direction. Around blood vessels, the elastic fibres are concentrated and form annular structures. In the fine septa supporting the lobules, elastic fibres form a fine elastic meshwork. Between the secretory units of the prostate gland, the fine elastic fibres are located under the secretory epithelium. An increase of elastic fibres around the ducts entering the urethra was observed. An accumulation of elastic fibres in the capsule and stromal septa may participate in the releasing of secretory products during ejaculation.

Open access

L. Hamilton and M. Kožár

Abstract

Skin wounds are a common presentation in small animal practice. These wounds may be acute or chronic with a complicated healing process. An important aspect of the healing of wounds is debridement which may be carried out by surgical, autolytic, mechanical or enzymatic methods. The debridement method is chosen according to the individual skin defect and influenced by factors such as wound size and location, the age of the wound, and the presence of infection or exudate. Enzymatic debridement is a method that is not commonly used in veterinary practice, and involves the use of enzyme preparations to remove necrotic tissue from a wound. The aim of this study was to investigate the effects of the enzymatic ointment collagenase as a method of debridement, and its effect on the macroscopic appearance of chronic skin wounds in cats and dogs. We observed that the application of Iruxol Mono directly to the wound changes the progress of the healing process, with no obvious adverse effects. The time of healing of chronic wounds was decreased and healthy granulation tissue was developed within a couple of days after application of the ointment. Enzymatic debridement appears to be a promising method of debridement for use in chronic wounds, and should be considered in cases where more conventional methods of debridement are ineffective or unsuitable.

Open access

Z. Kubicová, M. Filipová, J. Jurovčíková and L Cabanová

Abstract

The molecular typing of Listeria monocytogenes isolates is an important tool for monitoring the spread of the strains in food chains, providing evidence for epidemiological investigations and for the detection of out-breaks. The demand of European typing data centralization, collection and sharing stimulated the generation of “EURL L. monocytogenes Database (EURL Lm DB)” in 2012 led by the European Union Reference Laboratory (EURL) for L. monocytogenes (ANSES Maisons-Alfort Laboratory for Food Safety, France) in close collaboration with Applied Maths. This database includes the typing results and epidemiological information on strains isolated from food, environmental or animal samples and it is in connection with human strains database TESSy (The European Surveillance System) led by the ECDC (European Centre for Disease Prevention and Control). In total 147 L. monocytogenes isolates were examined by PFGE (pulsed field gel electrophoresis) in 2014—2015 in VFI Dolny Kubin from different sources. Nearly half (68) of the 147 isolates in the national Slovak database came from milk or dairy products samples and the related manufacturing environment. In this work, 68 isolates associated with milk were selected and divided into 27 clusters (95 % similarity level) after combined comparison analysis (AscI and ApaI) by BioNumerics 6.6 software. Eight clusters included three or more similar PFGE profiles.

Open access

G. Daniel-Igwe and N. Okwara

Abstract

One hundred (50 males and 50 females) B-not strain indigenous turkeys, Meleagris gallopavo, were used to determine the reference values for their haematological parameters. The turkeys were housed in the poultry unit and jugular venepunctures were used to collect their blood. The haematological parameters were determined using standard procedures. The mean values of: the packed cell volume (PCV; 37.29 ± 0.37 %), red blood cell (RBC) counts (2.50 ± 0.44 × 106.µl−1), haemoglobin concentration (Hbc; 10.89 ± 0.34 g.dl−1), mean corpuscular volume (MCV; 150.63 ± 0.73 fl), mean corpuscular haemoglobin (MCH; 44.29 ± 1.78 pg), mean corpuscular haemoglobin concentration (MCHC; 29.10 ± 0.73 g.dl−1), and white blood cell (WBC) counts (12.41 ± 0.83 × 103 µl−1) were determined. No significant differences were found between the male and female B-not strain turkeys in this study. The results will help in the interpretation of cases of disease when there are variations in the values and serve as baseline data for B-not strain of turkeys in the humid tropics.

Open access

I. Šulla, V. Balik and M. Šarišský

Abstract

This study was initiated in order to test a mini-invasive method of mesenchymal stem/progenitor cells (MS/PCs) isolation from a rat bone marrow (BM), and subsequently their expansion, differentiation, and evaluation of their immunophenotypic characteristics; and later their preservation as donor cells in an optimal condition for potential autotransplantation. The study group comprised of 6 adult male Sprague-Dawley (S-D) rats, weighing 480—690 g. The rats were anaesthetised by isoflurane with room air in a Plexiglas box and maintained by inhalation of a mixture of isoflurane and O2. Their femurs were surgically exposed and their diaphyses double-trephined. Then BM cells were flushed out by saline with heparin and aspirated into a syringe with a solution of DMEM (Dulbecco’s modified eagle’s medium) and heparin. The mononuclear cells from the BM were isolated by centrifugation and expanded in a standard culture medium supplemented with ES-FBS (es-cell-qualified foetal bovine serum), L-glutamine and rh LIF (recombinant human leukemia inhibitory factor). Following 14 days of passaging cultures, the cells were split into 2 equal parts. The first culture continued with the original medium. The second culture received additional supplementation with a human FGFβ (fibroblast growth factor beta) and EGF (epidermal growth factor). The populations of these cells were analysed by light-microscopy, then the mean fluorescence intensities (MFIs) of CD90 and Nestin were evaluated by a tricolour flow cytometry using monoclonal antibodies. The type of general anaesthesia used proved to be appropriate for the surgical phase of the experiments. All rats survived the harvesting of the BM without complications. The total number of mononuclear cells was 1.5—4.0 × 106 per sample and the proportion of CD90/Nestin expressing cells was < 1 %. Following 14 days of expansion, the cells became larger, adherent, with fibrillary morphology; the proportion of cells expressing CD90/Nestin increased to almost 25 %, i. e. they earned basic phenotypic characteristics of MSCs. Throughout the further cultivation a gradual decrease of the CD90/Nestin expression occurred. This suggested that the suitability of rat bone marrow derived MS/PCs for replacement therapy would probably be the highest between days 12—15 of cultivation and then would diminish.