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Development of EST microsatellite markers for the Tasmanian palaeoendemic conifer Lagarostrobos franklinii (Hook. f.) Quinn (Podocarpaceae)

Abstract

Nuclear Expressed Sequence Tag (EST) microsatellite markers were developed for the Tasmanian palaeoendemic conifer Lagarostrobos franklinii (Hook.-f.) Quinn for genetic studies. RNAseq data was mined for EST microsatellites, and primer pairs were synthesised from 70 contigs with 50 producing amplification products. Of these 50, 10 reliably amplified and displayed polymorphism across 8 samples representing the entire species range. The genetic diversity of these 10 loci was then examined in three wild populations (84 samples). The number of alleles varied from two to thirteen per locus with the average number of alleles per population ranging between 3.0 – 4.7. Observed and expected heterozygosity ranged from 0.34 – 0.42 and 0.37 – 0.44, respectively. Marker cross-amplification was tested in the New Zealand sister species Manoao colensoi (Hook. f.) Molloy, but no markers amplified reliably, which possibly reflects the age of divergence between these species (~64 million years). These are the first microsatellite markers developed for the monotypic genus Lagarostrobos. They will be valuable for assessing the species extant genetic diversity, the impact of past climatic perturbations and human disturbance and the role of clonal propagation in recruitment.

Open access
Genetic control of coppice regrowth in Eucalyptus spp.

Abstract

Forest companies prefer a coppice system as a silvicultural strategy owing to its economic and sustainability advantages compared to developing new plantations for second rotations. However, studies aiming to determine the selection of superior genetic material for this management strategy are scarce. In this study, we evaluated five clonal tests of Eucalyptus spp. located in Itatinga and Angatuba, São Paulo State, Brazil, to determine the genetic correlations and control of productivity for regrowth management in two rotations. The volume (m3) and survival of the Eucalyptus spp. clonal tests were determined for the two rotations at 5.5 years of age. The experiments were carried out in a randomized block design with six replicates, five plants per plot, and unbalanced treatments. The heritability in the normal scale (h^n2) for the survival ranged from 0.056 to 0.11, the heritability in the broad sense (h^g2) ranged from 0.205 to 0.334, and the genotypic correlation was positive and high (0.71-0.86), and statistically significant to the genetic means for the two rotations. The ranking of the best clones in the second rotation was similar (76 %) to their ranking in the first selection. Thus, for the evaluated material, there was no need for the second measurement to obtain accurate selection when managing a coppice system.

Open access
Antioxidant Enzymes of Honeybee Larvae Exposed to Oxamyl

Abstract

Oxamyl is a carbamate insecticide used to control a broad spectrum of insects. It can also affect non-targeted organisms when applied incorrectly. The world food production depends partially on honeybee pollination abilities and therefore it is directly linked to the health of bees. The success of the colony development depends, among other factors, on the health of the larvae. The first 6 days are crucial for their development. In this stage, the worker larvae grow exponentially and may be exposed to xenobiotics via their diet. In this study, we investigated the effect of oxamyl on honeybee larvae (Apis mellifera) by monitoring the changes in their antioxidant enzyme system. The activities of superoxide dismutase, catalase and glutathione-S-transferase were determined in the homogenates of in vitro reared honeybee larvae after their single dietary exposure to oxamyl at doses of 1.25, 2.5, 5, 10 and 20 µg a.i./larva (a. i.—active ingredient). The doses of oxamyl did not cause statistically significant changes in the activities of the enzymes. Even a slight activation of these enzymes protected the larvae from the adverse effects of the reactive oxygen species (ROS). Marked changes in both the enzyme activity and the content of lipid peroxidation products were observed at the oxamyl dose of 10 µg a. i./larva. This fact may indicate a potential oxidative damage to the larvae. These results allowed us to assume that the toxic effects of oxamyl involves not only the inhibition of acetylcholine esterase but is also associated with ROS production.

Open access
Combination of Beta Glucan, Honey and Chlorhexidine in the Wound Management in a Cat a Case Report

Abstract

Wound management is one of the oldest and one of the most frequent therapeutic activities in medicine. Over the centuries there has been described and tested many therapeutic substances for the treatment of wounds with various effects. Due to the discovery of antibiotics, a wound management regime used to be limited only to a local application. Over years, it has been shown, that comprehensive therapy which uses only antibacterial preparations, also may contain some negative points (resistance of aggressive pathogens, toxicity, allergic reactions, etc.). According to studies, the best solution to this problem is a local application, using preparations that ensure the sterility of the affected parts of the skin, and the utilization of agents that are able to accelerate the granulation and lead to the healing process of the wound. Products that contain beta glucan combined with a gentle but effective antiseptics (chlorhexidine digluconate), or natural substance with antiseptic and also nourishment effect (honey), are very beneficial in wound management. A good penetration of active agents, the ability to moisturize defective tissues, and to make a protective film that hinder the intersection of impurities and decrease secondary contamination, are the benefits of a gel formulation, that is the most appropriate external form of application in veterinary practice that can improve and accelerate a successful healing process of wounds in animals.

Open access
Detection of Chromosomal Breaks Induced by Thiacloprid in Human Lypmhocytes and Detection of Double-Strand Breaks Based on γH2AX Histone Phosphorylation

Abstract

Thiacloprid, a neonicotinoid insecticide, is widely used to control various species of pests in the current agriculture of today. The potential genotoxic effects of thiacloprid on human peripheral blood lymphocytes were investigated in vitro by chromosome aberrations (CA), and double-strand breaks (DSB), which were detected by the phosphorylation of γH2AX histone. Human peripheral blood lymphocytes were exposed to 30, 60, 120, 240, 480 µg.ml−1 doses for the last 24 and 48 hours of culture. Thiacloprid increased CA at the concentrations of 240, 480 μg.ml−1 (P < 0.05), but these results did not confirm genotoxicity. The mitotic index (MI) was important to us; it served as a basis for the confirmation of the cytotoxicity of this insecticide. During 48 hours of culture, at the concentration of 480 µg.ml−1, its value rapidly decreased (0.42) (P < 0.001), which did not allow us to analyse the results because of the high cytotoxic response.

Open access
Histological Scoring Systems in the Cartilage Repair of Sheep

Abstract

Researchers around the world use histological analysis to provide the most detailed morphological information of articular cartilage repair and it predominantly relies on the use of histological scoring systems which are important tools for valid evaluations. Due to hyaline cartilage complex structure and avascular nature, damaged cartilage does not heal spontaneously and it is still a challenge to regenerate and restore its tissue function. The aim of this study was to investigate the quality of regenerated cartilage by using three different histological scoring systems; O’Driscoll, Pineda and Wakitani which are all classic scores described for such animal studies. We used an in vivo ovine model in which a full thickness chondral defect was created and then implanted with the biomaterial (polyhydroxybutyrate/chitosan; PHB/ CHIT). The results of this histological analysis demonstrated that the cartilage repaired tissues received scores indicating that the majority of the regenerated tissue resembled hyaline-like cartilage. After six months of repair the regenerated cartilage showed characteristics like good surface continuity, uniformed stained extracellular matrix, clearly visible zones and cellular proliferation. In conclusion, this study may be used to investigate and improve the regenerative capacity of hyaline cartilage in preclinical models and it also sheds further light on both the evaluation and methods used for the regeneration of damaged cartilage.

Open access
Observation of Seasonal Changes of Selected Hematological Parameters in Trachemys Spp.

Abstract

This study focused on observation of seasonal changes of selected haematological parameters in Trachemys spp. The experiment involved 6 turtles of the same species and approximately the same size. From September 2017 to December 2018 on a monthly basis, the samples of turtle blood were collected and blood smears were made, which were subsequently evaluated by the light microscopy. During the period of observation, we focused on the changes in the percentage of individual types of cells in a leucogram. The most significant differences in the percentage of leukocytes were observed during hibernation and during the summer period. The blood profiles revealed that the most heterophilic granulocytes were most abundant in the summer, when their values reached 50 % of the leukocytes. Significant changes in the percentage of heterophilic and basophilic granulocytes occurred during the period of hibernation. The number of heterocytes during hibernation decreased to 30 %. On the contrary, the number of basophils increased significantly to 33 %. Eosinophilic granulocytes, lymphocytes, and monocytes did not show such notable changes. The results of the study demonstrated that in turtles of the Trachemys genus, changes in their leuco-grams occurred during the period of hibernation. These changes are important for the evaluation of health condition of the turtles, determination of the prognosis and the treatment.

Open access
Occurrence of Malassezia Spp. on Healthy Human Skin

Abstract

The genus Malassezia currently includes seventeen species that have been isolated from healthy and diseased human and other animal skin. Malassezia are implicated in a range of cutaneous diseases in humans: pityriasis versicolor, atopic or seborrheic dermatitis, dandruff, folliculitis and psoriasis. The outbreak of the disease depends on the interaction between the host immune system and Malassezia species. Malassezia stimulates both the cellular and humoral immune response in humans. Although Malassezia species have been associated with various dermatological diseases in people, the detailed pathological role of Malassezia remains obscured. Malassezia yeasts require lipids for their growth and therefore to a greater extent they colonize the sites with more sebaceous glands. The ecosystem on skin is complex and its balance depends on several factors. The aim of this study was to determine the presence of Malassezia yeasts in clinically normal skin of 42 healthy, randomly selected individuals of different ages. In the group of people examined, up to 30 persons (71.4 %) represented by children, adults and the elderly were positive to Malassezia yeasts. It has been shown that the back is an area with a higher incidence (66.7 %) of observed yeast compared to the head (40.5 %).

Open access
Optimal Criteria for the Selection of Probiotics, Based on their Mode of Action

Abstract

The objective of this review was to discuss some of the criteria which influence the selection of microorganisms with probiotic properties based on their mode of action. The most common bacteria that belong to the “group” probiotics are the Lactobacillus and Bifidobacterium species/strains. Probiotics have benefits and effects by their mechanism of action in different axial locations such as: producing substances, influencing immune function and response, modification as well as maintenance of a healthy population of microorganisms in the intestinal environment. Probiotics have demonstrated significant potential as therapeutic options for a variety of diseases Potential peripheral pathways that link probiotic ingestion in the brain function are focused on the role of the vagal afferent nerve signalling and changes in the cerebral levels of neuromodulators. The application of probiotic microorganisms represents a way to effectively influence the composition of the intestinal microbiome and the immune system of the host, as well as they can be considered as a suitable alternative to influence a healthy quality of life.

Open access
Periodontal Disease in Association with Systemic Diseases in the Dog

Abstract

Periodontal disease (PD) is the second most common disease affecting dogs in UK veterinary practices. Veterinary and human literature suggests that periodontal disease may be associated with bacteraemia and a chronic, systemic release of inflammatory mediators which produce direct or immune-mediated changes elsewhere in the body. Thirty canine periodontal patient’s electronic medical histories were analysed for comorbidities. The findings were analysed overall to identify any possible associations. Seventy three percent of these dogs had comorbidities, most commonly haematopoietic, cardiovascular, musculoskeletal and hepatic systems were involved. The most prevalent comorbidities were: high liver enzymes, heart murmur, mitral valve disease, and monocytosis. Other interesting comorbidities were: endocarditis, neutrophilia, submandibular lymph node enlargement and arthritis. Periodontal disease patients had a higher prevalence of disease when compared to the disease prevalence data for UK pet dogs in general. Mitral valve disease was over 17 times more likely in the periodontal disease patients. Comorbidity disease prevalence also increased with more severe periodontal disease stages. This study supports an association between periodontal disease and systemic diseases in the dog. Further studies should focus on confirming a cause and effect relationship. Until then, these data may be useful for veterinarians to examine periodontal patients for concurrent diseases and can be used as a tool to promote dental disease prevention to pet owners.

Open access