Evaluation of trace elements, oxidant/antioxidant status, vitamin C and β-carotene in dogs with dermatophytosis

Remarkable Phenotypic Virulence Factors of Microsporum canis and Their Associated Genes: A Systematic Review

Microsporum canis is a widely distributed dermatophyte, which is among the main etiological agents of dermatophytosis in humans and domestic animals. This fungus invades, colonizes and nourishes itself on the keratinized tissues of the host through various virulence factors. This review will bring together the known information about the mechanisms, enzymes and their associated genes relevant to the pathogenesis processes of the fungus and will provide an overview of those virulence factors that should be better studied to establish effective methods of prevention and control of the disease. Public databases using the MeSH terms "Microsporum canis", "virulence factors" and each individual virulence factor were reviewed to enlist a series of articles, from where only original works in English and Spanish that included relevant information on the subject were selected. Out of the 147 articles obtained in the review, 46 were selected that reported virulence factors for M. canis in a period between 1988 and 2023. The rest of the articles were discarded because they did not contain information on the topic (67), some were written in different languages (3), and others were repeated in two or more databases (24) or were not original articles (7). The main virulence factors in M. canis are keratinases, fungilisins and subtilisins. However, less commonly reported are biofilms or dipeptidylpeptidases, among others, which have been little researched because they vary in expression or activity between strains and are not considered essential for the infection and survival of the fungus. Although it is known that they are truly involved in resistance, infection and metabolism, we recognize that their study could strengthen the knowledge of the pathogenesis of M. canis with the aim of achieving effective treatments, as well as the prevention and control of infection.

A Randomized Controlled Trial to Evaluate the Impact of a Novel Probiotic and Nutraceutical Supplement on Pruritic Dermatitis and the Gut Microbiota in Privately Owned Dogs

Pruritic dermatitis (PD) is a common presentation of canine allergic skin diseases, with diversity in severity and treatment response due to complex etiopathogenesis. Evidence suggests the gut microbiota (GM) may contribute to the development of canine allergies. A 10-week double-blind randomized controlled trial evaluated a novel probiotic and nutraceutical blend (PNB) on clinical signs of skin allergy, health measures, and the GM of privately owned self-reported pruritic dogs. A total of 105 dogs were enrolled, with 62 included in pruritus and health analysis and 50 in microbiome analysis. The PNB supported greater improvement of owner-assessed clinical signs of PD at week 2 than the placebo (PBO). More dogs that received the PNB shifted to normal pruritus (digital PVAS10-N: <2) by week 4, compared to week 7 for the PBO. While a placebo effect was identified, clinical differences were supported by changes in the GM. The PNB enriched three probiotic bacteria and reduced abundances of species associated with negative effects. The PBO group demonstrated increased abundances of pathogenic species and reduced abundances of several beneficial species. This trial supports the potential of the PNB as a supplemental intervention in the treatment of PD; however, further investigation is warranted, with stricter diagnostic criteria, disease biomarkers and direct veterinary examination.

Effect of parity on non-esterified fatty acid, oxidant/antioxidant status, and zinc and copper levels around periparturient period in Beetal goats of Himalayan Region

The study was conducted to evaluate the effect of parity and physiological status on non-esterified fatty acid (NEFA), oxidative stress, and zinc and copper levels among the Beetal breed of goat. Thirty dual-purpose Beetal goats reared under the semi-intensive system were selected and based on parity were divided into three groups with 10 animals each viz. Early parity (EP; ≤2 parity), mid parity (MP; 3-6 parity), and late parity (LP; ≥7 parity). Blood samples were collected 3 weeks and 1 week pre-kidding followed by 1, 2, 4, and 8 weeks post-kidding for the estimation of NEFA, oxidant (malondialdehyde [MDA], antioxidant (superoxide dismutase [SOD], catalase [CAT], glutathione [GSH], glutathione peroxidase [GSH-Px], and glutathione S-transferase [GST]), and zinc and copper levels. Significant (p < 0.01) increase was observed in NEFA and MDA levels as the goats approached kidding and continued till 2 weeks post-kidding in MP and LP and 1 week post-kidding in EP goats. Significant decrease in SOD (p < 0.05), CAT (p < 0.05), GSH-Px (p < 0.01), GSH (p < 0.01), and GST (p < 0.05) activities were observed as goats approached kidding and continued to decrease up to 2 weeks post-kidding. Zinc and copper levels showed a significant decline from 3 weeks pre-kidding to 2 weeks post-kidding in MP and LP and 1 week post-kidding in EP goats. A significant effect of parity was observed on MDA (p < 0.05), GSH (p < 0.05), and GSH-Px (p < 0.05) activities only; however, parity × sampling time interaction was observed in all the parameters. Findings highlight a different metabolic, trace mineral (zinc and copper), and oxidative response around the periparturient period in Beetal goats, with the EP goats, responding first to increased metabolic and oxidative stress and also first to recover from oxidant/antioxidant imbalance.

Circulating redox status in sheep naturally infected with Trichophyton verrucosum

Trichophyton verrucosum is a zoophilic dermatophyte that causes skin inflammation. The present study aimed to evaluate the redox status in the blood of sheep clinically infected with T. verrucosum. According to clinical and mycological investigations, 48 juvenile male Balady sheep were selected in their natural habitat and divided into four groups depending on the lesion size: mild (MID), moderate (MOD), severe (SEV) T. verrucosum infection, and healthy control groups. Compared to the controls, plasma superoxide anion increased (P < 0.05) in both MOD and SEV but total peroxides (TPx) gradually increased (P < 0.05) in MID followed by MOD and SEV. Superoxide dismutase and total antioxidant capacity (TAC) were higher (P < 0.05) in MID and lower (P < 0.05) in MOD and SEV than in controls, but SEV showed lower TAC than MOD. Malondialdehyde (MDA, a lipid peroxide marker) increased (P < 0.05) in SEV than in controls, but protein carbonyl (PC, a protein peroxidation marker) was augmented (P < 0.05) as lesions progressed from mild to severe. The oxidative stress index (TPx/TAC ratio) progressively increased (P < 0.05) in MOD and SEV. The correlation of PC was positive with TPx and negative with TAC (P < 0.01). In conclusion, sheep infection with T. verrucosum is characterized by increased TPx and decreased TAC in plasma depending on the lesion area. The redox status is shifted towards the oxidizing state, particularly in MOD and SEV cases. This results in a condition of OS, which may contribute to the pathogenesis of the disease.

Molecular Identification and Antifungal Susceptibility Patterns of Dermatophytes Isolated from Companion Animals with Clinical Symptoms of Dermatophytosis

Introduction

Dermatophytosis is a common skin disease in cats and dogs caused by Microsporum and Trichophyton fungi. Species identification and knowledge of their antifungal susceptibility are therapeutically and epidemiologically important. This study assessed the prevalence of feline and canine dermatophytosis in Iran, identified the aetiological agents molecularly and tested their antifungal susceptibility.

Material and Methods

A total of 308 companion animals (134 dogs and 174 cats) with skin lesions were examined from March 2015 to March 2018. Hair and skin samples were examined by microscopy with 20% KOH and cultured on Sabouraud dextrose agar with cycloheximide and chloramphenicol. Fungal isolates were confirmed by sequencing of the internal transcribed spacer (ITS) r-DNA region. The antifungal susceptibility of dermatophytes was tested by broth microdilution assay using standard drugs.

Results

Dermatophytes were found in 130 (42.2%) samples, 62 of them feline and 68 canine. Based on sequencing of all strains, M. canis (78.5%, P<0.05), M. gypseum (10.7%), and T. mentagrophytes (10.7%) were the dermatophytes isolated. The non-dermatophyte species Nannizziopsis vriesii was also isolated from two feline dermatomycosis cases. Dogs and cats younger than one year (61.5%) showed a statistically significantly higher prevalence of infection (P<0.05). Caspofungin produced the lowest geometric mean MIC at 0.0018 μg/mL, followed by ketoconazole, terbinafine, itraconazole, miconazole, griseofulvin, clotrimazole and fluconazole, in a 0.038–1.53 μg/mL range.

Conclusion

This is the first molecular study to identify the causes of pet dermatophytosis in north-western Iran. ITS-PCR was shown to be a useful and reliable method for the identification of closely related species of dermatophytes in clinical and epidemiological settings. The lowest MIC of caspofungin indicated that this drug was the most potent in vitro.

Host-Parasite Interaction in Sarcoptes scabiei Infestation in Porcine Model with a Preliminary Note on Its Genetic Lineage from India

Simple Summary

Scabies or mange caused by Sarcoptess cabiei is the latest addition of WHO’s list oftropical neglected diseases. It causes severe itching to the host. It has a wide host range including humans, farm animals, companion animals, and wild animals. It is anemerging/re-emerging disease with high prevalence in underdeveloped and developing countries. The disease has zoonotic importance and is of significant public health concern as cross-transmission or species jumping is very common. To date, fifteen Sarcoptes varieties have been reported as per host origin. Differential diagnosis at variety level is very crucial for epidemiological study and scratching future eradication program of the disease. As morphotaxonomy fails to differentiate varieties, use of molecular markers is crucial. Moreover, it is very important to understand the host-parasite interaction at the systemic level for a better understanding on the pathogenicity of the disease. Here, we report the genetic characterization of S. scabiei from India and host-parasite interaction in a porcine model.

Abstract

The burrowing mite Sarcoptes scabiei causes scabies in humans or mange in animals. It infests a wide range of mammalian species including livestock, companion animals, wild animals, and humans. Differential diagnosis of Sarcoptes varieties is key for epidemiological studies and for formulation of an eradication program. Host-parasite interaction at the systemic level is very important to understand the pathogenicity of the mite. This communication deals with the preliminary report on the genetic characterization of S. scabiei from India. Moreover, the effect of S. scabiei infestation on host physiology with special emphasis on serum biochemical parameters, lipid profile, oxidant/antioxidant balance, stress parameters, and immune responses were evaluated in a porcine model. Cytochrome C oxidase 1 and voltage-sensitive sodium channel based phylogenetic study could distinguish human and animals isolates but could not distinguish host or geographical specific isolates belonging to animal origin. An absence of host-specific cluster among animal isolates argues against the hypothesis of delineating S. scabiei as per host origin. Elevated levels of markers of liver function such as albumin, AST, ALT, ALP, and LDH in infested animals indicated impaired liver function in infested animals. S. scabiei infestation induced atherogenic dyslipidemia indicated by elevated levels of total cholesterol, low-density lipoprotein cholesterol and triglycerides, and a decreased level of high-density lipoprotein cholesterol. Oxidative stress in infested animals was indicated by a high level of nitric oxide and serum MDA as oxidative stress markers and low antioxidant capacity. S. scabiei triggered stress response and elevated levels of serum cortisol and heat shock proteins were recorded in infested animals. S. scabiei infestation increased the serum concentration of immunoglobulins and was associated with up-regulation of IL-2, IFN-γ, IL-1β, and IL-4 indicating both Th1 and Th2 response. The results of the study will be helpful for a better understanding of host-parasite interaction at the systemic level in crusted scabies in pigs.

The therapeutic efficacy of Aloe vera gel ointment on staphylococcal pyoderma in dogs

BACKGROUND AND AIM

Staphylococcus pyoderma is a common problem in dogs that need a novel treatment rather than antibiotic therapy. The aim of this study was to investigate the therapeutic efficacy, anti-inflammatory, and antioxidative properties of Aloe vera (Aloe barbadensis) gel ointment on dogs' Staphylococcus pyoderma compared to gentamicin ointment.

MATERIALS AND METHODS

The inhibition zone of A. vera extract 20% and 40% and gentamicin 1% against Staphylococcus aureus was determined on well diffusion agar. Twenty Baladi local breed dogs were used as control negative group before intradermal inoculation with 105 CFU S. aureus. The animals were classified into four equal groups, control positive group without treatment (n=5), treated groups by 20% A. vera gel ointment (n=5), 40% A. vera gel ointment (n=5), and gentamicin ointment 1% (n=5). Topical application of A. vera and gentamicin ointments was carried out twice daily for 2 weeks until complete healing of dogs' pyoderma. Clinical evaluation was recorded. Inflammatory, oxidant, and antioxidant parameters were measured in serum.

RESULTS

The inhibition zone of A. vera extracts 20% and 40% was 19 mm and 23 mm, respectively, while gentamicin 1% was 18 mm. The half maximal inhibitory concentration (of A. vera 20% and 40% were 13.70 with R2=0.98. Dogs' pyoderma treated with A. vera gel ointment 20% and 40% were more likely to have low haptoglobin and tumor necrosis factor-α concentrations than gentamicin 1% ([odds ratio [OR]=4.6; 95% confidence interval [CI]=1.31-17.40; p<0.05]; [OR=5.2; 95% CI=1.04-22.30; p<0.05]), respectively.

CONCLUSION

It seems evident that A. vera has therapeutic effect, antibacterial, and anti-inflammatory effects against dogs' staphylococcal pyoderma than gentamicin that would support its further use rather than antibiotics in one health arena.

Canine demodicosis: Hematological and biochemical alterations

Background and Aim:

One of the most common cutaneous infections seen in veterinary canine practice is canine demodicosis. Demodicosis is a parasitic skin infection with a possible impact on acute-phase proteins (APPs) and oxidant-antioxidant balance. This study aimed to estimate the possible alterations in hematological, biochemical, oxidant-antioxidant, and APP (C-reactive protein [CRP] and albumin) profiles in naturally infected dogs with demodicosis.

Materials and Methods:

This study enrolled 21 dogs that were divided into two groups: The control group including 7 apparently healthy dogs and the diseased group including 14 dogs with generalized demodicosis. Demodicosis was confirmed through microscopic detection. Blood samples were collected for the estimation of CBC, total protein, albumin, alanine transaminase, aspartate aminotransferase, blood urea nitrogen, creatinine, superoxide dismutase (SOD), glutathione peroxidase (GPx), total antioxidant capacity (TAC), catalase (CAT), malondialdehyde (MDA), and CRP levels.

Results:

Significant reduction in red blood cells along with significant elevation in white blood cells was recorded in the diseased group compared with the control group. There was also significant elevation in MDA, TAC, SOD, and CRP levels along with significant reduction in GSH-Px and CAT levels in the diseased group.

Conclusion:

Based on these findings, a relationship between canine generalized demodicosis and oxidant-antioxidant disequilibrium could be suggested. Evidence of this relation manifested in the elevation in MDA and SOD levels and reduction in GPx and CAT levels as a consequence to the release of ROS resulting from Demodex infection. CRP elevation is expected in canine demodicosis.