The dorsal skin structure contributes to the surface bacteria populations of Sunda Porcupine (Hystrix javanica)

FUNGAL FLORA OF ROSETTE QUILLS IN THE NORTH AMERICAN PORCUPINE (ERETHIZON DORSATUM) IN THE NORTHEASTERN UNITED STATES

The North American (NA) porcupine (Erethizon dorsatum) is a rodent species with specialized hair structures called quills designed to detach and penetrate into tissues of any human or animal coming into contact with them. The objective of this study was to characterize the fungal flora of the quills in the region of the rosette in wild NA porcupines to further define health risks to NA porcupines and any animal coming into contact with the quills. A total of 17 adult NA porcupines were sampled, and fungal culture was performed. Fungal organisms were cultured from 15 (88.2%) of 17 samples. Thirty-three isolates of 10 different fungal genera were cultured. The most frequently isolated fungi were Lodderomyces elongisporus (n = 7, 41.2%), Candida spp. (n = 3, 17.6%), and Penicillium spp. (n = 2, 11.8%). Eleven (64.7%) individuals grew multiple fungal organisms. In humans and animals quilled by porcupines, fungal culture should be considered in cases of infection, and if isolates resembling Candida spp. are isolated, matrix-assisted laser desorption-ionization time of flight or molecular methods are necessary to rule out L. elongisporus.

Determination of thick and thin fibres distribution in Sunda porcupine dorsal skin (Hystrix javanica) using Picrosirius red staining

The complexity of the Sunda porcupine skin has become an important topic due to the unique characteristics of its quill follicles. The structure and chemical composition of the skin has affected many physiological and other conditions. Generally, quills are larger, stronger and stiffer than hair; therefore, the skin structure needs to adapt to support their physiology. The strength of the skin is determined by its collagen composition and arrangement; therefore, this study aims to analyse the composition and distribution of thick and thin fibres based on the specific characteristics of Sunda porcupine skin under polarized light using picrosirius red staining. The skin samples used were from the thoracodorsal and lumbosacral regions of eight Sunda porcupine adults. The histological staining was carried out using the picrosirius red method, while the samples were observed under a polarized light microscope and analysed with software. The results showed that the skin is composed of 36%-65% thick fibres, 20%-35% thin fibres and small amounts of other types with the lumbosacral region having higher compositions of thick and thin fibres than those in the thoracodorsal region. Furthermore, the thoracodorsal and lumbosacral regions have the highest composition of thick fibre in the deeper dermis and quill follicle, respectively. These demonstrated that the complexity of the skin structure of Sunda porcupine due to its quill derivates correlated with its collagen composition and distribution.

Fatty acid composition profiling in the dorsal skin of Sunda porcupine (Hystrix javanica)

The fatty acid composition in the skin of Sunda porcupine (Hystrix javanica) is an interesting topic due to the special features of quills, especially in the dorsal region. Therefore, this study aims to analyze the composition of fatty acids in the dorsal region of Sunda porcupine skin. It was conducted using skin samples of the thoracodorsal and lumbosacral regions taken by biopsies and from frozen specimens. The skin lipid was extracted and then derivatized into fatty acid methyl ester before analyzing with gas chromatography mass spectrometry. The results showed that the skin is composed of up to 25 fatty acids ranging from C12 to C25 with various types but only 16 were found in both regions and sexes. Fatty acids with an antibacterial effect were found abundantly, such as oleic, palmitic, stearic, and linoleic acids. The total abundance in the thoracodorsal region was higher than lumbosacral, while the composition in male was higher than in female. Based on the results, the fatty acid composition in the dorsal skin region of Sunda porcupine consists of at least 16 types ranging from C12-C25. Additionally, the region and sex were observed to contribute significantly to the variation in skin fatty acid composition.

The influence of hydration status on ion transport in the rabbit (Oryctolagus cuniculus) skin-An in vitro study

The preservation of physiological transport of ions and water content is particularly important for maintaining the skin barrier, touch and pain stimuli, as well as the initiation of skin regeneration processes, especially after treatments associated with breaking skin continuity and wound healing difficulties. The aim of the study was to assess changes in ion transport, measured as values of transepithelial electric resistance and potential difference in stationary conditions and during mechanical-chemical stimulations, depending on the hydration status of isolated rabbit skin specimens. The specimens were divided into five groups: control (n = 22), dehydrated in 10% NaCl (n = 30), rehydrated after dehydration (n = 26), dried at 37°C (n = 26), and rehydrated after drying (n = 25). Dehydrated tissue samples showed altered resistance compared to the control; this change was maintained regardless of rehydration. In the dehydrated samples, changes in the measured electric potential were also noted, which returned to values comparable with the control after rehydration. Dehydrated skin, regardless of the cause of dehydration, responds with changes in the transport of sodium and chloride ions and the altered cellular microenvironment. It could influence the perception of stimuli, particularly pain, and slow down the regeneration processes.

Regional alopecia and dermatitis due to Lodderomyces elongisporus in a North American porcupine (Erethizon dorsatum)

BACKGROUND

Lodderomyces elongisporus is a yeast with a worldwide distribution that has been reported as a cause of infection in immunocompromised humans and in a dog that had been quilled by a porcupine.

OBJECTIVES

The objective of this report is to describe the clinical presentation, diagnosis and treatment of dermatitis caused by L. elongisporus in a North American porcupine (Erethizon dorsatum).

ANIMAL

One wild adult male North American porcupine from New York state, USA.

METHODS AND MATERIALS

The porcupine was presented for alopecia and scaling dermatitis over the caudal dorsum. Diagnostic testing included cytological evaluation, trichogram, bacterial and fungal culture, and histopathological examination of skin biopsies.

RESULTS

Histopathological findings from skin specimens demonstrated mild eosinophilic perivascular-to-interstitial dermatitis with superficial dermal fibrosis, mild epidermal hyperplasia with moderate-to-marked intracorneal and intrafollicular yeast. Fungal culture with matrix-assisted laser desorption/ionization confirmed L. elongisporus as the cause of the dermatitis. The porcupine was treated with a six week course of oral itraconazole with clinical resolution.

CLINICAL RELEVANCE

Infection with L. elongisporus should be included as a differential diagnosis for North American porcupines exhibiting signs of dermatitis including scaling and alopecia. This case report may be relevant for the diagnosis and treatment of porcupines with dermatitis and for animals or humans that have been quilled by a porcupine.

Localization of uncoupling protein 1 (UCP-1) in the sebaceous gland of the dorsal region in the Sunda porcupine (Hystrix javanica)

Uncoupling protein 1 (UCP-1) was believed to be an exclusive protein found in the brown adipose tissue of small rodents and humans; however, recent studies show that the expression of UCP-1 protein has been found in the sebaceous glands of the mouse tail and human skin. There are a few reports about the presence of UCP-1 in the sebaceous glands of other rodents, such as the Sunda porcupine (Hystrix javanica), a wild spiny rodent commonly found in Indonesia with a large sebaceous gland. The aim of this study was to identify the presence of UCP-1 in the sebaceous glands on the skin of the Sunda porcupine. The skin from three regions (thoracodorsal, lumbosacral and apex caudal) of eight adult Sunda porcupines was used to detect UCP-1-immunopositive cells through immunohistochemistry. All three regions were found immunopositive to anti-UCP-1 antibody in the sebaceous gland of quill and hair follicles, and the epidermal layer in quill and hair follicles with various intensities. The result of immunohistochemistry revealed that the thoracodorsal and apex caudal region was the most intense immunoreaction followed by the lumbosacral region. These findings proved that the presence of UCP-1 was also identified in the sebaceous glands of other rodent (Hystrix javanica) and regions of the body, which has not been reported previously.

Morphological evaluation of polysaccharide content and collagen composition during cutaneous wound healing in the Sunda porcupine (Hystrix javanica)

Wound healing in the Sunda porcupine is believed to occur quickly, although the wound is large and severe. Wound enclosure involves many processes to restore the lost or damaged skin structure where conjugated polysaccharide-protein and collagen, as the main components deposited in wound tissue to restore it. The aim of this study was to evaluate alteration of polysaccharide contents and collagen in untreated full-thickness wound healing in the thoracodorsal and lumbosacral regions in the Sunda porcupines. Histological analysis was performed by periodic acid Schiff, alcian blue pH 2.5, picrosirius red staining method and Low Vacuum Scanning Electron Microscope (LV-SEM) imaging to obtain the fundamental data of healing process. Wound healing began with re-epithelization followed by progressive wound contraction with 4 overlapping stages in about 30–50 days until the wound closed (21–30 days in thoracodorsal and 30–50 days in lumbosacral). Neutral polysaccharide was more widely distributed compared to the acid polysaccharide in almost all stages of wound healing. The ratio of collagen I to III appeared to be higher in the thoracodorsal region than the lumbosacral region during healing process. LV-SEM imaging showed changes in connective tissue structure in the wound border and granulation tissue which appeared abundant and mixed of thin and thick fiber. In conclusion, cutaneous full thickness wound healing in the Sunda porcupine occurred faster in the thoracodorsal region, which might be correlated to the role of neutral polysaccharide and a high ratio of collagen I to III.