Search Results (18)

This study evaluated the effects of dietary lysine supplementation in low-protein diets on nutrient digestibility, nitrogen metabolism, growth performance, serum biomarkers, and pelt quality in female blue foxes (Alopex lagopus) during the fur-growing period. A total of 105 18-week-old female blue foxes were randomly assigned to seven groups (n = 15 per group). The control group received a standard-protein diet (28% dry matter, DM), while six experimental groups were fed low-protein diets (26% DM) supplemented with 0%, 0.2%, 0.4%, 0.6%, 0.8%, and 1.0% lysine, corresponding to total lysine levels of 0.75%, 0.95%, 1.15%, 1.35%, 1.55%, and 1.75% DM, respectively. Lysine supplementation at 1.35% and 1.55% DM significantly improved the digestibility of ether extract and amino acids, including aspartic acid, glycine, methionine, isoleucine, and tyrosine (p < 0.05). Nitrogen retention increased accordingly, indicating enhanced dietary utilization (p < 0.05). Daily weight gain, particularly from day 15 to day 30, was significantly higher in 1.15–1.55% lysine groups compared to low-lysine groups (p < 0.05), achieving growth performance comparable to the control (p > 0.05). Serum total protein and albumin concentration were significantly improved with increasing lysine levels in low-protein groups (p < 0.01), aligning with those of the control group (p > 0.05). Furthermore, high lysine supplementation significantly improved pelt quality, as evidenced by the increased underfur length and decreased guard hair/underfur in 1.35–1.75% DM (p < 0.05). These findings suggest that lysine supplementation in low-protein diets supports nutrient utilization, growth performance, and metabolic health status while reducing dietary protein content. The optimal dietary lysine range is 1.15% to 1.55% DM (corresponding to 0.4% to 0.8% in air-dry basis), with 1.35% DM (corresponding to 0.6% in air-dry basis) identified as the most suitable level for balancing growth, nitrogen excretion, and pelt quality in fur-growing female blue foxes. Full article

Intestinal flora plays an important role in maintaining the internal stability and health of the intestine. Currently, intestinal microbes are considered an important “organ” but are mostly ignored by people. This study evaluated the flora structure of each intestinal segment of blue foxes pre-weaning and explored the differences between the fecal flora and intestinal flora structure of each segment after weaning. Samples of intestinal contents from three blue foxes at 45 days of age (before weaning) and intestinal contents and feces samples from at 80 days (after weaning) were collected for 16s rRNA flora analysis. The species and distribution characteristics of microorganisms in different intestinal segments of blue foxes before and after weaning were different. Except for the rectum, the dominant flora of each intestinal segment of blue fox changed significantly after experiencing weaning, and the fecal flora structure of young fox at the weaning stage did not represent the whole intestinal flora structure but was highly similar to that of the colon and rectum. To sum up, the intestinal flora of blue foxes changed systematically before and after weaning. When performing non-invasive experiments, the microflora structure of the colon and rectum of blue foxes can be predicted by collecting fecal samples. Full article

Butea monosperma (Fabaceae) has been used in traditional Indian medicine to treat a variety of ailments, including abdominal tumors. We aimed to investigate the anti-IL-6 activity of butein in ovarian cancer and elucidate the underlying molecular mechanisms. Butein was isolated and identified from B. monosperma flowers, and the inhibition of IL-6 signaling was investigated using the HEK-Blue™ IL-6 cell line. The surface plasmon resonance assay was used to estimate the binding of butein to IL-6, IL-6Rα, and gp130. After treatment with butein, ovarian cancer cell migration, apoptosis, and tumor growth inhibition were evaluated in vitro and in vivo. Furthermore, we used STAT3 siRNA to identify the mechanistic effects of butein on the IL-6/STAT3/FoxO3a pathway. Butein suppressed downstream signal transduction through higher binding affinity to IL-6. In ovarian cancer, butein inhibited cell proliferation, migration, and invasion, and induced cell cycle arrest and apoptosis. In addition, it decreased the growth of ovarian cancer cells in xenograft tumor models. Butein inhibited STAT3 phosphorylation and induced FoxO3a accumulation in the nucleus by inhibiting IL-6 signaling. The anticancer activity of butein was mediated by blocking the IL-6/IL-6Rα interaction and suppressing IL-6 bioactivity via interfering with the IL-6/STAT3/FoxO3a pathway. Full article

A 3 × 3 factorial experiment was conducted to investigate the influence of dietary calcium, phosphorus, and vitamin D₃ (VD₃) supplement levels on the growth performance, nutrient digestibility, and serum biochemical indices of growing-furring blue foxes. One hundred and thirty-five 120-day-old male blue foxes were randomly allocated into nine groups. The nine treatment diets were supplemented with 0%, 0.4%, or 0.8% Ca, and 1000, 2000, or 4000 IU·kg⁻¹ VD₃. The base diet contained 0.8% Ca and 327 IU·kg⁻¹ VD₃. The dietary calcium level had a significant effect on the average daily gain (ADG) of blue foxes at 121 to 135 days of age and 136 to 150 days (p < 0.05). The ADG of blue foxes at 121 to 135 days of age was significantly decreased by VD₃ level (p < 0.05). The Ca dosage decreased the nutrient digestibility (p < 0.05). The Ca dosage increased the fecal Ca and P and decreased the P digestibility (p < 0.05). Interactions were found between the Ca and VD₃ levels, which affected the digestibility of Ca and P (p < 0.05). In conclusion, this research determined the suitable doses of Ca and VD₃ for growing-furring blue foxes. Full article

Getah virus (GETV) is a zoonotic virus transmitted by mosquitoes, belonging to the Togaviridae family, Alphavirus genus. It was first isolated from mosquitoes in Malaysia in 1955, being widespread in island countries in the South Pacific region. Since the beginning of the 21st century, GETV expanded its range and geographical distribution from low-latitude tropical regions to 60° north latitude, being isolated from 17 different species of mosquitoes belonging to five genera of Culicidae (Culex, Anopheles, Armigeres, Aedes and Mansonia), as well as from midges in Eurasia. Molecular genetic evolution analysis revealed large molecular differences between the mosquitoes currently circulating Eurasia and those in the South Pacific in 1950s. The number of disease outbreaks caused by GETV in animals is increasing alongside the types of animals infected, from horses and pigs to cattle, blue foxes and red pandas. The disease burden is severely underestimated, and the economic cost to livestock production remains unknown. Herein, we review GETV temporal and spatial distribution, molecular genetic evolution, transmission and data on disease outbreaks. This work provides a reference for public health workers engaged in GETV research and zoonotic disease prevention and control. Full article

Based on the randomized design, a 3 × 3 factorial experiment was designed to examine the effects of dietary calcium (Ca), phosphorus (P), and vitamin D₃ (VD₃) supplemental levels with a fixed 1.5/1 ratio of Ca to P on the growth performance, nutrient digestibility, and serum biochemical indices blue foxes’ growth. In total, 135 male blue foxes with the age of 60 days were randomly divided into 9 groups each with 15 blue foxes. The blue foxes belonging to the nine treatment groups were fed Ca supplementation (0%, 0.4%, or 0.8%) and VD₃ supplementation (1000, 2000, or 4000 IU/kg DM). The base diet contained 0.8% Ca and 327 IU/kg VD₃. The dosage of VD₃ in blue foxes showed a significant impact on their growth performance (p < 0.05). The Ca dosage had a linear effect on the digestibility of the CP and carbohydrates (CHO) (p < 0.05). In conclusion, the results indicated that the Ca and VD₃ doses showed promising effects on growth performance and nutrient digestibility in growing blue foxes and could reduce fecal N and P via improvement in protein and P utilization. Full article

Dietary protein is a key nutritional parameter and warrants special attention in animal husbandry. This study aimed to evaluate the effect of replacing fish meal (F) with fly maggot protein (M) on the growth performance, antioxidant levels, immune indexes, and fecal microflora in weaned blue foxes (Alopex lagopus). Twenty weaned blue foxes were randomly assigned to the control (F diet; 6% of F) or experimental (M diet; F substituted by M) group (10 blue foxes per group). The duration of the trial was 28 days. The results showed that there was no significant difference in average daily gain between group M and group F during the experiment (p = 0.473). Moreover, the diarrhea index was similar between group M and group F during the entire experimental period (p = 0.112). At the end of the experiment, the levels of IL-6 and IgG in group M at 28 d were significantly higher than that in group F (p = 0.004, p = 0.025, respectively), but not IL-1β, IL-2, SIgA, IgM, and TNF-α. The levels of SOD in group M at 28 d were significantly higher than those in group F (p = 0.001), and no difference of MDA and T-AOC was found between group F and M (p = 0.073, p = 0.196, respectively). In both groups, the diversity of fecal microbes first increased and then decreased with the progress of the experimental period. Initially, there were differences in the composition of microbial communities between the two groups. However, this difference was attenuated at later stages of the experimental period. In conclusion, fly maggot protein can replace fish meal as a source of animal protein in feed material for blue foxes during the weaning period. Full article

While harmful effects of blue light on skin cells have been recently reported, there are few studies regarding natural products that alleviate its negative effects. Therefore, we investigated ameliorating effects of yellow chaste weed (YCW) (Helichrysum arenarium) extract and its components, apigenin and galangin, on blue light-irradiated HaCaT cells. In this study, we found that YCW extract improved the reduced proliferation of HaCaT cells induced by blue light-irradiation and reduced blue light-induced production of reactive oxygen species (ROS) levels. We also found that apigenin and galangin, the main components of YCW extract, showed the same activities as YCW extract. In experiments examining molecular mechanisms of YCW extract and its components such as apigenin and galangin, they all reduced expression of transient receptor potential vanilloid member 1 (TRPV1), its phosphorylation, and calcium ion (Ca²⁺) influx induced by blue light irradiation. In addition, apigenin and galangin regulated phosphorylation of mitogen-activated protein kinases (MAPKs). They also reduced phosphorylation of mammalian sterile 20-like kinase-1/2 (MST-1/2), inducing phosphorylation of Akt (protein kinase B), one downstream molecule of MST-1/2. Moreover, apigenin and galangin promoted translocation of Forkhead box O3 (FoxO3a) from the nucleus to the cytosol by phosphorylating FoxO3a. Besides, apigenin and galangin interrupted blue light influences on expression of nuclear and secretory clusterin. Namely, they attenuated both upregulation of nuclear clusterin and downregulation of secretory clusterin induced by blue light irradiation. We also found that they downregulated apoptotic protein Bcl-2 associated X protein (Bax) and conversely upregulated anti-apoptotic protein B-cell lymphoma 2 (Bcl-2). Collectively, these findings indicate that YCW extract and its components, apigenin and galangin, antagonize the blue light-induced damage to the keratinocytes by regulating TRPV1/clusterin/FoxO3a and MAPK signaling. Full article

FoxL1⁺-Telocytes (TC^FoxL1+) are subepithelial cells that form a network underneath the epithelium. We have shown that without inflammatory stress, mice with loss of function in the BMP signalling pathway in TC^FoxL1+ (BmpR1a^ΔFoxL1+) initiated colonic neoplasia. Although TC^FoxL1+ are modulated in IBD patients, their specific role in this pathogenesis remains unclear. Thus, we investigated how the loss of BMP signalling in TC^FoxL1+ influences the severity of inflammation and fosters epithelial recovery after inflammatory stress. BmpR1a was genetically ablated in mouse colonic TC^FoxL1+. Experimental colitis was performed using a DSS challenge followed by recovery steps to assess wound healing. Physical barrier properties, including mucus composition and glycosylation, were assessed by alcian blue staining, immunofluorescences and RT-qPCR. We found that BmpR1a^ΔFoxL1+ mice had impaired mucus quality, and upon exposure to inflammatory challenges, they had increased susceptibility to experimental colitis and delayed healing. In addition, defective BMP signalling in TC^FoxL1+ altered the functionality of goblet cells, thereby affecting mucosal structure and promoting bacterial invasion. Following inflammatory stress, TC^FoxL1+ with impaired BMP signalling lose their homing signal for optimal distribution along the epithelium, which is critical in tissue regeneration after injury. Overall, our findings revealed key roles of BMP signalling in TC^FoxL1+ in IBD pathogenesis. Full article

Welfare studies of blue foxes would benefit from a measurement of faecal cortisol metabolites (FCMs) as a non-invasive, physiological stress parameter reflecting hypothalamus–pituitary–adrenal (HPA) axis activity. Before implementation, a species-specific validation of such a method is required. Therefore, we conducted a physiological validation of an enzyme immunoassay (EIA) to measure FCMs in blue foxes. Twenty individuals (nine males and eleven females) were injected with synthetic adrenocorticotrophic hormone (ACTH) and faecal samples were collected every third h for two days. The FCM baseline levels were assessed based on the first sampling day (control period, 144 samples), followed by the ACTH injection and the second day of sampling (treatment period, 122 samples). FCMs were analysed with a 5α-pregnane-3ß,11ß,21-triol-20-one EIA. We compared the estimated mean FCM concentrations of the treatment samples to the baseline average. All samples for the two periods were collected at the same time of the day, which enabled to test the data also with an hourly pairwise comparison. With the two statistical approaches, we tested whether a possible diurnal fluctuation in the FCM concentrations affected the interpretation of the results. Compared to the baseline levels, both approaches showed 2.4–3.2 times higher concentrations on time points sampled 8–14 h after the ACTH injection (p < 0.05). The estimated FCM concentrations also fluctuated slightly within the control period (p < 0.01). Inter-individual variations in FCM levels were marked, which highlights the importance of having a sufficient number of animals in experiments utilising FCMs. The sampling intervals of 3 h enabled forming of informative FCM curves. Taken together, this study proves that FCM analysis with a 5α-pregnane-3ß,11ß,21-triol-20-one EIA is a valid measurement of adrenocortical activity in the farmed blue foxes. Therefore, it can be utilised as a non-invasive stress indicator in future animal welfare studies of the species. Full article

The blue fox (Vulpes lagopus), a fur-bearing animal, is an important component of the breeding industry in China. Semen quality is a key factor for the reproductive process and the breeding effectiveness of the farmed blue fox. However, bacterial contamination in semen samples utilized in artificial fertilization is very common. The β-defensins, a class of important antimicrobial peptides in mammals, could protect the reproductive system of male animals from bacterial invasion, maintain the stability of the genital tract microenvironment and improve semen quality. In this study, molecular cloning and bioinformatics analysis were conducted to analyze the protein structure and function of blue fox β-defensin 108 (Vulpes lagopus beta-defensin 108, vBD108) and 122 (Vulpes lagopus beta-defensin 122, vBD122). To evaluate the bacteriostatic effect of recombinant vBDs (Vulpes lagopus beta-defensins) protein, varying concentrations (0, 25, 50, 100, 200 µg/mL) were taken to evaluate the effects on Escherichia coli and Staphylococcus aureus at different times (0, 2, 4, 6, 8, 12 h). The results showed that vBD108 and vBD122 existed in different forms in protein structure and had antibacterial activity. Both proteins, at 50 µg/mL, had efficacious bacteriostatic activity. This study shows that recombinant vBD108 and vBD122 proteins have good antibacterial activity in vitro. This implies a potential role in improving semen quality and hygienic measures in the process of artificial insemination as an extender of semen dilution with antibacterial activity. Full article

For the last 13 years, the fur industry in Europe has suffered from epidemic spouts of a severe necrotizing pyoderma. It affects all species currently farmed for fur and causes animal welfare problems and significant losses to the farmers. The causative agent of this disease was identified as Arcanobacterium phocae. Previously, this bacterium has been isolated from seals and other marine mammals, apparently causing wound and lung infections. Attempts at antibiotic treatment have been unsuccessful and the current advice on preventing the disease is to cull all animals with clinical signs. This poses an urgent question regarding possible vaccine development, as well as the need for further understanding of the pathogenicity of this organism. This study compared the whole genomes of 42 A. phocae strains isolated from seals, blue foxes, finnraccoons, mink and otter. The sequences were created using the Illumina technology and annotations were done using the RAST pipeline. A phylogenetic analysis identified a clear separation between the seal strains and the fur-animal-derived isolates, but also indicated that the bacterium readily adapts to new environments and host species with reasonable diversity. A pan- and core-genome was created and analyzed for proteins. A further analysis identified several virulence factors as well as multiple putative and secreted proteins of special interest for vaccine development. Full article

A cytogenetic assay based on fragile sites (FS) enables the identification of breaks, chromatid gaps, and deletions. In healthy individuals, the number of these instabilities remains low. Genome stability in these species is affected by Robertsonian translocations in the karyotype of the blue fox and by B chromosomes in the silver fox. The aims of the study were to characterise the karyotype of blue foxes, silver foxes, and their hybrids and to identify chromosomal fragile sites used to evaluate genome stability. The diploid number of A chromosomes in blue foxes ranged from 48 to 50, while the number of B chromosomes in silver foxes varied from one to four, with a constant number of A chromosomes (2n = 34). In interspecific hybrids, both types of karyotypic variation were identified, with the diploid number of A chromosomes ranging from 40 to 44 and the number of B chromosomes varying from 0 to 3. The mean frequency of FS in foxes was 4.06 ± 0.19: 4.61 ± 0.37 in blue foxes, 3.46 ± 0.28 in silver foxes, and 4.12 ± 0.22 in hybrids. A relationship was identified between an increased number of A chromosomes in the karyotype of the hybrids and the frequency of chromosomal breaks. The FS assay was used as a biomarker for the evaluation of genomic stability in the animals in the study. Full article

The results presented in this study are the first such extensive characterization of the sperm morphometry of the blue fox (Alopex lagopus) and silver fox (Vulpes vulpes), as representatives of the family Canidae. Canine spermatozoa, especially the sperm of farmed foxes, are not often described in studies on reproduction. The aim of the study was a detailed comparison of the morphometric dimensions and shape of the sperm of two fox species: silver fox and blue fox. Semen collected from 10 silver foxes and 10 blue foxes was used for the study. The specimens were stained with silver nitrate. Measurements were performed of the length, width, perimeter, and area of the head; the area of the acrosome and its coverage; the length of the midpiece and its coverage; the length of the tail; and the length of the end piece of the tail. In addition, four head shape indices were calculated: ellipticity, elongation, roughness and regularity. The following values for the morphometric parameters and shape indices were obtained for blue fox and silver fox, respectively: head length—6.72 µm and 6.33 µm; head width—4.54.µm and 4.21 µm; head perimeter—18.11 µm and 17.37 µm; head area—21.94 µm² and 21.11 µm²; acrosome area—11.50 µm² and 10.92 µm²; midpiece length—12.85 µm and 12.79 µm; tail end piece length—3.44 µm and 3.28 µm; tail length—65.23 µm and 65.09 µm; acrosome coverage—52.43% and 52.83%; midpiece coverage—19.71% and 19.65%; sperm length—71.95 µm and 71.42 µm; ellipticity—1.49 and 1.52; elongation—0.19 and 0.20; roughness—0.84 and 1.88; regularity—1.09 and 0.99. The significance of differences between species was verified by Tukey’s test at p ≤ 0.05. Statistically significant differences between species were found for the following parameters: head length, width, perimeter and area; acrosome area; tail, end piece, and total sperm length; roughness and regularity. The differences in the size and shape of sperm can be used to establish reference patterns for fox sperm enabling more accurate species identification. Full article

The objective of the study was to determine the occurrence of Salmonella spp. infections in two Arctic fox (Alopex lagopus) farms in Poland, and to analyse the correlations between animals that tested positive for Salmonella spp and breeding results. Faecal samples were taken from 1094 clinically healthy blue foxes from the basic stock of farms A and B. Salmonella spp. were detected in 18.06% (56/310) of the samples collected in farm A and in 15.94% (125/784) of the samples collected in farm B. All isolated strains belonged to S. enterica subsp. enterica serotypes Salmonella Saintpaul (S. Saintpaul), Salmonella Reading (S. Reading), and Salmonella Heidelberg (S. Heidelberg). All three serotypes are typically isolated from commercial poultry flocks. Salmonella spp. infections significantly increased the risk of female infertility, but further research is needed to confirm the results. This is the first report on the prevalence of S. Heidelberg, S. Saintpaul, and S. Reading in faecal samples collected from Arctic fox (Alopex lagopus) farms in Poland. Full article