Background

Rabbit hemorrhagic disease (RHD) is an acute infectious disease that damages the rabbit industry by producing significant mortality rates in young and adult rabbits. RHD is better controlled by vaccination.

Objective

The current study's goal was to prepare and evaluate the immuno-enhancing effect of montanide ISA70 and aluminum hydroxide (Al(OH)₃) gel incorporated within the inactivated RHDV2 vaccine and assess the vaccine's protective efficacy against the homologous and heterologous local RHDV2 strains in rabbits.

Methods

Inactivated RHDV vaccines were prepared using Montanide ISA70 oil or Al(OH)₃ gel adjuvants and submitted to sterility, safety, and potency tests. 200 rabbits were equally divided into 4 groups: G1 (control), G2 (vaccinated with gel-incorporated vaccine), G3 (vaccinated with montanide-incorporated vaccine), and G4 (vaccinated with gel- and montanide-incorporated vaccines). Individual blood samples were collected from one week to six months from all groups. The vaccine's potency was measured by the HI test and protection percentage post challenge.

Results

Data revealed slightly increasing HI titer means reaching the 1st peak at 4 weeks post-vaccination (7.33, 7.67, and 7.33 log2 in the 2nd, 3rd, and 4th groups, respectively), then slightly decreasing and peaked again, giving 9.33 log2 for the2^nd group at 3 months post-vaccination (MPV), 10.67 log2 for 3rd the group, and 10.33 log2 for the 4th group at 5 months post-vaccination. Titer gradually decreased but remained protective. The protection rate ranged from 80–100% and 80–90% for homologous and heterologous local RHDV2 vaccines, respectively, within 3 weeks and 6 months post-challenge. The montanide oil RHDV2 vaccine induced better protection than the aluminum gel RHDV2 vaccine.

Conclusion

The results demonstrated evidence of cross-protection between RHDV2 strains. The oil emulsion vaccine induced higher and longer-lasting antibody titers than those obtained with the RHDV2 aluminum gel vaccine.

Background

Early diagnosis and treatment of anorectal atresia, a common congenital abnormality in calves, are crucial for preventing complications and ensuring the animal’s survival. Typically, newly born calves with this condition are present with an inability to defecate due to an absence of or an obstructed anal opening, often accompanied by abdominal pain and distension. History, physical examination, and radiographic imaging are frequently utilized diagnostic tools. This study aimed to evaluate the effectiveness of needle aspiration as a supportive diagnostic technique for anorectal atresia in bovine calves under field conditions and to assess its role in decision-making to proceed with surgical intervention.

Results

A total of 116 male calves, aged six hours to five days, were examined through clinical inspection, needle aspiration, and plain radiography. Clinical findings indicated that 62 cases had atresia ani, while 54 calves were diagnosed with atresia ani et recti. In cases without detectable swelling under the base of the tail, even with manually applied pressure on the abdomen, needle aspiration and radiographic findings showed positive results in 46.30% of calves. These cases were characterized by a radiolucent, distended rectal end close to the perineal skin surface (≤ 5 cm). Conversely, 53.70% of animals had negative aspiration results, with radiographic evidence of gas accumulation at the rectal end located > 5 cm from the perineal surface. Additionally, successful creation of an artificial anus at the perineum was achieved in cases with a rectal end near the skin surface. Whereas cases with a far rectal end more than 5 cm were subjected successfully to right flank laparo-typhlostomy.

Conclusions

Needle aspiration is a straightforward, non-invasive technique that proves highly valuable in facilitating diagnosis and guiding surgical decisions in calves with anorectal atresia, particularly in cases where bulging is not observed upon manual abdominal pressure. It is most effective when the rectal end is within five centimeters proximal to the perineal skin surface.

Recent advancements in wound care have explored the use of biological dressings, including fish skin, due to its rich collagen content and bioactive components that promote healing. This study aimed to evaluate the effectiveness of fresh and lyophilized Nile tilapia skin in enhancing full thickness skin wound healing in donkeys. Nile tilapia skin was collected, thoroughly washed, lyophilized, and sterilized. Five female donkeys were used in the study, each receiving three full-thickness skin wounds (2 cm x 2 cm) on each side of the back after aseptic preparation and local anesthesia, resulting in a total of six wounds per animal. The wounds were assigned to three groups: control (treated with saline), fresh fish skin, and lyophilized fish skin. Macroscopic wound assessment was performed and skin samples were collected on days 14 and 28 for histological examination using hematoxylin and eosin (H&E) and Crossman’s trichrome staining. Results revealed that treatment with lyophilized fish skin significantly accelerated wound contraction and epithelialization compared to the control and fresh fish skin-treated groups. On day 14, wound contraction rates were 43.57% ± 0.87 for lyophilized fish skin, 41.32% ± 0.26 for fresh fish skin, and 32.48% ± 0.39 for the control. By day 28, contraction rates increased to 74.37% ± 0.77, 66.92% ± 0.31, and 56.88% ± 0.73, respectively. Histological analysis showed enhanced collagen deposition and angiogenesis in the lyophilized fish skin group. In conclusion, lyophilized Nile tilapia skin is a promising and cost-effective biomaterial for enhancing wound healing, offering a practical solution for field veterinarians in low-resource settings.

Background

Delayed wound closure and non-healing wounds represent a problematic condition with health burden and an economic challenge. Therefore, different strategies have been developed, including skin tissue engineering, which aims to stimulate and support the wound healing process. In this study, the potential of graphene oxide (GO) and chitosan (CTS) biomaterial composite, with and without fetal bovine serum (FBS), was investigated to induce a full-thickness skin wound repair in rats.

Methods

The GO-CTS composite was characterized using X-ray diffraction, transmission electron microscopy, and Fourier transforms infrared. Cytocompatibility was evaluated via an MTT assay with human endothelial cells (ECs) and mouse embryonic fibroblasts (MEFs) in vitro. The in vivo wound regeneration potential was assessed by creating an 8 mm full-thickness circular skin defect on the dorsal surface of the rat. The defects were randomly divided into control, GO-CTS, FBS, and GO-CTS/FBS groups, and were monitored grossly and histologically at days 7 and 21 after wound induction.

Results

The GO-CTS material demonstrated high cytocompatibility, with cell viability recorded at 99.2% ± 5.7% for ECs and 110.5% ± 3.9% for MEFs. The highest proliferation rates were observed in the FBS (118.2% ± 2.1%) and GO-CTS/FBS (121.4% ± 4.4%) groups. In vivo, wound closure rates on day 21 were 85.5% ± 0.56% for GO-CTS, 87.5% ± 1.75% for FBS, and 91.5% ± 1.03% for GO-CTS/FBS, all significantly higher than the control group. Additionally, neovascularization, epithelialization, collagen deposition, and granulation tissue formation were more prominent in the treated groups, with skin appendages observed in the GO-CTS/FBS group.

Conclusion

GO-CTS nanosheets with FBS represent a promising biomaterial for skin tissue engineering and can effectively initiate and support wound healing.

Platelet-rich plasma (PRP) is an autologous concentration of platelets containing various growth factors that play a crucial role in tissue repair and regeneration. It has been widely investigated in various fields, including orthopedics, dentistry, and plastic surgery, for its potential to enhance healing processes. However, its efficacy in accelerating full-thickness skin wound healing remains a topic of ongoing research. This study aimed to evaluate the impact of PRP on wound closure in a rabbit model. Two full-thickness skin wounds (2-cm-diameter) were induced on the backs of 12 rabbits. Each animal received 0.5 ml of PRP on one wound, whereas the other wound served as a control. Wound healing was assessed grossly, morphometrically by digital imaging and histopathologically for 4 weeks. PRP significantly accelerated wound healing, with the PRP-treated group showing 58.17% closure by week 2 compared to 30.17% in controls. By week 4, both groups achieved near-complete closure (97.87% for PRP vs. 97.83% for control), but PRP demonstrated faster healing initially. Histopathological analysis at 2 weeks showed complete re-epithelialization and reduced inflammation in the PRP group, whereas the control group exhibited granulation tissue with infiltration of inflammatory cells and proliferation of fine capillaries (neo-vascularization). At 4 weeks of wound induction, the PRP-treated group showed increased epithelial coverage accompanied by hair follicle proliferation, while controls had an epithelial layer but no hair follicle proliferation. In conclusion, PRP significantly accelerates wound healing, particularly during the early phases, highlighting its potential in improving skin wound repair.

The occurrence of intra-abdominal adhesions after abdominal surgical interventions is considered an important issue in veterinary clinics. Although several adhesion-reducing agents were evoked to overcome the formation of such intra-abdominal adhesions, their effectiveness was still unsatisfactory. Hence, the present study assessed and compared the antiadhesive capability of gelatine and alginate sponges to minimize or prevent the formation of post-surgical intra-abdominal adhesions in a rabbit model. The cecal abrasion model was induced in animals and left untreated as control positive or treated with either intra-abdominal application of gelatine sponge (GS) or alginate sponge (AS). Clinical observation, gross appearance and histological evaluations were performed after 2 weeks of surgery. Grossly, the gelatine sponge enhanced the formation of intra-abdominal adhesions compared to the alginate sponge and control positive groups. Furthermore, both GS-treated and sham groups revealed no fibrosis on histological outcomes. The AS-treated group induced an extensive reaction with the formation of a marked degree of fibrosis and inflammatory cell infiltration. It was concluded that a gelatine sponge possesses the potential to prevent adhesions that could be formed intra-abdominally after abdominal surgery. An alginate sponge stimulates the formation of these adhesions.

A 6-month-old heifer cow was admitted to a Veterinary clinic in Bani-Ghaleb, Assiut, Egypt, with a large, nodular, vulvar, broad base tumor that had an outer necrosed, rough core and smaller blackish nodules at the thigh region. The animal displayed a normal appetite, and the clinical parameters were within the normal physiological limits. The tumor was resected surgically, thermocautarization was applied and the animal received supportive treatment and antibiotic therapy to get rid of secondary infections. The tumor was photographed and fixed in neutral buffer formalin 10% for further histopathological assessments that showed hyperkeratosis, koilocytosis, and acanthosis of the stratified squamous epithelium. Occasional eosinophilic intracytoplasmic inclusions were observed. Immunohistochemical results revealed nuclear immunopositivity to cellular proliferation markers (PCNA and Ki-67) of the stratum basale as well as fibroblasts. Vimentin-positive labeling was remarkable in the dermal connective tissue. Myofibroblasts, smooth muscles of hair follicles, and dilated capillaries showed α-SMA positive reaction. Tumor recurrence didn’t occur during a period of follow-up that extended to six months. We concluded that surgical excision with thermocautarization is the ideal treatment for genital fibropapillomas. Since the animal was sexually immature, genital papillomas are not restricted to venereal transmission. Further hormonal immunoassays are recommended.

Meniscal tears in the inner avascular area have been reported as a common cause of disability in dogs that associated with failure of healing process due to their limited vascularity. In spite of various sterategies were reported for treatment of such tears, their clinical use was limited. Therefore, different biomaterials have been assessed to stimulate regeneration of avascular meniscal tears. Currently, silver nanoparticles (AgNPs) enormously involved in biomedicine including tissue regeneration, drug delivary, and antibacterial applications. Thus, AgNPs was fabricated in the present study to investigate its potential to induce and support meniscal healing process in an avascular meniscal tear model. The nanomaterial was synthesized and characterized using transmission electron microscope (TEM). Next, a full thickness longitudinal meniscal tear was created in the avascular zone and either left empty or treated with AgNPs.  Animals were monitored clinically at weeks 3, 6, 9, and 12 weeks after surgery for lameness parameters including lameness during walking, pain on manipulation, range of motion, and functional disability. Additionally, the harvested menisci were examined macroscopically and histologically at 4, 8, and 12 weeks. The designed material revealed improved clinical outcomes compared to control group. The gross and histological observations proved that the meniscal healing was stimulated in the AgNPs-treated group in comparison to control one, where the AgNPs-treated tear sites were filled with reparative tissue. In conclusion, AgNPs nanomaterial has a promoting effect on the process of meniscal tissue healing in the avascular region, proving that AgNPs is a promising material for meniscal tissue regeneration.

Repair of meniscal tears in the avascular zone represents an obstacle for orthopedic surgeons. Several therapeutic methods have been suggested to mange these tears including meniscectomy and meniscal allografts; however, their clinical application was restricted due to their disadvantages. These limitations inspired the necessity to develop products that possess the ability to initiate healing in such avascular tears. Hence, the goal of the current study is to assess and compare the regenerative capability of bone marrow aspirate (BMA) and platelet-rich plasma (PRP) to enhance repair of avascular meniscal tears. After preparation of BMA and PRP, meniscal tear was conducted in the inner avascular zones in dogs and left untreated as control or treated with either BMA or PRP. Clinical observation of weight bearing, lameness, pain on manipulation, gait, and functional disability were investigated after 3, 6, 9, and 12 weeks of surgery. In addition, gross and histological evaluations were performed at weeks 4, 8, and 12 after surgery. Both materials demonstrated a positive improvement in clinical observations compared to the control group. Furthermore, repair of meniscal tears was stimulated in tears treated with either BMA or PRP with better gross and histological outcomes in PRP-treated group than BMA-treated group. To conclude, our findings showed that BMA and PRP possess the potential to enhance the healing process of meniscal tears in the inner avascular region with the superiority of PRP.

Niosomes are promising nanocarriers for ocular drug administration since they have the potential to enhance the bioavailability and efficacy of different drugs. Meanwhile, topical gels are beneficial for the treatment of ocular inflammation as they improve corneal permeability and increase the contact time with the eye surface. The main purpose of this study was to prepare and evaluate novel niosomal gels for intraocular delivery of celecoxib. Different niosomes were prepared using different surfactants (span 60 and span 40) and cholesterol (30-50 mol %). The optimized formulation made with span 40 and cholesterol (7:3 molar ratio) has a relatively high encapsulation efficiency (~57%) with reasonable particle size for ocular delivery (~348 nm) and showed the highest release of ~65% after 24 hrs compared to other formulations. The optimized niosomal formulation was then used to prepare various formulations of celecoxib in-situ gel and topical hydrogels. The niosomal gels were well tolerated by the eye and showed similar celecoxib corneal permeation. However, the in-situ gel showed a higher anti-inflammatory effect compared to the topical hydrogel and a commercially available diclofenac eye drop. The results shown in this study indicate that celecoxib niosomal in-situ gel is a valuable drug delivery system for ocular inflammation.