Tryptophan intrinsic fluorescence from wound healing correlates with re-epithelialization in a rabbit model.

BACKGROUND: Wound healing monitoring and timely decision-making are critical for wound classification. Tryptophan (Tr) intrinsic fluorescence, detected at 295/340 nm, provides a noninvasive approach for wound assessment. Our previous work demonstrated that this autofluorescence is associated with keratinocytes in a highly proliferative state in vitro. OBJECTIVE: We investigated the correlation between Tr fluorescence and key wound healing parameters, including re-epithelialization, fibrosis, neovascularization, and acute and chronic inflammation, using a rabbit model. METHODS: Seven rabbits underwent wound healing assessment over a 15-day period. We employed histological analysis from central and marginal biopsies, and UV fluorescence imaging captured by a monochromatic near-UV sensitive camera equipped with a passband optical filter (340 nm/12 nm). Excitation was achieved using a 295 nm LEDs ring lamp. Normalized fluorescence values were correlated with histological measurements using Pearson correlation. RESULTS: The UV fluorescence strongly exhibited a strong correlation with re-epithelization (r = 0.8) at the wound edge, with peak intensity observed between the sixth and ninth days. Notably, wound-healing dynamics differed between the wound center and edge, primarily attributed to variations in re-epithelialization, neovascularization, and chronic inflammation. CONCLUSION: Our findings highlight the presence of autofluorescence at 295/340 nm during wound healing, demonstrating a robust association with re-epithelialization. This excitation/emission signal holds promise as a valuable noninvasive strategy for monitoring wound closure, re-epithelialization, and other biological processes where Tr plays a pivotal role.

Physicochemical Characterization of Yogurt Fortified with Microencapsulated Cinnamon (Cinnamomum zeylanicum) and Its Effects on Metabolic Syndrome Induced in Rabbits (Oryctolagus cuniculus).

Chronic noncommunicable diseases are a global health problem causing increased rates of mortality and sick leaves, which can be reduced by controlling dyslipidemia and hyperglycemia. Experimental and clinical studies have demonstrated the antidiabetic, lipid-lowering, antiobesogenic, anti-inflammatory, and antihypertensive properties of cinnamon; therefore, its use in yogurt can help reverse the effects of these diseases. Our study aims to evaluate the effect of a microencapsulated aqueous extract of cinnamon (Cinnamomum zeylanicum) (MCE Cz) incorporated in a yogurt drink on metabolic syndrome (MS) in a rabbit (Oryctolagus cuniculus). Physicochemical, microbiological, and proximal chemical characterization; total phenol, flavonoid, and 2,2-diphenyl-1-picrylhydrazil activity quantification; intestinal bioaccessibility; sensory analysis; MS induction through diet; and treatment with 5, 10, and 20 mg/kg of flavonoids contained in the MCE Cz were performed to help evaluate morphological, biochemical, and lipid peroxidation measurements in the liver and heart. The results show that the addition of MCE Cz in the yogurt modified the yogurt texture, increased its adhesiveness and firmness, and imparted a characteristic cinnamon color and biological value by providing intestinally bioaccessible antioxidants with antioxidant potential by reducing lipoperoxidation in the liver and heart after treatment. MCE Cz reduced the weight of the animals by up to 38.5% and the abdominal circumference by 29%. Biochemically, it decreased glucose levels by 24.38%, total cholesterol levels by 69.2%, triglyceride levels by 72.69%, and low-density lipoprotein levels by 89.25%; it increased high-density lipoprotein levels by 67.08%. Therefore, adding MCE Cz in doses of 5 and 10 mg of flavonoids in drinkable yogurt can be an alternative to preparing functional foods with physicochemical attributes and biological properties that can be consumed at all stages of life without undesirable effects. Moreover, it can act as a potential adjuvant in the treatment of comorbidities related to MS.

Early detection of optic nerve head changes using optical coherence tomography after using mesenchymal stromal cells as intravitreal therapy in rabbit models of ocular hypertension.

Background and Aim: Stem cell therapy is considered a promising treatment for several neurodegenerative diseases. However, there are very few studies on the use of this therapy in glaucoma models. By detecting the changes produced by glaucoma early, cell therapy could help prevent the events that lead to blindness. In this study, early changes in the optic nerve head (ONH) as detected by optical coherence tomography (OCT) after the application of human Wharton's jelly-derived mesenchymal stromal cells (hWJ-MSCs) in an experimental model of ocular hypertension (OH) were evaluated. Materials and Methods: Fifteen New Zealand rabbits were randomly divided into the following three groups: G1: OH, G2: hWJ-MSCs, and G3: OH + hWJ-MSCs. An OH model was constructed, and the intraocular pressure (IOP) was measured regularly. At week 7, 105/100 µL hWJ-MSCs were intravitreally injected. Retinography and OCT were used to evaluate structural changes in ONH. Results: IOP increased significantly in G1 and G3 from week 3 onward. Retinography revealed more significant optic nerve changes, that is, papillary asymmetry suggestive of optic nerve excavation, vascular alterations, and irregular hypopigmentation peripheral to the optic disk margin, in G1 compared with G3. OH locates the hWJ-MSCs solution in the vitreous in front of the optic nerve. OCT revealed retinal nerve fiber layer (RNFL) reduction in all groups, reduced optic cup volume in G2 and G3 between weeks 1 and 9, and significant ganglion cell layer thickness reduction in G1 and a slight increase in G3. Conclusion: Intravitreal hWJ-MSCs injection produced changes in optic cup volume, which were detected early on by OCT; however, RNFL could not be restored in this OH model.

K-wire is more damaging than standard or acrylic drill bits when evaluating torsional properties of rabbit (Oryctolagus cuniculi) femurs.

OBJECTIVE: The objective of this study is to compare drilling variables and torsional mechanical properties of rabbit femora after bicortical drilling with a 1.5-mm standard surgical drill bit, acrylic drill bit, and K-wire. SAMPLES: 24 pairs of rabbit femora. METHODS: After drilling under controlled axial displacement rate, each bone was biaxially loaded in compression followed by rapid external torsion to failure. Maximum axial thrust force, maximum drill torque, integral of force and displacement, change in temperature, maximum power spectral density of the torque signal, torque vibration, and torque and angle at the yield and failure points were collected. Pre- and postyield stiffness, yield and failure energies, and postyield energy were calculated. RESULTS: The work required to drill through the cis- and transcortices (integral of force and displacement) was greater for the K-wire, followed by the acrylic and then standard drill bits, respectively. The K-wire demonstrated higher maximum torque than the drill bits at the ciscortex, and the force of drilling was significantly greater. The vibration data was greater with the acrylic and standard drill bits than the K-wire. There was no difference in torsional strength between drilling types. CLINICAL RELEVANCE: Mechanical differences exist between different drill bits and K-wire and demonstrate that the K-wire is overall more damaging than the surgical drill bit.

First Detection of Benign Rabbit Caliciviruses in Chile.

Pathogenic lagoviruses (Rabbit hemorrhagic disease virus, RHDV) are widely spread across the world and are used in Australia and New Zealand to control populations of feral European rabbits. The spread of the non-pathogenic lagoviruses, e.g., rabbit calicivirus (RCV), is less well studied as the infection results in no clinical signs. Nonetheless, RCV has important implications for the spread of RHDV and rabbit biocontrol as it can provide varying levels of cross-protection against fatal infection with pathogenic lagoviruses. In Chile, where European rabbits are also an introduced species, myxoma virus was used for localised biocontrol of rabbits in the 1950s. To date, there have been no studies investigating the presence of lagoviruses in the Chilean feral rabbit population. In this study, liver and duodenum rabbit samples from central Chile were tested for the presence of lagoviruses and positive samples were subject to whole RNA sequencing and subsequent data analysis. Phylogenetic analysis revealed a novel RCV variant in duodenal samples that likely originated from European RCVs. Sequencing analysis also detected the presence of a rabbit astrovirus in one of the lagovirus-positive samples.

Experimental Lab Tests on Rabbits for the Optimization and Redesign of Low-Cost Equipment for Automated Peritoneal Dialysis.

This work shows the experiences acquired by the experimental test performed to validate an automated peritoneal dialysis machine using rabbits with kidney damage to find improvements that can be made for future advances. These are listed to understand the direction of the development of the machine. The article shows the device's background and previous tests using a testbed. The rabbit anatomy was prepared for nephrectomy surgery. The tests were practiced by checking all of the APD machine's subsystems. The data were analyzed to develop improvements in the process. The results indicate the importance of the DPA machine as an alternative by implementing peristaltic pumps to substitute disposable cassettes. The identified improvements are the main objectives for research to continue improving the technology.

Rabbit Fibroma Virus infection in domestic rabbits (Oryctolagus cuniculus) in Mexico.

Rabbit Fibroma is a Leporipoxviral disease and is considered the third most common cutaneous neoplasm in pet rabbits. Two domestic rabbits (Oryctolagus cuniculus) were submitted to the veterinary clinic due to the presence of a nodule on the lip. Histologically, epithelial cells of the epidermis and hair follicles showed mild to moderate ballooning degeneration, spongiosis, and several eosinophilic intracytoplasmic inclusion bodies. The dermis was expanded by atypical spindle cells that also showed eosinophilic intracytoplasmic inclusion bodies. The tissues were evaluated by using transmission electron microscopy. In both cases, keratinocytes exhibit several electron dense and pleomorphic intracytoplasmic viral particles consistent with Poxviruses. To our knowledge, this is the first case report of Rabbit Fibroma Virus infection in Domestic Rabbits in Mexico.

Effects of replacement of dietary fish oil with plant oil on growth performance and fatty acid composition of spinefoot rabbitfish, Siganus rivulatus

A 95-day feeding study was carried out to evaluate the impact of complete replacement of fish oil by plant oils in the growth performance, feed consumption fatty acid and body composition of juvenile rabbitfish, Siganus rivulatus. There were four treatments i.e., A (fish oil diet), (linseed oil diet), C (soybean meal oil diet) and D (sunflower oil diet). The experimental trial was conducted in twelve 1.5-m3 fiber glass tanks (n=3). Spinefoot rabbitfish juveniles had an average initial weight of 0.948 g ± 0.124 g and they were stocked at 50 fish per tank. Fish fed diet A showed significantly better growth rate, final body weight, and total body weight than fish fed on the other diets. Moreover, the best FCR was observed for diet A followed by diet C and diets B and D had the worst FCR. Fish body composition for crude protein, dry matter, ashes and gross energy at the end of the trial had not differed between the treatments. The highest polyunsaturated fatty acids (PUFA) was found in fish fed diet A followed in decreasing order by diets D, B, and C. Fish oil is a better dietary lipid source for Spinefoot rabbitfish juveniles, Siganus rivulatus, than plant oils. Among plant oils, soybean oil was better than linseed oil and sunflower oil as the main dietary fat source.

Um estudo de alimentação de 95 dias foi realizado para avaliar o impacto da substituição completa de óleo de peixe por óleos vegetais no desempenho de crescimento, composição corporal e consumo de ração de juvenis de coelho, Siganus rivulatus. Houve quatro tratamentos, ou seja, A (dieta de óleo de peixe), (dieta de óleo de linhaça), C (dieta de óleo de farelo de soja) e D (dieta de óleo de girassol). O ensaio experimental foi conduzido em doze tanques de fibra de vidro de 1,5 m3 (n=3). Os juvenis de peixe-coelho-de-espinho apresentaram peso inicial médio de 0,948 g ± 0,124 g e foram estocados com 50 peixes por tanque. Os peixes alimentados com a dieta A apresentaram taxa de crescimento, peso corporal final e peso corporal total significativamente melhores do que os peixes alimentados com as outras dietas. Além disso, a melhor CAA foi observada para a dieta A seguida da dieta C e as dietas B e D tiveram a pior CA. A composição corporal dos peixes para proteína bruta, matéria seca, cinzas e energia bruta ao final do experimento não diferiu entre os tratamentos. O maior teor de ácidos graxos poliinsaturados (PUFA) foi encontrado nos peixes alimentados com a dieta A seguido em ordem decrescente pelas dietas D, B e C. O óleo de peixe é uma melhor fonte de lipídios dietéticos para juvenis de peixe-coelho, Siganus rivulatus, do que os óleos vegetais. Entre os óleos vegetais, o óleo de soja foi melhor que o óleo de linhaça e o óleo de girassol como principal fonte de gordura da dieta.

Evaluation of a prepared combined inactivated vaccine against hemorrhagic disease virus 2 and Clostridium perfringens type A infections in rabbit

Rabbit hemorrhagic disease virus 2 and Clostridium perfringens type A cause infections in rabbit. Vaccines are considered an effective strategy for fighting these infections. Nowadays, the demand for using a nanoparticle adjuvant as (Montanide IMS) is increased due to its ability for enhancing both humoral and cell mediated immunity and, in addition, it can be administrated through different routes. An inactivated vaccine against rabbit hemorrhagic disease virus 2 and Clostridium perfringens type A which adjuvanted by Montanide; IMS 1313 N VG PR (IMS 1313) was developed. The prepared vaccine was evaluated in rabbits for sterility, safety and potency via two different routes of vaccination. Oral administration of inactivated vaccine was evaluated as an alternative route to subcutaneous vaccination. The results revealed that rabbits vaccinated by subcutaneous route exhibited satisfactory antibody and antitoxin titer against rabbit hemorrhagic disease virus 2 and Clostridium perfringens type A, respectively, from 2nd week post vaccination and reached the peak at 3th week post vaccination. On the other hand, antibody and antitoxin titer of orally vaccinated rabbits didn't reach the satisfactory level. Rabbits vaccinated orally were not protected against virulent rabbit hemorrhagic disease virus 2, with 30percent protection, while rabbits vaccinated subcutaneously showed satisfactory protection (90percent). Serum nitric oxide and lysozyme activity had significant differences between vaccinated and control rabbits. The level of nitric oxide and lysozyme in sera of subcutaneously vaccinated rabbits was higher than that of orally vaccinated rabbits. Interleukin-6 and tumor necrosis factor-ɑ were determined in the spleen of vaccinated rabbits, significant differences were obtained between subcutaneously and orally vaccinated rabbits. It was concluded that the combined vaccine is potent when inoculated by subcutaneous route in contrast to the oral route. The Montanide; IMS 1313 adjuvant is a product that can be used for rabbit vaccine preparation(AU)

El virus de la enfermedad hemorrágica del conejo tipo 2 y el Clostridium perfringens tipo A causan infecciones en conejos. Las vacunas se consideran una estrategia eficaz para combatir estas infecciones. Hoy en día, la demanda para el uso de un adyuvante de nanopartículas como Montanide; IMS es cada vez mayor debido a su capacidad para mejorar la inmunidad humoral y la mediada por células, y a la posibilidad de administrarla por diferentes vías. En este estudio se desarrolló una vacuna inactivada contra el virus de la enfermedad hemorrágica del conejo tipo 2 y el Clostridium perfringens tipo A, adyuvada con Montanide™ IMS 1313 N VG PR (IMS 1313). Se evaluó la vacuna preparada en cuanto a esterilidad, seguridad y potencia en conejos mediante dos vías diferentes de vacunación. Se evaluó la administración oral de la vacuna inactivada como vía alternativa a la vacunación subcutánea. Los resultados revelaron que los conejos vacunados por vía subcutánea presentaban títulos satisfactorios de anticuerpos y antitoxinas contra el virus 2 de la enfermedad hemorrágica del conejo y el Clostridium perfringens tipo A, respectivamente, a partir de la segunda semana de vacunación y alcanzaron el máximo en la tercera semana. En cambio, los títulos de anticuerpos y antitoxinas de los conejos vacunados por vía oral no alcanzaron un nivel satisfactorio. Los conejos vacunados por vía oral no mostraron protección contra el virus virulento de la enfermedad hemorrágica del conejo tipo 2, con un 30 por ciento de protección, mientras que los conejos vacunados por vía subcutánea mostraron una protección satisfactoria (90 por ciento). El óxido nítrico sérico y la actividad de la lisozima presentaron diferencias significativas entre los conejos vacunados y los controles. El nivel de óxido nítrico y lisozima en el suero de los conejos vacunados por vía subcutánea fue superior al de los conejos vacunados por vía oral. Se determinaron la interleucina-6 y el factor de necrosis tumoral; en el bazo de los conejos vacunados, y se obtuvieron diferencias significativas entre los conejos vacunados por la vía subcutánea y la oral. Se concluyó que la vacuna combinada es potente cuando se inocula por vía subcutánea en contraste con la vía oral. El adyuvante Montanide; IMS 1313 es un producto que puede utilizarse para la preparación de vacunas para conejos(AU)

Modeling Paratuberculosis in Laboratory Animals, Cells, or Tissues: A Focus on Their Applications for Pathogenesis, Diagnosis, Vaccines, and Therapy Studies.

Paratuberculosis is a chronic granulomatous enteritis caused by Mycobacterium avium subsp. Paratuberculosis that affects a wide variety of domestic and wild animals. It is considered one of the diseases with the highest economic impact on the ruminant industry. Despite many efforts and intensive research, paratuberculosis control still remains controversial, and the existing diagnostic and immunoprophylactic tools have great limitations. Thus, models play a crucial role in understanding the pathogenesis of infection and disease, and in testing novel vaccine candidates. Ruminant animal models can be restricted by several reasons, related to space requirements, the cost of the animals, and the maintenance of the facilities. Therefore, we review the potential and limitations of the different experimental approaches currently used in paratuberculosis research, focusing on laboratory animals and cell-based models. The aim of this review is to offer a vision of the models that have been used, and what has been achieved or discovered with each one, so that the reader can choose the best model to answer their scientific questions and prove their hypotheses. Also, we bring forward new approaches that we consider worth exploring in the near future.

Rabbits as Animal Models for Anti-Tick Vaccine Development: A Global Scenario.

Studies evaluating candidate tick-derived proteins as anti-tick vaccines in natural hosts have been limited due to high costs. To overcome this problem, animal models are used in immunization tests. The aim of this article was to review the use of rabbits as an experimental model for the evaluation of tick-derived proteins as vaccines. A total of 57 tick proteins were tested for their immunogenic potential using rabbits as models for vaccination. The most commonly used rabbit breeds were New Zealand (73.8%), Japanese white (19%), Californians (4.8%) and Flemish lop-eared (2.4%) rabbits. Anti-tick vaccines efficacy resulted in up to 99.9%. Haemaphysalis longicornis (17.9%) and Ornithodoros moubata (12.8%) were the most common tick models in vaccination trials. Experiments with rabbits have revealed that some proteins (CoAQP, OeAQP, OeAQP1, Bm86, GST-Hl, 64TRP, serpins and voraxin) can induce immune responses against various tick species. In addition, in some cases it was possible to determine that the vaccine efficacy in rabbits was similar to that of experiments performed on natural hosts (e.g., Bm86, IrFER2, RmFER2, serpins and serine protease inhibitor). In conclusion, results showed that prior to performing anti-tick vaccination trials using natural hosts, rabbits can be used as suitable experimental models for these studies.

Rickettsial antibodies and Rickettsia bellii detection in lagomorphs and their ectoparasites in Northern Baja California, Mexico.

Lagomorphs-principally rabbits and hares-have been implicated as hosts for vectors and reservoirs for pathogens associated with multiple rickettsial diseases. Western North America is home to diverse rickettsial pathogens which circulate among multiple wild and domestic hosts and tick and flea vectors. The purpose of this study was to assess lagomorphs and their ectoparasites in 2 locations in northern Baja California, Mexico, for exposure to and infection with rickettsial organisms. In total, 55 desert cottontail rabbits (Sylvilagus audubonii) (Baird) and 2 black-tailed jackrabbits (Lepus californicus) (Gray) were captured. In Mexicali, ticks were collected from 44% (14/32) of individuals, and were exclusively Haemaphysalis leporispalustrisNeumann (Acari: Ixodidae); in Ensenada, ticks were collected from 70% (16/23) individuals, and 95% were Dermacentor parumapertus. Euhoplopsyllus glacialis affinisBaker (Siphonaptera: Pulicidae) fleas were collected from 72% of rabbits and 1 jackrabbit from Mexicali, while the few fleas found on hosts in Ensenada were Echidnophaga gallinaceaWestwood (Siphonaptera: Pulicidae) and Cediopsylla inaequalis(Siphonaptera: Pulicidae). Rickettsia bellii was the only rickettsial organism detected and was identified in 88% of D. parumapertus and 67% of H. leporispalustris ticks from Ensenada. A single tissue sample from a jackrabbit was positive for R. belli (Rickettsiales: Rickettsiaceae). Hosts in Ensenada had a significantly higher prevalence of rickettsial antibodies than hosts in Mexicali (52.3% vs. 21.4%). Although R. bellii is not regarded as pathogenic in humans or other mammals, it may contribute to immunity to other rickettsiae. The marked difference in distribution of ticks, fleas, and rickettsial exposure between the 2 locations suggests that disease transmission risk may vary markedly between communities within the same region.

Effect of sulforaphane on long-term storage of rabbit semen.

In this study, it was aimed to determine the effect of sulforaphane (SFN) on rabbit semen cryopreservation. Semen collected from animals was divided into 5 equal volumes as Control, SFN 5 µM, SFN 10 µM, SFN 25 µM and SFN 50 µM groups. Afterwards, semen analyzes were performed. According to our results, there was no statistical difference between the groups at 4°C. However after freezing thawing, the highest total motility, progressive motility and rapid spermatozoa rate was seen in the 10 µM SFN group, while the lowest was observed in the 50 µM SFN group (P<0.05). Static sperm ratio was highest in the 50 µM group, while the lowest was observed in the 10 µM SFN group. When flow cytometry results examined the rate of acrosomal damaged and dead sperm was the lowest in the 10 µM SFN group, a statistical difference was observed between the control group (P<0.05). The highest rate of sperm with high mitochondrial membrane potential was seen in the 5 µM SFN and 10 µM SFN groups. Apoptosis and ROS rates were found to be lower in the experimental groups compared to the control groups (P<0.05). As a result, SFN supplementation at a dose of 10 µM increased the quality of sperm in the freezing and thawing processes of rabbit semen. In conclusion, 10 µM SFN improved the quality of cryopreservation of rabbit semen.

Evaluation of Two Configurations of Hydroxyapatite and Beta-Tricalcium Phosphate in Sinus Grafts with Simultaneous Implant Installation: An Experimental Study in Rabbits.

BACKGROUND: This study aimed to evaluate peri-implant bone formation in rabbits after sinus grafting mediated by hydroxyapatite and beta-tricalcium phosphate (HA + ß-TCP) in granule or paste configurations, concomitant with immediate implant installation. MATERIAL & METHODS: Thirty-four rabbit maxillary sinuses were grafted with HA + ß-TCP, half of which were applied in a granule and half in a paste composition. Implant placement was performed simultaneously. At 7 and 40 days postoperatively, the animals were euthanized, and samples were prepared for tomographic, microtomographic, histological, histometric (hematoxylin and eosin staining, HE), and immunohistochemical (labeling of transcription factor Runx-2 [RUNX2], vascular endothelial growth factor [VEGF], osteocalcin [OCN], and tartrate-resistant acid phosphatase [TRAP]) analysis. Implant removal torque was also measured. RESULTS: On tomography, maintenance of sinus membrane integrity was observed in both the groups. Higher values of morphometric parameters evaluated by micro-CT were found in the "paste group" after seven days. At 40 days, there were no significant differences between the groups in most of the microtomographic parameters evaluated. In histological sections stained with HE, a higher percentage of newly formed bone was observed in the "granule group" after 40 days. Similar positive immunolabeling was observed for both RUNX2 and OCN in both the experimental groups. TRAP immunolabeling was similar in both groups as well. VEGF labeling increased in the "granule group", indicating a higher osteoconductive potential in this biomaterial. Similar removal torque values were observed in both groups. Thus, the two HA + ß-TCP configurations showed similar healing patterns of simultaneously installed implants adjacent to sinus floor elevation. However, significantly higher bone values were observed for the "granule configuration". CONCLUSIONS: The HA + ß-TCP granules and paste presentations showed favorable long-term healing results, with bone formation in similar quantities and quality adjacent to the implants.

Ligamentum teres reconstruction using autogenous semitendinosus tendon with toggle technique in rabbits.

Background: Ligamentum teres (LT) has traditionally been considered a vestigial or redundant structure in humans; however, based on new studies and the evolution of hip arthroscopy, the LT injury has been viewed as a source of hip pain. Therefore, LT reconstruction can be beneficial in some cases. Rabbits have been frequently used as a model for cranial cruciate ligament reconstruction but few studies are available for ligamentum teres reconstruction. Objective: To evaluate the semitendinosus tendon to replace ligamentum teres with the toggle technique, using rabbits as an experimental model. Methods: Twenty-six female Norfolk rabbits with approximately 3 months of age were divided into two equal groups after excision of ligamentum teres (LT) from the right hip joint: G1-no reconstruction of LT and capsulorrhaphy; G2-double-bundle reconstruction of the LT using semitendinosus tendon autograft. In both groups, the LT was removed from the right hip joint. In G2 the autograft was harvested from the left hind limb of the same rabbit. The rabbits were evaluated clinically at different time intervals; before surgery (M1), 48 h (M2), 15 days (M3), 30 days (M4) and 90 days (M5) after surgery. Results: The rabbits supported their limbs on the ground in both the groups. As complications of the procedure, four hip joints showed subluxations in the radiographic evaluation of G1; three at M4 and one at M5. In G2; two luxations of hip joints at M3 and one subluxation at M4 were seen. On ultrasound, irregular articular surface was seen in 30.8% of the rabbits that had subluxation of hip joints. Gross evaluation identified tendon graft integrity in 76.92% of the rabbits. Histological analysis revealed graft adhesion to the bone in the early phase comprised of sharpey-like collagen fibers. Conclusion: The double-bundle reconstruction of the LT using autologous semitendinosus tendon associated with the toggle rod shows an early phase of tendon graft ligamentization at 90 days post-operatively in young rabbits, but biomechanical bias suffered by the tendon during gait must be considered.

Oxytocin antagonist does not disrupt rabbit maternal behavior despite binding to brain oxytocin receptors.

We explored a possible role of oxytocin (OXT) for the onset and maintenance of rabbit maternal behavior by: (a) confirming that a selective oxytocin receptor antagonist (OTA) widely used in rodents selectively binds to OXT receptors (OXTR) in the rabbit brain and (b) determining the effect of daily intracerebroventricular (icv) injections of OTA to primiparous and multiparous does from gestation day 29 to lactation day 3. OTA efficiently displaced the high affinity, selective oxytocin receptor (OXTR) radioligand, 125 I-labeled ornithine vasotocin analog (125 I-OVTA), but was much less effective at displacing the selective V1a vasopressin receptor radioligand, 125 I-labeled linear vasopressin, thus showing high affinity and selectivity of OTA for rabbit OXTR as in rodents. Further, ICV OTA injections did not modify nest-building, latency to enter the nest box, time spent nursing or the amount of milk produced, relative to vehicle-injected does. The percentage of mothers suckling the litter was also similar between both groups, regardless of parity. Together, our results do not support a role of OXT for the initiation or maintenance of rabbit maternal behavior. Future studies are warranted to determine if OXT participates in fine-tuning additional aspects of the maternal ethogram, for example, circadian periodicity of nursing and nest defense.

Microplastic abundance in feces of lagomorphs in relation to urbanization.

The presence of microplastics (MPs) in marine environments has been extensively documented. However, studies of terrestrial species are scarce. Fecal samples (105) of lagomorphs were collected at sites with different levels of urbanization in the Baja California Chaparral and analyzed to quantify and characterize MPs found in the feces. The lagomorph species recorded in the study area are the desert cottontail rabbit (Sylvilagus audubonii), brush rabbit (Sylvilagus bachmani), and black-tailed jackrabbit (Lepus californicus), which play important roles in the food web of the chaparral ecosystem. Microplastics were identified using attenuated total reflectance Fourier transform infrared spectroscopy. Microplastics were detected in 49 % of the samples, with fibers being the dominant shape found (72 %). Most (75 %) of the MPs were <1 mm in size, with a mean length of 0.93 ± 0.99 mm (median 0.60 mm, range 0.02 - <5 mm). Polyamide was the dominant polymer (54 %), indicating that MPs are likely derived from textiles; polyethylene was also abundant (27 %). A difference was also observed in the abundance of MPs in feces from sites with different levels of urbanization, with the highest abundance in feces from the urban sites.

Technological performance of different rabbit meat cuts in processing cured cooked ready-to-eat meat products / Desempenho tecnológico de cortes diferentes de carne de coelho no processamento de produtos cárneos curados cozidos prontos para consumo

There is a worldwide demand for new protein sources through environmentally responsible production, and rabbit farming is a sustainable activity. Therefore, this study aimed to characterize meat from different cuts of rabbit carcasses and evaluate their use in the processing of restructured cured cooked ready-to-eat (RTE) products. Rabbit raw meats from different cuts were technologically characterized, and the RTE products were processed from the meats of the entire carcass (RABB), hind legs (RHIND), loin (RLOIN), and foreleg, thoracic cage, and flank (RBACK). Restructured pork cooked ham (PHAM) was used as the reference. Rabbit raw meat from different anatomical parts differed in proximate composition, total collagen and heme-pigment content, water-holding capacity, and CIE color, affecting the characteristics of processed products. RBACK products had higher fat content (5.46%), cooking and reheating losses (7.50% and 5.61%), and poor hardness and chewiness (11.1 N and 17.37 N×mm). Higher values of lightness (L* ~70.27), hue (h ~68.61°), and a slight cured color were observed in RLOIN, with a pale yellowish color described by sensory evaluation. RABB and RHIND were correlated with the sensory attributes of traditional PHAM, being preferred more often and with greater purchase intent than RLOIN and RBACK. It is concluded that cooked ham development from whole carcass meat (RABB) is a potential opportunity for the rabbit industry to offer value-added technological products of high quality to consumers.

Há uma demanda mundial por novas fontes proteicas de produções ambientalmente responsáveis, e a cunicultura se enquadra perfeitamente como uma atividade sustentável. Neste contexto, este estudo teve como objetivo caracterizar a carne de diferentes cortes da carcaça de coelho e avaliar sua utilização no processamento de produtos curados cozidos prontos para o consumo (RTE). As carnes cruas de coelho de diferentes cortes foram caracterizadas tecnologicamente, e os produtos RTE foram processados a partir das carnes de carcaça inteira (FC-INT), patas traseiras (FC-PERNIL), lombo (FCLOMBO), patas dianteiras, caixa torácica e flanco (FC-APARAS). Um produto RTE com carne de pernil suíno (APRESUNTADO) também foi elaborado como referência. A carne de coelho de diferentes partes anatômicas diferiu na composição centesimal, conteúdo total de colágeno e pigmento heme, capacidade de retenção de água e cor (CIE), afetando as características dos produtos elaborados. Os produtos FC-APARAS apresentaram maior teor de gordura (5.46%), perdas por cozimento e reaquecimento (7,50% e 5,61%), baixa dureza e mastigabilidade (11.1 N e 17.37 N×mm). Maiores valores de luminosidade (L* ~70.27), matiz (h ~68.61°) de cor e uma fraca cor curada foram observados no FC-LOMBO, com uma coloração amarelada pálida descrita pela avaliação sensorial. FC-INT e FC-PERNIL foram correlacionados com os atributos sensoriais do tradicional APRESUNTADO, sendo mais preferidos e com maior intenção de compra do que FCLOMBO e FC-APARAS. Concluiu-se que o desenvolvimento de produtos curados cozidos a partir de carcaças inteiras (FC-INT) é uma oportunidade potencial para a indústria de cunicultura oferecer produtos tecnológicos de valor agregado e de alta qualidade aos consumidores.

Effect of sulforaphane on long-term storage of rabbit semen

In this study, it was aimed to determine the effect of sulforaphane (SFN) on rabbit semen cryopreservation. Semen collected from animals was divided into 5 equal volumes as Control, SFN 5 µM, SFN 10 µM, SFN 25 µM and SFN 50 µM groups. Afterwards, semen analyzes were performed. According to our results, there was no statistical difference between the groups at 4°C. However after freezing thawing, the highest total motility, progressive motility and rapid spermatozoa rate was seen in the 10 µM SFN group, while the lowest was observed in the 50 µM SFN group (P<0.05). Static sperm ratio was highest in the 50 µM group, while the lowest was observed in the 10 µM SFN group. When flow cytometry results examined the rate of acrosomal damaged and dead sperm was the lowest in the 10 µM SFN group, a statistical difference was observed between the control group (P<0.05). The highest rate of sperm with high mitochondrial membrane potential was seen in the 5 µM SFN and 10 µM SFN groups. Apoptosis and ROS rates were found to be lower in the experimental groups compared to the control groups (P<0.05). As a result, SFN supplementation at a dose of 10 µM increased the quality of sperm in the freezing and thawing processes of rabbit semen. In conclusion, 10 µM SFN improved the quality of cryopreservation of rabbit semen.(AU)

Early maturation of corpus luteum in rabbits - effect of sildenafil citrate on luteolytic capacity in the early luteal period

Background: Prostaglandin F2 alpha (PGF2 α) binds to the specific receptor (PTGFR) on the corpus luteum (CL) in mammals, inducing regression of the CL structure (luteolysis) and initiating a new cycle. While PGF2 α is effective only on mature CL, the immature CL structure (early luteal phase) resists PGF2 α. In this study, sildenafil citrate, which is used to increase blood flow in the genital organs for treating specific pregnancy issues in women, was administered during the early luteal phase in a rabbit model to test the hypothesis of enhancing blood flow to the CL, thereby promoting earlier maturation and enabling a response to PGF2 α. Materials, Methods & Results: The study was conducted in 2 sub-studies: clinical and molecular. A large number of rabbits were initially included in the sub-studies to ensure a sufficient number of pseudo-pregnant rabbits. Ovulation in rabbits was induced with buserelin acetate and was considered as day 0 of the study. The sub-studies were continued with rabbits whose pseudo-pregnancies were confirmed according to progesterone (P4 ) results. As a result, the studies were continued with a total of 41 pseudo-pregnant New Zealand female rabbits, 21 of which were included in the clinical sub-study and 20 in the molecular sub-study. In both sub-studies, on day 3 of the luteal period, rabbits in the treatment group received 5 mg/kg sildenafil citrate and all rabbits received a single dose of exogenous PGF2 α on day 4 to induce luteolysis. In the clinical sub-study, echotexture and intraovarian blood flow changes in the ovaries were determined by ultrasonography (USG) examination. In the molecular sub-study, the expression changes of Hypoxia Inducible Factor 1 Alpha (HIF1A) and Vascular Endothelial Growth Factor (VEGF) related to angiogenesis, Steroidogenic Acute Regulatory Protein (StAR) related to P4 metabolism, Prostaglandin-Endoperoxide Synthase 2 (PTGS2) related to prostaglandin (PG) mechanism and 15-Hydroxyprostaglandin Dehydrogenase (HPGD) genes at mRNA level were determined using Real Time Polymerase Chain Reaction (RT-PCR) in CL tissues obtained with ovariohysterectomy (OVH) at 1 and 12 h after PGF2 α injection. In addition, blood samples were collected for determine P4 levels from all rabbits. In the clinical sub-study; there was no difference between the groups in mean gray values (MGV), whereas there was a significant decrease in both pulsatile index (PI) and resistance index (RI) values at 40 min after PGF2 α injection (P < 0.05). In the molecular sub-study, it was determined that sildenafil citrate had no significant effect (P > 0.05) on the expression levels 1 and 12 h after PGF2 α injection. According to the results of the molecular sub-study, no significant effect of sildenafil citrate on the mRNA expression levels in the investigated genes was detected (P > 0.05). However, within each group, differences were found according to OVH time after PGF2 α injection. It was observed that PTGS2 and HPGD mRNA expressions decreased at the 12th h compared to the 1st h, while HIF1A expression increased (P < 0.05). Discussion: According to the results obtained from clinical and molecular sub-studies, it was determined that a single dose of sildenafil citrate (5 mg/kg) applied on the 3rd day of the luteal period did not contribute to the maturation process of the CL, did not increase blood flow, and was insufficient to break the resistance of the CL against PGF2 α applied on the 4th day of the luteal period. However, a significant decrease in the PI value at the 40th min after PGF2 α injection suggests that sildenafil citrate has a supportive effect, and that this decrease is also seen in the RI value, suggesting that its effect is insufficient against the vasoconstrictive effect of PGF2 α.