[Establishment and evaluation of a rabbit model of frozen shoulder induced by persistent strain injuries and ice compression].

OBJECTIVE: To evaluate the rabbit modle of frozen shoulder induced by persistent strain injuries and ice compression. METHODS: Twelve clean, healthy male New Zealand rabbits with a mass of (2 500±500) g were selected and randomly divided into a blank group and a control group with 6 rabbits in each group. In the control group, the rabbits were modeled with persistent strain injuries and ice compression, the general conditions of the rabbits and the active and passive activities of the shoulder joint were observed and their body weights were recorded. MRI was performed on the affected shoulder joints at 6 d and 29 d after modelling to observe the fluid and soft tissue;HE staining was used to observe the morphology of the rabbit biceps longus tendon and the synovial membrane of the joint capsule;Masson staining was used to observe the fibrous deposits of the rabbit biceps longus tendon and the synovial membrane of the joint capsule, and the fibrous deposits were analysed semi-quantitatively by Image J software. RESULTS: Six days after the end of modeling, the active movement of the shoulder joints in the control group was limited, the passive movement was not significantly limited, and they walked with a limp;29 days after the end of the modeling, the active and passive movements of the shoulder joints in the model group were severely limited. Compared with the blank group (2.50±0.14) kg, the body weight of the model group (2.20±0.17) kg was significantly reduced(P<0.01). MRI showed that 6 days after modelling, the muscles around the shoulder joint were not smooth in shape, the joint capsule structure was narrowed and a large amount of fluid was seen in the joint cavity;29 days after modelling, the muscles around the shoulder joint were rough in shape, structure of the joint capsule was unclear and the fluid in the joint cavity was reduced compared with 6 days after modelling. Pathological staining showed that the long-headed biceps tendon fibres in the control group were disorganised, curled or even broken, and the synovial tissue of the joint capsule was heavily vascularised, with collagen fibre deposits and severe inflammatory cell infiltration. The fiber deposition of the long head of biceps brachii in the model group [(23.58±3.41)%, (27.56±3.70)%] and synovial tissue [(41.78±5.59)%, (62.19±7.54)%] were significantly higher than those in the blank group [(1.79±1.03) %, (1.29±0.63) %] at 7 and 30 days after modeling and synovial tissue fiber deposition [(8.15±3.61) %, (11.29±7.10) %], as shown by the semi-quantitative analysis of Masson staining results by Image J software. And the longer the time, the more severe the fibrosis (P<0.01). CONCLUSION: The behavioral, imaging and pathological findings showed that the rabbit frozen shoulder model with persistent strain injuries and ice compression is consistent with the clinical manifestations and pathogenesis of periarthritis, making it an ideal method for periarthritis research.

Lactic acid bacteria reduce bacterial diarrhea in rabbits via enhancing immune function and restoring intestinal microbiota homeostasis.

BACKGROUND: Numerous previous reports have demonstrated the efficacy of Lactic acid bacteria (LAB) in promoting growth and preventing disease in animals. In this study, Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were isolated from the feces of healthy rabbits, and both strains showed good probiotic properties in vitro. Two strains (108CFU/ml/kg/day) were fed to weaned rabbits for 21 days, after which specific bacterial infection was induced to investigate the effects of the strains on bacterial diarrhea in the rabbits. RESULTS: Our data showed that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 interventions reduced the incidence of diarrhea and systemic inflammatory response, alleviated intestinal damage and increased antibody levels in animals. In addition, Enterococcus faecium ZJUIDS-R1 restored the flora abundance of Ruminococcaceae1. Ligilactobaciiius animalis ZJUIDS-R2 up-regulated the flora abundance of Adlercreutzia and Candidatus Saccharimonas. Both down-regulated the flora abundance of Shuttleworthia and Barnesiella to restore intestinal flora balance, thereby increasing intestinal short-chain fatty acid content. CONCLUSIONS: These findings suggest that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were able to improve intestinal immunity, produce organic acids and regulate the balance of intestinal flora to enhance disease resistance and alleviate diarrhea-related diseases in weanling rabbits.

Pharmacokinetic/pharmacodynamic evaluation of gamithromycin against rabbit pasteurellosis.

BACKGROUND: Gamithromycin is an effective therapy for bovine and swine respiratory diseases but not utilized for rabbits. Given its potent activity against respiratory pathogens, we sought to determine the pharmacokinetic profiles, antimicrobial activity and target pharmacokinetic/pharmacodynamic (PK/PD) exposures associated with therapeutic effect of gamithromycin against Pasteurella multocida in rabbits. RESULTS: Gamithromycin showed favorable PK properties in rabbits, including high subcutaneous bioavailability (86.7 ± 10.7%) and low plasma protein binding (18.5-31.9%). PK analysis identified a mean plasma peak concentration (Cmax) of 1.64 ± 0.86 mg/L and terminal half-life (T1/2) of 31.5 ± 5.74 h after subcutaneous injection. For P. multocida, short post-antibiotic effects (PAE) (1.1-5.3 h) and post-antibiotic sub-inhibitory concentration effects (PA-SME) (6.6-9.1 h) were observed after exposure to gamithromycin at 1 to 4× minimal inhibitory concentration (MIC). Gamithromycin demonstrated concentration-dependent bactericidal activity and the PK/PD index area under the concentration-time curve over 24 h (AUC24h)/MIC correlated well with efficacy (R2 > 0.99). The plasma AUC24h/MIC ratios of gamithromycin associated with the bacteriostatic, bactericidal and bacterial eradication against P. multocida were 15.4, 24.9 and 27.8 h in rabbits, respectively. CONCLUSIONS: Subcutaneous administration of 6 mg/kg gamithromycin reached therapeutic concentrations in rabbit plasma against P. multocida. The PK/PD ratios determined herein in combination with ex vivo activity and favorable rabbit PK indicate that gamithromycin may be used for the treatment of rabbit pasteurellosis.

Optimizing environmental enrichment for Sprague Dawley rats: Exemplary insights into the liver proteome.

BACKGROUND: Considering the expected increase in the elderly population and the growing emphasis on aging-related biomedical research, the demand for aged laboratory animals has surged, challenging established husbandry practices. Our objective was to establish a cost-effective method for environmental enrichment, utilizing the liver as a representative organ to assess potential metabolic changes in response to differing enrichment levels. METHODS: We conducted a six-month study involving 24 male Sprague Dawley rats, randomly assigned to four environmental enrichment groups. Two groups were housed in standard cages, while the others were placed in modified rabbit cages. Half of the groups received weekly playtime in an activity focused rat housing unit. We evaluated hormone levels, playtime behavior, and subjective handling experience. Additionally, liver tissue proteomic analysis was performed. RESULTS: Initial corticosterone levels and those after 3 and 6 months showed no significant differences. Yet, testosterone levels were lower in the control group by the end of the study (p = 0.007). We observed 1871 distinct proteins in liver tissue, with 77% being common across groups. In gene ontology analysis, no specific pathways were overexpressed. In semiquantitative analysis, we observed differences in proteins associated in lipid metabolism such as Apolipoprotein A-I and Acyl-CoA 6-desaturase, which were lower in the control group (p = 0.024 and p = 0.009). Rats in the intervention groups with weekly playtime displayed the least amount of reported distress during inspection or upon room entry and were less prone to accepting treats. Removing animals from their enclosure was most effortless for those in the large cage group. Over time, there was a decrease in conflicts among rats that interacted only twice weekly during playpen time. DISCUSSION: In summary, refining husbandry practices for aging rats is both simple and budget-friendly, with no apparent adverse effects on stress levels, animal development, or relevant metabolic changes in the liver.

Microstructural, Micromechanical Atlas of the Temporomandibular Joint Disc.

The temporomandibular joint (TMJ) disc is mainly composed of collagen, with its arrangement responding to efficient stress distribution. However, microstructural and micromechanical transformations of the TMJ disc under resting, functional, and pathological conditions remain unclear. To address this, our study presents a high-resolution microstructural and mechanical atlas of the porcine TMJ disc. First, the naive microstructure and mechanical properties were investigated in porcine TMJ discs (resting and functional conditions). Subsequently, the perforation and tear models (pathological conditions) were compared. Following this, a rabbit model of anterior disc displacement (abnormal stress) was studied. Results show diverse microstructures and mechanical properties at the nanometer to micrometer scale. In the functional state, gradual unfolding of the crimping cycle in secondary and tertiary structures leads to D-cycle prolongation in the primary structure, causing tissue failure. Pathological conditions lead to stress concentration near the injury site due to collagen interfibrillar traffic patterns, resulting in earlier damage manifestation. Additionally, the abnormal stress model shows collagen damage initiating at the primary structure and extending to the superstructure over time. These findings highlight collagen's various roles in different pathophysiological states. Our study offers valuable insights into TMJ disc function and dysfunction, aiding the development of diagnostic and therapeutic strategies for TMJ disorders, as well as providing guidance for the design of structural biomimetic materials.

AptaShield: A Universal Signal-Transduction System for Fast and High-Throughput Optical Molecular Biosensing.

Biosensing technologies are often described to provide facile, sensitive, and minimally to noninvasive detection of molecular analytes across diverse scientific, environmental, and clinical diagnostic disciplines. However, commercialization has been very limited mostly due to the difficulty of biosensor reconfiguration for different analyte(s) and limited high-throughput capabilities. The immobilization of different biomolecular probes (e.g., antibodies, peptides, and aptamers) requires the sensor surface chemistry to be tailored to provide optimal probe coupling, orientation, and passivation and prevent nonspecific interactions. To overcome these challenges, here we report the development of a solution-phase biosensor consisting of an engineered aptamer, the AptaShield, capable of universally binding to any antigen recognition site (Fab') of fluorescently labeled immunoglobulins (IgG) produced in rabbits. The resulting AptaShield biosensor relies on a low affinity dynamic equilibrium between the fluorescently tagged aptamer and IgG to generate a specific Förster resonance energy transfer (FRET) signal. As the analyte binds to the IgG, the AptaShield DNA aptamer-IgG complex dissociates, leading to an analyte concentration-dependent decrease of the FRET signal. The biosensor demonstrates high selectivity, specificity, and reproducibility for analyte quantification in different biological fluids (e.g., urine and blood serum) in a one-step and low sample volume (0.5-6.25 µL) format. The AptaShield provides a universal signal transduction mechanism as it can be coupled to different rabbit antibodies without the need for aptamer modification, therefore representing a robust high-throughput solution-phase technology suitable for point-of-care applications, overcoming the current limitations of gold standard enzyme-linked immunosorbent assays (ELISA) for molecular profiling.

Dry and liquid formulations of IBT-V02, a novel multi-component toxoid vaccine, are effective against Staphylococcus aureus isolates from low-to-middle income countries.

Staphylococcus aureus is the leading cause of skin and soft tissue infections (SSTIs) in the U.S. as well as more serious invasive diseases, including bacteremia, sepsis, endocarditis, surgical site infections, osteomyelitis, and pneumonia. These infections are exacerbated by the emergence of antibiotic-resistant clinical isolates such as methicillin-resistant S. aureus (MRSA), highlighting the need for alternatives to antibiotics to treat bacterial infections. We have previously developed a multi-component toxoid vaccine (IBT-V02) in a liquid formulation with efficacy against multiple strains of Staphylococcus aureus prevalent in the industrialized world. However, liquid vaccine formulations are not compatible with the paucity of cold chain storage infrastructure in many low-to-middle income countries (LMICs). Furthermore, whether our IBT-V02 vaccine formulations are protective against S. aureus isolates from LMICs is unknown. To overcome these limitations, we developed lyophilized and spray freeze-dried formulations of IBT-V02 vaccine and demonstrated that both formulations had comparable biophysical attributes as the liquid formulation, including similar levels of toxin neutralizing antibodies and protective efficacy against MRSA infections in murine and rabbit models. To enhance the relevancy of our findings, we then performed a multi-dimensional screen of 83 S. aureus clinical isolates from LMICs (e.g., Democratic Republic of Congo, Palestine, and Cambodia) to rationally down-select strains to test in our in vivo models based on broad expression of IBT-V02 targets (i.e., pore-forming toxins and superantigens). IBT-V02 polyclonal antisera effectively neutralized toxins produced by the S. aureus clinical isolates from LMICs. Notably, the lyophilized IBT-V02 formulation exhibited significant in vivo efficacy in various preclinical infection models against the S. aureus clinical isolates from LMICs, which was comparable to our liquid formulation. Collectively, our findings suggested that lyophilization is an effective alternative to liquid vaccine formulations of our IBT-V02 vaccine against S. aureus infections, which has important implications for protection from S. aureus isolates from LMICs.

Impact of different forms of selenium supplementation on growth and physiological performance of New Zealand white rabbits.

Forty-eight weaned male New Zealand White rabbits aged 6 weeks with an initial body weight of (709.67 ± 13 g) were randomly divided into six experimental groups (8 rabbits each) for 6-14 weeks of age experimental periods. The present study was planned to evaluate the effect of using different forms of Selenium element (inorganic, nanoparticles and organic) as dietary supplementation on productive performance of rabbits. Six experimental groups in completely randomized design were used. The first group (G1, control) was fed the basal diet to cover maintenance and production allowances. Rabbits in the other groups G2, G3, G4 and G5 were fed the basal diet supplemented with Nano- Se at 0.02, 0.03, 0.04 and 0.05 mg/kg diet, respectively. The 6th group (G6) was fed the basal diet supplemented with 0.1 mg/kg diet of salinized yeast (Se-yeast) as organic form. The results indicated that the highest values of nitrogen free extract (NFE) and crude fiber (CF) digestibility, live body weight, daily weight gain, hot carcass weight and dressing percentage were observed with those supplemented with Nano-Se at all levels compared with other treatments. However, feed conversion, net revenue and economic efficiency values were improved with Nano-Se groups followed by organic Se group in comparisons with the control group. Conclusively, the Nano-Se in rabbit's diet has a positive effect in improving rabbit's performance and economic efficiency compared to the inorganic Selenium.

Real-Time Temperature-Controlled Retinal Laser Irradiation in Rabbits.

Purpose: Subdamaging thermal retinal laser therapy has the potential to induce regenerative stimuli in retinal diseases, but validated dosimetry is missing. Real-time optoacoustic temperature determination and control could close this gap. This study investigates a first in vivo application. Methods: Two iterations of a control module that were optically coupled in between a continuous-wave commercial laser source and a commercial slit lamp were evaluated on chinchilla rabbits. The module allows extraction of the temperature rise in real time and can control the power of the therapy laser such that a predefined temperature rise at the retina is quickly achieved and held constant. Irradiations with aim temperatures from 45°C to 69°C were performed on a diameter of 200 µm and a heating time of 100 ms. Results: We analyzed 424 temperature-guided irradiations in nine eyes of five rabbits. The mean difference between the measured and aim temperature was -0.04°C ± 0.98°C. The following ED50 values for visibility thresholds could be determined: 58.6°C for funduscopic visibility, 57.7°C for fluorescein angiography, and 57.0°C for OCT. In all measurements, the correlation of tissue effect was higher to the temperature than to the average heating laser power used. Conclusions: The system was able to reliably perform temperature-guided irradiations, which allowed for better tissue effect control than simple power control. This approach could enhance the accuracy, safety, and reproducibility of thermal stimulating laser therapy. Translational Relevance: This study is a bridge between preclinical ex vivo experiments and a pilot clinical study.

A comprehensive synthetic library of poly-N-acetyl glucosamines enabled vaccine against lethal challenges of Staphylococcus aureus.

Poly-ß-(1-6)-N-acetylglucosamine (PNAG) is an important vaccine target, expressed on many pathogens. A critical hurdle in developing PNAG based vaccine is that the impacts of the number and the position of free amine vs N-acetylation on its antigenicity are not well understood. In this work, a divergent strategy is developed to synthesize a comprehensive library of 32 PNAG pentasaccharides. This library enables the identification of PNAG sequences with specific patterns of free amines as epitopes for vaccines against Staphylococcus aureus (S. aureus), an important human pathogen. Active vaccination with the conjugate of discovered PNAG epitope with mutant bacteriophage Qß as a vaccine carrier as well as passive vaccination with diluted rabbit antisera provides mice with near complete protection against infections by S. aureus including methicillin-resistant S. aureus (MRSA). Thus, the comprehensive PNAG pentasaccharide library is an exciting tool to empower the design of next generation vaccines.

F-actin architecture determines the conversion of chemical energy into mechanical work.

Mechanical work serves as the foundation for dynamic cellular processes, ranging from cell division to migration. A fundamental driver of cellular mechanical work is the actin cytoskeleton, composed of filamentous actin (F-actin) and myosin motors, where force generation relies on adenosine triphosphate (ATP) hydrolysis. F-actin architectures, whether bundled by crosslinkers or branched via nucleators, have emerged as pivotal regulators of myosin II force generation. However, it remains unclear how distinct F-actin architectures impact the conversion of chemical energy to mechanical work. Here, we employ in vitro reconstitution of distinct F-actin architectures with purified components to investigate their influence on myosin ATP hydrolysis (consumption). We find that F-actin bundles composed of mixed polarity F-actin hinder network contraction compared to non-crosslinked network and dramatically decelerate ATP consumption rates. Conversely, linear-nucleated networks allow network contraction despite reducing ATP consumption rates. Surprisingly, branched-nucleated networks facilitate high ATP consumption without significant network contraction, suggesting that the branched network dissipates energy without performing work. This study establishes a link between F-actin architecture and myosin energy consumption, elucidating the energetic principles underlying F-actin structure formation and the performance of mechanical work.

A novel rabbit model of atherosclerotic vulnerable plaque established by cryofluid-induced endothelial injury.

Acute thrombosis secondary to atherosclerotic plaque rupture is the main cause of acute cardiac and cerebral ischemia. An animal model of unstable atherosclerotic plaques is highly important for investigating the mechanism of plaque rupture and thrombosis. However, current animal models involve complex operations, are costly, and have plaque morphologies that are different from those of humans. We aimed to establish a simple animal model of vulnerable plaques similar to those of humans. Rabbits were randomly divided into three groups. Group A was given a normal formula diet for 13 weeks. Group C underwent surgery on the intima of the right carotid artery with - 80 °C cryofluid-induced injury after 1 week of a high-fat diet and further feeding a 12-week high-fat diet. Group B underwent the same procedure as Group C but without the - 80 °C cryofluid. Serum lipid levels were detected via ELISA. The plaque morphology, stability and degree of stenosis were evaluated through hematoxylin-eosin (HE) staining, Masson trichrome staining, Elastica van Gieson staining (EVG), and oil red O staining. Macrophages and inflammatory factors in the plaques were assessed via immunohistochemical analysis. The serum low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and total cholesterol (TC) levels in groups B and C were significantly greater than those in group A. No plaque formation was observed in group A. The plaques in group B were very small. In group C, obvious plaques were observed in the blood vessels, and the plaques exhibited a thin fibrous cap, a large lipid core, and partially visible neovascularization, which is consistent with the characteristics of vulnerable plaques. In the plaques of group C, a large number of macrophages were present, and matrix metalloproteinase 9 (MMP-9) and lectin-like oxidized LDL receptor 1 (LOX-1) were abundantly expressed. We successfully established a rabbit model of vulnerable carotid plaque similar to that of humans through the combination of cryofluid-induced endothelial injury and a high-fat diet, which is feasible and cost effective.

Bioengineering autologous cartilage grafts for functional posterior lamellar eyelid reconstruction: A preliminary study in rabbits.

The reconstruction of posterior lamellar eyelid defects remains a significant challenge in clinical practice due to anatomical complexity, specialized function, and aesthetic concerns. The ideal substitute for the posterior lamellar should replicate the native tarsoconjunctival tissue, providing both mechanical support for the eyelids and a smooth surface for the globe after implantation. In this study, we present an innovative approach utilizing tissue-engineered cartilage (TEC) grafts generated from rabbit auricular chondrocytes and a commercialized type I collagen sponge to reconstruct critical-sized posterior lamellar defects in rabbits. The TEC grafts demonstrated remarkable mechanical strength and maintained a stable cartilaginous phenotype both in vitro and at 6 months post-implantation in immunodeficient mice. When employed as autografts to reconstruct tarsal plate defects in rabbits' upper eyelids, these TEC grafts successfully restored normal eyelid morphology, facilitated smooth eyelid movement, and preserved the histological structure of the conjunctival epithelium. When applied in bilayered tarsoconjunctival defect reconstruction, these TEC grafts not only maintained the normal contour of the upper eyelid but also supported conjunctival epithelial cell migration and growth from the defect margin towards the centre. These findings highlight that auricular chondrocyte-based TEC grafts hold great promise as potential candidates for clinical posterior lamellar reconstruction. STATEMENT OF SIGNIFICANCE: The complex structure and function of the posterior lamellar eyelid continue to be significant challenges for clinical reconstructive surgeries. In this study, we utilized autologous auricular chondrocyte-based TEC grafts for posterior lamellar eyelid reconstruction in a preclinical rabbit model. The TEC grafts exhibited native cartilaginous histomorphology and comparable mechanical strength to those of the native human tarsal plate. In rabbit models with either tarsal plate defects alone or bilayered tarsoconjunctival defects, TEC grafts successfully restored the normal eyelid contour and movement, as well as supported preservation and growth of conjunctival epithelium. This is the first study to demonstrate autologous TEC grafts can be employed for repairing tarsal plate defects, thereby offering an alternative therapeutic approach for treating posterior lamellar defects in clinic settings.

Economic analysis of banana peel and sweet potato vines in diets for rabbits.

This study aimed to evaluate the costs of using banana peel (BP) and sweet potato vine (SPV) in rabbit diets. BP and SPV were chosen to replace maize and alfalfa hay, because, in addition to the ingredients having similar nutritional characteristics, they are among the most expensive ingredients in rabbit diets. Data were obtained through a biological assay carried out in the Cuniculture Laboratory of the Universidade Federal de Santa Maria, Santa Maria, RS, Brazil. Fifty New Zealand white rabbits, weaned at 35 days of age, were fed during the growth phase (35 to 84 days) with increasing levels of BP and SPV, replacing maize and alfalfa hay (T0, T25, T50, T75 and T100% replacement). A diet containing 100% replacement (T100) had the lowest cost per kilogram, which was R$ 1.18/kg, while the controlled diet was 57% more expensive, costing R$ 2.08/kg. The total operating cost to produce a rabbit with control treatment was R$10.93/head and at T100, it was R$6.51/head. The animal income for a live rabbit was R$ 24.08 and R$ 23.95 in treatments T0 and T100, respectively. Regarding the gain margin per animal (GMA), in TO it was R$ 13.16 while in T100 it was R$ 17.44, therefore the GMA was 32.55% higher when using the T100 diet. In conclusion, it is more economical and feasible to feed rabbits with diets containing 100% BP and SPV, replacing maize and alfalfa hay.

Dietary replacement of maggot meal for soybean meal: implication on performance indices, nutrient digestibility, nitrogen utilisation and carcass characteristics of grower rabbits.

A study was conducted to investigate the effect of replacing soybean meal (SBM) with maggot meal (MM) in growing rabbits' diets on their performance, nutrient digestibility, and carcass characteristics. In the 56 days feeding trials, sixty unsexed mixed breeds (New Zealand White x California) rabbits were allotted on a weight equalization basis into five dietary treatments where a standard corn-soybean meal based diet (0% of maggot meal) (MM0 diet) served as the while other diets had soybean meal replaced with MM at graded levels of 25, 50, 75 and 100% to give MM25, MM50, MM75, and MM100 diets respectively. Each treatment comprises of four replicates having three rabbits each (12 rabbits per treatment). Growth performance parameters were monitored and recorded weekly, carcass and organ weights evaluation was conducted on day 56. Nutrient digestibility commenced on the 56th day and lasted for 6 days. Feed and water were offered to the rabbits ad-libitum throughout the experimental period. All the performance parameters were significantly (P < 0.05) affected by MM inclusion in the diet of rabbits. Rabbits fed MM100 diet had the highest (P < 0.05) final weight (FW), total weight gain (TWG), and the best feed conversion ratio (FCR). The feed cost reduced (P < 0.05) with inclusion of MM in rabbit's diet. Feed cost per kg live weight (FC/LW) (1110.79 ₦/kg) and feed cost per kg weight gain (FC/WG) (1110.62 ₦/kg) was lowest (P < 0.05) for rabbits fed MM100 diet. Crude protein digestibility (CPD) (74.05%) was highest (P < 0.05) for rabbits fed the MM100 diet. The feeding of MM75 and MM100 diets to rabbits resulted in increased (P < 0.05) dry matter digestibility (DMD) (68.22 and 69.34%), nitrogen free extract digestibility (NFED) (65.52 and 65.22%) and neutral detergent fibre digestibility (NDFD) (70.05 and 69.58%). The highest (P < 0.05) nitrogen retained (NR) (2.10 g/d) occurred in rabbits fed the MM100 diet. The dressing percentage (DP) (71.01%) increased (P < 0.05) for rabbits fed the MM100 diet. The weight of forelimbs (10.48 and 10.45%) and hind limbs (17.42 and 18.07%) were highest (P < 0.05) for rabbits fed MM50 and MM100 diets respectively. Total gastrointestinal tract (GIT) and liver weight were highest (P < 0.05) for rabbits fed MM0 and MM100 diets respectively. It was concluded that MM can conveniently replace SBM in the diets of rabbits up to 100% for improved growth performance and increased nutrient digestibility. In addition, it can enhance DP and increase the carcass yield of rabbits.

Productive performance, digestibility, carcass traits and meat quality in rabbits fed triticale-based diets supplemented with xylanase.

Cereals such as triticale may contain high levels of xylans and arabinoxylans, limiting its use in diets since they act as anti-nutritional factors. The objective was to evaluate the effects of the enzyme xylanase included in triticale-based diets on productive performance, digestibility, carcass traits and meat quality in growing-finishing rabbits. Eighty rabbits (New Zealand X California breed), 35 days old, with an average initial live weight of 821 ± 26 g, were used. Twenty animals for treatment were used in each one of the fourth experimental treatments: 0, 4000, 8000 and 12,000 XU/kg of xylanase inclusion (XilaBlend 6X). The rabbits were fed ad libitum and fecal excretion was collected on days 7, 14, 21, 28 and 35 of the experimental period. At the end of the experimental period, the rabbits were slaughtered and carcass characteristics and meat quality were measured. A higher (P < 0.05) live weight was observed in rabbits fed diets with the addition of xylanase enzyme on days 4 and 7 of the experimental period. On the other hand, in the average total tract digestibility of organic matter, no significant difference was observed, similar to what occurred in the carcass traits and nutritional quality of the meat. The inclusion of 8000 XU/kg of xylanase enzyme provided the best values of apparent digestibility of total tract protein and dry matter on the finished stage of rabbits.

Evaluation of the effect of Carica papaya seed on the growth performance of fattening rabbits.

Successful breeding depends on feeding. The present study aims to evaluate the Carica papaya seed effect on the growth performance of rabbits. The zootechnical parameters studied are weight growth, average daily gain, Feed Conversion Ratio, and carcass characteristics of kits. The experiment was conducted on 48 rabbits, divided into 4 groups, for 6 weeks. Forty-eight rabbits were divided into four (04) groups of 3 repetitions of 4 rabbits. The animals were fed diets containing various levels of papaya seed powder at variable contents: 0% (group T0), 4% (group T1), 6% (group T2), and 8% (group T3). At the end of the experiment, three animals were slaughtered in each animal group to assess the quality of the carcasses and organs. 6% of the seeds of Carica papaya significantly improved (p < 0.05) the average daily gain of the kits: T2 (22.40 g / d) compared to the T0 group (11.32 g / d), T1 (12.20 g / d) and T3 (17.53 g / d). The best Feed Conversion Ratio (0.80) was recorded in the animals of group T2. In contrast, the highest carcass yield was recorded in the rabbits of group T3 (62.70%). In conclusion, 6% was optimal in the feed rations of fattened rabbits to improve production performance. Breeders can consider the benefits of introducing Carica papaya seeds into the rabbits' diet.

Formulation of Metoclopramide Hydrochloride-Loaded Lipid Carriers by QbD Approach for Combating Nausea: Safety and Bioavailability Evaluation in New Zealand Rabbit.

The focus of the research was to overcome the limitations of metoclopramide (MTC) when administered intranasally. The aim was to improve its bioavailability, increase patient compliance, and prolong its residence time in the nasal cavity. MTC-loaded liposomes were prepared by applying the film hydration method. A study was conducted to determine how formulation variables affected encapsulation efficiency (EE %), mean particle size (MPS), and zeta potential (ZP). The MTC-liposomes were further loaded into the in situ gel (gellan gum) for longer residence times following intranasal administration. pH, gelling time, and in vitro release tests were conducted on the formulations produced. In vivo performance of the MTC-loaded in situ gels was appraised based on disparate parameters such as plasma peak concentration, plasma peak time, and elimination coefficient compared to intravenous administration. When the optimal liposome formulation contained 1.98% of SPC, 0.081% of cholesterol, 97.84% of chloroform, and 0.1% of MTC, the EE of MTC was 83.21%, PS was 107.3 nm. After 5 h, more than 80% of the drug was released from MTC-loaded liposome incorporated into gellan gum in situ gel formulation (Lip-GG), which exhibited improved absorption and higher bioavailability compared to MTC loaded into gellan gum in situ gel (MTC-GG). Acceptable cell viability was also achieved. It was found out that MTC-loaded liposomal in situ gel formulations administered through the nasal route could be a better choice than other options due to its ease of administration, accurate dosing, and higher bioavailability in comparison with MTC-GG.

Keratin Formed Bioadhesive Ophthalmic Gel for the Bacterial Conjunctivitis Treatment.

Keratin has the potential to function as the gel matrix in an ophthalmic formulation for the encapsulation of the macrolide antibiotic azithromycin. The quality of this formulation was thoroughly evaluated through various analyses, such as in vitro release assessment, rheological examination, intraocular retention studies in rabbits, assessment of bacteriostatic efficacy, and safety evaluations. It is worth mentioning that the gel demonstrated shear thinning properties and exhibited characteristics of an elastic solid, thereby confirming its structural stability. The gel demonstrated a notable affinity for mucosal surfaces in comparison to traditional azithromycin aqueous solutions. In vitro release testing revealed that drug release transpired via diffusion mechanisms, following a first-order kinetic release pattern. Additionally, the formulated gel exhibited remarkable antibacterial efficacy against Staphylococcus aureus and Pseudomonas aeruginosa in bacteriostatic evaluations. Lastly, safety assessments confirmed that the gel eye drops induced minimal irritation and displayed no apparent cytotoxicity, indicating their good safety and biocompatibility for ocular application. Thus, these findings indicated that the prepared azithromycin gel eye drops complied with the requisite standards for ophthalmic preparations.

Biomimetic Mineralized 3D-Printed Polycaprolactone Scaffold Induced by Self-Adaptive Nanotopology to Accelerate Bone Regeneration.

Three-dimensional (3D)-printed biodegradable polymer scaffolds are at the forefront of personalized constructs for bone tissue engineering. However, it remains challenging to create a biological microenvironment for bone growth. Herein, we developed a novel yet feasible approach to facilitate biomimetic mineralization via self-adaptive nanotopography, which overcomes difficulties in the surface biofunctionalization of 3D-printed polycaprolactone (PCL) scaffolds. The building blocks of self-adaptive nanotopography were PCL lamellae that formed on the 3D-printed PCL scaffold via surface-directed epitaxial crystallization and acted as a linker to nucleate and generate hydroxyapatite crystals. Accordingly, a uniform and robust mineralized layer was immobilized throughout the scaffolds, which strongly bound to the strands and had no effect on the mechanical properties of the scaffolds. In vitro cell culture experiments revealed that the resulting scaffold was biocompatible and enhanced the proliferation and osteogenic differentiation of mouse embryolous osteoblast cells. Furthermore, we demonstrated that the resulting scaffold showed a strong capability to accelerate in vivo bone regeneration using a rabbit bone defect model. This study provides valuable opportunities to enhance the application of 3D-printed scaffolds in bone repair, paving the way for translation to other orthopedic implants.