Mature Rabbits Research Articles

Prevention of Fibrous Changes in the Model of Ophthalmosurgical Trauma in the Treatment of Glaucoma

The process of fibrosis in the area of newly formed outflow tracts during surgical treatment of glaucoma leads to a decrease in efficiency. Today, various approaches are used to reduce postoperative scarring. In some cases, the use of certain methods, as well as their combinations, does not bring the expected result. It is proposed to evaluate the antifibrotic effect of adipose tissue autograft in an experiment. This study considers an experimental model for preventing fibrotic changes in surgical trauma during glaucoma treatment.Objective: Development of a model and experimental clinical and morphological substantiation of the antifibrotic effect of adipose tissue autografting in the area of surgical trauma during glaucoma treatment.Material and methods. The studies were conducted on 10 eyes of laboratory animals (5 mature rabbits). The animals underwent surgery according to the volume of traumatic impact corresponding to non-penetrating surgery. Two groups were identified: the main group — 5 eyes (the left eye of the animal) surgically treated with the introduction of a fraction of adipose tissue into the surgical area, the comparison group — 5 eyes (the right eye of the animal) without autotransplantation of adipose tissue. The observation period was 1 month. During biomicroscopy on days 1, 3, 5, 7, 10, 15 and 30 after the intervention, the characteristics of the surgical area were assessed according to the Würzburg Clinical and Morphological Classification (WBCS). After the animals were withdrawn from the experiment, histological comparison of the tissue areas of the surgical areas was performed.Results. Comparison of the total index of the Würzburg Clinical and Morphological Classification shows that starting from the 5th day after the intervention, there is a clear distinctive dynamic between the study groups. In the group with the introduction of adipose tissue, there was minimal vascularization of the surgical area, with the original height and width of the formed cushion maintained throughout the observation period. Histological comparison confirms the absence of signs of formation of scar connective tissue in the area of operation in rabbits with autotransplantation of adipose tissue, while in the comparison group rabbits there is a pronounced tendency to scarring.Conclusions. The experimental model demonstrates the possibility of autotransplantation of adipose tissue into the sub-Tenon space in surgical treatment of glaucoma. The justification for the antifibrotic effect is obtained based on the obtained clinical and morphological data.

The Interstitial Gland as a Source of Pro- or Anti-Senescent Cells during Chinchilla Rabbit Ovarian Aging.

The aging ovary in mammals leads to the reduced production of sex hormones and a deterioration in follicle quality. The interstitial gland originates from the hypertrophy of the theca cells of atretic follicles and represents an accumulative structure of the ovary that may contribute to its aging. Here, reproductive and mature rabbit ovaries are used to determine whether the interstitial gland plays a crucial role in ovarian aging. We demonstrate that, in the mature ovary, interstitial gland cells accumulate lipid droplets and show ultrastructural characteristics of lipophagy. Furthermore, they undergo modifications and present a foamy appearance, do not express the pan-leukocyte CD-45 marker, and express CYP11A1. These cells are the first to present an increase in lipofuscin accumulation. In foamy cells, the expression of p21 remains low, PCNA expression is maintained at mature ages, and their nuclei do not show positivity for H2AX. The interstitial gland shows a significant increase in lipofuscin accumulation compared with the ovaries of younger rabbits, but lipofuscin accumulation remains constant at mature ages. Surprisingly, no accumulation of cells with DNA damage is evident, and an increase in proliferative cells is observed at the age of 36 months. We suggest that the interstitial gland initially uses lipophagy to maintain steroidogenic homeostasis and prevent cellular senescence.

SEMEN CHARACTERISTICS AND TESTICULAR MORPHOMETRY OF RABBIT BUCKS FED DIETARY LEVELS OF THYME (THYMUS VULGARIS)

A study was aimed at investigating the semen characteristics and testicular morphometry of rabbit bucks fed dietary levels of thyme (Thymus vulgaris). A total of 20 mature (seven months old) rabbit bucks were used for the study. The rabbit bucks were randomly allotted to four experimental diets (5/each) and fed for 8 weeks. The diet were formulated with the inclusion of thyme at 0, 5, 10 and 15g of thyme/kg of feed for T1, T2, T3, and T4 respectively. The Experiment was arranged in a Completely Randomized Design (CRD). Fresh experimental diets and clean water were made available ad libitium for the bucks throughout the experimental period. The results indicated that dietary inclusion of thyme significantly (P<0.05) affected all semen parameters except semen pH. Semen volume, forward motilty, live sperm (%) and abnormal sperm (%) of bucks in T4 and T3 were significantly (P<0.05) higher than those in other treatment groups. Results of testicular morphometry revealed that dietary inclusion of thyme resulted in a significant (P<0.05) increase in testis weight, testis volume and testis circumference with bucks in T4 and T3 outperforming those in other treatment groups. However, no significant difference (P>0.05) was observed in other testicular morphometric indices studied across the treatment groups. From the result, it was concluded that dietary inclusion of thyme at 10g/kg diet improved the semen characteristics and testicular morphometry of rabbit bucks.

REPRODUCTIVE PERFORMANCE OF CROSSBRED RABBIT DOES (ORYCTOLAGUS CUNICULUS) FED DIETARY ASCORBIC ACID SUPPLEMENTATION

Effect of dietary ascorbic acid supplementation was investigated on reproductive performance of crossbred rabbit does (Oryctolagus cuniculus) in a 13-week feeding trial. A total of 30 mature rabbit does of 18 to 20 weeks old with average weight of 2.75 kg were used. Ascorbic acid was included in the diets of the rabbits at levels of 0 (control), 100, 200, 300 and 400 mg/kg feed. The rabbits were randomly allotted to the diets (n=6 rabbits/treatments and housed individually. All data were subjected to general linear model while the significant differences in means were separated using pairwise-difference. The Results showed that rabbit does fed dietary ascorbic acid supplementation (200, 300 and 400 mg/kg diet) had significantly (P<0.05) higher litter size (6.25-8.29 vs. 4.48-6.00) and litter weight (400.00-5850.33 g vs. 300.00-3870.50 g) than their counterparts fed the control diet. However, does fed dietary ascorbic acid supplementation had significantly (P<0.05) lower total kit mortality (14.58, 20.53, 13.77 vs. 27.28%) compared to their counterparts fed the control diet. The Results of this study suggest that feed grade ascorbic acid supplementation at 200, 300 and 400 mg ascorbic acid/kg diet could improve litter performance of rabbit does.

EFFECT OF RAW, FERMENTED AND HOT WATER TREATED COCOA POD HUSK MEAL BASED DIETS ON THE REPRODUCTIVE TRACT MORPHOMETRY OF RABBIT BUCKS

This study was carried out to determine the effect of feeding raw, fermented and hot - water treated cocoa pod husk meal (CPHM) based - diets on the reproductive tract morphometry of rabbit bucks. A total of sixty (60) cross bred mature rabbit bucks were utilized and randomly allocated to twelve (12) experimental diets containing raw (T1, T2, T3& Ta), fermented (Ts. T6. T7, & Ts) and hot water treated (T9. T10, T1& T12) CPHM at 0.00, 12.50, 25.00 and 37.50 percent levels of inclusion respectively, in a 3 X 4 factorial arrangement using a CRD. The feeding trial lasted twenty one (21) weeks. Water and feed (formulated diets were both isonitrogenous 16% and isocaloric - 2500kcal/kgME) were provided ad-libitum. At the end of the feeding trial thirty six (36) rabbits (3 per treatment) were sacrificed in the laboratory, dissected and reproductive tracts obtained intoto, trimmed of fats and adhering tissues before being subjected to morphometric analysis. Results of the study revealed significant (P < 0.05) reduction in absolute weight values of the paired testes and epididymis as well as the length of the caput epididymis in rabbit bucks fed the raw CPHM diets, while fermented and hot-water treated CPHM recorded fluctuating trends. The respective absolute and relative weights as well as lengths of other parameters declined in values as the levels of raw CPHM inclusion increased, while other processed forms had no definite pattern without any significant difference (P > 0.05). These findings imply that processed cocoa pod husk meal (fermented and hot-water treated forms)could serves some useful purpose as a non-conventional feed resource in rabbit nutrition and physiology. It is therefore suggested that fermented and hot- water treated CPHM could be included up to 25.00 percent in diets meant for rabbits without fear of compromising their reproductive tract morphometryvis-a-vis reproductive potential.

Enhanced osteochondral repair by leukocyte-depleted platelet-rich plasma in combination with adipose-derived mesenchymal stromal cells encapsulated in a three-dimensional photocrosslinked injectable hydrogel in a rabbit model

IntroductionIntra-articular injection of adipose-derived mesenchymal stromal cells (ASCs) and/or platelet-rich plasma (PRP) have been reported to independently and synergistically improve healing of osteochondral lesions in animal models. However, their independent and combined effects when localized to an osteochondral lesion by encapsulation within a photocrosslinkable methacrylated gelatin hydrogel (GelMA) have not been explored. Herein we investigated a unique combination of allogeneic ASCs and PRP embedded in GelMA as a single-stage treatment for osteochondral regeneration in a rabbit model.MethodsThirty mature rabbits were divided into six experimental groups: (1) Sham; (2) Defect; (3) GelMA; (4) GelMA + ASCs; (5) GelMA + PRP; and (6) GelMA + ASCs + PRP.At 12 weeks following surgical repair, osteochondral regeneration was assessed on the basis of gross appearance, biomechanical properties, histological and immunohistochemical characteristics, and subchondral bone volume.ResultsIn terms of mechanical property reflecting the ability of neotissue to bear stress, PRP only group were significantly lower than the Sham group (p = 0.0098). On the other hand, ASCs only and ASCs combined with PRP groups did not exhibit significantly difference, which suggesting that incorporation of ASCs assists in restoring the ability of the neotissue to bear stresses similarly to native tissue (p = 0.346, p = 0.40, respectively). Safranin O in ASCs combined with PRP group was significantly higher than the Defect and GelMA only groups (p = 0.0009, p = 0.0017, respectively). Additionally, ASCs only and ASCs combined with PRP groups presented especially strong staining for collagen type II. Surprisingly, PRP only and PRP + ASCs groups tended to exhibit higher collagen type I and collagen type X staining compared to ASCs only group, suggesting a potential PRP-mediated hypertrophic effect.ConclusionRegeneration of a focal osteochondral defect in a rabbit model was improved by a single-stage treatment of a photocrosslinked hydrogel containing allogenic ASCs and autologous PRP, with the combination of ASCs and PRP producing superior benefit than either alone. No experimental construct fully restored all properties of the native, healthy osteochondral unit, which may require longer follow-up or further modification of PRP and/or ASCs characteristics.

Distraction osteogenesis in combined sequential use of external fixation and nailing (lengthening and then nailing): An experimental study in rabbits.

Limb lengthening relies on the process of distraction osteogenesis. The active periosteal bone formation has been detected in clinical practice with a lengthening and then nail (LATN) technique but has not been confirmed by experimental studies to date. The aim of this study is to compare the tissue regeneration of the distraction regenerate during tibial lengthening in rabbits using a LATN technique. This study was performed on 54 mature rabbits of the Soviet Chinchilla breed, which were divided into three groups of 18 animals. In group 1 (control), the tibia was lengthened in an external fixator. In group 2, the LATN technique was modeled and in group 3, lengthening over nail (LON) was modeled. The total duration of the experiment was 45 days. On the 10th, 15th, 20th, 30th, and 45th day X-ray, computed tomography and morphological studies were performed. In the experimental groups (2 and 3), a more pronounced periosteal bone formation in the area of regenerate was noted when compared to group 1. In group 2 (LATN), wide cortical plates were formed from the intermediate and periosteal areas. In this group, the maximum densitometric density values were noted. Endosteal bone formation was preserved in all groups. The LON and LATN techniques, when compared with the classical Ilizarov lengthening, do not demonstrate any deficiency in the tissue regeneration of the bone tissue at the regenerate sites. The most powerful bone structures are formed with the sequential use of the external fixation and nailing (LATN).

Growth, survival rate of New Zealand White, Dutch Rabbit and their crosses

Abstract. The aim of the study was to assess survival rate of crossbred New Zealand White and Dutch rabbit breed. A total of 16 mature rabbits of seven to nine months old, New Zealand White and Dutch were used for the study. Data obtained were subjected to analysis of variance ANOVA using SAS. The reproductive traits studied were litter size, litter birth weight, mean kit weight. The growth traits were: body weight, body length, ear length, chest circumference, hind limbs, thigh length, nose to shoulder and thigh circumference. The reproductive traits were significantly (P<0.05) affected by genetic group Pure and crosses. New Zealand White observed high litter size and litter birth weight at first, seventh, 14th and 21st day. Purebred Dutch had significant (P<0.05) high values for growth traits. The body weight 478.73±18.10, body length 33.12±0.42, ear length 9.10±0.09, chest circumference 18.24±0.45 and hind limbs 19.51±0.33 were significantly (P<0.05) high in crosses of Dutch x New Zealand White. Pre-weaning mortality and survival rate at weaning were 22.22% and 77.77% high in New Zealand White; 14.28% and 85.71% in Dutch and DUC x NZW; and 9.09% and 90.90% in NZW x DUC. In conclusion, New Zealand White x Dutch crosses demonstrated high survival rate and low pre-weaning mortality.

The biological role of clove oil in the diet of mature male rabbits on the physiological body functions, oxidative stress and physical semen properties

In an eight-week experiment conducted throughout the months of January and February, 2023, the goal of this study was to determine how changing the diet of mature male rabbits to include clove oil affected their body's physiological processes and the quality of their sperm. In this study, 24 mature rabbit bucks that were 8 months old and weighed an average of 2.650 g in the first production year were used. In a final randomized plan, the bucks were randomly assigned to two experimental groups, each with twelve rabbits. Bucks served as the control group in the first group and were fed a commercial pelleted food without any supplements. Each buck in the second group received one milliliter of clove along with the daily diet requirement from commercial pellets. Every two weeks, values for weight gain, feed consumption, testosterone levels, blood constituents, libido, and semen quality were assessed. The findings demonstrated that including clove oil in the diet of bucks rabbits resulted in a significant (P<0.01) improvement in each of daily feed intake, daily weight gain, testosterone hormone, and γ-globulin and a significantly (P<0.01) reduced glucose, cholesterol fraction levels in comparison to the control group. Additionally, adding clove oil increased (P<0.01) the rabbit bucks' physical semen attributes values. It was determined that including clove oil in the diet of male rabbits improved physiological body processes, produced hypercholesterolemia, and raised the quality of the rabbits' sperm without having a negative impact on liver or kidney function.

Induction of Osteogenesis After BMP-2 Injection in Rabbit Shoulders: A Novel Strategy for Managing Glenoid Bone Defect Associated with Anterior Shoulder Instability

Background: Bone morphogenic protein-2 (BMP-2) has been shown to promote bone formation. The purpose of this research was to determine if an injectable form of BMP-2 could induce bone formation in anteroinferior glenoid bone defects, which is a critical factor of anterior shoulder instability. The purpose of this study was to investigate bone formation in rabbit shoulders following BMP-2 injection into the anterior capsulolabral complex. We hypothesized that the amount of new bone would be greater in rabbit shoulders injected with BMP-2 than in those injected with normal saline. Methods: An experimental study was conducted on 40 shoulders of 20 mature rabbits. Twenty right shoulders were allocated to four groups according to injection dose (5 µg or 10 µg) and follow-up period after injection (4 or 8 weeks). Twenty left shoulders were injected with normal saline as controls. At 4 or 8 weeks after injection, all rabbits were sacrificed, and bone volumes, densities, and locations of bone formation were evaluated using micro-computed tomography (micro-CT). Histologic analysis was performed on all 40 shoulders. Results: Shoulders injected with BMP-2 showed significantly more bone formation than control shoulders in all treated groups (58.6 ± 60.5 mm3 vs. 25.6 ± 32.6 mm3, p = 0.001). Moreover, bone formation increased with dose and follow-up. Locations of bone formation were the lesser tuberosity, greater tuberosity, and anterior capsulolabral complex. Histologic analysis confirmed the micro-CT-detected bone formation by revealing the presence of activated osteocytes, abundant osteoblastic rimming, and woven bone matrix. Conclusion: The study confirms that BMP-2 injection into the anterior capsulolabral complex of rabbit shoulders promotes new bone formation in adjacent soft tissue areas. Study Design: Controlled laboratory study.

The ameliorative effect of bergamot oil nano-emulsion in stressed rabbit bucks: Influence on blood biochemical parameters, redox status, immunity indices, inflammation markers, semen quality, testicular changes and the expression of HSPs genes

This work explored the activities of bergamot oil nano-emulsion (NBG) in modulating blood biochemical parameters, redox status, immunity indices, inflammation markers, semen quality, testicular changes and the expression of HSPs genes in stressed rabbit bucks. Twenty-four mature rabbit bucks (5 months) were randomly divided into three groups; control group (NBG0) received 1 ml of distilled water, while the other two groups received NBG orally at doses of 50 and 100 mg/kg (bw) twice a week. The present study's findings revealed that treated groups had lower values of total and direct bilirubin, triglyceride, lactate dehydrogenase, and creatinine compared with NBG0 group (p < 0.05). NBG100 group recorded the greatest of total protein, albumin, GPx, T3 and T4 values as well as the lowest values of uric acid, MDA, and indirect bilirubin. Both treated groups showed significantly reduced 8-OhDG, Amyloid A, TLR 4, while significantly increased nitric oxide, IgA, IgM, TAC, and SOD levels. Semen characteristics such as volume, sperm count, sperm motility, normal sperm, and vitality were significantly higher in the NBG100 group compared to the NBG50 and NBG0 groups, whereas sperm abnormalities and dead sperm were significantly reduced. HSP70, HSP72, and HSPA9 gene overexpression showed that testicular integrity was maintained after buck received oral doses of 50 or 100 mg/kg of NBG. Existing findings indicate that oral administration of NBG improves heat tolerance in rabbit bucks primarily as e result of its antioxidant and anti-inflammatory effects.

Osteopontin (SPP1) expression on gallstone formation in rabbits fed with a lithogenic diet.

This research was designed to assess the influence of the administration of a lithogenic diet, hydrogen peroxide, and vitamin AD3E on rabbits' gallstone formation and to envisage the expression of osteopontin (OPN) in their hepatic tissues. Twenty-four healthy local mature rabbits of both genders were divided into four equal groups. At the end of the feeding period, samples of blood were taken from all rabbits after they had fasted overnight to estimate the serum lipid profile. And some of the hepatic tissue has been preserved at -28°C for molecular analysis and gene expression. The gallstones were formed 100% in the GIII and 50% in the GIV. The mRNA OPN expression showed a significant increase in the GIII when compared with other groups. In Groups III and II, the serum levels of total cholesterol, Triglyceride, L-C, low-density lipoprotein-choles, and VLDL-C were significantly increased when compared with GI, while in GIII, the serum level of high-density lipoprotein-cholesterol was significantly decreased when compared with GI. It was concluded that the expression of the mRNA OPN was increased in the hepatic tissue of gallstone-formed rabbits.

Enhancing semen quality, antioxidant status and sex hormones of V-line rabbit bucks fed on supplemented diets with dried moringa leaves

This study was conducted to evaluate the impact of dried moringa leaves (DML) on semen quality, immunoglobulin measurements, blood metabolic analysis, antioxidant status and sex hormones of V-line rabbit bucks. Twenty-four mature rabbit bucks of 7-8 months-old of proven fertility with an average weight (2.8 ± 0.4 kg) were classified into four treatments (basal diet with 0, 750, 1500 and 3000 mg DML/kg diet) and 6 bucks per treatment were used. Seminal plasma cholesterol (p = 0.013) and triglycerides (p = 0.0001) of all moringa supplemented rabbits were higher than the control. Moringa leaves enhanced (p < 0.05) serum testosterone, follicle stimulating hormone and luteinizing hormone. Total antioxidant capacity, superoxide oxidase, glutathione peroxidase and catalase in seminal plasma of moringa rabbits were higher (p < 0.05) than the control. Serum total lipid (p = 0.002), cholesterol (p = 0.008), triglycerides (p = 0.019) and blood urea (p < 0.05) were lower in DML rabbits. Moringa leaves improved total antioxidant capacity (p = 0.0001), glutathione peroxidase (p = 0.0001) and superoxide oxidase (p = 0.037) in rabbits versus control. Rabbits consuming DML had higher (p < 0.05) immunoglobulin IgG and IgM than control. Results suggest that DML improved rabbits’ antioxidant, and immunological status, semen quality, and sex hormones, but DML (750 mg/kg diet) is recommended because it was more effective than the other two high doses.

Morphological investigation of reparative processes in the area of the defect of cartilage tissue of the external ear of the rabbit after the local application of allogenic mesenchymal stem cells

Purpose: to study the features of the restoration of rabbits outer ear elastic cartilage tissue in the area of the defect after its filling with allogeneic mesenchymal stem cells (MSCs). Materials and methods: Studies were performed on 24 sexually mature rabbits. All animals under general anaesthesia underwent surgery to create a standardized linear defect and were divided into experimental (15 rabbits) and control (9 rabbits) groups. In the experimental group, the defect was filled with suspensions of MSCs in the amount of 5 million cells, and in the control group of cells was not introduced. MSCs were obtained from the umbilical cord of rabbits by the enzymatic method. After the first passage of the MSCs culture, was studied MSCs stem potential and tested ability to differentiating. Material for morphological studies was taken after 1, 2 and 3 months, cryostat sections were prepared hematoxylin-eosin and picrofuxin staining were performed according to van Gizon, as well as morphometry. Results: The introduction of suspensions of allogeneic MSCs in the experiment in the cartilage defect of the outer ear of rabbits causes healing with the activation of pre-existing embryonic cartilage cells, the appearance of cells in a state of division in the adjacent zone, activation of angiogenesis and promotes fibrotization with a predominance of loose connective tissue 1 month after surgery. After 3 months, a more pronounced activation of chondrogenesis is observed with the growth of chondrocytes and their increased number in lacunae, the appearance of isogenic groups of cells, which is combined with vascular activation and the growth of dense scar connective tissue,increased fibroblasts and the number of collagen fibers in the defect area, as well as in the absence of a complete restoration of the characteristic cartilage structure. At that time, in the control group, in the process of defect healing 1 month after the operation, along with the detection of a reduced zone of activation of cartilage chondrocytes and collagen fibers, the development of destructive-dystrophic processes of chondrocytes and the extracellular cartilage matrix was observed. The morphometry data quantitatively confirm a more pronounced activation of chondrogenesis in the areas adjacent to the cartilage defect under the conditions of MSC injection compared to the control. The difference is 20.8% 1 month after the operation and 14.2% 3 months later. The results obtained indicate the promise of using MSCs to activate reparative processes in the area of rabbits outer ear cartilage tissue defect.

Expedited gene delivery for osteochondral defect repair in a rabbit knee model: A one-year investigation

ObjectiveTo evaluate a single-step, gene-based procedure for repairing osteochondral lesions. DesignOsteochondral lesions were created in the patellar groove of skeletally mature rabbits. Autologous bone marrow aspirates were mixed with adenovirus vectors carrying cDNA encoding green fluorescent protein (Ad.GFP) or transforming growth factor-β1 (Ad.TGF-β1) and allowed to clot. The clotted marrow was press-fit into the defects. Animals receiving Ad.GFP were euthanized at 2 weeks and intra-articular expression of GFP examined by fluorescence microscopy. Animals receiving Ad.TGF-β1 were euthanized at 3 months and 12 months; repair was compared to empty defects using histology and immunohistochemistry. Complementary in vitro experiments assessed transgene expression and chondrogenesis in marrow clots and fibrin gels. In a subsequent pilot study, repair at 3 months using a fibrin gel to encapsulate Ad.TGF-β1 was evaluated. ResultsAt 2 weeks, GFP expression was seen at variable levels within the cartilaginous lesion. At 3 months, there was no statistically significant improvement (p ​> ​0.05) in healing of lesions receiving Ad.TGF-β1 and variability was high. At 12 months, there were still no significant difference (p ​> ​0.05) between the empty defects and those receiving Ad.TGF-β1 in the overall, cartilage, and bone scores. Variability was still high. In vitro experiments suggested that variability reflected variable transduction efficiency and chondrogenic activity of the marrow clots; using fibrin gels instead of marrow may address this issue but more research is needed. ConclusionsThis approach to improving the repair of osteochondral lesions needs further refinement to reduce variability and provide a more robust outcome.

Investigating the histological and structural properties of tendon gel as an artificial biomaterial using the film model method in rabbits

PurposeThis study aimed to evaluate the properties of tendon gel by investigating the histological and structural differences among tendon gels under different preservation periods using a rabbit model.MethodsForty mature female rabbits were divided into four groups, each containing ten rabbits, on the basis of in-vivo preservation periods of tendon gels (3, 5, 10, and 15 days). We created the Achilles tendon rupture models using the film model method to obtain tendon gels. Tensile stress was applied to the tendon gel to promote maturation. Histological and structural evaluations of the tendon gel were performed before and after applying the tensile force, and the results obtained from the four groups were compared.ResultsAlthough the day-3 and day-5 tendon gels before applying tensile stress were histologically more immature than the day-10 and day-15 gels, type I collagen fibers equivalent to those of normal tendons were observed in all groups after the tensile process. Based on the surface and molecular structural evaluations, the day-3 tendon gels after the tensile process were molecularly cross-linked, and thick collagen fibers similar to those present in normal tendons were observed. Structural maturation observed in the day-3 tendon gels caused by traction was hardly observed in the day-5, -10, and -15 tendon gels.ConclusionsThe day-3 tendon gel had the highest regenerative potential to become a normal tendon by applying a traction force.

Пероксидное окисление липидов в тканях семенников половозрелых кроликов при изучении хронической токсичности тиаметоксама

Thiamethoxam (TMX) is one of the most widely used new-class neonicotinoid insecticides worldwide. The present study was conducted to investigate the toxic effects of TMX on the reproductive system of mature male rabbits. To do this, sixteen adult chinchilla rabbits were divided into two equal groups. Animals of the first group were orally administered TMX at a dose of 250 mg/kg of body weight for 90 days. The second group served as control. A biochemical blood test performed at the end of the study showed that TMX induced a significant increase in the level of such an indicator as acid phosphatase, while total cholesterol concentrations were approximately the same in both groups. The results obtained also showed that the use of TMX stimulated the development of oxidative stress in the tissues of the testes of rabbits of the experimental group. Thiamethoxam also caused a significant increase in GST and MDA concentrations and a decrease in GSH levels. Thus, when studying the chronic toxicity of Thiamethoxam, it was found that it causes the development of oxidative stress in the tissues of the testicles of experimental rabbits.

Age-related changes in the viscoelasticity of rabbit lens characterised by surface wave dispersion analysis

The viscoelastic properties of the young and mature rabbit lenses in situ are evaluated using wave-based optical coherence elastography (OCE). Surface waves in the crystalline lens are generated using acoustic radiation force (ARF) focused inside the eyeball. Surface-wave dispersion is measured with a phase-stabilised optical coherence tomography (OCT) system. The Young’s modulus and shear viscosity coefficient are quantified based on a Scholte wave model. The results show that both elasticity and viscosity are significantly different between the young and mature lenses. The Young’s modulus of the lenses increased with age from 7.74 ± 1.56 kPa (young) to 15.15 ± 4.52 kPa (mature), and the shear viscosity coefficient increased from 0.55 ± 0.04 Pa s (young) and 0.86 ± 0.13 Pa s (mature). It is shown that the combination of ARF excitation, OCE imaging, and dispersion analysis enables nondestructive quantification of lenticular viscoelasticity in situ and shows promise for in vivo applications.

The influence of various coatings of hydroxyapatite bone carrier on the success of bone regeneration in rabbit calvarial defects: Histomorphometric and histological analysis

Background/Aim. The materials used nowadays for bone replacement do not fully meet the requirements for complete regeneration, which is why new ones are being tested. Despite numerous attempts to improve bone tissue regeneration, no fulfilling material has been found yet. This study investigated the influence of poly-lactide-co-glycolide (PLGA) and polyethyleneimine (PEI) as coatings for hydroxyapatite (HAP) bone carriers on bone tissue regenerative potential in rabbits? calvarial defect. Methods. Calvarial defects measuring 6 mm in diameter were made in 19 skeletally mature rabbits. Defects were filled with one of the following materials: PLGA coated HAP (HAP + PLGA), PEI coated HAP (HAP + PEI), and bovine HAP ? Bio-Oss? (positive control). Unfilled defects represented negative control. Histological analysis was performed in order to determine the inflammatory response of the host tissue. The formation of the new bone was evaluated using histomorphometric analysis. All analyses have been conducted in samples obtained 3, 6, and 9 weeks after implantation. Results. Three weeks post-implantation, a trend toward increased healing in the HAP + PLGA group compared to other investigated materials was noticed, with no statistically significant difference between the study groups (p &gt; 0.05). However, after 6 and 9 weeks, significant healing was observed in favor of the HAP coated with PLGA compared to other groups (p &lt; 0.05). Within this group, greater bone healing was observed compared to the HAP + PEI and Bio-Oss? groups. Conclusion. PLGA demonstrated greater coating potential compared to PEI with respect to osteogenesis improvement in bone reconstructive surgery.

Dynamics of Known Long Non-Coding RNAs during the Maternal-to-Zygotic Transition in Rabbit.

Simple SummaryWe first revealed the expression profile of rabbit known lncRNAs during embryo pre-implantation development and showed minor and major wave of zygotic lncRNAs synthesis. The study then selected the differentially expressed (DE) lncRNAs between consecutive stages and predicted their potential target genes. The GO and KEGG analyses suggested that the lncRNAs participate in the regulation of embryo cleavage and development. Additionally, the sequential degradation of maternal lncRNAs showed that, like maternal mRNAs, maternal lncRNAs degradation occurred via maternal and zygotic pathways and the late-degraded lncRNAs might play a role in the degradation of mRNAs through mRNA surveillance pathway.The control of pre-implantation development in mammals undergoes a maternal-to-zygotic transition (MZT) after fertilization. The transition involves maternal clearance and zygotic genome activation remodeling the terminal differentiated gamete to confer totipotency. In the study, we first determined the profile of long non-coding RNAs (lncRNAs) of mature rabbit oocyte, 2-cell, 4-cell, 8-cell, and morula embryos using RNA-seq. A total of 2673 known rabbit lncRNAs were identified. The lncRNAs exhibited dynamic expression patterns during pre-implantation development. Moreover, 107 differentially expressed lncRNAs (DE lncRNAs) were detected between mature oocyte and 2-cell embryo, while 419 DE lncRNAs were detected between 8-cell embryo and morula, consistent with the occurrence of minor and major zygotic genome activation (ZGA) wave of rabbit pre-implanted embryo. This study then predicted the potential target genes of DE lncRNAs based on the trans-regulation mechanism of lncRNAs. The GO and KEGG analyses showed that lncRNAs with stage-specific expression patterns promoted embryo cleavage and synchronic development by regulating gene transcription and translation, intracellular metabolism and organelle organization, and intercellular signaling transduction. The correlation analysis between mRNAs and lncRNAs identified that lncRNAs ENSOCUG00000034943 and ENSOCUG00000036338 may play a vital role in the late-period pre-implantation development by regulating ILF2 gene. This study also found that the sequential degradation of maternal lncRNAs occurred through maternal and zygotic pathways. Furthermore, the function analysis of the late-degraded lncRNAs suggested that these lncRNAs may play a role in the mRNA degradation in embryos via mRNA surveillance pathway. Therefore, this work provides a global view of known lncRNAs in rabbit pre-implantation development and highlights the role of lncRNAs in embryogenesis regulation.