Male Rabbits Research Articles

Acute, subacute, repeat dose toxicity and safety studies of BiosimCovex (COVID-19 Nosode) in animal model

Introduction: BiosimCovex, a coronavirus nosode’s biological preparation was sourced from preclinical samples. The study needs to investigate the acute, subacute oral toxicity of different homeopathic drugs. The acute, subacute, repeat dose toxicity and safety testing of this newly developed nosode were conducted as per the OECD and New Drug and Clinical Trial (NDCT 19) rules. Material and methods In acute, subacute, repeat dose toxicity study, the homeopathic drug was administered orally at body weight, and animals were observed for toxic symptoms for 14 days. The study design consisted of 10 animals (05 males and 05 females) in acute mice and rats, 48 animals (24 males and 24 females) in subacute/repeat dose rats, and 24 (12 males/12 females) in repeat dose rabbit studies. Results Results indicate that in the acute and subacute studies of the rat and mice, no mortalities or clinical signs were found. The body weight and body weight gain in rats were normal and decreased in mice in the acute study. The feed consumption was normal for rats and mice. In male rabbits’ body weight was decreased and in other groups body weight gain observed was normal. The clinical signs were found to be normal in rats and rabbits. Histopathology results reveal that the BiosimCovex has not produced any major reactive and toxic changes in all the systemic organs when administered by an oral route up to a high dose. Conclusion No toxicity was documented using acute, subacute, and repeat dose studies using BiosimCovex, a coronavirus nosode.

Pharmacokinetics, Fecal Output, and Grimace Scores in Rabbits Given Long-acting Buprenorphine or Fentanyl for Postsurgical Analgesia.

The New Zealand white rabbit (Oryctolagus cuniculus) is a frequently used surgical model. Pain management after surgery is a critical aspect of animal welfare. Recently, a long-acting buprenorphine formulation (Ethiqa XR; EXR) was approved for use in rats and mice but has not yet been investigated in rabbits. The current study aimed to determine whether a single subcutaneous dose of 0.15mg/kg of EXR could achieve and maintain therapeutic buprenorphine plasma concentrations (0.1ng/mL) for 72h in male and female rabbits. We also evaluated the safety profiles of EXR and the fentanyl patch (FP) by assessing fecal output after surgery, because opioids are known to decrease intestinal motility. Behavior and pain scores were compared for rabbits that received either EXR or the FP after undergoing an annulus puncture procedure to induce osteoarthritis. EXR at 0.15mg/kg SC provided a shorter time to onset and sustained analgesia for 72h in male and female rabbits, whereas the FP provided suboptimal analgesia after 48h. Both EXR and FP reduced fecal output after surgery. Output returned to baseline levels within 72h for the EXR group and remained slightly below baseline at 96h after surgery for the fentanyl group. Grimace pain scores revealed no significant difference between treatment groups. These results suggest that EXR is a safe and effective option for postoperative pain management in rabbits.

Evaluation of parietal pleural adhesion and invasion in subpleural lung cancer: value of B-mode ultrasound and contrast-enhanced ultrasound.

The parietal pleural adhesion/invasion of lung cancer can contribute substantially to poor prognosis and difficulty in surgery. The value of ultrasound in evaluating the parietal pleural adhesion or invasion (pleural adhesion/invasion) of lung cancer remains uncertain. This study investigated the value of B-mode ultrasound and contrast-enhanced ultrasound (CEUS) in diagnosing parietal pleural adhesion/invasion of subpleural lung cancer. The study animals included 40 male New Zealand white rabbits. A rabbit subpleural lung cancer model was constructed by injecting VX2 tumor tissue under ultrasound guidance. In the 1-3 weeks after subpleural lesion formation, parietal pleural adhesion/invasion of the largest subpleural lesion was evaluated with B-mode ultrasound and CEUS by two sonographers. The parietal pleural adhesion/invasion was also determined using the gold standard method of findings from anatomical and pathological examination. Ultimately, 34 rabbits were subjected to complete ultrasonic evaluation. There were 20 and 14 cases with and without parietal pleural adhesion/invasion, respectively, as confirmed by anatomical and pathological evaluations. The diagnostic sensitivity, specificity, and accuracy of sonographer 1 using B-mode ultrasound were 50.0% [95% confidence interval (CI): 26.0-74.0%], 100%, and 70.6% (95% CI: 54.5-86.7%), respectively; for CEUS, they were 90.0% (95% CI: 75.6-100.0%), 100.0%, and 94.1% (95% CI: 85.8-100.0%), respectively. The diagnostic sensitivity, specificity, and accuracy of sonographer 2 using B-mode ultrasound were 45.0% (95% CI: 21.1-68.9%), 92.9% (95% CI: 77.5-100.0%), and 64.7% (95% CI: 47.8-81.6%), respectively; for CEUS, they were 85.0% (95% CI: 67.9-100.0%), 100.0%, and 91.2% (95% CI: 81.1-100.0%), respectively. The diagnostic accuracy of sonographer 1 was higher with CEUS than with B-mode ultrasound, but not significantly so (94.1% vs. 70.6%; P=0.08). The diagnostic accuracy of sonographer 2 was significantly higher with CEUS than with B-mode ultrasound (91.2% vs. 64.7%; P=0.03). The interrater reliability was higher for CEUS than for B-mode ultrasound (κ=0.941 vs. κ =0.717). Based on an animal model, B-mode ultrasound and CEUS both exhibited good diagnostic efficacy and interrater reliability in evaluating parietal pleural adhesion/invasion of subpleural lung cancer although CEUS outperformed B-mode ultrasound for both measures.

Evaluation and 3D imaging of mineral structure changes of the rabbit (New Zealand) skull during developmental periods.

This study aimed to determine the morphometric measurements anatomically and CT images of skulls of healthy male and female rabbits during postnatal development, to analyse the data statistically and to demonstrate the structural changes in bone. A total of 40 rabbits (20 females and 20 males) were divided into four groups including prepubertal period (group I (0-1 month)), period between adolescence and adulthood (group II (3-5 month)) and later (young adult period as group III (1-3 years) and old adult period as group IV (3-5 years)), with five animals in each group. After the morphometric measurements, the surface area and volume values of the skull were calculated. The skulls were reconstructed using a 3D Slicer (5.0.2), which is used for 3D modelling. The cranial bones in each group were then crushed using a grinder so that the powdered samples were obtained for XRF (X-ray fluorescence technique). The p-value was statistically highly significant between group and gender (p < 0.001). In morphometric measurements, males were generally higher than females. Only PL, GBOC and GNB measurements were higher in females. The p-value between groups (in all measurements), between genders (in TL, GLN, FL, VL, OZB and GBN parameters) and between groups and genders (in TL, DL and VL parameters) was statistically highly significant (p < 0.001). The p-value between the groups, p-value between sexes and p-value between group and sex in Si, P, K, Ca, Ni, Zn, Sr, Sr and Ca/P elements were statistically significant (p < 0.001). Consequently, metric, volume and surface area measurements were taken through 3D modelling of skull bone in prepubertal period (group I), period between adolescence and adulthood (group II) and later (young adult period as group III and old adult period as group IV) of rabbits and the change in the mineral structure during postnatal development and effect of sex on this change were investigated. This might be the first study to assess both metric and mineral changes at four age intervals taken during the life span of rabbits.

Balloon neck-plasty to create a wide-necked aneurysm in the elastase-induced rabbit model.

The elastase-induced aneurysm (EIA) model in rabbits has been proposed for translational research; however, the adjustment of aneurysm neck size remains challenging. In this study, the technical feasibility and safety of balloon neck-plasty to create a wide-necked aneurysm in rabbit EIA model were investigated. Male New Zealand White rabbits (N = 15) were randomly assigned to three groups: group A, EIA creation without neck-plasty; group B, neck-plasty immediately after EIA creation; group C, neck-plasty 4 weeks after EIA creation. The diameter of balloon used for neck-plasty was determined 1 mm larger than origin carotid artery diameter. All rabbits were euthanized 4 weeks after their final surgery. Aneurysm neck, height, dome-to-neck (D/N) ratio, and histologic parameters were compared among the groups. Aneurysm creation was technically successful in 14 out of 15 rabbits (93.3%), with one rabbit experiencing mortality due to an adverse anesthetic event during the surgery. Saccular and wide-necked aneurysms were successfully created in all rabbits. Aneurysm neck was significantly greater in groups B and C compared to group A (all P < .05). D/N ratio was significantly lower in groups B and C compared to group A (all P < .05). Additionally, tunica media thickness, vessel area, and luminal area were significantly greater in groups B and C compared to group A (all P < .05). These variables were found to be significantly greater in group B compared to group C (all P < .05). The creation of a wide-necked aneurysm using balloon neck-plasty after elastase induction in rabbits has been determined to be technically feasible and safe.

Role of preservation methods using deep-freezing and liquid nitrogen in bone allograft characteristics: An in vitro study.

Bone grafting has emerged as a key solution in bone defect management such as allograft, graft of bone from another individual. However, bone allografts usually undergo rigorous preparation to eliminate immune-triggering elements. The deep-freezing methods may delay graft use, while cryopreservation using liquid nitrogen allows rapid freezing but may alter graft characteristics. The aim of this study was to investigate the post-preservation changes in bone allograft characteristics and to compare the effectiveness of deep-freezing and liquid nitrogen methods using animal model. An experimental study using a post-test only control group design was conducted. Fresh-frozen femoral cortical bone was obtained from male New Zealand white rabbits. Preservation by deep-freezing involved placing bone samples in a -80°C freezer for 30 days. For liquid nitrogen preservation, bone grafts were immersed in liquid nitrogen for 20 min, followed by a 15-min rest at room temperature and a final immersion in 0.9% sodium chloride at 30°C for 15 min. Bone samples then underwent evaluation of cell viability, compression, and bending tests. Cell viability test employed the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and the compression and bending tests used the Universal Testing Machine (UTM). Independent Student t-test or Mann-Whitney U test were used to compare the methods as appropriate. Our study found that the use of deep-freezing and liquid nitrogen resulted in similar outcomes for cell viability, compression, and bending tests, with p-values of 0.302, 0.745, and 0.512, respectively. Further exploration with larger sample sizes may help to optimize the methods for specific applications.

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

To evaluate the rabbit modle of frozen shoulder induced by persistent strain injuries and ice compression. 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. 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). 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.

Three-dimensional morphometry of kidney in New Zealand rabbit using unbiased design-based stereology.

The rabbit is widely used as a laboratory animal in experimental models of kidney diseases. This species is also important from a veterinary perspective as a companion animal. Stereology has been accepted as an accurate approach to kidney morphometry. The objective of the present project was to provide normal quantitative stereological parameters for adult rabbit kidneys. The left kidneys of five adult male New Zealand rabbits were used. Isotropic sections were obtained using the orientation method. Total kidney volume was calculated by the Cavalieri principle. The volume fraction of the renal structures was estimated using the point counting system. The lengths of the proximal convoluted tubule (PCT) and distal convoluted tubule (DCT) were calculated using counting frames. The total glomerular number was accounted for using the physical/fractionator technique. The mean glomerular volume was obtained by dividing the total volume of glomeruli by their total number. The total volume of rabbit kidneys calculated was 10.39 ± 1.98 cm3. The fractional volume of the kidney cortex and medulla accounted for 57.79 ± 0.65% and 42.2 ± 0.65%, respectively. The total glomerular volume was 2.18 ± 0.32% of the whole kidney. The total number of glomeruli in the rabbit kidney was estimated as 204.68 ± 12 × 103. The mean glomerular volume measured 1.07 ± 0.12 × 106 μm3. The total length of PCT and DCT was 2.96 ± 0.29 km and 1.38 ± 0.24 km, respectively. These findings can be used as a reference in experimental nephrology research and may help to expand the knowledge of nephrology in mammals by comparing with available data on humans and other species. RESEARCH HIGHLIGHTS: Three-dimensional morphometry of adult rabbit kidney structures was analyzed using quantitative stereology. Total volume of kidney, fractional volume of cortex and medulla, length of renal tubules and number of nephrons were estimated. These three-dimensional morphometrical data can be used as a reference in experimental nephrology research and may help to expand the knowledge of nephrology in mammals.

Renal Artery Coil Embolization as an Endovascular Approach for Establishing a Rabbit Model of Chronic Kidney Disease

PurposeTo investigate the safety and feasibility of renal artery coil embolization for establishing chronic kidney disease (CKD) in rabbits. Materials and MethodsTen male adult New Zealand rabbits underwent renal artery coil embolization. Initially, the main renal artery on 1 side was completely embolized, followed by embolization of approximately two-thirds of the primary branches of the contralateral renal artery 1 week later. Four rabbits were randomly chosen for sacrifice at 4 weeks after embolization, whereas the remaining 6 were sacrificed at 8 weeks after embolization. The assessment encompassed the animals’ general condition, angiography, biochemical parameters, inflammatory markers, and histopathological examination of the kidneys and hearts. ResultsFour weeks after embolization, serum creatinine level showed a substantial increase (2.4 mg/dL [SD ± 0.6]; P = .009 vs baseline), with a subsequent 4.12-fold elevation at 8 weeks after embolization (4.9 mg/dL [SD ± 1.4]; P < .001 vs baseline). Additionally, considerable increases in serum blood urea nitrogen, calcium, and potassium ions were observed at 8 weeks after embolization (58.3 mg/dL [SD ± 19.0]; P < .001 vs baseline; 23.1 mg/dL [SD ± 4.4]; P < .001 vs baseline; and 6.3 mEq/L [SD ± 0.7]; P < .001 vs baseline, respectively). The completely embolized kidney exhibited notable atrophy, severe fibrosis, and cortical calcification, whereas the contralateral partially embolized kidney displayed compensatory hypertrophy, along with glomerulosclerosis, tubular dilation, tubular casts, and interstitial fibrosis. ConclusionsRenal artery coil embolization proved to be effective and safe for establishing a CKD model in rabbits.

Development and evaluation of a pH-responsive Mimosa pudica seed mucilage/β- cyclodextrin-co-poly(methacrylate) hydrogel for controlled drug delivery: In vitro and in vivo assessment

In this comprehensive investigation, a novel pH-responsive hydrogel system comprising mimosa seed mucilage (MSM), β-cyclodextrin (β-CD), and methacrylic acid (MAA) was developed via free radical polymerization technique to promote controlled drug delivery. The hydrogel synthesis involved strategic variations in polymer, monomer, and crosslinker content in fine-tuning its drug-release properties. The resultant hydrogel exhibited remarkable pH sensitivity, selectively liberating the model drug (Capecitabine = CAP) under basic conditions while significantly reducing release in an acidic environment. Morphological, thermal, and structural analyses proved that CAP has a porous texture, high stability, and an amorphous nature. In vitro drug release experiments showcased a sustained and controlled release profile. Optimum release (85.33 %) results were recorded over 24 h at pH 7.4 in the case of MMB9. Pharmacokinetic evaluation in healthy male rabbits confirmed bioavailability enhancement and sustained release capabilities. Furthermore, rigorous toxicity evaluations and histopathological analyses ensured the safety and biocompatibility of the hydrogel. This pH-triggered drug delivery system can be a promising carrier system for drugs involving frequent administrations.

Effect of fermented Cassava sievate and tiger nut shaft on growth performance, blood profile and immunological parameters in male rabbits.

This study examined the effects of using mushroom mycelium to ferment tigernut and cassava pulp on the growth performance, haematology and immunology of rabbits. Seventy-five New Zealand Bulk grower rabbits were randomly distributed to four treatment groups and a control group in a completely randomized approach. The treatment groups were fed with formulated experimental diets containing one of fermented tigernut drink by-product (FT), fermented cassava sievate (FC), unfermented tigernut drink by-product (UT), or unfermented cassava sievate (UC). The control group was fed a basal diet with no additives. The proximate composition of the fermented feed was analyzed. The weight gain of the animals was, 834.5, 633, 790, 510, and 706g for control, FT, FC, UT, and UC respectively. The packed cell volume (PCV) for animals in the control group, FT, and FC are 34.33, 37.26, and 32.29% respectively. The red blood cell (RBC) of the FT was favourably improved (5.53 × 1012/L) compared to those of UT (2.28 × 1012/L), while there was a reduction in the red blood cell count of FC group (1.02 × 1012/L). Conclusively, the inclusion of fermented tiger nut drink by-product in rabbit feed improved the PCV and RBC of the rabbits' understudy but did not affect their growth performance.

Comparison of Different Suture Techniques on Nasal Soft Tissue Envelope to Prevent Supratip Deformity: A Histologic Study.

Studies have described various surgical maneuvers in rhinoplasty to limit thickening from excessive scarring in the supratip region. This study aimed to compare the effectiveness of three maneuvers-a simple suture, a U suture, and bolster dressing-used to avoid supratip deformity in a rabbit model. Thirty-two male New Zealand white rabbits were included. The animals were divided into four groups, and dissection was performed in the supra-perichondrial plane up to the supratip region through an open rhinoplasty incision. After dissection, the following approaches were applied to the supratip region: Group 1, simple approximation suture; Group 2, U suture; Group 3, bolster dressing; and Group 4 (control group), no suture. All animals were sacrificed after 12weeks. Histological analysis was performed. In Group 4, scar thickness was significantly greater than in the other groups (p<0.05). Group 3 had greater scar thickness than Group 2 (p<0.05). The ratio of scar thickness to skin thickness was higher in Group 4 compared with the other groups (p<0.05). Finally, there was no difference in the ratio of scar thickness to skin thickness between Groups 1, 2, and 3 (p>0.05). In this study, it was concluded that surgical methods using sutures in the supratip region reduced scar thickness in a rabbit model, and these surgical methods had similar levels of effectiveness. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Study of Toxicity Resistance of Fusarium incarantum Isolated from Broad Bean by Arum maculate Leaf Extract in Adult Male Rabbits

Fungus isolates were obtained from the roots and leaves of the infected broad bean from Hawija district of Kirkuk city and isolated on the medium of PDA by examining its morphological and phenotypic characteristics of the fungus and the shape of conidia. In this study, 16 male rabbits were brought from the local markets of the city of Kirkuk and divided into 4 groups, each group consisting of 4 rabbits, the first group includes a control group, the second group is an infected group, the third group is an infected group that was treated with 50 mg of plant leaf extract, and an infected group was treated with 100 mg of leaf extract, after which Oxidative stress factors levels were checked. Oxidative stress factors showed high levels of MDA in infected rabbits compared to normal rabbits (P &lt; 0.05), while GSH and catalase levels appeared lower compared to MDA in infected rabbits (P &lt; 0.05), while in the group of rabbits treated with leaf extract 50 mg and 100 mg) showed few changes in concentrations MDA, GSH and Catalase compared to normal rabbits (P &lt; 0.05).

Impact of dietary Moringa oleifera leaf supplementation on gut morphometry, behaviour and physiological parameters in growing male rabbits

AbstractMoringa oleifera (MO), a cultivated species of the Moringa, is known for its high concentration of essential nutrients that promote growth. To assess its impact on rabbits' gut morphometric, behavioural, and physiological parameters, a study was conducted using sixty growing male white New Zealand rabbits at 40 days old. The rabbits were divided into four groups and supplemented with dried MO leaves at varying levels (0%, 0.5%, 1% and 2% of body weight) for four weeks. The results revealed significant increases in organ weights, such as liver and intestinal length, and the height of intestinal villi and crypt depth in the large intestine. The muscular layer's and submucosa's thickness also increased in different parts of the intestine in rabbits fed with MO compared to the control group. No significant effect was observed on the caecum mucosa depth. Interestingly, no significant differences were found in body weight or weight gain between the Moringa supplementation groups and the control group. However, rabbits offered 0%, 0.5% and 1% MO spent more time feeding and resting than those given 2% MO. The grooming and sniffing percentage remained unaffected by Moringa supplementation. Regarding blood parameters, rabbits that received MO leaves in their diet showed improvements in red blood cell count, haemoglobin levels, packed cell volume, white blood cell count, neutrophil count, total protein, globulin, and A/G ratio. Moreover, there was a significant decrease in malondialdehyde levels and an increase in glutathione and high‐density lipoprotein levels, indicating an antioxidative effect. Overall, the study concluded that MO leaves supplementation in the rabbit diet positively influenced the rabbits' health by modulating the immune system, improving histological aspects of the intestine, liver, and spleen, and enhancing physiological parameters through its antioxidative properties.

Clerodendron splendens leaf extract supplementation in weaner rabbits: impact on growth performance, haematology and intestinal microbial population

This experiment was carried out at Sumitra Research Institute, Gujarat, India to investigate the effect of supplementing Clerodendron splendens leaf extract on the growth performance, intestinal microbial population and some heamatological parameters. A total of fifty cross breed male rabbits (New Zealand white × Chinchilla) with initial body weight of 502 ± 0.80 g and weaned at five weeks of age was used for the experiment. On arrival, animals were quarantined for 14 days, stratified based on their body weight and randomly distributed into five groups consisting of 10 rabbits each in a completely randomized design. Experimental diet (basal) which was adequate in all nutrients; rabbits in group 1(G1) was fed basal diet only while G2, G3, G4 and G5 were fed basal diet with Clerodendron splendens leaf extract at 0.2 mL, 0.4 mL, 0.6 mL and 0.8 mL/day respectively. Average daily weight gain and average daily feed intake of rabbits fed 0 mL (control; group 1), 0.2 mL (group 2) were similar to those given 0.4 mL (group 3) and 0.6 mL (group 4) (P &gt; 0.05) but significantly lower than those in group 5 (0.8 mL). Average daily feed intake also increased in rabbits fed 0.8 mL (91.11 g) in group 5 followed by 0.6 mL (89.26 g), 0.4 mL (89.26 g), 0.2 mL (89.17 g) and 0 mL (89.12 g) in group 4, 3, 2 and 1 respectively. Higher mortality of 2 % was recorded in group 1 while none was recorded in the other treatment (P &lt; 0.05). Escherichia coli and Lactobacillus sp., count were significantly (P &lt; 0.05) different among the group. Pack cell volume, haemoglobin, red blood cell, white blood cell, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular volume, lymphocytes and neutrophil count were not significantly (P &gt; 0.05) influenced by the treatment. However, values were within the established range for healthy rabbits. It was concluded that supplementation of Clerodendron splendens leaf extract up to 0.8 mL/day had no negative effect on the performance and health status of rabbits.

EFFECT OF SEX AND AGE ON MORPHOMETRIC, PHYSIOLOGICAL AND BLOOD PROFILE OF MIXED BRED RABBIT

This study was conducted to assess the morphometric, physiological and blood parameters of mixbred rabbits at different ages. One hundred and sixty rabbits comprising New Zealand White and Chinchilla Crossbreds were used. Body weight and body linear parameters were measured and recorded on weekly basis. Generalised Linear Model Procedure of SAS software was used to analyse the data set to examine the effects of sex and age on these parameters. The results indicated that sex significantly (P&lt;0.05) affected morphometric and physiological parameters at 4, 8, 12, 32 and 48 weeks. Does (female rabbits) performed better than bucks (male rabbits) in almost all the traits studied. Buck at 8 weeks had higher rectal temperature while, higher values for pulse rate were recorded among the does and bucks at 32 weeks. Higher respiratory rate was observed in bucks at 48 weeks and for does at 32-48 weeks. Sex however had no significant effect on all haematological parameters. Sex had significant effect (P&lt;0.05) on aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphate (ALP), cholesterol (CHOL), triglyceride (TRG), low density lipoprotein (LDL), urea, creatinine and globulin (GLOB) of the crossbred rabbits at different ages. The higher aspartate amino transfererase (AST), alanine amino transferase (ALT), alkaline phosphate (ALP), cholesterol (CHOL), triglyceride (TRG), low density lipoprotein (LDL), globulin (GLOB) and urea were recorded in bucks at 48 weeks while the lowest low-density lipoprotein (LDL) was recorded for bucks at 32 weeks but creatinine was higher at 48 weeks of age among the does. Age had significant (P&lt;0.05) effect on morphometric, physiological and blood parameters. The highest rectal temperature was recorded at 8 weeks of age while highest respiratory rate was recorded for rabbits at 48 weeks. The higher creatinine, basophils and urea values were recorded for rabbits at 48 weeks old. Body weight influenced the morphometric, physiology and blood parameter of crossbred rabbits. It can be suggested to rabbit farmers that sex and age must be taken into account for optimal production.

Comparison of 3 Different Surgical Techniques for Rotator Cuff Repair in a Rabbit Model: Direct Suture, Inlay Suture, and Polyether Ether Ketone (PEEK) Suture Anchor

Background: Rotator cuff tears have been repaired using the transosseous method for decades. The direct suture (DS) technique has been widely used for rotator cuff tears; however, the retear rate is relatively high. Suture anchors are now used frequently for rotator cuff repair (RCR) in accordance with recent developments in materials. However, polyether ether ketone (PEEK) may still cause complications such as the formation of cysts and osteophytes. Some studies have developed the inlay suture (IS) technique for RCR. Purpose/Hypothesis: To compare how 3 different surgical techniques—namely, the DS, IS, and PEEK suture anchor (PSA)—affect tendon-bone healing after RCR. We hypothesized that the IS technique would lead to better tendon-to-bone healing and that the repaired structure would be similar to the normal enthesis. Study Design: Controlled laboratory study. Methods: Acute infraspinatus tendon tears were created in 36 six-month-old male rabbits, which were divided into 3 groups based on the technique used for RCR: DS, IS, and PSA. Animals were euthanized at 6 and 12 weeks postoperatively and underwent a histological assessment and imaging. The expression of related proteins was demonstrated by immunohistochemistry and immunofluorescence staining. Mechanical properties were evaluated by biomechanical testing. Results: At 12 weeks, regeneration of the enthesis was observed in the 3 groups. However, the DS group showed a lower type I collagen content than the PSA and IS groups, which was similar to the results for scleraxis. The DS group displayed a significantly inferior type II collagen expression and proteoglycan deposition after safranin O/fast green and sirius red staining. With regard to runt-related transcription factor 2 and alkaline phosphatase, the IS group showed upregulated expression levels compared with the other 2 groups. Conclusion: Compared with the DS technique, the PSA and IS techniques contributed to the improved maturation of tendons and fibrocartilage regeneration, while the IS technique particularly promoted osteogenesis at the enthesis. Clinical Relevance: The IS and PSA techniques may be more beneficial for tendon-bone healing after RCR.

Adapting Fabric Phase Sorptive Extraction as an Innovative Multitool for Sample Transfer and Extraction in Pharmacokinetic Analysis Followed by LC-MS Determination of Levofloxacin in Plasma Samples.

Fabric phase sorptive extraction (FPSE) is a simple microextraction technique that allows analytes to be rescued from matrix components while using a small volume of samples to analyze complex biological systems. This study used FPSE as a microextraction tool and a sample storage and transfer device. Levofloxacin as a model molecule was applied intravenously (IV) to New Zealand male rabbits. The samples were simultaneously extracted by using FPSE and protein precipitation methods. The final solutions were analyzed using LC-MS equipped with an ACE C18 LC Column (150 mm × 4.6 mm, 5 μm) at 25 °C employed in isocratic elution mode using solution A (0.1% formic acid in water)/solution B (0.1% formic acid in acetonitrile) (80:20, v/v). The total analysis time was less than 15 min. The developed method was validated using the ICH M10 bioanalytical method validation and study sample analysis guidelines. The results obtained using FPSE were statistically identical to those obtained using protein precipitation. The plasma samples applied onto FPSE (10 μL onto 1.0 cm × 1.0 cm Biofluid Sampler) were stored in three different temperatures [refrigerator (2-8 °C), at ambient temperature (20 ± 5 °C), and in the stability cabinet (40 °C, 75% humidity)] and three different storage conditions (Eppendorf tubes, plastic containers, and straw paper envelopes). Levofloxacin in plasma samples adsorbed by FPSE biofluid sampler remained stable at 2-8 °C in Eppendorf tubes for at least 1 week. This study showed that FPSE could be used as a sample storage and transfer device for pharmacokinetic applications that need to work with small sample volumes and discard aggressive cold chains to store and transfer the plasma samples.

Intrasynovial autograft for reconstruction of chronic large rotator cuff tears in a rabbit model: biomechanical, computed tomography, and histological results

BackgroundRotator cuff (RC) tears are a common cause of shoulder dysfunction and pain, posing significant challenges for orthopedic surgeons. Grafts have been proposed as a solution to augment or bridge torn tendons, but optimal clinical outcomes are not always achieved due to poor graft integration, suboptimal mechanical properties, and immunological reactions. The aim of this study was to investigate the biomechanical, CT and histological results of RC reconstruction using an intrasynovial tendon autograft, in a chronic large tear subscapularis rabbit model.MethodsTwenty-six adult male Zealand white rabbits were used in this study. Large defects in the subscapularis tendons were produced bilaterally in 20 rabbits. After 6 weeks, secondary procedures were performed to the right shoulder of the rabbits, which were reconstructed with an intrasynovial interposition autograft (graft group). The left shoulder did not undergo any further treatment (defect group). The specimens were randomly divided into two equal time groups and underwent biomechanical testing, CT analysis, and histological evaluation at 6, and 12 weeks after reconstruction. In addition, 6 rabbits that were not operated, were used as a control group.ResultsAt 12 weeks post-repair, the graft group exhibited a significant increase in ultimate failure load compared to the defect group (p < 0.05). Furthermore, the 12-week graft group demonstrated comparable stiffness to that of the control group. CT analysis indicated no significant progression of intramuscular fat accumulation in both graft groups, in contrast to the 12-week defect group when compared to the control group. Finally, histological evaluation revealed a gradual integration of the graft with the host tissue at 12 weeks.ConclusionOur study suggests that intrasynovial flexor tendon autografts hold promise as an effective interposition graft for the reconstruction of chronic large RC tears, as they improve the biomechanical and biological properties of the repaired tendon. Nonetheless, further investigations in preclinical large animal models are warranted to validate and extrapolate these findings to human studies.

Allergic reaction of poly-ether-ether-ketone versus titanium implants: A posttest-only control group design experimental study using a rabbit model.

The aim of this study was to determine clinically and genetically the allergic effects of titanium and poly-ether-ether-ketone (PEEK) implants following loading in rabbit tibias. This study included 18 white New Zealand male rabbits (n = 18) divided evenly into three groups: control, titanium (Ti), and PEEK (P). Clinically, the allergenic effect of titanium and PEEK was investigated by detecting the effect on lymph nodes. Furthermore, RT-PCR and ELISA were used to detect the expression of certain genes IL-6, TNF-α, OPG, RANKL, and RUNX-2 through both types of implants. Our findings demonstrated that titanium implants induced enlarged lymph nodes, which PEEK did not. Overall, RT-PCR and ELISA techniques revealed that Ti implants had higher expression of the inflammatory genes IL-6 and TNF-α. Ti had the highest expression in OPG findings, while PEEK had the lowest. RANKL expression was highest in the control group and lowest in the PEEK group. RUNX-2 is the highest for the control group and the lowest for the titanium group. Although titanium implants elicited greater allergy responses than PEEK implants, titanium has the highest expression of bone formation genes and the lowest expression of bone resorption genes, making it preferable to PEEK.