Radiologic and computed tomography evaluation of the beaks from three bird species.

This study aimed to evaluate the beaks of three species of birds using radiography and computed tomography (CT). The mean lengths of maxillary and mandibular rostra on radiographs were highest for toco toucan, followed by buff-necked ibis, and least for red-legged seriema birds. The height and width of maxillary and mandibular rostra measured on CT had mean values highest for toco toucans, followed by red-legged seriema, and least for buff-necked ibis. Except for the proximal region of the maxillary rostrum, the HU values were positive for other regions of the maxillary and mandibular rostra in the buff-necked ibis and red-legged seriema and negative in all for the toco toucan.

Sonographic features of abdominal organs in healthy captive Neotropical otters (Lontra longicaudis).

This study aimed to assess the sonographic features of abdominal organs in healthy captive Neotropical otters (Lontra longicaudis). The sonograph showed that the urinary bladder was located in the caudal abdomen and its content was uniformly anechoic. The bladder wall had three layers: outer hyperechoic serosa, hypoechoic muscular layer and hyperechoic mucosa. The mean total wall thickness was 0.10 cm. The splenic parenchyma had a homogeneous echotexture with greater echogenicity than that of the left renal cortex and liver. The borders were regular and tapered. Rugal folds were observed in the stomach when undistended. The mean gastric wall thickness was 0.28 cm and five distinct layers were visible. The liver had smooth contours, and division of the hepatic lobes was not precisely visualized. The hepatic parenchyma had a homogeneous echotexture with greater echogenicity as compared to the right kidney and lesser echogenicity than that of the spleen. The gallbladder appeared as an oval or rounded structure in the transverse plane, filled with homogeneous anechogenic content; the wall was thin, regular and hyperechoic, with a mean thickness of 0.09 cm. The kidneys had a lobulated appearance with renicular subunits. The mean total length of the kidneys in longitudinal plane was 6.18 cm for the left and 6.27 cm for the right. Each reniculus was covered by an echogenic capsule, and the medullary region was more hypoechogenic than the cortical region. In conclusion, sonographic features in most of the abdominal organs in Neotropical otters are similar to the ultrasound patterns observed in healthy dogs and cats, except for kidneys with reniculi.

Radiographic and sonographic features, and histogram parameters of the liver and spleen in healthy Toco toucans (Ramphastos toco, Müller 1976).

This study aimed to evaluate radiographic and sonographic features, and histogram parameters based on grayscale ultrasound of the liver and spleen in healthy toco toucans. Fifteen adult toco toucans (Ramphastos toco), seven females and eight males, weighing approximately 650 g, were enrolled in the study. On the right lateral radiographic view, the liver was visualized in the midventral region of the coelomic cavity; ultrasonographically, the liver was located in the middle portion of the coelomic cavity in close relationship to the heart, and thoracic and abdominal air sacs. Two hepatic lobes were identified; the right lobe was larger than the left one. The spleen was visualized in 10 toco toucans on radiographs and only in eight toucans on ultrasound exams. The gallbladder was identified only on ultrasound. On the right lateral radiographic view, the spleen was visualized dorsal to the proventriculus and ventral to the lungs/air sacs as an oval shape. Ultrasonographically, the spleen was observed caudal to the liver, cranial to the proventriculus and craniodorsal to the ventriculus. There was no significant difference in spleen length for either radiographic or ultrasound measurements. The brightness intensity (BI) for mean gray level (G) and standard deviation of gray levels (SG ) in the liver were 101.315 (± 16.170) and 12.453 (± 2.616), respectively. Mean G and SG levels in the spleen were 63.940 (± 18.321) and 7.494 (± 3.595), respectively. In conclusion, the sonographic features and histogram parameters indicated that the liver is more echogenic and heterogeneous than the spleen, which must be considered for diagnosing alterations in these organs.

Ultrasonographic evaluation of the liver and gallbladder and hepatic histogram of non-venomous snakes.

This study aimed to describe sonographic features of the liver, gallbladder and hepatic histogram from grey-scale ultrasound in three species of healthy non-venomous snakes. Twenty-eight adult snakes were enrolled in the study, including 10 common boas (Boa constrictor), eight black-tailed pythons (Python molurus) and 10 rainbow boas (Epicrates crassus). The snakes fasted for 30 days and were manually restrained while conscious. For B. constrictor and P. molurus the liver and gallbladder were best visualized in ventral recumbency, and E. crassus in dorsal recumbency. A single elongated hepatic lobe was identified in all snakes. The gallbladder was positioned caudal and separated from the liver, with an oval shape and homogeneous anechoic content in the lumen, and thin and regular walls. A region of interest by pixel number was chosen for the liver, fat bodies, left kidney, and splenopancreas. The mean grey level (G) of the organs had significant differences within each species. Standard deviation of grey levels (SG ) had significant differences within B. constrictor and E. crassus. P. molurus had no significant difference among organs. The comparison among snakes showed that E. crassus had G of liver and splenopancreas lower than B. constrictor and P. molurus. The SG of the liver in E. crassus was lowest compared to B. constrictor and P. molurus. P. molurus showed the highest values in mean of G and SG . In conclusion, despite the liver and gallbladder having similar sonographic features, the grey-level histogram showed that liver echotexture and echogenicity differ among species.

Long-Term Effects of Whole-Body Vibration on Hind Limb Muscles, Gait and Pain in Lame Dogs with Borderline-to-Severe Hip Dysplasia-A Pilot Study.

This pilot study aimed to evaluate the long-term effects of Whole-Body Vibration (WBV) on hind limb muscles, gait and pain in lame dogs with borderline-to-severe hip dysplasia. Ten lame client-owned dogs with borderline-to-severe hip dysplasia, aged from 1.5 to 9.0 years and weighing 14.5 to 53.0 kg, were enrolled. The WBV training program consisted of 15 min sessions three times weekly for 16 weeks. Muscles of the hind limbs were evaluated using measurements of thigh circumference, the cross-sectional thickness of selected hind limb muscles by ultrasound assessment, and vastus lateralis muscle activity determined by surface electromyography (EMG). Lameness and clinical signs of pain were assessed by visual lameness scoring, orthopedic examination and an owner-based questionnaire. Kinetic analysis was performed by using a pressure-sensitive walkway. Manual thigh circumference measurements of both hind limbs showed significant increases over the trial period with a greater degree of change observed after week 8. Ultrasound measurements of the left gluteal muscles and the quadriceps femoris muscles of both hind limbs showed significant increases in the cross-section thickness post WBV. Owner's perception of pain also showed a decrease in signs of pain at week 12 and week 16 compared to baseline. Based on graphs of the EMG activity patterns of the vastus lateralis muscle, 65% of the hind limbs had an improvement after 48 WBV sessions when compared to pre-session patterns. However, no significant differences were observed in visual lameness evaluation and kinetic analysis. Therefore, further studies will help to better clarify the role of WBV in canine rehabilitation protocols.

Induced membrane technique using bone cement with or without cefazolin in chicken segmental radius defect.

The utilization of antibiotic-loaded cement spacer in the induced membrane development has been a debate topic in human medicine. To the best of the author's knowledge, these combinations have not yet been evaluated in birds. Therefore, this study assessed induced membrane formation using radiography and histology, in a segmental defect of a chicken radius, with or without the addition of cefazolin. Thirty 18-month-old healthy chickens were divided into two equal groups: G1-bone defect filled with bone cement; G2-bone defect filled with cefazolin powder-loaded bone cement. Radiographic examinations of the left forearm were taken immediately after surgery and at 7, 15, and 21 postoperative days. For the collection of the induced membranes, five chickens in each group were euthanized at 7, 15, and 21 days after surgery. Radiographically, the bone cement was identified as a radiopaque structure occupying the bone defect in both groups. Mild new bone formation in at least one of the fractured extremities of the bone defect was seen only 21 days after surgery in most chickens. Histologically, there was no difference in the mean thickness of the induced membrane between groups at all time points. Multifocal multinucleated cells differed between groups at 7 (G1 > G2) and 21 (G2 > G1) days after surgery. Mononuclear inflammatory infiltrate differed between groups only on day 21 (G1 > G2). Fibrous tissue proliferation did not differ between groups at all evaluation times. Blood vessel density differed only at 21 days postoperatively (G2 < G1). Multifocal areas of cartilage differed between groups at all time points (G1 > G2). In conclusion, cefazolin mixed with bone cement did not affect thickness of the induced membrane, but did result in a negative effect on some histological aspects, such as fewer vessels, less multifocal areas of cartilage, and persistence of inflammation.

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

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

Myeloperoxidase enzyme and Ferric-reducing antioxidant power concentrations in lean and obese dogs.

The study aimed to assess plasma Myeloperoxidase enzyme (MPO) and Ferric-reducing antioxidant power (FRAP) in obese dogs and compare them with ideal body weight dogs. Thirty-two dogs were distributed into two groups according to a 9-point body condition score (BCS), as follows: Control group (n = 16), dogs with a BCS of 4 or 5; Obese group (n = 16), dogs with a BCS of 8 or 9. Plasma MPO and FRAP assays, neutrophil count, lipid profile (cholesterol and triglycerides), and systolic blood pressure (SBP) were evaluated in both groups. The duration of obesity was defined based on history. The obese group showed higher values for body weight, BCS, SBP, neutrophil count, triglycerides, and MPO than the Control group. A positive correlation was observed between MPO concentrations and BCS and body weight. FRAP concentrations showed a positive correlation with the duration of obesity. The results suggested that an inflammatory state caused by obesity may promote increased neutrophil count and MPO concentrations, besides the positive correlation between MPO with BCS and body weight. The obesity in dogs promoted slight active MPO elevation, influenced by body weight, BCS, and neutrophil count. The FRAP assay did not show the expected reduction and, therefore, needs further investigation.

Prevalence of cholelithiasis in lion tamarins (Leontopithecus spp.) kept under human care by using abdominal ultrasound.

BACKGROUND: Cholelithiasis is a digestive system disorder of multifactorial origin that occurs due to stones formed in the gallbladder. This study aimed at investigating by abdominal ultrasound examination the prevalence of cholelithiasis in lion tamarins kept under human care. METHODS: Thirty lion tamarins from five Brazilian zoos, including 17 golden lion tamarins and 13 golden-headed lion tamarins, were evaluated. RESULTS: Considering all lion tamarins, the overall frequency of cholelithiasis was 53.3% (16/30). There were no significant differences between species and sex. Cholelithiasis was predominant (75.0%) in lion tamarins older than 5 years. Septate gallbladder was observed in 86.6% (26/30) of the lion tamarins. Of these, 53.8% (14/26) had gallstones. Biochemical analysis revealed a moderate positive correlation between gamma-glutamyl transferase and the number of gallstones. CONCLUSIONS: Asymptomatic cholelithiasis is frequent in lion tamarins kept under human care. Therefore, systematic monitoring through ultrasound should be part of the preventive care of these animals.

Threats to health and conservation of free-living sloths (Bradypus and Choloepus) under anthropic influence in the city of Manaus, Amazonas state, Brazil / Ameaças à saúde e conservação de preguiças (Bradypus e Choloepus) de vida livre sob influência antrópica em Manaus, Estado do Amazonas, Brasil

Abstract Anthropogenic disturbances affecting forest areas can increase disease prevalence and susceptibility in several species of arboreal mammals, such as sloths. Thus, this study aimed to evaluate the most common conditions in body systems of free-ranging sloths admitted at the Wildlife Triage and Rehabilitation Center of Amazonas of the Institute of Environment and Renewable Natural Resources. A total of 227 individuals (139 retrospective cases from 2015 to 2019, and 88 prospective cases from July 2020 to July 2021) were evaluated over a six-year period. Cases from the genus Bradypus showed involvement of the following body systems: 44% respiratory, 29% integumentary, 15% musculoskeletal, 5% digestive, 3% visual, 2% auditory, 1% circulatory and 1% genitourinary, while that distribution in the genus Choloepus was: 39% musculoskeletal, 27% integumentary, 19% respiratory, 9% digestive, 3% circulatory, 1% visual, 1% auditory and 1% genitourinary. The results reveal significant differences between the condition detected and the genus (Bradypus and Choloepus), age and case outcome. These results can provide data for future investigations of sloth diseases, confirming lesions, as well as motivating and suggesting adequate management methods.

Resumo Distúrbios antrópicos que afetam áreas florestais podem aumentar a prevalência de afecções e a suscetibilidade às doenças em diversas espécies de mamíferos arborícolas, como as preguiças. Desta forma, este estudo teve como objetivo avaliar as condições mais comuns nos sistemas orgânicos de preguiças de vida livre admitidas no Centro de Triagem e Reabilitação de Animais Silvestres do Amazonas. Um total de 227 indivíduos (139 casos retrospectivos de 2015 a 2019 e 88 casos prospectivos de julho de 2020 a julho de 2021) foram avaliados durante um período de seis anos. Para o gênero Bradypus foram diagnosticadas 44% de afecções do sistema respiratório, 29% tegumentar, 15% musculoesquelético, 5% digestório, 3% visual, 2% auditivo, 1% circulatório e 1% genitourinário. Por sua vez, para o gênero Choloepus foram detectadas 39% de afecções do sistema musculoesquelético, 27% tegumentar, 19% do sistema respiratório, 19% do sistema respiratório, 9% digestório, 3% circulatório, 1% visual, 1% auditivo e 1% genitourinário. Os resultados mostraram diferenças significativas na prevalência da afecção e gênero das preguiças (Bradypus e Choloepus), a faixa etária e desfecho do caso. Esses resultados podem fornecer subsídios para investigar as doenças de preguiças, confirmando afecções, motivo e sugerir métodos adequados de manejo.

Evaluation of the degradation of two bioabsorbable interference screws: an in-vivo study in sheep.

PURPOSE: To evaluate in-vivo degradation of two bioabsorbable interference screws. METHODS: Twenty-two crossbred Santa Inês ewes were used. A poly-DL-lactide (PDLLA) screw (70%/30%) was inserted in the right pelvic limb, and a PDLLA screw (70%) + ß-tri-calcium phosphate (ß-TCP) (30%) in the left pelvic limb. Animals were euthanized at one, four, seven and a half and 18 months after surgery. Plain radiography, computed tomography (CT), microCT, and histological analysis were accomplished. RESULTS: PDLLA screw was hypodense at all evaluation moments, but with progressive density increase along the central axis, whereas PDLLA/ß-TCP was initially hyperdense and progressively lost this characteristic. No adverse reactions were observed on histological evaluation. CONCLUSIONS: The inclusion of ß-TCP favors screw degradation since the PDLLA/ß-TCP screws evidenced a more intense degradation process than the PDLLA screws at the last evaluation. PDLLA screws showed higher bone production, evident around the screw thread, inside the lateral perforations, and in the central canal, whereas the PDLLA/ß-TCP screws presented less bone tissue at the implantation site.

Are echocardiographic parameters affected by body condition scores in blue-fronted Amazon parrots (Amazona aestiva, Linnaeus, 1758)?

This study aimed to determine the echocardiographic parameters of blue-fronted Amazon parrots (Amazona aestiva, Linnaeus, 1758) with varying body condition scores. Thirty-five birds only grown in captivity were included in the study and allocated into three different groups according to their respective body condition scores: Lean, Ideal, and Obese. The group of obese parrots presented lower right ventricle dimensions in diastole than lean parrots. The fractional shortening was considerably lower in obese parrots than in parrots with lean and ideal body condition scores but without statistical significance. The flow rate and the aortic pressure gradient were lower in the lean group than in the ideal group. The alterations in the nutritional state of captive blue-fronted amazon parrots may lead to cardiovascular dysfunctions detected through an echocardiographic evaluation, which represents an important diagnostic tool for these animals. The description of the techniques and the measures obtained in this study can contribute to future research in the area.

Qualitative and quantitative evaluation of the ventricular system and brain parenchyma in healthy dogs of different skull conformation on computed tomography scans.

This study aimed to perform quantitative and qualitative evaluations of the lateral and third ventricles, and brain parenchyma, in healthy dogs of different skull conformations on CT scans. Forty-five adult client-owned dogs were divided into three groups according to skull conformation: G1 (dolichocephalic)-15 German Shepherds; G2 (mesaticephalic)-15 Rottweilers; G3 (brachycephalic)-15 Boxers. Transverse plane images were used for quantitative and qualitative evaluations of the lateral ventricles and third ventricle, and pre- and post-contrast brain parenchyma. The height of both ventricles and brain was measured at the level of the interthalamic adhesion. Ventricle height, brain height, and ventricle/brain height ratio were statistically higher in G3 compared with G1 and G2 that were similar. The third ventricle was visible but unmeasurable in five dogs from G1 and three from G2. In G3, all dogs had third ventricle visible and measurable in all images. Asymmetric ventricles were seen in five dogs in Group 1 and Group 2, and seven in Group 3. Brain parenchyma had homogenous density in 80% of the dogs in all groups. Contrast enhancement of the rostral midline was visualized in all dogs. In conclusion, brain CT scans of healthy dogs showed that the qualitative data were similar among groups, but lateral ventricle and brain measurements in brachycephalic dogs differed from the dolichocephalic and mesaticephalic dogs.

Use of hyaluronic acid associated with triamcinolone acetonide or ozone gas in the treatment of induced osteoarthritis in rabbits.

PURPOSE: To evaluate the effects of the intra-articular application of hyaluronic acid associated with triamcinolone acetonide, and ozone gas in the treatment of induced osteoarthritis in rabbit's stifles. METHODS: Twenty-one Norfolk rabbits were submitted to cranial cruciate ligament transection of the left stifle. After six weeks of the surgery, the rabbits were randomized assigned into three groups: G1 (control) - saline solution (0.9%); G2 - hyaluronic acid associated with triamcinolone; G3 - ozone gas, submitted to three intra-articular applications every seven days. RESULTS: Significant differences occurred: osteophytes at medial femoral condyle (G2 > G1, G2 > G3) on radiography exam; thickening of the medial condyle (G1 > G3, G2 > G3) on ultrasound exam; osteophytes at lateral tibial condyle (G2 > G1, G2 > G3), and medial femoral condyle (G1 > G2, G3 > G1) on computed tomography. Histologically, mean values of chondrocytes in the femur and tibia in G3 and G2 were statistically lower. CONCLUSIONS: The intra-articular injection of hyaluronic acid associated with triamcinolone accentuated degenerative joint disease by imaging and macroscopic evaluations, and by histological findings, this treatment and the ozone gas treatment showed similar effects and were inferior to the saline solution (0.9%).

Effect of low-level laser therapy on the membrane induced by the Masquelet technique at an orthotopic site in rabbits.

PURPOSE: To evaluate the low-level laser therapy (LLLT) on the membrane induced by the Masquelet technique in rabbits. METHODS: Twelve Norfolk rabbits at approximately 3 months of age were used. A 1-cm segmental defect was induced in both radii, which were filled with polymethylmethacrylate cylinder. LLLT was used postoperatively in the bone defect of one of the forelimbs every 48 hours for 15 days. Six rabbits were euthanatized on third and sixth postoperative weeks. RESULTS: In both forelimbs, radiographs showed new bone growth from radius cut ends on the third postoperative week and more advanced stage on the sixth postoperative week. Ultrasound showed induced membrane one week after the surgery. Histologically, there were no significant differences in the semi-quantitative score of inflammation intensity, total number of blood vessels, bone metaplasia, and collagen. The average thicknesses were 2,050.17 and 1,451.96 µm for control membranes and 2,724.26 and 2,081.03 µm for irradiated membranes, respectively, on third and sixth postoperative weeks. Vascular endothelial growth factor A (VEGF-A) and platelet derived growth factor (PDGF) expression were present in the induced membranes of control and irradiated forelimbs, but there was no significant difference. CONCLUSIONS: Based on assessment methods, it was not possible to demonstrate the effect of LLLT on the induced membrane.

Ultrasonography of the gastrointestinal tract of toco toucans (Ramphastos toco).

Baseline data for wall thickness in healthy toucans can be used to diagnose disease in sick individuals. This study aimed to evaluate the use of ultrasonography for the examination of the gastrointestinal tract of healthy toco toucans (Ramphastos toco). Ten non-anaesthetized healthy adult toco toucans were evaluated. Food was withheld for 3 h prior to the ultrasound examination. Longitudinal and transverse images of the gastrointestinal tract were obtained using ventromedian cranial and ventromedian caudal approaches to evaluate the morphology and stratification. The wall thickness of the sections was measured: proventriculus and ventriculus, duodenum, jejunum/ileum, and cloaca. Additionally, the thickness of the mucosal layer of the duodenum and jejunum/ileum was also measured. Subsequently, the ratios of the duodenal wall thickness to the duodenal mucosa layer and the total wall thickness of the jejunum/ileum to the jejunum/ileum layer mucosa were stablished. The wall thickness of the proventriculus was significantly higher than the wall thickness of ventriculus. The wall thickness of the duodenum was significantly higher than the wall thickness of jejunum/ileum. The mean ratios of the duodenal wall thickness to the duodenal mucosa layer and the wall thickness of the jejunum/ileum to the jejunum/ileum layer were 83.15% and 80.07%, respectively. In conclusion, it was possible to assess the stomach and intestines using ultrasound examination in healthy toco toucans, due to their medium body size and no interference by surrounding air sacs.

Chronic pain and gait analysis in dogs with degenerative hip joint disease treated with repeated intra-articular injections of platelet-rich plasma or allogeneic adipose-derived stem cells.

This prospective, comparative, randomized, horizontal, and double-blind clinical study investigated the clinical efficacy of leucocyte-poor platelet-rich plasma (PRP, n=8) or allogeneic adipose-derived stem cells (ADSC, n=8) in dogs with bilateral degenerative hip joint disease (DHJD). Sixteen dogs were treated with two intra-articular injections of PRP or ADSCs, within a 30-day interval. The Canine Brief Pain Inventory (CBPI), the Helsinki Chronic Pain Index (HCPI), and Visual Analogue Scales for pain (VAS-pain) and locomotion (VAS-loc) were assessed by the dog owners. Analysis-of-gait using a force plate, response to palpation (VAS-palp), and the descriptive numerical scale for pain (DNS) were measured by a veterinarian. The assessments were performed before (baseline), 30 and 60 days after the first treatment. Data were analyzed using the unpaired t test, paired Wilcoxon test, Fisher's exact test, and Mann-Whitney and Friedman tests (P<0.05). Compared with baseline HCPI, CBPI, VAS-pain, and VAS-palp scores reduced 41%, 52%, 51%, and 48% (P=0.0001-0.03) at 60 days in the ADSC group. In PRP-treated dogs, CBPI, VAS-loc, and DNS scores decreased by 43%, 43%, and 33% at 60 days, respectively (P=0.0003-0.011). Based on CBPI data, the rate of success at 60 days was 75% and 25% in the ADSC and PRP groups (P=0.13), respectively. Both therapies were apparently safe and effective to reduce chronic pain in dogs with bilateral DHJD during a 60-day period. However, a trend towards greater improvement was provided by the ADSC treatment.

Preparation and characterization of leukocyte- and platelet-rich fibrin membrane derived from cats' blood.

Autologous platelet concentrates have been used in regenerative medicine in humans due to the abundance of growth factors, but there are only a few reports in small animals. This study aimed to prepare and characterize a leukocyte and platelet-rich fibrin membrane (L-PRF) produced with blood obtained from cats. Thirteen client-owned healthy adult Maine Coon cats were enrolled. The blood samples were collected and centrifuged at 650g for 12 min using a centrifuge specifically designed for this application. The L-PRF clot was removed from the tube and red blood cell base layer was separated, leaving buffy coat intact. After this, L-PRF clot was compressed by specialized metal plate for 30-60 s, and L-PRF membrane was obtained. Light microscopy examination of the membranes showed three distinct layers: white part, buffy coat, and red part. Immunohistochemical analysis demonstrated expression of vascular endothelial growth factor and platelet derived growth factor. The scanning electron microscopy showed that three-dimensional architecture of fibrin network was more compact in the area near the buffy coat. In conclusion, the method used allowed the characterization of the L-PRF membrane composition, which presented cell types and fibrin network architecture similar to those described in the human species.

Use of hyaluronic acid associated with triamcinolone acetonide or ozone gas in the treatment of induced osteoarthritis in rabbits

Purpose: To evaluate the effects of the intra-articular application of hyaluronic acid associated with triamcinolone acetonide, and ozone gas in the treatment of induced osteoarthritis in rabbit’s stifles.Methods: Twenty-one Norfolk rabbits were submitted to cranial cruciate ligament transection of the left stifle. After six weeks of the surgery, the rabbits were randomized assigned into three groups: G1 (control) – saline solution (0.9%); G2 – hyaluronic acid associated with triamcinolone; G3 – ozone gas, submitted to three intra-articular applications every seven days. Results: Significant differences occurred: osteophytes at medial femoral condyle (G2 > G1, G2 > G3) on radiography exam; thickening of the medial condyle (G1 > G3, G2 > G3) on ultrasound exam; osteophytes at lateral tibial condyle (G2 > G1, G2 > G3), and medial femoral condyle (G1 > G2, G3 > G1) on computed tomography. Histologically, mean values of chondrocytes in the femur and tibia in G3 and G2 were statistically lower. Conclusions: The intra-articular injection of hyaluronic acid associated with triamcinolone accentuated degenerative joint disease by imaging and macroscopic evaluations, and by histological findings, this treatment and the ozone gas treatment showed similar effects and were inferior to the saline solution (0.9%).

Effect of low-level laser therapy on the membrane induced by the Masquelet technique at an orthotopic site in rabbits

ABSTRACT Purpose: To evaluate the low-level laser therapy (LLLT) on the membrane induced by the Masquelet technique in rabbits. Methods: Twelve Norfolk rabbits at approximately 3 months of age were used. A 1-cm segmental defect was induced in both radii, which were filled with polymethylmethacrylate cylinder. LLLT was used postoperatively in the bone defect of one of the forelimbs every 48 hours for 15 days. Six rabbits were euthanatized on third and sixth postoperative weeks. Results: In both forelimbs, radiographs showed new bone growth from radius cut ends on the third postoperative week and more advanced stage on the sixth postoperative week. Ultrasound showed induced membrane one week after the surgery. Histologically, there were no significant differences in the semi-quantitative score of inflammation intensity, total number of blood vessels, bone metaplasia, and collagen. The average thicknesses were 2,050.17 and 1,451.96 μm for control membranes and 2,724.26 and 2,081.03 μm for irradiated membranes, respectively, on third and sixth postoperative weeks. Vascular endothelial growth factor A (VEGF-A) and platelet derived growth factor (PDGF) expression were present in the induced membranes of control and irradiated forelimbs, but there was no significant difference. Conclusions: Based on assessment methods, it was not possible to demonstrate the effect of LLLT on the induced membrane.