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This study aimed to evaluate the effectiveness of different additives in preventing urolithiasis in lambs fed a diet rich in concentrate and their impact on performance and blood and urinary parameters. Thirty-two noncastrated male lambs, crossbred Dorper × Santa Inês, with initial body weights (BWs) of 23 ± 0.1 kg and ages of 50 ± 5 days, were kept in individual pens and fed a diet composed of 6% Cynodon ssp. hay and 94% concentrate and subjected to four treatments: CON without inclusion of additives, addition of ACL 5 g/kg of dry matter (DM), addition of CCL 6.3 g/kg of DM, and addition of BZA 5 g/kg of DM. There was no effect of treatment or interaction with time on blood parameters (p > 0.050), and performance characteristics, morphometry of ruminal papillae, and scores of cecum and rumen lesions were not affected by the addition of additives to the diet (p > 0.050). Greater urinary acidification was observed in animals from CCL and ACL treatments (p = 0.033). Calcium chloride acidified the urinary pH and can be used instead of ammonium chloride at a concentration of 0.63% based on DM, when this is the objective.

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Mast cell tumour (MCT) is one of the most frequent skin tumours in dogs. Due to their unpredictable biological behaviour, MCTs often cause several therapeutic frustrations, leading to investigation regarding prognostic markers. Lysyl oxidase (LOX) is an enzyme that promotes extracellular matrix stability and contributes to cell migration, angiogenesis and epithelial-mesenchymal transition. Its expression positively correlates with poor prognoses in several human and canine mammary cancers. The aim of this study was to characterise the immunohistochemical expression of LOX in MCT samples and compare it with histological grading and post-surgical survival. Twenty-six tumours were submitted to immunohistochemistry for LOX expression evaluation. All samples were positive for LOX, with variable percentages of cytoplasmic and nuclear positivity. Cytoplasmic positivity was significantly higher in high-grade MCTs (P = .0297). Our results indicate that high expression of cytoplasmic LOX in neoplastic mast cells is an indicator of poor prognosis for canine cutaneous MCTs.

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LIN28 is a RNA-binding protein including two highly conserved homologous, LIN28A and LIN28B. Proto-oncogenes such as LIN28A and LIN28B are generally targeted by the let-7 miRNAs in different types of human cancers. Here, we determined the expression of LIN28A in canine mammary tumor samples and the LIN28/let-7 pathway in canine mammary cell lines. In those cell lines, we identified a functional LIN28/let-7 pathway which exhibited high expression of let-7 members and low expression of its targets, including LIN28A and LIN28B. However, the mammary carcinoma tissue samples showed a frequent expression of LIN28A being expressed mainly in the epithelial cells. No association was observed between LIN28A expression and histopathological classification and grade, TNM and survival time. Our results suggested a possible role of the LIN28A protein in the development of canine mammary carcinomas due to the high frequency observed in the tumor samples (28 of 32). The in vitro experiments suggested that the LIN28/let-7 pathway is active in the tumor cells evaluated. However, more studies are necessary to elucidate the exact role of LIN28/let-7 pathway in canine mammary carcinomas.

LIN28 é uma proteína de ligação ao RNA, com duas formas homólogas altamente conservadas, LIN28A e LIN28B. Os proto-oncogenes LIN28A e LIN28B são regulados pela família de miRNAs let-7 em diferentes tipos de cânceres em humanos. No presente trabalho, o objetivo foi determinar a expressão de LIN28A em amostras de tumor mamário de cadelas e a via LIN28/let-7 em linhagens celulares mamárias caninas. Nestas linhagens, através das técnicas de qPCR e RNAseq, foi identificado que a via LIN28/let-7 apresenta-se funcional, com alta expressão dos membros da família let-7 e baixa expressão de seus alvos, entre eles LIN28A e LIN28B. No entanto, as amostras de tecidos de carcinomas mamários caninos demonstraram expressão frequente de LIN28A, sendo observada principalmente em células epiteliais. Não foram observadas associações entre expressão de LIN28A com classificação e gradação histopatológicas, TNM e tempo de sobrevida. Nossos resultados sugerem uma possível relação da proteína LIN28A no desenvolvimento de carcinomas mamários caninos devido à alta frequência observada nas amostras tumorais (28 de 32). Os experimentos in vitro sugerem que a via LIN28/let-7 é ativa nas linhagens celulares caninas avaliadas. Entretanto, estudos funcionais ainda são necessários para elucidar a função exata da via LIN28/let-7 nos carcinomas mamários caninos.

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PURPOSE: To analyze and compare the reactions at the interface between the composite, composed of fragmented heterologous mineralized bone matrix (MOMHF) and polymethylmethacrylate (PMMA), and the rabbit's tibias, through macroscopic evaluation and scanning electron microscopy (SEM) in different periods. METHODS: In this study, 12 New Zealand adult rabbits were used (E1: n = 3, E2: n = 3, E3: n = 3 and E4: n = 3). They had the right tibial defects filled with composite and were evaluated immediately after surgery and at 30, 60, 90, and 120 days. RESULTS: The composites were incorporated and integrated into the recipient beds in 100% of the cases, defined by the MOMHF osseointegration and the PMMA fibrointegration, with no sign of infection, migration, or rejection. CONCLUSIONS: The behavior of the composites in the recipient beds demonstrates that these biomaterials have the potential to be used in bone defect repairs, offering, thus, better quality of life to the orthopedic patient.

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The use of live animals for educational purposes is an old practice that is still employed in teaching and research institutions. However, there are several objections to this practice, whether for ethical or humanitarian reasons. Surgical techniques teaching using anatomical pieces and/or preserved cadavers promotes greater learning efficiency, provides exercise repetition and increases the confidence and satisfaction of the students when compared to the use of live animals. The current work aimed to analyse the feasibility of using fresh swine urinary bladder and small intestines (jejunum), obtained from slaughterhouses, fixed in 99.8% ethyl alcohol (EA) and preserved in sodium chloride hypersaturated solution (SCHS) at 30%, for 7, 14 and 21 days, as an alternative method for surgical skills training (SST). Swine viscera, fixed in EA and preserved in SCHS, presented a realistic appearance, absence of odour and maintained the viable morphological characteristics during the performance of the operative techniques. Preservation solutions had low cost, were easy to acquire and did not offers risks to human health. Therefore, urinary bladders and small intestines fixed in 99.8% EA for 30 days and maintained in 30% SCHS at different periods were demonstrated as a good viable option as a preservation method for surgical skills training.

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Canine oral melanoma is a common, aggressive tumor with limited treatment options. Tumor-infiltrating lymphocytes (TILs) are important in antitumor immunity. This study used histopathology and immunophenotyping by flow cytometry to evaluate the presence and distribution of TILs in canine oral melanoma, including the frequency of CD8+ T cells, CD4+ T cells, and regulatory T cells. Fifty samples of oral melanoma from 45 dogs that did not receive treatment prior to surgery were included in the study. The distribution of TILs in the tissue (brisk, nonbrisk, and absent) was evaluated in 48 samples. Twenty-eight (58%) samples had a brisk distribution pattern, 10 (21%) samples had a nonbrisk pattern, and 10 (21%) samples had an absent TIL pattern. Comparing the histological evaluation and the immunophenotyping data, it was observed that samples with a brisk TIL pattern had a higher frequency of CD8+ T lymphocytes (P = .05) and a lower frequency of CD4+/CD25+/FoxP3+ Tregs (P = .03), compared to the samples with nonbrisk and absent infiltrate patterns. Patients with a higher survival rate had higher TIL scores (P = .002), a brisk or nonbrisk TIL pattern (P = .001), and an increased frequency of CD8+ T lymphocytes infiltrating the tumor (P = .003). Our analysis suggests that the evaluation of TILs in canine oral melanoma is relevant to predict tumor aggressiveness and patient prognosis.

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The majority of the melanocytic neoplasms are considered malignant and highly metastatic. However, a subset of the melanocytic tumors has a more favorable prognosis and the identification of precise prognostic markers for this neoplasm may be useful to guide treatment. The collagen architecture and density have been shown to correlate with tumor progression in human breast cancer and canine mast cell tumors. The purpose of the present study was to investigate the prognostic value of the intratumoral collagen index (ICI) as an indicator of postsurgical survival and its relation with other prognostic markers for canine oral melanomas (OMs). Twenty-two cases were tested for intratumoral collagen density using Masson's trichrome stain and morphometry. No differences were found between dogs regarding survival. The ICI was not correlated with proliferative activity or nuclear atypia. The results presented herein indicate that the quantity of intratumoral collagen in canine OMs is not an efficient indicator of postsurgical survival. Complementary studies about the expression and activity of enzymes that are capable of degrading extracellular matrix (ECM) components are necessary.

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ABSTRACT Purpose To analyze and compare the reactions at the interface between the composite, composed of fragmented heterologous mineralized bone matrix (MOMHF) and polymethylmethacrylate (PMMA), and the rabbit's tibias, through macroscopic evaluation and scanning electron microscopy (SEM) in different periods. Methods In this study, 12 New Zealand adult rabbits were used (E1: n = 3, E2: n = 3, E3: n = 3 and E4: n = 3). They had the right tibial defects filled with composite and were evaluated immediately after surgery and at 30, 60, 90, and 120 days. Results The composites were incorporated and integrated into the recipient beds in 100% of the cases, defined by the MOMHF osseointegration and the PMMA fibrointegration, with no sign of infection, migration, or rejection. Conclusions The behavior of the composites in the recipient beds demonstrates that these biomaterials have the potential to be used in bone defect repairs, offering, thus, better quality of life to the orthopedic patient.

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Background: Sinus neoplasms are reported as low frequency in horses. Its clinical characteristics are often nonspecific, depend on complementary methods for diagnosis, and when diagnosed, generally they are already advanced, limiting therapeutic possibilities. The objective of this case series was to detail clinical aspects and complementary exams for sinus neoplasms for early diagnosis, comparing them with the literature. Cases: Four horses were treated at the College of Veterinary Medicine and Animal Science of the University of São Paulo, with different clinical signs and previous diagnoses, which when evaluated by respiratory endoscopy, radiography, oral cavity evaluation and histopathological exams, revealed the diagnosis of anaplastic carcinoma, poorly differentiated carcinoma, ossifying fibroma and lymphoma. Previous diagnosis, based mainly on clinical signs, were sinusitis secondary to apical infection, ethmoidal hematoma, sinus cyst and sinusitis secondary to periapical disease. The cases of anaplastic carcinoma (case 1) and lymphoma (case 4) presented with an advanced degree of the disease with involvement and destruction of paranasal structures and adjacent tissues, in addition to a poor general condition, which made surgical treatment impossible and led to euthanasia. In these cases, previous treatment was made to apical infection and periodontal disease with secondary sinusitis, but negative evolution led to suspicion of neoplasia, confirmed by histopathological exam of incisional biopsy of the mass in oral cavity. Benign ossifying fibroma (case 3) presented with progressive respiratory difficulty due to occlusion of the lumen of some nasal meatus and radiographic signs of invasion and deformation of the adjacent bones, it was submitted for surgical excision and there was no recurrence until hospital discharge. The poorly differentiated carcinoma (case 2) was a multilobulate neoformation in the ethmoidal region, similar to ethmoid hematoma in endoscopic and radiographic evaluation, it was submitted for excision and two sessions of electrochemotherapy with bleomycin, associated with administration of piroxicam, which obtained a good result until the period of 1 year after discharge. Discussion: It was found that many characteristics are common with these types of neoplasms, and the clinical signs, such as nasal secretions, airway obstruction, increased facial volume, severe alterations in oral cavity, although unspecific, suggest the differential diagnosis for neoplasms. It is important to differentiate from other diseases noting the evolution and growth of these tumors, like in cases 1 and 4, especially the growth to internal tissues, using complementary methods described here, like endoscopic and radiographic examination. Late identification or even manipulation of neoplasms, without proper diagnosis, leads to a few prognoses regarding life. When it is possible to perform surgical excision, complementary methods are important to guide the procedure, and definitive diagnosis is made through histopathologic exam and some need immunohistochemistry analysis. Cases 2 and 3 had surgical access, were submitted to excision and treatment with good results, both with close monitoring in first months and prolonged quality of life. These results highlight the importance of complementary methods for early diagnosis, correct intervention and monitoring of evolution.

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Background: Equines are routinely subjected to enucleation due to palpebral tumors. Blepharoplasties in horses, especially in the lower eyelid, are rarely performed due to the difficulty of sliding once the tissue around the eyes presents low mobility. Defects involving more than 50% of the lower eyelid is considered challenging after tumor removal. Squamous cell carcinoma (SCC) is the second most reported neoplasm in horses, being very common in regions of the lower eyelid, third eyelid, sclera and or cornea. The aim of this study is to present the Destro VY skin advancement flap as a blepharoplasty technique performed after surgical excision of a SCC, with total commitment of the lower eyelid, completely covering the right eye of a mare. Case: A 8-year-old mare Paint Horse, weighing 420 kg, was referred for evaluation of tumor tissue of 6.0 x 4.0 x 2.0 cm, with nodular and ulcerated appearance, involving the right lower eyelid, in its total extension and completely covering the eye, without adhering to it. Considering the initial suspicion of SCC, the treatment strategy performed was surgical eyelid excision and maintenance of the eye, followed by blepharoplasty as an attempt to reconstruct the eyelid. Under general inhalation anesthesia, the animal was placed in left lateral recumbency, when the surgical region was prepared and local anesthetic block was performed. After antisepsis, a skin incision was made circumscribing the tumor, respecting a margin of 10 mm apart and excision of all visible tumor tissue was performed followed by intralesional ozone therapy. Blepharoplasty was performed to cover the portions of the exposed lacrimal and zygomatic bones, as well as correction of the eyelid aesthetics. For this, Destro VY skin advancement flap was performed for reconstruction of the lower eyelid. An incision of approximately 7 cm in Vshaped skin was performed, and the subcutaneous tissue under the V was dissected, maintaining a central pedicle, responsible for the vascularization of the flap, which was slid, approximately 20 mm, towards the eye. After obtaining the desired skin approximation, Y-suture was performed, covering the exposed bone and reconstructing the lower eyelid. In the postoperative period, local instillation of mitomycin eye drops and systemic meloxicam administration were instituted. The mare had her vision restored, presenting satisfactory morpho functional and aesthetic results and no tumor recurrence during 1-year of follow-up. Discussion: The repair of lower eyelid imperfections is challenging, especially when they have large defects, and there are no reports of performing the Destro VY skin advancement flap technique in horses for lower eyelid reconstruction. In this case, the importance of the blepharoplasty technique is emphasized, avoiding enucleation, preserving horse's vision and aesthetics. In addition, aiming to avoid tumor recurrence, especially if surgical safety margins can not be achieved, other complementary treatments should be associated, including intralesional ozone therapy, mitomycin, an antineoplastic chemotherapy drug, and meloxicam, a COX-2 selective, non-steroidal anti-inflammatory drug, as performed in this study. It is concluded that the use of the Destro VY skin advancement flap technique for reconstruction of the external lamella in cases of SCC in the lower eyelid of horses is a feasible technique, which preserves the animal's vision, as well as aesthetics. The safety margin in the surgical excision of the SCC and the association of complementary therapies in the resolution of the condition are important points also to be considered.

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