Relação espacial entre o estojo córneo e a falange distal em éguas Campolina adultas com e sem obesidade / Spatial relationship between the hoof capsule and the distal phalanx in adult Campolina mares with and without obesity

A laminite endocrinopática tem acometido um número crescente de equinos com sinais de obesidade. Em um estudo recente com fêmeas jovens (até cinco anos) da raça Campolina, demonstraram-se indícios de alterações no dígito, ainda discretas, aparentemente associadas ao aumento da adiposidade. Com a hipótese de que essa associação é mais evidente em animais em faixa etária superior, o objetivo do presente estudo foi estudar éguas adultas (acima de cinco anos) da raça Campolina com e sem obesidade, avaliando-se radiograficamente a relação espacial entre estojo córneo e falange distal. Foram utilizadas 27 éguas entre seis e 14 anos de idade, sendo analisadas variáveis de adiposidade e medidas radiográficas dos cascos dos membros torácicos de equinos com escore corporal de 5 a 7/9 (grupo controle) e de 8 a 9 (grupo obeso). Foram feitas comparações entre os grupos e correlacionaram-se as variáveis de adiposidade com variáveis casco. A distância de afundamento da falange distal foi cerca de 20% superior nas éguas obesas (12,3±2,5 contra 10,2±2,2mm no grupo controle). Esse parâmetro também correlacionou (P<0,01) com vários parâmetros de adiposidade, com destaque para o escore de condição corporal (r=0,47) e a circunferência de pescoço a 75% (r=0,42). Os resultados corroboram estudos prévios que demonstraram associação entre obesidade e indícios de separação entre falange distal e estojo córneo em equinos de raças nacionais, comprovando, assim, a utilidade da avaliação radiográfica nesses animais. Em conclusão, éguas da raça Campolina com obesidade possuem alterações evidentes na relação espacial entre estojo córneo e falange distal, que se intensificam com o aumento da idade e da adiposidade.(AU)

In a recent study with young females (up to 5 years old) of the Campolina breed, there were discrete indications of alterations in the digit, apparently associated to the increase in adiposity. With the hypothesis that this association is more evident in horses in the upper age group, the objective was to study Campolina adult mares (above 5 years) with and without obesity, evaluating radiographically the spatial relationship between the horn and distal phalanx. Eighteen mares between six and fourteen years and with a body score of 5 to 7/9 (Control Group) and 8 to 9 (Obeso Group) were used. Adiposity and radiographic measurements from the forelimbs were analyzed. Comparisons were made between groups and adiposity variables were correlated with hoof variables. The sinking distance of the distal phalanx was about 20% higher in obese mares (12.3±2.5 versus 10.2±2.2mm). This parameter also correlated (P< 0.01) with several adiposity parameters, with emphasis on body score condition (r= 0.47) and neck circumference at 75% (r= 0.42). In conclusion, Campolina mares with obesity have obvious alterations in the spatial relation between the corneal and the distal phalanx, which get intense according to increases in age and adiposity.(AU)

Histological and immunohistochemical evaluation of two cell therapy protocols in equine suspensory ligament repair / Avaliação histológica e imunoistoquímica do reparo do ligamento suspensório equino tratado com dois protocolos de terapia celular

This study aimed to histologically evaluate the quality of tissue repair in equine suspensory ligament treated with two cell therapy protocols. All four limbs of six animals were operated simultaneously to remove a fragment in each ligament using a skin biopsy punch. Two days later, intralesional injections were performed using bone marrow mononuclear fraction (BM group), cultivated cells derived from adipose tissue (AT group), saline (positive control group), or no treatment (negative control group), in such way that each horse received all treatments. After sixty days biopsies were performed for histological analysis (H & E, Masson's trichrome and picrosirius red) and immunohistochemistry analysis (collagen type III). Histological findings (H & E and Masson's trichrome), birefringence intensity (through picrosirius) and collagen type III expression (through immunohistochemistry) were analyzed. Samples from treated groups had better birefringence intensity (P=0.007) and fiber alignment scores were superior compared to controls, though not statistically significant (P=0.08). Presence of inflammatory cells and intense staining for collagen type III occurred in all groups demonstrating an active healing process. In conclusion, both protocols resulted in improvement of tissue repair indicating their potential to be used as an adjuvant treatment of equine suspensory ligament disorders.(AU)

Este estudo teve como objetivo a avaliação histológica e imunoistoquímica do reparo do ligamento suspensório equino tratado com dois protocolos de terapia celular. Os quatro membros dos seis animais do experimento foram submetidos a procedimento cirúrgico em que um fragmento de cada ligamento foi retirado, utilizando-se punch de biópsia. Dois dias após o procedimento, aplicações intralesionais foram realizadas, por meio de aspirado de medula óssea (bone marrow-BM), células mesenquimais derivadas de tecido adiposo (adipose tissue-AT), solução salina (positive control group-PC) ou controle (negative control-NC). Após 60 dias, biópsias foram retiradas da região de reparo dos ligamentos e foram submetidas à análise histológica (HE, tricrômio de Masson, picrosírius red) e imunoistoquímica (colágeno tipo III). Diferentes variáveis histológicas (HE e tricrômio de Masson), a intensidade de birrefringência das fibras colágenas (picrosírius red) e a expressão de colágeno tipo III foram avaliadas. Os grupos tratados apresentaram maior birrefringência (P=0,007) e alinhamento de fibras (P=0,08) comparados ao controle, para o qual o resultado não se mostrou estatisticamente significativo. Achados histológicos e imunoistoquímicos demonstraram um processo ativo de reparo tecidual em todos os grupos. Concluiu-se que os dois protocolos de terapia celular apresentaram melhora no reparo tecidual, demonstrando potencial terapêutico adjuvante no tratamento de afecções do ligamento suspensório equino.(AU)

Cartogenina associada à microperfuração do osso subcondral na reparação da cartilagem articular em equinos / Kartogenin associated to micro of the subchondral bone in the joint cartilage repair in horses

A reconstituição da cartilagem articular danificada por doenças de desenvolvimento, trauma e osteoartrite tem sido um grande desafio na veterinária. O objetivo do presente estudo foi avaliar o uso da cartogenina, uma molécula capaz de induzir diferenciação de células mesenquimais em condrócitos, associado ou não à técnica de microfratura na reparação de defeitos condrais induzidos na tróclea femoral de equinos. Foram utilizados seis equinos pesando em média (±DP) 342±1,58kg, com idade de 7,2±1,30 anos e escore corporal de 7,1±0,75, os quais foram submetidos à videoartroscopia para indução da lesão condral de 1cm2 na tróclea lateral do fêmur e à realização da técnica de microperfuração do osso subcondral de ambos os joelhos. Foram realizadas quatro aplicações semanais com 20µM de cartogenina intra-articular em um dos joelhos (grupo tratado) e solução de ringer com lactato na articulação contralateral (grupo controle). Os animais foram submetidos a avaliações física, radiográfica, ultrassonográfica, por um período de 60 dias. Não houve qualquer diferença estatística entre as articulações tratadas e as controle. A terapia com cartogenina, segundo protocolo utilizado, não produziu melhora clínica em lesões osteocondrais induzidas e tratadas com microperfurações na tróclea lateral do fêmur em equinos.(AU)

Articular cartilage reconstruction is still a challenge in Veterinary Medicine. The aim was to evaluate the therapeutic effects of kartogenin, a small molecule that promotes chondrocyte differentiation, in the repair of induced chondral defects pretreated with subchondral drilling. Six horses with a mean (± SD) weight of 342 ± 1.58Kg, aging 7.2 ± 1.30 years, and with a mean 7.1 ± 0.75 body score condition were used. In both stifles, a 1cm2 chondral defect was induced in the lateral femoral trochlea followed by treatment with subchondral drilling. Four intra-articular injections with kartogenin (20mM) were performed weekly in one stifle (treated group). The same procedure using saline solution was performed in the contralateral joint (control group). Clinical, radiographic, ultrasound evaluations were performed for a period of 60 days. No statistical differences were detected between groups in any of the studied variables. Although kartogenin has shown to improve articular cartilage repair in laboratory animal models, the same was not observed in this equine model. In conclusion, the kartogenin therapy, according to the used protocol, did not promote any clinical benefit in equine femoral trochlear defects pretreated with subcondral drilling.(AU)

Mechanical nociceptive thresholds of dorsal laminae in horses after local anaesthesia of the palmar digital nerves or dorsal branches of the digital nerve.

We examined the hypothesis that the palmar digital nerves (PDNs), but not the dorsal branches (DBs) of the digital nerves, innervate the sensitive dorsal laminae of the equine foot by evaluating the effects of perineural anaesthesia of the PDNs and DBs separately on pain sensation evoked via mechanical stimulation of the dorsal laminae and other regions of the equine foot. Six clinically normal mares were used in a crossover design. A portable dynamometer was used to evaluate mechanical nociceptive thresholds at different points on the dorsal laminae, bulbs of the heel, coronary band and sole before and after the horses underwent perineural injection of PDNs or DBs with a local anaesthetic solution (treated group) or an isotonic saline solution (control group). Cornified tissue was removed from the sole and the dorsal aspect of the hoof wall before evaluations of mechanical nociceptive thresholds. Anaesthetising PDNs distal to the DBs increased mechanical nociceptive thresholds compared to baseline values (P <0.001) at sites assessed in the dorsal laminae, sole, and the bulbs of the heels. Anaesthetising DBs increased mechanical nociceptive thresholds compared to baseline values (P <0.01) only at sites assessed at the most proximal aspect of the foot (i.e., coronary band sites). In conclusion, PDNs, not DBs, are primarily responsible for pain signal transmission evoked by pressure in the dorsal laminae of the foot of clinically normal horses.

Alterações radiográficas do aparato podotroclear de equinos da Polícia Militar de Minas Gerais sem sinais clínicos de doença do osso navicular / Radiographic changes in the podotroclear apparatus from Minas Gerais State Military horses without clinical signs of navicular disease

Os objetivos deste experimento foram identificar e associar alterações radiográficas do aparato podotoclear de equinos do Regimento de Cavalaria Alferes Tiradentes da Policia Militar do estado de Minas Gerais sem histórico e sinais clínicos de doença do osso navicular. Foi avaliado um total de 33 equinos, de ambos os sexos, com idade entre 10 e 20 anos. Os dígitos torácicos foram radiografados de forma padronizada nas projeções lateromedial (LM), dorsoproximal palmarodistal 65º (DPPD) e palmaroproximal palmarodistal (SK). A radiopacidade medular aumentada em projeção SK foi a principal alteração radiográfica detectada. Essa alteração foi associada a maior número de invaginações sinovais, a maior espessura de cortical em relação à medular em exposição SK e a maior relação corticomedular em exposição LM (P<0,05). Esses achados indicam uma predisposição da população equina para desenvolver a síndrome do osso navicular, possivelmente associada ao trauma repetitivo promovido pelo constante trabalho em piso duro.

The aims of this study were to identify and associate radiographic changes of podotoclear apparatus in horses from the Tiradentes Calvary Regiment of the Military Police of Minas Gerais State without history and clinical signs of navicular disease. 33 horses from both sexes, aged between 10 and 20 years were evaluated. The thoracic digits were radiographed in a standardized manner in lateralmedial (LM), palmaroproximal-distodorsal 65o(DPPD) and palmaroproximal-distopalmar (SK) projections. The increased medullary radiopacity in SK projection was the main radiological change detected and was associated with a higher number of synoval invaginations, increased cortical thickness in relation to medulla in SK exposure and increased corticomedullar in LM exposure (P < 0.05). These findings indicate a predisposition of this population to develop navicular syndrome, which is possibly associated with repetitive trauma promoted by constant work on hard floors.

Standardized method to obtain dermo-epidermal junction samples from bovine hoof / Método padronizado para obtenção de amostras da junção derme-epiderme do casco de bovinos

As afecções podais em bovinos causam importante impacto econômico negativo na bovinocultura. Pesquisas têm sido realizadas com o objetivo de avançar no entendimento dos processos ocorridos na junção derme-epiderme do casco de bovinos com laminite e nos demais tecidos moles durante as lesões infecciosas. Apesar disso, não foram encontrados na literatura consultada estudos que descrevessem um método padronizado para a obtenção de amostras do tecido laminar do casco. Nesse contexto, foi necessário criar e estabelecer um método viável para a colheita de amostras da junção derme-epiderme, de modo a viabilizar o estudo de pós-graduação que originou esta comunicação. O objetivo é relatar um método padronizado, testado e bem-sucedido para obtenção de amostras da junção derme-epiderme do casco de bovinos em suas regiões solear, axial e dorsal. Foram obtidos fragmentos transversais das unhas de vacas abatidas em frigorífico. A espessura desses fragmentos foi de 1,5cm, aproximadamente, e contemplava as regiões solear, axial e dorsal do casco. De forma sistematizada, amostras da junção derme-epiderme de cada uma dessas regiões foram removidas, fixadas em formol, processadas e incluídas em parafina. A análise usando microscopia de luz demonstrou cortes histológicos íntegros e sem artefatos, que permitiram ampla avaliação das estruturas tanto da derme quanto da epiderme. Concluiu-se que o método proposto viabiliza a obtenção de amostras de padrão e qualidade adequados ao estudo do tecido laminar do casco bovino.(AU)

Estudo da correlação de medidas radiográficas indicadoras de laminite em éguas da raça Mangalarga Marchador com e sem sinais de sobrepeso / Correlation study about radiographic measurements signaling laminitis in Mangalarga Marchador mares with or without signs of overweight

A avaliação radiográfica do casco é essencial no diagnóstico e na avaliação da laminite em equinos, contudo poucos estudos têm sido feitos em raças nacionais. O objetivo deste trabalho foi realizar a morfometria de imagens radiográficas obtidas do dígito de éguas Mangalarga Marchador (MM), a fim de obter um perfil de medidas indicadoras de laminite nessa população e comparar grupos sem (escore corporal 5 e 6) e com (escore corporal 7 e 8) sinais de sobrepeso. Não houve diferença significativa entre os valores para as medidas dos dois grupos (P>0,05), mas verificou-se correlação positiva entre a distância entre os planos da linha coronária e do ápice do processo extensor (afundamento da falange distal) e indicadores de deposição de gordura localizada no pescoço e na base da cauda. Os achados demonstram que a morfometria radiográfica do dígito dessa população de equinos Mangalarga Marchador difere da de raças estrangeiras. Além disso, nos animais estudados, éguas com escore corporal 7 e 8 não aparentaram estarem mais sujeitas à laminite, uma vez que não houve diferença entre a morfometria de éguas com escore inferior. Entretanto, as correlações positivas entre índices de obesidade e a distância de afundamento da falange distal indicam que éguas Mangalarga Marchador também estão sujeitas à ocorrência de laminite associada à obesidade...

The radiographic evaluation of the hoof is essential in the diagnosis and follow-up of equine laminitis; however, few studies have been conducted in Brazilian breeds. The aim was to perform the morphometry of radiographic images taken from the digit of Mangalarga Marchador in order to obtain a profile of measurements indicative of laminitis in this population. We also compared measurements form mares without (body score 5 and 6) and with (body score 7 and 8) signs of overweight. There was no significant difference between measurements from the two groups (P> 0.05), but there was significant positive correlation between founder distance and signs of adiposity in the neck and in the base of the tail. Findings from this study demonstrate that radiographic morphology of the hoof from this population of Mangalarga Marchador mares differ from standard international reference values. Furthermore, in this group of mares, those with body condition grading 7 and 8 did not seem to be more prone to develop laminitis, since there was no difference when they were compared with mares showing lower grades. However, a significant correlation among founder distance and signs of adiposity in the neck and base of tail indicate that Mangalarga Marchador mares are also prone to obesity-associated laminitis...

Estudo radiográfico do posicionamento da falange distal e suas possíveis correlações com obesidade em equinos de patrulhamento da Polícia Militar do Estado de Minas Gerais / Radiographic study of the distal phalanx position and their possible correlation with obesity in patrol horses from the Military Police of Minas Gerais

Com o objetivo de se verificarem possíveis correlações entre a falange distal, o estojo córneo e a obesidade, 55 equinos de patrulhamento provenientes do Regimento de Cavalaria Alferes Tiradentes do Estado de Minas Gerais - RCAT tiveram seus dígitos torácicos radiografados. Posteriormente, os animais foram classificados quanto ao acúmulo de tecido adiposo regional por métodos subjetivos (escore corporal e escore de pescoço) e objetivos (índice de massa corporal, circunferência do pescoço e determinação de espessura do tecido adiposo por meio de ultrassonografia na inserção da cauda e do abdômen). Na população estudada, o índice de massa corporal evidenciou que 52,6 por cento dos equinos se encontravam acima do peso. A circunferência do pescoço a 50 por cento de seu comprimento dorsal e a medida ultrassonográfica na inserção da cauda se mostraram os melhores métodos objetivos para quantificar o acúmulo de tecido adiposo. Foram identificadas particularidades radiográficas características da população estudada que diferem de parâmetros internacionais. Observaram-se correlações significantes entre sinais de obesidade e medidas radiográficas indicadoras de laminite, sugerindo associação entre essas duas condições na população estudada...

With the aim to verify possible correlations between the spatial relationship between the distal phalanx and the hoof and signs of obesity, 55 horses from the Cavalry Regiment Alferes Tiradentes of Minas Gerais State Police - RCAT had x-rays taken from their thoracic hoofs. After that, horses were classified based on their subjective (body condition and neck scores) and objective (body mass index, neck circumferences, ultrasound measurement of fat tissue of the tail and on abdomen) methods for adiposity. Within the population, the body mass index showed that 52.6 percent of horses were overweight. Neck circumference at 50 percent of its dorsal length and ultrasound measurement of fat thickness on the insertion of the tail were the best objective methods. We identified specific radiographic characteristics of the population that were different from international parameters. Significant correlations among signs of obesity and measurements that indicate lamintis were found, suggesting association between these conditions in this horse population...

Relação entre obesidade, insulina plasmática e posicionamento da falange distal em equinos da raça Crioula / Relationship between obesity, insulin and placement of plasma in equine distal phalanx of breed creole

Verificaram-se características radiográficas do posicionamento da falange distal em relação ao estojo córneo em equinos da raça Crioula e correlacionaram-se tais achados com sinais de obesidade e concentrações plasmáticas de insulina. Consideraram-se dois grupos com base no escore da condição corporal (ECC). A média de idade entre os grupos foi de 9,2±5,8 anos em indivíduos normais (ECC 5-7) e de 10,3±3,7 anos em obesos (ECC 8-9). Diferenças estatísticas entre grupos ocorreram para valores de peso, perímetro torácico, escore da condição corporal, escore da crista do pescoço, comprimento do pescoço, circunferência do pescoço em três regiões referentes a 25%, 50% e 75% do comprimento do pescoço e entre o posicionamento da falange distal em relação ao estojo córneo. O ângulo formado entre as superfícies dorsais de falange distal e casco (ângulo de rotação) correlacionou-se estatisticamente com ECC (r = 0,30; P=0,02) e com peso e perímetro torácico (r = 0,50; P<0,01). Quanto à concentração de insulina plasmática, foram encontradas correlações positivas com ECP (r = 0,40; P<0,01) e com ângulo de rotação (r = 0,23; P = 0,08), e correlação negativa com idade (r = -0,42; P<0,01). Em oito animais (27%) o ângulo de rotação foi maior que 2 graus; destes, 25% eram normais e 75%, obesos (P<0,05). Aparentemente, em equinos da raça Crioula, características morfométricas no casco diferiram dos padrões internacionais obtidos de outras raças. A obesidade interferiu na relação espacial da falange distal com o estojo córneo, indicando que os animais obesos dessa raça são mais propensos a desenvolver laminite.

The radiographic relationship of the distal phalanx with the hoof capsule was verified in Creole breed horses and these findings correlated with signs of obesity and insulin blood levels. Horses were divided in two groups based on their body score condition (ECC). The average age was 9.2±5.8 years in normal (ECC 5-7) and 10.3±3.7 years in the obese group (ECC 8-9). Statistical differences between groups (P<0.05) were detected for values of weight, thoracic girth, body score condition, neck score (ECP), neck length, neck circumference into three regions based on 25% (P25), 50% (P50) and 75% (P75) of the length of the neck and phalanx and hoof capsule relationship. The angle between the dorsal aspects of distal phalanx and hoof wall (rotation angle) statistically correlated with ECC (r = 0.30; P=0.02) and with weight and thoracic girth (r = 0.50; P<0.01). Plasma insulin concentrations positively correlated with ECP (r = 0.40, P <0.01) and rotation angle (r = 0.23, P = 0.08) and negatively with age (r = -0.42, P <.01). In eight animals (27%) rotation angle was greater than 2 degrees, of which 25% were normal and obese 75% (P <0.05). Apparently in Creole horses, morphometric characteristics of the hoof differ from international standards obtained from other breeds. Obesity interfered with the spatial relationship of the distal phalanx with the hoof capsule, indicating that obese animals of this breed are more likely to develop laminitis.

Efeito de anti-inflamatórios não esteroidais na apoptose de células epidermais lamelares de equinos com laminite / Effect of nonsteroidal anti-inflammatory drugs on apoptosis of epidermal lamellar cells of equines with laminitis

O objetivo deste trabalho foi avaliar a influência da administração dos anti-inflamatórios não esteroidais (AINEs) cetoprofeno, fenilbutazona e flunixin meglumine sobre o índice apoptótico de células epiteliais do tecido lamelar de cavalos com laminite induzida por administração de amido. Foram empregados 20 equinos hígidos, divididos em quatro grupos experimentais (n=5): solução salina, cetoprofeno, fenilbutazona e flunixin meglumine. O tecido lamelar foi coletado por biópsia, fixado e corado pela técnica de TUNEL. À marcação positiva por essa técnica adicionou-se a avaliação morfológica celular para identificação da apoptose. Não houve diferença significativa no índice apoptótico entre os grupos tratados com anti-inflamatórios e o controle (P>0,05). Os anti-inflamatórios não interferiram sobre o índice apoptótico possivelmente porque foram administrados após a fase prodrômica da laminite e/ou porque não são eficazes em alterar a dinâmica da apoptose. Concluiu-se que a administração de anti-inflamatórios não esteroidais após a fase prodrômica da laminite não contribui para uma intervenção no curso da apoptose no tecido lamelar de cavalos com laminite quando comparados ao grupo controle não tratado. Outros estudos, com diferentes períodos de avaliação, são necessários para esclarecer os efeitos dos anti-inflamatórios não esteroidais na fisiopatologia da laminite em equinos, especialmente no que concerne à participação da apoptose.

The aim of this study was to evaluate the influence of the administration of anti-inflammatory drugs (NSAIDs) ketoprofen, phenylbutazone and flunixin meglumine on the apoptotic index of the epithelial cells of lamellar tissue of horses with induced laminitis. 20 healthy horses were employed and underwent induction of laminitis by administration of starch, divided into four groups with induced laminitis (n = 5): saline, ketoprofen, phenylbutazone and flunixin meglumine. The lamellar tissue was collected by biopsy, fixed and stained with the TUNEL technique. All that were stained positive by this technique were added to the cell morphological identification of apoptosis. No significant difference was found in the apoptotic index between the groups treated with anti-inflammatory and controls (P> 0.05). It was concluded that the administration of NSAIDs after the prodromal phase of laminitis does not contribute to an intervention in the course of apoptosis in the lamellar tissue of horses with laminitis when compared to the untreated control group. Other studies with different evaluation periods are needed to clarify the effects of anti-inflammatory non-steroidal drugs in the pathophysiology of laminitis in horses, especially regarding the role of apoptosis.

Hindlimb laminar inflammatory response is similar to that present in forelimbs after carbohydrate overload in horses.

REASONS FOR PERFORMING STUDY: A significant proinflammatory response is known to occur in the forelimb lamina after carbohydrate administration. As the hindlimbs are often less affected by laminitis compared with the forelimbs, we assessed hindlimb inflammatory response in the early stages of carbohydrate-induced laminitis to determine whether differences in the response existed. OBJECTIVE: To determine whether a similar proinflammatory response occurs in the hindlimb laminae to that previously reported for the forelimb. METHODS: Archived laminar samples from 12 horses administered 17.6 g of starch (85% corn starch, 15% wood flour)/kg bwt via nasogastric tube that were anaesthetised either after developing a temperature >38.9°C (DEV; n = 6) or at the onset of Obel grade 1 lameness (OG1; n = 6) were used in addition to 6 control horses (CON) that were anaesthetised 24 h after administration of water. Real-time quantitative polymerase chain reaction for selected proinflammatory mediators and MAC387 immunohistochemistry were performed. The data were analysed nonparametrically to compare groups. RESULTS: Increases in laminar MAC387-positive leucocytes and laminar messenger ribonucleic acid (mRNA) concentrations (P<0.05) for interleukin-1ß, interleukin-6, cyclo-oxygenase-2, chemokine (C-X-C motif)ligand (CXCL)1 and CXCL8 were present in both fore- and hindlimb laminae from horses with OG1 lameness. Both CXCL1 and CXCL8 were also increased in forelimb and hindlimb laminae in the DEV horses. CONCLUSIONS: Administration of carbohydrate resulted in a similar inflammatory response in the hindlimb laminae to that previously reported for the forelimb laminae. These findings suggest that other factors, such as weightbearing, may play an important role in the development of laminitis after a systemic inflammatory condition develops. POTENTIAL RELEVANCE: Evidence of inflammation in the hindlimb laminae suggests that the hindfeet should be addressed in the septic horse at risk for laminitis; however, laminitis is often less severe in the hindlimbs due to other factors, such as weightbearing and hoof angle.

Análise biomecânica ex vivo de um modelo de haste intramedular de polipropileno para osteossíntese em úmeros de bezerros / Ex vivo biomechanics assay of a model of polypropylene intramedullary nail for calf humeral osteosynthesis

Foram utilizados 12 pares de úmeros obtidos de bezerros machos da raça Holandesa, com idades entre 15 e 30 dias. Os úmeros esquerdos foram mantidos íntegros, e os direitos foram fraturados de forma oblíqua em sua diáfise, na transição entre os terços médio e proximal. A redução da fratura foi feita pela aplicação intramedular de haste de polipropileno, bloqueada por dois parafusos corticais de aço inoxidável, dispostos transversalmente em cada fragmento ósseo. Seis pares de ossos foram submetidos ao teste de compressão, e seis ao teste de flexão, utilizando-se uma máquina universal de ensaios. Nos testes de compressão, as cargas médias de ruptura foram 738,3N e 473,3N, e nos testes de flexão 322,4N e 117,9N, para os ossos íntegros e fraturados, respectivamente. Comparando-se o grupo de ossos fraturados com o grupo de ossos íntegros, verificou-se que o sistema proposto foi capaz de resistir a 66,4 por cento das cargas médias quando submetido à compressão, e a 36,6 por cento quando submetido à flexão. Úmeros fraturados e tratados com haste intramedular de polipropileno apresentaram resistência limitada se comparados aos ossos íntegros.

A total of 12 pairs of humeri from male calves 15 to 30 days old were used. The left humeri remained unchanged and the right ones were fractured in the diaphysis between proximal and middle thirds. The fracture was fixed with a polypropylene intramedullary nail interlocked with two steel bone screws crossed along each segment. Six pairs of bones were subjected to a compression test and the others to a flexural test using a universal testing machine. In the compression tests, the mean rupture loads were 738,3N and 473,3N, and in the flexural tests they were 322,4N and 117,9N for the intact and fractured bones respectively. Fractured bones fixed with the proposed model were able to resist 66.4 percent of the load during compression and 36.6 percent during bending when in comparison to intact bones. Fractured humeri treated with polypropylene intramedullary nail showed limited resistance compared to intact ones.

Ocorrência de doença infundibular, sobremordida e ganchos em equinos de cavalaria militar / Infundibular disease, over-bite, and dental hooks occurrence in military horse

Avaliou-se a ocorrência da doença infundibular (DI) e a associação entre sobremordida (SM) e ganchos dentários rostral e caudal da maxila e mandíbula. Utilizaram-se 88 equinos - 52 machos e 36 fêmeas -, entre três e 27 anos. Para os exames odontológicos, os animais foram contidos em brete e sedados com xilazina 10 por cento a 0,5mg/kg IV e utilizaram-se abridor de boca, fotóforo elétrico e sonda odontológica de aço inox. Agruparam-se os equinos por idade. O grupo 1 foi formado por animais até nove anos; o G2 de 10 a 14 e G3 de 15 a 27 anos. Foi diagnosticada DI em (37,5 por cento) animais, nos dentes molares e pré-molares. A incidência maior de DI foi nos dentes 109 (11,4 por cento) e 209 (12,5 por cento). Houve correlação positiva entre a idade e o número de dentes acometidos (r=0,26; P<0,02). A maior ocorrência de DI no grupo mais acometido (G3) foi nos dentes 108 e 208. Verificaram-se 66 por cento de SM e 65 por cento de ganchos. Observou-se correlação entre SM e presença total de ganchos (r=0,26, P=0,016), entre SM e ganchos rostrais maxilares e mandibulares (r=0,25,P=0,016) e ganchos rostrais maxilares(r=0,24, P=0,02). Animais com ganchos pré-molares maxilares tiveram 2,8 vezes mais chance de apresentarem SM (IC 95 por cento = 1,1 a 7,1).

The occurrence of infundibular disease (ID) and the association between over-bite (OB) and rostral and caudal hooks on teeth of the maxilla and jaw were evaluated in 88 horses - 52 males and 36 females - aging from between 3 and 27 years old. The horses were restrained in stocks, sedated with xylazine and examined using a mouth-speculum and a stainless steel pick. The data were recorded on individual charts. The animals were grouped by age: group 1: 3 to 9, group 2: 10 to 14, and group 3: 15 to 27 years old. ID was identified on the premolar and molar teeth in 37.5 percent of horses. There was a positive correlation between age and number of affected teeth (r=0.26, P<0.02). The most affected teeth were the 109 (11.4 percent) and 209 (12.5 percent). The highest occurrence of ID in the most affected group (G3) was on the 108 and 208 teeth. There were 66 percent of OB and 65 percent of hooks. There was a correlation between OB and the presence of total (r=0.26, P=0.016), maxillary and mandibular (r=0.25, P=0.016), and maxillary rostral hooks (r=0.24, P=0.02). Only the association between OB and maxillary rostral hooks was significant. Animals with maxillary pre-molars hooks were 2.8 times predisposed to have OB (CI 95 percent=1.1 to 7.1).

Laminar leukocyte accumulation in horses with carbohydrate overload-induced laminitis.

BACKGROUND: While there is evidence of laminar leukocyte infiltration in black walnut extract (BWE)-induced laminitis, there is no such evidence for carbohydrate overload (CHO) laminitis. OBJECTIVE: To assess presence of leukocytes and signs of epidermal stress/injury in the laminar tissue from horses with CHO-induced laminitis. ANIMALS: Twenty-four adult horses. METHODS: Immunohistochemistry for myeloid cell markers calprotectin (CP) and monocyte-specific marker (CD163) was performed on laminar sections obtained from 2 groups of horses in the CHO model: the developmental time point (DTP) group (n = 6) and the onset of lameness (LAM) group (n = 6), and a control (CON) group (n = 8). RESULTS: DTP was characterized by an increase in CP(+) leukocytes (7.8-fold increase versus CON, P < .001), and LAM time point was characterized by a more marked increase in laminar CP(+) (108.5-fold, P < .001) and mild increase in CD163(+) (1.9-fold, P = .007) cell counts. Increased CP epidermal signal (indicating epidermal stress or injury) occurred consistently at the LAM time point, although histological evidence of basement membrane (BM) detachment was minor, only being present in 3/6 horses. CONCLUSIONS AND CLINICAL RELEVANCE: Maximal laminar leukocyte infiltration and epithelial stress occurred at the onset of lameness in the CHO model showing a different temporal pattern from the BWE model, where maximal leukocyte infiltration clearly precedes epithelial stress. Leukocyte infiltration before major histological changes in the CHO model indicates that leukocyte infiltration can be a cause of and not a reaction to BM degradation and structural failure.

Presence of mononuclear cells in normal and affected laminae from the black walnut extract model of laminitis.

REASONS FOR PERFORMING STUDY: There is increasing evidence of involvement of inflammatory cells in acute laminitis. OBJECTIVE: To immunolocalise monocytes/macrophages and B and T lymphocytes in the laminar tissue of normal horses and those with black walnut extract (BWE)-induced laminitis. METHODS: Immunohistochemistry was used in archived laminar tissue samples from 20 horses divided equally into 4 groups: control animals (CON), and those administered BWE at 1.5 h (1.5H DTP group), at the onset of leucopenia (3H DTP group) and at the onset of lameness (LAM group). Antibodies against CD3, CD20 and CD163 were used to recognise lymphocytes (T and B) and monocytes/macrophages, respectively. RESULTS: Mononuclear cells were present in laminar tissue of normal horses. The majority of CD3- and CD20-positive lymphocytes were localised around the deep dermal vessels but were also evident around vessels of the primary dermal laminae. CD163-positive macrophages were primarily perivascular in deep dermis or in dermal laminae. No changes in the number of laminar B or T lymphocytes occurred at any time point post BWE administration. However, increases (P=0.0016) in laminar CD163-positive cells occurred in the secondary dermal laminae (SDL) in the 1.5H DTP and 3H DTP groups, returning to basal values in LAM group. CONCLUSIONS: Lymphocyte and macrophage populations are present in the laminar tissue of clinically normal horses and BWE administration induces an increase in CD163-positive macrophages in SDL. POTENTIAL RELEVANCE: Both the host tissue population of mononuclear cells and the influx of monocytes may play an important role in the pathophysiological changes leading to laminar injury.

Laminar inflammatory gene expression in the carbohydrate overload model of equine laminitis.

REASONS FOR PERFORMING STUDY: There is a need to assess the laminar inflammatory response in a laminitis model that more closely resembles clinical cases of sepsis-related laminitis than the black walnut extract (BWE) model. OBJECTIVES: To determine if a similar pattern of laminar inflammation, characterised by proinflammatory cytokine expression, occurs in the CHO model of laminitis as has been previously reported for the BWE model. METHODS: Sixteen horses administered 17.6 g of starch (85% corn starch/15% wood flour)/kg bwt via nasogastric (NG) tube were anaesthetised either after developing a temperature>38.9°C (DEV group, n=8) or at onset of Obel grade 1 lameness (OG1 group, n=8). Control horses (CON group, n=8) were anaesthetised 24 h after NG administration of 6 l of deionised water. Laminar tissue was collected from horses while under anaesthesia, followed by humane euthanasia. Real time-quantitative PCR was used to assess laminar mRNA concentrations of genes involved in inflammatory signalling. RESULTS: Increased mRNA concentrations (P<0.05) for IL-1ß, IL-6, IL-12p35, COX-2, E-selectin and ICAM-1 were present in laminae from horses with OG1 lameness but not at the DEV time, when compared to the CON horses. No differences between the groups were found for IL-2, IL-4, IL-10, TNF-α, IFN-γ or COX-1 at either the DEV or OG1 time points. CONCLUSIONS: There was a notable difference in the temporal pattern of inflammatory events between the BWE and CHO models, with the majority of laminar inflammatory events appearing to occur at or near the onset of lameness in the CHO model, whereas many of these events peak earlier in the developmental stages in the BWE model. This suggests that, in addition to circulating inflammatory molecules, there may be a local phenomenon in the CHO model resulting in the simultaneous onset of multiple laminar events including endothelial activation, leucocyte emigration and proinflammatory cytokine expression. POTENTIAL RELEVANCE: The similar (although somewhat delayed) inflammatory response in the CHO model of laminitis indicates that inflammatory signalling is a consistent entity in the pathophysiology of laminitis.

Morphological abnormalities and apoptosis in lamellar tissue of equines after intestinal obstruction and treatment with hydrocortisone / Alterações morfológicas e apoptose em tecido laminar de equinos após obstrução intestinal e tratamento com hidrocortisona

Four experimental groups of equines were used in order to study morphological abnormalities and apoptosis in lamellar tissue. Group Cg (control) was composed of animals without any surgical procedure; group Ig (instrumented), animals that underwent enterotomy; group Tg (treated), animals that were subjected to intestinal obstruction and were treated with hydrocortisone; and group Ug (untreated), animals that were subjected to intestinal obstruction without treatment. The lamellar tissue was analyzed regarding the presence of tissue abnormalities and apoptosis. No morphological abnormalities were observed in animals of surgical groups, and no difference in apoptosis was observed between groups. It was concluded that intestinal obstruction allowed laminitis to develop, probably by systemic activation, and that the maneuvers performed in the enterotomy aggravated the process. Hydrocortisone did not aggravate the lesions of the lamellar tissue.

Foram utilizados quatro grupos de equinos para estudar alterações morfológicas e apoptose no tecido lamelar. O grupo CG (controle) foi composto por animais sem o procedimento cirúrgico; o grupo Ig (instrumentado), por animais submetidos à enterotomia; o grupo Tg (tratado), por animais submetidos à obstrução intestinal e tratados com hidrocortisona; e o grupo Ug (não tratado), por animais submetidos à obstrução intestinal, sem tratamento. O tecido laminar foi analisado quanto à presença de alterações morfológicas e de apoptose. Foram observadas alterações morfológicas nos equinos submetidos a procedimento cirúrgico, mas não houve diferença entre os grupos com relação às células apoptóticas. Conclui-se que a obstrução intestinal permite o desenvolvimento da laminite provavelmente por ativação sistêmica e que as manobras realizadas na enterotomia podem ser consideradas como agravantes no processo. A hidrocortisona não agravou as lesões do tecido laminar.

Alterações ultraestruturais nas vilosidades do jejuno de equinos após distensão / Ultraestructural alterations in the equine jejune villi after distension

O objetivo do presente estudo foi analisar as alterações ultraestruturais nas vilosidades do jejuno de seis equinos submetidos à distensão intraluminal com solução salina. A pressão intraluminal foi mantida em 25cm de água durante duas horas. As amostras de mucosa intestinal colhidas às: zero hora; duas horas de distensão; e duas horas e 12h de descompressão foram analisadas por meio de microscopia eletrônica de varredura. Avaliaram-se a área e o perímetro das vilosidades e sua densidade, usando-se um programa computacional de análise de imagens (Image J). A distensão luminal promoveu aumentos da área e do perímetro das vilosidades intestinais. Essa alteração ultraestrutural ocorreu somente 12h após a descompressão e considerou-se que a provável causa seria o edema promovido por aumento da permeabilidade vascular decorrente de um processo de isquemia e reperfusão da mucosa intestinal. Concluiu-se que a distensão intraluminal do jejuno equino promoveu, tardiamente, aumento das dimensões das vilosidades intestinais.

The ultra-structural alterations in the equine jejune villi caused by intraluminal distension were analyzed. Six animals had a jejunum segment distended with saline solution. The intraluminal pressure was maintained in 25cm of water for 2h. The mucosal samples collected (0h, 2h of distension, 2h and 12h of decompression) were analyzed with scan electronic microscopy (SEM). The area and the perimeter of the villi, as well as their density, were analyzed using a specific software for image analysis (Image J). The luminal distention and decompression induced an increase on villi dimensions (area and perimeter). This ultrastructural alteration occurred just 12h after decompression, possibily due to edema caused by the increase of vascular permeability resulting from ischemia and reperfusion of the intestine mucosa. The intraluminal distension of the equine jejune caused a delayed increase of the intestine villi dimensions.

Effect of intravenous lidocaine administration on laminar inflammation in the black walnut extract model of laminitis.

REASONS FOR PERFORMING STUDY: Laminitis is a serious complication of horses suffering from sepsis/endotoxaemia-related events. Laminitis in horses and organ injury in human sepsis are both reported to involve inflammatory injury to the laminae/organs including early activation of endothelium and leucocytes leading to emigration of neutrophils into the tissue interstitium. In the black walnut extract (BWE) model, systemic inflammatory events coincide with marked increase in laminar mRNA concentrations of inflammatory genes including proinflammatory cytokines (i.e. IL-1beta, IL-6), COX-2, chemokines (i.e. IL-8) and endothelial adhesion molecules (i.e. ICAM-1 and E-selectin). In models of human sepsis, i.v. lidocaine has been reported to decrease leucocyte and endothelial activation, and the expression of proinflammatory cytokines and chemokines. OBJECTIVES: To evaluate the effect of i.v. lidocaine therapy on the inflammatory processes documented to occur in the BWE model of laminitis. METHODS: Twelve horses were administered BWE and treated immediately with either lidocaine (1.3 mg/kg bwt bolus, followed by 0.05 mg/kg bwt/min CRI, n=6) or saline (n=6) for 10 h. At 10 h post BWE administration, laminar samples were obtained under general anaesthesia for assessment of proinflammatory gene expression (using RT-qPCR) and leucocyte emigration (via CD13 immunohistochemistry). At 0, 3 and 10 h post BWE administration, skin samples were obtained for assessment of leucocyte emigration (via calprotectin immunohistochemistry). RESULTS: No significant differences between groups were noted for inflammatory gene mRNA concentrations (IL-1beta, IL-6, IL-8, COX-2) or for number of leucocytes present within the laminar interstitium or skin dermis. Increased (P<0.05) laminar E-selectin mRNA concentrations were present in the LD group (vs. SAL group). CONCLUSIONS: Continuous administration of i.v. lidocaine does not inhibit inflammatory events in either the laminae or skin in the horse administered black walnut extract. POTENTIAL RELEVANCE: This work questions the use of continuous i.v. administration of lidocaine as an effective anti-inflammatory therapy for systemic inflammation.