Relação entre obesidade induzida e laminite endocrinopática em equinos Mangalarga Marchador: aspectos clínicos, laboratoriais, morfométricos e patológicos

• Ano de defesa: 2017
• Autor(a) principal: Rodrigo Martins Ribeiro
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Biomarcador; Laminite endocrinopática; Síndrome Metabólica Equina; Biópsia; Resistência à insulina; Disturbios do metabolismo; Cavalo marchador Doenças Diagnostico; Obesidade; Laminite
• Link de acesso: http://hdl.handle.net/1843/SMOC-AKJQ9N

Equine Metabolic Syndrome (EMS) is characterized by being a metabolic disorder associated with obesity that predisposes horses to laminitis, with the central point being insulin resistance. The great majority of horses and ponies affected by MS present generalized or regional obesity. However, not all horses with EMS are obese and not all obese animals develop insulin deregulation (ID). Other phenotypic components that may be associated with EMS, such as the upregulation of inflammatory indicators, propensity to develop arterial hypertension, infertility, hypertriglyceridemia and hyperleptinemia have been proposed. Laminitis originating from EMS has as main characteristic to have a subclínic profile, with important alterations in the structures of the hull, before even presenting symptoms. The objective of this thesis was to study the metabolic alterations caused by obesity in equines, correlating them with tissue and morphometric alterations of the hooves through the induction of weight gain in order to obtain tools for an early diagnosis for EMS. A total of 9 adult horses, 4 castrated males and 5 females, with mean initial body score (± SD) of 2.9 ± 1, were submitted to a hypercaloric diet for the induction of weight gain during one Experimental period of 150 days, reaching ECC of 8.3 ± 1. Blood samples of venous origin were used to evaluate the plasma variables at 15-day intervals for the measurement of HDL-c, LDL-c, VLDL-c, NEFA, fructosamine, glucose, cholesterol and triglycerides. Body weight was measured at 15-day intervals for body weight, adipose tissue accumulation in the horsehair region, fat accumulation at the base of the tail with the use of ultrasonography and the use of Measure tape was measured at the circumference of the neck at three predefined points with 25, 50 and 75% relative to the length measurement. For the histopathological analysis data were collected before and after 150 days of obesity induction, the samples for the histopathological analysis were obtained with a biopsy of the dorsal wall of the hull. For the radiographic analysis, the data were collected prior to the supply of obesity induction and every 30 days during the experimental period, the digits were radiographed in the lateromedial projection, after the scanning of the images, the Metron Hoof computer program was used. The results of the present study indicated that 50% MCP and UBC demonstrated regional fat accumulation first, but ECP and 25% and 75% MCP also showed fat accumulation together, but late. Among the biomarkers, LDL-c, HDL-c, cholesterol and insulin presented significant values. Proxies and TBDGO showed resistance to compensated insulin. The radiographic and histopathological exams revealed that the third phalange modified its spatial arrangement in the corneal case and presented morphological modifications in the laminar tissue. We conclude that during the period of weight gain the animals develop metabolic and morphological modifications of the hull, proving that it is necessary to follow a clinical criterion in obese animals even without the presence of symptoms.