Made available in DSpace on 2016-04-28T20:15:26Z (GMT). No. of bitstreams: 1 2007-Tiago Marques dos Santos.pdf: 2575604 bytes, checksum: e88af70c2740e40f39ed1fb8bd423ec5 (MD5) Previous issue date: 2007-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aimed to evaluate gastrointestinal and systemic disturbances, and mucosa and gut contents of gastrointestinal tract of horses subjected to overload carbohydrate. Eight crossbreed mature horses were used with body weight (BW) average of 364kg, geldings, adapted to diet composed by grass hay and concentrate, in a 60:40 proportion. A complete randomized design was used with horses allocated in three treatments. Treatment I: (Control) (n=2) horses were slaughtered without overload carbohydrate; Treatment II (n=3) and III (n=3), horses subjected to overload carbohydrate, with gastric infusion of 17.6 g starch/kg BW, and slaughtered after 24 and 36 hours, respectively. Horses were subjected to clinical, hematological and fecal evaluations before the overload and 2, 4, 8, 12, 16, 20, 24, 28, 32 and 36 hours after overload. Four hours after overload horses became depressed and keeping until the end of evaluation, and one horse presented lameness 36 hours after overload. Any difference (P>0.05) were observed in heart rate, respiratory rate, body temperature and hoof temperature. Increase in packed cell volume and plasma protein concentration were observed 24 hours after overload, varying from 26.7 to 32.0% and 7.1 to 8.1 g/dL, respectively (P<0.05). Differences were observed (P<0.05) in plasmatic lactate concentration in zero, 20 and 28 hours after overload, with values of 0.7, 1.04 and 1.22 mmol/L, respectively. Plasma endotoxin concentration didn't cross 0.1000 EU/mL and may be not present. There were any difference (P>0.05) in fecal and digesta water content, however, fecal pH reduced along 36 hours post-overload (P <0.01), varying from 6.09 to 4.46. Content of large intestine in horses subjected to overload presented whitish-green color, milk aspect, with gas bubbles and acid odor. There weren t difference (P>0.05) in water content of feces and digesta, however, fecal pH reduced along 36 hours post-overload (P <0.01), varying from 6.09 to 4.46. Buffering capacity of ceco-colon digesta and feces were reduced in horses subjected to overload. Right dorsal colon, transverse colon and descendent colon were segments, except stomach, that presented lower pH values, varying from 4.49 to 4.56. Eosinophils infiltration were presented in mucosa and submucosa of all horses, however, only horses submitted to overload presented neutrophils and eosinophils leucocitoestase with neutrophils predominance restricted to large intestine. Tract gastrointestinal circulatory alterations observed were congestion, edema and lymphatic vessels dilatation, more evident in submucosa, with larger inflammatory cells infiltration in horses subjected to overload. Intestinal mucosa 36 hours after overload presented larger degree of imunorreactivity anti-myeloperoxidase, followed by horses evaluated at 24 hours after overload and control horses, varying from 2.7 to 4.0, 1.0 to 3.7 and 1.0 to 2.5, respectively. Overload carbohydrate in horses promoted intensive fermentation in ceco-colon, predisposing clinical disturbances, digesta alterations and mucosa and submucosa lesions at gastrointestinal tract of horses with light to moderate degree,36 hours after overload. / Este trabalho teve como objetivo avaliar as altera??es sist?micas, da mucosa e conte?do do trato gastrointestinal de eq?inos submetidos ? sobrecarga diet?tica com amido. Foram utilizados oito eq?inos adultos castrados, com peso vivo m?dio de 364 kg, adaptados a dieta composta por feno de Coastcross e concentrado, na propor??o de 60:40. Foi utilizado um delineamento experimental com tr?s tratamentos: Tratamento I (Controle) (n=2), eutan?sia dos animais sem sobrecarga com amido; Tratamentos II (n=3) e III (n=3), animais submetidos ? sobrecarga com amido, com infus?o g?strica de 17,6 g amido/kg de peso corporal e eutan?sia ap?s 24 e 36 horas, respectivamente. Os eq?inos foram submetidos a avalia??es cl?nicas, hematol?gicas e f?sico-qu?micas das fezes antes da sobrecarga e 2, 4, 8, 12, 16, 20, 24, 28, 32 e 36 horas p?s-sobrecarga. Os animais apresentaram-se ap?ticos quatro horas ap?s a sobrecarga permanecendo assim at? o final da avalia??o e apenas um animal apresentou claudica??o, 36 horas p?s-sobrecarga. N?o houve diferen?a (P>0,05) na freq??ncia card?aca, freq??ncia respirat?ria, temperatura corporal e temperatura dos cascos. Houve aumento (P<0,05) no volume globular e prote?na plasm?tica total, 24 horas p?s-sobrecarga, variando de 26,7 a 32,0% e de 7,1 e 8,1 g/dL, respectivamente. Houve diferen?a (P<0,05) na concentra??o plasm?tica de lactato no tempo zero, 20 e 28 horas p?s-sobrecarga, com valores de 0,7, 1,04 e 1,22 mmol/L, respectivamente. A concentra??o plasm?tica de endotoxinas n?o ultrapassou 0,1000 EU/mL, podendo estar at? mesmo ausente. O conte?do do intestino grosso nos eq?inos submetidos ? sobrecarga apresentou cor verde esbranqui?ada, aspecto leitoso, com bolhas de g?s e odor ?cido. N?o houve diferen?a (P>0,05) no teor de ?gua das fezes e do conte?do da digesta, no entanto, o pH fecal reduziu ao longo de 36 horas p?s-sobrecarga (P<0,01), variando de 6,09 a 4,46. Houve redu??o na capacidade de tamponamento das fezes nos eq?inos submetidos ? sobrecarga e, de forma similar, ocorreu no conte?do do ceco-c?lon. O c?lon dorsal direito, c?lon transverso e c?lon descendente foram os segmentos, com exce??o do est?mago, que apresentaram a digesta com menores valores de pH, variando de 4,49 a 4,56. ? histopatologia, a infiltra??o de eosin?filos esteve presente na mucosa e submucosa de todos os eq?inos, no entanto, somente em dois eq?inos submetidos ? sobrecarga, observou-se leucocitoestase de neutr?filos e eosin?filos, com predomin?ncia de neutr?filos no intestino grosso. As altera??es circulat?rias observadas no trato gastrointestinal foram congest?o, edema e dilata??o de vasos linf?ticos, sendo mais evidentes na submucosa, local de maior infiltra??o de c?lulas inflamat?rias nos eq?inos submetidos ? sobrecarga. A mucosa dos segmentos do trato gastrointestinal dos eq?inos eutanasiados 36 horas p?ssobrecarga apresentou maior grau de imunorreatividade anti-mieloperoxidase, seguido dos eq?inos avaliados 24 horas p?s-sobrecarga e dos eq?inos do tratamento controle, variando de 2,7 a 4,0, 1,0 a 3,7 e 1,0 a 2,5, respectivamente. A sobrecarga diet?tica com amido em eq?inos promove fermenta??o intensa no ceco-c?lon, predispondo ao aparecimento de dist?rbios cl?nicos, altera??es do conte?do da digesta e les?es de leve a moderada na mucosa e submucosa do trato gastrointestinal dos eq?inos, ap?s 36 horas da sobrecarga.