Heat Tolerance in Curraleiro Pe-Duro, Pantaneiro and Nelore Cattle Using Thermographic Images.

The objective of this study was to compare physiological and thermographic responses to heat stress in three breeds of cattle. Fifteen animals of each of the Nelore, Pantaneiro and Curraleiro Pe-Duro breeds, of approximately two years of age, were evaluated. Heart and respiratory rates, rectal and surface temperature of animals as well as soil temperature were recorded at 8:30 and 15:30 on six days. Variance, correlation, principal factors and canonical analyses were carried out. There were significant differences in the rectal temperature, heart and respiratory rate between breeds (p < 0.001). Nelore and Pantaneiro breeds had the highest rectal temperatures and the lowest respiratory rate (p < 0.001). Breed was also significant for surface temperatures (p < 0.05) showing that this factor significantly affected the response of the animal to heat tolerance in different ways. The Curraleiro Pe-Duro breed had the lowest surface temperatures independent of the period evaluated, with fewer animals that suffered with the climatic conditions, so this may be considered the best adapted when heat challenged under the experimental conditions. Thermography data showed a good correlation with the physiological indexes, and body area, neck and rump were the main points.

Infrared Thermography to Evaluate Heat Tolerance in Different Genetic Groups of Lambs.

Heat stress is considered a limiting factor for sheep production. We used information from physiological characteristics linked to heat tolerance to determine whether infrared thermography temperatures were able to separate groups of animals and determine the most important variables in this differentiation. Forty-eight four-month-old male lambs from eight genetic groups were used. Physiological (rectal temperature-RT, heart rate-HR, respiratory rate-RR) and blood traits, infrared thermography temperatures, heat tolerance indices, body measurements, weight and carcass traits were measured. Statistical analyses included variance, correlations, factor, discrimination and regression. Observing the correlations between physiological characteristics (RT, RR and HR) with temperatures measured by infrared thermography, regions for further studies should include the mean temperature of flank, nose and rump. Results show that there are strong relationships between thermograph measurements and RR, RT and HR in lambs, which are suggested to be directly correlated with heat tolerance capacity of the different genetic groups evaluated in this study. The assessment of body surface temperature measured by the thermograph could be used as a noninvasive tool to assess heat tolerance of the animals.

The effect of ensiling and haymaking on the concentrations of steroidal saponin in two Brachiaria grass species / O efeito da ensilagem e fenação sobre as concentrações de saponina esteroide em duas espécies de gramínea Brachiaria

Brachiaria (signalgrass) is now the most widely used tropical grass genus in Central and South America. However, Brachiaria spp. can cause hepatogenous photosensitization in livestock. Steroidal saponins, specifically protodioscin, present in Brachiaria spp. may be responsible for liver injury and subsequent photosensitization. The objective of this study was to determine the effect of ensiling Brachiaria decumbens and Brachiaria brizantha or making hay from Brachiaria decumbens on the concentrations of steroidal saponin in these grasses. Brachiaria grass had no detectable levels of the saponin protodioscin after 24 days of ensiling. In addition, in Brachiaria decumbens, the concentration of the protodioscin decreased 48% over the first three days after haymaking and then remained constant. These results suggest that livestock consuming Brachiaria either as silage or hay may have reduced risk of intoxication by protodioscin. .

Brachiaria atualmente é o gênero de gramínea tropical mais amplamente utilizado na América Central e do Sul. Entretanto, as espécies de Brachiaria podem causar fotossensibilização hepatógena em animais de produção. Saponinas esteroides, especificamente protodioscina, presentes em Brachiaria, podem ser responsáveis pelo dano hepático e consequentemente fotossensibilização. O objetivo deste estudo foi determinar o efeito da ensilagem de Brachiaria decumbens e Brachiaria brizantha e fenação de Brachiaria decumbens sobre a concentração de saponina esteroide. As amostras de Brachiaria ensiladas não tiveram concentrações detectáveis de saponina protodioscina depois de 24 dias de ensilagem. Assim como em Brachiaria decumbens, a concentração de protodioscina reduziu 48% nos três primeiros dias após a fenação e posteriormente manteve-se constante. Estes resultados sugerem que animais de produção, ao consumirem Brachiaria tanto como silagem ou feno, podem ter o risco de intoxicação por protodioscina reduzido.

Evaluation of peritoneal adhesions formation and tissue response to polypropylene - poli (2-hydroxyethyl methacrylate)-(polyHEMA) implant on rats' abdominal wall.

PURPOSE: To verify if the composit poli (2-hydroxyethyl methacrylate)-PolyHEMA/polypropylene mesh implanted in the female rat's abdominal wall could be suitable for the prevention of peritoneal adhesions, and for the evaluation of the tecidual response produced by this biomaterial. METHODS: Polypropylene meshes (Group PP, n=20) and polypropylene meshes coated with a layer of poli (2-hydroxyethyl methacrylate)-PolyHEMA (Group PH, n=20) were implanted on the abdominal wall of Wistar female rats. Ten animals from each group were submitted to euthanasia at 15 and 30 days of the postoperative period. RESULTS: The animals from the group PP presented visceral adhesions on the mesh surface, which was not observed in the ones from group PH. At the histopathological examination foreign body response was observed in both groups, whilst there was a greater intensity of inflammatory response in group PH on both moments. CONCLUSION: The poli (2-hydroxyethyl methacrylate) polyHEMA hydrogel associated to polypropylene mesh reduces visceral adhesion formation in rats, although it may be associated to greater inflammatory reaction.

Evaluation of peritoneal adhesions formation and tissue response to polypropylene - poli (2-hydroxyethyl methacrylate)-(polyHEMA) implant on rats' abdominal wall / Avaliação da formação de aderências peritoneais e da resposta tecidual ao implante de poli (2-hidroxietil dimetacrilato)-(poliHEMA) na parede abdominal de ratos

PURPOSE: To verify if the composit poli (2-hydroxyethyl methacrylate)-PolyHEMA/polypropylene mesh implanted in the female rat's abdominal wall could be suitable for the prevention of peritoneal adhesions, and for the evaluation of the tecidual response produced by this biomaterial. METHODS: Polypropylene meshes (Group PP, n=20) and polypropylene meshes coated with a layer of poli (2-hydroxyethyl methacrylate)-PolyHEMA (Group PH, n=20) were implanted on the abdominal wall of Wistar female rats. Ten animals from each group were submitted to euthanasia at 15 and 30 days of the postoperative period. RESULTS: The animals from the group PP presented visceral adhesions on the mesh surface, which was not observed in the ones from group PH. At the histopathological examination foreign body response was observed in both groups, whilst there was a greater intensity of inflammatory response in group PH on both moments. CONCLUSION: The poli (2-hydroxyethyl methacrylate) polyHEMA hydrogel associated to polypropylene mesh reduces visceral adhesion formation in rats, although it may be associated to greater inflammatory reaction.

OBJETIVO: Verificar se compósito poli 2-hidroxietil dimetacrilato (PoliHEMA) / tela de polipropileno implantado na parede abdominal de ratas seria adequado para prevenção de aderências peritoneais e avaliar a resposta tecidual desencadeada por este biomaterial. MÉTODOS: Foram implantadas telas de polipropileno - Grupo PP (n=20) e telas de polipropileno revestidas por uma camada de poli 2 (hidroxietil dimetacrilato)-PolyHEMA - Grupo PH (n=20) na parede abdominal de ratas da linhagem Wistar. Dez animais de cada grupo foram submetidos à eutanásia aos 15 e 30 dias de pós-operatório. RESULTADOS: Os animais do grupo PP apresentaram aderências viscerais na superfície da tela, o que não foi observado nos do grupo PH. Observou-se no exame histopatológico resposta tipo corpo estranho nos dois grupos sendo que no grupo PH houve maior intensidade de resposta inflamatória nos dois momentos. CONCLUSÃO: O hidrogel de poliHEMA quando associado à tela de polipropileno reduz a formação de aderências viscerais em ratos, embora possa estar associado à reação inflamatória mais intensa.

Use of chitosan membrane associated with polypropylene mesh to prevent peritoneal adhesion in rats.

The correction of wall abdominal defects often requires the use of implants such as polypropylene meshes. In spite of presenting good tissue acceptance, these biomaterials can migrate to adjacent viscera, promote enterocutaneos fistulas, tissue adherence and visceral erosions. In this work, the barrier effect of chitosan films associated with polypropylene meshes on adhesion formation experimentally induced in Wistar rats was evaluated. The animals were divided into two groups with 10 animals each. Animals in the CPP group were implanted with chitosan films associated with polypropylene meshes, whereas the ones in the PP group received only polypropylene meshes. After 8 days, the animals were submitted to euthanasia using CO(2) and a descriptive study focusing adhesion formation, visceral involvement with sutures and mesh peritonization was performed. Also, subimplanted material was collected for histopathology analysis. The results showed that the CPP group presented weak adhesions to the omentum over the stitch knots in eight animals. In all animals, the meshes were peritonized, not allowing their visualization after removing the chitosan films. In the PP group, six animals presented intestinal adhesions to the meshes and, in one of them, hepatic adhesion to the mesh was observed, besides omentum adhesion on more than 50% of the mesh area. The protective effect of chitosan films when sutured over polypropylene meshes, as well as no exacerbation of inflammation associated to the peritoneal lesions was statistically demonstrated. Therefore, chitosan films can indeed minimize the formation of peritoneal adhesions induced by polypropylene meshes in rats.

Reconstruction of thoracic esophagus with pediculated diaphragmatic flap in dogs.

PURPOSE: To verify whether pediculated diaphragmatic flaps were suitable to correct iatrogenic wounds in dog's esophagus injuries. METHODS: Seven dogs were submitted to resection of a segment of the esophageal wall, which was then corrected by suturing a pediculated diaphragm flap. Endoscopic evaluation of the esophageal wall was done forty days after the surgical procedure. RESULTS: Three animals died, one due to implant ischemia, caused by strangulation of the phrenic artery; other due to wound infection; and the last, due to mediastinitis. Scar retraction was observed, however, there was no stenosis, allowing the passage of a 9,8 mm probe with no difficulty. The limits between the implants and the native esophagus were indistinguishable, and the implant was covered by esophageal mucosa. CONCLUSION: The diaphragmatic flaps are suitable on the restoring of continuity in dog's thoracic esophagus.

Reconstruction of thoracic esophagus with pediculated diaphragmatic flap in dogs

PURPOSE: To verify whether pediculated diaphragmatic flaps were suitable to correct iatrogenic wounds in dog's esophagus injuries. METHODS: Seven dogs were submitted to resection of a segment of the esophagical wall, which was then corrected by suturing a pediculated diaphragm flap. Endoscopic evaluation of the esophagical wall was done forty days after the surgical procedure. RESULTS: Three animals died, one due to implant ischemia, caused by strangulation of the phrenic artery; other due to wound infection; and the last, due to mediastinitis. Scar retraction was observed, however, there was no stenosis, allowing the passage of a 9,8 mm probe with no difficulty. The limits between the implants and the native esophagus were indistinguishable, and the implant was covered by esophageal mucosa. CONCLUSION: The diaphragmatic flaps are suitable on the restoring of continuity in dog's thoracic esophagus.

OBJETIVO: Verificar se retalhos diafragmáticos pediculados seriam adequados para correção de defeitos iatrogênicos do esôfago do cão. MÉTODOS: Sete cães foram submetidos à ressecção de um segmento da parede esofágica, o qual foi corrigido por meio da sutura de um pedículo diafragmático pediculado. Um animal morreu devido à isquemia do implante causada pelo estrangulamento da artéria frênica, outro devido à infecção da ferida cutânea e outro devido a mediastinite. Aos 40 dias após o procedimento fez-se um exame endoscópico dos animais nos cães sobreviventes. RESULTADOS: Observou-se retração cicatricial sem repercutir em estenose, permitindo a passagem de sonda de 9,8 mm, sem dificuldade. Os limites entre os implantes e o esôfago nativo se apresentaram indistinguíveis e o implante estava recoberto por mucosa esofágica. CONCLUSÃO: Os retalhos diafragmáticos são adequados na restauração da continuidade do esôfago torácico do cão.

[Seringueira's latex membrane (Hevea brasiliensis) with and without polylysine 0.1% and marlex mesh for the reconstruction of iatrogenics abdominal wall defects in rats]. / Membrana de látex da seringueira (Hevea brasiliensis), com e sem polilisina a 0,1% e tela de marlex na reconstrução de defeitos iatrogênicos da parede abdominal de ratos.

PURPOSE: To compare seringueira latex membrane implant, with and without polylysine at 0.1% and marlex mesh on the repair of iatrogenic abdominal defects in rats. METHODS: A circular segment block of approximate three centimeters of diameter was sectioned out of the ventral abdominal muscle wall of 31 Wistar rats. The skin was preserved. The animals were divided into three experimental groups: only latex, latex and polylysine at 0.1%, and marlex mesh. Some rats underwent euthanasia at five and some at 120 days after surgery. Fragments of abdominal wall were collected and submitted at histopathologic analysis. RESULTS: The main alterations observed in groups treated with the latex membrane with and without polylysine were dehiscence (21 animals) and evisceration (two animals). The elimination of implant occurred at an average of 13.8 days. These animals presented fiber conjunctive tissue formation, similar to that observed in the group which received the marlex mesh. Other alterations noted were viscera-parietal adherences in all evaluated groups. CONCLUSION: The seringueira' s latex membrane, with or without polylysine 0.1%, when used on the reconstruction of abdominal defects in rats is eliminated at 13.8 days after its implantation, leaving a fiber base of reparation, similar to that observed after marlex mesh implantation.

Membrana de látex da seringueira (Hevea brasiliensis), com e sem polilisina a 0,1 por cento e tela de marlex na reconstrucão de defeitos iatrogênicos da parede abdominal de ratos / Seringueira's latex membrane (Hevea brasiliensis) with and without polylysine 0, 1 percent and marlex mesh for the reconstruction of iatrogenics abdominal wall defects in rats

OBJETIVO: Comparar o implante de membrana de látex da seringueira sem e com polilisina 0,1 por cento e tela de marlex na reparacão de defeitos abdominais iatrogênicos em ratos. MÉTODOS: Ressectou-se em bloco um segmento circular de aproximadamente três centímetros de diâmetro da parede muscular abdominal ventral de 31 ratos Wistar, preservando-se a pele. Os animais foram divididos em 3 grupos: grupo látex sem polilisina, grupo látex com polilisina 0,1 por cento e grupo marlex. Os animais foram sacrificados aos cinco e aos 120 dias após o procedimento cirúrgico. Fragmentos da parede abdominal foram coletados e submetidos à avaliacão histopatológica. RESULTADOS: As principais alteracões observadas nos grupos tratados com as membranas de látex sem e com polilisina 0,1 por cento foram deiscência (21 animais) e evisceracão (dois animais). A eliminacão dos implantes nos grupos tratados com látex ocorreu, em média, aos 13,8 dias. Nestes animais ocorreu a formacão de tecido conjuntivo fibroso, similar ao observado no grupo que recebeu o marlex. Outras alteracões notadas foram aderências viscero-parietais em todos os grupos avaliados. CONCLUSAO: A membrana de látex da seringueira com e sem polilisina a 0,1 por cento, quando utilizada para reconstrucão de defeitos abdominais em ratos é eliminada, em média, aos 13,8 dias após a sua implantacão, deixando uma base fibrosa de reparacão, similar à observada após a implantacão da tela de marlex.