Intoxicação experimental por nitrato/nitrito em bovinos suplementados com nitrato de cálcio encapsulado

• Autor(a) principal: Silva, Jordanna de Almeida e
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000006qcg
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/4295
• topic: Bovino; Uréia; CLINICA E CIRURGIA ANIMAL::CLINICA CIRURGICA ANIMAL

The objective of this research was to identify clinical and laboratory findings caused by the ingestion of calcium nitrate, encapsulated or conventional in different doses in cattle. Were used five bovines, cannulated, Nelore breed, male, with an average body weight of 500 kg were maintained during the entire experimental period in individual stalls with individual troughs for food and water. The experiment consisted of 75 days divided into five periods of 15 days. In each period the first 13 days were used for adaptation of the diet (Phase 1) followed by two days of collections (Phase 2). The experimental design was a latin square and the experimental groups were divided in the following way: not containing added nitrate in the diet (G1). 1.82% calcium nitrate and ammonium decahydrate without encapsulation in dry diet supplying 15% nitrogen (G2), 3.64% calcium nitrate and ammonium decahydrate without encapsulation in dry diet supplying 30% of nitrogen (G3), 2.58% calcium nitrate and ammonium decahydrate with encapsulation in dry diet providing 15% nitrogen (G4), 5.16% calcium nitrate and ammonium decahydrate with encapsulation in the dietary dry matter providing 30% nitrogen (G5). Data were analyzed using the R software (The R Development Core Team, 2010) in which was used the Tukey test by adopting a significance level of 5%. The animals were placed in contention tie stalls to perform physical examination. Then, were obtained blood samples for hemogram, fibrinogen, plasma protein, methemoglobin, nitrate and nitrite, blood biochemical, and ruminal fluid to measure pH, count protozoa and quantification of nitrite and nitrate. Changes in the hematological and biochemical examinations were nonspecific and punctual, while the methemoglobinemia was detected all livestock. The G3 group showed severe clinical signs requiring therapeutic intervention with methylene blue, which has been providing effective reductions in the levels of nitrate, nitrite and methemoglobin. Bovines to G2 and G4 groups have had similar clinical and laboratory results, not justifying the processing of nitrate font. The dose related to the G5 was efficient in preventing toxicosis nitrate / nitrite, however new research should be carried out to prove its cost / benefit.