Avaliação dos perfis minerais séricos, urinários e sedimentares de ovinos recebendo dieta calculogênica

Abstract

RESUMOA urolitíase obstrutiva em pequenos ruminantes é uma doença metabólica de etiologia multifatorial com distribuição mundial. A elevação da concentração urinária de solutos, minerais ionizados (cristaloides) que formam cristais insolúveis é citada por alguns autores como o fator mais importante. Assim, o conhecimento do perfil mineral dos animais submetidos a dietas calculogênicas e a composição química dos urólitos tornam-se ferramentas eficazes na prevenção da doença. Neste estudo, foram utilizados 14 ovinos hígidos, machos (não castrados), da raça Santa Inês, com idade aproximada de 90 dias, distribuídos em dois grupos (G1 -sem vitamina C e G2 -com vitamina C) e alimentados com dieta calculogênica. A análise dos perfis minerais, séricos e urinários revelou completo desbalanceamento na relação entre concentrações de cálcio, fósforo e magnésio, havendo elevação expressiva do fósforo e do magnésio e diminuição substancial do cálcio. Com isso, a análise bioquímica dos urólitos demonstrou que o cálcio esteve presente em 50% das amostras analisadas.Palavras-chave: doença de ovinos, mineral, trato urinário, urolitíase (Guimarães et al., 2007;Riet-Correa et al., 2008;Vinodhkumar et al., 2010). Em regiões áridas, onde o consumo de água é fator limitante, a incidência é maior. Embora apresente caráter esporádico, pode http://dx ABSTRACT Urolithiasis in small ruminants is a metabolic disease of multifactorial etiology with worldwide distribution. Increased urinary concentration of solutes, ionized minerals (crystalloid) that form insoluble crystals is cited by some authors as the most important factor. Thus, knowledge of mineral profile of the animals fed calculogenic diets and chemical composition of uroliths becomes an effective tool in preventing the disease. In this study, we used 14 healthy, male, non-neutered sheep, of the Santa Ines breed, aged approximately 90 days, divided into two groups (G1-without vitamin C and G2-with vitamin C) fed calculogenic diet. Analysis of mineral profiles in serum and urine revealed complete imbalance in

Low performance of vitamin C compared to ammonium chloride as an urinary acidifier in feedlot lambs

“…The large fluctuation in the pH for group G C , observed at M2 and M2c when compared with other groups, proved the inefficiency of oral vitamin C as a urinary acidifier and in the maintenance of acidic pH in sheep, corroborating the findings of other researchers who tested the dose of 1 g/animal/day (29,30) . Additionally, this fact was supported by the comparison with the effectiveness of ammonium chloride for urinary acidification in sheep in this study.…”

“…There was no statistical difference between the groups or times in relation to serum calcium (Ca) (Table 4), and the mean serum values were below the reference values (37,41) for sheep species, similar as that described by Maciel et al (29) in Santa Inês lambs fed a calculogenic diet.…”

“…The mean serum magnesium values (Table 5) were within the reference values (2.2 to 2.8 mg/dL) established by Kaneko et al (37) and Radostitis et al (41) , and varied from 2.27 to 2.63 mg/dL, although other authors have observed serum Mg concentrations of up to 3.33 mg/dL in confined lambs (29) .…”

“…Although the initial reduction in phosphorus was significant, vitamin C was not sufficient in acidifying urinary pH and was not effective in reducing the serum P level, even when used in combination with ammonium chloride. Maciel and collaborators (29) also observed an increase in serum P during the ingestion of an unbalanced diet in lambs supplemented with vitamin C.…”

“…There are no normal standards for the concentration of these electrolytes in urine, but other authors have studied the influence of different diets on the occurrence of urolithiasis in goats (5) and sheep (29) and described different values corresponding to the amount of the minerals in each dietary ingredient.…”