Parâmetros da fermentação ruminal e concentração de derivados de purina de vacas em lactação alimentadas com castanha de caju / Ruminal fermentative parameters and concentration of purine derivatives in lactating dairy cows fed cashew nut

Avaliaram-se os parâmetros de fermentação ruminal e a concentração de derivados de purinas na urina de vacas leiteiras alimentadas com teores crescentes de castanha de caju na dieta. Foram utilizadas oito vacas Holandesas multíparas, sendo quatro fistuladas no rúmen, com produção média de 28±4kg de leite/dia. O delineamento experimental adotado foi o quadrado latino 4x4, com parcelas subdivididas para os parâmetros ruminais e duplo para determinação dos derivados de purina. Os tratamentos avaliados consistiram na inclusão de 0; 8; 16 e 24% de castanha de caju moída na porção concentrada da dieta. O comportamento do pH ruminal foi semelhante entre as dietas avaliadas segundo os tempos após alimentação. A concentração média de nitrogênio amoniacal foi 12,70mg/100mL de líquido ruminal. Os valores médios de acetato e butirato apresentaram padrão linear de resposta, contudo a relação acetato:propionato não foi alterada pela adição do coproduto. As excreções de derivados de purina na urina não variaram significativamente (P>0,05) com a adição de castanha de caju. A inclusão de castanha de caju não afetou os parâmetros de fermentação ruminal nem as concentrações de derivados de purinas; dessa forma, pode ser recomendada como alternativa potencial na alimentação de vacas leiteiras em lactação.

The parameters of rumen fermentation and the concentration of purine derivatives in the urine of dairy cows fed with increasing levels of cashew nut in the diet were evaluated. Eight multiparous holstein cows were used, being four rumen cannulated, with average production of 28±4kg of milk/day. The experimental design adopted was a 4x4 Latin square with split plots for the ruminal parameters and double for the determination of purine derivatives. The treatments consisted of the inclusion of 0; 8; 16 and 24% of cashew nut in the concentrate portion of the diet. The behavior of the ruminal pH was similar between the evaluated diets according to the time after feeding. The average concentration of ammonia nitrogen was 12.70mg/100mL of rumen fluid. The average values of acetate and butyrate showed a linear response, but the acetate:propionate ratio wasnot altered by the addition of the coproduct. The excretions of purine derivatives in urine did not differ significantly (P>0.05) with the addition of cashew nut. The inclusion of cashew nut did not affect ruminal fermentation parameters neither the concentrations of purine derivatives, so it can be recommended as a potential alternative for feeding dairy cows.

Pediatric urolithiasis in coastal Tunisia

We will try to show an outline of the clinical and biological characteristics of pediatric urolithiasis among Tunisian children in the coastal region. This retrospective study included 168 children below 16 years [100 boys and 68 girls] presented with urinary stones. Patients were reviewed in a multi-centric study with regard to age at diagnosis, sexual, historical, physical, laboratory, and radiologic findings. The physical and chemical analysis of stones was carried out by a stereomicroscope and infra-red spectroscopy respectively. Statistical analysis of data was carried out using software SPSS 11.0 for Windows. Statistical significance was determined using chi-square test. The sex ratio was 1.47. Clinical presentation of this pathology was dominated by abdominal pain [28%], hematuria [25.6%], dysuria [16.7%] and urinary tract infection [14.3%]. Stones were located in the upper urinary tract in 75.6% of cases. Of the urine cultures, 14.3% were positive. Whewellite is found more frequently in children stones than infants [P < 0.05] and was the main component in 46.4% of stone section and 55.4% of stone surface. Stuvite stones were more frequent among boys stones than girls' [11 Vs 2.9%] [P < 0.05]. The male prevalence of pediatric urolithiasis is less obvious in Tunisia. Calcium oxalate is the most frequent chemical compound in Tunisian pediatric urolithiasis

Mass spectra of some substituted purines, a high resolution study

The mass spectra of some substituted purines are reported and discussed. All compounds are thermodynamically stable and give an intense molecular ion, which undergoes different types of fragmentation depending on the nature of substituent. Fragmentation patterns involving McLafferty rearrangements are proposed