Variations in the in sacco by product degradation in goats

P. CHAPOUTOT, D. SAUVANT
1987 Annales de Zootechnie  
= 11 : 1). At the beginning of the trial (pre-period) as well as from the 32&dquo! to the 42&dquo° day (main period) a balance period with faeces-and urine-sampling took place. A negative influence of the high K-supply in diets B and C on the Mg-metabolism was already observed in the pre-period. Moreover, animals with high K-and Na-supply (treatment C) showed an absolute and relative increase in Na-excretion in the urine. However except for the first balance day, the Na-urine excretion of
more » ... excretion of treatment B (high K-supply and correct Na-intake) corresponded to that of treatment A. Confirmed by the results of the main period, the negative influence of high K-levels on Mgmetabolism of cattle and sheep was also found in goats. Besides the apparent Mg-digestibility which tended to be lower (A : 38 % ; B : 33 % ; C : 30 the animals fed diets B and C also exhibited significantly lower Mg-retention (A : 0 g ; B : -0.09 g and C : -0.11 g/animal per day ; P < 1 °/ The extreme K-supply and the simultaneous wide K : Na ratio in diet B did not lead to an increased Na-excretion as it is sometimes reported in the literature. Concerning Naexcretion, there was no statistical difference (P > 5 %) between treatments A and B. The same applies to Na-retention (A : -0.54 g and -0.43 g/animal per day respectively in B). However, with a Na-retention of -1.57 g/animal per day there was a significant difference (P < 1 °/ ) between the animals of treatment C (high K-and Na-supply with correct K : Na ratio) and the remaining treatments. In the milk, the content of Mg (A : 0.14 g ; B : 0.14 g ; C : 0.13 g/kg milk), of K (A : 2.05 g ; B : 2.12 g ; C : 2.11 g/kg milk) and of Na (A : 0.42 g ; B : 0.43 g ; C : 0.42 g/kg milk) were not influenced by the varying supply of K and Na (P > 5 %). The same applies to the serum values for Mg (A : 1.11 mmol ; B : 1.05 mmol ; C : 1.07 mmol/I serum), K (A : 4.05 mmol ; B : 3.916 mmol ; C : 4.66 mmol/1 serum) and Na (A : 147 mmol ; B : 149 mmol ; C : 149 mmot/I serum). There were, however, highly significant differences (P < 5 %) in the course of the day. The stability of the K-and Na-serum values in the trial clearly showed that they are notas in other ruminantssuitable indicators for the estimation of the supply in the urine that might give more information on Na-intake, as there was a correlation of -0.87 (P < 1 %) between Naintake and this ratio in the present experiment.
doi:10.1051/animres:19870358 fatcat:pgtws4x6jjdq7dixe7fzpt47uu