(http://journals.cambridge.org/action/displayIssue?iid=779256)
(http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=779404&fulltextType=RA&fileId=S1357729806000439)
Vo Thi Kim Thanha1 and E. R. Ørskova2 c1
a1 Hue University of Agriculture and Forestry, 102 Phung Hung, Hue, Vietnama2 Macaulay Institute, Craigiebuckler, Aberdeen, AB15 8QH, UK
Abstract
In
experiment 1, three male calves of Vietnamese cattle and three
maleVietnamese swamp buffalo calves were weaned after receiving
colostrum and reared by bottle feeding of milk. During the 1st month the
animal did not have access to solid food. Urine was collected to
determine differences in endogenous excretion of purine between the two
types of animal. After that they were given access to equal amount of
solid food for 2 months to stimulate rumen development, urine was again
collected to determine the differences in purine excretion. In
experiment 2, the same animals were given milk mixed with purines in
three treatments (0, 1·7 and 3·4 g/day). The same animals were used in
experiment 3 for intravenous allantoin infusion, to test the effect of
purines themselves introduced into the plasma.The results showed that in
period 1 of experiment 1 there was no significant difference in purine
excretion between the two types of animal. The excretion being 0·65
mmol/kg M 0·75 for cattle and 0·69 mmol/kg M 0·75for
buffaloes calves, respectively. For period 2, after rumen development
there were significant differences between two types of animal. The
excretion from buffaloes (0·26 mmol/kg M0·75) being less than half that of cattle (0·69 mmol/kg M 0·75).In experiment 2 the regression of purine excretion mmol/day (y) was y=0·6279x+9·1496 for cattle calves and y=0·2618x+5·8594
for buffalo calves where x was the purine given.In experiment 3, from
each mmol of allantoin infusion, the recovery was about 0·70 in cattle
but only half (0·32) in buffaloes ( P<0·01).It is clearly
shown that the difference in purine derivative excretion occur only
after rumen development It is suggested that glomerular filtration rate
may be lower in buffaloes than cattle leaving more time in the blood
thus more time for recycling to the rumen and metabolized by bacteria or
the permeability from the blood to the rumen is greater in buffaloes
than cattle.
(Received July 07 2005)
(Accepted December 29 2005)
Key words
- buffaloes;
- cattle;
- purines;
- rumen
