2000 Fiscal Year Final Research Report Summary
Factors Affecting Water Balance and Fecal Moisture Content in Suckling Calves Given Dry Feed
Project/Area Number |
10839020
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
動物臨床医学
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Research Institution | Azabu University |
Principal Investigator |
IRIKI Tsunenori Azabu University School of Veterinary Medecine, Laboratory of Nutrition, Assistant Professor, 獣医学部・栄養学研究室, 助教授 (60151693)
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Project Period (FY) |
1998 – 2000
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Keywords | dry feed / water balance / antidiuretic hormone / suckling calves / fecal moisture content / ketone bodies |
Research Abstract |
Holstein bull calves were used to examine factor affecting water balance and fecal moisture content in suckling calves given dry feed for 2 wk from 1 wk of age. In Experiment 1(n=20) calves, free access to concentrate and timothy hay decreased urine volume and increased apparent water retention, fecal water excretion, and fecal moisture content by 2 wk. In Experiment 2(n=20), free access to concentrate and hay from wk 1 increased reabsorption of water from renal tubules during wk 2. In Experiment 3(n=10), supplementation of 500g/d of milk replacer plus free access to concentrate and hay from wk 1 increased plasma antidiuretic hormone by 2 wk. Plasma antidiuretic hormone concentrations were highly correlated with plasma concentrations of acetate and ketone bodies. In Experiment 4(n=16) calves, apparent water retention and fecal moisture content during wk 2 were increased by free access to concentration from wk 1 but were not affected by rice straw as an inert bulk source. .In Experiment
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5(n=16) calves, the shift of water balance (decreased urine volume, and increased water retention and fecal water excretion) and elevation of fecal moisture content were greatest when calf stater and Sudangrass hay were fed in addition to liquid milk. Water retention was correlated positively with digestible DMI and negatively with urine volume. Fecal water excretion was highly correlated with fecal DM excretion. In Experiment 6(n=18), water balance and fecal moisture content during wk 2 were affected by free access to calf starter and hay from wk 1. Urine volume of calves fed dry feed and milk replacer was lower than that of calves fed only milk replacer, however, when water was available in addition to dry feed, urine volume was similar to that of calves fed only milk replacer. Fecal water excretion was highly correlated with water retention rather than with fecal DM excretion. Ruminal fermentation would be an important factor affecting both water balance and fecal moisture content in suckling calves given dry feed. In Experiment 7,8(n=15, However, though the administration in the rumen of the butric acid was made to increase plasma ketone bodies and ADH concentrations, the intravenous infusion of keton bodies did not increase plasma ADH concentrations. Less
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