[The effect of the energy intake of cows on the rumen metabolism studied using the excretion of allantoin in milk].
With two groups of dairy cows (A: 12 German Black and White- and 6 German Simmental Cows; B: 16 German Black and White- and 11 German Simmental Cows) allantoin concentrations of blood plasma (A) and milk (A and B) were analysed by HPLC. There exists a close correlation (r = 0.758) between allantoin concentration in blood plasma (370.6 +/- 79.1 mumol/l) and milk (474.1 +/- 78.9 mumol/l). The relation between milk yield and allantoin excretion with milk seems to be non-linear (r = 0.936). On the other hand there is a close correlation between energy intake with feed and allantoin excretion via milk (r = 0.885). In a further experiment the allantoin concentrations in blood plasma of 5 Angler steers were monitored for 24 h every second hour with feeding twice daily. There were remarkable fluctuations in the allantoin concentration from nearly 156 to 129 mumol/l. After that the rumen of the steers was emptied, while plasma concentrations were still monitored the same way as before. Concentrations of allantoin declined for about 55% to 65 mumol/l.
Rosskopf
R
R
Institut für Physiologie, Physiologische Chemie und Ernährungsphysiologie, Tierärztliche Fakultät der Ludwig-Maximilians-Universität München, Germany.
Giesecke
D
D
D000481:Allantoin / Q000032:analysis* / Q000097:blood; D000818:Animals; D002417:Cattle / Q000378:metabolism*; D002149:Energy Intake / Q000502:physiology*; D005260:Female; D008297:Male; D008892:Milk / Q000737:chemistry*; D012417:Rumen / Q000378:metabolism*
D000481:Allantoin
Untersuchungen an Kühen über den Einfluss der Energieaufnahme auf den Pansenstoffwechsel mittels der Allantoinausscheidung in der Milch.