Plasma amino acid indices and urinary 3-methyl histidine excretion in dairy cows in early lactation.
The experiment was performed on six cows from parturition to the 70th day of lactation. The highest milk yield, from 23 to 36 kg FCM daily, was reached between the 25th and the 50th day of lactation. The onset of lactation was accompanied with the intensification of muscle protein catabolism expressed by the highest urinary 3-methyl histidine excretion and body mass loss. In the same time the lowest plasma level of insulin, glucose, alanine, threonine, serine, proline, citrulline, ornithine, arginine, and urea was stated. The PDI intake covered PDI requirement at the beginning of lactation, 5th-10th day, but exceeded it in the period between 25th and 70th day of lactation. It caused the decrease of urinary 3-methyl histidine excretion and the increase of plasma urea cycle metabolites (ornithine, citrulline, arginine, urea) level.
D000596:Amino Acids / Q000097:blood*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002417:Cattle / Q000378:metabolism / Q000502:physiology*; D005260:Female; D006639:Histidine / Q000031:analogs & derivatives*; D007328:Insulin / Q000097:blood; D007774:Lactation; D008762:Methylhistidines / Q000652:urine*; D011247:Pregnancy; D013997:Time Factors; D014508:Urea / Q000097:blood
D000596:Amino Acids; D001786:Blood Glucose; D007328:Insulin; D008762:Methylhistidines; D006639:Histidine; D014508:Urea; C028118:3-methylhistidine