Twenty-four-hour Variation of Plasma Leptin Concentration and Pulsatile Leptin Secretion in Cattle

  • Kawakita, Y. (Department of Animal Nutrition, National Institute of Animal Industry) ;
  • Abe, H. (Department of Animal Nutrition, National Institute of Animal Industry) ;
  • Hodate, K. (Department of Animal Nutrition, National Institute of Animal Industry)
  • Received : 2001.02.05
  • Accepted : 2001.05.07
  • Published : 2001.09.01


We conducted this study to investigate 24 h leptin profiles and to ascertain whether leptin secretion occurs in a pulsatile manner in cattle. Plasma leptin concentrations were measured every 10 min for 24 h in five Holstein steers aged 10 months. Simultaneously, feeding behavior was recorded every 5 min during this experiment. In two of the five cattle, leptin showed diurnal rhythmicity, which could be described by a cosine, with peaks between 15:00 and 16:00 and nadirs at around midnight. Pulsatile leptin release was quantified by model-free Cluster analysis. Plasma leptin showed a pulsatile pattern in all cattle, with an average number of pulses at 15 peaks/24 h. The daily number of pulses was not related to total time spent eating, ruminating or chewing. However, when divided into six 4 h time intervals, time spent ruminating was positively related with pulse number (p=0.05) in cattle showing no diurnal plasma leptin variation. These results suggest that cattle may have unique diurnal variation and pulsatile patterns of plasma leptin, differing from those of monogastric animals.


Leptin;Circadian Rhythm;Cattle