Daily rhythm of serum lipase and alpha-amylase activity in fed and fasted dogs.

The aim of the current study was to investigate the influence of feeding and fasting on the daily rhythm of serum lipase and alpha-amylase activity in dogs. Fourteen purebred Beagle dogs were housed in individual pens lined with wood shavings under a 12:12 light:dark cycle. The dogs were divided into 2 groups. Group A received normal feeding once a day, and group B was fasted starting 12 hr prior to the first blood collection. Water was available ad libitum. Blood samples were collected every 4 hr for 48 hr. Serum lipase and alpha-amylase activity were analyzed with standard kits by means of an ultraviolet spectrophotometer. Statistical analysis of the data was performed by 2-way analysis of variance and by single cosinor method. Results showed no statistical influence of feeding schedule on lipase and alpha-amylase and a robust daily rhythmicity of lipase and alpha-amylase in fed and fasted dogs. The current study could provide additional documentation of the structure of the dog circadian timing system and increase the necessary information related to the clinical approach to pancreatic diseases and to the therapeutic efficacy of timed administration of drugs or rations.