Changes in molecular species of pepsinogens in the development of the chick

Area of Science:

• Developmental biology
• Avian physiology
• Gastrointestinal development

Background:

• The development of digestive functions in newly hatched birds is crucial for post-hatch survival.
• Understanding the maturation of the avian stomach, particularly its peptic activity, is essential for avian nutrition and health.
• Pepsinogens are precursor enzymes to pepsin, critical for protein digestion.

Purpose of the Study:

• To investigate the developmental changes in peptic activity in the chick forestomach.
• To analyze the electrophoretic patterns of pepsinogens during the hatching period.
• To determine if these developmental changes are influenced by nutritional status.

Main Methods:

• Assessing peptic activity in chick forestomach extracts.
• Utilizing electrophoresis to analyze pepsinogen profiles.
• Comparing changes in fed versus starved newly hatched chicks.

Main Results:

• A rapid increase in potential peptic activity was observed at hatching.
• The electrophoretic pattern of pepsinogens shifted to the adult type concurrently with the increase in activity.
• These physiological and biochemical changes occurred irrespective of nutritional intake, even under complete starvation.

Conclusions:

• The maturation of chick forestomach peptic activity and pepsinogen profiles is an intrinsic developmental process occurring around hatching.
• Nutritional status does not appear to be a prerequisite for this critical digestive system development in newly hatched chicks.