In goats (Capra) the growth and functional development of certain parts of the multi-chambered stomach continue during the first few months after birth. The aim of this research was to clarify morphofunctional changes in the kids abomasa and rumina and live weight gain during the first 8 weeks of life. Research was performed in two parts. In the first part (P1) we used Saanen breed kids which were all kept in the same conditions and in the second part (P2) we used Saanen breed kids which were separated in two groups with different feeding diets. In P1 the stomach contents of the goat kids were collected after slaughter (on day 1, 17, 25 and 30), weighed full and empty. The gastrohromoscopical method proved that in the newborn kids the area where the abomasal pH is 3.0 and lower is about 10% of the surface of the abomasum, but in age of three weeks it is composing 80% of the mucosal surface of the abomasum. In P2 were two groups – in the first group (MMG) kids which were fed with dairy (mother) milk and lived with mothers, the second group (MRG) kids were fed with milk replacer and lived separate from mothers. The stomach contents were collected after slaughter(at day 45 and 60).We confirm that the most important age of stomach development and kids growth in postnatal period are the first 45 days. During this period the most significant differences can be observed. On day 60 there are no significant differences (p is greater than 0.05) between MMG and MRG stomach development.

It is well known that secretion of gastric acid is regulated neurally by the stimulation of n.vagus and humorally by the activation of histamine H2 receptors in parietal cells. The purpose of the investigation was to clear up neural and humoral regulation mechanisms of gastric acid secretion in the postnatal ontogenesis of calves. Four calves from 5 to 14 weeks of age with chronical fistulae in abomasum have been investigated. Two electrode pH-probe has been used for measures. Atropine sulphate (0,06 mg kg*[-1) IV infusion) has been used to stop function of n.vagus, and cimetidine (0.16 mg kg*[-1) IV infusion) to block humoral regulation. The results clearly show that both, atropine sulphate and cimetidine, demonstrate some blocking influence on the HCL of abomasum in calves of different age.