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Biomedical subjects

F R Bell

Publications and source records attributed to F R Bell.

48 records · Page 3Linked to original sources
PubMed1973

Gastric emptying and secretion in the milk-fed calf.

1. For a few weeks, immediately post-natally, the abomasum of the ruminant stomach can be regarded as the analogue of the simple stomach for at this time food passes directly to the abomasum because of closure of the oesophageal groove.2. Using standard fractional and serial test meal techniques discussed by Hunt (1956) and adapted for use in the calf, abomasal emptying, acid and pepsin secretion have been examined. Phenol red was used as a marker to measure volume changes of the test meal.3. Abomasal emptying is exponential in character whether large or small volumes of fluid are instilled into the abomasum. The initial and end phase of emptying shows variable rates between animals.4. Glucose and lactose solutions inhibit abomasal emptying as well as acid production.5. Sodium chloride and sodium bicarbonate of low concentration, near isotonic with blood plasma, stimulate abomasal emptying but the bicarbonate is most effective. Hypertonic solutions of these salts inhibit abomasal emptying.6. Pepsin secretion in the abomasum of the calf is not affected by test meals of glucose, lactose, sodium chloride or sodium bicarbonate.7. These results shows a great similarity between the physiology of the abomasum of the milk-fed calf and the simple stomach. This suggests that the same duodenal receptors, discussed by Hunt & Knox (1968), which control gastric movement in man are also effective in controlling gastric emptying in the milk-fed calf.

Abomasum↗
PubMed1973

The effect of some molecules and ions on gastric function in the milk-fed calf.

1. The abomasum of the milk-fed calf has been examined using an adaptation of the Serial Test Meal method devised by Hunt & Spurrell (1951). The emptying process, acid secretion and pepsin secretion were studied.2. Using serial test meals of simple solutions instilled into the abomasum via a cannula, our investigation leaves no doubt that the osmolarity of the abomasal contents significantly modifies the rate of abomasal emptying.3. Hypotonic and isotonic solutions of sodium chloride and sodium bicarbonate increase abomasal emptying but bicarbonate is most effective.4. Increasing the concentration of solutes in the abomasal contents slows abomasal emptying. Sodium chloride, sodium bicarbonate, ammonium chloride and urea do not delay abomasal emptying until hypertonic concentrations are attained. Hypotonic solutions of potassium chloride, calcium chloride, glucose, lactose, hydrochloric acid and acetic acid delay abomasal emptying.5. The results obtained in the calf show that the abomasum is under restraint probably from duodenal receptors as is the simple stomach (Hunt & Knox, 1968) and that an osmoreceptor as postulated by Hunt (1956) is an important factor in this mechanism.6. Acid secretion is inhibited when hypertonic solutions are instilled into the abomasum.7. Pepsin secretion is not affected by simple solutions in the abomasum.8. Gastric function in the milk-fed calf appears to be controlled by mechanisms essentially similar to those already demonstrated in the simple stomach.

Abomasum↗
PubMed1966

Taste reception in the goat, sheep and calf.

1. The goat, sheep and calf have gustatory chemoreceptors which respond to salt, sweet, sour and bitter solutions, from which the afferent fibres pass centrally in the chorda tympani and glossopharyngeal nerves.2. Action potentials in the afferent gustatory nerves can also be detected when the tongue is irrigated with sodium bicarbonate, ethylene glycol, glycerine, and saccharine.3. Distilled water reduces the background activity in the isolated gustatory nerves, thus demonstrating the absence of fibres in ruminant ungulates of receptors which respond to stimulation by distilled water.4. The responses from the chemoreceptors, associated especially with the circumvallate papillae, are enhanced if the papillae are gently moved at the time of irrigation with sapid solutions.5. The chorda tympani is most responsive to salt and acid solutions while the glossopharyngeal is more responsive to sugars, quinine and acid.

Animals↗