The anatomy and motor activities of the digestive organs were studied in fifty-two goatsy aged between sixty hours and fourteen months. The animals
were hand-reared and although provided with access to
solid fodder from the first, continued to be fed a
limited amount of milk beyond the usual time of weaning.
The abdomen was dissected in ten animals embalmed in
the standing position but, this apart, radiological
methods were employed• In addition to single films,
the movements were studied fluoroscoplcally and by
serial radiography, gr at reliance being placed upon
the latter as sup:lying an objective record. A number of cinefluoroscopic sequences were also obtained.The radiological anatomy and the post-natal
changes in tocography are described and the details
cannot conv niently be summarised. Development is
rapid especially in the first six weeks and a virtually adult condition is reached by three months or thereabouts. The following are the principal
observations on mechanics.On deglutition, fluids may be temporarily arrested at three points en route to the stomach and
may pass to and fro in the thorax before passing
the cardia.The rumen and reticulum develop rapidly after
birth, especially between the second and sixth weeks.
Both are active from the first weeks and an adult
pattern of behaviour a pears soon after the sixth
week. The ruminoreticular activity never acquires
great regularity and, in addition to the twostage reticular and the two- or four-stage ruminal
cycles commonly described, shows additional independent contractions of the major and blind sacs.Growth of the omasum is retarded until considerable amounts of solid fodder are consumed. Its
main activity is co-ordinated with reticular contraction when the upper pole dilates and fills: later
this part contracts and the expulsion of food is
assisted by constriction of the middle and distal
sections. Alternating contractions and relaxations
occur at other times also.The abomasum determines the abdominal topography
at birth but soon decreases in relative size. Its
parts and activities resemble those of the simple
stomach and both uninterrupted peristalsis and antral
systole occur: the latter is regarded as a modification of the former and predominates during the first
six weeks or so: later the movements are almost exclusively peristaltic. Activity is greatest
between the second and sixth week.The duodenal bulb exhibits systolic and other
less clearly defined contractions. The remainder
of the small intestine shows peristaltic, segmental
and other activities In complex combination. Peristalsis predominates in the proximal, more active,
part and gradually gives way to segmental activities
when the intestine is traced dietally.The large bowel continues the gradient of
activity. The caecum and colon show peristaltic
and (proximally) antiperistaltic contractions in
addition to several types of segmental contraction.The results as a whole emphasise the precocious
development of adult topography and behaviour and
demonstrate the close integration of structure and
function. It is suggested that the exclusive study
of the dead animal leads to a misconception of the
essential nature of visceral anatomy
