1990 Fiscal Year Final Research Report Summary
Physiological Studies on the Functional Alteration During Growth of Domestic Animals with Special Reference to Environments.
| Project/Area Number |
01480091
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
畜産学(含草地学)
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
SUGANO Shigeru Fac. Agr., The Univ. Tokyo, Prof., 農学部, 教授 (70111482)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MATSUI Kanji Fac. Agr., The Univ. Tokyo, Assist. Prof., 農学部, 助手 (50126166)
SAWASAKI Toru Fac. Agr., The Univ. Tokyo, Assoc Prof., 農学部, 助教授 (00012047)
TSUBONE Hirokazu Fac. Agr., The Univ. Tokyo, Assoc Prof., 農学部, 助教授 (30142095)
|
|---|
| Project Period (FY) |
1989 – 1990
|
| Keywords | Growth / Autonomic nerve / Behavior / Heart rate / Horse / Functional development / Pig / Goat |
|---|
| Research Abstract |
1. Alterations of behaviors and autonomic nervous tone in response to visual stimulus with a silhouette of a real size of horse were compared between pregnant and non-pregnant horses. The similar experiment was performed in Shiba-goats. The behavioral reaction was characterized as more nervous or alarming in pregnant animals than in non-pregnant animals. Analysis of heart rate and wave form (T-wave) of electrocardiogram suggested the prevailing sympathetic nervous tone in pregnant animals as compared with non-pregnant animals.
2. Alterations of the heart rate with and without autonomic blockade were traced through the growing period in rats and pigs. The parasympathetic tone of rats was low at 2 weeks of age and became higher during 2 to 4 weeks, whereas that of piglets at 2 weeks of age was highest at 2 weeks of age. In piglets, the net autonomic tone, expressed as a sum of the sympathetic and the parasympathetic tones, was maintained at the sympathetic side through the experimental period.
3. Cardiovascular functions (heart rate, femoral arterial pressure, right and left intraventricular pressure, left intraventricular dP/dt, aortic flow and stroke volume) before and after autonomic blockade were studied in piglets between 2 and 12 weeks of age. The intrinsic cardiovascular function of piglets during the growth process was regulated sympathetically in all the parameters except for stroke volume, which might be regulated autonomically through the Frank-Starling mechanism rather than autonomic nervous system.
4. The clear relationship was recognized between the growth and the litter size, sex constitution of sucklings or experience of parturition, based upon the analysis of past records on growth in pigs and Shiba-goats, and also experiments with rats.
|
