Regulation of the rabbit’s once-daily pattern of nursing: a circadian or hourglass-dependent process?

We have investigated the effect of pinealectomy of the pregnant ewe on the 24-h pattern of fetal breathing activity during late gestation. Fetal breathing movements were recorded during 24-h periods on 18 occasions in 5 pinealectomized ewes and on 24 occasions in 6 pineal-intact ewes between 120 and 145 days gestation. All ewes were fed once daily between 1000 and 1300 h and were kept under a light-dark cycle 12:12 h. There was no significant difference in the mean hourly incidence of fetal breathing movements between the pineal-intact (27.2 +/- 0.5 min/h) and pinealectomized (25.5 +/- 0.6 min/h) groups. However, there was a significant difference in the 24-h profiles of fetal breathing movements in the two groups. The peak incidence of fetal breathing occurred between 1900 and 2000 h in the pineal-intact ewes and between 1200 and 1300 h in the pinealectomized ewes. We conclude that maternal pinealectomy alters the daily pattern of a fetal behavioral pattern and that maternal melatonin may therefore provide the fetus with information about time of day.

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The effect of frequency of feeding on the flow and composition of duodenal digesta in sheep given straw-based diets

British Journal Of Nutrition ◽

10.1079/bjn19730010 ◽

1973 ◽

Vol 30 (1) ◽

pp. 87-94 ◽

Cited By ~ 14

Author(s):

F. Thompson

Keyword(s):

Particle Size ◽

Dry Matter ◽

Feeding Frequency ◽

Once Daily ◽

Daily Pattern ◽

Proximal Duodenum ◽

Frequent Feeding ◽

Effect Of Feeding

1. The effect of feeding sheep at two different frequencies (once hourly and once daily) on the flow of digesta, dry matter, and starch to the duodenum was assessed by fitting sheep with re-entrant cannulas in the proximal duodenum and giving them, at each feeding frequency, rations differing in the particle size of the roughage component.2. Frequent feeding resulted in a less variable daily pattern of flow of digesta and a significant increase (P < 0·01) in the total daily volume flowing to the duodenum. Altering the particle size of the ration did not affect the flow of digesta at either feeding frequency.3. The pattern of flow of dry matter followed very closely that of the flow of digesta, but there was a significant (P < 0·001) interaction between feeding frequency and particle size of the ration which affected the flow of starch to the duodenum. As a result, more starch entered the duodenum when both the frequency of feeding and the particle size of the ration were increased.

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Moral reasoning is the process of asking moral questions and answering them

Behavioral and Brain Sciences ◽

10.1017/s0140525x18002534 ◽

2019 ◽

Vol 42 ◽

Author(s):

Mark Alfano

Keyword(s):

Moral Reasoning ◽

Dependent Process ◽

Asking Questions ◽

Path Dependent ◽

Path Dependent Process ◽

Moral Questions

Abstract Reasoning is the iterative, path-dependent process of asking questions and answering them. Moral reasoning is a species of such reasoning, so it is a matter of asking and answering moral questions, which requires both creativity and curiosity. As such, interventions and practices that help people ask more and better moral questions promise to improve moral reasoning.

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The effect of bromocriptine on mammary-gland ultrastructure of hyperprolactinemic rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111136 ◽

1984 ◽

Vol 42 ◽

pp. 204-205

Author(s):

I.C. Murray

Keyword(s):

Mammary Gland ◽

Dopamine Agonist ◽

Alveolar Epithelium ◽

Mammary Glands ◽

Female Rats ◽

Control Group ◽

Cell Hyperplasia ◽

Once Daily ◽

Long Evans

In women, hyperprolactinemia is often due to a prolactin (PRL)-secreting adenoma or PRL cell hyperplasia. RRL excess stimulates the mammary glands and causes proliferation of the alveolar epithelium. Bromocriptine, a dopamine agonist, inhibits PRL secretion and is given to women to treat nonpuerperal galactorrhea. Old female rats have been reported to have PRL cell hyperplasia or adenoma leading to PRL hypersecretion and breast stimulation. Herein, we describe the effect of bromocriptine and consequently the reduction in serum PRL levels on the ultrastructure of rat mammary glands.Female Long-Evans rats, 23 months of age, were divided into control and bromocriptine-treated groups. The control animals were injected subcutaneously once daily with a 10% ethanol vehicle and were later divided into a normoprolactinemic control group with serum PRL levels under 30 ng/ml and a hyperprolactinemic control group with serum PRL levels above 30 ng/ml.

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3H-galactose and 3H-glucose incorporation into newly synthesized hepatic glycogen in control-fed rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143080 ◽

1986 ◽

Vol 44 ◽

pp. 292-293

Author(s):

J.E. Michaels ◽

S.A. Garfield ◽

J.T. Hung ◽

S.S. Smith ◽

R.R. Cardell

Keyword(s):

Biochemical Analysis ◽

Glycogen Synthesis ◽

Hepatic Glycogen ◽

Electron Microscopic ◽

Once Daily ◽

Tail Vein ◽

Tracer Dose ◽

Glucose Incorporation ◽

Wet Weight

3H-galactose (gal) and 3H-glucose (glu) were compared to determine which compound was preferable for pulse labeling newly formed hepatic glycogen. Control fed rats were used to achieve substantial and consistent levels of hepatic glycogen and to stimulate glycogen synthesis.Rats fed once daily for 4 hr achieved hepatic glycogen levels > 3% wet weight liver prior to injection by tail vein of a tracer dose of 3H-gal or 3H-glu. The rats were sacrificed 15-120 min later and liver was prepared by routine techniques for light (LM) and electron microscopic (EM) radioautography (RAG) and biochemical analysis.

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