相关实验视频

Updated: Jul 16, 2026

Using Chronic Social Stress to Model Postpartum Depression in Lactating Rodents
07:30

Using Chronic Social Stress to Model Postpartum Depression in Lactating Rodents

Published on: June 10, 2013

24.8K

解锁对牛和小牛压力指标的影响 牛-小牛接触系统中的牛和小牛压力指标的影响

Julie Føske Johnsen1, Johanne Sørby2, Sabine Ferneborg2

  • 1Section of Terrestrial Animal Health and Welfare, Norwegian Veterinary Institute, 1431 Ås, Norway.

JDS communications
|September 23, 2024
PubMed
概括

较长时间的,较早的逐步分离 (脱节) 对于乳牛,可能会减少最初的压力反应. 在分离过程中小牛的发声会受到年龄和牛奶摄入量的影响,但解方法对奶牛的影响有限.

更多相关视频

The Use of Traditional Fear Tests to Evaluate Different Emotional Circuits in Cattle12:08

The Use of Traditional Fear Tests to Evaluate Different Emotional Circuits in Cattle

Published on: April 22, 2020

8.6K
Restraint to Induce Stress in Mice and Rats03:48

Restraint to Induce Stress in Mice and Rats

Published on: December 6, 2024

1.1K

相关概念视频

Stress: General Loading Conditions01:15

Stress: General Loading Conditions

To grasp the intricacy of real-world conditions where multiple loads are applied simultaneously to a structure, one might visualize a section passing through a specific point within a body, aligned parallel to the xy plane. This section is subjected to various forces, including original loads, normal forces, and shearing forces.
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes.
Components of Stress01:23

Components of Stress

Stress analysis under multiple loading conditions is intricate, necessitating a comprehensive grasp of normal and shearing stresses. Consider a small cube at point O, subjected to stress on all six faces, visible or not. Normal stress components σx, σy, σz act perpendicularly to the x, y, and z axes. Shearing stress components τxy and τxz are exerted on faces perpendicular to these axes.
Interestingly, the hidden cube faces also experience these stresses, equal and opposite to those on the...
Stress Concentrations01:24

Stress Concentrations

Stress concentration is when stress intensifies near discontinuities such as holes or abrupt cross-sectional changes in a structural member. This localized stress can often surpass the average stress within the member. The stress distribution in flat bars, either with a circular hole or varying widths connected by fillets, can be determined experimentally using a photoelastic method. The results are based on ratios of geometric parameters like the ratio of the hole's radius to the smaller width...
Stress Concentrations01:13

Stress Concentrations

The concept of stress concentration is crucial for understanding how materials respond under bending stresses, particularly when there are irregularities or discontinuities in the material's geometry. Normally, stress in a symmetric member subjected to pure bending is assumed to be uniformly distributed across the entire cross-section. However, this assumption does not hold when there are variations in the cross-sectional geometry or the presence of notches and holes.
The stress concentration...
Physiological Foundation of Stress01:24

Physiological Foundation of Stress

Stress triggers a coordinated physiological response involving the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis. This dual activation ensures that the body is prepared for both immediate and prolonged stress management. The process begins with the perception of a stressor. This initial phase activates the SNS, leading to the rapid release of adrenaline (epinephrine) from the adrenal glands.
Role of the Sympathetic Nervous System
Adrenaline triggers the...
Stress Response System01:21

Stress Response System

The stress response system, also known as the fight-or-flight response, is the body's automatic physiological reaction to perceived threats. Hans Selye introduced the concept of General Adaptation Syndrome (GAS) to describe the predictable pattern of changes that occur in response to stress. GAS consists of three sequential stages: alarm, resistance, and exhaustion. This model helps explain how chronic stress can contribute to health problems.
Alarm stage
In the alarm stage, the body's initial...