5 - Assessing Animal Welfare - Physiological Measures Flashcards
Briefly explain/show the sequence which drive the animal’s overall experiences.
- Gets sensory information from environment.
- Evaluates the sensory input in accordance of experiences or genetics, etc.
- Evaluation can be positive (e.g. pleasure), negative (e.g. fear), or neutral.
- Based from the emotion derived from evaluation the body will respond behaviorally and physiologically.
preserve the internal cellular environment which is essential for life
Homeostasis
pH level of blood in dogs and cats?
7.35 and 7.45
Second result of the adaptive process.
brain has new information against which to interpret future sensory input
main categories of physiological response that may contribute to homeostasis and allostasis
stress response, immune response (WBC Count), neurobiological responses, metabolic response
environmental effect on an individual which over-taxes its control
systems and results in adverse consequences, eventually reduced fitness
Stress, according to biology.
general term for the threats
Stressor
True or False.
Threats that cause stress response can be internal or external.
True.
Two main elements of stress response
- Autonomic Nervous System
- Hypothalamo-pituitary adrenal axis (HPA axis)
It provides the automatic control and regulation of tissues and key
organs including the heart, blood vessels, bowel, kidneys and bladder.
Autonomic Nervous System
It is part of the autonomic nervous system which allows the animal to engage in a situation after the brain evaluates a sensory input and gives rises to emotions.
Sympathetic Adrenal Medullary System
True or False.
The Sympathetic Adrenal Medullary System comprises the sympathetic nervous system and adrenal medullary system. In which sympathetic nervous system is neural and adrenal medullary system is hormonal.
True.
Hypothalamus innervates these structures.
a. the adrenal medulla
b. smooth muscle
c. the sphincter of the bladder
True or False.
The effect of the neuronal discharge by sympathetic neurons is generalized.
False.
Sympathetic neurons supply the smooth muscle within tissues therefore its effect is relatively targeted/specific.
When adrenal medulla neurons stimulates and releases adrenaline and noradrenaline, where does it go?
Into the bloodstream to circulate everywhere. Making its effect more generalized, in contrast with sympathetic neurons.
designed to enable an animal to escape an undesirable situation or
to make the most of a favorable one
SAM stress response
Give the three examples how SAM activation prepares the body for immediate action.
a. increased cardiac output
b. increased blood flow to the muscles
c. increased air intake
In SAM’s activation, what causes the increased cardiac output?
the sympathetic arm of the SAM system stimulates the sinoatrial node of the heart
What happens when there is peripheral vasoconstriction and contraction of the spleen?
increased blood flow to the muscle
The increased respiratory rate and relaxation of bronchioles in the lungs lead to?
Increased air intake
Stress response is brought to an end by what system?
Parasympathetic Nervous System
It balances the effects of the sympathetic adrenal medullary system.
Parasympathetic Nervous System
It stimulates the release of glucocorticoids into the blood.
adrenocorticotropic hormone (ACTH)
Corticotropic Releasing Hormone causes pituitary gland to release….
Adrenocorticotropic Hormone (ACTH)
Corticotropic Releasing Hormone (CRH) is released in what part of the brain?
Hypothalamus
It helps to cope with stressors.
Cortisol
Responsible for mobilizing energy stores in the short term, so that the
animal can run away from or fight off any threats, and therefore survive.
HPA axis
Glucocorticoids stimulate […] in the liver and suppress insulin secretion.
glycogenolysis
enable the animal to act rapidly to deal with the stressor e.g. by running away or fighting
raised/increase of glucose level
True or False.
The breakdown of glycogen to glucose increases glucose levels in the blood.
True.
There is sensory input to the brain. The brain evaluates it and, if appropriate based on past experience, the stress response is activated. That is, there is communication with the hypothalamus, which:
a. activates the SAM system
b. releases CRH which stimulates the anterior pituitary to release ACTH, which causes the adrenal cortex to release cortisol
True or False.
It is only natural that many events in an animal’s life can cause a stress response and this experience does not immediately concern animal welfare.
True. Because stress also allows the animal to make positive experiences for survival and avoid threatening situations.
When does exposure of animals to stressors become a concern to animal welfare?
When the animal’s body is stressed beyond the capacity of his/her emotional and physical systems to cope.
When it leads to adverse alterations in the body tissues which eventually becomes apparent as disease or in reduced production, stress response is called […]
maladaptive
A stressor where animals are pushed to produce beyond their metabolic or physical limits.
Over-exertion
related to confinement, such as when laboratory animals or pet birds are kept in small, barren cages without appropriate stimulation such as the presence of conspecifics
behavioral deprivation
another chronic stressor, e.g. with overcrowding in
pens, or mixing of unfamiliar animals, e.g. at markets
social stress
Prolong period of stress can cause disease. For example is chronic exposure to glucocorticoids, which reduces production of macrophages and monocytes and reduces circulating numbers of lymphocytes. Since lymphocytes help immune system fight foreign viruses and bacteria, what happens to an animal if their lymphocytes dramatically decreases?
It makes the animal more susceptible to infection.
An example of this is in young calves that are shipped to market, mixed with other calves during or after the sale, and then shipped on to their new farm. The continuous exposure to hours of stressors (transport, noise, mixing, novelty) makes them more likely to develop respiratory and enteric infections
Reduced Immunity
Signs of this may not be clinically obvious in the live animal, but can be detected post-mortem e.g. in the kidneys.
Hypertension
these can also be caused by malnutrition and parasitism as a stress response they may be caused by the catabolic effect of cortisol and adrenaline/noradrenaline in response to other stressors such as bullying by other animals.
Lack of growth and weight loss
can result in ulcers in the stomach and small intestine because the cortisol causes cell death with thinning of the mucosal lining
Chronic Exposure to cortisol
normal values can vary quite widely between individual animals within
a breed or species, and it is important to have a well-established normal range
Individual differences
repeated exposure to the same stimulus can lead to a decrease in catecholamine production on subsequent exposure to the stimulus
Habituation
repeated exposure to the same stimulus may not result in habituation of the adrenal response, and the response may be more marked, especially if the animal is then exposed to a different stimulus
Sensitization
enables animals to respond to foreign molecules and organisms
Immune Response
serves to neutralize invading organisms (e.g. bacteria) or substances (e.g. suture material)
Innate response
Innate response is mediated by what cells?
Neutrophils and Macrophages
True or False.
The innate response of the immune system is non-specific; it is not affected by vaccination.
True.
Meditated by Lymphocytes
adaptive immune response
provide cell-mediated immunity
T cells
produce antibodies
b cells
response to the proteins in foreign organisms or substances (e.g. viruses, pollens)
Humoral Immunity
can be modified by exposure to the foreign organism or protein and it responds to vaccination
adaptive immune response
group of chemical messengers involved in activation and operation of both parts of immune response (innate response and adaptive immune response)
Cytokines
Examples of Cytokines
Interleukin–2
Gamma-interferon (γ-interferon)
Give the tissues in the immune system.
bone marrow, thymus, spleen, lymph nodes and gut-associated lymphoid tissue
causes an increase in blood glucose through the breakdown of glycogen from the liver
Cortisol
results from the anaerobic metabolism of glucose, e.g. when an animal is running very fast to escape a threat, as part of the SAM response
Lactic acid
a ketone that is produced from the metabolism of fat when there
is not enough glucose available; can happen if animals are subjected to ongoing acute stress, e.g. in transport
Beta-hydroxy-butyrate
It is increased in preparation for running away, helping to ensure good oxygen delivery to the muscles, and is a result of activation of the SAM system and splenic contraction.
Haematocrit
It is the total red blood cell count.
Haematocrit
released into the bloodstream if animals are under extended physical stress
Muscle Enzymes
It is used to assess an animal’s metabolic response to a particular set of conditions like insulin and thyroid hormones.
Metabolic hormones
It is used to assess an animal’s metabolic response to a particular set of conditions like insulin and thyroid hormones.
Metabolic hormones
Why do changes in the immune system in response to stressors tend to make animals more susceptible to disease?
The effects on the immune system increase the animal’s risk of getting an infection. (e.g. mastitis in dairy cows)
important part of the initial response against respiratory pathogens
Neutrophils
most commonly associated with welfare changes, and therefore used in
welfare assessment
Endorphins
not so clearly associated with welfare changes, and therefore less used in assessing welfare. However, both are involved in endogenous pain
management, in the dorsal horn of the spinal cord and the brain.
Enkephalins and Dynorphins
Give the three functions of Opioids controlled by their release in the brain.
a. stress-induced analgesia
b. controlling the release of several hormones from the hypothalamus and pituitary glands which are involved in the stress response, including ACTH and prolactin
c. the perception of pleasurable stimuli, such as the enjoyment of food
a controversial surgical procedure involving the removal of wool-bearing skin around the hindquarters to reduce the risk of fly-strike.
Mulesing
produced by the pituitary gland and is involved in milk production
Prolactin
Dogs with generalized anxiety are reported to have much higher […….] than dogs who are less anxious, or normal.
prolactin levels
decrease in heart rate
Bradycardia
Examples of diseases due to prolonged exposure to stress:
a. Reduced Immunity
b. Hypertension
c. Enlarged Adrenal Gland
d. Lack of growth and weight loss
e. Reduced fertility
eliminated in the urine where they are not subject to acute fluctuations
Glucocorticoids
a non-steroidal anti-inflammatory drug
Ketoprofen
help to induce certain populations of T cells and overall cellular immunity
Cytokines
Examples of the adverse effects of stress on the immune system:
a. adverse imbalance in populations of T cells
b. inhibition of production of interleukin-2 and γ-interferon
involved in modulating emotions and the stress response
Prolactin
