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Animal Welfare Midterms Introduction to Animal Welfare Background ● For thousands of years, humans around the world have been concerned that animals are suffering ● Is this just anthropomorphism, that is attributing human characteristics to animals? No: We and many other species are sentient. Sentience ● One that has some ability to evaluate the actions of others in relation to itself and third parties, to remember some of its own actions and their consequences, to assess risk, to have some feelings and to have some degree of awareness – Broom, 2006 ○ That is, feelings that matter to the individual – Webster, 2011 ○ Consciousness of feelings – Mendi & Paul, 2004 ○ Not the same as self consciousness ● Sentient animals ○ Probably all vertebrates, some invertebrates, including e.g. squid, octopus, and possibly some crustaceans – Mellow et. al., 2009 ● The capacity to experience suffering and pleasure ● Implies a level of conscious awareness ● Can feel pain and suffer and experience positive emotions ● Studies show that animals can experience emotions ● Animal science is based on decades of scientific evidence from neuroscience, behavioral sciences and cognitive ethology Suffering ● One or more bad feelings continuing for more than a short period – Broom & Fraser, 2007 ● To suffer, an animal must be sentient Anthropomorphism ● Generally criticized ● Using human-based assessment may be useful first step – Webster, 2011 ○ E.g. surgery and pain ● Anthropomorphic assessments must be qualified with scientific evidence and information to meet and treat the individual animals’ needs Which sentient animals are vets concerned about? ● Species that we keep: domesticated and captive wild species ○ Husbandry ■ How to alaga, proper husbandry technique ○ Usage e.g. in research, farming, companionship; abuse ○ Transport, sale, markets ○ Slaughter, euthansia (also death of wild animals – pest control, hunting) Welfare and death Welfare ● concerns the quality of an animal’s life, not how long the life lasts (quantity) ● When an animal is dead he or she can no longer have experiences and his/her welfare is no longer a concern Death ● How an animal dies ● High mortality rate are indicative of poor welfare Although highly criticized, anthropomorphism can be helpful, but is not enough on its own Some animals can suffer ● Suffering – “one or more bad feelings continuing for more than a short period” (Broom & Fraser, 2007) ● Sentience – “ability to evaluate the actions of others in relation to itself and third parties, to remember some of its own actions and their consequences, to assess risk, to have some feelings and to have some degree of awareness” (Broom, 2006) ● Death is not a part of animal welfare, but the manner of death is, because it can be a source of suffering History ● India ○ Ahimsa – do not cause injury to any living being ○ Bishnoi tribe in rajasthan ■ Ecological philosophy for 500 yrs ■ Don't eat anything animal, and give 10% of harvest to wildlife ● China – confucianism ○ Because of one-ness with all beings, the suffering of animals is a source of distress in humans ● Europe ○ Ancient greece ■ Pythagoras and others – we are similar to animals so we shouldn't eat them ■ Stoics – animals aren't rational, therefore we don't need to worry about whether we are treating them fairly ■ Plutarch – animals may not be rational but we should still be kind to them ■ Porphyry – animals deserve moral consideration because they can feel distress ○ Britain in 18th and 19th centuries ■ Treatment of animals in britain had been very uncaring for many centuries ■ This became a concern because religious and other authorities believed humans should act virtuously
Animal Welfare Midterms Modern Agriculture ● In europe and north america, farming became more industrialized in 1950s and 1960s ○ Focus on production and efficiency → cheaper food for humans → better human health ○ Housing animals in large numbers → easier supervision but increased disease ○ Important welfare contribution from veterinary medicine → vaccinations, treatment One Health Initiative (2001) ● “Worldwide strategy for expanding interdisciplinary collaborations and communications in all aspects of health care for humans, animals and the environment” ● Shared risk to animals and humans from many diseases, environmental practices etc. that affect animal welfare and human welfare, such as avian flu: ○ spreads quickly in situations where animals are not well housed ○ when slaughtered control the disease, urgency may mean that animals are not handled or slaughtered humanely, and personnel may be at risk Vets and Animal Welfare Science ● Infectious disease prevention and eradication – 60 vaccines ● Importance of behavior ○ Clinical signs; pain ○ Behavior as an indicator of emotional state In the 21st Century ● Animal welfare science now a recognised discipline in vet schools around the world ○ Many research chairs and professorships, research groups and postgraduate training ○ Day 1 competency of new veterinary graduates (OIE, 2011c) ■ Explain animal welfare and related responsibilities ■ Identify and correct welfare problems ■ Know where to find information and local/national international standards of humane production, transport and slaughter ● Many people feel we have an obligation to animals (Broom, 2010) ● This is for different reasons, e.g. ○ Because animals have intrinsic value ○ Because animals have value to us, e.g. we eat them/they are useful to us ○ Because animals can suffer ○ Because the species is endangered ● Ethics and law Final Points ● Animal welfare is a complex concept ● Understanding it requires science (how different environments affect an animal‟s health and feelings, from the animal‟s point of view) ● Deciding how to apply those scientific findings involves ethics (how humans should treat animals: people worldwide have always been concerned about this) ● Enforcing those decisions in society involves the law (how humans must treat animals) Animal Welfare ● Still much disagreement about animal welfare because of different ethical values ○ “If animals are healthy, their welfare must be good” ● Complex concept with three areas of concern ○ Is the animal functioning well (good health, productivity, etc.) ○ Is the animal feeling well (absence of pain, etc.) ○ Is the animal able to perform natural/species-typical behaviors that are thought to be important to them (grazing) 3 Approaches When Considering Animal Welfare Physical ● Welfare of an animal is its state as regards its attempts to cope with its environment ● An animal is in a poor state of welfare when its physiological systems are disturbed to the point that survival or reproduction are impaired Mental ● Neither health or lack of stress nor fitness is necessary and/or sufficient to conclude that an animal has good welfare. Welfare is dependent upon what animal feels ● Feelings have adaptive value ○ Negative: escape immediate harm ○ Positive: promote long-term benefit – animals stay in situations that promote those feelings Natural Behavior ● In principle, we disapprove of a degree of confinement of an animal which necessarily frustrates most of the major activities which make up its natural behavior
Animal Welfare Midterms ■ By pairing a new stimulus with a familiar one, an animal can be conditioned to respond to the new stimuli. The conditioned response is typically a reflex ■ A conditioned response is a learned response or a response that is created where no response existed before. ■ Going back to the example of being bitten by a dog, the fear you have experienced after the bite is a conditioned response. ■ In operant conditioning, the animal repeats behaviors that have desired consequences and avoids behaviors that lead to undesirable consequences, ■ Examples ● bears, raccoons, dogs, and rats raid garbage cans because they have learned through trial and error that doing so leads to finding foods. ○ Imitation Types of Animal Behavior ● sexual ○ mounting ○ courting through songs and other signals ○ genital licking or releasing sperm ● maternal ○ This is an aspect of animal parental behavior the behavior of animal mothers towards their offspring and may include: nest building, egg sitting, suckling ○ feeding, either by lactation or gathering food, grooming young, and keeping the young warm. ○ improves the survival and well being of the offspring, thus is important for the success of the species. ● communicative ○ Ways animals transmit information to each other and other denizens of the animal kingdom ○ example ■ whale songs, wolf howl ■ frog croaks, ■ birds chirps ■ waggle dance of honeybee ■ vigorous waving of a dog's tail ○ 5 ways animal communicate ○ Animals communicate with each other in many different ways, they are: ■ body language ■ sound ■ smell ■ touch ■ chemical and electrical communications ○ can help animals find mates, establish dominance, defend territory, coordinate group behavior and care for the young ● Social ● feeding ○ (regulated by the feedback between appetite and satiety) is the response to the homeostatic mechanism that motivates an animal to acquire nutrients. ○ Applies to the behaviors related to obtaining and consuming food. ● eliminative ○ Eliminative behavior is the behavior associated with the elimination of feces and urine. ○ Cattle, sheep, goats and swine usually poop while standing up or walking. They also urinate while standing. ○ Animals in lush pastures normally drink less water when they eat dry feed. ○ Latrine behavior was to occur when horse ceases grazing and walks to an eliminative area to defecate and urinate. ● shelter seeking ○ Animals crowd together in snow and cold winds. Animals seek shelter from trees when it rains. ○ Cattle and sheep seek shady areas for rest and rumination if the weather is hot. ● investigative ○ Pigs,horses and dairy goats are highly curious, investigate any strange object, approach carefully, slowly, sniffing and looking as they approach. ● allelomimetic ○ a range of activities in which the performance of a behavior increases the probability of that behavior being performed by other nearby animals ○ can also be seen as an animal welfare indicator ■ e.g.if cattle do not have enough room to all lie down simultaneously then it indicates that there are not enough resources present and this can result in lameness of the animal that is forced to stand. ● maladaptive ○ refer to types of behaviors that inhibit an animal's ability to adjust to particular situations Behavior and Motivation ● Behavior motivated by internal cues is generally related to an animal's physical state (Nicol, 2011) ● Motivation can be to feed, to drink, to groom, to rest, etc. ● Motivation increases if the behavior is not performed ● Such behaviors must be permitted (e.g. calves and sucking; de Passillé & Rushen, 2006)
Animal Welfare Midterms ● Understanding the motivational basis of behavior makes it easier to deal with that behavior and improve an animal’s performance ● Punishing fear may make it works but some force may be required to stop true aggression ● External cues ○ Sight of predator ○ Smell of food ● External and internal cues ○ Social behavior ○ Conflicting motivation ● Importance of understanding motivation ○ Fighting vs. playing ○ Aggression ○ Affects handling ○ Advice to owners Central Role of Brain ● Evaluation of sensory input ○ Emotions, motivation, learning, expectations, anticipation ● Cognition: brain’s capacity to perceive, process, and store information ○ Sheep: spatial memory of grazing, expectations (Nicol, 2011) Emotion and Cognition ● Cognitive bias: influence of emotion on judgment, memory, etc. ○ People in a negative emotional state → focus on on negative memories and make more negative judgements than people in a positive emotional state Emotion and Motivation ● Negative emotions – pain, fear, frustration ○ Motivate relevant behavior that meet an immediate need ○ Injury: injury → pain → guarding behavior to protect the injured area ○ Seeing a predator: predator → fear → running away → survival ● Positive emotions – pleasure and excitement ○ Motivate behavior that is not needed urgently, for survival, but brings a long term benefit ○ Play: play → pleasure → play again → learn social and prey catching skills Genetics and Motivation ● Genetics ○ Gene mapping: behavioral differences are associated with differences in chromosomal regions ○ Feather pecking in poultry: lines with lower tendency to peck had higher egg production ○ Temperament in cattle: docility in the milking parlor Summary ● How to know if performing a particular behavior is important to animals ○ Behavioral repertoire ○ Motivation ○ Influence of emotions Measures of Behavioral Priority ● Animal works hard for the opportunity or resources to perform the behavior ○ Hens and nest boxes ○ Heifers and resting (13 hours) ● Animal develops substitute/abnormal behaviors if he or she cannot perform a desired behavior ○ Calves cross – sucking ○ Behaviors indicating frustration – if space/housing permits Substitute of abnormal behavior ● Stereotypies: repetitive behaviors, unchanging pattern, serve no obvious purpose ● Redirected behaviors: not abnormal but directed to an abnormal substrate – calves cross-sucking other calves ● Ex. pacing, rocking, swimming in circles, excessive sleeping, self-mutilation (feather picking and excessive grooming, and mouthing cage) ● Stereotypies are seen in may species including primates, birds, and carnivores ● Pacing – an animal walking in a distinct, unchanging pattern within its cage ● Walking can range in speed from slow and deliberate to very quick trotting Important behaviors ● Behavioral needs ○ Animals suffer if deprived of the opportunity to perform them ● Laying hens: nesting in a secluded place ● Pigs: rooting ○ Meaning of rooting behavior of pigs – pig uses his snout to push or nudge into something repeatedly ○ Pigs root for different reasons: for comfort, to communicate, to cool off, or to search for food (iron in soil for piglets) ● Calves: sucking ● Polar bears: walking long distances ● Hamters: burrowing ○ to hide and stay safe when asleep. – common when fresh bedding is put inside their cages. If the bedding is deep enough, you find your hamster has created tunnels Assessing Animal Welfare – Physiological Measures Environment/resources → brain evaluates → body responds → animal adapts and survives The Adaptive Process ● Animal adapts and survive
Animal Welfare Midterms digestive juices. Salivation may also be reduced or stop ● You will encounter many of these signs as a vet in practice. For example, when you hospitalize dogs and cats, some may not urinate or defecate for 24 hours or longer even though they have no physical problems in that area. instead, it is because of the SAM stress response. similarly. When you are doing a physical examination, you may check an animal's mouth for dryness to help you assess if he or she is dehydrated. an animal's mouth may feel dry simply because his/her brain has evaluated you as a threat, and the SAM system has been activated and is inhibiting salivation. ● The SAM stress response is designed to enable an animal to escape an undesirable situation or to make the most of a favorable one (both being considered acute stressors). Normally, when that is complete, the stress response is brought to an end by the parasympathetic nervous system. The parasympathetic nervous system balances the effects of the sympathetic adrenal medullary system. for example, when the stressful situation has passed, the parasympathetic nervous system ● reduces cardiac output through direct innervation of the sino-atrial node by parasympathetic nerve fibers; this stimulates a decrease in heart rate (bradycardia) ● enhances gut motility and intestinal secretions so that digestive activity can resume Effects of SAM Activation ● sympathetic stimulation of sinoatrial node ○ increased heart rate and increased strength of cardiac muscle contraction lead to increased cardiac output ● increased blood flow to key organs ○ peripheral vasoconstriction and contraction of the spleen ● increased air intake ○ increased respiratory rate and relaxation of bronchioles in the lungs ● non-essential bodily activities are inhibited Parasympathetic Nervous System ● regulates sam system ● reduces cardiac output ○ Bradycardia via effect on sinoatrial node Stress Response ● autonomic nervous system ○ sympathetic (adrenaline, noradrenaline) ○ parasympathetic (acetylcholine) ● hypothalamo-pituitary-adrenal (hpa) axis ● chronic exposure to stressors Cortisol ● mobilizes energy stores in the short term ● stimulates glycogenolysis in the liver and suppresses insulin secretion ○ increases glucose levels in the blood ● self-regulating system ○ gives negative feedback to the pituitary gland and the hypothalamus, thereby indirectly to the adrenal glands. this modulates the stress response as the animal's situation improves HPA Characteristics ● measure of acute welfare changes ● response not as immediate as the sam system ○ e.g. plasma glucocorticoids elevated 2- minutes after stimulation Welfare and Stress Response ● any event in the animal's life can create a stress response ○ should be adaptive ● experiencing stress is a natural response ○ only a concern when animal is stressed beyond ability to cope → pathology ○ chronic, inescapable bad conditions → maladaptive Welfare and Chronic Stress ● chronic stress can create pre-pathological states, e.g ○ reduced immunity ○ hypertension ○ enlarged adrenal gland ○ lack of growth ○ weight loss ○ reduced fertility ○ gastrointestinal ulcers Examples of measures of chronic stress response ● Glucocorticoids ● urine, saliva, milk ● acth stimulation stress in relation to welfare: practical examples ● capture of wild vicuñas for shearing ● effect of kennelling on dogs ● capture of wild sardines
Animal Welfare Midterms ● castration of farm animals ○ Piglets ○ dairy calves ○ water buffalo capture of wild vicuñas for shearing (arzamendia et al
● ~500 wild vicunas rounded up ● three methods used ○ people on foot ○ vehicles only (trucks, bikes) ○ combination: vehicles + people on foot ● measured stress response ○ direct measures (sam): heart rate, temperature, respiratory rate ○ blood samples (hpa and sam): glucose, cortisol, muscle enzymes ● behaviors, e.g. vocalizing, fighting capture of wild vicuñas for shearing (arzamendia et al
● cortisol: sex difference ○ females: captured by people on foot had higher levels of cortisol and more vocalizing than females captured by vehicles and people ○ males: captured by people on foot had lower levels of cortisol than males captured by vehicles and people ● cortisol: effect of captivity ○ cortisol values remained high, as did vigilance and alertness ● creatine kinase increased with longer captivity, especially in females effect of kennelling on dogs (hiby et al 2006) ● 26 dogs entering shelter ● urinary cortisol measured on ○ days 1, 2, 3, 5, 7 and 10 after admission ● half were from homes: half were either strays or returns to the shelter ● mean cortisol tended to decrease with time in the strays and returns, and to increase in dogs relinquished from homes capture of wild sardines (marcalo et al 2006) ● commercial purse-seine fishing, atlantic ocean portugal ● 174 sardines ● effect of time spent in the net ○ marked elevation of cortisol after one hour castration of farm animals ● castration — tissue damage ○ noxious sensory input ● brain evaluates input ○ emotions and feelings, e.g. pain and fear/frustration as they try to escape and cannot ● body responds ○ pain behavior, stress response Castration of piglets ● 84 piglets, five days old ● no clear effect on urinary corticosteroids catecholamines or growth. clear effects on pain behaviors for up to four days afterwards Castration of dairy calves (stafford et al., 2002) ● 190 friesian calves, up to six months old, four different castration techniques used ● simulated castration: no significant changes in cortisol caused by handling or lignocaine ● when castration was carried out without analgesia ○ all methods significantly increased cortisol to 56-101 nmol/l (comparison: acth response = 99 nmol/l ○ clamp castration: smallest cortisol response. analgesia eliminated it. however, castration not always successful ● surgical castration: local anesthetic did not reduce cortisol response. surgical castration: local anesthetic + ketoprofen eliminated cortisol response Castration of water buffalo (martins et al 2011) ● 21 calves: 7-18 months old ● compared methods of castration ○ surgical vs. clamp vs. no castration no analgesia measured cortisol ● Results ○ surgical castration: cortisol elevated for ~6 hours; pain on palpation at 48 hours ○ clamp: cortisol elevated for ~9 hours; no pain on palpation at 48 hours limitations of adrenal activity measures (1) ● do not indicate if animal's experience is positive negative or neutral ● increased activity from stress ● measurement itself may be stressful ● cost (e.g. implanted devices, some lab analyses) limitations of adrenal activity measures (2) ● individual differences e g ○ species and breed (mormede et al 2007) ○ sex (arzamendia et al., 2010) ○ experience (hiby et al 2006) ○ high vs. low' responders, e.g. ■ catecholamines in rats (livezey et al., 1985) ■ cortisol in zebu cows (solano et al., 2004) limitations of adrenal activity measures (3) ● habituation or sensitisation ○ depends on nature of the stressor ■ e.g. daily vs occasional exposure ● circadian rhythms, e.g. glucocorticoids limitations of adrenal activity measures (4) ● interpreting combined measures?
Animal Welfare Midterms ● tethered sows (zanella et al., 1996) ○ passive sows had higher m-receptor density than group-housed sows ○ stereotyping sows had low k- and m-receptors ○ Role of glucocorticoids? Dopamine ● Catecholamine ● various receptors (d1, d2, etc.) ● mood, locomotion, voluntary movement ● stereotypies, e.g sows in stalls, bar-biting: low dopamine prolactin ● pituitary gland ● modulates emotions and acute stress response ● hospitalized dogs (siracusa et al., 2010) ○ appeasing pheromone associated with lower plasma prolactin ○ appeasing pheromone not associated with dogs' behavior or welfare metabolic responses to stress glucose ● lactic acid ● Beta-hydroxy-butyrate ● Haematocrit ● muscle enzymes, e.g. creatine kinase ● hormones, e.g. insulin, thyroid hormones summary ● there are many physiological measures of welfare, and many reflect the stress response ○ stress response – sam and hpa ■ acute response to maintain homeostasis ■ chronic response may be maladaptive ● all responses can affect production ● need for other measures as well
