Cathy Dwyer

SRUC, Animal and Veterinary Science, Faculty Member

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Farm characteristics in Slovene wolf habitat related to attacks on sheep

by Diederik Van Liere, Drago Kompan, Cathy Dwyer, Aleš Valenčič, and Nataša Siard

Applied Animal Behaviour Science, 2013

We aimed to characterize differences between sheep farms in wolf habitat in Slovenia that either ... more We aimed to characterize differences between sheep farms in wolf habitat in Slovenia that either suffered from wolf attacks (n = 30) or not (n = 30) during the pasture seasons 2008-2010. Main pasture season was from April until November. Median fenced pastures were 2.7 ha and herd size was 93 sheep. The three-year period contained 288 attacks, mostly occurring in May (36), and secondly peaking in October (23). 78% of all attacks occurred at night. Significantly fewer non-attacked than attacked farms had mixed herds (17% versus 40%). Wolves killed a median of 4 sheep per attack. If herds included goats, 2 goats could be killed in addition. Sheep were driven to a night facility before dusk by 43% of non-attacked farmers, and significantly fewer attacked farms (10%). Significantly fewer attacked than non-attacked farms kept sheep in closed night barns or a separately fenced night-area (20% versus 50%). Guarding dogs (usually 2 per herd) were kept by 53% attacked and 43% nonattacked farms. Average fence height was 115 cm and did not differ between attacked or non-attacked farms. 87% non-attacked farms had wire-mesh fences (either electric or not) instead of fences with horizontal single wires, which was significantly more than at attacked farms (61%). Significantly more attacked (89%) than non-attacked farms (60%) had electric fences (mobile or fixed, fixed ones could be combined with physical fences). In spite of farmers using electric fences, annual attack number was significantly higher at farms with a history of wolf attacks than at new farms (4 versus 1). Electric fences or guarding dogs as used in the study area proved ineffective: they did not prevent wolf attacks or reduce killing rates. Adoption of mesh instead of single wires, polarity alternation of live with ground wires in electric fences, and fences higher than 145 cm seem improvements. However, potentially, improved fencing could also prevent sheep from breaking out, if wolves have found ways to enter the fenced area, and might result in surplus killing. Alternative strategies are:

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Ewes Direct Most Maternal Attention towards Lambs that Show the Greatest Pain-Related Behavioural Responses

PLOS ONE, 2015

Although neonatal farm animals are frequently subjected to painful management procedures, the rol... more Although neonatal farm animals are frequently subjected to painful management procedures, the role of maternal behaviour in pain coping, has not been much studied. We investigated whether ewes were able to distinguish between lambs in pain and those that were not, and whether their behaviour altered depending on the severity of lamb pain. Eighty male lambs were allocated to one of 4 pain treatments within 24 hours of birth. Lambs were either handled only (C), bilaterally castrated with tight rubber rings (RR), as for RR but with the application of a Burdizzo clamp immediately proximal to the ring (Combined) or subjected to short scrotum castration (SSC) where the testicles were retained within the abdomen and only the scrotum removed. The behaviour of the ewe, treated lamb and untreated sibling where present (n = 54) were recorded for 30 minutes after treatment. Castration treatment increased the expression of abnormal standing and lying postures, specific pain-related behaviours (head-turning, stamping/kicking, easing quarters, tail wagging) and composite pain scores (P&amp;amp;lt;0.001 for all). The greatest expression of pain-related behaviours was shown by lambs in the RR group, which were the only group to show rolling responses indicative of severe pain, followed by the SSC group. Ewes expressed more licking/sniffing responses to the RR and SSC lambs than towards the Combined and C lambs (P&amp;amp;lt;0.05), and oriented most to RR lambs and least to C lambs (P&amp;amp;lt;0.001). Ewes with two lambs also directed more attention towards the treated than the untreated lamb (P&amp;amp;lt;0.001). The quantity of maternal care directed towards the lamb was positively correlated with the expression of active pain behaviours. The data demonstrate that ewes are able to discriminate between lambs in pain and those that are not, and that their response is increased with a greater severity of pain.

Chronic stress in Sheep: Assessment tools and their use in different management conditions

Animal welfare (South Mimms, England)

Chronic stress occurs when animals are unable to deal with a persistent stressor with species-typ... more Chronic stress occurs when animals are unable to deal with a persistent stressor with species-typical responses, or when several stressors are present concurrently. Chronic stress is most frequently considered in intensive systems, but it may also be a welfare concern for extensively managed species, such as the sheep. Here we review behavioural and physiological responses of sheep to experimentally induced chronic stressors to determine relevant indicators of chronic stress. Neuroendocrine responses to chronic stress are difficult to interpret because initial responses are followed by an apparent normalisation. Thus, cortisol or catecholamines may be at or below pre-stress levels during chronic stress, but this varies with different stressors. Chronic stress can also affect reproductive function, impair body and wool growth and meat quality, reduce immune function, and is associated with greater parasite burdens in sheep. Chronic stress induces alterations in behaviour patterns, pa...

How has the risk predation shaped the behavioural responses of sheep to fear and distress?

Animal welfare (South Mimms, England)

To use behaviours as indicators of stress it is important to understand their underlying causatio... more To use behaviours as indicators of stress it is important to understand their underlying causation. For a prey animal in the wild, such as a sheep, behavioural responses have evolved to evade detection and capture by predators. The behavioural responses of the wild ancestors of domestic sheep to the threat of predation are characterised predominantly by vigilance, flocking, flight to cover and behavioural inhibition once refuge has been reached. Some limited defensive behaviours are seen, mainly in females with young against small predators. Vigilance and flight distance are affected by the animal's assessment of risk and are influenced by the environment, social group size, age, sex and reproductive condition, as well as by previous experience with potential predators. Under conditions of stress, domestic sheep show similar behavioural reactions to wild sheep, although the threshold at which they are elicited may be elevated. This is particularly evident when comparing less sel...

Pen size and parity effects on maternal behaviour of Small-Tail Han sheep

Animal : an international journal of animal bioscience, 2015

The aim of this experiment was to study the effects of pen size and parity on maternal behaviour ... more The aim of this experiment was to study the effects of pen size and parity on maternal behaviour of twin-bearing Small-Tail Han ewes. A total of 24 ewes were allocated to a 2×2 design (six per pen), with parity (primiparous or multiparous) and pen size (large: 6.0×3.0 m; small: 6.0×1.5 m) as main effects at Linyi University, Shandong Province, China. Behaviour was observed from after parturition until weaning. All ewes were observed for 6 h every 5 days from 0700 to1000 h and from 1400 to 1700 h. Continuous focal animal sampling was used to quantify the duration of maternal behaviours: sucking, grooming and following as well as the frequency of udder accepting, udder refusing and low-pitched bleating. Oestradiol and cortisol concentrations in the faeces (collected in the morning every 5 days) were detected using EIA kits. All lambs were weighed 24 h after parturition and again at weaning at 35 days of age. The small pen size significantly reduced following (P<0.005), grooming (P&...

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Environment and the Sheep

Animal Welfare, 2008

... migrations prevented Home range and diurnal movements may be disrupted Predation and Disease ... more

Sheep senses, social cognition and capacity for consciousness

ABSTRACT

Behavioural development in the neonatal lamb: effect of maternal and birth-related factors

Theriogenology, 2003

The survival of the neonate relies on the integrated expression of appropriate behaviours from bo... more The survival of the neonate relies on the integrated expression of appropriate behaviours from both the mother and young. In precocious species, like the sheep, the speed with which the lamb stands and seeks the udder is related to lamb survival. In this study the effects of birth difficulty, lamb birth weight, ewe loss or gain in backfat from conception to delivery, ewe parity, litter size, and lamb sex on neonatal lamb behavioural development were investigated in over 500 lambs of two breeds (Scottish Blackface and Suffolk). Lambs that required assistance to be delivered were significantly slower to perform all neonatal behaviours than unassisted lambs (P&lt;0.001), and were less active over the first 3 days after delivery (P&lt;0.05). There were no effects of lamb birthweight that were not accounted for by the increased likelihood of requiring assistance in heavier birth weight lambs. Ewes that mobilised less body fat during their pregnancy produced lambs that stood and sucked quickly (P&lt;0.001), and were more active over the first 3 days of life. Lambs born to first parity ewes were slower to stand and suck than lambs born to experienced ewes (P&lt;0.001). There was an improvement in time taken by lambs to stand, seek the udder and to suck with each increase in ewe parity. Litter size had an additional retarding influence on the behaviour of multiple-born lambs that could not be accounted for by birthweight. In the Suffolk breed male lambs were slower to stand and suck than female lambs, this effect was not seen in Blackface lambs. These data demonstrate that lambs that require assistance at birth, even if they survive the birth process, lambs born to ewes that lose a lot of condition over pregnancy or first parity ewes, triplet lambs and, at least in some breeds, male lambs are slower to progress through the sequence of neonatal behaviours. These lambs are, therefore, at greater risk of not surviving to weaning.

The welfare of the neonatal lamb

Small Ruminant Research, 2008

... with a reduction in mammary development and weight ( [Mellor and Murray, 1985] , [Mellor et a... more

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Genetic and physiological determinants of maternal behavior and lamb survival: Implications for low-input sheep management

Journal of Animal Science, 2007

The relatively intensive supervision afforded many ewes at lambing time is a barrier to the devel... more The relatively intensive supervision afforded many ewes at lambing time is a barrier to the development of low-input sheep management systems. However, in some flocks, reduction in this level of supervision may initially affect lamb mortality and animal welfare. In this review, possibilities for optimizing behavioral interaction between the ewe and lamb are considered, with the goal of improving lamb survival without the need for high levels of human supervision. At birth, ewes show specific behavioral patterns (e.g., licking or grooming, low-pitched bleats, udder acceptance) that facilitate the transition of the lamb from pre- to postnatal life and that accompany the formation of an exclusive olfactory memory for the lamb. The lamb also performs a specific sequence of behaviors directed toward standing, finding the udder, and sucking. The successful accomplishment of these behavior patterns is vital for the formation of a strong attachment between both partners, and for lamb survival. The expression of maternal behavior in the ewe is affected by her previous maternal experience, by nutrition in pregnancy, by breed, by temperament, and, to some extent, by the behavior of her lamb. The maternal care expressed by a ewe at parturition is indicative of her behavior throughout that lactation and in successive pregnancies, suggesting an underlying basis to maternal care intrinsic to that ewe. Studies with Scottish Blackface and Suffolk ewes show that ewes expressing high levels of maternal care have elevated plasma estradiol in late gestation compared with ewes with poorer maternal care, and that circulating estradiol concentration is correlated with maternal behaviors. Although the genetic basis of maternal behaviors has still to be fully determined, there are possibilities of improving maternal behavior by selection, and a better understanding of the neuroendocrine processes underlying individual differences in maternal behavior may help in developing selection strategies. In addition, selection on lamb behaviors, which show some genetic basis, may also be a route to improve lamb survival. Because behavior of both the ewe and lamb is affected by environmental factors, appropriate management, through pregnancy and at parturition, will enhance the expression of maternal behavior and lamb vigor, and so contribute to improving lamb survival.

Introduction to Animal Welfare and the Sheep

Animal Welfare, 2008

Page 1. Chapter 1 Introduction to Animal Welfare and the Sheep CM Dwyer and AB Lawrence Abstract ... more

Does the anatomical location of a muscle affect the influence of undernutrition on muscle fibre number?

Journal of Anatomy

Nutritional restriction during muscle fibre number development invariably has a more detrimental ... more Nutritional restriction during muscle fibre number development invariably has a more detrimental effect on the biceps brachii than on the soleus. The difference may be due to the relative proportions of fibre types in the muscles or the anatomical location of the muscles. To distinguish between the effects of location and fibre type the biceps (fast, cranial and proximal), soleus (slow, caudal and distal), and extensor digitorum longus (EDL) (fast, caudal and distal) were examined from control and undernourished guinea pig neonates. A 40 % reduction in maternal intake resulted in a reduction in neonate body and muscle weights (P < 0.005), biceps (P < 0.05) and EDL fibre numbers (P < 0.005), but did not affect soleus fibre number. At birth the ratio of fast fibres to slow was 7.5 for the biceps, 7.0 for the EDL, and 1.5 for the soleus. The effect of undernutrition on muscle fibre number therefore seems to be a function of the fibre types in that muscle.

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The effect of maternal undernutrition on the growth and development of the guinea pig

Journal of developmental physiology

Fetal growth is known to be correlated with the size of the placenta and the exchange surface are... more Fetal growth is known to be correlated with the size of the placenta and the exchange surface area. Reduction in the growth of the materno-fetal exchange surface areas may be a mechanism by which the effects of maternal undernutrition on fetal growth are mediated. In the compact placenta of the guinea pig the exchange surface is equivalent to the peripheral labyrinth. The effect of a 40% reduction in maternal feed intake on the growth of the peripheral labyrinth was investigated in pregnant guinea pigs between gestational days 25 and 65. Fetal and placental weights were significantly reduced in the last trimester by 32% and 38% respectively (P &lt; 0.01). Placental efficiency in early gestation was significantly impaired in restricted animals but equivalent to ad lib. fed controls by the last trimester. The volume of the peripheral labyrinth increased as a percentage of the total placental volume with gestational age. Restricted placentae tended to be composed of a smaller volume of peripheral labyrinth tissue in early gestation. It is suggested that maternal undernutrition results in an impaired or delayed expansion of the peripheral labyrinth in early gestation causing a reduction in placental efficiency. By the last trimester the weight of the peripheral labyrinth of restricted animals was reduced by 33% (P &lt; 0.05). The weight of the peripheral labyrinth was also significantly correlated with fetal weight is limited by the size of the peripheral labyrinth in the later stages of gestation.

Maintenance of body temperature in the neonatal lamb: Effects of breed, birth weight, and litter size

Journal of Animal Science

To survive, the newborn lamb must be able to maintain body temperature and to stand and move to t... more To survive, the newborn lamb must be able to maintain body temperature and to stand and move to the udder to suck colostrum to fuel heat production. The objective of this study was to investigate whether neonatal lambs showing slow behavioral progress to standing and sucking also have an impaired ability to maintain body temperature. The time taken to stand and suck after birth, rectal temperatures, and blood samples were collected from 115 newborn single, twin, and triplet lambs of 2 breeds, Scottish Blackface and Suffolk, which are known to show variations in their neonatal behavioral progress. Blood samples were assayed for thyroid hormones, known to be involved in heat production, and cortisol, which plays a role in tissue maturation before birth. In addition, colostrum samples were collected from the 56 ewes that gave birth to the lambs, and assayed for protein, fat, and vitamin contents. Heavy lambs (more than 1 SD above the breed mean), Blackface lambs, and singleton or twin ...

Selection for easier managed sheep

Animal welfare (South Mimms, England)

Current alterations in the farm environment, such as a reduced number of farm workers, may mean t... more Current alterations in the farm environment, such as a reduced number of farm workers, may mean that sheep genotypes that are highly dependent on man for nutritional and reproductive success will experience poorer welfare within that environment. In the past 30 years, average flock size has doubled, and flocks of over 1,000 ewes managed by one stockperson are common. The reduction in the ratio of stockpeople to sheep affects animal welfare, with less time for tasks such as healthcare and inspection. It has also led to increased interest in the development of new genotypes that are better able to look after themselves. Selection and management of sheep to promote behaviours associated with survival, and selection of robust animals that require less human intervention for good welfare, are important breeding goals. As these animals will receive less inspection at close quarters, selection for resistance to disease will have significant animal welfare benefits. In addition, the develop...

Genetic parameters for birth difficulty, lamb vigour and lamb sucking ability in Suffolk sheep

Animal welfare (South Mimms, England)

This study investigates the genetic basis of lamb vigour (defined as neonatal lamb activity and s... more This study investigates the genetic basis of lamb vigour (defined as neonatal lamb activity and sucking ability) and lambing difficulty as potential traits to be included in selection programmes to improve ewe and lamb welfare. Scores for lamb birth difficulty, vigour and sucking ability were collected shortly after birth on 1,520 lambs born in 2006 in 19 different flocks that were members of the UK Suffolk Sire Referencing Scheme. Scores evaluated each trait on a scale of 1 to 4; 1 being no assistance given either during birth or to suck, or excellent vigour, through to 4 where a large degree of assistance was required, or poor vigour. Genetic parameters (heritabilities, genetic correlations) were estimated by fitting an individual animal model using ASREML. Variance components obtained from univariate and bivariate analyses were averaged to provide genetic parameter estimates. Heritabilities for birth difficulty and vigour were moderate but heritability for sucking ability was not...

Interactions between neonatal lamb vigour and faecal soiling at weaning in three breeds of sheep

Advances in Animal Biosciences, 2010

The Management of Sheep

The processes used to manage sheep in the broadest sense and the way these are perceived by the s... more The processes used to manage sheep in the broadest sense and the way these are perceived by the sheep will have a critical impact on the welfare of individual animals. While these impacts may be difficult to assess and more difficult to quantify, it is clear that the skilled stockperson has the ability to reduce the impact of some of the negative experiences that potentially aversive procedures – individual handling or transportation for example – may engender. There are additional challenges both to evaluate the perception of animals of long-term or chronic challenges in comparison with short-term, acute events and to reconcile the welfare of individuals with that of the flock as a whole. The importance of the human-animal relationship as a defined component of stockmanship is being more widely recognised. Selection and training of stockpersons will become increasingly important, yet identification and assessment of the complete range of desirable characteristics may not be easy. M...

The Economics of Sheep Welfare

This chapter aims to provide an introduction to some of the economic issues surrounding the welfa... more This chapter aims to provide an introduction to some of the economic issues surrounding the welfare of farmed sheep. Typically, ethical issues, or welfare indicators measured by natural scientists (physiological, physical and behavioural), gain precedence in discussion, and economic aspects are considered to be side issues. Moreover, economics is assumed, by some, to be a means of justifying profit generation at the expense of welfare – which it is not. Economics studies human behaviour as a relationship between ends and scarce means that have alternative uses. It is central to the achievement of acceptable levels of animal welfare, which are identified by the natural scientist and agreed through ethical debate. The actions of a wide range of individuals and groups influence the level of welfare that a sheep can experience during its life. These include farmers, hauliers, slaughtermen, consumers, non-consumers and government. Their roles and interactions are introduced in this chapt...

Administration of a NSAID (meloxicam) affects lying behaviour after caesarean section in beef cows

by Cathy Dwyer and Tamsin Coombs

Applied Animal Behaviour Science, 2014

Very little is known about the pain experienced by cattle following caesarean section and hence l... more Very little is known about the pain experienced by cattle following caesarean section and hence little consideration has been given to managing it. Thus the purpose of this study was to investigate activity-related behavioural changes in response to pain, by pre-emptively administering a long acting NSAID to beef cows undergoing caesarean section. One hundred and ten beef cows (55 primiparous, 55 multiparous) that underwent non-elective standardised caesarean section were recruited from eight French veterinary practices. Cows received pre-emptively either meloxicam (n = 63) or placebo (n = 47) according to a blind randomised schedule. Pedometers were attached to each cow's left hindleg and activity was monitored from 0 h (end of surgery) to 68 h post-partum. Time spent lying, number of steps and counts of lying bouts were calculated for the following periods: 0-8 h, 8-16 h, 16-24 h, 24-48 h and 48-68 h and analysed with a REML procedure.

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