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Review of human-animal interactions and their Impact on animal productivity and welfare.



Humans and animals are in regular and at times close contact in modern intensive farming systems. The quality of human-animal interactions can have a profound impact on the productivity and welfare of farm animals. Interactions by humans may be neutral, positive or negative in nature. Regular pleasant contact with humans may result in desirable alterations in the physiology, behaviour, health and productivity of farm animals. On the contrary, animals that were subjected to aversive human contact were highly fearful of humans and their growth and reproductive performance could be compromised. Farm animals are particularly sensitive to human stimulation that occurs early in life, while many systems of the animals are still developing. This may have long-lasting impact and could possibly modify their genetic potential. The question as to how human contact can have a positive impact on responses to stressors, and productivity is not well understood. Recent work in our laboratory suggested that pleasant human contact may alter ability to tolerate various stressors through enhanced heat shock protein (hsp) 70 expression. The induction of hsp is often associated with increased tolerance to environmental stressors and disease resistance in animals. The attitude and consequent behaviour of stockpeople affect the animals' fear of human which eventually influence animals' productivity and welfare. Other than attitude and behaviour, technical skills, knowledge, job motivation, commitment and job satisfaction are prerequisites for high job performance.
R E V I E W Open Access
Review of human-animal interactions and their
impact on animal productivity and welfare
Idrus Zulkifli
Humans and animals are in regular and at times close contact in modern intensive farming systems. The quality of
human-animal interactions can have a profound impact on the productivity and welfare of farm animals.
Interactions by humans may be neutral, positive or negative in nature. Regular pleasant contact with humans may
result in desirable alterations in the physiology, behaviour, health and productivity of farm animals. On the contrary,
animals that were subjected to aversive human contact were highly fearful of humans and their growth and
reproductive performance could be compromised. Farm animals are particularly sensitive to human stimulation that
occurs early in life, while many systems of the animals are still developing. This may have long-lasting impact and
could possibly modify their genetic potential. The question as to how human contact can have a positive impact
on responses to stressors, and productivity is not well understood. Recent work in our laboratory suggested that
pleasant human contact may alter ability to tolerate various stressors through enhanced heat shock protein (hsp)
70 expression. The induction of hsp is often associated with increased tolerance to environmental stressors and
disease resistance in animals. The attitude and consequent behaviour of stockpeople affect the animals fear of
human which eventually influence animals productivity and welfare. Other than attitude and behaviour, technical
skills, knowledge, job motivation, commitment and job satisfaction are prerequisites for high job performance.
Keywords: Animal welfare, Fear, Human-animal interactions, Productivity, Stress
Farm animals have undergone the process of domestica-
tion, a continuing genetic process aimed at modifying
the animals behaviour, anatomy and physiology to suit
mankinds specific needs [1]. Hence, domestic animals
should be adapted to man and captive environment.
However, many farm animals still perceive contact with
humans as an alarming predatory encou nter and sudden
changes in their physical and social environment as a
frightening experience [2,3]. In modern production sys-
tems, there are regular periods of contacts between
humans and animals such as during feeding and cleaning.
Animals may respond to tactile, visual, olfactory, gustatory
and auditory stimuli from humans. Even with considerable
automation in intensive farming, animals are still subjected
to some degree of human contact. The behaviour of
stockpersons is an important factor in determining the de-
gree of animals fear in humans and consequently the
quality of the human-animal interaction [4]. Fear for
humans is a major source of stress and may result is poor
productivity in farm animals. This subject has been exten-
sively reviewed previously [4-7].
The quality of human-animal interaction can have a
profound impact on many facets of an animals physi-
ology and behaviour. Interactions by humans may be
neutral, positive or negative in nature. Regular positive
contact with humans is desirable in bot h mammalian
and avian species [8]. On the other hand, farm animals
that were handled aversively were highly fearful of
humans, distressed and consequently their welfare and
productivity will be compromised [5]. There have been
considerable reports of attempts to alter the physiology,
behaviour and performance pigs, poultry and cattle
through regular positive contact with humans at both la-
boratory and farm levels [6,9]. The aim of this paper is
to review some of the research that shows impact of
human-animal interactions on the productivity an d wel-
fare of farm animals.
Institute of Tropical Agriculture, and Department of Animal Science,
Universiti Putra Malaysia, 43400, UPM, Serdang, Selangor, Malaysia
© 2013 Zulkifli; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (, which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.
Zulkifli Journal of Animal Science and Biotechnology 2013, 4:25
The concept of human-animal inter actions
According to Estep and Hetts [10], human-animal inter-
actions can be defined as the degree of relatedness or
distance between animal and humans. A relationship de-
velops between the stockperson and an animal in his /
her care. The relationship requires mutual individual
recognition. Animals may respond to tactile, visual, ol-
factory, gustatory and auditory stimuli from humans.
The quality of human-animal interactions will determine
whether the influence on an animals physiology and be-
haviour is desirable or otherwise [5]. There is the ques-
tion of whether animals can discriminate one human to
another human. Literature regarding the ability of farm
animals to recognise individual people is inconsistent. A
number of experiments suggested that farm animals re-
spond the same way to different people. Hemsworth [11]
compared the response of pigs to two different
stockpersons which differed markedly in their nature of
contact with pigs. The authors concluded that pigs were
unable to differentiate between different people and
aversive handling by one person made the animals fear-
ful of all people. Jones [12] indicated that chicks that
had been habituated to one person by a regimen of regu-
lar handling also showed less fear of similarly dressed
but otherwise dissimilar people. On the contrary, other
studies showed that pigs [13,14], laying hens [15] and
sheep [16] were able to recognise individual people.
Rybarczyk [17] suggested that dairy cows may recognise
people by their faces [17].
Modifying the stress and fear reactions in animals
through human-animal interactions
Stress can be defined as any disruption of an animals
homeostatic equilibrium requiring the animal to make
some responses to maintain its psycho-physiological in-
tegrity [18]. The life of a farm animal is constantly chal-
lenged by an array of factors that may evoke stress
responses. Overcrowding, extreme tempera tures, social
disruption, unfamiliar sounds, unfamiliar or uncaring
handlers, feed and water restriction, injection with anti-
gens, disease are common environmental factors that
may disrupt homeostasis. Biological reactions to stress
comprise changes in behaviour, neuroendocrine system,
autonomic nervous system and immune system [19]. In
many stressful events, the first line of defence is behav-
ioural response, which is biologically economic. When
the biological system fails to cope with the stressor(s)
and behavioural activity is suppressed, an animal de-
pends on the integrative capacities of nervous and endo-
crine systems. Regardless of whether the stimulus is
threatening or not, two distinct pathways inv olving
interlocking physiological reactions will be evoked. T he
first pathway comprises the sympathetic adreno-medullary
(SA) system that is responsible for the increase in the
synthesis and release of cathecolamines (adrenaline and
noradrenaline). T he SA system reaction is manifested by
immediate increases in blood pressure, muscle tone, nerve
sensibility, respiration rate and blood sugar. Although the
system may have dramatic physiological consequences, it is
short term. Activation of the hypothalamic-pituitary-
adrenal a xis is a longer adjustment to environmental
fluctuations. Sensory inputs cause the rele ase of
corticotrophin-releasing hormone form the hypothal-
amus. The neurohormone stimulates the anterior pitu-
itary gland to release adrenocorticotrophin hormone
that elicit s the adrenal cortex to relea se glucocorticoids
(cortisol and corticosterone). Glucocorticoids are known
to modulate immune response, shift metabolism, influ-
ence growth, and alter behaviour [20]. Changes in the cir-
culating levels of cortisol or corticosterone are routinely
used to measure an animals response to stress.
Stress and fear are not synonymous but the latter may
contribute to overall stress, particularly if the frightening
stimulation is intense, prolong ed or inescapable [21,22].
According to Jones [8], fear is an emotional (psycho-
physiological) response to perceived danger. Gray [23]
defined fear as a form of emotional reaction to a stimu-
lus that the animal works to termina te, escape from, or
avoid. High levels of fear not only represent a state of
suffering but they are also a powerful and potentially
damaging stressor. Two of the commonest and poten-
tially frightening events encountered by farm animals
are sudden chan ges in their social or physical environ-
ment and their exposure to people [8]. Animals probably
perceive a new unfamiliar environment with a degree of
uncertainty that acts as a psychological stimulus. In pigs,
short-term exposure to a novel environment indu ced
both behavioural and emotional reactions such as increased
locomotive activity and escape attempts, vocalization, and
as well as hormonal responses [24]. Novel environment is a
potent fear- and stress-elicitor in all animals. Zulkifli et al.
[25], and Zulkifli and Siti Nor Azah [26] noted elevation of
heterophil / lymphocyte ratios (HLR) 24 h following trans-
fer of chicks to new home cages. Translocation of chicks
from the hatcher to brooding cages or pens may result in
behavioural inhibition and panic [8].
The predominant response of the domestic fowl to
humans is thought to be one of fear [27]. Naive chickens
may perceive contact with humans as an alarming
predatory encounter. It is comm on for farm animals to
display fear-related behaviour in the presence of humans
such as withdrawal from or avoidance of humans, im-
mobility such as freezing or crouching [9,21]. Fear of
humans in farm animals can be measured by home cage
avoidance test, box plus experimenter and approachin g
human test [8]. The approaching human test is useful
for commercial poultry flocks raised in floor pens. An
experimenter can film the withdrawal responses of
Zulkifli Journal of Animal Science and Biotechnology 2013, 4:25 Page 2 of 7
chickens as he walks slowly through a chicken house.
Orientation away and withdrawal from the approaching
human may be equated with fear levels. It is well docu-
mented that procedures with high human involvements,
such as catching, loading and unloading can evoke both
stress and fear reactions which may compromise chick-
ens welfare [28-30]. Hemsworth and Gonyou [5] indi-
cated that pigs exhibited marked avoidance of humans
following imposition of daily negative interactions as lit-
tle as 15 to 30 s.
There is considerable report to suggest that regular
positive human contact is a powerful and reliable
method to dampen stress and fear reactions in pigs [31],
dairy cows [32], goat s [33], and poultry [26,34,35]. Al-
Aqil et al. [35] subjected broiler chicks to a pleasant
physical contact daily for 30 s from 1 to 28 d of age. The
authors found that those chickens had lower HLR,
plasma le vels of corticosterone (CORT), and shorter
tonic immobility (TI) duration than their neglected
counterparts following road transportation. Jones [8]
suggested that the benefit of regular handling was specif-
ically reducing birds fear of humans rather than through
any effect on their underlying fearfulness. However, dur-
ing transit chickens may be exposed to an array of
stressful and fearful stimuli including thermal extremes,
acceleration, vibration, motion, impacts, feed and water
deprivation, social disruption and noise [36]. Similarly,
Lyons [37] reported that early human contact not only
influenced behavioural responses to humans but also to
novel stimuli. Hence, the findings of Lyons [37], and Al-
Aqil et al. [35] showed that regular pleasant human con-
tact may attenuate nonspecific underlying fearfulness in
There is evidence that poultry are also sensitive to vis-
ual contact with humans [26,38,39]. Zulkifli et al. [34]
reported that visual contact procedure involving the ex-
perimenter standing in the centre of a pen (with no
attempted physical contact with birds) for 10 min twice
daily from 0 to 3 wk reduced fear and stress reactions to
handling and crating. Jones [38] demonstrated that vis-
ual contacts without tactile interaction was more effect-
ive in reducing fear of humans than picking up and
stroking the birds. Visual contact is obviously mor e feas-
ible and practical than physical contact in commercial
poultry flocks. There is, however, limited documented
work on visual contact with humans, on stress and fear
responses in non-avian species.
One of the earliest studies on the effect of early age
stimuli on physiological stress response was by Levine
[40] who reported that infantile stimulation through
handling elicited long lasting alterations of the adreno-
cortical function in rodents. When adults, these rats had
lower CORT both basally and during recovery, after
withdrawal of stressors than those that were not
handled, Gross [41] suggested that stimulation which
occur early in life while many systems of the animals are
still developing may have long lasting impact and could
possibly modify expression of their genetic potential.
Studies in pigs demonstrated that early handling during
the first eight wk of life increased the approach behav-
iour of pigs to an experimenter in a standard test from
10 to 24 wk of age [42]. Zulkifli et al. [34] compared the
effect of regular visual contact from 0 to 3 wk, 0 to 6 wk
and 3 to 6 wk in chickens subjected to crating at 42 d of
age. Chickens subjected to visual contact from 3 to 6 wk
showed longer TI durations and higher HLR in response
to crating than those interacted at other ages. Based on
these studies, it appears that early age human contact
may have long-term effects. On the other hand, Jones
and Waddington [43] reported that fear of humans in
20-day-old chicks was equally reduced irrespective they
were handled from 0 to 9, 10 to 18, or 0 to 18 d of age.
It is not clear whether the quality of human contact
experienced by animals at an early age can be modified
by subsequent pleasant or unpleasant interaction with
humans. This is critical under commercial setting be-
cause there will be variation both between and within
stockpersons in their behaviour toward farm animals.
Al-Aqil et al. [35] subjected chicks to either a combin-
ation of pleasant-unpleasant or unpleasant-pleasant
physical contacts from 1 to 14 d and 15 to 28 d of age,
respectively. Based on HLR and CORT reactions to road
transportation, the authors concluded that the benefits
of early age positiv e human contact can be modified by
subsequent unpleasant experience with humans. The au-
thors also indicated that chickens which had experienced
pleasant human contact early in life may perceive the
presence of huma ns as a signal for continuous positive
interaction. Hence, subsequent exposure to unpleasant
human contact may result in disappointment with con-
sequent elicitation of the physiological stress response.
Effect of human-animal interactions on animal
There is substantial evidence of a negative relationship
between underlying fearfulness and productivity in farm
animals [4,5]. Because positive interaction can reduce
fear of humans, such practice may enhance productivity
of farm animals. Gross and Siegel [44] postulated that
positive human contact may reduce the resources other-
wise required by animals to respond to their human asso-
ciates and that resources can be utilised for productivity.
In poultry, some authors [44-46] reported a significant im-
provement in weight gain and feed efficiency in positively
handled chickens. The enhanced disease resistance and
immune response in those studies could be associated
with the stress modulating effect of human contact. How-
ever, others demonstrated that positive tactile interaction
Zulkifli Journal of Animal Science and Biotechnology 2013, 4:25 Page 3 of 7
either had negligible [47] or negative effect [48] on growth
performance. Nature of the physical contact, breed and
age differences may have accounted for the discrepancies.
Zulkifli et al. [34] reported that regular visual contact, irre-
spective of age, had no effect on weight gain, feed intake,
FCR and mortality rates of broiler chickens. Zulkifli
and Siti Nor Az ah [26] compared the effe ct s of phys -
ical and visual contact s and showed only the former
was beneficia l in enha ncing growth performance. Phys -
ical contact which involved picking up and stroking
the chickens appeared to be more interactive than
visual contact in broiler chickens. In laying hens, however,
Barnett et al. [39] showed that regular visual contact
which reduced the subsequent avoidance behaviour of lay-
ing hens improved egg production.
According to Hemsworth and Coleman [26], fear of
humans may be considered as one of the major factors
for depressed growth and reproductive performance in
commercial pigs. Hemsworth et al. [31] subjected gilts
to either pleasant or unpleasant human contact three
times per week for 2 min in duration from 11 to 22 wk
of age. The authors noted gilts in the pleasant handling
treatment had significantly better weight gain but not
feed efficiency than those in the unpleasant handling
treatment. Unpleasant physical contact with humans re-
duced testicle size and delayed co-ordinated mating re-
sponse in boars when compared to those subjected to
positive handling by humans. In the similar study, gilts
in the unpleasant treatment showed a lower pregnancy
rate than those in the pleasant treatment. Work by
Paterson and Pearce [49], and Pearce et al. [50], how-
ever, suggested that the growth response of pigs
housed in groups wa s not affected by regular aversive
handling by humans. There is a possibility that pigs
raised in large groups may receive psychological pro-
tection from members of the group.
There have been relatively few human contact and
productivity studies in other farm animals. Rushen et al.
[51] showed that pleasant human contact had negligible
effect on milk yield but reduced some behavioural signs
of agitation in dairy cattle that were stressed due to
milking in an unfamiliar environment. The authors con-
cluded that human contact is not sufficient to reduce
neuroendocrine reaction to novelty / isolation stress.
Effect of human-animal interactions on animal health
The immune system, once considered an autonomous sys-
tem, is integrated with other physiological systems and is
sensitive to regulation of the brain [52]. Because human
contact may result alterations in brain physiology and
morphology [53] it is possible that immune response and
disease resistance will be affected. It is well established
that farm animals encountering challenging conditions
often show some degree of immunosupression [54-57].
Chronic activation of the hypothalamic-pituitary-adrenal
axis and the sympathetic-adrenal-medullary axis results
chronic production of corticosteroids and cathecolamines,
respectively. Lymphocytes, monocytes or macrophages
and granulocytes, exhibit receptors for corticosteroids and
cathecolamines, which can alter cellular trafficking, prolif-
eration, cytokine secretion, antibody production and cyto-
lytic activity [58].
Because fear is a potent stressor, reducing fear of
humans in farm animals through positive human contact
may enhance the health of animals. Other than poultry
there is a lack of information on the effect of human
contact on the immune response and disease resistance
in farm animals. Gross and Siegel [44,59,60] reported
that chickens habituated to humans through pleasant
contact were more resistant to Escherichia coli and
Staphylococcus aureus infections and had greater anti-
body production against erythrocyte antigens than those
that were ignored. Zulkifli et al. [34] indicated that regu-
lar visual contact from 0 to 3, an d 0 to 6 wk of age may
improve antibody production against Newcastle disease
vaccine. Similarly, Barnett et al. [39] showed that hens
subjected to regular pleasant human contact had im-
proved cell-mediated immune response to a mitogen
when compa red to the chickens that received negative
human contact. The benefit of human contact improving
disease resistance and immune res ponse could be a ssoci-
ated with its effect on modulating physiological stress
How do positive human-animal interactions improve
animal productivity and welfare?
There is the question of how positive human-animal
interaction can improve productivity and modify physio-
logical stress response of farm animals. At any particular
time, resources available to an individual are finite.
Hence, competition for resources between body func-
tions such as growth, reproduction and health will al-
ways occur [57]. The resources required to respond to
prolonged and severe stress may be significant. Gross
and Siegel [9] suggested that habituation to humans re-
duces the resources otherwise needed by the bird to re-
spond to subsequent human contact, and these resources
could be used either for coping with other environmental
stressors of for productivity.
Jones [8] suggested that regular human contact exerts
its effect by specifically reducing chickens fear of
humans. For example regular handling failed to influ-
ence chicks reactions to unfamiliar places and objects
[61,62]. On the contrary, Lyons [37] reported that early
human contact not only influenced behavioural reaction
of goats to human exposure but also a range of novel
stimuli. Al-Aqil et al. [35] showed that regular pleasant
human contact reduced stress and fear reactions to road
Zulkifli Journal of Animal Science and Biotechnology 2013, 4:25 Page 4 of 7
transportation in broiler chickens. Although road trans-
portation involved handling by humans, it is a multifac-
torial process which include feed and water deprivation,
noise, vibration, thermal extremes, social disruption,
crowding and restriction of movements [36]. Fluck [63]
suggested that handling of chicks decreased forebrain
aminobutyric acid (GABA) receptors and in vitro GABA
release from brain tissues. Hence, it appears that re-
duced chickens fear to humans is not the only possible
explanation for the benefit of a positive human-animal
interaction on farm animals.
When living organisms are exposed to thermal stresses,
the synthesis of most proteins is retarded but a group of
highly conserved proteins known as heat shock proteins
(hsp) are rapidly synthesized [64]. In a heat shocked cell,
hsp may bind to heat sensitive proteins and protect them
from degradation, or may prevent damaged proteins from
immediately precipitating and permanently affecting cell
viability. It has been documented that stressors other than
thermal stressors, for example feed restriction, confine-
ment in crates, transportation and social isolation [65-68]
may also elicit hsp 70 response in poultry. The induction
of hsp is often associated with increased tolerance to en-
vironmental stressors and disease resistance [65,69].
Al-Aqil et al. [35] subjected broiler chickens to either
pleasant or unpleasant negative human handling from
1 to 28 d of age. Following 3 h of road transportation,
the chickens had lower heterophil / lymphocyte ratios ,
shorter TI duration and greater hsp 70 expression
than those that were ignored or handled unplea santly.
Thus, it can be concluded that pleasant human contact
may alter ability to tolerate road transportation stress
through enhanced hsp 70 expression.
The impact of stockmanship on animal productivity and
The factors commonly emphasised to improve farm ani-
mals productivity are genetics , housing, nutrition, and
health. There is, however, less emph asis on the quality of
stockmanship. The way a stockperson carry out his or
her routine animal care tasks may contribute to the
overall relationship that animals have with humans and
determine the relationship is positive, negative or neu-
tral. Review of research in commercial pig and dairy
farms showed a significant sequential relationships be-
tween stockpeoples attitudes and behaviour towards ani-
mals and the fear of humans and productivity [70,71].
However, there is limited work in the poultry industry.
Cransberg et al [72] investigated the relationship between
stockperson attitude and behaviour, bird behaviour and
productivity in 24 commercial broiler chicken farms. Un-
like findings in pigs and dairy cattle, the authors failed to
find a relationship between stockpeoples attitude and be-
haviour. Although sequential relationships between human
behaviour, bird behaviour and production were noted by
the authors the magnitude of these relationships were not
as substantial as found in pig and dairy industries. The lack
of physical contact between stockperson and chickens and
the large number of chickens managed by the stockpeople
explanations for the results [72]. On the contrary, close
physical contact between stockpeople and animals is com-
The attitude of a stockperson holds about animals will
strongly influence their behaviour to wards animals [4].
The attitude and consequent behaviour of stockpeople
affect the animals fear of human which eventually influ-
ence animals productivity and well-being. Other than at-
titude and behaviour, technical skills, knowledge, job
motivation, commitment and job satisfaction are prereq-
uisites for high job performance. Hence, proper selection
and formal training of stockpeople are critical. Today,
many countries, including Malaysia, are facing labour
shortage in the agriculture sector. This may limit the
capacity to select high potential stockpersons. Another
possible limiting factor is the inadequate educational
background of the stockpeople which may restrict their
ability to be trained formally [4]. Thus, the content of
the training programme has to be easily comprehensible
by the target group. It is a lso critical that the animal
industry recognizes and apprec iates the stoc kpeoples
role in determining animal performance and welfare.
Better financial rewards and cle ar career pathway for
stockpeople would contribute to better motivation and
job performance.
The preceding discussion clearly highlights the oppor-
tunity to improve productivity and welfare of farm ani-
mals through positive human-animal interaction s. Most
of the pre vious findings on human-animal interaction
were based on laboratory studies. More on-farm studies,
particularly in poultry, are required before appropriate
operational strategies can be formulated for overall ease
and feasibility of implementation in commercial settings.
Factors such as genetic background, housing system,
prior experience and individual variation may determ ine
how an animal respond to human contact. The precise
physiological mechanisms underpinning the effect of
human-animal interactions on productivity and welfare
of farm animals are unclear, although changes in ability
to express heat shock proteins may be considered a pos-
sible route of action. The quality of stockmanship may
markedly influence the productivity and welfare of farm
animals. In intensive animal productions systems the
tasks of managing and monitoring intensively-raised ani-
mals have been increasingly replaced by the use of modern
technologies such as automation and surveillance cameras.
Such technologies are labour-saving but opportunities for
Zulkifli Journal of Animal Science and Biotechnology 2013, 4:25 Page 5 of 7
animals to interact with humans will be limited and
thus, may exacerbate their natural fear of humans. A
more regular visual contact with animals is necessary
to dampen underlying fearfulness and physiological
stress in farm animal. Hence, the attitude and behav-
iour of the stockpeople towards farm animals have to
be empha sised.
Competing interests
The author declares that he has no competing interests.
Received: 3 May 2013 Accepted: 4 July 2013
Published: 15 July 2013
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Cite this article as: Zulkifli: Review of human-animal interactions and
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Zulkifli Journal of Animal Science and Biotechnology 2013, 4:25 Page 7 of 7
... Positive contacts with humans can affect the physiological response to stress in animals, improving their immune response and thus, their resistance to diseases (poultry: [32]. However, at present there is a lack of studies concerning the effect of human contact on the health of other livestock species, including goats [33]. Alcedo et al. [34] suggested that positive human-animal interactions may be important in promoting goat health through gentle treatment during practices such as deworming or during situations where welfare is poor, such as disease, gestation and kidding, although these aspects were not directly investigated in this study. ...
... Furthermore, humans' characteristics, such as attitudes and empathy toward animals, should be taken into careful consideration, as they determine the behaviour of the stockpersons when working with the animals, and can therefore influence the quality of HAR [82]. Empathy, in particular, underpins attitudes towards animals and has a profound influence on animal fear towards humans, which in turn may affect their performance and welfare [33,82]. Other human characteristics that play an important role in this sense are represented by the propensity to work with animals, the knowledge and technical skills of farmers [82] and their commitment and job satisfaction [33]. ...
... Empathy, in particular, underpins attitudes towards animals and has a profound influence on animal fear towards humans, which in turn may affect their performance and welfare [33,82]. Other human characteristics that play an important role in this sense are represented by the propensity to work with animals, the knowledge and technical skills of farmers [82] and their commitment and job satisfaction [33]. Beaujouan et al. [83] also underlines that it is mandatory to consider the work context in which stockpeople operate, in order to fully understand how the HAR develops. ...
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There is consensus that the quality of the human–animal relationship (HAR) is relevant to guarantee appropriate levels of animal welfare. Given the impact that HAR may have on both goats and human beings, the aim of the present review is to elucidate: (1) how humans and goats communicate; (2) which are the factors affecting human–goat interactions; (3) how we can measure the quality of this relationship. The systematic review led to the selection of 58 relevant articles. Effective human–goat communication takes place by means of visual, tactile and auditory stimuli and, to a less extent, via olfactory and gustative stimuli. Goats have well-developed socio-cognitive abilities and rely on humans to get relevant information. A deep knowledge of goats’ communication means and socio-cognitive abilities may greatly help improving the human–goat relationship. Management practices (e.g., rearing methods, amount and quality of interactions), as well as genetic selection for suitable individual traits, may contribute to improving HAR. Several measures to assess the quality of HAR have been validated, including avoidance in the pen and at the feeding rack and latency to first contact. Finally, farmers’ attitudes and empathy with goats, as well as their motivation to work with animals, should be improved through appropriate training.
... The relationship between animals and humans is crucial due to regular and partly intense interactions in the daily routine of dairy farming. Various studies have shown that positive experiences with stockpersons directly reduce the cows' level of fear of humans, or that the presence of a familiar person can have stress-reducing effects during potentially negative procedures, such as veterinary treatment or restraint of the animals (reviews in [12][13][14][15]). ...
... Possibly, the positive effect of more frequent and intense animal care is mainly attributed to an earlier and better recognition of problems within the herd and to a faster implementation of improvements. In addition, increased human-animal contact of a neutral or positive nature also contributes to less cow fear behavior or physiological stress responses in human-animal interactions (reviewed in [12][13][14][15]), which was confirmed in a related study including the farms presented here within a broader sample [46]. In this and other previous studies, less avoidance behavior of cows towards humans in a standard test were, for instance, related to a closer ratio of cows per stockperson [46,63], increased daily contact time and stockpersons' ability to identify individual cows [64], and a combined variable including frequency of brushing, identification of cows, gentle handling, number of milkers and frequency of personnel changes [65]. ...
Full-text available
The affective state is an integrated aspect of farm animal welfare, which is understood as the animals’ perception of their living environment and of their internal biological functioning. The aim of this cross-sectional study was to explore animal-internal and external factors potentially influencing dairy cows’ affective state. For this purpose, qualitative behavior assessments (QBA) describing the animals’ body language were applied at herd level on 25 dairy farms. By means of principal component analysis (PCA), scores of PC1 (QBAscores) were determined for further analyses. From monthly milk recordings (MR) one year retrospectively, prevalences of udder and metabolic health impairments were calculated. Factors of housing, management, and human-animal contact were recorded via interviews and observations. A multivariable regression was calculated following a univariable preselection of factors. No associations were found between MR indicators and QBAscores. However, more positive QBAscores were associated with bedded cubicles or straw yards compared to raised cubicles, increased voluntary stockperson contact with the cows, and fixation of cows during main feeding times, the latter contributing to the explanatory model, but not being significant. These results underline the importance of lying comfort, positive human-animal relationship and reduction of competition during feeding for the well-being of dairy cows.
... Though livestock species have undergone some degree of selection to better tole the rearing/farming environment, each species still has to deal with a number of st triggers [42][43][44]. Apart from behavioral problems, this can also cause excessive morta and meat defects in pigs and poultry, e.g., PSE (pale, soft, exudative) or DFD (dark, f dry) meat [42,45,46]. In cattle, stress often results in reproductive disorders, and can e reduce milk yield/milkability; this may be related to inadequate care of the cow du milking by the worker as a result of which it feels fear [47,48]. ...
... Though livestock species have undergone some degree of selection to better tolerate the rearing/farming environment, each species still has to deal with a number of stress triggers [42][43][44]. Apart from behavioral problems, this can also cause excessive mortality and meat defects in pigs and poultry, e.g., PSE (pale, soft, exudative) or DFD (dark, firm, dry) meat [42,45,46]. In cattle, stress often results in reproductive disorders, and can even reduce milk yield/milkability; this may be related to inadequate care of the cow during milking by the worker as a result of which it feels fear [47,48]. ...
Full-text available
The welfare of animals, especially those kept in intensive production systems, is a priority for modern agriculture. This stems from the desire to keep animals healthy, to obtain a good-quality final product, and to meet the demands of today’s consumers, who have been increasingly persuaded to buy organic products. As a result, new sound-based methods have been pursued to reduce external stress in livestock. Music therapy has been known for thousands of years, and sounds were believed to improve both body and spirit. Today, they are mostly used to distract patients from their pain, as well as to treat depression and cardiovascular disorders. However, recent studies have suggested that appropriately selected music can confer some health benefits, e.g., by increasing the level and activity of natural killer cells. For use in livestock, the choice of genre, the loudness of the music and the tempo are all important factors. Some music tracks promote relaxation (thus improving yields), while others have the opposite effect. However, there is no doubt that enriching the animals’ environment with music improves their welfare and may also convince consumers to buy products from intensively farmed animals. The present paper explores the effects of music on livestock (cattle, poultry and pigs) on the basis of the available literature.
... The rationale is that in a study comparing the responses of pigs to two different stock persons with markedly different contact characteristics with pigs [26], the pigs were unable to distinguish the two, and one person's rude treatment made animals fear everyone. This is consistent with the conclusion that because regular positive human contact is a powerful and reliable way to alleviate stress and fear responses in pigs, the key to HAR is closely related to farmers [27,28] CONCLUSION These results can serve as basic data on sow welfare for farmers to successfully transition to group housing and flat floors. However, since this study was conducted on a controlled experimental farm, there may be limitations in drawing firm conclusions about the application of various breeding management methods and environments under diverse conditions according to the characteristics of the farmer. ...
In this study, considering the difficulties for all farms to convert farm styles to animal welfare-based housing, an experiment was performed to observe the changes in the behavior and welfare of sows when the slat floor was changed to a collective breeding ground. Twenty-eight sows used in this study were between the second and fifth parities to minimize the influence of parity. Using a flats floor cover, the flattening rates were treated as 0%, 20%, 30%, 40%, and 50%. Data collection was the behavior of sows visually observed using a camera (e.g., standing, lying, fighting and excessive biting behaviors, and abnormal behaviors) and the animal welfare level measured through field visits. Lying behavior was found to be higher (p < 0.01) as the flattening rate increased, and sows lying on the slatted cover also increased as the flattening rate increased (p < 0.01). Fighting behavior wasincreased when the flattening rate was increased to 20%, and chewing behavior was increased (p < 0.05) as the flattening rate increased. The animal welfare level of sows, 'good feeding', it was found that all treatment groups for body condition score and water were good at 100 (p < 0.05). 'Good housing' was the maximum value (100) in each treatment group. As the percentage of floor increased, the minimum good housing was increased from 78 in 0% flattening rate to 96 in 50% flattening rate. The maximum (100) 'good health' was achieved in the 0% and 20% flattening rates, and it was 98, 98, and 99 in the 30%, 50%, and 40% flattening rate, respectively. 'Appropriate behavior' score was significantly lower than that of other paremeters, but when the flattening ratio was 0% and 20%, the maximum and minimum values were 10. At 40% and 50%, the maximum values were 39 and 49, respectively, and the minimum values were analyzed as 19 for both 40% and 50%. These results will be used as basic data about sow welfare for farmers to successfully transition to group housing and flat floors.
... A good human-animal interaction is one welfare criterion (Blokhuis et al., 2010;Mellor et al., 2020). Animals subjected to aversive human contact (such as oral lesions resulting from bit use) may become fearful (Zulkifli, 2013) and such equipment as bits, tongue-ties, or tight nosebands used with marked or severe pressure may have negative effects on the horse-human relationship and prevent animals' natural behaviors (Farm Animal Welfare Council, 1979). Welfare problems in horses may in turn have negative consequences on humans and predispose them to accidents (Luke et al., 2022). ...
Full-text available
Bit-related oral lesions are a common and painful welfare issue in horses. Even though horses have been ridden and driven with a bit and bridle for 6000 years and bit sores have been described already in the 19th century in the veterinary literature, scientific reports on bit-related lesions and their risk factors in horses remain scarce. The aim of this thesis was to (i) determine the occurrence of oral lesions in the bit area in Finnish trotters and event horses after competitions, (ii) create a scoring system for oral lesions in the bit area and demonstrate different lesion types and locations with photographs, (iii) investigate risk factors for bit-related lesions in trotters and event horses, (iv) further investigate different stakeholders’ attitudes towards bit-related lesions in trotters. The rostral part of the mouth of 469 horses (261 trotters, 208 event horses) was examined systematically after a competition. Trotters were examined in 10 racing events in 2017 and event horses in 8 competition events in 2018–2019. Many horses had multiple lesions, and therefore, a lesion scoring system was created in which points were given to each lesion depending on its size, type (bruise or wound), and depth (superficial or deep). Points for each lesion were summed such that each horse received a total lesion score that reflected the overall lesion status. No acute lesions were found in 42 trotters (16%), and lesion status was mild in 55 trotters (21%), moderate in 113 trotters (43%), and severe in 51 trotters (20%). In event horses, no lesions were found in 99 horses (48%), and lesion status was mild in 45 (22%), moderate in 55 (26%), and severe in 9 horses (4%). The most common lesion location was the inner lip commissure. Lesions were also found in the bars of the mandible in front of the first lower cheek tooth, in the buccal area near the first upper cheek tooth, and in the outer lip commissures. Only a few horses had mild lesions involving the tongue and one horse in the hard palate. Although 109 event horses and 219 trotters had oral lesions in the bit area, none of the event horses and only six trotters showed external mouth bleeding. Additionally, one event horse and 26 trotters had blood inside the mouth or on the bit when it was removed from the mouth. Associations between a horse’s moderate-severe oral lesion status and potential risk factors were analyzed with multivariable logistic regression analysis. The association between bit type and lesion location was examined with Fisher’s exact test. Risk factors for moderate-severe oral lesion status in trotters were the use of a Crescendo bit, a mullen mouth regulator bit, or an unjointed plastic bit (model Happy Mouth) and female sex (mare). In event horses, the risk factors were thin (10–13 mm) and thick (18–22 mm) bits, female sex (mare), and other than pony breed. In both disciplines, unjointed bits were associated with lesions in the bars of the mandible. Single-jointed snaffle bits were the most common bit type in trotters and the least associated with moderate-severe lesions. In event horses, double-jointed 14–17 mm bits were most common. Bit thickness of 14–17 mm was the least associated with moderate-severe lesion status. However, these results may at least partly reflect driveability or rideability issues, and thus, rein tension differences because drivers/riders may change to distinctive bit designs if they have difficulty eliciting an appropriate response with rein cues. In the pilot questionnaire study, imaginary scenarios and photographs of lesions from horses’ mouths were presented to different stakeholders (veterinarians and race veterinary assistants, trainers, and others). They were asked in multiple choice questionnaires whether they allow the horse to start in the race, stipulate a health certificate before the next race, or remove the horse from the race. The association between stakeholder groups and their answers was examined with the Pearson Chi-square test. The results of this study indicated differences in attitudes towards bit-related lesions between stakeholder groups but also within a stakeholder group. This might reflect differences in conflicts of interests, moral values, empathy, or over-exposure to oral lesions. Not removing horses with severe oral lesions from the race may compromise horse welfare and society’s trust in the surveillance system. In this study, oral lesions in the bit area were common after a competition, although only few horses showed external bleeding. Oral examination and an oral lesion scoring system with an assistant recording the findings were suitable for field conditions and horses seemed to tolerate the examination well. Even though changing the bit to the bits least associated with lesions may be beneficial, horses with oral lesions might benefit from training modifications. Given the higher risk observed for mares in this study, mare oral health warrants special attention. Results of this thesis encourage adopting bit area monitoring as a new routine by horse handlers and as a welfare measure by competition organizers in order to minimize pain and negative experiences by early diagnosis and treatment of mouth lesions.
... Therefore, optimising the welfare of foals and young-stock requires careful consideration of the nature of interactions with the dam, timing of handling and the housing method. Evidence in several species indicates that positive or negative associations based on early experiences of learning can persist throughout the animal's life, with negative experiences increasing the fear behaviour, stress responses and associated negative alterations to the physiology (e.g., immunocompromise) [183][184][185]. ...
Full-text available
Equestrian sports, including racing (e.g., flat, steeple-chasing, harness or donkey derby); show-jumping; cross-country; dressage; polo; polocrosse; endurance; carriage driving; vaulting and hunting; are hugely popular in the UK, and they involve a significant number of people, both as participants and spectators, and tens of thousands of equids. In this paper, we discuss animal welfare as a complex and disputed issue, clarifying what the term means and how it can be measured. We review many aspects of welfare risk to equids used for sport, addressing issues encountered throughout their lives, including housing, feeding, veterinary intervention, shoeing, handling, training, breeding and equipment. This is followed by a unique exploration of the institutions and social processes influencing equine welfare. The institutional components comprise the rules of competition, the equids, attributes of the stakeholders and the space where participants strive to achieve a common purpose. We endeavour to untangle the most significant elements that create barriers or provide opportunities for equine welfare improvement. We expose the challenges faced by a broad range of stakeholders with differing ethics, attitudes and values. Evidently, there are many welfare risks to which equids used in sports continue to be exposed. It is also evident that significant improvements have occurred in recent times, but there remains a barrier to reducing the risks to an acceptable level. We conclude with recommendations regarding a process for change, involvement of stakeholders and management of knowledge to improve equine welfare that involves identifying and prioritising the risk factors and ultimately leading to interventions, further research and/or education.
... Rushen and Passillé (2017) stated that, the knowledge or technical competence of the stockperson can play a major role if it leads to improper choice of housing, poor feeding methods or lack of appropriate treatment of illness, and the quality and diligence with which routine tasks are done can be also be important. Zulkifli (2013) has shown that the way that animals are handled by people can have a major effect on their welfare. ...
Full-text available
The objectives of the study were to assess farm welfare conditions and the observance of welfare by cattle farmers in Ghana. The study applied field approaches to gather and analyze data. Data was collected from farms in the Northern, North East and Savanna regions. A total of three hundred and eighteen (318) cattle farmers were interviewed using semi-structured questionnaire. Observations and focus group discussions were also used to obtain data or verify some of the responses from the cattle farmers. Data collected was classified and summarized based on the information provided. The study found evidence that most farmers were concerned about their animal's welfare but did not place equal weight on the five freedoms of animal welfare. Farmers placed the most premium on freedom from hunger, malnutrition, and thirst (95%), and freedom from pain, injury and disease (90%). Farmers placed less premium on their animals' freedoms from fear and distress (50%), and freedom from physical and thermal discomfort (50%). The freedom to express normal patterns of behaviour (0%) was not considered by the farmers. Observance of animal welfare by cattle farmers was relatively below acceptable standards and government interventions are needed to improve animal welfare in Ghana.
... Nonetheless, a reduction in fear of humans can have important implications for both animal welfare and stockperson attitudes (see Hemsworth and Coleman [47] and Zulkifli [48]). Positive handling with increased visual human contact has shown to improve immune function [22,49] and production [50] in poultry. ...
Full-text available
Increased environmental complexity can improve animal welfare, depending on the re-sources provided and use by the animal. We provided chickens either with physical items that posed no biosecurity risk and were inexpensive (balls, chains, perches and rope) (P; n = 36) or additional visual human contact (10 min daily) (HC; n = 36) compared to farm-like standard control groups (C; n = 36) with 3 pens per treatment. Additional human contact reduced fear of humans at 35 days of age, but not general fearfulness. P birds required more inductions to induce tonic immobility compared to HC and C birds at 21 days of age. However, other indicators of fear (open field test and plasma corticosterone concentration) did not significantly differ. P birds favored the woodblock for resting, and the perch but preferred to sit underneath the perch rather than on top. When pecking items were not provided, C and HC chickens redirected their pecking behavior toward the litter. Overall, there was little evidence that our physical items improved the chickens’ behavioral time budget, fear, physiological stress or production. Additional human contact should be investigated in large scale experiments to ensure its effectiveness to reduce fear of humans on farm.
... Within commercial intensive poultry production, chickens are vulnerable to constant environmental challenges and management-associated stressors. Management-associated stressors and challenges include hatching without maternal contact, capturing, handling, transportation, extreme temperatures, social disruption, unfamiliar sounds and handlers, feed and water restriction (Zulkifli, 2013). These may cause stress (Frazer and Broom, 1990;Kannan and Mench, 1996;Bortolotti et al., 2008;Alm et al., 2014), leading to reduced performance and increased susceptibility to diseases (Goerlich et al., 2012) with secondary impacts on welfare (Carvalho et al., 2018). ...
Full-text available
Stressors are commonly encountered by all farmed species, including chickens, but the impact of these stressors on the animal and their productivity can be influenced by the environmental conditions in which they are kept. This study investigated the effects of dietary vitamin D3 (vitD3) and ultraviolet light (UVB) on growth performance, organ weight, serum corticosterone levels (CORT), serum 25-hydroxy vitamin D (25-OH-D3) status, gut histology, and welfare indicators of broiler chickens challenged with social isolation stress. One day (d) old Ross 308 broiler chicks (n = 192) were individually weighed, wing-tagged, and allocated to non-isolated (control) and isolated groups; control birds were never isolated, while isolated birds were subjected to regular sessions of social isolation for about 15-min periods over the course of 3 d a week for 2 weeks starting from d 10 (1.30 h total exposure) with inter treatment interval of 48 h. Birds were treated with either dietary vitD3 at 4,000 IU/kg (HD) or UVB light (UVB). The UVB lamp (24 Watt 12% UVB D3, 55 cm) with wavelength: 280–315 nm, intensity; 28.12 μW/cm2 hung 50 cm above the substrate was used for the broilers in all the treatment groups but were filtered to remove UVB in the HD group. Growth performance measure; body weight gain, feed intake, and feed conversion ratio were estimated at the end of starter (day 10), grower (day 24), and finisher periods (day 38). Broilers were feather and gait scored to measure welfare at 22/35 and 24/37 days of age, respectively. The selected birds were weighed and euthanized to obtain serum to determine 25-OH-D3 and CORT levels, GIT weights, and gut histology. Subjecting the birds to 2-week social isolation (for 15 min, three times per week) increased CORT levels but did not alter GP and 25-OH-D3 levels of broilers. However, UVB-treated broilers demonstrated better welfare, duodenal absorptive capacity, and reduced FCR compared to HD chickens. Results suggest some beneficial effects of UVB lighting on welfare indicators and the potential to support early life growth of commercial broilers reared indoors, which are often challenged with stressors.
This book brings together a range of scientific perspectives from biomedical research on stress and welfare, and assesses new approaches to conceptualizing and alleviating stress. While much of the focus in on conventional farm animals, there is also consideration of fishes, laboratory animals and zoo animals. The 30 contributors include leading authorities from North America, Europe, New Zealand and Australia. This book is invaluable for advanced students and researchers in animal behaviour, animal welfare, animal production, veterinary medicine and applied psychology. For more information see the CABI Publishing online bookshop (
Welfare, behaviour and stress during handling and transport of cattle, sheep, pigs, horses, deer and poultry, are discussed in 20 chapters of the book.
Heterophil/lymphocyte ratio (HLR) and tonic imobility durations were determined in broiler chickens which were pre-treated for 24 h with either 0 ppm (control) or 1200 ppm L-ascorbic acid in their drinking water. The birds were subsequently left undisturbed in their home cages (CTRL), crated and left stationary for 40 min (CO) or crated and transported for 40 min in an open truck (CT). Irrespective of pre-slaughter treatment, AA-supplemented birds had smaller HLR values (20 h following preslaughter treatment) and shorter TI durations. Significant effect of pre-slaughtering process on HLR and TI duration was evident with CT > CO > CTRL. While the number of inductions to induce TI was not affected by water treatment, the CT and CO birds were more susceptible to TI than their CTRL counterparts.
This chapter discusses catecholamine action and immunologic reactivity. The cells of the immune system are capable of responding to antigen in vitro, independent of most physiologic influences present in an intact organism, and the proposal of a physiologic role for catecholamines does not imply that they can replace such requirements as antigen presentation, T-cell recognition of major histocompatibility complex products, or interleukin production. The role of the catecholamines in the effector phase of immunity must also be dissected more fully. The report of unequal distribution of β-adrenoceptors among T and B cells and among T-cell subpopulations, in conjunction with the apparent heterogeneity of lymphocyte cAMP responsiveness to β-adrenoceptor and of lymphocyte responses following a rise in intracellular cAMP, underscores the importance of identifying adrenoceptors and determining the efficiency of intracellular effector mechanism coupling in purified cell populations throughout the course of an immune response. It was suggested that these immunomodulators, which are considered external to the immune system, may participate in a cooperative effort to fine-tune the response to antigen, restraining proliferative and other effector processes where necessary to ensure that the magnitude of the response is roughly proportional to the amount of antigen encountered and that the ongoing response is appropriately terminated.
Although many of the examples in this chapter have come from research conducted with the chicken, the authors' experimental animal, the implications are relevant to all forms of livestock and poultry that are husbanded in flocks and herds. In our opinion, the most important factor affecting the well-being of livestock and poultry is their relationship with their human associates. Kind care (socialization) has many well-being and production benefits. Socialized animals are easier to work with, have enhanced productivity, are more adaptable to adverse environments, are more resistant to diseases and develop better immunity. These factors make genetic selection easier. The responses of individuals within groups are also more uniform, thus reducing the number of animals needed for research. Further, socialization can be applied to large and small groups of animals as well as intensive and extensive production systems.
Human-animal interactions have a profound effect on farm animals and stockpeople alike. Training of stockpeople can improve livestock welfare and in turn productivity, and is a principle area of focus after improvements in genetics, nutrition, reproduction, health and housing have been addressed extensively. This volume explores new information on human-livestock relationships, their effects on both animals and handlers and the application of this knowledge particularly in relation to dairy cows, veal calves and poultry. Developments in knowledge of the relationships and their effects post-farm gate are discussed, providing a practical guide that will be a valuable resource for farm managers, researchers in the animal sciences, psychologists, ethologists and veterinarians. It will also benefit students of veterinary and animal sciences.Praise for the previous edition:'The book should take position in the libraries of people involved of animal production and especially in education and management of stockpersons'Livestock Production Science.