Effects of human-animal relationship on animal productivity and welfare
Daniel Mota-Rojas, Donald Maurice Broom, Agustín Orihuela, Antonio Velarde, Fabio Napolitano, María Alonso-Spilsbury
This is a literature review of the effects of humans´ relationships with farm animals on animal productivity and welfare, including the following topics: definition of the concept and description of different tests that have been developed to measure human-animal relationship (HAR). Temperament and tameness, which have been considered as farm animal characteristics that are important in HAR, as are stockperson attitudes. Some international farm animal welfare protocols are also described, together with negative and positive stimuli that affect farm animal welfare and productivity. In addition to some factors affecting the quality of HAR. We conclude that even with improved precision farming and automation: a) a good HAR is still fundamental to improve farm animal welfare with associated health and production benefits and b) with the numerous tests assessing fear of humans, many are not commercially applicable.
Adler F, Christley R, Campe A (2019) Examining farmers' personalities and attitudes as possible risk factors for dairy cattle health, welfare, productivity, and farm management: A systematic scoping review. Journal of Dairy Science 102:3805-3824.
Al-Aqil A, Zulkifli I, Hair Bejo M, Sazili AQ, Rajion MA, Somchit MN (2013) Changes in heat shock protein 70, blood parameters and fear-related behavior in broiler chickens as affected by pleasant and unpleasant human contact. Poultry Science 92:33-40.
Andersen IL, Berg S, Bøe KE, Edwards SA (2006) Positive handling in late pregnancy and the consequences for maternal behavior and production in sows. Applied Animal Behaviour Science 99:64-76.
Arias JLP, Špinka M (2005) Associations of stockpersons' personalities and attitudes with performance of dairy cattle herds. Czech Journal of Animal Science 50: 226-34.
AWIN (2015a) AWIN Welfare Assessment Protocol for Sheep. doi:10.13130/AWIN_sheep_2015.
AWIN (2015b) AWIN Welfare Assessment Protocol for Horses. doi: 10.13130/awin_horses_2015.
AWIN (2015c) AWIN Welfare Assessment Protocol for Goats. doi:10.13130/AWIN_goats_2015.
Barnett JL, Hemsworth PH, Jones RB (1993) Behavioral responses of commercially farmed laying hens to humans: evidence of stimulus generalization. Applied Animal Behaviour Science 37:139-146.
Barnett JL, Hemsworth PH, Hennessy DP, McCallum TH, Newmann EA (1994) The effects of modifying the amount of human contact on behavioral, physiological and production responses of laying hens. Applied Animal Behaviour Science 41:87-100.
Bertenshaw C, Rowlinson P (2009) Exploring stock managers' perceptions of the human-animal relationship on dairy farms and an association with milk production. Anthrozoos 22:59-69.
Bertin A, Mocz F, Calandreau L, Palme R, Lumineau S, Darmaillacq S, Houdelier C (2019) Human behavior at the origin of maternal effects on offspring behavior in laying hens (Gallus gallus domesticus). Physiology Behaviour 201:175-183.
Boissy A, Le Neindre P (1997) Behavioral, cardiac and cortisol responses to brief peer separation and reunion in cattle. Physiology Behavior 61:693-699.
Boissy A, Fisher A, Bouix J, Boivin X, Le Neindre P (2002, August) Genetics of fear and fearfulness in domestic herbivores. Paper presented at the Seventh World Congress on Genetics Applied to Livestock Production, Montpellier, FR.
Boivin S, Tournadre H, Le Neindre P (2000) Hand-feeding and gentling influence early weaned lambs´ attachment responses to their stock person. Journal of Animal Science 78:879-884.
Boivin X, Lensink BJ, Tallet C, Veissier I (2003) Stockmanship and farm animal welfare. Animal Welfare 12:479-92.
Bourguet C, Deiss V, Boissy A, Terlouw EMC (2015) Young Blond d'Aquitaine, Angus and Limousin bulls differ in emotional reactivity: Relationships with animal traits, stress reactions at slaughter and post-mortem muscle metabolism. Applied Animal Behaviour Science 164:41-55.
Brajon S, Laforest JP, Bergeron R, Tallet C, Hötzel MJ, Devillers N (2015) Persistency of the piglet's reactivity to the handler following a previous positive or negative experience. Applied Animal Behaviour Science 162:9-19.
Breuer K, Hemsworth PH, Barnett JL, Matthews LR, Coleman GL (2000) Behavioral response to humans and the productivity of commercial dairy cows. Applied Animal Behaviour Science 66:273-88.
Büttner K, Czycholl I, Basler H, Krieter J (2018) Effects of an intensified human-animal interaction on tail biting in pigs during the rearing period. Journal of Agricultural Science 156:1039-46.
Carbajal S, Orihuela A (2010) Minimal number of conspecifics needed to minimize the stress response of isolated mature ewes. Journal of Applied Animal Welfare Science 4:249-255.
Caroprese M, Napolitano F, Mattiello S, Fthenakis GC, Ribó O, Sevi A (2016) On-farm welfare monitoring of small ruminants. Small Ruminant Research 135:20-25.
Ceballos MC, Sant'Anna AC, Góis KCR, Ferraudo AS, Negrao JA, da Costa MJRP (2018) Investigating the relationship between human-animal interactions, reactivity, stress response and reproductive performance in Nellore heifers. Livestock Science 217:65-75.
Claxton AM (2011) The potential of the human–animal relationship as an environmental enrichment for the welfare of zoo-housed animals. Applied Animal Behaviour Science 133:1-10.
Cransberg PH, Hemsworth PH, Coleman GJ (2000) Human factors affecting the behavior and productivity of commercial broiler chickens. British Poultry Science 41:272-79.
de Oliveira D, Paranhos da Costa MJR, Zupan M, Rehn T, Keeling LJ (2015) Early human handling in non-weaned piglets: Effects on behavior and body weight. Applied Animal Behaviour Science 164:56-63.
de Passillé AM, Rushen J (2005) Can we measure human–animal interactions in on-farm animal welfare assessment? Some unresolved issues. Applied Animal Behaviour Science 92:193-209.
des Roches AB, Veisser I, Boivin X, Gilot-Fromont E, Mounier L (2016) A prospective exploration of farm, farmer, and animal characteristics in human-animal relationships: An epidemiological survey. Journal of Dairy Science 99:5573-85.
Destrez A, Haslin E, Boivin X (2018) What stockperson behavior during weighing reveals about the relationship between humans and suckling beef cattle: A preliminary study. Applied Animal Behavior Science 209:8-13.
Edwards LE, Botheras NA, Coleman GJ, Hemsworth PH (2010) Behavioral and physiological responses of laying hens to humans. Animal Production Science 50:557-59.
Ellingsen K, Coleman GJ, Lund V, Mejdell CM (2014) Using qualitative behavior assessment to explore the link between stockperson behavior and dairy calf behavior. Applied Animal Behavior Science 153:10-17.
Faure JM, Bessei W, Jones RB (2003) Direct selection for improvement of animal well-being. In: Muir WM, Aggrey SE (Eds.), Poultry Genetics, Breeding and Biotechnology (pp. 221-245). Wallingford, UK: CABI Publishing.
Ferguson DM, Warner RD (2008) Have we underestimated the impact of pre-slaughter stress on meat quality in ruminants? Meat Science 80:12-19.
Fukasawa M, Kawahata M, Higashiyama Y, Komatsu T (2017) Relationship between the stockperson's attitudes and dairy productivity in Japan. Animal Science Journal 88:394-400.
Gonyou HW, Hemsworth PH, Barnett JL (1986) Effects of frequent interactions with humans on growing pigs. Applied Animal Behaviour Science 16:269-78.
Graml C, Waiblinger S, Niebuhr K (2008a) Validation of tests for on-farm assessment of the hen-human relationship in non-cage systems. Applied Animal Behaviour Science 111:301-310.
Graml C, Niebuhr K, Waiblinger S (2008b) Reaction of laying hens to humans in the home or a novel environment. Applied Animal Behaviour Science 113:98-109.
Gross WB, Siegel PB (1982) Socialization as a factor in resistance to disease, feed efficiency and response to antigen in chickens. American Journal of Veterinary Research 43:2010-12.
Hausberger M, Roche H, Henry S, Visser EK (2008) A review of the human-horse relationship. Applied Animal Behaviour Science 109:1-24.
Hemsworth PH, Barnett JL, Hansen C (1981) The influence of handling by humans on the behavior, growth and corticosteroids in the juvenile female pig. Hormones and Behavior 15:396-403.
Hemsworth PH, Barnett JL, Hansen C, Gonyou HW (1986a) The influence of early contact with humans on subsequent behavioral response of pigs to humans. Applied Animal Behaviour Science 15:55-63.
Hemsworth PH, Gonyou HW, Dziuk PJ (1986b) Human communication with pigs: the behavioral response of pigs to specific human signals. Applied Animal Behaviour Science 15:45-54.
Hemsworth PH, Barnett JL, Hansen C (1986c) The influence of handling by humans on the behavior, reproduction and corticosteroids of male and female pigs. Applied Animal Behaviour Science 15:303-14.
Hemsworth PH, Barnett JL, Hansen C (1987) The influence of inconsistent handling by humans on the behavior, growth and corticosteroids of young pigs. Applied Animal Behaviour Science 17:245-52.
Hemsworth PH, Barnett JL, Coleman GJ, Hansen C (1989b) A study of the relationships between the attitudinal and behavioral profiles of stockpersons and the level of fear of human and reproductive performance of commercial pigs. Applied Animal Behaviour Science 23:301-14.
Hemsworth PH, Barnett JL, Tilbrook AJ, Hansen C (1989a) The effects of handling by humans at calving and during milking on the behavior and milk cortisol concentrations of primiparous dairy cows. Applied Animal Behaviour Science 22:313-26.
Hemsworth PH, Barnett JL, Treacy D, Madgwick P (1990) The heritability of the trait fear of humans and the association between this trait and subsequent reproductive performance of gilts. Applied Animal Behaviour Science 25:85-95.
Hemsworth PH, Barnett JL (1991) The effects of aversively handling pigs, either individually or in groups, on their behavior, growth and corticosteroids. Applied Animal Behaviour Science 30:61-72.
Hemsworth PH, Coleman GJ, Cox M, Barnett JL (1994) Stimulus generalization: the inability of piglets to discriminate between humans on the basis of their previous handling experience. Applied Animal Behaviour Science 40:129-42.
Hemsworth PH, Coleman GJ (1998) Human-Livestock Interactions: The Stockperson and the Productivity and Welfare of Intensively Farmed Animals. Wallingford, UK: CAB International.
Hemsworth PH, Coleman GJ, Barnett JL, Borg S (2000) Relationships between human-animal interactions and productivity of commercial dairy cows. Journal of Animal Science 78:2821-31.
Hemsworth PH (2003) Human-animal interactions in livestock production. Applied Animal Behaviour Science 81:185-98.
Hemsworth PH (2008) Human-pig relationships. In: Faucitano L, Schaefer AL (Eds.), Welfare of Pigs from Birth to Slaughter (pp. 271-288). Wageningen, NL: Academic Publishers.
Hemsworth PH (2009) Impact of human-animal interactions on the health, productivity and welfare of farm animals. In: Aland A, Madec F (Eds.), Sustainable Animal Production: The Challenges and Potential Developments for Professional Farming (pp. 57-68), Wageningen, NL: Academic Publishers.
Hemsworth PH, Barnett JL, Coleman GJ (2009) The integration of human-animal relations into animal welfare monitoring schemes. Animal Welfare 18:335-45.
Hemsworth PH, Coleman GJ (2011) Human-animal interactions and animal productivity and welfare. In: Human-livestock interactions. The Stockperson and the Productivity of Intensively Farmed Animals (pp. 47-83). Oxford, UK: CAB International.
Henry S, Richard-Yris MA, Hausberger M (2006) Influence of various early human-foal interferences on subsequent human-foal relationship. Developmental Psychobiology 48:712-718.
Ivemeyer S, Knierim U, Waiblinger S (2011) Effect of human-animal relationship and management on udder health in Swiss dairy herds. Journal of Dairy Science 94:5890-5902.
Ivemeyer S, Simantke C, Ebinghaus A, Poulsen PH, Sorensen JT, Rousing T, Knierim U (2018) Herd-level associations between human-animal relationship, management, fecal cortisol metabolites, and udder health of organic dairy cows. Journal of Dairy Science 101:7361-74.
Jago JG, Krohn CC, Matthews LR (1999) The influence of feeding and handling on the development of the human–animal interactions in young cattle. Applied Animal Behaviour Science 62:137-51.
Janczak AM, Pedersen LJ, Rydhmer L, Bakken M (2003) Relation between early fear- and anxiety-related behavior and maternal ability in sows. Applied Animal Behaviour Science 82:121-35.
Johansson A, Blokhuis HJ, Berckmans D, Butterworth A (2015) Development of an automatic method to assess the human-animal relationship in broilers at flock level. Paper presented at the Seventh European Conference on Precision Livestock Farming, Milan, ITL.
Jones RB, Waddington D (1993) Attenuation of the domestic chick´s fear of human beings via regular handling: in search of a sensitive period. Applied Animal Behaviour Science 36:185-195.
Jones RB, Hemsworth PH, Barnett JL (1993, September) Fear of humans and performance in commercial broiler flocks. In: Savory CJ, Hughes BO (Eds.), Proceedings of the 4th UFAW European Symposium on Poultry Welfare, Potters Bar, UK.
Jones RB (1996) Fear and adaptability in poultry: insights, implications and imperatives. World Poultry Science Journal 52:133-74.
Kasimanickam VR, Staker C, Williams HM, Kastelic JP, Kasimanickam R (2018) Aggressive attempted escape behavior during head-lock restraint reduced reproductive performances in Holstein heifers. Theriogenology 121:147-152.
Kling-Eveillard F, Hostiou N, Ganis E, Philibert A (2017, September) The effects of PLF on human-animal relationships on farms. Paper presented at the 8th European Conference on Precision Livestock Farming, Nantes, FR.
Lankin V (1997) Factors of diversity of domestic behavior in sheep. Genetics Selection Evolution 29:73-92.
Le Neindre P, Boivin X, Boissy A (1996) Handling of extensively kept animals. Applied Animal Behaviour Science 49:73–81.
Le Neindre P, Trillat C, Sapa J, Ménissier F, Bonnet JN, Chupin J (1995) Individual differences in docility in Limousin cattle. Journal of Animal Science 73:2249–2253.
Lensink BJ, Leruste H, Le Roux T, Bizeray-Filoche D (2009a) Relationship between the behavior of sows at 6 months old and the behavior and performance at farrowing. Animal 3:128-134.
Lensink BJ, Leruste H, de Bretagne T, Bizeray-Filoche D (2009b) Sow behavior towards humans during standard management procedures and their relationship to piglet survival. Applied Animal Behaviour Science 119:151-157.
Lürzel S, Münsch C, Windschnurer I, Futschik A, Palme R, Waiblinger S (2015) The influence of gentle interactions on avoidance distance towards humans, weight gain and physiological parameters in group-housed dairy calves. Applied Animal Behaviour Science 172:9-16.
Lyons DM, Price EO, Moberg GP (1988) Individual differences in temperament of domestic dairy goats: constancy and change. Animal Behaviour 36:1323-1333.
Macedo GG, Zúccari CE, de Abreu UG, Negrão JA, da Costa e Silva EV (2011) Human-animal interaction, stress, and embryo production in Bos indicus embryo donors under tropical conditions. Tropical Animal Health and Production 43:1175-1182.
Markowitz TM, Dally MR, Gursky K, Price EO (1998) Early handling increases lamb affinity for humans. Animal Behaviour 55:573-587.
Mattiello S, Klotz C, Baroli D, Minero M, Ferrente V, Canali E (2009) Welfare problems in alpine cattle farms in Alto Adige (Eastern Italian Alps). Italian Journal of Animal Science 8:628-30.
Mattiello S, Battini M, Andreoli E, Minero M, Barbieri S, Canali E (2010) Avoidance distance test in goats: A comparison with its application in cows. Small Ruminant Research 91:215-218.
Meagher RK, von Keyserlingk MAG, Atkinson D, Weary DM (2016) Inconsistency in dairy calves’ responses to tests of fearfulness. Applied Animal Behaviour Science 185:15-22.
Munksgaard L, de Passillé AM, Rushen J, Thodberg K, Jensen MB (1997) Discrimination of people by dairy cows based on handling. Journal of Dairy Science 80:1106-1112.
Muns R, Rault JL, Hemsworth P (2015) Positive human contact on the first day of life alters the piglet's behavioral response to humans and husbandry practices. Physiology Behavior 151:162-167.
Napolitano F, De Rosa G, Girolami A, Scavone M, Braghieri A (2011) Avoidance distance in sheep: Test–retest reliability and relationship with stockmen attitude. Small Ruminant Research 99:81-86.
Napolitano F, Pacelli C, Grasso F, Braghieri A, De Rosa G (2013) The behavior and welfare of buffaloes (Bubalus bubalis) in modern dairy enterprises. Animal 7:1704-1713.
Napolitano F, Serrapica M, Braghieri A, Masucci F, Sabia E, De Rosa G (2019) Human-animal interactions in dairy buffalo farms. Animals 9:246.
Pajor EA, Rushen J, de Passillé AMB (2000). Aversion learning techniques to evaluate dairy cattle handling practices. Applied Animal Behaviour Science 69:89-102.
Powell C, Hemsworth LM, Rice M, Hemsworth PH (2016) Comparison of methods to assess fear of humans in commercial breeding gilts and sows. Applied Animal Behaviour Science 181:70-75.
Prado VM, Orihuela A, Lozano TS, Pérez-León MI (2001) Effect of the breeding system (extensive vs. semi-intensive) of male goat, on obtaining semen via artificial vagina. Veterinaria México 32:297-299.
Price EO, Orihuela A (2010) Conducta Animal Aplicada al Cuidado y Producción Pecuaria. (Animal Behavior Applied to Livestock Care and Production). México, D.F.: Editorial Trillas.
Probst JK, Neff AS, Leiber F, Kreuzer M, Hillmann E (2012) Gentle touching in early life reduces avoidance distance and slaughter stress in beef cattle. Applied Animal Behaviour Science 139:42-49.
Probst JK, Hillmann E, Leiber F, Kreuzer M, Spengler NA (2013) Influence of gentle touching applied few weeks before slaughter on avoidance distance and slaughter stress in finishing cattle. Applied Animal Behaviour Science 144:14-21.
Prunier A, Tallet C (2015) Chapter 12. Endocrine and behavioural responses of sows to human interactions and consequences on reproductive performance. In: Farmer C (Ed.), The Gestating and Lactating Sow (279-296). Wageningen, NL: Academic Publishers.
Raubek J, Niebuhr K, Waiblinger S (2007) Development of on-farm methods to assess the animal-human relationship in laying hens kept in non-cage systems. Animal Welfare 16:173-175.
Rochais C, Henry S, Sankey C, Nassur F, Goracka-Bruzda A, Hausberger M (2014) Visual attention, an indicator of human-animal relationships? A study of domestic horses (Equus caballus). Frontiers in Psychology 5:108.
Rueda PM, Sant'Anna AC, Valente TS, da Costa MJRP (2015) Impact of the temperament of Nellore cows on the quality of handling and pregnancy rates in fixed-time artificial insemination. Livestock Science 177:189-95.
Rushen J, Taylor AA, de Passillé AM (1999a). Domestic animals’ fear of humans and its effect on their welfare. Applied Animal Behaviour Science 65:285-303.
Rushen J, de Passillé AM, Munksgaard L (1999b) Fear of people by cows and effects on milk yield, behaviour and heart rate at milking. Journal of Dairy Science 82:720-27.
Rushen J, de Passillé AM (2015) The importance of good stockmanship and its benefits to animals. In: Grandin T (Ed.), Improving Animal Welfare: A Practical Approach (pp. 125-138), Wallingford, UK: CAB International.
Sankey C, Richard-Yris MA, Leroy H, Henry S, Hausberger M (2010) Positive interactions lead to lasting positive memories in horses, Equus caballus. Animal Behavior 79:869-875.
Schmied C, Boivin X, Scala S, Waiblinger S (2010) Effect of previous stroking on reactions to a veterinary procedure behavior and heart rate of dairy cows. Interaction Studies 11:467-81.
Scott K, Laws DM, Courboulay V, Meunier-Salaün MC, Edwards SA (2009) Comparison of methods to assess fear of humans in sows. Applied Animal Behaviour Science 118:36-41.
Seabrook, M. F. (1984). The psychological interaction between the stockman and his animals and its influence on performance of pigs and dairy cows. Veterinary Science, 115, 84–87.
Sommavilla R, Hötzel MJ, Dalla Costa OA (2011) Piglets’ weaning behavioral response is influenced by quality of human-animal interactions during suckling. Animal 5:1426-1431.
Spoolder H (2007) Fear of humans. In: Velarde A, Geers R (Eds.), On Farm Monitoring of Pig Welfare (pp. 33-39), Wageningen, NL: Academic Publications.
Tallet C, Veissier I, Boivin X (2005) Human contact and feeding as rewards for the lamb's affinity to their stockperson. Applied Animal Behaviour Science 94:59-73.
Tallet C, Veissier I, Boivin X (2008) Temporal association between food distribution and human caregiver presence and the development of affinity to humans in lambs. Developmental Psychobiology 50:147-159.
Tallet C, Brilloüet A, Meunier-Salaün MC, Paulmier V, Guérin C, Prunier A (2013) Effects of neonatal castration on social behavior, human-animal relationship and feeding activity in finishing pigs reared in a conventional or an enriched housing. Applied Animal Behaviour Science 145:70-83.
Tallet C, Brajon S, Devillers N, Lensink J (2018) Pig-human interactions: Creating a positive perception of humans to ensure pig welfare. In: Špinka M (Ed.). Advances in Pig Welfare, (pp. 381-398). Amsterdam, NL: Elsevier Science.
Tanida H, Miura A, Tanaka T, Yoshimoto T (1995) Behavioral response to humans in individually handled weaning pigs. Applied Animal Behaviour Science 42:249-59.
Tosi MV, Hemsworth PH (2002) Stockperson-husbandry interactions and animal welfare in the extensive livestock industries. Paper presented at the 36th International Society for Applied Ethology Congress, Wageningen NL.
Waiblinger S, Menke C, Coleman G (2002) The relationship between attitudes, personal characteristics and behavior of stockpeople and subsequent behavior and production of dairy cows. Applied Animal Behaviour Science 79:195-219.
Waiblinger S, Menke C, Korff J, Bucher A (2004) Previous handling and gentle interactions affect behavior and heart rate of dairy cows during a veterinary procedure. Applied Animal Behaviour Science 85, 31–42.
Waiblinger S, Boivin X, Pedersen V, Tosi MV, Janczak AM, Visser EK, Jones RB (2006) Assessing the human-animal relationship in farmed species: a critical review. Applied Animal Behaviour Science 101:185-242.
Waiblinger S (2017) Human-animal relations. In: P. Jensen (Ed.), The Ethology of Domestic Animals: An Introductory Text, (pp. 135-146). Wallingford UK: CAB International,
Waiblinger S (2019) Agricultural animals. In: Hosey G and Melfi V (Eds.), Anthrozoology: Human-Animal Interactions in Domesticated and Wild Animals, (pp. 32-58). Oxford, UK: Oxford University Press.
Waynert DF, Stookey JM, Schwartzkopf-Genswein KS, Watts JM, Waltz CS (1999) The response of beef cattle to noise during handling. Applied Animal Behaviour Science 62:27-42.
Welfare Quality® (2009a) Assessment Protocol for Cattle. Welfare Quality® Consortium, Lelystad, The Netherlands.
Welfare Quality® (2009b) Assessment Protocol for Pigs. Welfare Quality® Consortium, Lelystad, The Netherlands.
Welfare Quality® (2009c) Assessment Protocol for Poultry. Welfare Quality® Consortium, Lelystad, The Netherlands.
Welp T, Rushen J, Kramer DL, Festa-Bianchet M, de Passillé AM (2004) Vigilance as a measure of fear in dairy cattle. Applied Animal Behaviour Science 87:1-13.
Windschnurer I, Schmied C, Boivin X, Waiblinger S (2008) Reliability and inter-test relationship of tests for on-farm assessment of dairy cows' relationship to humans. Applied Animal Behaviour Science 114:37-53.
Windschnurer I, Boivin X, Waiblinger S (2009) Reliability of an avoidance distance test for the assessment of animals’ responsiveness to humans and a preliminary investigation of its association with farmers’ attitudes on bull fattening farms. Applied Animal Behaviour Science 117:117-127.
Zulkifli I, Gilbert J, Liew PK, Ginsos J (2002) The effects of regular visual contact with human beings on fear, stress, antibody and growth responses in broiler chickens. Applied Animal Behaviour Science 79:103-112.
Zulkifli I, Siti Nor Azah A (2004) Fear and stress reactions, and the performance of commercial broiler chickens subjected to regular pleasant and unpleasant contacts with human being. Applied Animal Behaviour Science 88:77-87.
Zulkifli I (2013) Review of human-animal interactions and their impact on animal productivity and welfare. Journal of Animal Science and Biotechnology 4:25.