Influences of Maternal Care on Chicken Welfare

Abstract

Simple SummaryFor a domestic chick, the mother hen is an important role model; chicks learn a great deal from their mother about what to peck, when to rest and how to behave when there is a threat. However, in large farms, natural brooding is not commercially viable and so chicks are hatched in large incubators and reared artificially. Chicks reared without a mother in this way are more fearful and more likely to develop behavioural problems, such as feather pecking. We discuss the important features of maternal care in chickens, the behavioural consequences of deprivation, and the welfare implications on commercial farms. We finish by suggesting ways to simulate natural maternal care to improve commercial chick rearing practice.AbstractIn domestic chickens, the provision of maternal care strongly influences the behavioural development of chicks. Mother hens play an important role in directing their chicks’ behaviour and are able to buffer their chicks’ response to stressors. Chicks imprint upon their mother, who is key in directing the chicks’ behaviour and in allowing them to develop food preferences. Chicks reared by a mother hen are less fearful and show higher levels of behavioural synchronisation than chicks reared artificially. In a commercial setting, more fearful chicks with unsynchronised behaviour are more likely to develop behavioural problems, such as feather pecking. As well as being an inherent welfare problem, fear can also lead to panic responses, smothering, and fractured bones. Despite the beneficial effects of brooding, it is not commercially viable to allow natural brooding on farms and so chicks are hatched in large incubators and reared artificially, without a mother hen. In this review we cover the literature demonstrating the important features of maternal care in domestic chickens, the behavioural consequences of deprivation and the welfare implications on commercial farms. We finish by suggesting ways to use research in natural maternal care to improve commercial chick rearing practice.

Modulation of Fear and Arousal Behavior by Serotonin Transporter (5-HTT) Genotypes in Newly Hatched Chickens

“…This resembles findings from several animal studies including mice, rats and chickens, which estimated fear and arousal responses to acute and chronic stresses or to social isolation (Goldsmith et al, 1978 ; Roth and Katz, 1979 ; Katz et al, 1981 ; Heiblum et al, 1998 ). For young chickens, the vicinity to the social group might provide shelter from e.g., predation and in a natural context at the age of 5 weeks the peer group is also usually linked to maternal presence (Edgar et al, 2013 , 2016 ). Thus, a high level of locomotor activity here reflects likely a high arousal and fear level as these chicks invest more, in terms of locomotion, into trying to return to the peer group.…”

A review of environmental enrichment for laying hens during rearing in relation to their behavioral and physiological development

“…In contrast, domestic chicks in commercial production systems are never in contact with their mother (for logistical and health reasons). This may have negative implications for the development of appropriate fear responses where chicks could either have increased fear to non-threatening stimuli or inappropriate reactions to potential threats (Campo et al., 2014; Edgar et al., 2016). Some positive effects of the mother hen can be simulated with dark brooders which are warm, enclosed, dark areas for chicks to access in the absence of adult hens (Gilani et al., 2012; Riber and Guzman, 2016, 2017).…”

Bushmeat trade consequences predict higher anxiety, restraint, and dominance in chimpanzees

“…Experimental studies have shown that early life stress has enduring effects at behavioral and physiology levels in several animal species. Chickens ( Gallus gallus ) artificially reared are more likely to develop behavioral problems than mother‐reared individuals (Edgar, Held, Jones, & Troisi, ). In rodents, unpredictability of maternally derived sensory signals provoke emotional and cognitive dysfunction in offspring (Baram et al, ), and globally neglect‐like environments in rat pups lead to long‐term depression‐like behavioral traits and to altered physiological and hormonal activity, and gut microbiota composition (Murthy & Gould, ; O'Mahony et al, ; Pryce, Rüedi‐Bettschen, Dettling, & Feldon, ).…”