Transport-related stress and its resolution in turkey pullets: activation of a pro-inflammatory response in peripheral blood leukocytes

Abstract

The transportation process is one of the most stressful practices in poultry and livestock management. Extensive knowledge is available on the impact of transport on stress and animal welfare; however, little is known on the impact of transport on the physiology of turkey pullets, their welfare and health, and even less on the process of homeostatic recovery in the post-transport new environment. The main focus of this manuscript was to focus on trauma, stress, and recovery following transport of turkey pullets from nurseries to pullet farms. Specifically, we determined the physiological consequences of transport, the temporal restoration of homeostasis and its effects on immune system function. We hypothesized that stress signaling by stress hormones would directly activate circulating turkey blood leukocytes (TBL), thus inducing a pro-inflammatory response directed towards tissue repair and recovery. Extensive blood analyses prior to transit and during the collecting, transit, and post-transit stages revealed extensive stress (elevated heat shock protein 70) and blunt-force trauma (internal bleeding and muscle damage as well as limb fractures). TBL were shown to increase mRNA expression of cortisol and adrenergic receptors during transit, thus indicating a possible direct response to circulating stress hormones. Consequently, TBL were shown to increase mRNA expression of pro-inflammatory cytokines, as well as that of serum inflammatory proteins (lysozyme and transferrin) partaking in reducing oxygen radicals as demonstrated by consumption of these proteins. The flare-up due to transit related stress diminished with time until 10 d post-transit, a time at which most parameters returned to resting levels. Though general and vaccine-specific antibody levels were not altered by transport-related stress, the physical and physiological injury caused during transport may explain the susceptibility of turkey pullets to opportunist pathogens in the immediate post-transit period.

Increased serum levels of advanced glycation end products due to induced molting in hen layers trigger a proinflammatory response by peripheral blood leukocytes

“…Our previous studies and those of others indicated an interaction between oxidative stress and the proinflammatory response ( Lee et al., 2019 , Wein et al., 2017a , Wein et al., 2017b ). Thus, restoration of homeostasis in broilers and turkeys in a state of oxidative stress (induced by transport) involved activation of an innate immune response.…”

“…Previously published observations by our group and others showed that stress induces upregulation of serum acute phase proteins, including lysozyme and transferrin and suggested that these acute phase proteins act as a means to restore homeostasis ( Cray et al., 2009 , Kim et al., 2011 , Yildiz and Altunay, 2011 , Najafi et al., 2016 , Wein et al., 2017a , Wein et al., 2017b ). Induced molting led to increased levels and mRNA of lysozyme and transferrin and thus support the previous observations.…”

“…SIRT1 has also been shown to be an effector protein, having both cytosolic and nuclear activity ( Hipkiss, 2008 , Hayashida et al., 2010 , Cantó and Auwerx, 2012 ). Upregulation of SIRT1 enhances the affinity of HSF-1 to the HSP70 gene promotor, a product indicative of stress ( Wein et al., 2017a , Wein et al., 2017b ) and prolongs their binding duration ( Johnson and Fleshner, 2006 ). Thus, the increase of both SIRT1 and HSP70 mRNA during IM indicates that the metabolic energy shift induced a stress response in hen PBL.…”

“…Thus, restoration of homeostasis in broilers and turkeys in a state of oxidative stress (induced by transport) involved activation of an innate immune response. Increased expression of proinflammatory immune-response genes (i.e., interleukin [ IL]-6 and IL-1β) in peripheral blood leukocytes ( PBL ) as well as elevation of acute phase antioxidative proteins (i.e., lysozyme and transferrin) in serum ( Wein et al., 2017a , Wein et al., 2017b ). Owing to these observations and studies supporting an interaction between oxidative stress and a proinflammatory response ( Li et al., 1995 , Cadenas and Davies, 2000 , Finkel and Holbrook, 2000 , Nyska and Kohen, 2002 , Gallo et al., 2014 ), our aims were to confirm oxidative stress due to IM in layers and to investigate whether oxidative stress is involved the activation of a proinflammatory response.…”

Presence of Virulence Genes inEnterococcusSpecies Isolated from Meat Turkeys in Germany Does Not Correlate with Chicken Embryo Lethality

“…e isolates from the present study originated from turkey poults with yolk sacculitis (n � 15) and from the internal organs of subadult birds (n � 13). Commercially raised poults experience different stressors during the first week of life and might be more prone to enterococcal infections compared to subadult birds [70]. Consequently, one would expect that Enterococcus infections in subadult turkeys are caused by virulent strains and by predominant species in poultry disease such as E. faecalis.…”