Vet Immunol Immunopathol
April 2019
Information on the dynamics of the chicken immune system during bacterial or parasite challenge in the presence or absence of stressful situations may provide a better understanding of the complex mechanisms behind these diseases. Necrotic enteritis (NE) had been controlled previously by the proper use of antimicrobial agents; however, more recently, NE has reemerged in many countries. The imposed restrictions on antimicrobial use and/or the intensive productive programs implemented by producers are challenges the birds, leading to large host adaptive responses that in many instances are like those elicited by stressors.
View Article and Find Full Text PDFRes Vet Sci
April 2019
Heat stress has a relevant effect on animal health and productivity. Stress and environmental changes can contribute to disease development, such as avian necrotic enteritis (NE). The goal of this study was to analyze the effects of heat stress applied to broiler chickens in an experimental model of co-infection with Clostridium perfringens and Eimeria spp.
View Article and Find Full Text PDFHeat stress has been related to the impairment of behavioral and immunological parameters in broiler chickens. However, the literature is not clear on the involvement of neuroimmune interactions in a heat stress situation associated with bacterial and parasitic infections. The present study evaluated the production of monoamines and their metabolites in brain regions (rostral pallium, hypothalamus, brain stem, and midbrain) in broiler chickens submitted to chronic heat stress and/or infection and co-infection with spp.
View Article and Find Full Text PDFCohabitation with Ehrlich ascitic tumor-injected conspecifics induces behavioral, neurochemical, endocrine and immune changes indicative of stress and immune impairment in female mice. The present work analyzed the effects of similar cohabitation in Swiss and Balb/C male mice. At least 12 pairs of male mice were divided into a control group and an experimental group.
View Article and Find Full Text PDFVet Immunol Immunopathol
March 2016
Avian necrotic enteritis (NE) induced by Clostridium perfringens is a disease that affects mainly the first weeks of poultry's life. The pathogenesis of NE is complex and involves the combination of several factors, such as co-infection with different species of coccidia, immunosuppression and stress. Stress is one of the main limiting factors in poultry production.
View Article and Find Full Text PDFThe gut-brain axis is known to modulate behavioral and immune responses in animals; evidence supporting this modulation in chickens, however, is elusive. Here, we analyzed the effects of heat stress and/orClostridium perfringens (CP) infection on behavior, intestinal morphology, brain activity, and corticosterone serum levels in chickens. Broilers were randomly divided into 5 equal groups: a naïve group (N), a thioglycolate group (T), a thioglycolate heat-stressed group (T/HS35), an infected group (I), and an infected/stressed (I/HS35) group.
View Article and Find Full Text PDFWe analysed the effects of cold stress (19 ± 1°C, 6 h /day, from the first to the seventh day of life) applied to specific pathogen free (SPF) chickens. On experimental Day 1 (ED1), chicks were divided into four groups: C (not infected and kept under thermoneutral condition); CS (not infected and cold stressed); PC (Salmonella Heidelberg (SH) infected and kept under thermoneutral condition) and PCS (SH infected and cold stressed). High concentrations of corticosterone were found in the cold stressed birds on ED7 and ED21, with a greater increase in birds of the PCS group.
View Article and Find Full Text PDFPoult Sci
October 2015
Multiple factors, such as environment, nutritional status, and disease, induce stress in animals during livestock production. It has been shown that poultry exposed to stressors for prolonged periods had decreases in their performance parameters, mortality and decreased host resistance to pathogenic agents. It seems that early age stress may have long-lasting impact and could possibly modify the expression of their genetic potential on growth performance and immunity.
View Article and Find Full Text PDFStressful conditions are predisposing factors for disease development. Heat stress is one of the most important stressors in poultry production. The reemergence of some previously controlled diseases [e.
View Article and Find Full Text PDFCampylobacter jejuni is a pathogen of the gastrointestinal tract of humans, but colonizes chickens for prolonged periods without causing disease. It is unclear what host and bacterial mechanisms maintain a non-inflammatory state in chickens. The present work was undertaken to characterize cytokine responses of chickens to purified lipooligosaccharide (LOS) of C.
View Article and Find Full Text PDFEur J Pharmacol
March 2012
Acute lung injury is an inflammatory condition for which treatment is mainly supportive because effective therapies have not been developed. Cannabidiol, a non-psychotropic cannabinoid component of marijuana (Cannabis sativa), has potent immunosuppressive and anti-inflammatory properties. Therefore, we investigated the possible anti-inflammatory effect of cannabidiol in a murine model of acute lung injury.
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