Effects of heat stress on peripheral T and B lymphocyte profiles and IgG and IgM serum levels in broiler chickens vaccinated for Newcastle disease virus.

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. This study aimed to discuss the effects of early-age heat stress on the blood lymphocyte phenotypes (B and T lymphocytes) and plasma immunoglobulin levels (IgM and IgG) in chickens vaccinated against paramixovirus of the Newcastle (NC) disease (LaSota strain). For this purpose, 96 male chickens (Cobb) were divided into 4 groups: 1) control (C), 2) heat-stressed (HS), 3) control vaccinated (C/V), and 4) heat-stressed and Vaccinated (HS/V). The NC vaccine was administered twice on experimental day (ED) 7 and ED14, and the heat stress (38 ± 1°C) was applied from ED2 to ED6. The data showed that HS increased the corticosterone serum levels in the HS group compared with the control groups (C and C/V groups). At ED7, increased concentrations of IgM were observed in birds in the HS and HS/V groups compared with C and C/V animals; chickens from the HS/V group presented increased IgG levels compared with those in the birds of the C group. The heat stress shifted the immune cell profile from B-lymphocyte to a T-cytotoxic and T-helper lymphocyte profile, and this immune cell pattern persisted until the end of the study period. It was concluded that heat stress immunomodulated the immune function response of the chickens to the NC disease vaccine challenge.

Methylenedioxymethamphetamine (Ecstasy) decreases neutrophil activity and alters leukocyte distribution in bone marrow, spleen and blood.

OBJECTIVE: Looking for possible neuroimmune relationships, we analyzed the effects of methylenedioxymethamphetamine (MDMA) administration on neuroendocrine, neutrophil activity and leukocyte distribution in mice. METHODS: Five experiments were performed. In the first, mice were treated with MDMA (10 mg/kg) 30, 60 min and 24 h prior to blood sample collection for neutrophil activity analysis. In the second experiment, the blood of naïve mice was collected and incubated with MDMA for neutrophil activity in vitro analysis. In the third and fourth experiments, mice were injected with MDMA (10 mg/kg) and 60 min later, blood and brain were collected to analyze corticosterone serum levels and hypothalamic noradrenaline (NA) levels and turnover. In the last experiment, mice were injected with MDMA 10 mg/kg and 60 min later, blood, bone marrow and spleen were collected for leukocyte distribution analysis. RESULTS: Results showed an increase in hypothalamic NA turnover and corticosterone serum levels 60 min after MDMA (10 mg/kg) administration, a decrease in peripheral blood neutrophil oxidative burst and a decrease in the percentage and intensity of neutrophil phagocytosis. It was further found that MDMA (10 mg/kg) treatment also altered leukocyte distribution in blood, bone marrow and spleen. In addition, no effects were observed for MDMA after in vitro exposure both in neutrophil oxidative burst and phagocytosis. CONCLUSION: The effects of MDMA administration (10 mg/kg) on neutrophil activity and leukocyte distribution might have been induced indirectly through noradrenergic neurons and/or hypothalamic-pituitary-adrenal axis activations.