Toll like receptor 4 signaling pathway participated in Salmonella lipopolysaccharide-induced spleen injury in young chicks.

Spleen is one of the crucial sites for cellular and humoral immunity but it easily damaged during pathogenic infections resulting in immunosuppression. The current study was therefore performed to explore the mechanism of acute spleen injury induced by salmonella lipopolysaccharide (LPS) in young chicks. Healthy one-day-old Cobb strain broiler chicks were intra-peritoneally injected with saline or LPS. LPS treatment caused significant decreases in body and spleen weights at 36 and 72 h. Histological analysis showed the changes of ellipsoid structures with beginning of nuclear pyknosis and karyolysis similar to steatosis at 12 h, maximum histopathological lesions were seen at 36 h, however these were disappeared at 72 h post LPS stimulation. Cell proliferation was decreased (low PCNA positivity) and apoptosis increased (high ssDNA positivity) in the spleen at 12 and 36 h after LPS treatment. The expression levels of mRNA for caspase-3, caspase-8, B-cell lymphoma 2 (BCL-2), tumor protein p53 or p53 and Bcl-2 homologous antagonist killer (BAK) showed slight increase at some time points following LPS stimulation. LPS treatment also induced significant up-regulation in toll like receptor 4 (TLR4) at 36 h post LPS stimulation and slight increase in expressions of its downstream molecules (MyD88 and NF-κB) at 12 h post LPS treatment. The keystone cytokines (TNF-α and IL-6) exhibited significant up-regulation at 12 h following LPS stimulation. Our findings provided novel information about the histopathological as well as apoptotic and proliferative alterations in spleen mediated by TLR4 signaling induced by Salmonella LPS in avian species.

Genetic and phenotypic characterization of the native rabbits in Middle Egypt.

AIM: Native rabbits in smallholder system are considered as important genetic resources, and the present study was aimed to study the genetic and phenotypic characterization and detection of the maternal origin of the native rabbit populations located at the Middle of Egypt. MATERIALS AND METHODS: A survey of native rabbit populations was conducted in three governorates (Fayum [FY], Beni Suef [BN], and El Menia [MN]). The phenotypic characterization of rabbits included the profile body of the head, ears, eyes, neck, and legs and the coat colors. The blood samples were collected for genetic characterization based on mitochondrial (cytochrome b) and the microsatellite markers. RESULTS: The phenotypic characterization of the body parts in the three populations was almost similar. The body weight of the mature rabbits in MN Government was significantly heaviest, and the measurements for the main body parts (body length, chest circumference, and abdominal girth) were the highest compared to the two populations. The results of mitochondrial (cytochrome b) analysis revealed that the rabbits from the three governments belonged to lineage A except one animal was recorded as lineage G from MN's rabbit population. The results of the microsatellite markers revealed that the genetic diversity between the three populations showed genetic interferences; however, a closer genetic relationship was observed between BN and MN than FY. The majority of the genetic diversity was the individual variability. CONCLUSION: The mitochondrial lineage A is the major lineage in rabbit populations in the area of the Middle Egypt understudy. The genetic populations' structure is the interferences among the three populations. A large-scale survey should be done on native rabbit populations for the sustainable management and conservation of the local breeds' genetic resources.