The influence of dietary supplementation with oyster mushroom waste on laying hens' performance, egg quality and immune parameters.

The objective of the present study was to evaluate the effects of dietary supplementation with oyster mushroom (Pleurotus ostreatus) waste (OMW) on performance, egg quality, fatty acid (FA) profile and oxidative stability, serum and yolk cholesterol and immune parameters of laying hens. Two hundred fifty-six laying hens were allocated into 4 treatment groups, with eight replicate cages, and were fed for 28 d either a control diet, or diets supplemented with OMW at 1, 2 or 4 g per 100 g feed (P1, P2 and P4 experimental groups, respectively). No significant effects were detected on the performance and egg quality (P > 0.

Genetic differentiation of mainland-island sheep of Greece: Implications for identifying candidate genes for long-term local adaptation.

In Greece, a number of local sheep breeds are raised in a wide range of ecological niches across the country. These breeds can be used for the identification of genetic variants that contribute to local adaptation. To this end, 50k genotypes of 90 local sheep from mainland Greece (Epirus, n = 35 and Peloponnesus, n = 55) were used, as well as 147 genotypes of sheep from insular Greece (Skyros, n = 21), Lemnos, n = 36 and Lesvos, n = 90).

Allele and genotype frequencies of the gene polymorphism associated with canine degenerative myelopathy in Belgian Malinois dogs in Greece.

Background And Aim: Canine degenerative myelopathy (CDM) is an adult-onset fatal disorder associated with a point mutation of the superoxide dismutase 1 () gene (). This study aimed to determine the allele and genotype frequencies of this mutation in a group of Belgian Malinois dogs in Greece.

Materials And Methods: Samples (n=72) of whole blood were collected from 72 purebred dogs of the Hellenic Armed Forces; these samples were processed for DNA isolation, polymerase chain reaction, and digestion with the restriction endonuclease .

Detection of loci exhibiting pleiotropic effects on body weight and egg number in female broilers.

The objective of the present study was to discover the genetic variants, functional candidate genes, biological processes and molecular functions underlying the negative genetic correlation observed between body weight (BW) and egg number (EN) traits in female broilers. To this end, first a bivariate genome-wide association and second stepwise conditional-joint analyses were performed using 2586 female broilers and 240 k autosomal SNPs. The aforementioned analyses resulted in a total number of 49 independent cross-phenotype (CP) significant SNPs with 35 independent markers showing antagonistic action i.

Hesperidin and Naringin Improve Broiler Meat Fatty Acid Profile and Modulate the Expression of Genes Involved in Fatty Acid β-oxidation and Antioxidant Defense in a Dose Dependent Manner.

The beneficial properties of the flavanones hesperidin and naringin as feed additives in poultry have lately been under investigation. In broilers, both flavanones have been shown to exhibit antioxidant properties while their individual effects on fatty acid (FA) composition and the underlying molecular mechanisms of their activity have not been explored. Here, we studied their effects on broiler meats' FA profiles and on the expression of genes related to lipid metabolism, antioxidant defense and anti-inflammatory function.

Clustering patterns mirror the geographical distribution and genetic history of Lemnos and Lesvos sheep populations.

Elucidating the genetic variation and structure of Lemnos and Lesvos sheep is critical for maintaining local genetic diversity, ecosystem integrity and resilience of local food production of the two North Aegean islands. In the present study, we explored genetic diversity and differentiation as well as population structure of the Lemnos and Lesvos sheep. Furthermore, we sought to identify a small panel of markers with the highest discriminatory power to assign animals across islands.

Deciphering the mode of action and position of genetic variants impacting on egg number in broiler breeders.

Background: Aim of the present study was first to identify genetic variants associated with egg number (EN) in female broilers, second to describe the mode of their gene action (additive and/or dominant) and third to provide a list with implicated candidate genes for the trait. A number of 2586 female broilers genotyped with the high density (~ 600 k) SNP array and with records on EN (mean = 132.4 eggs, SD = 29.

Discovery and characterization of functional modules associated with body weight in broilers.

Aim of the present study was to investigate whether body weight (BW) in broilers is associated with functional modular genes. To this end, first a GWAS for BW was conducted using 6,598 broilers and the high density SNP array. The next step was to search for positional candidate genes and QTLs within strong LD genomic regions around the significant SNPs.

Combined GWAS and 'guilt by association'-based prioritization analysis identifies functional candidate genes for body size in sheep.

Background: Body size in sheep is an important indicator of productivity, growth and health as well as of environmental adaptation. It is a composite quantitative trait that has been studied with high-throughput genomic methods, i.e.

Effects of egg storage on hatchability, chick quality, performance and immunocompetence parameters of broiler chickens.

Pre-incubation egg storage is a necessity for the poultry industry. This study evaluated the effects of pre-incubation storage length of broiler eggs on hatchability, 1-day-old chick quality, subsequent performance, and immunocompetence. To this end, a total of 360 hatching eggs were stored for 4, 12, or 16 d prior to incubation.

Direct BMP2/4 signaling through BMP receptor IA regulates fetal thymocyte progenitor homeostasis and differentiation to CD4+CD8+ double-positive cell.

BMP2/4 signaling is required for embryogenesis and involved in thymus morphogenesis and T-lineage differentiation. In vitro experiments have shown that treatment of thymus explants with exogenous BMP4 negatively regulated differentiation of early thymocyte progenitors and the transition from CD4-CD8- (DN) to CD4+CD8+ (DP). Here we show that in vivo BMP2/4 signaling is required for fetal thymocyte progenitor homeostasis and expansion, but negatively regulates differentiation from DN to DP cell.

Non-redundant role for the transcription factor Gli1 at multiple stages of thymocyte development.

The Hedgehog (Hh) signaling pathway influences multiple stages of murine T-cell development. Hh signaling mediates transcriptional changes by the activity of the Gli family of transcription factors, Gli1, Gli2 and Gli3. Both Gli2 and Gli3 are essential for mouse development and can be processed to function as transcriptional repressors or transcriptional activators, whereas Gli1, itself a transcriptional target of Hh pathway activation, can only function as a transcriptional activator and is not essential for mouse development.

The Gli3 transcription factor expressed in the thymus stroma controls thymocyte negative selection via Hedgehog-dependent and -independent mechanisms.

The Hedgehog (Hh) responsive transcription factor Gli3 is required for efficient thymocyte development in the fetus. In this study we show that Gli3, not detected in adult thymocytes, is expressed in the murine fetal and adult thymus stroma. PCR array analysis revealed Cxcl9, Rbp1, and Nos2 as novel target genes of Gli3.

Sonic hedgehog negatively regulates pre-TCR-induced differentiation by a Gli2-dependent mechanism.

Hedgehog signaling regulates differentiation, survival, and proliferation of the earliest double-negative (DN) thymocytes, but its importance at later stages of T-cell development is controversial. Here we use loss- and gain-of-function mouse models to show that Shh, by signaling directly to the developing thymocyte, is a negative regulator of pre-TCR-induced differentiation from DN to double-positive (DP) cell. When hedgehog signaling was reduced, in the Shh(-/-) and Gli2(-/-) thymus, or by T lineage-specific transgenic expression of a transcriptional-repressor form of Gli2 (Gli2DeltaC(2)), differentiation to DP cell after pre-TCR signal transduction was increased.

Indian hedgehog (Ihh) both promotes and restricts thymocyte differentiation.

We show that Indian Hedgehog (Ihh) regulates T-cell development and homeostasis in both fetal and adult thymus, controlling thymocyte number. Fetal Ihh(-/-) thymi had reduced differentiation to double-positive (DP) cell and reduced cell numbers compared with wild-type littermates. Surprisingly, fetal Ihh(+/-) thymi had increased thymocyte numbers and proportion of DP cells relative to wild type, indicating that Ihh also negatively regulates thymocyte development.

KLF13 influences multiple stages of both B and T cell development.

The Kruppel-like factor, KLF13, is a member of a family of transcription factors shown to be involved in haematopoietic development. Here we show that KLF13 is involved in the development of B and T cells at multiple stages. Expression of KLF13 in the thymus was maximal in the DP population and in KLF13(-/-) deficient mice there was an accumulation of DP thymocytes and reduction of CD4(+)SP cells.

Repression of hedgehog signal transduction in T-lineage cells increases TCR-induced activation and proliferation.

Hedgehog proteins signal for differentiation, survival and proliferation of the earliest thymocyte progenitors, but their functions at later stages of thymocyte development and in peripheral T-cell function are controversial. Here we show that repression of Hedgehog (Hh) pathway activation in T-lineage cells, by expression of a transgenic repressor form of Gli2 (Gli2DeltaC2), increased T-cell differentiation and activation in response to TCR signalling. Expression of the Gli2DeltaC2 transgene increased differentiation from CD4(+)CD8(+) to single positive thymocyte, and increased peripheral T cell populations.

Splenomegaly and modified erythropoiesis in KLF13-/- mice.

To study the function of the Krüppel-like transcription factor KLF13 in vivo, we generated mice with a disrupted Klf13 allele. Although Klf13(-/-) mice are viable, fewer mice were present at 3 weeks than predicted by Mendelian inheritance. Viable Klf13(-/-) mice had reduced numbers of circulating erythrocytes and a larger spleen.

A novel role for Hedgehog in T-cell receptor signaling: implications for development and immunity.

The Hedgehog (Hh) signaling pathway is a key regulator of both embryonic development and homeostasis of adult tissues, including thymus and blood. In the thymus, Hh signals for differentiation, survival and proliferation in the early stages of T cell development, before TCR gene rearrangement. Our recent data has shown that Hh signaling also modulates T cell receptor (TCR) signal strength in more mature T lineage cells.

Sonic hedgehog signalling in T-cell development and activation.

The production of mature functional T cells in the thymus requires signals from the thymic epithelium. Here, we review recent experiments showing that one way in which the epithelium controls the production of mature T cells is by the secretion of sonic hedgehog (SHH). We consider the increasing evidence that SHH-induced signalling is not only important for the differentiation and proliferation of early thymocyte progenitors, but also for modulating T-cell receptor signalling during repertoire selection, with implications for positive selection, CD4 versus CD8 lineage commitment, and clonal deletion of autoreactive cells.

Beta-selection: abundance of TCRbeta-/gammadelta- CD44- CD25- (DN4) cells in the foetal thymus.

Expression of TCRbeta and pre-TCR signalling are essential for differentiation of CD4- CD8- double negative (DN) thymocytes to the CD4+ CD8+ double-positive (DP) stage. Thymocyte development in adult Rag1, Rag2 or TCRbetadelta-deficient mice is arrested at the DN3 stage leading to the assumption that pre-TCR signalling and beta-selection occur at, and are obligatory for, the transition from DN3 to DN4. We show that the majority of DN3 and DN4 cells that differentiate during early embryogenesis in wild-type mice do not express intracellular (ic) TCRbeta/gammadelta.

Activation of the Hedgehog signaling pathway in T-lineage cells inhibits TCR repertoire selection in the thymus and peripheral T-cell activation.

TCR signal strength is involved in many cell fate decisions in the T-cell lineage. Here, we show that transcriptional events induced by Hedgehog (Hh) signaling reduced TCR signal strength in mice. Activation of Hh signaling in thymocytes in vivo by expression of a transgenic transcriptional-activator form of Gli2 (Gli2DeltaN(2)) changed the outcome of TCR ligation at many stages of thymocyte development, allowing self-reactive cells to escape clonal deletion; reducing transgenic TCR-mediated positive selection; reducing the ratio of CD4/CD8 single-positive (SP) cells; and reducing cell surface CD5 expression.

The transcription factor Gli3 regulates differentiation of fetal CD4- CD8- double-negative thymocytes.

Glioblastoma 3 (Gli3) is a transcription factor involved in patterning and oncogenesis. Here, we demonstrate a role for Gli3 in thymocyte development. Gli3 is differentially expressed in fetal CD4- CD8- double-negative (DN) thymocytes and is most highly expressed at the CD44+ CD25- DN (DN1) and CD44- CD25- (DN4) stages of development but was not detected in adult thymocytes.

Reduced thymocyte development in sonic hedgehog knockout embryos.

The Hedgehog family of secreted intercellular signaling molecules are regulators of patterning and organogenesis during animal development. In this study we provide genetic evidence that Sonic Hedgehog (Shh) has a role in the control of murine T cell development. Analysis of Shh(-/-) mouse embryos revealed that Shh regulates fetal thymus cellularity and thymocyte differentiation.

The role of morphogens in T-cell development.

The Hedgehog (Hh) and Wnt family proteins, and the bone morphogenetic proteins (BMPs) 2 and 4, act as morphogens during vertebrate embryogenesis and organogenesis by regulating patterning and cell fate. They have recently been found to have a role in regulating cell fate and determination in self-renewing tissues in adults, such as the immune system and haematopoietic system. This Review presents studies on the role of Sonic Hh (Shh), Wnts and BMP2/4 in the regulation of thymocyte development.