Background: The Tibial dyschondroplasia (TD) in fast-growing chickens is mainly caused by improper blood circulation. The exact mechanism underlying angiogenesis and vascularization in tibial growth plate of broiler chickens remains unclear. Therefore, this research attempts to study genes involved in the regulation of angiogenesis in chicken red blood cells. Twenty-four broiler chickens were allotted into a control and thiram (Tetramethyl thiuram disulfide) group. Blood samples were collected on day 2, 6 (8- and 14-days old chickens) and 15 (23 days old chickens).Results: Histopathology and hematoxylin and eosin (H&E) results showed that angiogenesis decreased on the 6th day of the experiment but started to recover on the 15th day of the experiment. Immunohistochemistry (IHC) results confirmed the expressions of integrin alpha-v precursor (ITGAV) and clusterin precursor (CLU). Transcriptome sequencing analysis evaluated 293 differentially expressed genes (DEGs), of which 103 up-regulated genes and 190 down-regulated genes were enriched in the pathways of neuroactive ligand receptor interaction, mitogen-activated protein kinase (MAPK), ribosome, regulation of actin cytoskeleton, focal adhesion, natural killer cell mediated cytotoxicity and the notch signalling pathways. DEGs (n = 20) related to angiogenesis of chicken erythrocytes in the enriched pathways were thromboxane A2 receptor (TBXA2R),interleukin-1 receptor type 1 precursor (IL1R1),ribosomal protein L17 (RPL17),integrin beta-3 precursor (ITGB3), ITGAV,integrin beta-2 precursor (ITGB2),ras-related C3 botulinum toxin substrate 2 (RAC2),integrin alpha-2 (ITGA2),IQ motif containing GTPase activating protein 2 (IQGAP2),ARF GTPase-activating protein (GIT1),proto-oncogene vav (VAV1),integrin alpha-IIb-like (ITGA5),ras-related protein Rap-1b precursor (RAP1B),tyrosine protein kinase Fyn-like (FYN),tyrosine-protein phosphatase non-receptor type 11 (PTPN11),protein patched homolog 1 (PTCH1),nuclear receptor corepressor 2 (NCOR2) and mastermind like protein 3 (MAML3) selected for further confirmation with qPCR. However, commonly DEGs were sarcoplasmic/endoplasmic reticulum calcium ATPase 3 (ATP2A3), ubiquitin-conjugating enzyme E2 R2 (UBE2R2), centriole cilia and spindle-associated protein (CCSAP), coagulation factor XIII A chain protein (F13A1), shroom 2 isoform X6 (SHROOM2), ras GTPase-activating protein 3 (RASA3) andCLU.Conclusion: We have found potential therapeutic genes concerned to erythrocytes and blood regulation, which regulated the angiogenesis in thiram induced TD chickens. This study also revealed the potential functions of erythrocytes.Graphical 1. Tibial dyschondroplasia (TD) in chickens were more on day 6, which started recovering on day 15. 2. The enriched pathway observed in TD chickens on day 6 was ribosome pathway, on day 15 were regulation of actin cytoskeleton and focal adhesion pathway. 3. The genes involved in the ribosome pathways was ribosomal protein L17 (RPL17). regulation of actin cytoskeleton pathway were Ras-related C3 botulinum toxin substrate 2 (RAC2), Ras-related protein Rap-1b precursor (RAP1B), ARF GTPase-activating protein (GIT1), IQ motif containing GTPase activating protein 2 (IQGAP2), Integrin alpha-v precursor (ITGAV), Integrin alpha-2 (ITGA2), Integrin beta-2 precursor (ITGB2), Integrin beta-3 precursor (ITGB3), Integrin alpha-IIb-like (ITGA5). Focal adhesion Proto-oncogene vav (Vav-like), Tyrosine-protein kinase Fyn-like (FYN).

The histomorphology in quail, it is yet not to be done fully. Therefore, the present research has been carried out to understand the histomorphological architecture of the lymphoid organs (thymus, spleen, bursa of fabricius and intestinal villus) in Japanese quail. Initially 24 quail chicks were weighed and randomly divided into three age groups, i.e., a (2 weeks), b (4 weeks) and c (6 weeks). Histological study was performed on 3 μm thick transverse section, cut by microtome then fixed on slide and stained with haematoxylin and eosin, counter stain then tissue sections were examined on a Nikon phase contrast microscope the results of the gross morphology showed weight, length and width of lymphoid organs in all three age groups were insignificantly (p>0.05) higher in females than males, whereas, they were significantly (p0.05) higher in females than males. However, they were significantly (p<0.05) higher in group c, b and a respectively. Thymus shows immature fine fibrous connective tissue capsule, septa were invaded by lobules into cortex and medulla, and spleen was encapsulated by thin fibroblastic contained numerous smooth muscle cells & elastic fibers in their elliptical capsule. It can be concluded that the size of the thymus, bursa of fabricius and spleen reached its maximum at 5 to 6 week of age in male and 6 to 7 in female. Regression of thymic lobules, splenic nodules and bursal follicles were noticed with a clear change in shape with advancement of age from 2 to 6 week of age with an increased number of hassall’s corpuscles and adipocytes, whereas, height and width of intestinal villi were significantly higher from 2 to 6 week followed by thymic lobules, splenic pulp, and bursal follicle.