Objective: The aim of this work was to investigate three different mutations; Fec-B, FecX^G, Fec-G^H at three candidate genes; Bone morphogenetic protein receptor IB, Bone morphogenetic protein 15 and Growth Differentiation Factor 9, respectively, in six sheep breeds reared in Egypt namely; Rahmani, Barki, Rahmani X Barki cross, Awassi, Awassi X Suffolk cross, and Ossimi and their association with litter size. Results: Genomic DNA of 132 sheep was investigated for the Fec-B, FecX^G, and Fec-G^H mutations by Restriction Fragment Length Polymorphism, Single-Stranded Conformation Polymorphism and DNA sequencing. The results revealed that all breeds did not carry Fec-B mutation. On the other side, the mutations of FecX^G, and Fec-G^H were detected in Rahmani, and Rahmani X Barki cross which is associated with the high twinning rate/litter size of Rahmani (1.28) and Rahmani X Barki cross (1.22). While, the average litter size for other breeds had almost a constant values rate over six parities, ranging between 1.00 and 1.04.

Nile tilapia (Oreochromis niloticus) and European sea bass (Dicentrarchus labrax) are economically significant species in Mediterranean countries, serving essential roles in the aquaculture industry due to high market demand and nutritional value. They experience substantial losses from bacterial pathogens Vibrio anguillarum and Streptococcus iniae, particularly at the onset of the summer season. The immune mechanisms involved in fish infections by V. anguillarum and S. iniae remain poorly understood. This study investigated their impact through experiments with control and V. anguillarum- and S. iniae-infected groups for each species. Blood samples were collected at 1, 3, and 7 days post bacterial injection to assess biochemical and immunological parameters, including enzyme activities (AST and ALT), oxidative markers (SOD, GPX, CAT, and MDA), and leukocyte counts. Further analyses included phagocyte activity, lysozyme activity, IgM levels, and complement C3 and C4 levels. Muscle tissues were sampled at 1, 3, and 7 days post injection to assess mRNA expression levels of 18 immune-relevant genes. The focus was on cytokines and immune-related genes, including pro-inflammatory cytokines (TNF-α, TNF-β, IL-2, IL-6, IL-8, IL-12, and IFN-γ), major histocompatibility complex components (MHC-IIα and MHC-IIβ), cytokine receptors (CXCL-10 and CD4-L2), antimicrobial peptides (Pleurocidin and β-defensin), immune regulatory peptides (Thymosin β12, Leap 2, and Lysozyme g), and Galectins (Galectin-8 and Galectin-9). β-actin was used as the housekeeping gene for normalization. Significant species-specific responses were observed in N. Tilapia and E. Sea Bass when infected with V. anguillarum and S. iniae, highlighting differences in biochemical, immune, and gene expression profiles. Notably, in N. Tilapia, AST levels significantly increased by day 7 during S. iniae infection, reaching 45.00 ± 3.00 (p < 0.05), indicating late-stage acute stress or tissue damage. Conversely, E. Sea Bass exhibited a significant rise in ALT levels by day 7 in the S. iniae group, peaking at 33.5 ± 3.20 (p < 0.05), suggesting liver distress or a systemic inflammatory response. On the immunological front, N. Tilapia showed significant increases in respiratory burst activity on day 1 for both pathogens, with values of 0.28 ± 0.03 for V. anguillarum and 0.25 ± 0.02 for S. iniae (p < 0.05), indicating robust initial immune activation. Finally, the gene expression analysis revealed a pronounced peak of TNF-α in E. Sea Bass by day 7 post V. anguillarum infection with a fold change of 6.120, suggesting a strong species-specific pro-inflammatory response strategy. Understanding these responses provides critical insights for enhancing disease management and productivity in aquaculture operations.

Distinctive molecular approaches and tools, particularly high-throughput SNP genotyping, have been applied to determine and discover SNPs, potential genes of interest, indicators of evolutionary selection, genetic abnormalities, molecular indicators, and loci associated with quantitative traits (QTLs) in various livestock species. These methods have also been used to obtain whole-genome sequencing (WGS) data, enabling the implementation of genomic selection. Genomic selection allows for selection decisions based on genomic-estimated breeding values (GEBV). The estimation of GEBV relies on the calculation of SNP effects using prediction equations derived from a subset of individuals in the reference population who possess both SNP genotypes and phenotypes for target traits. Compared to traditional methods, modern genomic selection methods offer advantages for sex-limited traits, low heritability traits, late-measured traits, and the potential to increase genetic gain by reducing generation intervals. The current availability of high-density genotyping and next-generation sequencing data allow for genome-wide scans for selection. This investigation provides an overview of the essential role of advanced molecular tools in studying genetic diversity and implementing genomic selection. It also highlights the significance of adaptive selection in light of new high-throughput genomic technologies and the establishment of selective comparisons between different genomes. Moreover, this investigation presents candidate genes and QTLs associated with various traits in different livestock species, such as body conformation, meat production and quality, carcass characteristics and composition, milk yield and composition, fertility, fiber production and characteristics, and disease resistance.

The aim of this study was to determine the properties and quality characteristics of hair and cashmere fibres of three goat breeds raised in Southwest China, namely; Dazu black goat (DBG, n = 203; ♂99, ♀104), Inner Mongolia cashmere goat (IMCG, n = 65; 21♂, 44♀) and their first cross (F₁, n = 79; 39♂, 40♀). Totals of 5219, 2130 and 2981 fibre samples, from the three breeds respectively, were taken prior to shearing at 32.5 ± 01.25 months of age from four body sites; shoulder, side-portion, abdomen and leg. Breed effect was significant (P < 0.01) for most hair and cashmere properties. IMCG and F₁ hair lengths were longer (P < 0.001) with less variable lengths than DBG. Shoulder hair diameters of the three breeds were not different (P > 0.05) but biggest of the side-portion and abdomen sites of DBG were bigger (P > 0.01), however, the biggest (P < 0.001) hair diameter was recorded for the leg site of F₁ and the smallest (P > 0.01) for IMCG. IMCG recorded the longest value for cashmere lengths followed by DBG, while F₁ recorded the lowest (P = 0.001), whilst F₁ recorded the biggest (P = 0.001) diameter whereas no differences existed between parents' breeds. The cortical cell lengths of IMCG and DBG were 94.57 and 86.85 μm without significant difference detected between breeds. Differences between hair length and diameter for body sites of the studied goat breeds were significant (P < 0.01) but between whiteness, cashmere diameter and diameter of cortical cells were not. Sex had no significant effect on all hair/cashmere properties. Quality characteristics of cashmere fibres from IMCG and F₁ were better (P < 0.001) than from DBG. Leg hair diameter, curl recovery rate and cashmere diameter were superior in the crossbred F₁ compared to pure breed parents, and DBG was superior to IMCG for fibre elasticity and intensity traits. FGF-5 gene was detected as a candidate gene for hair and cashmere traits in IMCG breed. Whilst, KIT gene was found to be associated with coat colour in the studied breeds. Extra investigations to examine more cashmere goat breeds and crosses are needed to discover genetic variability in cashmere production locally and worldwide.