The advancement of genetic engineering in chickens has enabled significant advancement in developmental biology, bioreactors, and disease resilience. The development of CRISPR/Cas9 genome engineering technology has further expanded the potential applications of genetic engineering in poultry. In this study we aimed to evaluate the efficacy of a direct transfection method, previously demonstrated to produce transgenic chickens, in generating gene knockout (KO) chickens. Specifically, we targeted the Interferon-α/β Receptor 1 (IFNAR1) and Interleukin 1 receptor, type I (IL1R1), both critical pathways in the inflammatory and antiviral responses. We designed guide RNAs targeting the genes and validated their efficiency vivo via microinjection into the developing embryos. PCR analysis confirmed the presence of gene deletions in chimeric roosters, which were subsequently bred to produce G1 germline heterozygote KO offspring. Homozygous KO chickens were generated and subjected to phenotypic and functional analyses. Our results demonstrated successful generation of functional knockouts of both IFNAR1 and IL1R1 using a direct transfection. Overall, this study demonstrates that direct transfection provides a robust and predictable method for generating KO chickens, facilitating further research into avian immune responses and the development of antiviral strategies.

It is essential to identify potential genes and genetic variants associated with growth traits to enhance sheep breeding. Previous studies have suggested that the Rho GTPase-activating protein 24 () gene may influence the growth of some animals. However, no association has been established between polymorphisms in the gene and sheep growth traits. In this study, single-nucleotide polymorphisms (SNPs) in the gene of Hu sheep were detected, and functional SNPs associated with Hu sheep growth traits were identified. Twenty-six SNPs were discovered in Hu sheep. Association analysis revealed NC_056059.1:g.455981A > G was significantly associated with average daily gain from six months to one year of age, while NC_056059.1:g.456083 A > G was significantly associated with average daily gain from weaning to six months of age. The relative fluorescence activity (firefly luciferase and sea kidney luciferase) of haplotype GGGG was significantly lower than that of haplotypes GGAA, AAAA and AAGG. Furthermore, mRNA expression in the longissimus dorsi muscle of six-months-old sheep was significantly lower than birth sheep. The results showed that NC_056059.1:g.455981A > G and g NC_056059.1:g.456083A > G of gene were related to some growth traits of Hu sheep, and mRNA was differentially expressed in longissimus dorsi muscle of Hu sheep at different months of age, which could be used as a candidate gene for molecular marker-assisted selection of Hu sheep.

Sheep breeding has been a fundamental aspect of livestock farming for thousands of years, supplying humans with wool, meat, and milk. As the livestock sector adapts to contemporary needs, the increasing global demand for animal products, fueled by population growth, highlights the significance of effective breeding techniques. Growth and meat traits are a key factor in sheep breeding, directly impacting resource efficiency and breeder profitability. In this review, we have explored the advantages of molecular marker-assisted selection (MAS) and its specific applications in breeding meat sheep. We summarized research on quantitative trait loci (QTLs) and genome-wide association studies (GWAS), as well as variations in key genes, including myostatin (), insulin-like growth factor 1 (), and calpastatin (), associated with growth, meat quality, and carcass traits in sheep. The advancements in molecular breeding for meat sheep, along with improvements in sheep genetics, genomic selection, and genome editing, have enhanced our understanding of DNA markers and demonstrated the genetic diversity present in meat sheep, significantly enriching sheep breeding strategies. Improvements in sample size, phenotyping efficiency, and the integration of omics studies could enhance our understanding of gene interactions, enabling MAS technology to reach its full potential.

Egg weight is a primary economic trait in poultry breeding. Putian Black duck, an excellent local laying duck breed in Fujian Province, includes two different strains, black feather strain and white feather strain. The white feather strain of Putian Black duck is also known as Putian White duck. Except for the different feather colors, these two strains differ in egg weight. In this study, whole-genome resequencing was conducted on Putian Black duck and Putian White duck to explore the differences in the genetic mechanism of egg weight. and were identified as key candidate genes affecting egg weight. Mass spectrometry was used to detect the SNPs of and . Result indicates that the SNPs of and in both populations exhibited moderate polymorphism, and Putian Black duck possessed higher genetic variation and potential selectivity. Association analysis indicated that in Putian Black duck, four SNPs in the gene were significantly associated with egg weight. These loci can be used as molecular markers for improving egg weight in Putian Black duck.

Genomics offers a promising solution by enabling precise cattle selection and breeding to boost productivity and sustainability. In Peru, livestock plays a crucial role in the economy and food security. Despite its importance, the sector faces significant challenges, including poor pasture quality, limited conservation practices, a shortage of trained professionals, minimal use of genomic tools, and an incomplete understanding of the genetic potential of both native and introduced breeds. Since the 1940s, Peru has advanced in genetic improvement through artificial insemination, improved semen preservation, the establishment of a National Semen Bank, and the introduction of new breeds. Key developments have included embryo transfer, in vitro fertilization, and pioneering cloning efforts. Future perspectives for livestock genomics in Peru involve expanding bioinformatics capacity, improving genomic infrastructure, and integrating genomic selection into national breeding strategies. This review discusses the history, current status, challenges, and future perspectives of livestock genomics in Peru.

The efficacy of microbial fermented feeds (FF) is highly dependent on microbial composition, underscoring the need for locally sourced, cost-effective formulations to advance sustainable livestock production. In this study, bacteria from corn silage (CSB) were screened for the preparation of solid-state fermented feed (SFF). In addition, for the purpose of comparison, purchased marketed fermentation bacteria (PMB) for SFF were also tested using the same methodology. Anaerobic fermentation was carried out by adding 5% CSB, PMB, and saline to conventional feeds at 37 °C, respectively. Then 10 g of fermentation samples was collected on days 0, 3, and 5, respectively. The composition and diversity of the microbial community were subsequently analyzed using high-throughput sequencing. The pH, titratable acidity (TA), and nutrient index of the feeds before and after fermentation were determined. High-throughput sequencing results showed that the dominant genera of CSB were , , and , whereas the dominant genera of PMB were , , , and . The dominant genera in unfermented feeds (CK) were , , and . In addition, the dominant genera in SFF supplemented with CSB and PMB were and , respectively. Compared with CK, pH of SFF supplemented with CSB and PMB decreased gradually, and TA increased significantly and then decreased gradually during fermentation. Similarly, Crude fiber content was higher than CK in both CSB and PMB, while crude fat content was lower than CK for all of them. The study illustrates that CSB can be used to ferment porcine solid feeds and that CSB solid feed microorganisms may promote intestinal absorption of complex polysaccharides in pigs, which lays a certain theoretical foundation for the application of CSB to SFF.

The gastrointestinal microbiome is pivotal to nutrient utilization and productivity in dairy cattle. This study compared the ruminal and fecal microbiomes of Holstein, Jersey, and Jeju Black cattle using 16S rRNA gene sequencing and three taxonomic classification databases to identify microbial differences across breeds. A total of 25 samples were analysed to evaluate microbial composition, diversity, functional phenotypes, and interactions. Jeju Black cattle exhibited significantly higher ruminal diversity ( < 0.001), whereas Holstein and Jersey cows had more diverse fecal microbiomes. , and dominated the rumen of commercial breeds, while and were enriched in Jeju Black cattle. Amino acid prototrophs were abundant in Holstein and Jersey feces, while sulfur-metabolizing microbial phenotypes predominated in the Jeju Black rumen, with implications for nitrogen metabolism and methane production. Microbial network analysis revealed as a high-centrality genus in Holstein and Jersey cows, and in Jersey cows, potentially linked to propionate production. Jeju Black cattle displayed distinct microbial interactions involving sulphur-reducing and methanogenic bacteria. These results might be showing breed-related microbiome variability, potentially influencing feed efficiency, fermentation, and emissions. However, future work should standardize diets, feeding conditions, sampling methods, and include performance metrics to clarify breed-specificity of microbiome-function relationships.

The growth of livestock is influenced by both genetic and environmental factors, with genes like Non-SMC Condensin I complex subunit G () playing key roles in regulating growth. Previous studies have suggested that is associated with growth traits in species such as cattle, sheep, and chickens. In this study, we comprehensively assessed polymorphisms and their association with body weight (BW), chest circumference (CC), body height (BH), and body length (BL) at six stages (from newborn to 30 months) in 469 Nanjiang Yellow goats, utilizing the Generalized Linear Mixed Models (GLMM). Pearson correlation analysis revealed the strongest correlation between BW and CC (R = 0.91), followed by BW and BL (R = 0.87), and BW and BH (R = 0.89). Additionally, 24 single nucleotide polymorphisms (SNPs) within the NCAPG gene were identified, which were relatively conserved across closely related species. A notable missense mutation (g.5705 A > G) in exon 6 resulted in an amino acid substitution (281 Ile > Met), which may alter the physicochemical properties and conformation of the NCAPG protein. The resulting impairment in condensin function delays chromosome segregation, prolongs metaphase in growth plate stem cells, and enhances proliferative signaling, ultimately leading to variations in body size. Correlation analysis revealed that 13 of these SNPs were concurrently associated with multiple growth traits, including BH, BL, and CC. These polymorphisms in the gene represent potential candidates for marker-assisted selection (MAS) to improve body size in Nanjiang Yellow goats.

This study explored the effects of dietary supplementation with a probiotic blend of subsp. and on the performance and health of growing rabbits. Ninety-six rabbits were allocated into three groups and fed for eight weeks on diets containing either no probiotic (control), a low-dose probiotic (1 ml/kg of each probiotic strain), or a high-dose probiotic (2 ml/kg of each probiotic strain). Probiotic inclusion, particularly at the higher level, significantly enhanced final body weight, feed conversion ratio, and overall performance. Improvements were also noted in carcass characteristics, with greater yields in both forequarters and hindquarters. Blood biochemical analysis revealed elevated antioxidant enzyme activity and immunoglobulin levels, alongside reductions in lipid fractions and better liver and kidney function indicators. Meat quality also benefited, as shown by lower pH, reduced water holding capacity and cooking loss, and more favorable color metrics. Microbial analysis of cecal and feed samples indicated a notable increase in beneficial bacteria and a decline in pathogenic species in the probiotic-treated groups. These findings suggest that combined probiotic supplementation is a promising strategy for enhancing growth performance, meat quality, and gut health in rabbit production systems to produce a good final meat product.

Mastitis, an inflammation of the bovine mammary gland, reduces dairy productivity and poses significant health risks to Ethiopian dairy cattle. This study aimed to identify genomic regions associated with milk somatic cell score (SCS) and estimate its genetic parameters. The dataset included 1647 phenotypic cows, 6964 genotyped animals, and 39,976 single nucleotide polymorphism (SNP) markers. A single-step genome-wide association study (ssGWAS) was conducted, accounting for fixed effects of parity, genomic breed composition, altitude, and lactation stage, and random effects of herd-year-calving-season and permanent environment. Genetic variance using 20 adjacent SNPs sliding windows explaining ≥1% of the total genetic variance were used for candidate genes and quantitative trait loci (QTL) identifications. The estimated heritability of SCS was 0.11 ± 0.06. Genomic regions on BTA 15, 19, and 26 were identified associated with SCS, encompassing 116 genes, including MPP7, MPP8, MMP13, BIRC2, BIRC3, BTRC, SRSF1, and MPO, which are involved in immunity, inflammation, apoptosis, antimicrobial defense, and tissue remodeling. Gene enrichment analysis revealed that the genes are involved collagen catabolic process and IL-17 signaling pathway. These findings provide insights into genomic regions that could be targeted in genomic selection to improve mastitis resistance in Ethiopian dairy cattle.

Kalmyk cattle are an important meat breed in Kazakhstan, valued for their strong physique, genetic stability, and adaptability. In this study, we investigated the mRNA expression of ELOVL fatty acid elongase 6 () and CREB-regulated transcription coactivator 2 () across multiple tissues, and further examined their genetic variations and associations with growth and carcass traits in 200 Kalmyk cattle. Expression analysis showed that was most highly expressed in the heart and liver, whereas was predominantly expressed in the spleen and large intestine, highlighting their tissue-specific expression patterns. In addition, we identified a polymorphic SNP (g.16511290A > G) in the 3'UTR of , with three genotypes (AA, AG, GG) and the G allele being dominant (0.520). Polymorphism information content (PIC) analysis indicated high genetic diversity at this locus. Importantly, this SNP was significantly associated with live weight and body oblique length ( < 0.05), and individuals carrying heterozygous AG genotype showed higher body weight and length. Collectively, these findings suggest that g.16511290A > G within may serve as useful molecular markers for body measurements and meat traits, providing valuable resources for marker-assisted selection in beef cattle breeding programs.

Eucommia ulmoides (EU) is a traditional medicinal plant widely cultivated across China. The combination of EU and feed significantly affects the growth performance, intestinal microbiota composition, and metabolic characteristics of weaned piglets. Forty Landrace x Yorkshire piglets were randomly assigned to four groups: a control group receiving a basal diet, three treatment groups receiving a basal diet supplemented with EU and EU with mix energy (EU+ME), and EU with high protein and energy (EU+HPE), respectively. Growth performance was monitored over a 25-day feeding period, and fecal samples were collected for subsequent metagenomic sequencing and metabolomic analysis. Piglets supplemented with EU, EU+ME, and EU+HPE exhibited significantly improved growth performance, compared to the control group. Metagenomic analysis revealed significant alterations in gut microbiota composition, with increased beneficial bacterial classes and suppression of Prevotella spp. Metabolomic profiling demonstrated distinct metabolic alterations among the treatment groups, with pathway impact analysis highlighting enhanced protein synthesis and energy metabolism. Furthermore, EU supplementation did not affect porcine epidemic diarrhea virus activity in vitro but reduced LPS-induced intestinal inflammation. These findings suggest that EU could be a promising natural additive for improving piglet health and growth, with potential implications for managing post-weaning challenges in swine production.

Fistulated animals and rumen simulation systems are essential for evaluating the effects of ingredients like probiotics, proposed as sustainable alternatives to growth-promoting antibiotics in ruminant nutrition. This study assessed the impact of microencapsulated probiotics on the structure and functionality of an initial ruminal microbial community using (IVV) and (IVT) systems. The IVT system was inoculated with rumen fluid obtained from the cattle animal used as IVV system. Over time, both systems were analysed for short-chain fatty acid (SCFA) production, microbial composition and functionality using next-generation sequencing. Physicochemical parameters were consistent across both systems and the inoculum, with an increase in propionate concentration observed. Although the microbial composition of IVV and IVT systems was highly similar (Pearson correlation of 0.869), significant differences in B-diversity were noted ( value = 0.023). The systems also exhibited high similarity in enzymatic profiles (correlation: 0.971) and metabolic pathways (correlation: 0.938), despite differences in functional B-diversity. Both systems showed increased production of fibrolytic enzymes, enhancing feed efficiency. The use of microencapsulated probiotics induced both taxonomic and functional changes in the initial microbial community of the IVT and IVV systems, which can be linked to the zootechnical effects of using probiotics as additives in ruminal animal nutrition.

The Cinghiato pig population originates from a breeding project aimed at reconstituting an extinct local swine breed, historically depicted in frescoes in Umbria, Central Italy. The selection strategy employed a reconstruction breeding program, choosing mating pairs based on the unique coat phenotype represented in these artworks. Unlike the traditional Cinta Senese breed, Cinghiato pigs exhibit a white belt encircling the trunk, while their forelimbs remain black. This study explores the genetic background of the belted coat pattern observed in the heterogeneous reconstituted population. Twenty-two pigs were genotyped using the Porcine GGP 80K SNP BeadChip. Genetic analyses were conducted to assess population structure and diversity, with comparisons made to other Italian pig breeds and wild boars. Findings reveal moderate genetic diversity within the Cinghiato population. Runs of Homozygosity patterns suggest historical inbreeding events. Moreover, several genomic regions were associated with traits relevant to niche pork production, including feed intake, leg conformation, and fat deposition. Polymorphisms were detected in 10 coat color-related genes (, and ). Although some candidate variants were identified, this preliminary study highlights the need for further research to clarify the genetic mechanisms underlying the phenotypic variability of belted coat patterns.

This article strove to characterize and compare biochemical, oxidative, bacteriological and immunological semen properties in Zemplin, Liptov Baldspotted and New Zealand rabbits. Besides, bacteria were characterized using the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Oxidative profile of semen was assessed using chemiluminescent and colorimetric protocols. Levels of pro-inflammatory cytokines were evaluated with the enzyme-linked immunosorbent assay. Seminal plasma biochemistry was assessed with an automated clinical chemistry analyser. The lowest sperm concentration and motility were found in the Liptov Baldspotted ejaculates which also presented with significantly ( < 0.01) elevated levels of tumour necrosis factor alpha (TNF-α) and interleukin 1, free radicals ( < 0.0001) and malondialdehyde ( < 0.0001) in comparison to New Zealand rabbits. The prevailing bacterial genera in semen were spp., spp., spp. and spp. Significantly increased levels of alanine transaminase and creatinine (Crea) were found in New Zealand rabbits in comparison to the Liptov Baldspotted breed ( < 0.001). Overall, Liptov Baldspotted rabbits produced semen of lower quality than Zemplin and New Zealand rabbits, suggesting that this breed may be more predisposed to a higher susceptibility to internal and external stresses which may interfere with male fertility.

Buffaloes are mono-ovulating animals, with only about 5% of primordial follicles being fully capable of maturation into primary oocytes throughout their reproductive years. primordial follicle activation technology provides a new way to manipulate and utilize oocyte resources. However, activation of buffalo primordial follicles has not been reported. In this study, buffalo cortical strips were cultured and activated with PI3K and mTOR stimulators, and the proportion of activated and developed follicles was evaluated and compared between groups . Furthermore, the key genes involved in primordial follicle activation were screened using RNA sequencing. Results showed that buffalo ovarian cortex can be well preserved by being cultured for at least 7 days and maintain its tissue properties and follicular morphology. , treatment with PI3K and mTOR pathway stimulators significantly enhanced the activation efficiency of the primordial follicles. In addition,  several differentially expressed genes related to follicular development, such as IDO1, CXCL10 and CXCL6 were significantly up-regulated after stimulation. Our findings demonstrate that PI3K and mTOR stimulators can significantly promote the activation and development of buffalo follicles, and providing technical support and a theoretical basis for the optimization of culture technology of buffalo preantral follicles .

The objective of this study was to perform genome-wide association analysis and thus search for candidate genes for milk production and composition, milk coagulation properties (MCP), and milk protein profile in dairy sheep from a New Zealand flock. After quality control, 45,801 single nucleotide polymorphisms (SNPs) were included in the analysis, 147 ewes, and 470 individual records. A total of 87 SNPs and 55 candidate genes were found across autosomes (OAR) 2, 3, 6, 16, 18, 20, 25, and 26. Of particular importance, were the candidate genes PDZRN4 for milk yield, and BMP2K for contents of α- and α-caseins. No SNPs were found in the casein genes, LALBA or PAEP. Only one SNP was significant for MCP, and overall, the genetic architecture of MCP was similar to that of ratio of casein to calcium, pH, lactose, and the ratio of casein to protein. Further studies with larger flocks and with genomic imputation are required to validate the findings of this study before incorporating markers or genes into breeding programmes.

Healthy Qinchuan bulls aged 8.5-9.5 years were selected and randomly divided into 6 groups based on 0%, 2%, 4%, 6%, 8%, and 10% dietary supplementation of peony seed meal for three months. Overall, linear motility (LM), progressive motility (PM), straight-line velocity (VSL), curvilinear velocity (VCL), and the percentage increase of all sperm grades (A to D) were affected (p<0.05) by the dietary supplementation. LM (29.5 vs. 24.1%), PM (69.4 vs. 60.0%), VLS (38.0 vs. 33.3 μm/s), and VCL (48.3 vs. 44.3 μm/s) were consistently higher in the 6% peony seed meal dietary supplementation groups than in the control group, respectively. A similar pattern was observed in the 8% group. Inversely to sperm grades C and D, grades A and B were higher in all treated groups than the control group, except for the 2% group in sperm grade A. Moreover, the levels of the enzymes Superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR; except for 2% peony seed group), and glutathione peroxidase (GSH-px) were higher than the control group. The level of malondialdehyde (MDA) was lower in all treated groups than in the control group. Dietary supplementation of 2-8% peony seed meal improves the semen quality of aged Qinchuan bulls.

This study was designed to assess the genetic diversity and population genetic structure of five sheep breeds in Shanxi Province, China, and to infer the heterosis potential based on their genetic relationships using 20 genome-wide microsatellite markers. Our analysis focused on the local Guangling Large Tail Sheep (GLLTS) breed and four introduced breeds: Hu Sheep (HS), Oula Tibetan Sheep (OLTS), Texel Sheep (TS), and Small Tail Han Sheep (STHLS). The results demonstrated that all microsatellite loci exhibited high levels of polymorphism, making them suitable for evaluating genetic diversity. The genetic parameters indicating that the five populations possess substantial genetic diversity. The genetic variation index (Fst) results among the five populations showed that moderate differentiation between populations. The genetic structure analysis results and the UPGMA clustering diagram were largely consistent. TS exhibited a distant genetic relationship with the other breeds, while HS and GLLTS shared the closest genetic relationship. Based on these genetic evidences, crossing GLLTS with TS or STHLS could potentially achieve a greater degree of heterosis. These research findings provide a molecular genetic foundation for analyzing the genetic diversity of sheep in Shanxi Province and offer guidance for hybrid breeding programs aimed at optimizing breed performance and resource conservation.