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The introduction of exotic breeds and the cultivation of new lines by breeding companies have posed challenges to native chickens in South China, including loss of breed characteristics, decreased genetic diversity, and declining purity. Understanding the population genetic structure and genetic diversity of native chickens in South China is crucial for further advancements in breeding efforts. In this study, we analyzed the population genetic structure and genetic diversity of 321 individuals from 10 different breeds in South China. By comparing commercial chickens with native ones, we identified selection signatures occurring between local chickens and commercial breeds. The analysis of population genetic structure revealed that the native chicken populations in South China exhibited a considerable level of genetic diversity. Moreover, the commercial lines of Xiaobai chicken and Huangma chicken displayed even higher levels of genetic diversity, which distinguished them from other native varieties at the clustering level. However, certain individuals within these commercial varieties showed a discernible genetic relationship with the native populations. Notably, both commercial varieties also retained a significant degree of genetic similarity to their respective native counterparts. In order to investigate the genomic changes occurring during the commercialization of native chickens, we employed 4 methods (Fst, ROD, XPCLR, and XPEHH) to identify potential candidate regions displaying selective signatures in Southern Chinese native chicken population. A total of 168 (identified by Fst and ROD) and 86 (identified by XPCLR and XPEHH) overlapping genes were discovered. Functional annotation analysis revealed that these genes may be associated with reproduction and growth (SAMSN1, HYLS1, ROBO3, FGF14, PRSS23), musculoskeletal development (DNER, MYBPC1, DGKB, ORC1, KLF10), disease resistance and environmental adaptability (PUS3, CRB2, CALD1, USP15, SGCD, LTBP1), as well as egg production (ADGRB3, ACSF3). Overall, native chickens in South China harbor numerous selective sweep regions compared to commercial chickens, enriching valuable genomic resources for future genetic research and breeding conservation. [ABSTRACT FROM AUTHOR]

Meat quality traits are essential for producing high-quality broilers, but the genetic improvement has been limited by the complexity of measurement methods and the numerous traits involved. To systematically understand the meat quality characteristics of different broiler breeds, this study collected data on slaughter performance, skin color, fat deposition, and meat quality traits of 434 broilers from 12 different breeds in South China. The results showed that there was no significant difference in the live weight and slaughter weight of various broiler breeds at their respective market ages. Commercial broiler breeds such as Xiaobai and Huangma chickens had higher breast muscle and leg muscle rates. The skin and abdominal fat of Huangma chickens cultivated in the consumer market in South China exhibited significantly higher levels of yellowness compared to other varieties. Concerning fat traits, we observed that Wenchang chickens exhibited a strong ability to fat deposition, while the younger breeds showed lower fat deposition. Additionally, there were significant positive correlations found among different traits, including traits related to weight, traits related to fat, and skin color of different parts. Hierarchical clustering analysis revealed that fast-growing and large broiler Xiaobai chickens formed a distinct cluster based on carcass characteristics, skin color, and meat quality traits. Principal component analysis (PCA) was used to extract multiple principal components as substitutes for complex meat quality indicators, establishing a chicken meat quality evaluation model to differentiate between different breeds of chickens. At the same time, we identified 46, 22, and 20 SNP loci and their adjacent genes that were significantly associated with muscle mass traits, fat deposition, and skin color through genome-wide association studies (GWAS). The above results are helpful for systematically understanding the differences and characteristics of meat quality traits among different breeds. [ABSTRACT FROM AUTHOR]

As a Chinese local chicken breed, Hongshan chickens have 2 kinds of tail feather phenotypes, normal and taillessness. Our previous studies showed that taillessness was a sex-linked dominant trait. Abnormal development of the tail vertebrae could be explained this phenomenon in some chicken breeds. However, the number of caudal vertebrae in rumpless Hongshan chickens was normal, so rumplessness in Hongshan chicken was not related to the development of the caudal vertebrae. Afterwards, we found that rumplessness in Hongshan was due to abnormal development of tail feather rather than abnormal development of caudal vertebrae. In order to understand the genetic foundation of the rumplessness of Hongshan chickens, we compared and reanalyzed 2 sets of data in normal and rumpless Hongshan chickens from our previous studies. By joint analysis of genome-wide selection signature analysis and genome-wide association approach, we found that 1 overlapping gene (EDIL3) and 16 peak genes (ENSGALG00000051843, ENSGALG00000053498, ENSGALG00000054800, KIF27, PTPRD, ENSGALG00000047579, ENSGALG00000041052, ARHGEF28, CAMK4, SERINC5, ENSGALG00000050776, ERCC8, MCC, ADAMTS19, ENSGALG00000053322, CHRNA8) located on the Z chromosome was associated with the rumpless trait. The results of this study furtherly revealed the molecular mechanism of the rumpless trait in Hongshan chickens, and identified the candidate genes associated with this trait. Our results will help to improve the shape of chicken tail feathers and to rise individual economic value in some specific market in China. [ABSTRACT FROM AUTHOR]

• Constructed an operation architecture of the coupling of energy supply and demand. • Established the comprehensive demand response mechanism based on time-sharing energy prices. • Established the minimum carbon emission cost economic scheduling model as an objective function. • The scheduling method could achieve the goal of low-carbon economic dispatch. Aiming at the problems of low energy utilization and environmental pollution in China's livestock and poultry breeding industry under the carbon peaking and carbon neutralization goals, this paper proposes an optimal scheduling model for multi-energy coupling integrated energy system with ladder-type carbon trading mechanism and demand response. First, based on the construction of a reward and punishment model with ladder-type carbon trading mechanism, this paper explores the potential interaction between the coupling ability of multiple heterogeneous energy sources and carbon emissions in consideration of the impact of carbon capture equipment on carbon emissions. Second, in view of the diversity and complexity of demands for agricultural energy supply, the energy supply side equipment model and the comprehensive demand response model of electricity, heat, and gas are established, and a low-carbon economic scheduling model of integrated agricultural energy system is proposed, aiming at minimizing the total operation cost of the system. Finally, the model is solved by CPLEX, and the coupling system of a 6-node power distribution network, a 6-node gas network, and a 4-node heat supply network is used to verify the effectiveness of the proposed model and method and optimize the operation of the integrated agricultural energy system. [ABSTRACT FROM AUTHOR]

Yellow-feather broilers take a large portion of poultry industry in China due to its meat characteristics. Improving the growth traits of yellow-feathered broilers will have great significance for the Chinese poultry market. The current study was designed to investigate the potential genetic factors using the weighted single-step genome-wide association study (wssGWAS) method, which takes consideration of more factors including pedigree, sex, environment and has more accuracy than traditional GWAS. The yellow-feather dwarf chickens from Wens Nanfang Poultry Breeding Co. Ltd. were revolved to recode 9 growth traits: Average daily gain (ADG), body weight (BW) at 45 d, 49 d, 56 d, 63 d, 70 d, 77 d, 84 d, 91 d for analysis. For the results, the region 4.63 to 5.03 Mb on chromosome 15, which was the QTL overlapped in BW45, BW49, BW56, BW63, BW84, might be the crucial genetic region for growth traits. Seven GO terms and 3 KEGG pathways, GO:0005200, GO:0005882, GO:0045111, GO:0099513, GO:0099081, GO:0099512, GO:0099080, KEGG:gga04020, KEGG:gga04540, KEGG:gga04210, were detected to relevant with growth traits. The genes enriched in these biological processes (NRAS, TUBB1, ADORA2B, NTRK3, NGF, TNNC2, F-KER, LOC429492, LOC431325, LOC431324, LOC396480) might have the function in growth of yellow-feather broilers. [ABSTRACT FROM AUTHOR]

Subgroup K avian leukosis virus (ALV-K) is a new subgroup of avian leukosis virus (ALV) first identified in Chinese indigenous chickens in recent years. In this study, an ALV-K strain was isolated from Luhua chicken in Shandong province, China, and designated SD20LH01. The full-length genomic sequence of SD20LH01 was 7491 bp, which had the highest homology with ALV-K reference strains GDFX0601, GDFX0602 and GDFX0603. The nucleotide homology of env gene of SD20LH01 with reference strains of subgroup A, B, C, D, E, and J was ranged from 57.1 to 93.2%, while 94.1 to 99.4% with other ALV-K reference strains. The nucleotide difference of SD20LH01 mainly clustered with gp85 gene and U3 sequence when compared with the reference strain of ALV-K. In order to investigate the pathogenicity of SD20LH01, SPF chicken embryos were infected by yolk sac inoculation, and 1-day-old chickens were infected by intraperitoneal inoculation of SD20LH01. The results showed that yolk sac inoculation of SD20LH01 could induce persistent viremia, growth retardation and reduce the immune response to NDV and AIV-H9 vaccines. However, intraperitoneal inoculation in 1-day-old chickens could only induce a low level of viremia. In addition, no tumors were found in infected chickens during the animal experiments. This study enriched the genomic sequence data of ALV-K isolated in Chinese indigenous chickens, and laid a foundation for further study on the pathogenesis and prevention of ALV-K. [ABSTRACT FROM AUTHOR]

China is the world's largest livestock and poultry breeding country. Heavy metal trace element additives are widely used to prevent animal diseases and promote their growth. China produces approximately 3.8 billion tons of livestock and poultry manure annually, and untreated livestock and poultry manure causes a large amount of heavy metal elements to enter the soil environment. Currently, there is limited research on the accumulation of heavy metals in the soil due to the continuous application of livestock and poultry manure, the resulting pollution risk and the negative effects on soil ecology sustainability. This study thoroughly investigated the effects of livestock and poultry manure on the composition and function of soil microbial, and heavy metal resistance genes using 16S and metagene sequencing and 6 years of field experiments. The application of livestock and poultry manure for 6 consecutive years increased the accumulation of zinc (Zn), copper (Cu), mercury (Hg), and chromium (Cr) in the soil at the experimental sites, and cadmium (Cd) and Hg had higher potential risk levels (single potential ecological risk coefficients (E r i) of Hg and Cd were 190.49–336.52 and 385.43–468.52, respectively). Firmicutes and Zoopagomycota were significantly correlated with the soil Zn and Cd contents and pH. After continuous application of manure, the relative abundance of Hg resistance genes (merA) in soil increased by 7.3–8.2 times compared with inorganic feitilizer treatment (IF), and Cu resistance genes (copF and actP) increased by 2.45–5.45 times and 3.8–4.6 times. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt2) and metagenomic function prediction indicated that resistance genes, antioxidant response, and metal output played an important role in heavy metal bioresistance and biotransformation. This work presented heavy metal contents, microbial composition and resistance genes in continuous application of livestock and poultry manure in China, and these data will be of great use in the surveillance, maintenance, and biological removal of heavy metals in manure. [Display omitted] • Continuous application of manure, soil Cd and Hg had higher potential risk levels. • The relative abundance of soil Mortierella was increased. • Relative abundance of merA and actP was increased by 7.3–8.2 and 3.8–4.6 times. • Resistance genes, etc. played an important role in heavy metal biotransformation. [ABSTRACT FROM AUTHOR]

Pullorum disease is characterized by white diarrhea resulting from infection by S. Pullorum, but arthritis associated with S. Pullorum infection has become increasingly frequent recently, especially in Chinese native chicken flocks. In this study, we isolated and identified 4 S. Pullorum strains from the Qingjiaoma chicken breeders with arthritis symptoms. The LD 50 of the isolate 20JS04 was 1.33 × 106 CFU, which was considered as a highly virulent strain in chicks. Reproducible arthritis symptoms were observed in the experimentally chickens infected with the isolate 20JS04, and the disease occurrence was 27.78% (5/18). In addition to the characteristics of high virulence and induced-arthritis, our results confirmed that the arthritis-causing isolate 20JS04 had greater negative impact on BW, ADFI, and ADG, compared with the white diarrhea-causing S. Pullorum standard strain CVCC526 (P < 0.05). These results suggest that the pathogenic diversity of S. Pullorum in China deserves more attention and stringent measures should be taken to control salmonellosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • In-situ synthesis/purification integration (ISSPI) strategy was adopted for NH 4 + and PO 4 3- removal. • The strategy was achieved based on constructing Mg-doped tricalcium aluminate (Mg-C 3 A). • Mg-C 3 A exhibited excellent capacities for NH 4 + (43.0 mg·g−1) and PO 4 3- (20.2 mg·g−1). • The hydration properties of Mg-C 3 A played vital roles in the ions removal/recovery. • ISSPI strategy using Mg-C 3 A was compelling for authentic wastewater treatment. Simultaneous capture of ammonium (NH 4 +-N) and phosphate (PO 4 3−-P) in digested piggery wastewater is of great urgency yet remains a challenge. Recently, the in-situ synthesis/purification integration (ISSPI) strategy, with the essence of converting contaminations to high value-added products, has aroused great enthusiasm in the environmental remediation realm. In the present work, we employed ISSPI method for simultaneous elimination and recovery of NH 4 + and PO 4 3- from digested piggery wastewater based on the construction of a novel material system, i.e. , Mg-doped tricalcium aluminate (Mg-C 3 A), which coupled the features of cement-based material tricalcium aluminate (Ca 3 Al 2 O 6 , C 3 A) and Mg dopants. The released metal cations (Ca2+, Mg2+, and Al(OH) 4 −) of Mg-C 3 A were expected to act as precipitation agents to capture NH 4 + and PO 4 3− via the formation of Ca(NH 4) 2 (HPO 4) 2, MgHPO 4 ·3H 2 O or AlPO 4 ; OH− established an alkaline environment for the enhancement of NH 4 + removal via neutralization; Mg2+ played a major role in the recovery of NH 4 + and PO 4 3−, with the formation of valuable struvite as fertilizer. Benefited by these functions, Mg-C 3 A exhibited superior removal capacity for NH 4 + (43.0 mg·g−1) and PO 4 3− (20.2 mg·g−1). More importantly, the ISSPI method using Mg-C 3 A was prospective to be applied for authentic effluent treatment as demonstrated by response surface methodology (RSM), with the concentration of both ions down to the discharge standard of livestock and poultry breeding, China (80 mg·L−1 for NH 4 +; 8 mg·L−1 for PO 4 3−). This research provided an alternative and promising approach for the simultaneous removal and recovery of NH 4 + and PO 4 3− from digested piggery effluent, shedding light on environmental remediation. [ABSTRACT FROM AUTHOR]