Search

ABSTRACT: The large-scale and intensive development of the meat pigeon breeding industry have resulted in the replacement of a large number of low-performance local breeds by a few breeds with excellent production performance. However, due to the characteristics of pigeon species that are monogamous, for which the W chromosome cannot be recovered and for which semen cannot be cryopreserved, the preservation of pigeon species is still mainly based on in-situ preservation. In this study, pigeons were classified into 6 classes of endangerment based on the criteria of the 100-year inbreeding coefficient of poultry populations in the “Assessment of Endangered Poultry Genetic Resources” (NY/T 2996–2016). The results show that when the generation interval was 1.5 yr, the number of ideal populations with the same gene frequency variance or the same heterozygosity decay rate of pigeons in class 1 to 5 was ≤149, 150 to 204, 205 to 316, 317 to 649 and ≥650. In random-reserved breeding, when the generation interval was 1.5 yr, the number of male (female) pigeons corresponding to class 1 to 5 was ≤74, 75 to 102, 103 to 157, 158 to 324 and ≥325. In family-equal-reserved breeding, when the generation interval was 1.5 yr, the number of male (female) pigeons corresponding to class 1 to 5 was ≤36, 37 to 50, 51 to 78, 79 to 162 and ≥163. When the generation interval was 1.5 yr, the inbreeding increments corresponding to class 1 to 5 were ≥0.00335, 0.00244 to 0.00334, 0.00159 to 0.00243, 0.00078 to 0.00158 and ≤0.00077; with the same population size, the inbreeding coefficient and inbreeding increment decreased with the increase of generation interval; the population effective content, inbreeding coefficient and inbreeding increment of family-equal-reserved pigeons were lower than those of random-reserved pigeons. The results of this study have certain reference value for analyzing the status quo of local and endangered species, constructing live gene banks and breeding farms of poultry genetic resources, and rescuing endangered species.

ABSTRACT: Milk citrate is regarded as an early biomarker of negative energy balance in dairy cows during early lactation and serves as a suitable candidate phenotype for genomic selection due to its wide availability across a large number of cows through milk mid-infrared spectra prediction. However, its genetic background is not well known. Therefore, the objectives of this study were to (1) analyze the genetic parameters of milk citrate; (2) identify genomic regions associated with milk citrate; and (3) analyze the functional annotation of candidate genes and quantitative trait loci (QTL) related to milk citrate in Walloon Holstein cows. In total, 134,517 test-day milk-citrate phenotypes (mmol/L) collected within the first 50 d in milk on 52,198 Holstein cows were used. These milk-citrate phenotypes, predicted by milk mid-infrared spectra, were divided into 3 traits according to the first (citrate1), second (citrate2), and third to fifth parity (citrate3+). Genomic information for 566,170 SNPs was available for 4,479 animals. A multiple-trait repeatability model was used to estimate genetic parameters. A single-step GWAS was used to identify candidate genes for citrate and post-GWAS analysis was done to investigate the relationship and function of the identified candidate genes. The heritabilities estimated for citrate1, citrate2, and citrate3+ were 0.40, 0.37, and 0.35, respectively. The genetic correlations among the 3 traits ranged from 0.98 to 0.99. The genomic correlations among the 3 traits were also close to 1.00 across the genomic regions (1 Mb) in the whole genome, which means that citrate can be considered as a single trait in the first 5 parities. In total, 603 significant SNPs located on 3 genomic regions (chromosome 7, 68.569–68.575 Mb; chromosome 14, 0.15–1.90 Mb; and chromosome 20, 54.00–64.28 Mb), were identified to be associated with milk citrate. We identified 89 candidate genes including GPT, ANKH, PPP1R16A, and 32 QTL reported in the literature related to the identified significant SNPs. These identified QTL were mainly reported associated with milk fatty acids and metabolic diseases in dairy cows. This study suggests that milk citrate in Holstein cows is highly heritable and has the potential to be used as an early proxy for the negative energy balance of Holstein cows in a breeding objective.

The prediction of power output from photovoltaic generation clusters is crucial for optimizing the dispatch of regional photovoltaic generation. Enhancing the accuracy of power prediction for photovoltaic power plant clusters requires the segmentation of distributed photovoltaic systems into clusters. This paper proposes a method for partitioning distributed photovoltaic clusters using a multiobjective genetic algorithm NSGA2, with spatial distance modularity and electricity similarity as optimization objectives to determine the optimal cluster partitioning scheme. The numerical examples and experimental results of the case analysis demonstrate a significant improvement in the convergence speed of the prediction system when employing the clustering partitioning method. This cluster segmentation algorithm significantly reduces the complexity and investment cost of the prediction system.

The existing optimization scheduling of regional CCHP system does not take into account the different control objectives and response characteristics of each unit under multiple operating states in the whole operation domain, so it is difficult to achieve the unified traction control of multiple operation stages of multiple units. To this end, this paper proposes a unified traction control strategy for multi-state operation of regional CCHP system. Based on the different control objectives and response characteristics CCHP unit under multiple states, a two-layer traction control strategy of the regional CCHP system and unit was established. The upper level takes into account the different control objectives and response characteristics of each unit under different operating states, and optimizes the target operating state of each traction unit. The lower level realizes the efficient traction control of each unit under the target operating state based on the optimization decision results. Finally, a simulation example is designed to verify that this paper can effectively consider the different control objectives and response characteristics of CCHP unit under different operating states to achieve the optimal traction control.

Abstract Circular RNAs (circRNAs) are a newly discovered class of endogenous non-coding RNAs that play an important role in growth and development by regulating gene expression and participating in a variety of biological processes. However, the role of circRNAs in porcine follicles remains unclear. Therefore, this study examined middle-sized ovarian follicles obtained from Meishan and Duroc sows at day 4 of the follicular phase. High-throughput RNA sequencing (RNA-seq) was utilized to construct circRNAs, and differential expression was identified. The findings were validated using reverse transcription PCR (RT-PCR) and DNA sequencing, GO and KEGG analyses were performed, and potential miRNA targets were identified. The RNA-seq identified a total of 15,866 circRNAs, with 244 differentially expressed in the Meishan relative to the Duroc (111 up-regulated and 133 down-regulated). The RT-PCR finding confirmed the RNA-seq results, and quantitative real-time PCR (qPCR) analysis examining a subset of the circRNAs showed that they are resistant to RNase R digestion. Bioinformatics analysis (GO and KEGG) showed that the host genes associated with the differentially expressed circRNAs are involved in reproduction and follicular development signaling pathways. Furthermore, many of the circRNAs were found to interact with miRNAs that are associated with follicular development. This study presents a new perspective for studying circRNAs and provides a valuable resource for further examination into the potential roles of circRNAs in porcine follicular development.

Borneo has gone through dramatic changes in geology and topography from the early Eocene until the early Pliocene and experienced climatic cycling during the Pleistocene. However, how these changes have shaped the present-day patterns of high diversity and complex distribution are still poorly understood. In this study, we use integrative approaches by estimating phylogenetic relationships, divergence time, and current and past niche suitability for the Bornean endemic land snail genus Everettia to provide additional insight into the evolutionary history of this genus in northern Borneo in the light of the geological vicariance events and climatic fluctuations in the Pleistocene. Our results show that northern Borneo Everettia species belong to two deeply divergent lineages: one contains the species that inhabit high elevation at the central mountain range, while the other contains lowland species. Species diversification in these lineages has taken place before the Pliocene. Climate changes during the Pleistocene did not play a significant role in species diversification but could have shaped contemporary species distribution patterns. Our results also show that the species-rich highland habitats have acted as interglacial refugia for highland species. This study of a relatively sedentary invertebrate supports and enhances the growing understanding of the evolutionary history of Borneo. Species diversification in Everettia is caused by geological vicariance events between the early Miocene and the Pliocene, and the distribution patterns were subsequently determined by climatic fluctuations in the Pleistocene.

[Introduction] In order to further improve the cruising ability of underwater equipment, the high specific energy electric energy system is the key to the problem. By comparing the impact of different fuel types on the specific energy of the system, the feasibility of underwater application of fuel cells is explored. [Method] By comparing and analyzing the characteristics of proton exchange membrane fuel cells and solid oxide fuel cells in different hydrogen storage and oxygen storage methods according to the index requirements, it is determined that the cathode side could meet the design requirements by using liquid oxygen supply and the anode side could adopt different supply methods, such as liquid hydrogen, organic liquid, methanol reforming, direct methanol and direct propane. [Result] Depending on the characteristics of different fuel cells, the relevant parameters of the tail gas treatment device are calculated and the feasible schemes of underwater fuel cell energy systems are comprehensively compared. The solid oxide fuel cell energy system with liquid oxygen and liquefied propane or organic liquid, the proton exchange membrane fuel cell with liquid oxygen and organic liquid could meet the design requirements. [Conclusion] The fuel cell energy system can significantly improve the specific energy of the energy system, and the fuel supply form is the main factor affecting the specific energy of the electric energy system.

The Vietnamese members of the genus Schistoloma are reviewed, and a checklist of all Schistoloma species is provided. Five species are recognised from Vietnam, including Schistoloma maydelineae new species, from Khánh Hoà Province. It is can be distinguished from all of its congeners by the strongly ribbed, conical shell and a white, conspicuous suture. Pinteria croesus Varga, 1972 is a synonym of Schistoloma inermis (Bavay & Dautzenberg, 1909). The latter species is recorded from China, Yunnan Province, for the first time. The Philippine Schistoloma subspecies of Bartsch are all considered synonyms of the nominotypical forms. [ABSTRACT FROM AUTHOR]