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Weaning weight is a key indicator of the early growth performance of cattle. An understanding of the genetic mechanisms underlying weaning weight will help increase the accuracy of selection of breeding animals. In order to identify candidate genes associated with weaning weight in Simmental-Holstein crossbred cattle, this study generated RNA-Sequencing (RNA-seq) data from 86 crossbred calves (37 males and 49 famales) and measured their weaning weight and body size traits (wither height, body length, chest girth, rump width, and rump length). Differential gene expression analysis and weighted gene co-expression network analysis (WGCNA) were performed. A total of 498 differentially expressed genes (DEGs) were identified between the low weaning weight (LWW) group and the high weaning weight (HWW) group. Weaning weight was transcriptionally correlated (FDR < 0.05) with four of the eleven co-expression gene modules. By intersecting DEGs and hub genes of the four modules, we identified a final set of 37 candidate genes enriched in growth, development, or immune-related processes. In addition, one co-expression module was significantly correlated with all the five body size traits (P < 0.05), from which MX1 was identified as a key candidate gene through protein-protein interaction (PPI) analysis of hub genes. Further evidence from cattle transcriptome-wide association study analysis (TWAS) and human phenome-wide association study (PheWAS) validated significant associations of CACNA1S, SEMA7A, VCAN, CD101, CD19, and CSF2RB with growth and development traits (P < 0.05). Notably, CACNA1S and CD19 were also associated with typical immune traits such as B cell proliferation, differentiation, and activation. In conclusion, this study reveals new candidate genes significantly associated with weaning weight in Simmental-Holstein crossbred cattle, providing a basis for further exploration of the genetic mechanisms behind growth traits of cattle. [ABSTRACT FROM AUTHOR]

As an international standard pressure-measuring instrument, the absolute pressure piston manometer's working medium is gas, so the actual working process will be affected by many internal uncertainties and external disturbances, leading to its long stability time and poor performance. In this paper, a fuzzy linear active disturbance rejection control strategy (FLADRC) for absolute pressure piston manometers is proposed to address these problems. First, the characteristics of the main components are analyzed according to the actual working principle of the system to establish a theoretical model of the controlled system. Second, the corresponding linear active disturbance rejection controller (LADRC) is designed according to the model. The principle of fuzzy control is introduced to adaptively adjust the controller parameters of the LADRC in real time, which improves the disadvantages of the LADRC parameters, which are difficult to rectify and have poor immunity to disturbances due to fixed parameters, and the stability of the control method is subsequently demonstrated. Finally, a simulation model is built in the Simulink environment in MATLAB, and three different pressure operating points are selected for the corresponding experiments to make a comparative analysis with Kp, PID, and LADRC. The results show that FLADRC enables the absolute pressure piston manometer to achieve better stability and greater immunity to disturbances. This also verifies the effectiveness and feasibility of the control strategy in practical engineering applications. [ABSTRACT FROM AUTHOR]

Litter size is one of the important economic traits of livestock. Seasonal oestrus, ovulation and lambing of sheep have severely restricted the development of sheep farming in Xinjiang, China. The purpose of this study was to investigate the polymorphisms and genetic correlation between GRM1, GNAQ and HCRTR1 genes and the seasonal reproduction and litter size in three sheep breeds. The DNA mixed pool sequencing and PCR‐SSCP methods were used to detect single nucleotide polymorphisms (SNPs) of GRM1, GNAQ and HCRTR1 genes in seasonal oestrous (Kazakh and Chinese Merino [Xinjiang Junken type]) and perennial oestrous (Hu) sheep breeds. The association between genetic polymorphism and litter size was also analysed. The results showed that T945C in exon 2 of GRM1 gene, C589T in exon 2 of HCRTR1 gene and A191G in exon 2 of GNAQ gene were identified by Sanger sequencing, and three genotypes were existed in each SNP site, which all belonged to the synonymous mutation. GRM1 (CC), GNAQ (GA) and HCRTR1 (TC) were the dominant genotypes of seasonal reproduction and litter size in Kazakh sheep and Chinese Merino sheep, respectively, while, in perennial oestrous Hu sheep populations, the dominant genotypes were GRM1 (TC), GNAQ (GA) and HCRTR1 (TC), respectively, and association analysis also confirmed the results. The above results implied that GRM1, GNAQ and HCRTR1 genes are significantly associated with lambing traits in Kazakh, Chinese Merino and Hu sheep. Among them, the locus of GRM1 (T945C), GNAQ (A191G) and HCRTR1 (C589T) might be considered as a potential molecular marker, which controls seasonal reproduction and litter size in sheep. [ABSTRACT FROM AUTHOR]