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In this paper, a time-delayed fractional order adaptive sliding mode control algorithm is proposed for a two-wheel self-balancing vehicle system. The closed-loop system is proved based on the Lyapunov-Razumikhin function. The switching function is designed to make the system robust when facing uncertainties and external disturbances. It is designed to avoid monotonically increasing gains and can handle state-dependent uncertainties without a prior bound. The two-wheel self-balancing vehicle used in the experiment consists of a gyroscope MPU-6050 and accelerometer, a motor driving circuit composed of a motor driving chip TB6612FNG, and STM32F103x8B that is selected as the control core. The experimental results show that the time-delayed fractional order adaptive sliding mode control algorithm can make the vehicle achieve autonomous balance and quickly restore its stable state while appropriate disturbance is introduced.

This study compared six models, namely the Gaines, Sikka, Nelder, Wood, Dhanoa and Hayashi models, for the estimation of 305 days milk yield in Chinese Holstein cattle. We compared their ability to reliably predict 305-day lactation yield from incomplete (3 or 6 test-day (TD)) records. Our findings revealed that the accuracies (ACC) were 0.6655–0.9948, 0.8652–0.9977 and 0.9169–0.9968, whereas the mean square errors (MSE) were 0.0121–2.4807, 0.0139–1.0716 and 0.0170–0.5528 when 3 TD records were used in the first, second and higher lactations, respectively; when 6 TD records were used, the ACC were 0.8800–0.9992, 0.8742–0.9998 and 0.7950–0.9996, whereas the MSE values were 0.0017–0.3348, 0.0011– 0.8605 and 0.0021–1.4869 in the first, second and higher lactations, respectively. All the models were fitted more accurately with 6 TD than 3 TD records. Further analysis revealed that the curves made by the Nelder, Wood and Dhanoa models were close to the actual curves. These three models can be used to predict the 305-day yield for management decisions in farms and for the genetic evaluation of Chinese Holstein cattle.

High immune response (HIR) cows have a balanced and robust host defense and lower disease incidence, and immune response is more important to consider for selecting young sires than for selecting cows. The protective immune response against foot-and-mouth disease (FMD) virus infection is T-cell-independent in an animal experimental model. However, there is no convenient method to select young sires with a HIR to FMD virus. In this study, 39 healthy Holstein young sires were vaccinated with the trivalent (A, O and Asia 1) FMD vaccine, and T-lymphocyte subsets in peripheral blood lymphocytes (PBLs) were detected using flow cytometric analysis before and after vaccination. The expression of interferon-gamma (IFN-γ), interleukin-2 (IL-2), IL-4, and IL-6 mRNA in PBLs was analyzed after stimulation by lipopolysaccharide (LPS) or Concanavalin A (ConA) after vaccination. According to the percentage of CD4+ lymphocyte and CD4/CD8 ratio after vaccination for selecting the HIR young sires, the results showed that the percentages of CD3+, CD4+, CD3+CD4+ lymphocytes and the CD4/CD8 ratio in the HIR group were higher compared to those in the medium immune response (MIR) and low immune response (LIR) groups before vaccination. Additionally, the percentage of CD4+ lymphocytes and the CD4/CD8 ratio after vaccination were positively associated with the expression level of IFN-γ mRNA in the PBLs after stimulation by LPS. In conclusion, the in vitro expression level of IFN-γ mRNA in the PBLs stimulated by LPS may serve as a parameter for selecting young sires with a HIR to FMD virus.

Single-nucleotide polymorphisms (SNPs) of exon 8 of the GHR gene were detected in Chinese Holstein cows by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). The results showed that exon 8 of the GHR gene digested byTasI could be divided into two kinds of alleles and three kinds of genotypes. The frequencies of allele A and T were 0.6339 and 0.3661, respectively. The frequencies of genotypes AA, AT and TT were 0.459, 0.350 and 0.191, respectively. Sequencing showed one single nucleotide mutation T→A at 4962 bp of the gene in genotype TT when compared with genotype AA, and this mutation resulted in an amino acid change of phenylalanine (TTT)→tyrosine (TAT). The result of χ2testing indicated that the genotypic frequency of the GHR gene digested byTasI did not fit with Hardy–Weinberg equilibrium in this population (PP

Protein degradation in bovine milk affects the quality of dairy products. Alpha 1-antitrypsin (AAT) can protect vulnerable elastic tissues from degradation by neutrophil elastase. The aim of this study was to assess the association of polymorphisms in bovine AAT gene with milk yield and milk composition in Chinese Holstein. Traits analyzed were fat percentage, protein percentage, 305-day milk yield and somatic cell score (SCS). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), created restriction site-polymerase chain reaction (CRS-PCR) and allele specific-polymerase chain reaction (AS-PCR) methods were used to genotype five loci in coding regions of the sequence, including position 5504, 5609, 5624, 5747 and 8178 in Chinese Holstein. The five mutations were all silent mutation that caused no alteration in the amino acid sequence. In order to determine the relationship between the polymorphisms of the AAT gene and milk production traits and SCS, the General Linear Model (GLM) procedure from the Statistical Analysis Software was used. SNP5504 affected milk fat percentage, SNP8178 affected milk protein percentage and SNP5609 and SNP5624 affected 305-day milk yield. These results suggest that AAT is a candidate gene that influences milk production traits and it could be implemented in breeding programmes to improve the production performance of Chinese Holstein cattle.Keywords: Dairy cattle, α1-protease inhibitor, SNPs, milk traits, somatic cell score