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Rice–crayfish coculture systems (RCSs) have been widely promoted in China as an efficient circular agriculture model that can simultaneously improve rice quality, raise the efficiency of utilization of resources, and increase farmers' incomes. However, the herd behavior of farmers in the adoption of the rice–crayfish coculture system warrants more attention, as the rational adoption of this system by farmers is a prerequisite for achieving the above objectives. This paper analyses the formation mechanism of farmers' herd behavior based on information cascade theory. Using micro-survey data from 603 farmers in China and a bivariate probit model, we examine the existence of herding effects in the adoption of RCSs by farmers and the inhibitory effect of information acquisition capability on herd behavior. To address possible endogeneity issues, we also conducted a robustness test using the IV-probit model. Furthermore, we tested for between-group differences in agricultural income between farmers with herding adoption and non-herding adoption. The study reveals that the larger the number of prior adopters, the higher the probability of blind adoption behavior by farmers, indicating the existence of a herd effect. Information acquisition ability could significantly inhibit the herd behavior of farmers in the adoption of RCSs. We also found that farmers' herd behavior in the adoption of these systems was not economically rational. Based on the research findings, we proposed several constructive suggestions for policy perfection. [ABSTRACT FROM AUTHOR]

Currently, PRRSV-1 causes a large number of clinical infections in Chinese swine herds, and the prevalence of new strains has presented great challenges. In this study, the novel PRRSV-1 strain SL-01 was isolated, with a genome length of 14,978 bp, and genetic evolution analysis revealed that it belonged to a new subtype branch. Sequence homology analysis showed that the strain was only 82.2%–86.7% identical to the current classical PRRSV-1 strains. In particular, the novel strain exhibited a unique deletion pattern in Nsp2. In addition, GP3 and GP4 of the SL-01 strain showed four consecutive amino acid deletions in the highly variable regions at amino acids 243–248 and 63–68, respectively. Further challenges in piglet and pregnant sow demonstrated that the SL-01 strain could cause the piglet fever and death but less pathogenic to pregnant sow. Overall, the characterization and pathogenicity of a novel PRRSV-1 strain were first explored and provide a prevention for pig farms. [ABSTRACT FROM AUTHOR]

This paper explores the influence of fund managers' social networks on the herding behavior of securities investment funds (SIFs) in China. Using the data of Chinese SIFs in recent years as a sample, it adopts the CSAD model to measure SIFs' herding behavior. Combining indicators such as social network centrality, constraint, and size, it constructs a regression model of the influence of fund managers' social networks on the herding behavior of SIFs and conducts an empirical study. The heterogeneity of this influence is investigated in four dimensions, degree of herding behavior, gender, diploma, and region. The results show that: (i) The larger the social network size of fund managers, the lower the degree of herding behavior of fund managers, but the effect of the network constraint on the degree of herding behavior is not significant. (ii) When the degree of herding behavior of SIFs is high, the effect of network size on herding behavior is heterogeneous. (iii) The relationship between the social network of male fund managers and the degree of herding behavior is more significant than that of female fund managers, as network size is significant for male fund managers, while the regression results of social network centrality, network constraint, network size, and the degree of herding behavior of female fund managers are all not significant. (iv) The social network of the fund manager with a master's degree has a significant impact on the herding behavior of SIFs, which is not significant in fund managers with Ph.D. [ABSTRACT FROM AUTHOR]

Integrating pig production stability and pollution control is a matter of social livelihood and green development. This paper estimates the policy effectiveness of environmental regulation based on the big data of Chinese government websites and combines the pig production data of various provinces in China from 2008 to 2018 to construct a mediating effect model, empirically analyzing the relationship between environmental regulations, herd structure, and pig production. Research shows: (1) Improving environmental regulations in the short term will increase the slaughter of pigs, but in the long run it will decrease first and then increase; (2) At this stage, environmental regulations can increase the slaughter of pigs by changing the herd structure; (3) Reasonable adjustment of the herd structure can effectively increase the slaughter of pigs; (4) The herd structure can be used as a supplementary monitoring indicator to stabilize the supply of pigs. Combine it with the change rate of sow stock to provide early warning of fluctuations in pig production, and the early warning herd structure values are 0.0980 and 0.1135. There are two key initiatives to achieve supply and price stability in the pig industry that taking into account environmental protection: first, an industrial regulation instrument based on the herd structure needs to be established; second, an early warning system for pig production fluctuations should be established with reference to the early warning system for pork price fluctuations. [ABSTRACT FROM AUTHOR]

Background: Nitrate leaching to groundwater and surface water and ammonia volatilization from dairy farms have negative impacts on the environment. Meanwhile, the increasing demand for dairy products will result in more pollution if N losses are not controlled. Therefore, a more efficient, and environmentally friendly production system is needed, in which nitrogen use efficiency (NUE) of dairy cows plays a key role. To genetically improve NUE, extensively recorded and cost-effective proxies are essential, which can be obtained by including mid-infrared (MIR) spectra of milk in prediction models for NUE. This study aimed to develop and validate the best prediction model of NUE, nitrogen loss (NL) and dry matter intake (DMI) for individual dairy cows in China. Results: A total of 86 lactating Chinese Holstein cows were used in this study. After data editing, 704 records were obtained for calibration and validation. Six prediction models with three different machine learning algorithms and three kinds of pre-processed MIR spectra were developed for each trait. Results showed that the coefficient of determination (R2) of the best model in within-herd validation was 0.66 for NUE, 0.58 for NL and 0.63 for DMI. For external validation, reasonable prediction results were only observed for NUE, with R2 ranging from 0.58 to 0.63, while the R2 of the other two traits was below 0.50. The infrared waves from 973.54 to 988.46 cm−1 and daily milk yield were the most important variables for prediction. Conclusion: The results showed that individual NUE can be predicted with a moderate accuracy in both within-herd and external validations. The model of NUE could be used for the datasets that are similar to the calibration dataset. The prediction models for NL and 3-day moving average of DMI (DMI_a) generated lower accuracies in within-herd validation. Results also indicated that information of MIR spectra variables increased the predictive ability of models. Additionally, pre-processed MIR spectra do not result in higher accuracy than original MIR spectra in the external validation. These models will be applied to large-scale data to further investigate the genetic architecture of N efficiency and further reduce the adverse impacts on the environment after more data is collected. [ABSTRACT FROM AUTHOR]

In the financial market, because of information asymmetry, investors often ignore private information. Herding behavior in financial markets has become an important research branch of behavioral finance. China stock market has implemented the Shanghai-Hong Kong Stock Connect (SHKSC) policy and introduced mature funds, however, has it alleviated the herd effect? This article empirically verifies the existence of China's stock market before and after the implementation of the SHKSC policy. The research in this article found that the implementation of the SHKSC policy has not changed herding behavior. On the contrary, the herding effect has become more serious. It is further found that investors have no obvious investment preference for the industry to which the stock belongs. Investor investment is in line with the phenomenon of "slow rise and sharp fall." When stock prices fall, the herd effect of the Chinese stock market is also more obvious. [ABSTRACT FROM AUTHOR]

Malignant catarrhal fever (MCF) is a fatal lymphoproliferative disease that represents a serious problem in the deer‐rearing industry. To better understand an MCF‐like disease that has emerged in northern China since 2015, we investigated ten cases by documenting clinical and epidemiological data and analysing causative agents and histopathological changes. In addition, a retrospective screen for Macavirus DNA and a questionnaire‐based survey were conducted. Epizootic MCF in Chinese sika deer herds has emerged with a low morbidity of 3.8% (95% CI: 2.5%–5.1%) and a high mortality of 93.2% (95% CI: 86.6%–99.9%). The disease course varied from 3 to 12 days. Aetiologically, OvHV‐2 was predominant in the MCFV, accounting for most MCF cases (21/23). In contrast, only two CpHV‐2 isolates were phylogenetically closely related to CpHV‐2. Diarrhoea and nasal discharges were the most frequent manifestations, although clinical signs varied in some cases. Pathologically typical lesions of haemorrhage, necrosis and lymphoid cell infiltration were readily observed in a variety of organs. Vasculitis caused by vascular and perivascular lymphoid cell infiltration was common. The retrospective survey suggested a low positive rate (3/275) of MCFV DNA in peripheral blood lymphocytes (PBL). The questionnaire‐based survey suggested the disease was neglected by local veterinarians, who did not acknowledge the risk of co‐rearing deer with reservoir species. Collectively, the emerging epizootic MCF in Chinese sika deer herds remains neglected, emphasizing the urgency of initiating full‐field diagnoses and control strategies. [ABSTRACT FROM AUTHOR]

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The emerging porcine circovirus type 3 (PCV3) has been reported in Chinese swine herds since 2017. We performed a nationwide investigation on the prevalence of PCV3 in pig breeding farms and slaughterhouses in China. A total of 4,040 tonsil samples were collected from 89 farms in 25 provinces, and 1,419 lymph node samples were collected from 50 slaughterhouses in 27 provinces. The PCR results showed that in pig breeding farms, the positive rate was 41.6% (37/89) at the farm level and 5.0% (201/4040) at the individual level. In the slaughterhouses, the positive rate was 62.0% (31/50) at the farm level and 8.0% (114/1419) at the individual level. The PCR‐positive samples were further sequenced, and 19 new PCV3 isolates were identified. The complete genomes of the 19 virus isolates showed 97.4%–99.7% nucleotide identity with other PCV3 isolates. The phylogenetic analysis revealed that the 19 isolates were divided into PCV3a and PCV3b genotype clusters based on the PCV3 complete genome sequences. This study indicated that PCV3 has spread extensively in both pig breeding farms and slaughterhouses. The positive rate of PCV3 was higher in eastern China compared to other regions in China. Furthermore, this study will help us understand the prevalence and genetic variation of PCV3 in Chinese swine herds. [ABSTRACT FROM AUTHOR]