美国农业安全网内容与特点及其对韩国和中国农业政策的启示

美国之所以能发展成为世界超级农业大国与其成熟的农业政策体系有着密不可分的关系。在1933年颁布第一版农业法案后的近90年的历史演变中,美国已经发展了严密可靠的农业安全网,而农业安全网在稳定农产品价格和农业经营及保障农户收入中起到至关重要的作用。本文基于2018年颁布的美国农业法案,分析美国农业安全网之农产品计划、农作物保险计划和灾害援助计划三大主要内容及其特征,探讨不同形态小农国家如何从中借鉴并完善农业政策问题。研究表明,美国农业安全网牢固且具有弹性,具体体现为:对农户的保障范围和力度大;将安全网财政负担设置在可控范围内;农户的权利与义务同行;最大化兼顾国内农业生产环境和WTO国际规则;管辖机构间分工明确、协作紧密等特点。在农产品全球自由贸易加深、气候异常、疫情等因素威胁农产品价格和农户收入稳定的大环境下,中韩两国的农业政策仍有诸多不足,亟须完善。据此,给韩国农业的政策启示是:需制定更加多样灵活的农业补贴政策;扩大农产品支援品种;需形成政策间的协调联动机制;引入强制性财政支出方式。给中国农业政策带来的启示是:推进并完善农业信息化建设;制定长效且不乏弹性的农业政策法规与完善的财政补贴体系;加大财政支持,发展健全的农业保险制度;充分利用现有的WTO规则支持重要农产品生产,并积极筹备下一轮农业谈判为发展中国家的农业发展、粮食安全等议题争取更多权益。     

Cluster Membership, Centrality, Structural Holes and Innovation: A study on the Telecommunication Industry in the Republic of Korea

The research focuses on strategic alliances for innovation in the telecommunication industry in the Republic of Korea. The author reviews relevant literature and specifically investigates how cluster membership affects innovative performance. Later, he combines it with an endogenous factor - centrality. The main motivation is to investigate if the existing theories and theories, which are largely based in the Western context, applies in a collectivistic South Korean context.     

Demographic and Environmental Risk Factors for Exposure to Lawsonia intracellularis in Horses in Israel

Equine proliferative enteropathy (EPE) is an enteric disease of foals that is caused by Lawsonia intracellularis. Clinical cases have been reported worldwide; however, data regarding the epidemiology of L. intracellularis in horses are scarce. Thus far, L. intracellularis has not been reported in the Middle East. The objectives of this study were to determine whether the causative agent of EPE exists in horses in Israel and in the Palestinian Authority and to define environmental and demographic risk factors for exposure. Fecal and serum samples were collected from horses from various regions of the country. The presence of L. intracellularis in horses in Israel was determined by real-time polymerase chain reaction (PCR), and seroprevalence was determined by enzyme-linked immunosorbent assay. One fecal sample of 136 tested (0.7%), was PCR positive. Sixty-seven sera samples (30.5%) of 220 horses in sentinel farms had anti-L. intracellularis antibodies. Low seroprevalence was found in foals both from Israel and from the Palestinian Authority (4.2% and 13.3%, respectively). In logistic regression models, geographical locations, management type, and age were found to be significant risk factors associated with seroprevlaence to L. intracellularis. No significant correlation was found between environmental variables and L. intracellularis seroprevalence after controlling for management type. These results support the existence of L. intracellularis in horses in both Israel and the Palestinian Authority. The reasons for the relatively low prevalence are currently not known and may be the result of different management, low exposure to free-living animals, and differences in environmental variables affecting the bacterial burden.     

Caspase Activation,Hydrogen Peroxide Production and Akt Dephosphorylation Occur During Stallion Sperm Senescence

To investigate the mechanisms inducing sperm death after ejaculation, stallion ejaculates were incubated in BWW media during 6 h at 37°C. At the beginning of the incubation period and after 1, 2, 4 and 6 h sperm motility and kinematics (CASA), mitochondrial membrane potential and membrane permeability and integrity were evaluated (flow cytometry). Also, at the same time intervals, active caspase 3, hydrogen peroxide, superoxide anion (flow cytometry) and Akt phosphorylation (flow cytometry) were evaluated. Major decreases in sperm function occurred after 6 h of incubation, although after 1 h decrease in the percentages of motile and progressive motile sperm occurred. The decrease observed in sperm functionality after 6 h of incubation was accompanied by a significant increase in the production of hydrogen peroxide and the greatest increase in caspase 3 activity. Additionally, the percentage of phosphorylated Akt reached a minimum after 6 h of incubation. These results provide evidences that sperm death during in vitro incubation is largely an apoptotic phenomena, probably stimulated by endogenous production of hydrogen peroxide and the lack of prosurvival factors maintaining Akt in a phosphorylated status. Disclosing molecular mechanisms leading to sperm death may help to develop new strategies for stallion sperm conservation.     

Endometrial Explant Culture to Study the Response of Equine Endometrium to Insemination

Mating‐induced endometritis (MIE) is ubiquitous in the horse after natural mating and artificial insemination with frozen/thawed semen causing the most aggressive response. The majority of mares eliminate MIE 24–48 h after insemination. An endometrial explant culture was tested as a potential in vitro exemplar for sperm‐induced MIE. Endometrial prostaglandin F_2α (PGF_2α) secretion and expression of interleukin‐8 (IL‐8) were used as markers of inflammation. Endometrial explants were cultured from uteri collected from follicular phase mares. Explants were challenged with 1 or 10 × 10⁶ sperm/ml frozen/thawed semen, chilled semen, washed sperm or seminal plasma. Medium was collected 24 and 72 h after challenge and assayed for PGF_2α by radioimmunoassay. Treatment of endometrial explants with frozen/thawed, chilled semen or washed sperm did not change the secretion of PGF_2α compared with untreated controls. However, 24 h after challenge cultured explants expressed IL‐8. The in vitro endometrial explant system did not represent the in vivo response to semen when PGF_2α was used as a marker of inflammation, yet the use of gene expression as an inflammatory marker warrants further investigation.     

Blood calcium,glucose and haematology profiles of parturient bitches diagnosed with uterine inertia or obstructive dystocia

Bitches with dystocia most often present with clinical signs of uterine inertia (UI). The aetiology of myometrial dysfunction in most of these cases is still not elucidated. We compared blood ionized calcium (iCa) and glucose concentrations in bitches diagnosed with primary UI (PUI, n = 14), secondary UI (SUI, n = 6) or obstructive dystocia (OD, n = 6), and we described their haematology profiles. Bitches diagnosed with UI had a patent birth canal and delivered no puppies yet (PUI) or only part of the whole litter (SUI). The OD group had no UI and showed strong abdominal contractions. Blood iCa did not differ between the PUI, SUI and OD groups and was not influenced by litter size. There was a significant positive relationship (R² = .241, p = .013) between iCa concentrations and the dam's body weight. Glucose concentrations were also not significantly different between dystocia groups or influenced by body weight and litter size. Hypocalcaemia was detected in 11 bitches, and hypoglycaemia in two bitches. Pregnancy‐associated anaemia was seen in about one‐third of the bitches. Eight of 12 dogs had increased platelet counts, and ten had leukocytosis with mature neutrophilia. Although iCa did not differ between dystocia groups, low concentrations may have contributed to the development of UI in some of the small size bitches. Hypoglycaemia was uncommon, and therefore, we consider low glucose concentrations not to have played an important role in the pathogenesis of UI in our study population. Pregnancy‐associated anaemia, thrombocytosis, leukocytosis and mature neutrophilia were common findings in otherwise healthy bitches diagnosed with different forms of dystocia.