Mode of action of thiocyanate and iodide in relation to IAA metabolism

Whole plant studies have reaffirmed that of the halides and pseudohalide thiocyanate, only iodide and thiocyanate possess defoliant properties. Established work has indicated their possible involvement with IAA (indole-3-acetic acid). In vitro studies have suggested that IAA destruction is not through a direct interaction between IAA and the halides and pseudohalide but depends on their conversion to the halogen or pseudohalogen which can then destroy IAA. This may be accomplished by the peroxidase enzyme system for iodide only and docs not provide a mechanism for thiocyanate activity. However, both iodide and thiocyanate have chemical oxidation potentials suitable for their conversion to the halogen or pseudohalogen respectively via the photosynthetic apparatus. Hence, this would provide an explanation for then activity and the apparent inactivity of bromide, chloride and Buoride which would be oxidized very slowly or not at all.     

饲料中添加小苏打对甘南地区荷斯坦牛产奶量的影响

[目的]为研究饲料中添加小苏打对甘南地区荷斯坦牛产奶量的影响。[方法]选用27头健康、年龄、泌乳期一致的荷斯坦牛27头,随机分为3组,每组9头,设为对照组、试验A组、试验B组。分别饲喂8 kg青干草1、kg马铃薯;配合精料（见表2）;配合精料（见表2）＋150 g小苏打。[结果]试验A、B组比对照组日均多产奶3.75 kg和4.3 kg,分别提高了28%和32.1%（P〈0.05）,差异显著,试验B组较A组提高了0.55 kg（P〉0.05）,差异不显著。试验A、B组比对照组日均毛收入提高了7.53和9.65元,试验B组较A组日均毛收入提高了2.12元。[结论]在荷斯坦牛饲料中添加150 g小苏打能有效提高产奶量。     

欧拉羊与甘南山谷型藏羊杂交羔羊屠宰试验

通过对欧山F1和山谷型藏羊羔羊进行屠宰试验,结果得出:9月龄欧山F1羔羊宰前平均活重为38.25 kg,比本地山谷型藏羊羔羊宰前平均活重高10.17 kg,差异极显著(P<0.01)。欧山F1羔羊胴体重和屠宰率分别为15.14 kg和39.58%,比对照组高4.58 kg(P<0.01)和1.96个百分点,差异极显著。欧山F1羔羊净肉率、后腿比例和腰肉比例分别为29.65%、38.18%和12.99%,高于山谷型藏羊4.01、7.78和2.68个百分点;欧山F1羔羊GR值和眼肌面积分别为8.23 mm和12.74 cm2,高于山谷型藏羊1.48 mm和4.38 cm2。     

Is there a relationship between clinical presentation,diagnostic and radiographic findings and outcome in horses with osteoarthritis of the small tarsal joints?

Reasons for performing study: Despite the possibility that sound horses may have radiographic signs consistent with osteoarthritis of the small tarsal joints (OA‐STJ), a diagnosis of ‘bone spavin’ as a cause of lameness is often made based only on radiographic examination. Objectives: To determine whether severity of radiographic change and response to treatment are correlated with the duration and degree of lameness and the response to intra‐articular anaesthesia in horses with OA‐STJ. Methods: A retrospective study of all horses that showed a positive response to intra‐articular anaesthesia of the STJ was performed. Details of history, clinical presentation and diagnostic findings were recorded. Radiographs of affected tarsi were evaluated and scored independently by 2 observers. Follow‐up was via a telephone questionnaire with the owner. Statistical analysis was used to assess the association between the duration and degree of lameness, the response to intra‐articular anaesthesia and radiographic findings. Response to treatment was compared with the findings from the diagnostic work‐up. Results: Ninety‐one horses were included (61 unilateral and 30 bilateral lameness). Fifty‐nine percent of horses had been lame for over 2 months. There was no association between the duration and degree of lameness, or between duration or degree of lameness, intra‐articular anaesthesia and radiographic findings. Response to treatment showed a significant positive association with less severe radiographic changes within the tarsometatarsal (TMT) joint. Follow‐up was available for 48% of cases, with 52% horses returning to the same level of exercise. Conclusions: There is no association between the duration and degree of lameness, the response to intra‐articular anaesthesia and radiographic findings in horses with OA‐STJ. However, horses that improved following treatment tended to have less marked TMT joint pathology. Potential relevance: Response to intra‐articular anaesthesia should remain the gold standard for diagnosis of OA‐STJ. Predicting which cases are likely to improve following treatment remains difficult.     

Double-stranded RNA comprising the putative avocado virus 1 has a high degree of sequence homology to the avocado genome

The hypothesis that the double-stranded (ds) RNA isolated from avocado is indicative of infection by RNA plant viruses has never been proven. However, it has not been disproven and the different dsRNAs are still known as putative avocado viruses (AV) 1, 2 and 3. We have probed restriction fragments of avocado cellular DNA with cloned ³²P-labelled AV1-specific cDNA and discovered that the dsRNA nucleotide sequences are also present on plant DNA. Our evidence contradicts the hypothesis that viruses are responsible for the formation of the dsRNA species in avocado.     

乔科型藏羊遗传资源保护及制种供种体系建设思路

作者通过调查乔科型藏羊遗传资源现状,发现乔科型藏羊纯种数量当前仍有不断下降的风险,为了避免乔科型藏羊种群数量不断减少,作者分析了乔科型藏羊种质资源的优良特性,总结了开展乔科型藏羊遗传资源保护的意义,提出了乔科型藏羊遗传资源保护及制种供种体系建设的思路,并提出了建议。     

Biological characterisation of Australian isolates of chicken anaemia agent

Three Australian isolates of chicken anaemia agent (CAA) resisted treatment at 70 degrees C for 5 min and chloroform treatment. Although minor antigenic differences were detected using monoclonal antibodies to CAA, the Australian isolates were indistinguishable from the reference Cux-1 and Gifu-1 isolates in cross-immunofluorescence and cross-neutralisation tests employing polyclonal chicken antiserums. The Australian viruses were pathogenic for intramuscularly inoculated 1-day-old SPF chicks, but were less pathogenic for 7-day-old chicks. Thus the Australian isolates of CAA did not differ significantly in these properties from previously characterised CAA isolates from other continents.