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This paper is motivated by the observation that Southern governments start to take responsibility for a more sustainable production of agricultural commodities as a response to earlier private initiatives by businesses and non-governmental organizations (NGOs). Indonesia is one of the leading countries in this respect, with new public sustainability regulations on coffee, cocoa and palm oil. Based on the concept of governance capacity, the paper develops an evaluation tool to answer the question whether the new public regulation on sustainable palm oil (ISPO) may become a viable alternative to private regulation. ISPO embraces a tremendous governance challenge as thousands of companies and millions of smallholder farmers are expected to participate. It is concluded that, although ISPO has initiated a process of change, it has not yet developed its full potential. The main reason regards ISPO’s rather loose problem definition, weak authority of the implementing organization, and the fact that the reliability of ISPO is still too low to convince (parts) of the global market. ISPO may therefore face difficulties in meeting its own targets and solving palm-oil related problems, such as deforestation, biodiversity loss, greenhouse gas emissions, and social conflicts between big plantations and local communities. The main governance challenge regards combining a more authoritative implementation mechanism with a convincing balance between sustainability objectives and economic interests of the sector.  相似文献   
2.
Our objective was to study the relationships between colostral somatic cell counts (SCC, a criterion for mastitis severity at parturition) and early calf growth, blood indicators of immunity, and pre‐weaning faecal and health states. Sixty‐nine Holstein cows were assigned to three groups of greater (n = 21, 5051 × 103), medium (n = 38, 2138 × 103) and lower (n = 10, 960 × 103) colostral SCC (per ml) in a completely randomized design. Calves received 2 l of colostrum on day 1, and jugular blood was sampled at birth, at 3 h after the first colostrum feeding and at 42 days of age for immunoglobulin G (IgG) measurements. Calves were fed transition milk from their dams until 3 days of age and whole milk from 4 to 60 days of age twice daily at 10% of body weight. Health status and faecal physical scores were recorded daily for 42 days. Increased colostral SCC was associated with increased serum IgG at parturition. Colostral pH increased and fat percentage decreased linearly with the rising SCC. Feeding colostrum with greater SCC was associated with reduced serum IgG concentrations at 3 h after first colostrum feeding, greater incidences of diarrhoea and compromised health status during the first 42 days of age, and reduced weaning weight gain, but had no effects on calf body length and withers height. Colostral volume and percentages of protein, lactose, solids‐non‐fat, total solids and IgG were comparable among groups. Results suggest a role for SCC, as an indicator of mastitis and colostral health quality, in affecting calf health. As a result of the novelty of calf health dependence on colostral SCC found, future studies to further characterize such relationships and to uncover or rule out possible mediators are required before colostral SCC could be recommended for routine on‐farm use in managing dry cow and calf production.  相似文献   
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The consequences of recurrent drought events compared with a single drought, and drought's interaction with deliberate selfing compared with open-pollination on postdrought recovery and persistence of smooth bromegrass, are not clear. This research was conducted to investigate the effects of recurrent drought stresses compared with a single drought on stress response, poststress recovery and persistence of full-sib and half-sib progenies of smooth bromegrass. During this study, 25 selfed (S1) and 25 open-pollinated (OP) progenies of smooth bromegrass created in 2012 were evaluated in the field under normal and recurrent drought stress during 2013–2016. After the first harvest of above-ground biomass in 2016, irrigation was withheld in both environments for 2 months; plants were subsequently re-watered and evaluated. Recurrent drought stress changed the relationships between different traits. Moreover, prolonged drought stress resulted in increased plant productivity (recovery aerial biomass; RABI) of S1 and OP populations in recurrent drought stress compared with normal environment. Mandatory selfing increased persistence of smooth bromegrass genotypes but did not affect recovery after prolonged drought stress. Results revealed that, selecting among S1 families would be more effective than OP ones.  相似文献   
4.
使用高免蛋黄抗体液的利弊及前景   总被引:2,自引:0,他引:2  
张家峥  施萍  牛桂玲 《中国家禽》2003,25(23):45-45
1当前高免蛋黄抗体的应用 产蛋母鸡经用特定的抗原反复数次免疫后,体内可产生较高滴度的特异性抗体,并同时储存于卵黄中,其有效成分即称蛋黄抗体或蛋黄免疫球蛋白(IgY),可以预防和治疗相对应的疾病.对鸡最常用于传染性法氏囊病,在此病的发病早期应用效果较明显,尤其对变异株或不同亚型等株引起的发病,如能从当地发病鸡采集法氏囊制成囊组织灭活疫苗,用这种疫苗经数次免疫的鸡所产的鸡蛋,制成的蛋黄抗体液,用于防治当地的鸡法氏囊病,可以取得良好的效果.蛋黄抗体液还具有成本低,制作工艺简单的优势,在对鸡新城疫、禽流感、鸡传染性喉气管炎等病的防治时也有应用.  相似文献   
5.
Assessments of the behavior of ridden horses form the basis of performance evaluation. The purpose of any performance being evaluated will determine the factors considered important, factors indicative of “poor” performance, and what makes a successful equine athlete. Currently, there is no consistent objective means of assessing ridden horse behavior, and inevitably, given the different equestrian disciplines, the likelihood of a universal standard of good and bad performance is remote. Nevertheless, to protect the welfare of the ridden horse regardless of its specific role, we should strive for consensus on an objective means of identifying behavioral signs indicative of mental state. Current technological developments enable objective evaluation of movement patterns, but many aspects of the assessment of ridden behavior still rely on subjective judgment. The development of a list of behaviors exhibited by ridden horses, a ridden horse ethogram, will facilitate recording of observable behavioral events. However, without objective evidence of the relevance of these behavioral events, such a resource has limited value. The aim of this review was to investigate potential sources of such evidence and relate these to the assessment of ridden horse behavior. The current and potential contribution that further objective measures can make in this process is evaluated. We believe that the only way to improve the welfare of the ridden horse is by objectively identifying behavioral signs that indicate that the horse is either comfortable or uncomfortable with the activity in which it is participating. After there is clear evidence to support this, appropriate adaptation of performance criteria in all disciplines can proceed along with alignment in training systems that ensures a mutually positive experience for both horse and human partners.  相似文献   
6.
Soil particle deposition and/or chemical precipitation can reduce the permeability of drain envelopes and filters. The first step in recognizing clogging phenomena is the identification of the nature of the precipitating materials. Calcium carbonate is a substance of low solubility that precipitates rapidly, forming a hard pan layer in the soil and/or clogging drain envelopes. The main objective of the present study is to investigate the precipitation risk of calcium carbonate in agricultural drain envelopes in the Khuzestan province of Iran. In this study, three indicators namely Ryznar, Langelier and Stiff-Davis indices were employed to assess the precipitation risk of calcium carbonate in agricultural drainage water. Results showed that all agricultural drainage systems in the study area give evidence of a potential risk of calcium carbonate precipitation, but the severity of the problem is different. The results also showed that the Ryznar and Stiff-Davis indices provide a better estimation of the potential precipitation risk of calcium carbonate than the Langelier index. Analyses of soil samples and drain envelopes from a drainage system, installed in the Abadan palm grove, showed that the main chemical component was calcium carbonate.  相似文献   
7.
Information regarding 7 dogs and 1 cat with a spinal arachnoid cyst is presented. All patients were evaluated with survey radiographs and myelography. Computed tomography (CT) following myelography, magnetic resonance (MR) imaging, and sonography, were used in some of the patients. These imaging techniques were evaluated to determine their efficacy in diagnosing arachnoid cysts, ascertaining the extent and internal cyst architecture and detecting associated spinal cord abnormalities. Survey radiographs were nondiagnostic in all patients. Myelographically, the arachnoid cyst was visible in all patients, with partial blockage to flow of contrast medium. CT provided additional information on localization and lateralization of the cyst, and allowed measurement of the degree of spinal cord compression. MR imaging enabled identification of an associated syringomyelia. Sonography was useful for defining the cyst wall and characterizing the internal architecture of the cyst cavity and adjacent spinal cord. Measurements of the degree of spinal cord compression could be made and were similar to measurements made from CT. Additionally, sonography was considered a useful technique for orientating the surgeon to the location and extent of the cyst. In the absence of the availability of CT or MR imaging for evaluating patients with an arachnoid cyst, sonography is considered a valuable technique for directly assessing the spinal cord for associated disease. Decompressive surgery was performed on 4 dogs and 1 cat, all with successful outcomes.  相似文献   
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