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111.
112.

Background

Currently, there is growing interest in developing ante and post mortem meat inspection (MI) to incorporate measures of pig health and welfare for use as a diagnostic tool on pig farms. However, the success of the development of the MI process requires stakeholder engagement with the process. Knowledge gaps and issues of trust can undermine the effective exchange and utilisation of information across the supply chain. A social science research methodology was employed to establish stakeholder perspectives towards the development of MI to include measures of pig health and welfare. In this paper the findings of semi-structured telephone interviews with 18 pig producers from the Republic of Ireland and Northern Ireland are presented.

Results

Producers recognised the benefit of the utilisation of MI data as a health and welfare diagnostic tool. This acknowledgment, however, was undermined for some by dissatisfaction with the current system of MI information feedback, by trust and fairness concerns, and by concerns regarding the extent to which data would be used in the producers’ interests. Tolerance of certain animal welfare issues may also have a negative impact on how producers viewed the potential of MI data. The private veterinary practitioner was viewed as playing a vital role in assisting them with the interpretation of MI data for herd health planning.

Conclusions

The development of positive relationships based on trust, commitment and satisfaction across the supply chain may help build a positive environment for the effective utilisation of MI data in improving pig health and welfare. The utilisation of MI as a diagnostic tool would benefit from the development of a communication strategy aimed at building positive relationships between stakeholders in the pig industry.
  相似文献   
113.
Potatoes (Solanum tuberosum) in Wisconsin are predominately grown on soils that have a high potential for agrichemical leaching. Weed control strategies are not designed for season long control from a single high rate herbicide application but for reduced rates combined with mechanical and cultural strategies. The current recommended herbicide rates provide 7–9 weeks of efficacy. Mechanical measures provide effective early season control, but development of crop canopy prevents cultivation after about four weeks. Past studies have shown that shade levels comparable to those in a potato canopy can significantly reduce weed biomass. This study was initiated to develop a canopy development model and evaluate the difference between Superior and Russet Burbank potatoes. Plots were established in 1988–1992 at the Hancock Agricultural Research Station on Plainfield loamy sand (mixed, typic Upsidaments). Light readings were taken both under the crop canopy and in full sunlight to determine the amount of shading provided by the crop. Physiological Degree Days (P-days) were used to monitor the development of the potato varieties. Regression analysis was used to determine if P-days could be used as a predictor for canopy development. Superior reached maximum canopy (88% shade) at seven weeks after emergence (WAE) and maintained it until 9 WAE. Russet Burbank reaches maximum canopy at 8 WAE (98% shade) and maintains shading above 80% until 13 WAE. The canopy model is an empirical relationship estimated using regression techniques, and is currently being utilized in a weed management module for the WISDOM © software program.  相似文献   
114.
对仔猪腹泻病进行了摸索、研究和总结,根据不同日龄和不同临床表现进行鉴别诊断,同时可采取组织病理学、微生物学方法进一步确诊,并采取针对性防治措施,才能有效地控制仔猪腹泻病.  相似文献   
115.
The DM production from INRA 200, an early maturing hybrid maize grown for silage, was 10±6 and 14 5 t/ha in mid-October 1972 and 1973 (4±2 and 5±8 tons/ac). The plant population in both years was approximately 112,000/ha (45,320/ac). Whole-crop and cob DM percentages were 18±2 and 21±3 for 1972 and 39±9 and 53±0 for 1973, respectively. The cob yields were 49 and 10±4 t/ha (2±0 and 4±1 tons/ac) in 1972 and 1973 and cob in the two years accounted for 46 and 72% of total yield. At harvest the 1973 crop was 4–6 weeks more mature than the 1972 crop. These differences were attributed to the difference in accumulated temperature recorded from May till October, which was 567°C days in 1972 and 817 in 1973. Whole-crop DM content, yield of cob and yield of cob as a percentage of total yield were studied against seasonal temperature accumulation. In the case of DM percentage there was a highly significant linear regression which showed that 627°C days were needed to mature maize to 24% DM content.  相似文献   
116.
Most resettlement in the Pacific, whether for political, economic or environmental reasons, has been in some respects unsuccessful, often resulting in land disputes, social conflicts, marginalisation, impoverishment and return migration. Resettlement after volcanic eruption poses particular problems because of necessary immediacy, temporal uncertainty over the duration of the displacement and the wish of most of those displaced to return, when possible. The eruption of the Manam Island volcano in 2004–2005 displaced over 9000 people to the nearby mainland. Successful resettlement, one of the largest necessitated in the Pacific region, has proved difficult, resulting in land disputes, violence, disease and inertia, as a consequence of 10 years of government inability to achieve a permanent resettlement plan or enact a plan. Despite formal opposition, and intermittent volcanicity, many Manams have chosen to return to the island. The Manam Islanders' experience provides a warning about the complex challenges inherent in population resettlement in only subtly different cultural, geographical and political contexts.  相似文献   
117.
Chronic diseases characterized by bone and cartilage loss are associated with a reduced ability of progenitor cells to regenerate new tissues in an inflammatory environment. A promising strategy to treat such diseases is based on tissue repair mediated by human mesenchymal stem cells (hMSCs), but therapeutic outcomes are hindered by the absence of small molecules to efficiently modulate cell behaviour. Here, we applied a high-throughput drug screening technology to bioprospect a large library of extracts from Irish deep-sea organisms to induce hMSC differentiation toward musculoskeletal lineages and reduce inflammation of activated macrophages. The library included extracts from deep-sea corals, sponges and filamentous fungi representing a novel source of compounds for the targeted bioactivity. A validated hit rate of 3.4% was recorded from the invertebrate library, with cold water sea pens (octocoral order Pennatulacea), such as Kophobelemnon sp. and Anthoptilum sp., showing the most promising results in influencing stem cell differentiation toward osteogenic and chondrogenic lineages. Extracts obtained from deep-sea fungi showed no effects on stem cell differentiation, but a 6.8% hit rate in reducing the inflammation of activated macrophages. Our results demonstrate the potential of deep-sea organisms to synthetize pro-differentiation and immunomodulatory compounds that may represent potential drug development candidates to treat chronic musculoskeletal diseases.  相似文献   
118.
AIM: To validate the use of para-aminohippuric acid (PAH) as a marker for measuring blood flow in wethers consuming a mixed diet of locoweed and blue grama hay.

METHODS: Fourteen sheep, stratified by bodyweight (BW), were assigned to one of three treatments: 0.8 mg swainsonine (SW)/kg BW (HI), 0.2 mg SW/kg BW (LO), and no SW (Control). Sheep were fed various ratios of locoweed and blue grama hay to deliver SW treatments, for 28 days prior to infusion of PAH. Concentrations of SW and activities of alkaline phosphatase (Alk-P) and aspartate aminotransferase (AST) in serum were measured to confirm exposure to SW and subclinical intoxication. A single 20-ml injection of 5% PAH was delivered into the jugular vein after subclinical intoxication had been achieved. Blood samples were collected and serum analysed for PAH immediately prior to injection, then every 5 min from 5–30 min, and every 10 min from 30–60 min, following injection of PAH.

RESULTS: Effective delivery of SW was evident from the greater concentrations of SW measured in the serum of HI compared with LO animals (p<0.05). No significant differences were detected in the rate of elimination (range 0.097–0.108 L/min), elimination half-life (range 6.62–7.24 min), apparent volume of distribution for the central compartment (range 7.14–9.72 L), and clearance (range 0.73–0.92 L/min) of PAH, between treatments.

CONCLUSIONS: Subclinical intoxication with SW did not affect the pharmacokinetics of PAH. Thus, use of downstream dilution of PAH is a valid method to determine the rate of blood flow in nutrient flux experiments that involve consumption of locoweed.  相似文献   
119.
Objective To observe the effect upon the foetus of experimental infection of pregnant cattle with Leptospira borg-petersenii serovar hardjo .
Design A disease transmission study using pregnant cattle.
Procedure Fourteen heifers serologically negative to L hardjo were artificially inseminated and later challenged with a north-Queensland isolate of L hardjo by conjunctival inoculation. The heifers were serologically monitored and their urine examined for the presence of leptospires using culture and fluorescent-antibody tests at appropriate intervals. Elective caesarean sections were performed on pregnant heifers at 6.5 weeks after the challenge. Foetuses were examined using serological, histopathological, microbiological and fluorescent-antibody tests.
Results Ten of the heifers became pregnant, but three subsequently aborted before challenge. After challenge, all 14 heifers seroconverted and L hardjo was isolated from the urine of 6 of the 7 pregnant heifers. No evidence of foetal L hardjo infection was detected. Two of the foetuses had histopatho-logical lesions consistent with Neospora s p infection.
Conclusion It is likely that the isolate of L hardjo used in this study does not normally infect the foetus. Neospora s p may be a more significant cause of bovine reproductive wastage.  相似文献   
120.
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