Survey of numbers and types of lesions detectable in pig heads and the implications for human and animal health
subclinical sheep scab in bighorn sheep when mite numbers have been very low (Boyce and others 1991). More important, however, is how early in the progression of the disease a diagnosis can be made by serological methods. ELISAs are one of the most frequently used methods for this but there is a wide variation in the time at which ELISA seropositivity occurs, usually coinciding with the onset of clinical signs, an increase in the number of mites and lesion spread. While diagnosis of scab can be made by ELISA as early as seven days after infestation in experimentally infested cattle (Lonneux and others 1998), this does not appear to be the case in sheep in which circulating antibodies detectable by ELISA appear only after about four weeks, coinciding with the onset of the rapid growth phase of the disease (Bates 1997). The present observations would appear to confirm this. In a separate experiment (not reported here), two sheep were experimentally infested with P ovis and serum taken from them at weekly intervals was assayed by immunoblotting and ELISA. The sheep were positive by immunoblotting two and three weeks after infestation whereas they were unequivocally ELISA positive only five and six weeks after infestation (one was just positive after four weeks) (Fig 1). In the serological investigations of the second outbreak on the affected farm, the two methods were compared. The most significant finding was that immunoblotting was superior to ELISA not only in early diagnosis, but also in differential diagnosis of sheep scab in cases where the ELISA results were negative. The reason for this is not clear, but it is worth noting that native antigens were used in ELISA, while denatured antigens were used in immunoblotting.
Assessment of risk for humans associated with Supply Chain Meat Inspection – The Danish Way
The abstract summarizes the report in an adequate way, and brings the reader into the questions addressed as well as summarizes well the conclusions of the report.
Instrumentation and Automated Photometric Titration Procedure for Total Acidity Determination in Red Wine Employing a Multicommuted Flow System
An automated procedure for photometric titration of red wine and associated instrumentation is described. The procedure was based on the flow-batch approach implemented employing multicommutation. The photometric detection was carried out using a homemade LED-based photometer. The mixing device, LED, and photodetector were attached to the titration chamber in order to form a compact and small-sized unit. The flow system comprised an automatic injector and three-way solenoid valves, which were controlled by a microcomputer through an electronic interface card. The software, written in Quick BASIC 4.5, was designed with abilities to accomplish all steps of the titration procedure including data acquisition and real-time processing to decide about the course of titration in the following step and so forth, until the titration endpoint was reached. The usefulness of the proposed titration system was demonstrated by analyzing red wine samples. When results were compared with those obtained using the AOAC reference method, no significant difference was observed at the 95% confidence level. A relative standard deviation of ca  2% (n=9 ) was obtained when processing a typical red wine sample containing 7.3 gl -1 total acidity expressed as tartaric acid.