Paratuberculosis, a chronic disease affecting ruminant livestock, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It has direct and indirect economic costs, impacts animal welfare and arouses public health concerns. In a survey of 48 countries we found paratuberculosis to be very common in livestock. In about half the countries more than 20% of herds and flocks were infected with MAP. Most countries had large ruminant populations (millions), several types of farmed ruminants, multiple husbandry systems and tens of thousands of individual farms, creating challenges for disease control. In addition, numerous species of free-living wildlife were infected. Paratuberculosis was notifiable in most countries, but formal control programs were present in only 22 countries. Generally, these were the more highly developed countries with advanced veterinary services. Of the countries without a formal control program for paratuberculosis, 76% were in South and Central America, Asia and Africa while 20% were in Europe. Control programs were justified most commonly on animal health grounds, but protecting market access and public health were other factors. Prevalence reduction was the major objective in most countries, but Norway and Sweden aimed to eradicate the disease, so surveillance and response were their major objectives. Government funding was involved in about two thirds of countries, but operations tended to be funded by farmers and their organizations and not by government alone. The majority of countries (60%) had voluntary control programs. Generally, programs were supported by incentives for joining, financial compensation and/or penalties for non-participation. Performance indicators, structure, leadership, practices and tools used in control programs are also presented. Securing funding for long-term control activities was a widespread problem. Control programs were reported to be successful in 16 (73%) of the 22 countries. Recommendations are made for future control programs, including a primary goal of establishing an international code for paratuberculosis, leading to universal acknowledgment of the principles and methods of control in relation to endemic and transboundary disease. An holistic approach across all ruminant livestock industries and long-term commitment is required for control of paratuberculosis. Electronic supplementary material The online version of this article (10.1186/s12917-019-1943-4) contains supplementary material, which is available to authorized users.

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The present paper looks at the dimensional errors resulting from tool deflection in the high-speed milling of hardened steel surfaces. These errors are measured as the difference between the theoretical surface and the high-speed milling machined using ball-end mills.The effect of various factors on this dimensional error is investigated. First, account was taken of the workpiece material and the slope of surfaces; the values chosen were those normally used in injection mould manufacturing. The workpiece materials were of 30 and 50 HRC hardness, with slopes of 15 • , 30 • , and 45 • . In this manner, results may thus be of utility to the mould and die industry. The selected tools were solid ball end mills of sintered tungsten carbide, coated with TiAIN. These were of various diameters and lengths, and accordingly exhibited various degrees of slenderness. A great value for this latter parameter is a restraint on the potential application of the high-speed milling technique. This is the main reason for this work.Tests were carried out using three machining strategies, namely, upward, downward, and z-level (horizontal), as well as with two cutting types, downmilling (also called climb milling) and upmilling (or conventional milling). In all cases the resulting roughness was also measured. Dimensional errors in several flat slope planes were measured, comparing with those obtained by simulation.The results of these tests have been applied to the prediction of error in the high-speed milling of two industrial parts. Knowledge of error magnitude may be useful when NC programs are prepared for the machining of mould complex surfaces, since it may then be attempted to enhance accuracy.Reference is made to various practical problems that were necessary to resolve in order to achieve measurement errors less than 20 µm in a process as complex as that of high-speed milling in three axes machining centres.

Forming tools manufacturers have extensively incorporated high-speed milling technology for the finishing of large punch or die tools. The main objective is to achieve a good surface quality directly form machining, without any additional, tedious, manual work. Currently, new advanced high-strength steels (AHSS) are being used for car body parts. In this case, there are two special changes related to the forming tools: a higher proportion of harder surfaces on the working area, and long try-out iterations, due to their great springback. Tempered surfaces and insert blocks harder than 60 HRC are needed to withstand the forming charges with a good working life expectancy. From this, two problems arise with regards to highspeed finishing: first, the deflection of the tool due to the cutting forces, which can produce unacceptable dimensional errors; and second, in the same finishing operation, zones with sharp changes in hardness must be machined with the same CNC program and cutting tool.The key to solving both problems will be the use of newly developed utilities in the preparation stage, and the elaboration of CNC programs using CAM software. In the first case, the deflection of tool is dealt with by a milling model which obtains the values of cutting forces. This model characterises the couple tool/material with six coefficients, which are previously obtained for ball-end milling tools and base die materials. Inputs provided by the CAM user include feed per tooth, and radial and axial depths of cut. The problem of surfaces with areas of different hardness and poorly defined boundaries is solved with a special postprocessor coded in C language. Once the CAM user has defined (on the CAD model) the theoretical boundaries of the tempered areas, the insert blocks or the deposition material areas, this utility includes changes of the programmed feed function in the CNC program.In this paper, these approaches are applied to medium size workpieces with the same features of the actual punch and die for AHSS forming. Results are provided to die manufacturers for application in real forming tools. This technological model of the milling process estimates values of cutting forces and offers manufacturers a reduction of production and lead times.