We describe a new mechanistic bio-economic model for simulating the spread of Mycobacterium avium ssp. paratuberculosis (MAP) within a dairy cattle herd. The model includes age-dependent susceptibility for infection; age-dependent sensitivity for detection; environmental MAP build-up in five separate areas of the farm; in utero infection; infection via colostrum and waste milk. and it... https://www.houseandholders.shop/product-category/duvet-cover/