Colostrum and milk are rich sources of immunoglobulins. These secretions have developed through evolution to ensure homologous transfer of passive immunity from mother to offspring. The immunoglobulins that are passed from mother to her offspring, whether by transplacental transfer or by ingestion of colostrum and milk, can form an important link between the immunological experience of the mother and the immune capacity of the newborn. This immunological link also includes many immune factors that may be present in mammary secretions other than the immunoglobulins. The immunoglobulins in colostrum and milk also provide opportunities to harness their immunological function for the benefit of other animals, including humans. Research has demonstrated that bovine colostrum and milk, whether or not they are from cows immunized against specific pathogens, provide a medium for the heterologous transfer of passive immunity, and may offer disease protection in a range of species. New technologies for enhancing efficacy of vaccination, enhancing stability and extending shelf-life of the immunoglobulin preparation while minimizing the impact of the processing, and extending the effectiveness of the immunoglobulin in the intestine, may enhance future use of colostrum and milk based on their potent immunological activity. While the mechanisms by which immunoglobulins are transferred from mother to neonate and their role in the neonate have become well documented, additional research is needed to clarify the mechanisms of action of the immunoglobulins derived from milk or colostrum when used in animals that are developmentally more mature.  The crazy-paving pattern: a radiological-pathological correlation The crazy-paving pattern is a linear pattern superimposed on a background of ground-glass opacity, resembling irregularly shaped paving stones. The crazy-paving pattern is initially described as the pathognomonic sign of alveolar proteinosis. Nowadays this pattern is a common finding on high-resolution CT imaging, and can be seen in a number of acute and chronic diseases. The purpose of this paper is to illustrate different diseases that cause this crazy-paving pattern and to correlate the radiological findings from computed tomography with the histopathological findings. The superimposition of a linear pattern on ground-glass opacity on computed tomography images results in a pattern that is termed crazy-paving pattern, resembling the structure of irregularly shaped paving stones [1, 2] . The crazy-paving pattern is a common finding on thin-section computed tomography (HRCT), but also on multidetector computed tomography (MDCT). Ground-glass opacity is defined as a hazy increase in lung density with preservation of airway and vessel margins [3] . Ground-glass opacity occurs when there is a mild decrease in the amount of air in the airspaces and a filling of the airspaces with fluid, cells or other material, thickening of the alveolar walls or thickening of the interstitium. The linear component of this pattern can be caused by a thickening of the interlobular septa (septal lines), a thickening of the intralobular septa and the intralobular interstitium (intralobular reticular pattern and intralobular branching lines) or a linear deposition of material within the airspaces at the borders of the acini (periacinar pattern) ( Fig. 1 ) [4] . The crazypaving pattern was initially described as a pathognomonic sign of alveolar proteinosis; however, nowadays, this pattern has been reported in a variety of acute and chronic diseases as summarised in Table 1 [2, [5] [6] [7] [8] . The purpose of this paper is to illustrate different diseases showing a crazypaving pattern. The diagnosis is made based on clinical or on histological findings. If histopathological proof is available, a radiological-histopathological correlation is made.