Human milk system

There are reports that the use of robotic milking systems will significantly reduce mastitis, linked at least partially to the machines more efficient teat disinfection compared to human operators. However, the more frequent visit to be milked and more gentle application and removal of milking equipment from the teats may also contribute to reduced mastitis incidence. On the other hand, the absence of human operators in robotically milked herds may lead to late detection and treatment of mastitis. However, this may be overcome by the introduction of conductivity detection systems which allow early signs of mastitis to be detected (Hogeveen and Meijering, 2000). 

Lactation It is not known whether treprostinil is excreted in human milk or absorbed systemically after ingestion. 

Human milk is a s)mergistic package of essential nutrients and bioactive components. Epidemiological studies have demonstrated that consumption is associated with health benefits for many immune-related conditions (Table 2.1). Breast milk contains the nutrients necessary to support the development of the infant s immune system as well as other components that defend against infection. This includes various antimicrobial substances, factors that promote immime development, constituents that promote tolerance and the priming of the infant immime system, as well as anti-inflammatory components. The purpose of this chapter is to discuss the evidence for the immune benefits of human milk. 

Cytokines are multifunctional glycoproteins involved in cell communication and immune system activation (Ustundag et ah, 2005). Human milk contains an array of cytokines, some in concentrations that could potentially influence immune function. This list includes IL-1(3 (Grosvenor et ah, 1993b Hawkes et ah, 2002c Ustundag et ah, 2005), IL-2 (Bryan et ah, 2006 ... 

Goldman, A. S. (1993). The immune system of human milk Antimicrobial, antiinflainmatory and immunomodulating properties. Pediatr. Infect. Dis. ]. 12, 664-671. 

Most POPs are readily absorbed (via the digestive system and inhalation) and accumulate in fatty tissue, including brain and adipose tissue and human milk. These substances can induce neurological effects and cause altered functioning of the nervous system as well as acting as endocrine disruptors. 

Gas chromatography-low resolution mass spectrometry was used to determine if TCDD is in the samples (12). The GC column used was a 6 ft. x 2 mm i.d. glass 2.5% BMBT liquid crystal on 100/120 mesh Chromosorb WHP (Altech Assoc.) at 225°C. In Figure 3 is shown the output from a standard and typical human milk extract run on an LKB-9000 with a SI-150 (System Industries) data system equipped with a computer controlled multiple ion detector (Ledland, Inc.). The entire extract was... 

Iodine and Se speciation in breast milk provides an example of the use of CE in hyphenated systems with ICP-MS detection. By employing CE, Michalke and colleagues determined selenoaminocids and identified two chemical forms of iodine, I- and thyroxine, which were present in comparable amounts in milk [115-117]. Other authors used SEC and IEC for I speciation in various types of milk and infant formulae (see Table 8.3) and found I- as the main species, with the exception of breast milk and formulae. The latter were found to contain less I than commercial and human milk, and mostly as an unidentified macromolecular compound. 

Lipids As the capacity of the stomach of newborns is very limited, lipids and fat are necessary to provide the large amounts of energy required by the newborn s high body growth rate. Milk fat is the major source of lipid that mammalian newborns use for accumulating body adipose tissue and for the development of their nervous system. The major lipids in milk fat are triglycerides, which represent more than 98 percent of the neutral lipids. From a quantitative point of view, there is no difference in the fat content in cow s (3.8 percent) and human milk (3.7 percent), but they do differ in their qualitative composition in fact, in cow s milk the predominant fatty acids are saturated acids, while polyunsaturated acids are the main fatty acids in human milk, as shown in Table 13.3. 

The most frequent, reliable approach for element speciation in real samples today uses combined - or hyphenated - techniques, where species are selectively separated (e.g., by a chromatographic technique) and then the elements in the various chemical forms are selectively detected. To enhance the quality of measurements, molecule-selective detection is also coupled to separation devices. These combinations provide extended flexibility and broad applicability. Disadvantages are that, as complexity increases, the risk increases of system failure. Besides, species equilibrium can be drastically altered during separation due to dilution, some components can be removed, and so on. Under such conditions, species transformation and destruction is a likely consequence. Therefore, the total separation time should be shorter than the transformation rate of species. Figure 17.1 gives an overview of the strategy and various speciation methods mostly used for element speciation in human milk. 

Vitamin E is widespread in foods and is stored in the body so that deficiency states are very rare. A possible exception may be premature infants with very low fat stores. The concentration of a-tocopherol in cows milk ranges from 3.0 to 5.0 mg/L and is present at about the same level in human milk. While vitamin E has been shown to be essential for normal fertility in rats and other animals, it has never been proven to be necessary for human fertility. However, in recent years there has been renewed interest in the antioxidant function of vitamin E [e.g., in protecting the cardiovascular system (Sytkowski et al., 1990 Gurr, 1994)]. 

There were several new developments during the 1970s. Of particular importance was the purification and characterization of a lipoprotein lipase (LPL) and the acceptance of the postulate that this was the major, if not the only, lipase in cows milk (Olivecrona, 1980). Similarly, the elucidation of the lipase system in human milk as consisting of an LPL and a bile salt-stimulated lipase, and the possible role of the latter in infant nutrition, were noteworthy (Fredrikzon et al, 1978). Also, microbial lipolysis assumed substantial significance with the widespread use of low-temperature storage of raw milk and the recognition that heat-stable lipases produced by psychrotrophic bacteria were a major cause of flavor problems in stored dairy products (Law, 1979). 

Infant formulas are supplemented with Mn and other trace elements in the form of inorganic salts. Whether these supplemented minerals have different bioavailabilities from their counterparts found naturally in human milk or bovine milk has not been extensively investigated. Chan and associates previously reported that Mn was bound to different molecules in human milk, bovine milk and infant formula (12). Inadequate or excessive intake of Mn has severe effects especially during infancy (1,13). It is therefore important to evaluate the bioavailability of Mn in different milk diets. To achieve this aim, suckling rats and everted intestinal sacs derived from these animals were used as systems to study the absorption of Mn from rat milk, human milk, bovine milk and infant formula. Effect of age on Mn absorption in suckling rat pups from various milk diets was also investigated. Some of the data presented in this article have been reported previously (14-17). 

---