Transfer feed/milk

Thomas, G. O., A. J. Sweetman, R. Lohmann, and K. C. Jones, Derivation and field testing of air-milk and feed-milk transfer factors for PCBs , Environ. Sci. Technol., 32, 3522-3528 (1998a). 

Investigations concerned with variations in the oxidative stability of milk as a result of feeding practices have centered on the transfer to milk of natural antioxidants. Although Kanno et al. (1968) have reported the presence of 7-tocopherol, the only known natural antioxidant of consequence is a-tocopherol. 

If there is fallout from nuclear weapons tests, or from reactor accidents, milk is likely to be the predominant source of 90Sr in diet, and an important source of 137Cs. A few days will intervene between an episode of fallout and the peak concentration in milk, giving time for preventative measures. It is therefore important to know the transfer factors, so that the future levels in milk can be predicted from the amount of fallout. The transfer depends on the retention of the fallout on the foliage, the amount of herbage eaten by the cattle, and the fraction of the cow s daily intake secreted per litre of milk. The transfer factor feed/milk is defined... 

Only about 2% of ingested a-tocopherol is actually transferred to the milk (King et al., 1966 Dunkley et al., 1968b Schingoethe et al., 1979). Consequently, the economics of direct supplementation of feed with a-tocopherol are unfavourable (Bruhn et al., 1976). If protected supplements are fed, however, the potential for transfer to milk is much greater. Goering et al. (1976) fed protected safflower supplement to cows and reported a 200% increase in the a-tocopherol content of the milk. Control of oxidized flavor by direct addition of emulsified a-tocopherol to milk can be achieved with only 1% of the amount required by ration supplementation (Weihrauch, 1988). 

The transfer to milk of risperidone and its active metabolite 9-hydroxyrisperidone has been examined in two breast-feeding women and in one woman with risperidone-induced galactorrhea (209). The milkrplasma concentration ratio was under 0.5 for both compounds the calculated relative infant doses were 2.3%, 2.8%, and 4.7% of that of women s weight-adjusted doses neither compound was detected in the plasma of the two babies, who achieved their developmental milestones satisfactorily and did not have any adverse effect attributable to risperidone. The authors concluded that maternal risperidone therapy is unlikely to pose a significant hazard to the breast-fed infant in the short term, and recommended an individual benefit-harm analysis to take decisions about this issue. 

Lithium can cause hypotonicity and cyanosis in the neonate, usually termed the floppy baby syndrome. Most data indicate normal neurobehavioral development once these symptoms resolve. Lithium is readily transferred via breast milk. Breast-feeding is not advised for patients who are taking lithium.30... 

American Academy of Pediatrics Committee on Drugs. The transfer of drugs and other chemicals into breast milk. Pediatrics. 2001 108(3) 776-789. (Lists drugs that are considered "compatible with breast-feeding" list is periodically updated.)... 

Bio-transfer module Calculation of the transfer of contaminants to vegetable products (vegetables, cereals, animal feed) and animal products (meat, milk dairy products, poultry, eggs). 

Vreman, K., N.G. van der Veen, E.J. van der Molen, and W.G. de Ruig. 1986. Transfer of cadmium, lead, mercury and arsenic from feed into milk and various tissues of dairy cows chemical and pathological data. Neth. Jour. Agric. Sci. 34 129-144. 

The innate system is of special importance during early infancy. Prior to birth and for at least 4-12 months after birth a child s immune system is poorly developed. It may not become fully competent until age 5.34 35 During the prenatal period maternal antibodies are transferred to the child. IgG crosses the placenta and enters the fetal circulation. Breast milk provides IgA, which remains largely in the child s gut, as well as other protective proteins. UNICEF and the World Health Organization recommend breast-feeding to two years or beyond 34... 

Transfer coefficients can also be deduced from statistics of the levels of 90Sr and 137Cs in milk measured during monitoring of the fallout from nuclear weapon tests. This has the advantage over experimental work of taking into account variations in agricultural practices, but introduces complications such as the use of root crops and imported feed for cattle and the uptake by crops from the soil of activity deposited in previous years. UNSCEAR (1977) analysed data from a number of countries, obtained in the years 1958-74, in the form,... 

Van den Hoek, J., Kirchmann, R.J., Colard, J. Sprietsma, J.E. (1969) Importance of some methods of pasture feeding, of pasture type and of seasonal factors on85 Sr and 134Cs transfer from grass to milk. Health Physics, 17, 691-700. 

The transfer factor Fm from feed to milk is defined in equation (2.11) as the activity per litre expressed as a fraction of the activity ingested daily by the cow. Numerous measurements of Fm have been made by dosing cows with iodine isotopes or by comparing radioactive or stable iodine in milk and in the herbage eaten by the cows. Table 3.6 shows a selection of the results. Fm depends on the yield of milk and on seasonal factors (Gamer, 1971), but it does not appear to depend on the chemical form of the iodine (Bretthauer et al., 1972). Gamer (1971) recommended Fm = 5 x 10 3 d l-1 for UK conditions, but noted that US results tended towards a higher value. 

Table 3.6. Transfer factor of iodine from feed to milk of cattle...

Knapp also sought to deduce the maximum concentration C/(max) of 131I in milk resulting from the fallout, using records of tests in the 1960s where gamma dose and C/ were both measured, Garner s (1960) data on transfer from cattle feed to milk, and Booker s (1958) measurements after the Windscale accident. 

Transfer coefficients of 0.0002 (kg-day)"1 for uptake into milk and 0.0015 (kg-day) 1 for uptake into beef tissue have been reported (Baes et al. 1984). The transfer coefficients represent the fraction of daily aluminum intake in feed that is transferred to a kilogram of milk or beef muscle. Based upon the above values, aluminum is not transferred to beef muscle or milk from feed to any appreciable extent and therefore would not be expected to bioaccumulate in terrestrial food chains. 

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