Rat milk

In order to determine whether there was sufficient DDT in the milk to produce effects in rats, milk from the cows was separated and the cream was incorporated into a synthetic diet which was fed to a group of rats for a period of 4 months. Butter was churned from some of the cream and this was likewise incorporated into a diet and was fed to another group of rats. These data will be published elsewhere. 

P. J., Interactions between dmetidine, nitrofurantoin, and probenecid active transport into rat milk, J. Pharmacol. Exp. Ther. 2001, 296, 175-180. 

Lactation Zileuton and its metabolites are excreted in rat milk. It is not known if... 

Lactation Sumatriptan and eletriptan are excreted in breast milk. Zolmitriptan, naratriptan, almotriptan, frovatriptan, and rizatriptan are excreted in rat milk. Children Safety and efficacy in children have not been established. 5-HT- receptor... 

Dostal LA, Hopfer SM, Lin SM, et al. 1989. Effects of nickel chloride on lactating rats and their suckling pups, and the transfer of nickel through rat milk. Toxicol Appl Pharmacol 101 220-231. 

A. Preiss, J. Kruppa, J. Buschmann, C. Mugge, The determination of trifluoroacetic acid in rat milk samples by F-19-NMR spectroscopy and capillary gas chromatography, J. Pharm. Biomed. Anal. 16 (1998) 1381-1385. 

Dostal, L.A., Weaver, R.P. Schwetz, B.A. (1987a) Transfer of di(2-ethylhexyl) phthalate throngh rat milk and effects on milk composition and the mammary gland. Toxicol, appl. Pharmacol., 91, 315-325... 

Monis, B., Rovasio, R. A. and Valentich, M. A. 1975. Ultrastructural characterization by ruthenium red of the surface of the fat globule membrane of human and rat milk with data on carbohydrates of fractions of rat milk. Cell Tiss. Res. 157, 17-24. 

LPL activity in rats milk is only about 0.2% of that of guinea pigs milk, probably reflecting interspecial differences in milk secretory processes (Hamosh and Scow, 1971). Activity in dogs and cats milk is also low, of a similar order to human milk (Freed et al., 1986). 

Hamosh, M., Scow, R.O. 1971. Lipoprotein lipase activity in guinea pig and rat milk. Biochim. 

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). 

Milk. Human breast milk was obtained from volunteers and fresh raw bovine milk was obtained from local farms. Raw milk was used instead of pasteurized milk in order to preserve the Mn binding ligands in their natural form. The infant formula used was regular Similac (Ross Laboratories). Fresh rat milk was obtained from lactating female rats 8-12 days after parturition as described previously (17). 

Human milk contained relatively less Mn when compared to the other milk diets examined. The endogenous Mn concentrations of human milk, bovine milk, infant formula and rat milk used in the present studies as determined by flameless atomic absorption spectrophotometry were 8 + 3, 30 + 5, 73 + 4, 148 + 18 pg/liter respectively. It is possible that the higher concentrations of endogenous Mn in infant formula and rat milk might compete with the added 5 Mn for transport during the experiments. However, the addition of non-... 

Human colostrum (1-5 days) human milk (over 30 days) Rat milk (Day 1) Rat milk (Day 25)... 

Rat mammary-gland transferrin. Rat milk transferrin contains four glycovari-ants that differ only in their sialic acid content. The primary structure of the two major variants has been determined by Escriva et al. [67]. As shown in Fig. 8D, the glycoforms contain either one or two A-acetylneuraminic acid residues a-2,6-linked to galactose in a conventional diantennary glycan of the A-acetyllactosaminic type. Most contain fucose a-l,6-linked to the proximal A-acetylglucosamine residue. 

Palminger I and Oskarsson A (1991) Transfer of lead via rat milk and tissue uptake in the suckling offspring. In Aitio A, Aro A, Jarvisalo J and Vainio H, eds. Trace elements in Health and Disease, pp. 109-115. The Royal Sodety of Chemistry, London, UK. 

In serum, absorbed vanadium is transported mainly bound to transferrin (Lager-kvist etal. 1986, Kustin and Robinson 1995). Vanadium in rat milk was found mainly in the protein fraction, and perhaps also in lactoferrin (Sabbioni and Rade 1980), in which form it is transferred from the mother to the pups. In older rats, vanadium appears to be converted into vanadyl-transferrin and ferritin complexes in the plasma and body fluids (Edel and Sabbioni 1989, Sabbioni and Marafante 1981). 

Figure 20.2 documents that bromide ions ingested by the dams moved easily into rat milk and were transferred via mother s milk to the suckfing. The amount of bromide in mother s milk depended on the bromide concentration in the drinking water consumed by the dams. 

Table 3.219 Composition of lipids in bovine, human and rat milks (adapted from Morrison, 1970)...

However the rat also has several limitations. Rats normally consume low-fat diets (approximately 5 percent fat), while human infants consume 45 to 55 percent of their calories as fat. Therefore the rat is a poor model for assessing the effects of altering or supplementing fats (including LC-PUFAs). Studies of LC-PUFA supplementation in the developing rat pup involved supplementing the mother and thus emiching the composition of rat milk (Haubner et... 

Liithy J, Heim TH, Schlatter CH (1983) Tiansfia- of [ H] pyrrolizidine alkaloids from Senecio vulgaris L. and metabolites into rat milk and tissues. Toxicol Lett 17 283-288... 

Candrian U, Liithy J, Graf U, Schlatter CH (1984) Mutagenic activity of the pyrrolizidine alkaloids Seneci-phylline and senkirkine in Drosophila and their transfer into rat milk. Food Chem Toxicol 22 223-225... 

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