Specific Proteins in the Whey From Milk of the Grey Kangaroo

Milk samples were obtained at regular intervals throughout lactation from tammar wallabies (M. eugenii). Total solids represented only 12 % (w/w) of the milk at the commencement of lactation and gradually increased to about 40% at 36 weeks. Milk proteins represented 4% (w/w) of whole milk during the first 18 weeks of lactation, followed by a rapid increase to around 13 % (w/w) at 36 weeks. Sodium and potassium concentrations were high in early samples of milk but declined to minimal values at 30 weeks. The milk was isosmotic to the plasma at all stages.

Section: Discussionmentioning

confidence: 99%

Changes in Milk Composition During Lactation in the Tammar Wallaby (Macropus Eugenii)

Green¹,

Newgrain²,

Merchant³

1980

“…Major quantitative and qualitative changes take place in the composition of marsupial milk during lactation (Gross and Bolliger 1959;Kaldor and Ezekiel 1962;Bailey and Lemon 1966;Jordan and Morgan 1968;Lemon and Poole 1969;Sharman 1970;Griffiths et at. 1972;Renfree et al 1981;Green and Renfree 1982).…”

Section: Introductionmentioning

confidence: 99%

Qualitative and Quantitative Changes in Milk Fat during Lactation in the Tammar Wallaby (Macro pus eugenii)

Green¹,

Griffiths²,

Leckie³

1983

There are major quantitative and qualitative changes in the milk lipids during lactation in the tammar wallaby, Macropus eugenii. The crude lipid content of the milk is relatively low during the first 10 weeks of lactation; between 10 and 26 weeks post partum the lipid content increases gradually but after that it increases rapidly. The triglyceride fraction of the lipid at early stages oflactation contains a large amount of palmitic acid and relatively little oleic acid whereas mature milk exhibits little palmitic and much oleic acid. In the early stages of lactation fat represents 15% of the total solids and carbohydrate 55%; around 26-30 weeks post partum the carbohydrate moiety falls sharply to a level less than 2% of the solids while lipids increase to c. 60% of the solids. These changes coincide with increases in milk solids, emergence of the young from the pouch, ingestion of herbage, and fermentation of cellulose in the stomach.

“…Six marsupial species have been sampled so far: the red kangaroo, M. rufus (Sloan et al 1961;Bailey and Lemon 1966;Lemon and Bailey 1966;Lemon and Barker 1967;Griffiths et al 1972); the opossum, Didelphis virginiana (Sloan et al 1961;Bergman and Housley 1968); the brush-tailed possum, Trichosurus vulpecula (Gross and Bolliger 1959); the grey kangaroo, M. giganteus (Lemon and Poole 1969;Messer and Mossop 1977); the quokka, Setonix brachyurus (Sloan et af. 1961;Kaldor and Ezekiel 1962;Jordan and Morgan 1968;Loh and Kaldor 1973); and the tammar, M. eugenii (Messer and Green 1979;Green et al 1980).…”

Section: Introductionmentioning

confidence: 99%

Changes in the Milk Proteins during Lactation in the Tammar Wallaby, Macropus eugenii

Green¹,

Renfree²

1982

Samples of whey proteins from the milk of tammar wallabies, Macropus eugenii, were examined by acrylamide gel electrophoresis at all stages of lactation up to 280 days post partum. Whey albumin, ,B-globulin and y-globulin fractions had similar electrophoretic mobility to that of the equivalent serum protein fractions, but the proteins in the IX-globulin and pre-albumin regions differed markedly. The IX-globulins are presumed polymorphic because individuals at the same stage of lactation showed great variability in these electrophoretic regions: up to five polymorphic bands were recognized. Milk proteins changed qualitatively throughout lactation, and in particular the concentration of the pre-albumin and IX-globulin fractions increased from approximately day 180 to the end of lactation. Total protein concentration of both whole milk and whey approximately doubled in the second half of lactation compared to the first half, reaching maximum mean values of 114 ± 47 and 96 ± 50 g 1-1 , respectively. Whole milk contained consistently more protein than whey, presumably due to the casein it contains.