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

1982 ◽  
Vol 35 (2) ◽  
pp. 145 ◽  
Author(s):  
Stuart W Green ◽  
Marilyn B Renfree

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.

1980 ◽  
Vol 33 (1) ◽  
pp. 35 ◽  
Author(s):  
B Green ◽  
K Newgrain ◽  
J Merchant

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.


Development ◽  
1981 ◽  
Vol 62 (1) ◽  
pp. 325-338
Author(s):  
Elizabeth J. Thornber ◽  
Marilyn B. Renfree ◽  
Gregory I. Wallace

The in vitro uptake and incorporation of [3H]ui idine by blastocysts of the tammar wallaby showed a 16- and 30-fold increase from day 0 to day 10 after removal of pouch young, respectively. Two of the six non-expanded blastocysts recovered on day 5 showed a tenfold increase in incorporation. During the first ten days after removal of pouch young the diameter of the blastocyst increased threefold. Endometrial exudate from gravid uteri had a higher protein concentration than exudate from nongravid uteri (39·5 ± 0·9 and 32·0 ± 2·0 mg/ml (mean ± s.e.m.), respectively). Endometrial exudates from uteri where the blastocyst was actively growing were found to contain six uterine-specific proteins. These were separated by gradient polyacrylamide gel electrophoresis. Two of the proteins were pre-albumins and the others were larger molecules (M.W. 153000–670000). Two proteins were only present at particular stages of pregnancy: the other four were present at all stages from diapause to birth, in exudate from gravid and nongravid uteri. The specific binding of progesterone and androstenedione to proteins in endometrial exudates or uterine flushings from pregnant wallabies was less than one per cent of the value obtained from day-5 pregnant rabbits. The ability of mouse blastocysts to take up and incorporate [3H]uridine into acidinsoluble material increased threefold in the presence of day-10 endometrial exudates from wallabies. However, this was less than ten percent of the values obtained in the presence of bovine serum albumin. The concentration of calcium in endometrial exudates increased from 23·6 to 45·2 μg/ml during pregnancy; in endometrium it remained at 88·7 μg/g (wet weight) throughout pregnancy, and in plasma it was 53·3 μg/ml. The concentration of zinc in endometrial exudates was 4·5 μg/ml; in endometrium it decreased from 21·8 to 13·3 μg/g (wet weight) during pregnancy and in plasma it was 0·6 μg/ml.


1997 ◽  
Vol 9 (2) ◽  
pp. 243 ◽  
Author(s):  
K. Basden ◽  
D. W. Cooper ◽  
E. M. Deane

A study has been made of the development of four lymphoid tissues from birth to maturity in the tammar wallaby Macropus eugenii —the cervical and thoracic thymus, lymph nodes and gut-associated lymphoid tissue (GALT). The development of these tissues in the tammar wallaby is similar to that in two other marsupials, the quokka Setonix brachyurus and the Virginian opossum Didelphis virginiana. Lymphocytes were first detected in the cervical thymus of the tammar at Day 2 post partum and in the thoracic thymus at Day 6. They were subsequently detected in lymph nodes at Day 4 and in the spleen by Day 12 but were not apparent in the GALT until around Day 90 post partum. By Day 21, the cervical thymus had developed distinct areas of cortex and medulla and Hassall’s corpuscles were apparent. The maturation of other tissues followed with Hassall’s corpuscles in the thoracic thymus by Day 30 and nodules and germinal centres in the lymph nodes by Day 90. Measurement of immunoglobulin G concentrations in the serum of young animals indicated a rise in titre around Day 90 post partum, correlating with the apparent maturation of the lymphoid tissues.


1990 ◽  
Vol 2 (1) ◽  
pp. 79 ◽  
Author(s):  
TP Fletcher ◽  
G Shaw ◽  
MB Renfree

Female tammar wallabies were treated with the dopamine agonist bromocriptine at the end of pregnancy to suppress the peripartum pulse of plasma prolactin. The animals were subsequently observed, and a series of blood samples taken to define the hormonal profiles before and immediately after parturition. Birth was observed in 4/5 control animals and occurred in 8/9 bromocriptine-treated animals. The peripartum peak in plasma PGFM concentrations was not affected by bromocriptine although the pulse of prolactin normally seen at parturition was completely abolished. The timing of luteolysis was apparently unaffected, as plasma progesterone concentrations fell similarly in both treated and control animals immediately after parturition. However, all of the neonates of the bromocriptine-treated animals died within 24 h, possibly because of a failure to establish lactation. Subsequent onset of post-partum oestrus was delayed or absent both in control and in bromocriptine-treated animals, suggesting that the frequent blood sampling and disturbances in the peripartum period interfered with these endocrine processes. It is concluded that both prolactin and prostaglandin can induce luteolysis in the pregnant wallaby, but that the normal sequence of events results from a signal of fetal origin inducing a prostaglandin release from the uterus, which in turn releases a pulse of prolactin that induces a progesterone decline.


1983 ◽  
Vol 96 (1) ◽  
pp. 155-161 ◽  
Author(s):  
C. H. Tyndale-Biscoe ◽  
L. A. Hinds ◽  
C. A. Horn ◽  
G. Jenkin

Concentrations of progesterone, prolactin, LH and 13,14 dihydro-15-keto-prostaglandin F2α (PGFM) were measured in plasma of eight tammar wallabies at 8-hourly intervals during the end of pregnancy and post-partum oestrus initiated by removing the pouch young, and during the end of the oestrous cycle, similarly initiated. In the non-pregnant cycle oestrus occurred 29·7 ± 0·7 (mean ±s.e.m.) days after initiation of the cycle, was preceded by a slow decline in progesterone concentration from 1·6 nmol/l to less than 0·64nmol/l and was followed by a preovulatory peak of LH 5·3± 3·9 h later. In the pregnant cycle birth occurred 26·1±0·2 days after removing the pouch young and was followed 8·0 ± 2·1 h later by oestrus and 16·0± 2·5 h by an LH peak. The latter events thus occurred 3·2 days earlier in the pregnant than in the non-pregnant cycle. Parturition coincided with a very rapid decline in progesterone and a transient high peak of prolactin. In two females sampled less than 25 min after parturition there was a transient peak of PGFM but in all others the concentrations of PGFM remained basal throughout. It is suggested that the fetus and/or placenta is involved in both the premature decline in progesterone and the initiation of parturition and that onset of oestrus and ovulation, being a consequence of a decline in progesterone, are therefore also determined by the fetus.


2004 ◽  
Vol 16 (8) ◽  
pp. 811 ◽  
Author(s):  
Damien B. B. P. Paris ◽  
David A. Taggart ◽  
Monica C. J. Paris ◽  
Peter D. Temple-Smith ◽  
Marilyn B. Renfree

The distribution of spermatozoa and seminal plug in the reproductive tract and the timing of ovulation were examined at various times in a naturally mated monovular macropodid marsupial, namely the tammar wallaby (Macropus eugenii). After the first post partum (p.p.) mating, 28 females were isolated and their reproductive tracts dissected at 0.5, 6, 18, 36 and 40 h post coitum (p.c.). Each tract was ligated into 13 major anatomical sections and spermatozoa and eggs were recovered by flushing. Mating was possibly delayed by handling and occurred 21.7 ± 2.5 h p.p. in these animals. Copulation lasted 7.8 ± 0.7 min. Within 0.5 h after a single mating, the tract contained 25.8 ± 10.2 × 106 spermatozoa and 21.6 ± 8.8 g of seminal plug, 96% and 70% of which was lost within 6 h p.c. respectively. Spermatozoa reached the uterus, isthmus and ampulla of the oviduct on the side of the developing follicle within 0.5, 6 and 18 h p.c., respectively, and a uterine population of 26.1 ± 12.103 spermatozoa was maintained for over 40 h. Sperm numbers were reduced at the cervix (up to 57-fold) and uterotubule junction (eight-fold) and only one in approximately 7500 ejaculated spermatozoa (3.4 ± 0.9 × 103) reached the oviduct on the follicle side. Differential transport of spermatozoa was not observed. Although the numbers of spermatozoa were reduced in the parturient uterus, they were highly variable and were not significantly different to those in the non-parturient uterus. Ovulation and recovery of sperm-covered eggs from the isthmus occurred 36–41 h p.c. (49–72 h p.p.). In contrast with the polyovular dasyurid and didelphid marsupials, the tammar wallaby ejaculates large numbers of spermatozoa, but transport is relatively inefficient and sperm storage in the tract before ovulation is limited.


1970 ◽  
Vol 16 (3) ◽  
pp. 161-165 ◽  
Author(s):  
Richard T O’Kell ◽  
Joseph R Elliott

Abstract Age- and sex-related "normal" values were calculated for data obtained by screening 8015 patients’ sera with the Technicon SMA 12/60 at the time of hospital admission. Calcium, phosphorus, total protein, and albumin concentrations decrease with age; glucose, urea nitrogen, cholesterol, and lactic dehydrogenase concentrations increase. Uric acid concentration increases with age in women. Mean values for calcium, glucose, urea nitrogen, and uric acid concentrations are greater in men. Serum glutamic-oxaloacetic acid transaminase activity is most frequently abnormal, total protein concentration least frequently. Alkaline phosphatase and bilirubin results were unremarkable.


1990 ◽  
Vol 70 (3) ◽  
pp. 811-819 ◽  
Author(s):  
M. LÉONARD ◽  
H. T. HUNG ◽  
G. ROBITAILLE ◽  
E. BLOCK

Twenty-three Holstein cows received one injection of recombinant bovine somatotropin (bST) every 28 d at one of four doses: 0, 320, 640, or 960 mg 28 d−1. All injections started in early lactation and continued until the cows were dried-off. Composites of AM and PM milkings were analyzed for fatty acids by gas-liquid chromatography, for percent milk protein by infrared analysis and for casein by electrophoresis. For the 0, 320, 640, 960 mg cow−1 28 d−1 bST treatment groups, average ± SE milk protein percents for the entire lactation were 3.24 ± 0.08%, 3.25 ± 0.07%, 3.31 ± 0.08% and 3.24 ± 0.07%, respectively (P > 0.05); average milk caseins were 2.59 ± 0.07%, 2.61 ± 0.06%, 2.60 ± 0.07% and 2.57 ± 0.06%, respectively (P > 0.05), and average whey proteins were 0.65 ± 0.03%, 0.64 ± 0.03%, 0.71 ± 0.03% and 0.67 ± 0.03%, respectively (P > 0.05). No effect of bST was observed on milk fatty acids and protein at any dose or stage of lactation. Concentrations of αs-, β- and K-casein were not affected by bST treatment (P > 0.05). Fat percentages were 3.78 ± 0.21%, 3.91 ± 0.19%, 3.76 ± 0.19% and 4.02 ± 0.16% for the 0, 320, 640 and 960 mg 28 d−1 treatment (P > 0.05). Milk fatty acids were not affected by bST treatment (P > 0.05). Short chain fatty acids and medium chain fatty acids were decreased (P < 0.05) with progressing lactation while long chain fatty acids were increased in late lactation (P < 0.05). Key words: Somatotropin, composition of milk, caseins, milk fatty acids


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