Concentrations of oestradiol-17β and progesterone in bovine plasma and defatted milk during the post-partum anovulatory period, during oestrous cycles and following ovariectomy

Abeyawardene, S.A.; Hathorn, D. J.; Glencross, R.G.

doi:10.1016/0007-1935(84)90040-x

Cited by 25 publications

(13 citation statements)

References 26 publications

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“…The absolute concentrations of both plasma and milk E 1 and E 2 in our study are low relative to some reports in the literature (Monk et al, 1975;Erb et al, 1977;Patel et al, 1999) but are similar to others (Glencross et al, 1973;Glencross and Abeywardene, 1983;Abeyawardene et al, 1984). The trend for increased plasma E 1 and E 2 concentrations during pregnancy is consistent across studies.…”

supporting

confidence: 81%

“…Our lab reported greater quantities of E 2 in milk from cows 141 to 210 d pregnant compared with cows < 141 d pregnant or nonpregnant cows (Pape-Zambito et al, 2007). Batra et al (1980) and Abeyawardene et al (1984) reported that milk E 2 concentrations were positively correlated with plasma E 2 and suggested that plasma E 2 concentrations were a predictor of milk E 2 concentrations. Other reports have clearly shown an increase in plasma estrogens as pregnancy advances.…”

Section: Introductionmentioning

confidence: 60%

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17β-Estradiol and Estrone Concentrations in Plasma and Milk During Bovine Pregnancy

Pape-Zambito

Magliaro

Kensinger

2008

Journal of Dairy Science

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Estrone (E1) and 17beta-estradiol (E2) are present in milk, but the mechanism(s) that regulate their appearance in milk are not known. The objectives of this study were to determine the impact of stage of pregnancy on the concentrations of E1 and E2 in plasma and milk and to determine the correlations between plasma and milk E1 and E2 and with milk components throughout pregnancy. Blood and milk samples were collected from 13 cows every 28 d throughout pregnancy. The E1 and E2 were quantified in plasma and milk using RIA after organic solvent extractions and Sephadex LH-20 column chromatography. Plasma E1 concentrations averaged 0.8, 16.9, and 41.8 pg/mL in trimesters 1, 2, and 3, respectively. The respective E1 concentrations in milk averaged 0.6, 7.9, and 27.1 pg/mL. The E2 concentrations in plasma averaged 0.5, 0.9, and 2.0 pg/mL; milk E2 averaged 0.3, 0.9, and 5.0 pg/mL. Plasma and milk E2 concentrations were greater in trimester 3 compared with trimesters 1 and 2. The E1 concentrations in milk were significantly correlated with plasma E1 concentrations (r = 0.77), percentage of milk fat (r = 0.50), and milk yield (r = -0.43). The E2 concentrations in milk were significantly correlated with plasma E2 concentrations (r = 0.93), percentage of milk protein (r = 0.63), and milk yield (r = -0.57). The milk-to-plasma ratio of E2 increased from 0.4 during trimester 1 to 2.2 in trimester 3, which suggested that the mechanism(s) regulating the appearance of E2 in milk may change over the course of pregnancy.

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supporting

confidence: 81%

Section: Introductionmentioning

confidence: 60%

17β-Estradiol and Estrone Concentrations in Plasma and Milk During Bovine Pregnancy

Pape-Zambito

Magliaro

Kensinger

2008

Journal of Dairy Science

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“…But as much as 98% of the total estrogens in milk has been reported to be in conjugated non-free forms (Farlow et al 2009) more likely to be associated with the aqueous milk fraction. Therefore, one can assume that the difference in total estrogen bioavailability between whole milk containing fat and whey is less pronounced than suggested by Abeyawardene et al (1984) and that the proliferative effect of whey that we observe reflects relatively well the proliferative effect of whole milk containing fat.…”

Section: Discussionsupporting

confidence: 58%

“…According to Abeyawardene et al (1984) the level of free estradiol is approximately half in skim milk and approximately one fourth in whey compared with whole milk. Thus, when we test the effect of whey, any effect of free estradiol is likely to be up to four times lower than it would have been with whole milk containing milk fat.…”

Section: Discussionmentioning

confidence: 99%

Proliferative effect of whey from cows' milk obtained at two different stages of pregnancy measured in MCF-7 cells

Nielsen

Andersen

Sejrsen

et al. 2011

Journal of Dairy Research

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Dietary estrogens may play a role in the etiology of hormone-dependent cancers like breast cancer. Cow's milk contains various endogenous estrogens and feed derived phytoestrogens that potentially contribute to an estrogenic effect of milk in consumers, and therefore we evaluated the effect of milk (whey) in a proliferation assay with estrogen-sensitive MCF-7 human breast cancer cells. Milk samples were obtained from 22 cows representing different stages of pregnancy (first and second half) and whey was produced from the milk. 0·1, 0·25 or 0·5% whey was included in the cell culture medium and after 6 days of treatment cell proliferation was assessed by a colorimetric method with a fluorometer. Whey induced significant (P<0·05) proliferative effects compared with control cells with no added whey at all concentrations tested. There was no difference in the proliferative effect of whey depending on the stage of pregnancy from which the milk was obtained. We did not observe anti-proliferative effects when whey was tested in the presence of 10 pm estradiol in the medium. In conclusion, these results indicate that whey, irrespective of the pregnancy stage from which the milk was obtained induced a significant proliferative response in MCF-7 cells and no anti-proliferative effect, which may be caused, at least in part, by estrogens present in milk. The implications of our findings in relation to for example breast cancer will have to be studied further in other model systems preferentially in vivo.

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“…Most of the researches were focused on environmental water and sediments. Up to now, several researchers quantified estrogens in skim milk [24][25][26] and whole milk [19,27,28], but few quantified estrogen and progesterone in butter. Actually, 1 kg of milk may produce approximately 3 g of butter.…”

Section: Introductionmentioning

confidence: 99%

Application of multiwall carbon nanotubes-based matrix solid phase dispersion extraction for determination of hormones in butter by gas chromatography mass spectrometry

Wang

et al. 2011

Journal of Chromatography A

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Concentrations of oestradiol-17β and progesterone in bovine plasma and defatted milk during the post-partum anovulatory period, during oestrous cycles and following ovariectomy

Cited by 25 publications

References 26 publications

17β-Estradiol and Estrone Concentrations in Plasma and Milk During Bovine Pregnancy

17β-Estradiol and Estrone Concentrations in Plasma and Milk During Bovine Pregnancy

Proliferative effect of whey from cows' milk obtained at two different stages of pregnancy measured in MCF-7 cells

Application of multiwall carbon nanotubes-based matrix solid phase dispersion extraction for determination of hormones in butter by gas chromatography mass spectrometry

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