Maternal-Fetal Utilization of Zinc by Sheep

Hansard, Sam L.; Mohammed, A. S.

doi:10.2527/jas1968.273807x

Cited by 15 publications

(6 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In either instance, it is clear that a hepatic 'store' of Zn of this size would be quickly exhausted if a substantial diminution occurred in the subsequent supply of Zn to the foetus. In the present study, in agreement with Hansard & Mohammed (1968), very high concentrations of Zn were found in the foetal liver early in gestation. A possible explanation for this high level of Zn, which occurs to a large extent as metallothionein (Bremner et al 1977) is that it arises as a response to the greatly increased content of Zn in the early foetal circulation.…”

Section: Discussionsupporting

confidence: 92%

“…A possible explanation for this high level of Zn, which occurs to a large extent as metallothionein (Bremner et al 1977) is that it arises as a response to the greatly increased content of Zn in the early foetal circulation. It is known that metallothionein synthesis in rat liver can be induced by high circulating levels of Zn (Bremner & Davies, 1975) and Hansard & Mohammed (1968) found that, in the 45 d lamb foetus, there was 7.5 mg Zn/kg blood compared with amounts of 3.0 and 2 3 mg/kg at 95 and 140 d.…”

Section: Discussionmentioning

confidence: 99%

“…It is of interest to compare the foetal demands for Cu and Zn in late pregnancy with values for the amounts and availability of these metals in foodstuffs. Hansard & Mohammed (1968) showed that 13 % of the Zn in a feed containing 30 mg/kg was absorbed by pregnant ewes. Suttle & Price (1976) estimated that the 'true availability' of Cu from cut herbage to non-pregnant animals was 0.048.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

The accretion of copper and of zinc by the foetuses of prolific ewes

Williams¹,

McDonald²,

Bremner³

1978

Br J Nutr

View full text Add to dashboard Cite

1. The amounts of copper and zinc in the foetuses of ewes carrying from one to four lambs were measured at different stages of gestation and estimates were made of the amounts of these metals in their livers.2. The accretion of Cu and Zn could be described by growth equations of the Gompertz form, from which could be derived estimates of the instantaneous and fractional rates of deposition of these metals in the foetal body.3. Between the 80th and 144th day of gestation the instantaneous rates of deposition of the metals increased exponentially, and at the end of pregnancy were calculated to be 0.24 and 2.0 mg Cu and Zn/d respectively in the triplet lamb foetus. The corresponding total accretions were estimated to be 10 and 69 mg respectively.4. The fractional rates of live-weight gain and of deposition of Cu were similar and decreased at similar rates; that of Zn deposition decreased much more slowly.5. The proportion of whole-body Cu estimated to be in the liver was always greater than 50 %. The amount of Zn in the liver remained constant and contributed 72 % of the total body Zn at 80 d but only 8 % at 144d.6. The relative amounts of Cu and of Zn accrued per unit body-weight gain were not constant during the development of the foetus. As foetal numbers increased the amounts of each metal deposited in the foetus decreased more rapidly than did foetal weight.7. The results are discussed in relation to the demands for Cu and Zn during pregnancy in sheep.

show abstract

Section: Discussionsupporting

confidence: 92%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

The accretion of copper and of zinc by the foetuses of prolific ewes

Williams¹,

McDonald²,

Bremner³

1978

Br J Nutr

View full text Add to dashboard Cite

show abstract

“…At Day 143, McDonald et al (1979) found the Ca, P, Mg, Na, and K concentrations to be 9.7, 5.4, 0.28, 1.9, and 1.7 g/kg fresh tissue respectively, and although the Ca and P values were lower, the Mg, Na, and K were similar to those reported in this study. As regards the trace elements, the foetal Cu, Zn, Mn, and Se concentrations at Day 143 (2.7 Cu, 21 Zn, and 0.95 mg Mn/kg fresh weight, and 43.5 Ilg Se/kg fresh weight) are similar to the Cu, Zn, Mn, and Se concentrations found by Hansard & Mohammed (1968), Moss et al (1974), Williams et al (1978), and Langlands et al (1968). However, Langlands et al (1968) reported lower concentrations of Cu and Zn (1.9 and 15 mg/kg fresh tissue respectively).…”

Section: Mineral Concentration In the Foetussupporting

confidence: 68%

“…However, data on the rate of trace element accumulation are limited to copper (Cu), zinc (Zn), selenium (Se), and manganese (Mn) in the single-bearing ewe (Hansard & Mohammed 1968;Moss et al 1974;Williams et al 1978;Langlands et al 1982). The concentrations of some trace elements in foetal liver have been determined (McDougall 1947;Pryor 1964) but little is known about the distribution of mineral elements between the various organs of the foetus.…”

Section: Introductionmentioning

confidence: 99%

Accumulation of minerals by the foetus(es) and conceptus of single- and twin-bearing ewes

Grace¹,

Watkinson

Martinson³

1986

New Zealand Journal of Agricultural Research

View full text Add to dashboard Cite

Sixty-four New Zealand Romney ewes of known dates of conception grazing a white clover-ryegrass pasture were divided into 8 groups of 8 sheep. One group was slaughtered just before mating, and one of each of the remaining groups was slaughtered at 62, 81, 100, 115, 125, 135, and 143 days of gestation. At slaughter the conceptus was removed and the foetus, placental fluids, and uterus with placental membranes attached were separated. About half the ewes bore twins, and on the 95th day of gestation the ewes were X-rayed and thereafter the slaughter groups were made up of 4 single-bearing and 4 twin-bearing ewes. All of the singleton foetuses and one member of the twin pairs were dissected and the liver, lungs, heart, kidney, spleen, thymus, and digestive tract .removed. The calcium (Ca), phosphorus (P), magnesIUm (Mg), sodium (Na), potassium (K), copper (Cu), zinc (Zn), iron (Fe), manganese (Mn), and selenium (Se) contents of the foetus(es), foetal organs, and conceptus were determined. The rates of accumulation of Ca, P, Mg, Na, K, S, Cu, Zn, Fe, Mn, and Se int? the foetus(es) and conceptus at the various gestatIOnal ages were determined from the slope of the curves relating the mineral contents of the foetus and conceptus to the gestational age.

show abstract

Tertiarization and Feminization at the Periphery: The Case of Wales

Winckler¹

1985

Restructuring Capital

View full text Add to dashboard Cite

Maternal-Fetal Utilization of Zinc by Sheep

Cited by 15 publications

References 11 publications

The accretion of copper and of zinc by the foetuses of prolific ewes

The accretion of copper and of zinc by the foetuses of prolific ewes

Accumulation of minerals by the foetus(es) and conceptus of single- and twin-bearing ewes

Tertiarization and Feminization at the Periphery: The Case of Wales

Contact Info

Product

Resources

About