Characterization of feed intake and estradiol-17 β during gestation and lactation in twin-bearing ewes

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Abstract

The role of estradiol-17 β (E2) in the regulation of feed intake was investigated in two trials. Trial 1, ten twin-bearing Rambouillet ewes (64 kg, breeding weight) were individually fed corn silage ad libitum daily during the last 60 d of gestation and the first 30 d of lactation. Jugular blood samples were collected weekly for E2 analysis. In trial 2, ovariectomized Rambouillet ewes (64 kg) were administered implants containing E2 (n = 9) or sham implanted (n = 9). Implants were made from three 15-cm lengths of silastic tubing (3.35 mm i.d., 4.65 mm o.d.). Individual daily ad libitum corn silage intake was determined. Feed intake decreased (linear, P < 0.02; quadratic, P < 0.02) during gestation and increase (quadratic, P < 0.01) during lactation. Feed intake decreased as concentrations of E2 in plasma increased (r = −0.46; P < 0.01) during gestation. In trial 2, implantation of E2 decreased feed intake (time × treatment, P < 0.01). Concentrations of E2 in plasma were higher (P < 0.01) in E2 than in sham-implanted ewes (16.6 vs < 2 pg/ml, respectively). Increased concentrations of E2 in plasma during late gestation appeared to be an important factor involved in decreased feed intake.

References (43)

  • A.W. Bell et al.

    Chronic heat stress and prenatal development in sheep. 1. Conceptus growth and maternal plasma hormones and metabolites

    J. Anim. Sci.

    (1989)
  • J.R.G. Challis

    Sharp increase in free circulating oestrogens immediately before parturition in sheep

    Nature

    (1971)
  • M.L. Day

    Endocrine Mechanisms Involved in Regulation of the Pubertal Phase in Beef Heifers

  • A. Faure et al.

    Immediate, short- and long-term opposite effects of oestradiol-17 β on glucose metabolism in rat adipocytes: Relationship with the biphasic changes in body weight and food intake

    J. Endocrinol.

    (1984)
  • C.L. Ferrell et al.

    Growth, development and composition of the udder and gravid uterus of beef heifers during fetal growth

    J. Anim. Sci.

    (1976)
  • J.M. Forbes

    The physical relationships of the abdominal organs in the pregnant ewe

    J. Agric. Sci.

    (1968)
  • J.M. Forbes

    Voluntary food intake of the pregnant ewe

    J. Anim. Sci.

    (1970)
  • J.M. Forbes

    Effects of estradiol-17 β on voluntary food intake in sheep and goats

    J. Endocrinol.

    (1972)
  • J.M. Forbes

    The effects of sex hormones, gestation and lactation on digestion, metabolism and voluntary food intake

  • J.M. Forbes et al.

    Silage as a feed for pregnant ewes

    Anim. Prod.

    (1967)
  • D.W. Friend

    Self-selection of feeds and water by swine during gestation and lactation

    J. Anim. Sci.

    (1971)
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      We speculated that the surge in blood estrogen might be responsible for the depression in feed intake before parturition [12]. Green et al [13] reported a significant negative correlation (r = −0.46) between feed intake and serum estradiol-17β concentrations in the blood of late gestation ewes. Injection of estradiol-17β reduced feed intake in lactating cows [12]; however, administration at day 276 of gestation to achieve blood concentrations similar to those at parturition did not depress feed intake [14].

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