Andres, C. J., Green, M. L., Clapper, J. A., Cline, T. R. and Diekman, M. A. 1991. Influence of daily injections of porcine somatotropin on growth, puberty and reproduction in gilts, journal of Animal Science 69: 3754–3761.
Armstrong, J. D., Coffey, M. T., Esbenshade, K. L., Campbell, R. M. and Heimer, E. P. 1994. Concentrations of hormones and metabolites, estimates of metabolism, performance, and reproductive performance of sows actively immunized against growth hormone-releasing factor. Journal of Animal Science 72:1570–1577.
Baidoo, S. K., Lythgoe, E. S., Kirkwood, R. N., Aherne, F. X. and Foxcroft, G. R. 1992. Effect of lactation feed intake on endocrine status and metabolite levels in sows. Canadian journal of Animal Science 72: 799–807.
Buonomo, F. C. and Baile, C. R. 1991. Influence of nutritional deprivation on insulin-like growth factor-I, somatotropin, and metabolic hormones in swine. Journal of Animal Science 69: 755–760.
Clowes, E. J., Aherne, F. X. and Foxcroft, G. R. 1994. Effect of delayed breeding on the endocrinology and fecundity of sows. Journal of Animal Science 72: 283–291.
Clutter, A. C., Spicer, L. J., Woltmann, M. D., Grimes, R. W., Hammond, J. M. and Buchanan, D. S. 1995. Plasma growth hormone, insulin-like growth factor I, and insulin-like growth factor binding proteins in pigs with divergent genetic merit for postweaning average daily gain. Journal of Animal Science 73:1776–1783.
Coffey, M. T., Diggs, B. G., Handlin, D. L., Knabe, D. A., Maxwell, C. V., Noland, P. R., Prince, T. J. and Gromwell, G. L. 1994. Effect of dietary energy during gestation and lactation on reproductive performance of sows: a cooperative study. Journal of Animal Science 72: 4–9.
Davis, S. L. 1988. Recent concepts in regulation of growth by GH and IGF. Journal of Animal Science (suppl. 3) 66: 84–97.
Echternkamp, S. E., Spicer, L. J., Klindt, J., Vernon, R. K., Yen, J. T. and Buonomo, F. C. 1994. Administration of porcine somatotropin by a sustained-release implant: effect on follicular growth, concentrations of steroids and insulin-like growth factor I, and insulin-like growth factor binding protein activity in follicular fluid of control, lean, and obese gilts. Journal of Animal Science 72: 2431–2440.
Enright, W. J., Quirke, J. F., Gluckman, P. D., Breier, B. H., Kennedy, L. G., Hart, I. C., Roche, J. F., Coer, A. and Allen, P. 1990. Effects of long-term administrations of pituitary-derived bovine growth hormone and estradiol on growth in steers. Journal of Animal Science 68: 2345–2356.
Grant, S. A. 1989. Ovarian function in the gilt and lactating sow. Ph.D. thesis, University of Nottingham, UK.
Johnston, L. J., Fogwell, R. L., Weldon, W. C., Ames, N. K., Ullrey, D. E. and Miller, E. R. 1989. Relationship between body fat and post weaning interval to estrus in primiparous sows. Journal of Animal Science 67: 943–950.
Killen, J. H., Christenson, R. K. and Ford, J. J. 1992. Ovarian follicular changes after weaning in sows. Journal of Animal Science 70: 2801–2808.
King, R. H. and Dunkin, A. C. 1986. The effect of nutrition on the reproductive performance of first-litter sows. 3. The response to graded increases in food intake during lactation. Animal Production 42:119–125.
King, R. H. and Williams, I. H. 1984. The effect of nutrition on the reproductive performance of first-litter sows. 1. Feeding level during lactation and between weaning and mating. Animal Production 38: 241–247.
Kirkwood, R. N. and Aherne, F. X. 1985. Energy intake, body composition and reproductive performance of the gilt. Journal of Animal Science 60: 1518–1529.
Kirkwood, R. N. and Thacker, P. A. 1991. The influence of premating feeding level and exogenous insulin on the reproductive performance of sows. Canadian Journal of Animal Science 71: 249–251.
Kirkwood, R. N., Thacker, P. A., Guedo, B. L. and Laarveld, B. 1989. The effects of exogenous growth hormone on the endocrine status and the occurrence of estrus in gilts. Canadian Journal of Animal Science 69:931–937.
Kirkwood, R. N., Thacker, P. A. and Rajkumar, K. 1992. Effects of growth hormone and triiodothyronine on insulin-induced progesterone production by granulosa cells from prepubertal gilts. Canadian Journal of Animal Science 72: 589–593.
Klindt, H. 1986. Porcine growth hormone and prolactin secretion: the first month of postnatal life. Growth 50: 516–525.
Korenman, S. G., Stevens, R. H., Carpenter, L. A., Robb, M., Niswender, G. D. and Sherman, B. M. 1974. Estradiol radioimmunoassay without chromatography procedure, validation and normal values. Journal of Clinical Endocrinology and Metabolism 38: 718–723.
Kreider, D. L. 1975. Endocrine changes associated with embryogenesis and heat stress in gilts. Master of Science thesis, Oklahoma State University, USA.
McCusker, R. H., Wagsness, P. J., Griel, L. C. and Kavanagh, J. F. 1985. Effects of feeding, fasting and refeeding on growth hormone and insulin in obese pigs. Physiology and Behavior 35: 383–388.
Paterson, A. M. and Pearce, G. P. 1994. Plasma hormone and metabolite concentrations and the interval from weaning to oestrus in primiparous sows. Animal Reproduction Science 36: 261–279.
Quesnel, H. and Prunier, A. 1995. Endocrine bases of lactational anoestrus in the sow. Reproduction, Nutrition, Development 35: 395–414.
Ronayne, E. and Hynes, N. 1990. Measurement of plasma progesterone concentrations by extraction and non-extraction radioimmunoassays. Irish Journal of Agricultural Research 29:109–115.
Spicer, L. J. and Echternkamp, S. E. 1995. The ovarian insulin and insulin-like growth factor system with an emphasis on domestic animals. Domestic Animal Endocrinology 12: 223–245.
Statistical Analysis Systems Institute. 1985. SAS user's guide: statistics. Statistical Analysis Systems Institute Inc., Cary, NC.
Sterning, M., Rydhmer, L., Eliasson, L., Einarsson, S. and Andersson, K. 1990. A study on primiparous sows of the ability to show standing oestrus and to ovulate after weaning. Influences of loss of body weight and backfat during lactation and of litter size, litter weight gain and season. Ada Veterinaria Scandinavica 31: 227–236.
Terlouw, S. A., Rieke, A. R., Cantley, T. C., Miller, L. F. and Day, D. N. 1991. The effects of recombinant porcine somatotropin on reproductive function in gilts treated during the finishing phase. Journal of Animal Science 69: 4294–4298.
Tokach, M. D., Pettigrew, J. E., Dial, G. D., Wheaton, J. E., Croker, B. A. and Johnson, L. J. 1992. Characterization of luteinizing hormone secretion in the primiparous lactating sow: relation to blood metabolites and return-to-oestrus interval. Journal of Animal Science 70: 2195–2201.
Weldon, W. C., Lewis, A. J., Louis, G. F., Kovar, J. L., Giesemann, M. A. and Miller, P. S. 1994a. Postpartum hypophagia in primiparous sows: I. Effects of gestation feeding level on feed intake, feeding behavior, and plasma metabolite concentrations during lactation, journal of Animal Science 72: 387–394.
Weldon, W. C., Lewis, A. J., Louis, G. F., Kovar, J. L. and Miller, P. S. 1994b. Postpartum hypophagia in primiparous sows: II. Effects of feeding level during gestation and exogenous insulin on lactation feed intake, glucose tolerance, and epinephrine-stimulated release of nonesterified fatty acids and glucose. Journal of Animal Science 72: 395–403.