Study Questions

1. Ergot toxicity causes a number of physiological responses in animals. Ergotism is caused by the ingestion of ergot alkaloids that are produced by endophytic fungi that live in the seed heads of various grains. One response is a severe decrease in prolactin secretion from the pituitary. If a pregnant female mammal is exposed to ergot alkaloids at around the time of parturition, what effect would you expect on her ability to lactate?

2. If a late pregnant female mammal is injected with progesterone starting prior to parturition and continuing until after parturition, what would you expect to happen to her ability to lactate immediately after parturition?

3. If you removed a piglet from the sow immediately after birth and fed it cow colostrum and then took a blood sample from the piglet, what type of antibodies would you find in the piglet's blood? Explain why you draw your conclusion. What type of antibodies would you find in the piglet's blood if you left it with the sow after birth and then fed it cow colostrum at about 48 hours after birth? Explain why you draw your conclusion.

4. Is colostrum that has very low concentrations of IgG of any value to the newborn calf? Explain why you draw your conclusion.

References

Lactogenesis

Tucker, HA (1994) Lactation and its hormonal control. Ch. 57, In: The Physiology of Reproduction, 2nd edition, Eds. E. Knobil, J. Neill, et al. Raven Press, Ltd., New York. p. 1065.

Oka, T, Yoshimura, M, Lavandero, S, Wada, K, Ohba, Y 1991 Control of growth and differentiation of the mammary gland by growth factors. J. Dairy Sci. 74:2788-2800.

Forsyth, IA 1989 Growth factors in mammary gland function. J. Reprod. Fert. 85:759-770.

Wilde CJ, Hurley WL 1996 Animal models for the study of milk secretion. J. Mammmary Gland Biol. Neoplasia 1:123-134.

Streuli, CH 1993 Extracellular matrix and gene expression in mammary epithelium. Sem. Cell Biol. 4:203-212.

Hormonal Induction of Lactation

Smith, K.L. and F.L. Schanbacher. 1973. Hormone induced lactation in the bovine. I. Lactational performance following injections of 17ß-estradiol and progesterone. J. Dairy Sci. 56:738-743.

Collier, R. J., D., E. Bauman, and R. L. Hays. 1975. Milk production and reproductive performance of cows hormonally induced into lactation. J. Dairy Sci. 58:1524.

Collier, R. J., D., E. Bauman, and R. L. Hays. 1977. Effects of reserpine on milk production and serum prolactin of cows hormonally induced into lactation. J. Dairy Sci. 60:896.

Chakriyarat, S., H. H. Head, W. W. Thatcher, F. C. Neal, and C. J. Wilcox. 1978. Induction of lactation: lactational, physiological, and hormonal responses in the bovine. J. Dairy Sci. 61:1715.

Peel, C. J., J. W. Taylor, I. B. Robinson, A. A. McGowan, R. D. Hooley, and J. K. Findlay. 1978. The importance of prolactin and the milking stimulus in the artificial induction of lactation in cows. Aust. J. Biol. Sci. 31:187.

Harness, J. R., R. R. Anderson, L. J. Thompson, D. M. Early, and A. K. Younis. 1978. Induction of lactation by two techniques: success rate, milk composition, estrogen and progesterone in serum and milk, and ovarian effects. J. Dairy Sci. 61:1725.

Kensinger, R. S., D. E. Bauman, and R. J. Collier. 1979. Season and treatment effects on serum prolactin and milk yield during induced lactation. J. Dairy Sci. 62:1880.

Croom, W. J., R. J. Collier, D. E. Bauman, and R. L. Hays. 1976. Cellular studies of mammary tissue from cows hormonally induced into lactation: histology and ultrastructure. J. Dairy Sci. 59:1232.

Davis, S. R., R. A. S. Welch, M. G. Pearce, and A. J. Peterson. 1983. Induction of lactation in nonpregnant cows by estradiol-17ß and progesterone from an intravaginal sponge. J. Dairy Sci. 66:450-457.

Sawyer, G. J., W. J. Fulkerson, G. B. Martin, and C. Gow. 1986. Artificial induction of lactation in cattle: initiation of lactation and estrogen and progesterone concentrations in milk. J Dairy Sci. 69:1536.

Fleming, J. R., H. H. Head, K. C. Bachman, H. N. Becker, and C. J. Wilcox. 1986. Induction of lactation: histological and biochemical development of mammary tissue and milk yield of cows injected with estradiol-17ß and progesterone for 21 days. J. Dairy Sci. 69:3008.

Immunglobulin transport in the mammary gland

Larson et al., 1980, J. Dairy Sci. 63:665
Guidry et al., 1980, Vet. Immunol. Immunopathol. 1:329
Stott et al., 1981, J. Dairy Sci. 64:6459
Devery-Pocius and Larson, 1983, J. Dairy Sci. 66:221
Staley, TE, Bush, LJ 1985 Receptor mechanisms of the neonatal intestine and their relationship to immunoglobulin absorption and disease. J. Dairy Sci. 68:184-205.

Intestinal protective factors

Welsh, JK, May, JT 1979 Anti-infective properties of breast milk. J. Pediatr. 94:1-9.
Hanson, LA, Carlsson, B, Jalil, F, Hahn-Zoric, M, Hermodson, S, Karlberg, J, Thiringer, K, Zaman, S 1988 Antiviral and antibacterial factors in human milk. In Biology of Human Milk, Ed. LA Hanson, Nestle Nutrition Workshop Series, Vol. 15, Nestle Ltd, Vevey/Raven Press, NY.

Bioactive factors in milk

Koldovsky, O 1989 Search for role of milk-borne biologically active peptides for the suckling. J. Nutr. 119:1543-1551.
Koldovsky, O 1995 Do hormones in milk affect the function of the neonate intestine? Amer. Zool. 35;446-454.
Lo, CW, Kleinman 1996 Infant formula, past and future: opportunities for improvement. Am. J. Clin. Nutr. 63:646S-650S.
Lonnerdal, B 1985 Biochemistry and physiological function of human milk proteins. Am. J. Clin. Nutr. 42:1299-1317.
Odle, J, Zijlstra, RT, Donovan, SM 1996 Intestinal effects of milkborne growth factors in neonates of agricultural importance. J. Anim. Sci. 74:2509-2522.