Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-28T04:12:25.821Z Has data issue: false hasContentIssue false

Endocrine aspects of development: new challenges for the control of incubation process

Published online by Cambridge University Press:  18 September 2007

E. Decuypere*
Affiliation:
Laboratory of Physiology and Immunology of Domestic Animals, Kasteelpark Arenberg 30, 3001, Heverlee, Belgium
V. Bruggeman
Affiliation:
Laboratory of Physiology and Immunology of Domestic Animals, Kasteelpark Arenberg 30, 3001, Heverlee, Belgium
*
*Corresponding author: eddy.decuypere@agr.kuleuven.ac.be
Get access

Abstract

An increased knowledge of endocrine systems during incubation not only results in a better understanding of fundamental aspects of embryonic development, but also may lead to new practical applications. A first and immediate aspect is the possibility of early sex diagnosis based on current knowledge of sex determination. The current practice of killing day-old male chicks of layers results essentially from the improved efficiency of modern egg and meat lines, which were selected in opposite directions. The disposal of unwanted male chicks from layer lines causes increased welfare and ethical concern. Therefore, attempts have been made to interfere with sex determination or to identify the unwanted gender of the embryo at a certain stage of development (e.g. based on endocrine differences) where public concern is no longer a point of resistance against elimination. Thyroid hormones as well as glucocorticoids are known to be involved in several events leading to hatch and in the quality of the hatchling. Both seem to be strongly influenced by a common hypothalamic factor in the late chick embryo: corticotrophin-releasing hormone (CRH), CRH-related urocortines or analogues for CRH-receptor activity may be combined with in ovo vaccination for stimulating or synchronizing hatching activity. A next question to be asked is whether incubation conditions that produce the best hatchability also automatically result in chicks of the highest quality with the best desired postnatal performance. During prenatal development, most of the functional systems develop from an open loop system without feedback into a closed control system with feedback. This is already documented for endocrine systems such as the thyroid, the corticotroph and the gonadal axis. For functional systems, critical periods seem to exist and it is presumed that these coincide with the transition from an open into a closed feedback control system. In consequence, variation in incubation conditions such as temperature may induce a lifelong determination of physiological control systems, most probably via long-term changes in the expression of related effector genes and this may be defined as epigenetic adaptation. This opens possibilities to improve incubation conditions, not only in view of hatchability/chick quality but also taking long-term effects into account. Also it may redirect, at least to some extent, development as a function of the aims set forward, e.g. metabolic conditioning.

Type
Reviews
Copyright
Copyright © Cambridge University Press 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Avrutina, A.J., Galpern, I.L. and Kisljuk, S.M. (1985) Stimulation of adrenals during the critical periods of development and production in fowls. World's Poultry Science Journal 41: 108114.CrossRefGoogle Scholar
Buys, N., Dewil, E. and Decuypere, E. (1997) Embryonic characteristics and incubation conditions influence susceptibility to the ascites syndrome. XIth International Congress of the World Veterinary Poultry Association, Budapest, Hungary, p 139.Google Scholar
Buyse, J., Decuypere, E. and Veldhuis, J.D. (1997). Compensatory growth of broiler chickens is associated with an enhanced pulsatile growth hormone (GH) secretion: preferential amplification of GH secretory burst mass. British Poultry Science 38: 291296.CrossRefGoogle ScholarPubMed
Buys, N., Dewil, E., Gonzales, E. and Decuypere, E. (1998) Different CO2 levels during incubation interact with hatching time and ascites susceptibility in two broiler lines selected for different growth rate. Avian Pathology 27: 605612.CrossRefGoogle ScholarPubMed
Coleman, M.A. and Coleman, G.E. (1991) Ascites control through proper hatchery management. Misset World Poultry 7: 3335.Google Scholar
Decuypere, E., Scanes, C.G. and Kuhn, E.R. (1983) Effects of glucocorticoids on circulating concentrations of thyroxine (T4) and triiodothyronine (T3) and on peripheral monodeiodination in pre-and post-hatching chickens. Hormone Metabolism Research 15: 233236.CrossRefGoogle ScholarPubMed
Decuypere, E., Iqbal, A., Michels, H., Kuhn, E.R., Schneider, R. and Adb El Azeem, A. (1988) Thyroid hormone response to thyrotropin releasing hormone after cold treatment during pre- and postnatal development in the domestic fowl. Hormone Metabolism Research 20: 484489.CrossRefGoogle ScholarPubMed
De Groef, B. (2003) Hypotalamic control of thyrotropin secretion in the chicken. Phd Thesis, Catholic University of Leuven.Google Scholar
Dewil, E., Buyse, J., Veldhuis, J.D., Mast, J., De Coster, R. and Decuypere, E. (1998) In ovo treatment with an aromatase inhibitor masculinzes postnatal hormone levels, abdominal fat pad content, and GH pulsatility in broiler chickens. Domestic Animal Endocrinology 15: 115127.CrossRefGoogle ScholarPubMed
Geris, K.L., Darras, V.M., Berghman, L.R. and Kuhn, E.R. (1995) Influence of corticotrophinreleasing factor on the in vitro thyroxine and thyrotropin secretion in newly hatched fowl. Belgian Journal Zoology 125: 143156.Google Scholar
Geris, K.L., Kotanen, S.P., Berghman, L.R., Kuhn, E.R. and Darras, V.M. (1996) Evidence of a thyroptropin-releasing activity of ovine corticotrophin-releasing factor in the domestic fowl (Gallus domesticus) General and Comparative Endocrinology 104: 139146.CrossRefGoogle Scholar
Iqbal, A., Decuypere, E., Schneider, R. and Kuhn, E.R. (1986).Thyroid hormone response to TRH after cold treatment during a critical period in the hypophyseal-thyroid axis development in the chicken. IRCS Medical Science 14: 401.Google Scholar
Kuhn, E.R., Geris, K.L., Van Der Geyten, S., Mol, K.A. and Darras, V.M. (1998). Inhibition and activation of the thyroidal axis by the adrenal axis in vertebrates. Comparative Biochemical Physiology part A 120: 169174.CrossRefGoogle ScholarPubMed
Phelps, P., Bhutada, A., Bryan, S., Chalker, A., Ferrell, B., Neuman, S., Ricks, C., Tran, H. and Butt, T. (2003) Automatic identification of male layer chicks prior to hatch. World's Poultry Science Journal 59: 3339.Google Scholar
Rombauts, L.,Vanmontfort, D., Verhoeven, G. and Decuypere, E. (1992) Immunoreactive inhibin in plasma, amniotic fluid and gonadal tissue of male and female chick embryos. Biology of Reproduction 46: 12111216.CrossRefGoogle ScholarPubMed
Rombauts, L., Berghman, L.R., Vanmotfort, D., Decuypere, E. and Verhoeven, G. (1993) Changes in immunoreactive FSH and inhibin in developing chicken embryos and the effects of estradiol and the aromatase inhibitor R76713. Biology of Reproduction 49: 549554.CrossRefGoogle ScholarPubMed
Veldhuis, J.D. (1995) The neuroendocrine regulation and implications of pulsatile GH secretion: Gender effects. The Endocrinologist 5: 198213.CrossRefGoogle Scholar
Veldhuis, J.D., Carlson, M.L. and Johnson, M.L. (1987) The pituitary gland secretes in bursts: appraising the nature of glandular secretory impulses by simultaneous multiple-parameter deconvolution of plasma hormone concentrations. Proceedings National Academy Science USA 84: 76867690.CrossRefGoogle ScholarPubMed
Veldhuis, J.D., Iranmanesh, A., Rogol, A.D. and Urban, R.J. (1995) Regulatory actions of testosterone on pulsatile growth hormone secretion in the human: studies using deconvolution analysis. In: The somatotrophic axis and the reproductive process in health and disease. Adashi, E.Y., Thorner, M.O. (eds.) Springer-Verlag, New York, pp 4057.CrossRefGoogle Scholar
Woods, J.E., Simpson, R.M. and Moore, P.L. (1975). Plasma testosterone levels in the chick embryo. General and Comparative Endocrinology 27: 543547.CrossRefGoogle ScholarPubMed
Woods, J.E. and Brazzill, D.M. (1981) Plasma 17β-estradiol levels in the chick embryo. General and Comparative Endocrinology 44: 3743.CrossRefGoogle ScholarPubMed