Alimentation, fertilité et bien-être des oiseaux reproducteurs domestiques : des liens complexes

Abstract

Chez les oiseaux, comme toutes autres espèces, la nutrition et plus particulièrement le métabolisme énergétique influence la fonction de reproduction. Les modèles d’oiseaux hyperphagiques ont permis de montrer l’effet négatif dans les deux sexes d’une suralimentation, alors qu’une restriction alimentaire pendant leur croissance augmente les taux de ponte et la durée de la période fertile. Cependant les mécanismes qui sous-tendent les relations entre la nutrition, le métabolisme énergétique et la fonction de reproduction sont mal connus. Ces changements du statut nutritionnel et métabolique peuvent être transmis à l’axe de la reproduction (hypothalamus, hypophyse et gonades) aussi bien par les modifications des concentrations hormonales en insuline, adipocytokines, etc., que par celles des substrats énergétiques eux mêmes : glucose, acides gras et acides aminés. Nous rappellerons brièvement ici les effets des différents composants présents dans l’alimentation et les conséquences sur la reproduction. Les propositions d’utiliser un rationnement qualitatif seront également abordées : existe-t-il des méthodes alternatives impliquant une restriction qualitative plutôt que quantitative.

Effect of dietary energy level on body weight, testicular development and semen quality of local barred chicken of the western highlands of Cameroon

“…The testicular development of roosters with high body weight at 8 weeks was significantly higher than that of other cocks. This result supported the findings of Brière et al [17] and El-Dlebshany [23] who reported that high growth performance leads to early sexual ma-turation. High body weight gain during prepubertal period seems to involve an acceleration of the increase in testes size.…”

“…Semen characteristics of roosters fed with the highest dietary energy (FP3) were relatively lower when compared to those of cocks fed with the lowest dietary energy (FP1). In birds, Brière et al [17] reported that intratesticular hyperthermia resulting from high dietary energy intake may lead to reduction of sperm production. Intratesticular hyperthermia acts by altering the functional state of spermatogonia stock [17].…”

“…Dietary energy level has been reported by many authors to affect performance trait such as body weight, delayed sexual maturity, semen production and quality in the male bird [15][16][17]. It has been reported that hypoenergetic diet leads to excessive weight gain [17,18] and consequently induce early sexual maturity and reduce fertility in male broiler [17]. Kirby et al [19] reported that increase in calorie intake may lead to an increase in testes weight with no apparent increase in spermatogenic efficiency.…”

“…Kirby et al [19] reported that increase in calorie intake may lead to an increase in testes weight with no apparent increase in spermatogenic efficiency. Adequate nutrition is therefore essential to maintain the breeding flock in good reproductive condition [17]. Age at sexual maturity has long been considered as an important factor that determines fecundity trait and affects subsequent performances [20][21][22].…”

“…Age at sexual maturity has long been considered as an important factor that determines fecundity trait and affects subsequent performances [20][21][22]. In cock flock, Brière et al [17] reported that sexual precocity is related to early testicular regression. Kirk et al [23] and Walsh and Brake [24] revealed that one of the major problems encountered with commercial broiler breeder flocks has been the often dramatic decrease in fertility during the latter part of laying period, particularly after 50 weeks of age.…”