title: Single stage incubators and Hypercapnia during incubation affect the vascularization of the chorioallantoic membrane in broiler embryos.
abstract: Incubation management can have direct effects on neonate health and consequently affect post-hatching development. The effects of incubation in multiple and single stage incubators with different concentrations of CO2were evaluated in terms of the vessel density in the chorioallantoic membrane, hatching, heart morphology, and body development of the neonate up to the tenth day. A total of 2,520 fertile eggs were used and distributed in a completely randomized design with 4 levels of CO2in 4 single-stage incubators (4,000; 6,000; 8,000; and 10,000 ppm) and a control treatment based on multiple-stage incubation, totaling 5 treatments. The levels of CO2were used during the first 10 d of the incubation period, and after this period, all eggs were submitted to the same level of CO2(4,000 ppm). Eggs that were incubated in multiple-stage incubators presented a lower percentage of vessels in the chorioallantoic membrane, lower yolk absorption by the embryo, wall depth of the right ventricle, and greater humidity losses in the eggs when compared to eggs in the single-stage incubators. The eggs submitted to hypercapnia, between 5,000 and 6,000 ppm of CO2, had a higher percentage of vessels in the chorioallantoic membrane; the embryos originating from these eggs had higher weight, with higher relative weight of the liver. However, the same levels reduced the yolk absorption. Single-stage incubation with moderate levels of hypercapnia is an efficient tool to be adopted by the hatcheries when attempting to improve chick quality.
authors: Laboratory of Poultry Experimentation, Federal University of Parana - Palotina, 85950-000, Parana, Brazil jimfernandes@ufpr.br.
authors: J I M
authors: JI
authors: Fernandes
authors: Laboratory of Poultry Experimentation, Federal University of Parana - Palotina, 85950-000, Parana, Brazil.
authors: C
authors: C
authors: Bortoluzzi
authors: Laboratory of Poultry Experimentation, Federal University of Parana - Palotina, 85950-000, Parana, Brazil.
authors: J M
authors: JM
authors: Schmidt
authors: Laboratory of Poultry Experimentation, Federal University of Parana - Palotina, 85950-000, Parana, Brazil.
authors: L B
authors: LB
authors: Scapini
authors: Department of Animal Science, State University of Maringa, 87020-900, Parana, Brazil.
authors: T C
authors: TC
authors: Santos
authors: Department of Animal Science, State University of Maringa, 87020-900, Parana, Brazil.
authors: A E
authors: AE
authors: Murakami
mesh_terms: D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism*; D002642:Chick Embryo / Q000254:growth & development; D002645:Chickens / Q000254:growth & development* / Q000378:metabolism; D049033:Chorioallantoic Membrane / Q000187:drug effects / Q000254:growth & development; D004305:Dose-Response Relationship, Drug; D007185:Incubators / Q000662:veterinary*; D011897:Random Allocation; D012098:Reproduction
chemical_list: D002245:Carbon Dioxide
keywords: angiogenesis; hypercapnia; incubators