ABSTRACT
Se evaluó el efecto del incremento de la temperatura de incubación en huevos de gallina Araucana sobre la tasa de eclosión, la mortalidad embrionaria, el peso del polluelo, del saco vitelino y de los órganos internos. Los huevos (n= 426) fueron distribuidos al azar en: a) grupo Control (n=215), incubados a 37,5 °C por 21 días y b) grupo Experimental (n= 211), incubados a 39,5 °C, por 18 días, disminuyéndose a 37,5 °C los 3 días restantes. En ambos grupos la incubación se realizó con una humedad relativa constante del 55 %. La tasa de mortalidad embrionaria total fue significativamente menor (P 0,05) para el grupo Control (14,9 vs 44,1 %) y consecuentemente la tasa de eclosión fue significativamente mayor (P 0,05) en este mismo grupo (97,8 vs. 80,5 %). El peso promedio de los polluelos y del saco vitelino a las 36 h post eclosión fue significativamente diferente (P 0,05) entre ambos grupos (37,1 vs. 36,3 y 2,5 vs 6,2 g para el grupo Control y Experimental respectivamente). Por otra parte, el peso de todos los órganos internos fue menor (P 0,05) en polluelos del grupo Experimental. Se concluye que el uso de una temperatura de incubación de 39,5 C por 18 días en huevos de gallina araucana influye negativamente, aumentando la mortalidad embrionaria, disminuyendo la tasa de eclosión, el peso del polluelo y de los órganos internos, y aumentando el peso del saco vitelino.
The aim of this study was to evaluate the effect of increasing incubation temperature of Araucana hen eggs on embryo mortality, hatchability,chick, yolk sac and internal organs weight. Eggs (n= 426) were randomly distributed into: a) Control group (n= 215), which were incubated at 37.5 °C for 21 days or b) Experimental group (n= 211), which were incubated at 39.5 °C, for 18 days and then at 37.5 °C for the remaining 3 days. In both groups eggs were incubated with a relative humidity of 55 %. The embryo mortality rate was greater (P 0.05) for the experimental than the control group (44.1 vs. 14.9 % respectively). On the contrary, hatching rate was greater (P 0.05) for the control than the experimental group (97.8 vs. 80.5 % respectively). The average weight of chicks, at 36 h of age, was lower (P 0.05) for the experimental than control group (36.3 vs. 37.01 g respectively). Also, increasing incubation temperature reduced (P 0.05) internal organs weight of chicks in the Experimental compared to Control group. On the other hand, yolk sac weight was reduced (P <0.05; 2.5 vs. 6.2 g for Control and Experimental group respectively). We conclude that increasing the incubation temperature of Araucana hen eggs up to 39.5 °C for 18 days has a negative effect on embryo survival, hatchability, chick and internal organs weight and absorption of yolk.
Subject(s)
Animals , Chick Embryo , Chickens/growth & development , Temperature , Body Weight , Chickens/anatomy & histology , Eggs , Mortality , Organ SizeABSTRACT
O tamanho dos ovos está relacionado com a sobrevivência e o crescimento de filhotes de aves precociais. A inter-relação entre ovo e filhote pode ser importante para a produção animal, fornecendo subsídios para decisões estratégicas de economia, manejo e bem-estar animal. Este estudo analisou a relação entre o peso dos ovos antes da incubação e o desenvolvimento de filhotes de avestruzes (N=48) aos quinze dias de idade. Os filhotes foram criados em grupos, em berçários, com alimentação comercial e sem cuidado parental. Nos filhotes, mensurou-se o peso, a altura da cernelha e o comprimento do tarso-metatarso. Houve uma significativa diferença nos pesos dos ovos, mas as medidas corporais equivalentes dos filhotes não foram estatisticamente diferentes. Em concordância com estudos em outras espécies de aves, o peso do ovo não parece influenciar o crescimento dos filhotes de avestruzes até os 15 dias de vida, em avestruzes.
The size of the eggs is related to survival and chick growth in precocial birds. The interrelationship between egg and chick development can be important for the animal production, supplying data for strategic decisions of economy, handling and animal welfare. This study analyzed the relation between the weight of the eggs and the development of ostrich chicks (N=48) at age of fifteen days old. The chicks were kept in indoor nurseries, in groups, without parental care, and fed commercial feed. It was recorded the weight, the back height and the length of the tarsus-metatarsus. There was a significant difference in the weight of the eggs, but the correspondent body chicken measures were not statistically different. In agreement to the studies in other species of birds, the weight of the egg does not seem to influence the growth of the ostriches at fifteen days old.