Hatching system and time effects on broiler physiology and posthatch growth.

A multilevel housing system for broilers was developed, named Patio (Vencomatic BV, Eersel, the Netherlands), in which the hatching and brooding phase are combined. In a Patio system, climate conditions differ from those provided in the hatchers currently in use. We compared the physiology of broilers hatched in a hatcher or in a Patio system, and included the effects of hatching time.

Interaction between ascites susceptibility and CO during the second half of incubation of two broiler lines. Effect on embryonic development and hatching process.

1. Because CO(2) during the second half of incubation is known to influence air cell and blood gases, and embryo development, it is postulated that post-hatch development and ascites sensitivity could also be influenced. 2.

Effect of delayed feed access on production and blood parameters of layer-type chicks.

A total of 684 Hisex Brown day-old chicks were studied. The chicks were randomly assigned into three groups as follows: (1) chicks with immediate feed access; (2) chicks with 48 h delay in feed access, and (3) chicks with 72 h delay in feed access. For each group, chicks were assigned into 4 replications of 57 birds each.

Effect of macronutrient ratio of the pre-starter diet on broiler performance and intermediary metabolism.

The aim of this study was to investigate the influence of isoenergetic substitution between the three energy delivering macronutrients in pre-starter diets on performance and intermediary nutrient metabolism in broiler chickens. From hatch until 5 days of age, 600 chicks, collected during peak of hatch, were fed one of the three experimental pre-starter diets with isoenergetic (13 MJ metabolisable energy/kg) substitutions between fat (43 vs. 108 g/kg), protein (126 vs.

Critical assessment of chick quality measurements as an indicator of posthatch performance.

For hatcheries, not only is it important to have a high level of hatchability, but the quality of the chicks provided also has to be good, because broiler farmers are looking for chicks with a high growth potential, resulting in a greater slaughter yield at the end of the rearing period. However, chick quality has proven to be a difficult and subjective matter to define. Therefore, the aim of this study was to investigate the predictive value of different chick quality measurements for BW at slaughter age.

The effect of nonventilation during early incubation on the embryonic development of chicks of two commercial broiler strains differing in ascites susceptibility.

Despite thorough selection during the last decade, the incidence of ascites is still high in modern broiler strains. Although ascites occurs mostly at the end of the rearing period, there are indications that the etiology of this problem may have started during embryonic development. Recent studies have shown that the post-hatch performance of the broiler chick might be influenced by changing the environmental conditions in the incubator during embryonic development.

Changes in acid-base balance and related physiological responses as a result of external hypercapnia during the second half of incubation in the chicken embryo.

This study investigated the effect of high CO2 (4%) from embryonic day (ED)10 until ED16 on the acid-base balance and related parameters in the chicken embryo. From ED10 to ED16, blood was taken from a vein from the chorioallantois membrane and was analyzed for pH, partial pressure of CO2, partial pressure of O2 (pO2), [HCO3(-)], [K+], and [Ca2+]. Allantoic fluid was taken for measurement of pH, NH3-N, phosphate, and calcium concentration.

Effect of four percent carbon dioxide during the second half of incubation on embryonic development, hatching parameters, and posthatch growth.

In this study, broiler embryos were exposed during the second half of incubation [embryonic day (ED) 10 until ED18] to 4% CO(2). The CO(2) was set to reach 2% on ED11 and 4% from ED12 onward. Two experiments were conducted with the same setup.

Acid-base balance in chicken embryos (Gallus domesticus) incubated under high CO2 concentrations during the first 10 days of incubation.

Recent studies show the importance of differential CO2 levels during the first half of incubation of chicken eggs on embryonic and postnatal growth. However, it is not known how external higher CO2 levels affect embryonic acid-base balance. In this study, the effect of an early rise in CO2, between 25th and 96th hour of incubation to 1.

Embryonic developmental plasticity of the chick: increased CO(2) during early stages of incubation changes the developmental trajectories during prenatal and postnatal growth.

This study investigated the effect of non-ventilation of the incubator during the first 10 days of incubation on carbon dioxide (CO(2)) concentrations in the incubator and its effects on the embryonic and post-hatch development of the chicken (Gallus gallus). Two different incubation conditions were created, one incubator was kept at standard conditions, with adequate ventilation (V) and a second incubator was non-ventilated (NV) during the first ten days of incubation, allowing the CO(2) to rise. After the first 10 days, both incubations were continued under standard conditions.