![]() In experiment 2, high translucent eggs from organic fed breeders hatched later than eggs from the other three treatment groups and additionally, high egg translucency resulted in lower residual yolk weight and higher heart and liver percentage of YFBM compared to low egg translucency. Chicken quality showed ambiguous results between experiment 1 and 2 regarding trace minerals source in the breeder diet. Embryonic heat production and tibia ossification were not affected by trace minerals source or egg translucency. In inorganic trace minerals fed breeders, a high egg translucency resulted in a higher egg weight loss than a low egg translucency, whereas this difference was not seen in organic trace minerals fed breeders. In both experiments, an interaction between trace minerals source and translucency score was found for egg weight loss during incubation. Egg quality was not affected by breeder trace minerals source or egg translucency in both experiments. At hatch, chicken quality was assessed, including tibia biophysical characteristic. ![]() During incubation, metabolic heat production of the embryos (d 8 (E8) to 19 of incubation) and tibia ossification (E8.5 to E14.5) were determined daily. Egg composition and bacterial load on the eggshell were analysed in fresh eggs. In the first experiment, eggs from old breeders (55 to 57 wk) and in the second experiment, eggs from prime breeders (34 to 36 wk) were used. In two experiments, interactions between trace mineral (Zn, Mn, Cu, Se) source (organic or inorganic) in the broiler breeder diet and egg translucency (high or low) on egg characteristics and embryonic development were investigated. No effect on humoral immune response or disease resilience was found. Although beneficial effects of HF and OH systems were found for young breeder flock offspring on chick quality at hatch and body weight posthatch, only one effect of alternative hatching systems on welfare and health indicators were found. No differences between treatment groups were observed. Animals were vaccinated with a live attenuated infectious bronchitis vaccine virus (IBV) was applied at day 28 to address treatment related differences to disease resilience, and the expressions of inflammation and epithelial integrity related genes in the trachea and histo-pathological changes in the trachea were examined at three days after vaccine administration. No effect was observed on the dynamics of a humoral immune response after NCD vaccination, given at day 0 and 14 of age, as no differences between NCD titres were found at day 18. Chick quality at hatch and performance until 35 days of age was improved in the HF and OH compared to HH treatment, but only minor effects were found on the welfare indicators: footpad dermatitis, hock burn, cleanliness, skin lesion and gait score. A total of 24 pens were used in a completely randomized block design, with 8 pens per hatching system and 30 chickens per pen. This study evaluated effects of hatching systems on chick quality, health and welfare of young breeder flock offspring, using three different hatching systems: conventional hatchery-hatched (HH), hatchery-fed (HF), and on-farm hatching (OH). Especially offspring from young broiler breeder flocks may benefit, as they have been shown to be more sensitive to preturbations than offspring from older breeder flocks. ![]() Besides beneficial effects of these alternative hatching systems on chick quality and performance, broiler health and welfare may be positively affected as well. Alternative hatching systems have been developed for broiler chickens to provide immediately feed and water after hatch and reduce the number or severity of early life stressors.
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