Changes to Cobb 500 chick characteristics, bone ash, and residual yolk mineral reserves during time spent in the hatcher

Abstract

Previous work has identified an effect of hatch time on chick femur mineralization. This experiment assessed the impact of hatch time and a 24-h post-hatch unfed time period on chick bone mineralization and yolk mineral utilization. In early hatching chicks, yolk Mg, Zn, K, P, Fe, and Cu decreased by 40 to 50% over the 24-h post-hatch unfed time period, whereas yolk Ca and Na decreased by 25 to 40% ( P = 0.026). Yolk Sr was intermediate, decreasing by 37%. Late hatching chicks which had been hatched for no more than 30 h had a higher femur bone ash percentage compared to early hatching chicks which had spent over a 30-hour sojourn unfed in the incubator ( P = 0.013). These results indicate that removing chicks from the incubator within 30 h of their hatch is likely to benefit their femoral mineralization.

An evaluation of bird weight and diet nutrient density during early lay on ISA Brown performance, egg quality, bone characteristics, and liver health at 50 weeks of age

“…( Sweeney, 1989 ) and the crude fat by modified Randall system, where the petroleum ether was evaporated at 105°C instead of 102°C using Velp Scientifica, SER 148 solvent extraction unit (Usmate Velate, Monza and Brianza, Lombarda, Italy) ( AOAC Official Method of Analysis, Method 2003.05 Method 2006, 2022 ) at Birling Avian Laboratories, Bringelly, Australia. The Ca and P content of the diets was determined at the University of New South Wales by inductively coupled plasma optical emission spectrometry ( ICP ) using a PerkinElmer OPTIMA 7300 (PerkinElmer Inc., Waltham, MA) following digestion with nitric acid and hydrogen peroxide as described by Hopcroft et al (2020) .…”

The effect of reducing dietary calcium in prestarter diets (0–4 D) on growth performance of broiler chickens, tibia characteristics, and calcium and phosphorus concentration in blood

“…Moreover, starter diets are not specifically formulated for newly hatched chicks because requirements have been established considering the first 2 wk of rearing. After hatch, the chick depends on dietary nutrients for growth, but during the first days after hatch, there is an extra supply of Ca and very little supply of P from the residual yolk ( Yair and Uni, 2011 ; Hopcroft et al. 2020 ).…”

“…2020 ). Hopcroft et al. (2020) reported that at hatch, the Ca-to-P weight ratio in the yolk is as high as 2.9.…”

“…In the same study, the absolute Ca content in the yolk increased from 29 to 50 mg, whereas P content decreased from 115 to 55 mg. At hatch, it has been reported that more than 90% of the initial P content in the yolk has been used ( Yair and Uni, 2011 ; Uni et al., 2012 ). During the first 24 h after hatch of early-hatched chicks, Ca concentration in the residual yolk increased by 46%, while P concentration remained the same; however, total Ca content (mg) decreased by 26%, whereas P content decreased by 45% ( Hopcroft et al., 2020 ), implying a selective utilization of P compared with Ca. Overall, there are higher Ca reserves (relative to the embryo Ca utilization) than P reserves for embryo development, and at hatch, there are limited P reserves in the residual yolk.…”

Route to resilience: long term effects of incubation temperature and early feeding in broilers

“…Perhaps early fed broilers utilize the RY content differently compared to delayed fed broilers, without affecting the weight of the RY. For instance, it has been found that early fed chicks mainly utilized amino acids and minerals from the RY, whereas delayed fed chicks utilized lipids and moisture (Romanoff et al, 1944;Moran and Reinhart et al, 1980;Hopcroft et al, 2020). It can be speculated that chicks can also actively use the RY for development of the immune system, as the RY has been suggested to play a role in immune development (Murakami et al, 1992;Osama and Huwaida, 2013).…”