The effects of heating of eggs during storage, broiler breeder age, and length of egg storage on hatchability of fertile eggs were examined in this s

The current study investigated the effect of chick body (rectal) temperature during the post-hatch handling period on body weight (BW) loss, yolk sac

Three experiments were conducted to determine the effects of increased CO2 concentration during the first 3 d of incubation on albumen height and pH,

The effects of temperature fluctuation during 7 d of storage on stage of blastoderm development, embryonic mortality, and hatchability of broiler hat

1. The effect of breeder flock age, storage temperature and a short period of incubation during egg storage (SPIDES) on albumen quality, development of blastoderm, and hatchability of long-stored eggs was evaluated. 2. Hatching eggs were collected from 28-week-old (young) and 40-week-old (prime) Ross female line grandparent flocks and were stored for 14 d at 12, 15 or 18°C. During storage, the eggs were either kept continuously in the storage room (control) or were subjected to SPIDES treatment. 3. Embryonic development was more advanced in eggs from the prime flock, exposed to SPIDES and warmer (18°C) storage temperature (P≤0.05). There was a difference in the albumen pH for flock ages (P0.05). On d 14 of storage, albumen pH was positively (P<0.05) correlated with storage temperature. Hatchability was higher in the prime flock (P<0.05). 4. At both flock ages, hatchability increased (P<0.05) by storing the eggs at 15°C, compared to 18°C, with 12°C intermediate. The hatchability improvement was due to reduced early embryonic mortality. 5. The SPIDES treatment decreased late embryonic mortality and the percentage of second-grade chicks (P<0.05), which increased the hatchability of fertile eggs (P<0.05). SPIDES only reduced (P<0.05) early embryonic mortality in eggs stored at 18°C. 6. The highest hatchability was observed in the eggs stored at 15°C and exposed to one SPIDES treatment during 14 d storage.

This study investigated the effects of broiler chick hatching time on the percentage of the yolk sac and subsequent broiler live performance. Broiler hatching eggs were obtained from a commercial flock at 55 wk of age and were stored for 2 d at 18°C and 75% relative humidity (RH) prior to incubation. Chicks were identified as hatching Early (471-477 h), Middle (480-486 h), and Late (494-510 h). All chicks were removed from the trays at 510 h of incubation. Body weight (BW) and yolk weight (YW) were determined at emergence from the shell (initial hatch time) and at placement on feed. Chicks were permanently identified by hatch time with neck tags, feather sexed, weighed, and introduced to feed and water in litter floor pens. Broiler BW and feed consumption (FC) were then determined 7, 21, and 35 d of age. Mortality was recorded daily. Although the percentage of the yolk was similar at hatch time, it was less in Early compared to Middle and Late chicks at placement (p≤0.05). Broiler chick BW was greater at placement in Late chicks compared to Early and Middle chicks (p≤0.05) but this advantage disappeared by 7 d because Late chicks consumed less feed to 7 d (p≤0.05). Early hatched broilers exhibited greater BW than Late with Middle broilers intermediate at 35 d (p≤0.05). There were no significant differences in feed consumption and feed conversion ratio (FCR) at 35 d of age. Additionally, late hatch chicks exhibited greater mortality. Overall, live performance of Late hatching chicks, judged by mortality and BW at 35 d, was reduced compared to Early hatching chicks.