Full Length Research Article

RETRACTED ARTICLE: Impact of egg size on the quality of eggs, chicks, and post hatch overview of offspring during the mid stage of yield (45th week) in Hubbard broiler breeders

Javid Iqbal¹, Sohail Hassan Khan^2*, Nasir Mukhtar³, Tanveer Ahmad³

Adv. life sci., vol. 10, no. 3, pp. 368-374, September 2023
*^- Corresponding Author: Sohail Hassan Khan (sohailhassan64@gmail.com)
Authors' Affiliations

Abstract
Introduction
Methods
Results
Discussion
References 

Abstract

Background: The most significant component in influencing the performance of the laying flock is egg size. Though commercial broiler farming is in operation, little is known about how breeder hatching egg weight during middle (45^th week) phase of yield production effects on qualities of egg & chick and post-hatch Hubbard broiler growth performance.

Methods: At 45 weeks of age, hatching eggs (n=930) from a commercial broiler breeder flock were gathered as well as classified into 3 groups of egg weight: short (60.25±0.25g), medium (65.10 ± 0.31g), and large (70.07 ± 0.61g). These eggs more classified into 2 groups i.e., egg quality parameters and incubation & post hatch performance metrics. Eggs for performance measures related to incubation and post hatch as well as eggs for quality factors are two further categories into which these eggs are divided.

Result: The proportion of shell weight was higher in the eggs obtained from small egg group. The size of the eggs had an effect on the shape index and specific gravity, with larger eggs having lower values. Both male and female chicks' weight and length were significantly influenced by egg size. Data of the body weight gain indicated that as broilers age increases, impact of egg weight on post-hatch performance of chicks’ decreases. Up until age 21, female chicks' body weight gain was highly influenced by egg size. The female chicks' feed conversion ratio at day 21 of life was considerably impacted by various egg-weight categories, while it had no effect on male and female chicks at day 35.

Conclusion: Egg size favorably influenced the features of the chicks (weight and length) but without any impact on feed consumption, conversion ratio & mortality or ultimate overall live weight of the broilers.

Keywords: Egg size; Egg characteristics; Hatchling quality; Production; Feed consumption    

Retraction Note

24 Sept 2025: The Editor-in-Chief has retracted this article due to the below mentioned scientific deficiencies revealed by an internal audit.

1. The abstract and results sections claim statistically significant effects (p≤0.05) where the tables show non-significant results.

• The effect on Shell Weight % is cited as significant, but Table 1 shows p=0.062.
• The effect on Shape Index (termed "Form index" in the table) is cited as significant, but Table 1 shows p=0.086.
• The influence on female chick body weight at day 21 is cited as significant, but Table 3 shows p=0.073.
• The impact on female chick feed intake (15-21d) is cited as significant, but Table 3 shows p=0.090.
• The abstract claims the female feed conversion ratio (FCR) at day 21 was significantly impacted, but Table 3 shows p=0.807.

2. The Discussion section states, "the egg shell’s weight was about 16% of egg’s weight in the present study". This contradicts the data in Table 1, where shell weight is shown to be between 9.42% and 9.99%.

3. The Discussion claims there was a significant improvement (p≤0.05) in albumen weight with increased egg size, but Table 1 shows this effect was not significant (p=0.889).

4. The Methods section describes a finisher diet for days 29-41, but the study itself concluded at day 35.

5. The egg weights reported for the quality assessment in Table 1 (S=60.25g, M=65.10g, L=70.07g) are slightly different from the weights for the eggs set for incubation in Table 2 (S=60.03g, M=65.01g, L=70.01g). 

6. The description of the chick yield calculation in the Methods section is incorrect. It is stated as "(egg weight / chick weight) x 100", which is the inverse of the correct formula, (chick weight / egg weight) x 100, which is properly noted in the footnote of Table 2.

7. The Discussion section states that "shape index values were decreased during early, mid and late stage of production cycle". However, the study was only conducted at the mid-stage (45th week) and provides no data for early or late stages.

8. The Methods section states that 10 eggs were used for quality measures, but later text implies 10 eggs from each of the three groups were used, which would be 30 eggs total. 

9. The housing temperature is listed as 68°F (20°C). This is unusually low for raising broiler chicks.

The authors have not responded to correspondence regarding this retraction.