Effects of Short Periods of Incubation During Egg Storage (SPIDES) in Prolonged Stored Eggs of Late DeKalb Breeder on Hatchability, Embryonic Mortality and Chick Quality

INTRODUCTION

The storage of hatching eggs is a common routine in hatcheries and varying in duration depending on hatchery capacity and the demand of day old chicks (Gharib, 2013). In some cases, the need of extending the period of storage more than seven days may takes place. Hatching eggs are stored, generally, to minimize transport cost or to collect enough eggs for high capacity incubators. Egg storage for more than 7 days deteriorated the egg white, increased embryonic mortality and chicks’ abnormalities (Van de Ven, 2004) reduced hatchability percentage and post-hatch performance (Petek and Dikmen, 2006; Ruiz and Lunam, 2002; Tona et al., 2003). It is also responsible for impairing embryo development and livability with a lag in embryo development due to change of metabolism rate (Christensen et al., 2001; Elibol et al, 2002; Fasenko and O’Dea., 2009), and decline in hatchability (Yassin etal., 2008). Many studies have been applied to enhance the hatching of eggs storedmore than 7 days. Many suggested methods to modify the eggs storage conditions in order to prolong the period in which they maintain their high ability to hatch well. Pre-incubation (PI), i.e., temporary warming of eggs, which is supposed to imitate the natural conditions that the birds provide to the eggs before they start to hatch, turned out to be the most effective method (Fasenko et al., (2001a, b) and demonstrated that a single (PI) allows the embryos to finish the formation of hypoblasts, which increases the ability of hatching up to 14 d of eggs storage. Dymond et al., (2013) modified this method by analyzing an effect of short periods of incubation during egg storage (SPIDES). The most promised one is to warm eggs before or during storage (Anonymous, 2000). Warming of eggs before storage has been reported to increase hatchability and reduce embryonic mortality (Fasenko et al., 2001ab). The objective of this study is to illustrate the role of (SPIDES) (60 and 120 minutes) of eggs during egg storage (4, 9, and 14days) and flock age (75, 80, and 85 weeks) on subsequent hatchability traits.

MATERIALS AND METHODS

Experimental design

The experiment was conducted at a hatchery unit of Coral Company for Feed and Chicks Production. A total of 810 fertile eggs, clean and without shell abnormalities from DeKalb White layer breeder flock at different ages (75, 80, and 85 weeks) were randomly selected and transported to the hatchery in three groups (270 eggs each). Each group was distributed in a 3 x 3 x 3 factorial arrangement in a complete randomized design, with three daily warming durations (SPIDES) (0, 60 and 120 minutes) at 37.5°C and 53% RH), age (75, 80, and 85 weeks) and three storage periods (4, 9 and 14 days 18° C and 75%) summing up twenty-seven treatments with three replicates ten eggs each placed in setting trays.

General management

Eggs were collected three times a day and transported to the hatchery and immediately disinfected by simple fumigation with 3.2g paraformaldehyde⁄m3 area for 20 minutes heated in an electric pan to 105°C in the fumigation room at 25°C and relative humidity 70%. After disinfection the room was ventilated with fresh air for 1.5 hrs to remove the fumigation residues. Hatching eggs in the control (0 minutes) were kept in the cooler at 18°C and relative humidity 75% during the entire storage period. The two treatments were placed in a setter (Pas Reform, type Corridor 57, 2002, Zeddam) operating at 37.5°C and 53% RH, removed after 60 and 120 minutes daily warming and transferred to the egg storage room. This protocol was repeated on the three storage periods (4, 9 and 14 days). After 4, 9 and 14 days of storage period the eggs were set in a setter (Pas Reform, type Corridor 57, 2002, Zeddam) at 37.5°C average temperature and 53% RH, eggs were hourly turned for 18 days using single stage incubation program of layer eggs. At day 18 of incubation, hatching eggs (HE) were candled and consequently the clear eggs were removed and opened to determine macroscopically infertile or stage of embryonic mortality to calculate true fertility. After candling, HE with living embryos were transferred to the hatchery baskets and were placed in the hatcher cabinets (Pas Reform, Tiros, 2002, Zeddam) in which the temperature and relative humidity were adjusted at 36.6°C and 75% RH.

Measured parameters:

At the end of the hatching process hatched chicks and pipped eggs were removed and counted. All chicks were classified as first or second grade chicks based on the physical parameters. A chick was classified as a first grade chick if it was clean, dry, free of deformities or lesions and had bright eyes. The other chicks were classified as second grade chicks. The remaining unhatched eggs were broken to determine the late stage of embryonic mortality. At 18 and 21 day of incubation the following periods and phases of embryonic mortality were used to classify the dead embryos. The main characteristics observed in the current study based on description of Tona et al., (2004) who reported them as follows:

Days 1 – 7 (white membrane over the yolk, blood ring).

Days 8 – 14 (black eye visible, embryo without down).

Days 15 – 21 (small embryo with down, full grown embryo with yolk out or full grown dead embryo).

The fertility, hatchability and mortality records were reported according to (Erensayin, 2002) as follows:

True Fertility (%) = Number of fertile eggs ⁄ total number of eggs set X100 Hatchability eggs set (%) = Number of chicks hatched ⁄ total number of eggs set X 100

Hatchability of fertile eggs (%) = Number of chicks hatched ⁄ total number of fertile eggs X100

Early phase mortality (%) = Number of embryos dead in early phase/number of unhatched eggs X100

Middle phase mortality (%) = Number of embryos dead in middle phase/number of unhatched eggs X100

Late phase mortality (%) = Number of embryos dead in late phase/number of unhatched eggs ×100

First grade chicks (%) = Number of first grade chicks ⁄number of chicks hatched×100 Second grade chicks (%) = Number of second grade chicks ⁄number of chicks hatched×100

Statistical analysis

Data were subjected to ANOVA using the General Linear Model procedure of SPSS (2008). Duncan’s multiple range test used to assess the significant differences among treatment means according to the method described by (Steel et al., 1996).

RESULTS AND DISCUSSION

Effect of Short period incubation during storage (SPIDES) treatment, breeder’s age and storage period on embryonic mortality

Early death, mid death, late death and total embryonic mortality percentages were significantly influenced by the experimental treatments (Table 1). Short period incubation (SPIDES) treatment for (60 minutes) resulted in significantly (P ≤ 0.01) the lowest percentages of early, late and total embryonic mortality when compared with the other short period incubation (120 minutes) or (zero minutes) group, while Mid death was not influenced by the (SPIDES) treatment. Early death, late death and total embryonic mortality percentages were significantly (P ≤ 0.01) increased by breeder’s age, while no significant effect in mid death. Four days of storage period resulted in significantly (P ≤ 0.01) reduction in early death and total embryonic mortality followed by nine. Mid death results showed a significant (P ≤ 0.05) reduction for eggs stored for four days compared to nine and fourteen days of storage period. Late death was not influenced by the storage period. The reduction in embryonic viability during egg storage is due to the apoptosis (cell death) in the egg (Bakst, 2016). Until seven days of proper egg storage, the number of embryonic cells remains stable, then after seven days, the number of dead and abnormal cells started to increase. Maintaining lower temperature and higher humidity during egg storage can dramatically improve cell viability for eggs to be stored long term (Fasenko, 2007). Similar findings w reported by Gharib (2013) who found that significantly higher rate of late embryonic mortality for egg stored for10 and 14 d compared to 4 and 7 d of storage. Hamidu etal., (2011) explained the deleterious effect of prolonged storage on broiler and layerblast dermal cell viability, cell death and embryo survival. Significant interactions were also detected between the SPIDES treatment duration and storage period on all embryonic mortality rates (Table 2). The results indicated that SPIDES treatment for 60 minutes significantly decreased embryonic mortality within all storage periods as compared to those not warmed or warmed for 120 minutes at 75, 80 and 85 week of age breeder’s eggs respectively except for mid death which showed no significant differences. When eggs were stored for more than four days, total embryonic mortality rates were significantly lower when eggs were exposed to SPIDES treatment for 60 minutes, as compared to those not heated or heated for 120 minutes at 75, 80 and 85 weeks old breeder’s eggs respectively. These results are in agreement with the previous reports on broilers, turkey and Japanese quail chicks (Anonymous, 2000; Fasenko etal., 2001a, b) warming eggs before or during storage was reported to increasehatchability and reduce embryonic mortality. Tag EL -Din, et al., (2017) recommended that when storage of eggs to more than seven days, one should warm eggs for 2.5 h every five days to minimize the harmful impact of storage. These results are in agreement with the present study. Reijrink et al., (2010) reported that significantly higher late embryonic mortality rate observed for egg stored for 10 and 14 d compared to 4 and 7 d storage.

Effect of Short period incubation during storage (SPIDES), breeder’s age and storage period on fertility and hatchability:

The results of the true fertility, hatchability of total and fertile eggs were shown in Table 3. There were no significant effects of Short period incubation (SPIDES) treatment for (0, 60 and 120 minutes), storage period (4, 9 and 14 days) on the true fertility percentage. Storage heating eggs did not affect apparent fertility. Fertility should not have been affected by the two main treatments because fertilization would or would not have occurred before the eggs were exposed to the treatments. Similar suggestions were reported by Fasenko et al., (2001a) in chicken eggs, and Petek and Dikmen (2004) in quail eggs. They found that the differences for the apparent fertility among the main groups of pre-storage heating and storage duration were not significant. On the other hand, true fertility percentage was significantly (P ≤ 0.01) affected due to breeder’s age. The highest values obtained from eggs produced by 75 weeks old breeders followed by eggs produced from 80 weeks old breeders and the lowest values obtained from eggs produced from 85 week old breeders. True fertility percentage was not affected by the all interactions between factors. These results are in agreement with those reported by Fasenko et al., (2001) who showed that fertility of broiler breeder eggs was not affected by the interaction as fertilization would or would have not occurred before the eggs were exposed to the pre-storage incubation (0, 12 or 18 hrs) or by storage periods (4 or 14 days). Similarly, Elibol et al., (2002) did not find any significant effects on the apparent fertility when they stored eggs for four, seven, ten and fourteen days at 18°C and 75% RH. Pre-warming treatment did not show any significant effect on the number of fertile eggs and fertility%.

Hatchability of fertile and total eggs was significantly (P ≤ 0.01) affected by the experimental factors. The results showed that higher percentages of both hatchability of fertile or total eggs set were observed for groups exposed to short period incubation (SPIDES) treatment for 60 minutes followed by those SPIDES for 120 minutes and the poorest values observed for control group (0 minutes). The highest values for the two parameters obtained from eggs produced by 75 weeks old breeders followed by those produced by 80 weeks old breeders and the lowest values obtained from eggs produced from 85 week old breeders. Longer period of egg storage resulted in a linear significant decrease in the hatchability of fertile and total eggs. A significant (P ≤ 0.01) improvement in hatchability from total eggs and hatchability from fertile eggs was observed for eggs stored for 4 days followed by those eggs stored for 9 days and the lowest values stand for eggs stored for 14 days. The interaction between SPIDES treatment (minutes) and storage period days showed a highly significant (P ≤ 0.01) effect on both hatchability on fertile and total eggs. SPIDES treatment for 60 minutes significantly increased hatchability in eggs stored for more than 4 days as compared to those not heated or heated for 120 minutes at 75, 80 and 85 week of old breeder’s eggs respectively (Table 4). Lower rates of fertilization, hatchability, and higher embryonic mortality at various incubation periods of older hens’ eggs are caused by a number of biological factors such as decreased sperm retention in the uterovaginal sperm host glands (Fasenko et al., 1992) and deteriorating egg quality (Reijrink et al., 2008). In this study, short period incubation during storage (SPIDES) treatment for 60 minutes for 4 days of eggs storage allowed for an improvement of hatchability, mainly from eggs of older hens and may be considered as a good practice to improve incubation results of eggs stored for short, intermediate, and long periods. These results are consistent with previous reports by Reijrink et al., (2010), who improved hatching from eggs from older hens stored for 11 d and treated with PI. Short period of incubation during storage (SPIDES) treatment for 60 minutes may be considered as a good practice to improve incubation results of eggs stored for short, intermediate, and long periods. Tag EL-Din et al., (2017) reported that warming egg at 2.5 and 5 hours showed the highest hatchability from total eggs and hatchability from fertile eggs. In further contrast to previous studies by Fasenko et al., (2001b) and Reijrink et al., (2009) found a positive effect on hatchability when advancing SPIDES embryos to early primitive streak formation over several short pre-incubation, advancement of embryos to hypoblast formation or primitive streak formation in 6- or 12-h pre-incubation, respectively, showed a detrimental effect. Dymond et al., (2013) have shown that three-to-four ‘short periods of incubation during egg storage’ or ‘SPIDES’ of 21 days increased hatchability and reduced hatching time when compared with eggs stored for similar periods of 21 days (controls). These findings are in agreement with Damaziak et al., (2018) who demonstrated that the 2 × 4 h pre-incubation during 12 d of eggs storage allowed for an improvement of hatchability, mainly from eggs of older hens.

Effect of Short period incubation during storage (SPIDES) treatment, breeder’s age and storage period on chick quality:

Commercial chick quality grading was used for measuring the chick quality. Chick quality grade studied were significantly (P ≤ 0.01) affected by short period incubation (SPIDES) treatment for (0, 60 and 120 minutes), breeder’s age (75, 80 and 85week) and storage period (4, 9 and 14 days) (Table 5). Short period incubation (SPIDES) treatment for 60 minutes resulted in significant (P ≤ 0.01) improvement in both chick quality grades followed by short period incubation (SPIDES) treatment for 120 minutes, as compared to non-heated eggs. Breeder’s age significantly (P ≤ 0.01) affected the chick quality. Chicks produced from 85 weeks of age breeders were significantly (P ≤ 0.01) lower in quality (lower percentage of first grade chicks and higher percentage of second grade chicks) compared to those chicks hatched from 75 and 80 week of age of breeders. No significant differences between chicks hatched from 75 and 80 weeks of age breeders. Long storage period 14 days resulted in significant (P ≤ 0.01) lower quality hatched chicks compared to those hatched from eggs stored for 4 or 9 days. No significant differences in chick’s quality between chicks hatched from eggs stored for 4 or 9 days. Longer periods of storage affected the vitality of the embryo, causing increased early and late embryonic mortality, a delay in hatch and reduced chick quality (Fasenko, 2007; Dymond, 2013). There were significant interactions between the storage period and SPIDES treatment duration for chicks' grade (Table 6). The obtained data indicated that the chicks produced from SPIDES treatment for 60 minutes and stored for 4, 9 and14 days had significantly higher percentages of grade (A) chicks, as compared to non-warmed eggs at 75, 80 and 85 week old breeder’s eggs respectively (Table 3). Tag EL-Din, et al., (2017) reported that warming egg at 2.5 and 5 hours showed highest significance for chick quality. Damaziak et al., (2018) showed that pre incubation had increased the hatchability of the set and apparently fertilized eggs, decreased the number of unhatched eggs, and improved chick’s quality.

In conclusion, short periods of incubation during egg storage daily for 4- 9 days of late DeKalb breeder’s (75-80 weeks) hatching eggs for 60- 120 minutes at 37.5° C and 53% RH could be used by the poultry industry as a method to improve hatchability, decrease embryonic mortality percentage and increase the number of saleable first grade chicks which by far increases profits of eggs store for longer periods.

Table 1. Effect of short period of incubation during storage (SPIDES), breeder’s age and storage period on embryonic mortality

Table 2. Interaction effects of short period of incubation during storage (SPIDES), breeder’s age and storage period on embryonic mortality (%)

Effects of Short Periods of Incubation During Egg Storage (SPIDES) in Prolonged Stored Eggs of Late DeKalb Breeder on Hatchability, Embryonic Mortality and Chick Quality - Image 1

Click here to enlarge the image

Table 3. Effect of short period of incubation during storage (SPIDES), breeder’s age and storage period on fertility and hatchability percentage

Table 4. Interaction effects of short period of incubation during storage (SPIDES), breeder’s age and storage period on fertility and hatchability percentage

Click here to enlarge the image

Table 5. Effect of short period of incubation during storage (SPIDES), breeder’s age and storage period on chick quality

Table 6. Interaction effect of short period of incubation during storage (SPIDES), breeder’s age and storage period on chick quality

This article was originally published in Global Journal of Animal Scientific Research, 8(2), 68-82. http://www.gjasr.com/index.php/GJASR/article/view/49.