Incubation Of Chicken Eggs Research Articles

Exploratory Study of Sex Identification for Chicken Embryos Based on Blood Vessel Images and Deep Learning

The identification of a chicken’s sex is a massive task in the poultry industry. To solve the problems of traditional artificial observation in determining sex, such as time-consuming and laborious, a sex identification method of chicken embryos based on blood vessel images and deep learning was preliminarily investigated. In this study, we designed an image acquisition platform to capture clear blood vessel images with a black background. 19,748 images of 3024 Jingfen No. 6 breeding eggs were collected from days 3 to 5 of incubation in Beijing Huadu Yukou Poultry Industry. Sixteen thousand seven hundred sixty-one images were filtered via color sexing in 1-day-old chicks and constructed the dataset of this study. A sex identification model was proposed based on an improved YOLOv7 deep learning algorithm. An attention mechanism CBAM was introduced for YOLOv7 to improve the accuracy of sex identification of chicken eggs; the BiFPN feature fusion was used in the neck network of YOLOv7 to fuse the low-level and high-level features efficiently; and α-CIOU was used as the bounding box loss function to accelerate regression prediction and improve the positioning accuracy of the bounding box of the model. Results showed that the mean average precision (mAP) of 88.79% was achieved by modeling with the blood vessel data on day 4 of incubation of chicken eggs, with the male and female reaching 87.91% and 89.67%. Compared with the original YOLOv7 network, the mAP of the improved model was increased by 3.46%. The comparison of target detection model results showed that the mAP of our method was 32.49%, 17.17%, and 5.96% higher than that of SSD, Faster R-CNN, and YOLOv5, respectively. The average image processing time was 0.023 s. Our study indicates that using blood vessel images and deep learning has great potential applications in the sex identification of chicken embryos.

Light-dark rhythms during incubation of broiler chicken embryos and their effects on embryonic and post hatch leg bone development.

There are indications that lighting schedules applied during incubation can affect leg health at hatching and during rearing. The current experiment studied effects of lighting schedule: continuous light (24L), 12 hours of light, followed by 12 hours of darkness (12L:12D), or continuous darkness (24D) throughout incubation of broiler chicken eggs on the development and strength of leg bones, and the role of selected hormones in bone development. In the tibiatarsus and femur, growth and ossification during incubation and size and microstructure at day (D)0, D21, and D35 post hatching were measured. Plasma melatonin, growth hormone, and IGF-I were determined perinatally. Incidence of tibial dyschondroplasia, a leg pathology resulting from poor ossification at the bone’s epiphyseal plates, was determined at slaughter on D35. 24L resulted in lower embryonic ossification at embryonic day (E)13 and E14, and lower femur length, and lower tibiatarsus weight, length, cortical area, second moment of area around the minor axis, and mean cortical thickness at hatching on D0 compared to 12L:12D especially. Results were long term, with lower femur weight and tibiatarsus length, cortical and medullary area of the tibiatarsus, and second moment of area around the minor axis, and a higher incidence of tibial dyschondroplasia for 24L. Growth hormone at D0 was higher for 24D than for 12L:12D, with 24L intermediate, but plasma melatonin and IGF-I did not differ between treatments, and the role of plasma melatonin, IGF-I, and growth hormone in this process was therefore not clear. To conclude, in the current experiment, 24L during incubation of chicken eggs had a detrimental effect on embryonic leg bone development and later life leg bone strength compared to 24D and 12L:12D, while the light-dark rhythm of 12L:12D may have a stimulating effect on leg health.

Cardiac Enlargement in the Chick Embryo Induced by Hypothermic Incubation Is Due to a Combination of Hyperplasia and Hypertrophy of Cardiomyocytes

Hypothermic incubation of chicken eggs leads to smaller embryos with enlarged hearts, originally described as hypertrophic. Over the years, however, accumulated evidence suggested that hyperplasia, rather than hypertrophy, is the predominant mechanism of cardiac growth during the prenatal period. We have thus set to re-evaluate the hypothermia model to precise the exact cellular mechanism behind cardiac enlargement. Fertilized chicken eggs were incubated at either 37.5 °C (normothermia) or 33.5 °C from embryonic day (ED) 13 onward (hypothermia). Sampling was performed at ED17, at which point wet embryo and heart weight were recorded, and the hearts were submitted to histological examination. In agreement with previous results, the hypothermic embryos were 29% smaller and had hearts 18% larger, translating into a 67% increase in the heart to body weight ratio (P < 0.05 for all parameters). The cell size was essentially the same between control and hypothermic hearts in all regions analysed. Likewise, there was no significant relationship between the cell size and heart weight; however, in the hypothermic hearts, there was a trend showing positive correlation between cell sizes in different cardiac regions and heart weight. Proliferation rate, determined on the basis of anti-phosphohistone H3 immunofluorescence, showed an overall increase in the hypothermic group, reaching statistical significance (P = 0.02, t-test) in the right ventricle. The proliferation rate was similar among different regions of the same heart. However, the correlation between the proliferation rate and heart weight was only small (r2 = 0.007 and r2 = 0.234 for the normothermic and hypothermic group, respectively). We thus conclude that hyperplasia is the predominant response mechanism in this volume-overload model; mechanistically, decreased heart rate at lower temperature increases the end-diastolic and stroke volume, minimizing the drop in cardiac output through the Frank- Starling mechanism.

Effect of Green Light on Nitric Oxide Metabolism in Chick Embryos. A Possible Physiological Role.

The exposure to green light, which serves as a well-known activating factor for myogenesis during incubation of chicken eggs, contributes to intensification of embryonic metabolism of NO. A metabolic product, nitrate, is mainly accumulated in the muscles. These data suggest that light induces a NO-dependent activation of the factor, which intensifies muscle tissue development.

Detection of oocyte perivitelline membrane-bound sperm: a tool for avian collection management.

The success and sustainability of an avian breeding programme depend on managing productive and unproductive pairs. Given that each breeding season can be of immeasurable importance, it is critical to resolve pair fertility issues quickly. Such problems are traditionally diagnosed through behavioural observations, egg lay history and hatch rates, with a decision to re-pair generally taking one or more breeding seasons. In pairs producing incubated eggs that show little or no signs of embryonic development, determining fertility is difficult. Incorporating a technique to assess sperm presence on the oocyte could, in conjunction with behaviour and other data, facilitate a more timely re-pair decision. Detection of perivitelline membrane-bound (PVM-bound) sperm verifies successful copulation, sperm production and sperm functionality. Alternatively, a lack of detectable sperm, at least in freshly laid eggs, suggests no mating, lack of sperm production/function or sperm-oviduct incompatibility. This study demonstrated PVM-bound sperm detection by Hoechst staining in fresh to 24-day-incubated exotic eggs from 39 species representing 13 orders. However, a rapid and significant time-dependent loss of detectable PVM-bound sperm was observed following incubation of chicken eggs. The PCR detection of sperm in seven species, including two bacterially infected eggs, demonstrated that this method was not as reliable as visual detection using Hoechst staining. The absence of amplicons in visually positive PVMs was presumably due to large PVM size and low sperm count, resulting in DNA concentrations too low for standard PCR detection. In summary, this study demonstrated the feasibility and limitations of using PVM-bound sperm detection as a management tool for exotic avian species. We verified that sperm presence or absence on fluorescence microscopy can aid in the differentiation of fertile from infertile eggs to assist breeding managers in making prompt decisions for pair rearrangements. This protocol is currently used to manage several breeding pairs in San Diego Zoo global avian conservation programmes.

Effect of relative humidity during incubation at a set eggshell temperature and brooding temperature posthatch on embryonic mortality and chick quality

Previous studies have shown that RH during incubation of chicken eggs influences water loss from the egg and embryonic mortality. In those studies, eggshell temperatures (EST) were not monitored or controlled. Because RH influences the egg's heat loss through evaporation, EST might have been different between RH treatments, influencing embryonic mortality and development. To eliminate the effect of EST, in the current study eggs were incubated at an EST of 37.8°C from embryonic d (E) 0 until E18 and at a high (55 to 60%) or low (30 to 35%) RH from E2 until hatch. Embryonic mortality, hatch curve, and several chick quality characteristics (length, weight, navel quality, organ weights, and DM of the yolk free body mass and yolk) were determined on E18 and at hatch. Low RH increased egg weight loss between E0 and E18 (+3.0%) and third week embryonic mortality (+3.0% of fertile eggs) and decreased hatch of fertile eggs (-2.9% of fertile eggs) compared with high RH. Hatch duration and chick quality characteristics did not differ between RH treatments. To assess the effect of RH during incubation on posthatch performance under suboptimal conditions, hatchlings were brooded at a normal (35.0°C at d 0, decreasing to 27.0°C at d 4) or cold (27.8°C at d 0, decreasing to 25.6°C at d 4) temperature until 4 d posthatch. Incubation RH and brooding temperature significantly interacted with posthatch growth but not development. Both low and high RH × cold brooding temperature resulted in lower (-6.9 and -6.0 g, respectively) BW than high RH × normal brooding temperature at 4 d of age. The cold brooding temperature resulted in lower daily feed intake (-1.3 g/chick) than the normal brooding temperature. In conclusion, incubating eggs at a low RH compared with a high RH and maintaining the EST at 37.8°C decreased hatch of fertile eggs, but had little effect on chick quality or posthatch performance.

Approaches to determine the sex prior to and after incubation of chicken eggs and of day-old chicks

Domestic chickens produce eggs that contain at almost equal proportions female and male embryos. For many centuries, domestic chickens were bred as dual-purpose birds for both egg and meat production. In contrast, commercial hybrid chickens are selected for one purpose only; either eggs or meat. Surplus day-old male chicks of the layer type are currently without significant commercial value and are at best used as food for e.g. carnivorous animals. All attempts to raise male chicks of the layer type for meat production have resulted in high consumption of feed and poor meat yield which is difficult to market at competitive prices. Ethical views alongside commercial considerations are now confronted with a serious dilemma regarding the limited and reasonable utilization of newly hatched male hybrid chicks from laying strains. An abundance of scientific and practical efforts have been made in both past and present times to detect the sex in eggs pre-incubation and in embryos as early as possible. These studies include attempts to determine the sex in eggs prior to and during incubation and in day-old chicks. Various manual and instrumental morphological, enzymatic and molecular methods were used. This paper reviews these methods and discusses their relevance for practical breeding and production purposes.

Acid–base balance in chicken embryos (Gallus domesticus) incubated under high CO2 concentrations during the first 10 days of incubation

Recent studies show the importance of differential CO2 levels during the first half of incubation of chicken eggs on embryonic and postnatal growth. However, it is not known how external higher CO2 levels affect embryonic acid-base balance. In this study, the effect of an early rise in CO2, between 25th and 96th hour of incubation to 1.5% and maintained at that level until 240 h of incubation, was investigated on air cell gases, blood gas parameters from ED10 onwards and on embryonic growth and hatching parameters. Higher external CO2 concentrations resulted in a faster acidification of albumen resulting in a faster decrease of albumen pH with development, illustrating the capacity of albumen to cope with higher environmental CO2. Moreover, PCO2 in blood was higher in CO2 incubated embryos at embryonic day 10 and 11 but without a change in blood pH. The additional increase in plasma HCO3- concentration at day 10 and 11 was responsible for buffering the higher PCO2 in CO2 incubated embryos in order to stabilize pH. However, effects of hypercapnia on blood acid-base parameters extinguished 2 days after termination of high CO2 incubation. Embryonic growth was modestly accelerated which was reflected in higher embryonic weights at day 6 and 10 and a significant earlier hatching; hatchling weights were not different between treatment groups.

Effect of BioSentry 904 and ethylenediaminetetraacetic acid-tris disinfecting during incubation of chicken eggs on microbial levels and productivity of poultry.

Proper sanitation practices and the use of efficacious disinfectants in a hatchery have an effect on chick quality. Aerosol bacterial counts, egg moisture loss, hatchability, chick quality, and broiler productivity were evaluated when egg surfaces were contaminated by immersion of each egg into a broth medium containing a field isolate of Pseudomonas aeruginosa and incubated with exposure to one of three disinfectant treatments administered by fine spray: distilled water, BioSentry 904 (904), and a 1:1 ratio of 904 and ethylenediaminetetraacetic acid (EDTA)-Tris. The aerosol bacteria levels were statistically greater on day 21 of incubation in the group treated with distilled water than in those receiving disinfectants. Overall hatch of fertile eggs and egg moisture loss were comparable among all three treatments. At 1 day of age, the chicks incubated with 904 had a statistically lower yolk sac contamination rate than those incubated with 904+EDTA-Tris or distilled water. The 2-wk mortality rates, body weights, feed conversion ratios, yolk sac weights, and yolk sac contamination rates were all similar among the three treatments.

Effects of turning duration during incubation on corticosterone and thyroid hormone levels, gas pressures in air cell, chick quality, and juvenile growth

Two peaks of embryo mortality have been identified during incubation of chicken eggs (the first and the final phases of incubation), and both are linked to egg turning. Turning in the first week enables proper formation of extra-embryonic membrane and in the final week avoids embryo malpositioning. The hatchability of the eggs, however, may depend on physiological parameters (e.g., hormone levels or gas pressures) that turning may influence to ensure proper embryo development and survival. It is not clear how long turning should continue during this second phase to ensure these conditions, but it is general practice to turn eggs until 18 d. This study describes the effects of turning chicken eggs for different durations during the last days of incubation on embryo physiological parameters that may be linked to embryo survival, hatchability, and broiler posthatch performance. Cobb eggs were incubated for 21 d under standard incubation conditions but with varying turning durations. Eggs were turned until 12, 15, or 18 d and left in a horizontal position until transferred to hatcher baskets on the 19th day. Blood samples from embryos were analyzed for corticosterone at d 15, d 18, internal pipping (IP), and hatch. Triiodothyronine (T3) and thyroxine (T4) were measured at IP and at hatch. Partial pressures of CO2 (pCO2) and O2 (PO2) in the air cell were measured at d 18 and at IP stage. Hatchability of fertile eggs, incubation duration, weights of 1-d-old chicks, chick quality, and their growth potential determined as absolute weight and relative growth (RG) to d 7 were recorded. Corticosterone levels increased in all treatments with embryo age until hatch, but there were no significant differences among treatments. Eggs turned until 18 d had higher pCO2 and lower PO2 at IP than those turned for 12 or 15 d. T3 and T4 were higher at IP in eggs turned for 18 d compared with the other two groups in which T3 and T4 were not different. T3/T4 ratio in 1-d-old chicks was also lower in eggs turned until 18 d. Incubation duration, and weights of 1-d-old chicks were similar for all treatments groups. Hatchability and percentage of high quality chicks were lower for eggs turned for 15 d compared to the 2 other groups, which were not different. However, 7-d-old weights and RG decreased with increasing duration of egg turning. We concluded that although turning until 18 d benefited hatchability and chick quality, it depressed potential posthatch performance of the chick to 7 d of age.

Vibration analysis on incubating eggs and its relation to embryonic development.

Coucke (1998) was the first to use acoustic resonance analysis to monitor embryo development in chicken eggs. He remarked that at around 100 hours of incubation, the course of the resonant frequency and damping changed abruptly in the case of fertile eggs. He also showed that these changes were related to a physiologic event during early embryonic development. The objective of our study is to monitor the course of the vibration parameters during the early incubation of chicken eggs and to relate these changes to egg and embryo characteristics. A total of 72 Hybro eggs were incubated vertically in a small incubator at standard conditions. Several egg parameters were measured before incubation. During the early stages of incubation the vibration behavior of these eggs was monitored. The time at which the damping of the vibration suddenly changed, the diameter of the eggs and their interaction were found to be significant explanatory variables in order to predict hatching time. A correlation coefficient r of 0.72 was obtained.

Effect of Hydrogen Peroxide Disinfection during Incubation of Chicken Eggs on Microbial Levels and Productivity

Hatchery sanitation has a significant impact on chick quality. The proper use of disinfectants is essential. Aerosol bacterial counts, egg moisture loss, hatchability, chick quality, and broiler productivity were measured in eggs exposed to hydrogen peroxide fogging and compared with eggs not exposed to disinfectant during the incubation period. Hydrogen peroxide was also evaluated in the presence of a severe challenge with Staphylococcus aureus-contaminated eggs. A significant reduction was found in aerosol bacterial counts within the hatcher when incubators were fogged with 3% hydrogen peroxide when compared with water-fogged machines even in the face of high bacterial challenge. Eggs exposed to hydrogen peroxide lost a significantly greater amount of moisture during incubation, but hatchability was not affected. The use of hydrogen peroxide as a hatchery sanitizer did not affect broiler livability, body weight, or feed conversion but did reduce the incidence of retained yolk sacs in 42-day-old chickens.

Incubation of chicken eggs at altitude theoretical consideration of optimal gas composition

1. Eggs from sea level which are transferred to higher altitude for incubation require changes in incubator gas composition if they are to develop normally. 2. This not only requires compensation for the reduced O2 partial pressure but, and of equal importance, recognition of the increased diffusivity of gases at altitude. 3. Equations are developed for predicting the required changes in O2, CO2 and water vapour composition of incubator gas at any altitude.

Mortality of the Turkey Embryo

THE distribution of embryo mortality in turkey eggs is not reported in the literature. In the experiment reported herein it has been determined and compared with that of the fowl. Payne (1919) found that there were two critical periods during the incubation of chicken eggs. These periods of high mortality occurred on the fourth, fifth, and sixth days and on the eighteenth, nineteenth, and twentieth days of incubation. He observed also that the critical periods coincided in natural and artificial incubation.Byerly (1930) noted the occurrence of a minor peak of mortality in chicken eggs on the seventh day of incubation, and Byerly, Titus, and Ellis (1933) found a mid-incubation peak related to nutritional deficiencies in the diet of the breeding flock. Riddle (1930) found that embryo mortality of the common pigeon, ring dove, and wild dove, when plotted on a comparable basis with that of chickens (Payne’s data) showed .