Effects of in ovo feeding of vitamin C on post-hatch performance, immune status and DNA methylation-related gene expression in broiler chickens

In ovo feeding of vitamins in broilers: A comprehensive meta-analysis of hatchability and growth performance

In ovo feeding has been introduced as a cost-effective method to improve hatchability and broiler performance. Specifically, several studies have focused on the impact of vitamins. However, due to variations in experimental conditions across all trials, drawing general conclusions appears challenging. Therefore, we conducted a meta-analysis of 17 published papers, including a maximum of 134 sample size to evaluate the potential effects of in ovo feeding of vitamins in broilers. Studies were retrieved by consulting scientific repositories such as Pubmed, Scopus, Scielo, Web of Science, and Google Scholar. A binary logistic model was used to determine the parameters influencing hatchability. To assess variations in hatchling weight and growth parameters based on the vitamin category, a mixed model analysis of variance was performed, considering the study as a random effect and the vitamin category as a fixed effect. Finally, a linear mixed model was used to develop equations that explain the evolution of growth parameters based on vitamin concentration, volume, and day of injection. The results revealed that for better hatchability, it is preferable to consider heavier eggs (p = 0.007), lower volumes (p = 0.039), and late injection (p = 0.022). Vitamin E was associated with higher hatchling weight (p = 0.037), while vitamin C exhibited the lowest overall feed conversion ratio (p = 0.042). Interactions were observed between the day of injection and vitamin concentration or volume of injection for all studied growth parameters. In summary, the findings of this study suggest that hatchability during in ovo feeding is influenced by technique-related parameters, whereas growth parameters can be modulated by the category of vitamin injected. Consequently, this study lays the groundwork for future investigations assessing the effects of in ovo feeding in broilers, as it highlights the relationship between the methodology and potential outcomes.

DNA methylation in poultry: a review

As an important epigenetic modification, DNA methylation is involved in many biological processes such as animal cell differentiation, embryonic development, genomic imprinting and sex chromosome inactivation. As DNA methylation sequencing becomes more sophisticated, it becomes possible to use it to solve more zoological problems. This paper reviews the characteristics of DNA methylation, with emphasis on the research and application of DNA methylation in poultry.

Improving hydrocarbon toxicity tolerance in poultry: role of genes and antioxidants

Sustenance of smallholder poultry production as an alternative source of food security and income is imperative in communities exposed to hydrocarbon pollution. Exposure to hydrocarbon pollutants causes disruption of homeostasis, thereby compromising the genetic potential of the birds. Oxidative stress-mediated dysfunction of the cellular membrane is a contributing factor in the mechanism of hydrocarbon toxicity. Epidemiological studies show that tolerance to hydrocarbon exposure may be caused by the activation of genes that control disease defense pathways like aryl hydrocarbon receptor (AhR) and nuclear factor erythroid 2p45-related factor 2 (Nrf2). Disparity in the mechanism and level of tolerance to hydrocarbon fragments among species may exist and may result in variations in gene expression within individuals of the same species upon exposure. Genomic variability is critical for adaptation and serves as a survival mechanism in response to environmental pollutants. Understanding the interplay of diverse genetic mechanisms in relation to environmental influences is important for exploiting the differences in various genetic variants. Protection against pollutant-induced physiological responses using dietary antioxidants can mitigate homeostasis disruptions. Such intervention may initiate epigenetic modulation relevant to gene expression of hydrocarbon tolerance, enhancing productivity, and possibly future development of hydrocarbon-tolerant breeds.

Physiological effects of in ovo delivery of bioactive substances in broiler chickens

The poultry industry has improved genetics, nutrition, and management practices, resulting in fast-growing chickens; however, disturbances during embryonic development may affect the entire production cycle and cause irreversible losses to broiler chicken producers. The most crucial time in the chicks' development appears to be the perinatal period, which encompasses the last few days of pre-hatch and the first few days of post-hatch. During this critical period, intestinal development occurs rapidly, and the chicks undergo a metabolic and physiological shift from the utilization of egg nutrients to exogenous feed. However, the nutrient reserve of the egg yolk may not be enough to sustain the late stage of embryonic development and provide energy for the hatching process. In addition, modern hatchery practices cause a delay in access to feed immediately post-hatch, and this can potentially affect the intestinal microbiome, health, development, and growth of the chickens. Development of the in ovo technology allowing for the delivery of bioactive substances into chicken embryos during their development represents a way to accommodate the perinatal period, late embryo development, and post-hatch growth. Many bioactive substances have been delivered through the in ovo technology, including carbohydrates, amino acids, hormones, prebiotics, probiotics and synbiotics, antibodies, immunostimulants, minerals, and microorganisms with a variety of physiological effects. In this review, we focused on the physiological effects of the in ovo delivery of these substances, including their effects on embryo development, gastrointestinal tract function and health, nutrient digestion, immune system development and function, bone development, overall growth performance, muscle development and meat quality, gastrointestinal tract microbiota development, heat stress response, pathogens exclusion, and birds metabolism, as well as transcriptome and proteome. We believe that this method is widely underestimated and underused by the poultry industry.

Effects of the In Ovo Administration of L-ascorbic Acid on the Performance and Incidence of Corneal Erosion in Ross 708 Broilers Subjected to Elevated Levels of Atmospheric Ammonia

Effects of the in ovo injection of various levels of L-ascorbic acid (L-AA) on the performance and corneal erosion incidence in Ross 708 broilers exposed to 50 parts per million (ppm) of atmospheric ammonia (NH₃) after hatch were determined. A total of 1440 Ross 708 broiler embryos were randomly assigned to 4 treatments: non-injected (control), 0.85% sterile saline-injected (control), or saline containing 12 or 25 mg of L-AA. At hatch, 12 male chicks were randomly assigned to each of 48 battery cages with 12 replicate cages randomly assigned to each treatment group. All birds were exposed to 50 ppm of NH₃ for 35 d and the concentration of NH₃ in the battery cage house was recorded every 20 s. Mortality was determined daily, and mean body weight (BW), BW gain (BWG), average daily BW gain (ADG), and feed intake, as well as feed conversion ratio (FCR), were determined weekly. From 0 to 35 d of post-hatch age (doa), six birds from each cage were selected and sampled for eye erosion scoring. Incidences of corneal erosion were significantly higher at 21 and 28 doa in comparison to those at 14 and 35 doa, and at 21 doa, birds in the saline-injected group exhibited a higher incidence of corneal erosion compared to all other treatment groups. The in ovo injection of 12 mg of L-AA increased BWG (p = 0.043) and ADG (p = 0.041), and decreased FCR (p = 0.043) from 0 to 28 doa in comparison to saline-injected controls. In conclusion the in ovo administration of 12 mg of L-AA may have the potential to improve the live performance of broilers chronically exposed to high aerial NH₃ concentrations, but further study is needed to determine the physiological and immunological factors that may contribute to this improvement.

Effect of In Ovo Vitamin C Injection against Mobile Phone Radiation on Post-Hatch Performance of Broiler Chicks

This study aimed to investigate the effect of in ovo injection of vitamin C to reduce the harmful effects of electromagnetic waves (EMWs) emitted from mobile phones on chicken embryos. In this study, a total of 750 fertilized eggs of Ross 308 were exposed to EMWs for 1050 min during the incubation period. On the 17th day of incubation, the eggs were divided into three groups and solutions were injected into the amnion sac of embryos. The chicks were housed separately in accordance with in ovo treatments for 5 wk after hatching. An in ovo vitamin C injection resulted in a lower hatching weight. The post-hatch mortality or production efficiency factor of birds in the in ovo vitamin C injection group and the intact egg group were comparable, and were better than that of the other negative control group. In ovo vitamin C injection in eggs subjected to EMWs significantly increased their body weight gain, carcass weight, abdominal fat weight, and AST levels, but reduced spleen weight and PON-1 levels. In conclusion, an in ovo vitamin C injection in eggs subject to mobile phone EMWs improved the post-hatch performance of chicks, but low PON and high AST activities indicate an increase in oxidative damage among broiler chicks.

Effects of the In Ovo and Dietary Supplementation of L-Ascorbic Acid on the Growth Performance, Inflammatory Response, and Eye L-Ascorbic Acid Concentrations in Ross 708 Broiler Chickens

Simple Summary

L-ascorbic acid (L-AA), known as vitamin C, is involved in several metabolic process, including bone formation, antioxidant activity, and inflammatory response. It is well documented that the antioxidant capacity and immunity of broilers are enhanced in response to the dietary or in ovo administration of L-AA. The aim of the current study was to determine the effects the in ovo or dietary administration of L-AA on the post hatch performance, plasma nitric oxide, and eye L-AA concentrations of Ross 708 broilers. At 17 days of incubation, the following treatments were administered: non-injected or sham-injected (100 μL of saline) controls, or the injection of either 12 or 25 mg of L-AA suspended in 100 μL of saline. In addition, chicks were fed a commercial diet with or without 200 mg/kg of supplemental L-AA. The results of the current study revealed that the eye concentrations of L-AA were higher in males in comparison to females. Additionally, 12 mg of L-AA decreased plasma nitric oxide levels in 14-day-old male broilers in comparison to all the other in ovo injection treatment groups. Compared to a commercial diet, dietary L-AA lowered feed conversion ratio during the second week of post hatch growth. In conclusion, the in ovo administration of L-AA was more effective in reducing inflammatory response, whereas the dietary source had a greater impact on the live performance of broilers. Further research is needed to determine the aforementioned effects throughout the entire growing phase.

Abstract

Effects of the dietary and in ovo administration of L-ascorbic acid (L-AA) on the performance, plasma nitric oxide, and eye L-AA concentrations of Ross 708 broilers were investigated. At 17 days of incubation, live embryonated hatching eggs were randomly assigned to a non-injected or sham-injected (100 μL of saline) control group, or a group injected with either 12 or 25 mg of L-AA suspended in 100 μL of saline. Chicks received a commercial diet with or without 200 mg/kg of supplemental L-AA and were randomly assigned to each of 6 replicate floor pens in each in ovo injection-dietary treatment combination. Weekly live performance variables through 14 days of post hatch age (doa) and the eye weights in both sexes at 0, 7, and 14 doa were determined. At 0 and 14 doa, plasma nitric oxide levels and eye L-AA concentrations of one bird of each sex in each pen were determined. Dietary supplemental L-AA decreased feed intake and growth between 0 and 7 doa, but from 8 to 14 doa; all birds fed supplemental L-AA had a lower feed conversion ratio. At 14 doa, male chicks had higher eye L-AA concentrations and lower plasma nitric oxide levels when treated in ovo with 12 mg of L-AA. In conclusion, dietary L-AA may be used to improve feed conversion in the second week of broiler post hatch growth. However, the in ovo administration of 12 mg of L-AA can increase male eye L-AA concentrations and is effective in reducing their general inflammatory response.

In ovo Feeding as a Tool for Improving Performance and Gut Health of Poultry: A Review

Early growth and development of the gastrointestinal tract are of critical importance to enhance nutrients' utilization and optimize the growth of poultry. In the current production system, chicks do not have access to feed for about 48-72 h during transportation between hatchery and production farms. This lag time affects early nutrient intake, natural exposure to the microbiome, and the initiation of beneficial stimulation of the immune system of chicks. In ovo feeding can provide early nutrients and additives to embryos, stimulate gut microflora, and mitigate the adverse effects of starvation during pre-and post-hatch periods. Depending on the interests, the compounds are delivered to the embryo either around day 12 or 17 to 18 of incubation and via air sac or amnion. In ovo applications of bioactive compounds like vaccines, nutrients, antibiotics, prebiotics, probiotics, synbiotics, creatine, follistatin, L-carnitine, CpG oligodeoxynucleotide, growth hormone, polyclonal antimyostatin antibody, peptide YY, and insulin-like growth factor-1 have been studied. These compounds affect hatchability, body weight at hatch, physiological functions, immune responses, gut morphology, gut microbiome, production performance, and overall health of birds. However, the route, dose, method, and time of in ovo injection and host factors can cause variation, and thereby inconsistencies in results. Studies using this method have manifested the benefits of injection of different single bioactive compounds. But for excelling in poultry production, researchers should precisely know the proper route and time of injection, optimum dose, and effective combination of different compounds. This review paper will provide an insight into current practices and available findings related to in ovo feeding on performance and health parameters of poultry, along with challenges and future perspectives of this technique.

In ovo feeding of vitamin C regulates splenic development through purine nucleotide metabolism and induction of apoptosis in broiler chickens

Nutrition in early life has a long-term influence on later health. In order to the explore effects of in ovo feeding (IOF) of vitamin C on splenic development, splenic metabolism and apoptosis were detected in embryo, adult chickens and in vitro. A total of 360 fertile eggs were selected and randomly assigned to control (CON) and vitamin C (VC) groups which were injected with saline and vitamin C on embryonic day 11, respectively. Functional enrichment of differentially expressed genes by transcriptome on embryonic day 19 suggested that purine nucleotide metabolism might be a potential pathway for the IOF of vitamin C to regulate spleen development. Additionally, the IOF of vitamin C significantly increased splenic vitamin C content on post-hatch day 21. Meanwhile, the splenic expression of adenosine deaminase, serine/threonine kinase 1 and proliferating cell nuclear antigen was down-regulated, whereas the expression of cysteinyl aspartate specific proteinase 9 was up-regulated in the VC group. On post-hatch day 42, the IOF of vitamin C significantly down-regulated the splenic expression of B-cell lymphoma 2 and increased the mRNA level of cysteinyl aspartate specific proteinase 9. The IOF of vitamin C could regulate the expression of genes related to adenylate metabolism and increased the apoptosis rate in vitro, which is consistent with the result in vivo. In conclusion, the IOF of vitamin C regulated splenic development and maturation by affecting purine nucleotide metabolism pathway and promoting apoptosis.

Exploring the effectiveness of in ovo feeding of vitamin C based on the embryonic vitamin C synthesis and absorption in broiler chickens

BACKGROUND

Many researches about in ovo feeding (IOF) of vitamin C (VC) are gradually carried out to explore physiological development in chicken, but little studies focus on VC synthesis capacity of the embryo itself, the selection of injection site and the effectiveness of IOF of VC. This study aims to explore the above problems.

RESULTS

Kidney and yolk sac were the main organs for VC synthesis and L-gulonolactone oxidase (GLO) expression was lower during pre-hatch development than that during post-hatch development. Sodium-dependent vitamin C transporter 1 (SVCT1) expression was increased continuously in yolk sac from embryonic age 19 (E19) to post-hatch day 1 (D1) and in intestine (duodenum, jejunum and ileum) from E17 to D1. Plasma VC content was higher at D1 than that at D21 and D42. IOF of VC significantly reduced GLO expression in liver, kidney and yolk sac as well as SVCT1 expression in duodenum, jejunum and ileum, but increased the VC content in plasma, brain, kidney and liver. In addition, IOF of VC obviously reduced the embryonic morality and increased the hatchability under heat stress.

CONCLUSIONS

This study suggested that IOF of VC at E11 in yolk was effective for embryonic VC supplementation. These findings provide a theoretical reference about the method of embryonic VC supplementation and effective methodology on embryonic VC nutrition in broiler chickens.

The effect of selected in ovo green light photostimulation periods on post-hatch broiler growth and somatotropic axis activity

Targeted in ovo green light (GL) photostimulation during the last days of broiler egg incubation increases embryonic expression of the somatotropic axis, similar to in ovo green light photostimulation from embryonic day (ED) 0 to the end of incubation. The aim of this study was to examine the effect of selected in ovo GL photostimulation periods on post-hatch broiler growth. Four hundred twenty fertile broiler eggs were divided into 7 treatment groups: the first incubated in the dark (standard conditions) as a negative control; the second incubated under monochromatic GL from ED0-ED20 (positive control); the third group incubated under monochromatic GL light from ED15-ED20; the fourth, fifth and sixth groups were incubated under monochromatic GL on ED16, ED17, and ED18, respectively; and the seventh group was incubated under monochromatic GL from ED18-ED20. All illumination was provided intermittently using LED lamps. After hatch, all chicks were transferred to a controlled room under standard rearing conditions. The group incubated under green light from ED18 until hatch showed similar results to the positive control group in body weights, as well as breast muscle weights (as % of body weights), and an elevation in the somatotropic axis activity during the experiment. We suggest that broiler embryos can be exposed to in ovo GL photostimulation from ED18 until hatch (hatching period), and still exhibit the same performance as obtained by photostimulation from d 0 of incubation.