Post-hatch Performance Research Articles

Post-Hatch Performance of Broilers Following Hypoxic Exposure During Incubation Under Suboptimal Environmental Temperature.

The modern broiler is selected to exploit its full genetic potential, to sustain a rapid growth rate, and to lower the feed conversion rate (FCR). Recently reported reductions in FCR have been associated with augmented tissue formation at the expense of physiological functions such as thermoregulation. In turn, modern broilers exhibit a relatively low capability to balance energy expenditure under suboptimal ambient temperature. Hypoxic conditions at late incubation stages play a role in reforming metabolic plasticity. This work examined the effect of exposure to 12-h hypoxia (12H; 17% O2) for three consecutive days (from E16 through E18), or continuous hypoxia exposure for 48 h (48H), from E16 through E17, as compared to standard incubation (21% O2) on post-hatch performance of broilers maintained under suboptimal ambient temperatures (cold, hot, and diurnal cyclic ambient temperature). 12H chicks kept under hot ambient temperature had significantly lower body temperature (Tb) as compared to the control chicks. On day 42, both 12H and 48H chicks grown in the cyclic temperature room had significantly lower Tbs than controls. In parallel, from week 4, onward, 12H chicks had a significantly lower FCR than controls, and the 48H chicks demonstrated a lower FCR from week 5 and on. 12H and 48H broilers maintained under diurnal cyclic ambient temperature, exhibited significantly greater relative breast muscle weight, and a similar pattern was found in hypoxic broilers raised under standard and hot ambient temperatures. Hypoxic manipulation affects and create an adaptive bias in allocating metabolic energy between maintenance and growth, thus resulting in improved broiler performance, thermoregulation, and rearing under suboptimal environmental temperature.

Early posthatch body temperature, haematology and growth performance in Transylvanian naked neck chicks hatched from eggs stored for different durations

Early posthatch physiological responses and growth performances were assessed in 80 chicks hatched from Transylvanian naked neck (TN) chicken eggs stored in a cold room for 0, 3, 6, 9, and 12d before incubation with four replicates per group. The rectal temperature (RT) of birds hatched from 0 and 3d stored eggs were significantly (P < 0.01) lower than in the 9–12d storage groups. There was (P < 0.001) an increase in skin temperature on the breast (STB) as the length of storage increased. Day-old chicks and 28d-old chickens from non-stored eggs had higher (P < 0.05) packed cell volume (PCV) and haemoglobin (Hb) concentration than eggs stored for 12d. Chickens in 0, 3 and 6d storage groups had (P < 0.01) higher platelet count values than in the 12d group. During d1-28, chicks from 0 to 6d egg storage had (P < 0.001) higher weight gain and final live weight than 9–12d storage. Feed consumption was (P < 0.01) lower in 3d than in 6–12d. Chicks from 0 to 6d storage recorded a lower (P < 0.001) feed conversion ratio than in 9–12d storage. In conclusion, prolonged storage of TN eggs resulted in higher RT and STB, lower PCV and Hb, and lower growth performance during early posthatch age.

Effect of storage duration on the hatching egg quality, embryonic parameters and post-hatch performance of Cherry Valley ducks

Abstract Storage of incubating eggs is a normal and important practice after egg collection from the poultry house and often a necessity in hatchery management. However, egg storage duration and storage environmental conditions can affect egg quality and hatching parameters. The purpose of this study was to determine the effects of egg storage duration on egg quality, hatching parameters, and post-hatch performance of meat-type ducks. A total of 756 eggs were collected from a 32 weeks old breeder duck flock. Before incubation, the eggs were divided into three groups and were stored for 2, 7 or 14 d. At the end of the storage period, 7 eggs per treatment were examined to assess egg quality traits. Eggs were incubated for 28 d and hatching parameters were recorded. After hatching, the ducklings were reared according to their respective storage duration groups with 4 replicates and 15 birds per pen using a completely randomised design. Results showed that egg weight loss during storage was negatively influenced (p < 0.05) by prolonged duration. Storage of eggs for 14 days resulted in a decrease (p < 0.05) in Haugh unit and albumen weight and adversely affected embryo viability and hatchability. Extended egg storage duration did not affect (p > 0.05) egg weight loss during incubation. Embryo mortality was significantly higher (p < 0.05) for the eggs stored for 14 days. Post-hatch performance revealed that weight gain, feed conversion ratio, liver weight, and leg muscle were negatively affected (p < 0.05) by storage duration. It was concluded that the effect of egg storage duration on hatching trends in ducks are similar to that reported in chickens.

Effect of L-carnitine and high incubation temperature on pre and post hatch performance of Fayoumi chicks

Effect of L-carnitine and high incubation temperature on pre and post hatch performance of Fayoumi chicks

Chicken Incubation Conditions: Role in Embryo Development, Physiology and Adaptation to the Post-Hatch Environment.

The chicken hatching egg is a self-contained life-supporting system for the developing embryo. However, the post-hatch performance of birds depends on several factors, including the breeder management and age, egg storage conditions and duration before incubation, and the incubation conditions. Studies have determined the effect of incubation factors on chick post-hatch growth potential. Therefore, chick physical quality at hatch is receiving increasing attention. Indeed, although incubation temperature, humidity, turning and ventilation are widely investigated, the effects of several variables such as exposure of the embryo to high or low levels, time of exposure, the amplitude of variations and stage exposures on embryo development and post-hatch performance remain poorly understood. This review paper focuses on chick quality and post-hatch performance as affected by incubation conditions. Also, chick physical quality parameters are discussed in the context of the parameters for determining chick quality and the factors that may affect it. These include incubation factors such as relative humidity, temperature, turning requirements, ventilation, in ovo feeding and delay in feed access. All these factors affect chick embryo physiology and development trajectory and consequently the quality of the hatched chicks and post-hatch performance. The potential application of adapted incubation conditions for improvement of post-hatch performance up to slaughter age is also discussed. It is concluded that incubation conditions affect embryo parameters and consequently post-hatch growth differentially according to exposure time and stage of exposure. Therefore, classical physical conditions are required to improve hatchability, chick quality and post-hatch growth.

Incubation Temperature and Lighting: Effect on Embryonic Development, Post-Hatch Growth, and Adaptive Response.

During incubation, the content of the egg is converted into a chick. This process is controlled by incubation conditions, which must meet the requirements of the chick embryo to obtain the best chick quality and maximum hatchability. Incubation temperature and light are the two main factors influencing embryo development and post-hatch performance. Because chicken embryos are poikilothermic, embryo metabolic development relies on the incubation temperature, which influences the use of egg nutrients and embryo development. Incubation temperature ranging between 37 and 38°C (typically 37.5–37.8°C) optimizes hatchability. However, the temperature inside the egg called “embryo temperature” is not equal to the incubator air temperature. Moreover, embryo temperature is not constant, depending on the balance between embryonic heat production and heat transfer between the eggshell and its environment. Recently, many studies have been conducted on eggshell and/or incubation temperature to meet the needs of the embryo and to understand the embryonic requirements. Numerous studies have also demonstrated that cyclic increases in incubation temperature during the critical period of incubation could induce adaptive responses and increase the thermotolerance of chickens without affecting hatchability. Although the commercial incubation procedure does not have a constant lighting component, light during incubation can modify embryo development, physiology, and post-hatch behavior indicated by lowering stress responses and fearful behavior and improving spatial abilities and cognitive functions of chicken. Light-induced changes may be attributed to hemispheric lateralization and the entrainment of circadian rhythms in the embryo before the hatching. There is also evidence that light affects embryonic melatonin rhythms associated with body temperature regulation. The authors’ preliminary findings suggest that combining light and cyclic higher eggshell temperatures during incubation increases pineal aralkylamine N-acetyltransferase, which is a rate-limiting enzyme for melatonin hormone production. Therefore, combining light and thermal manipulation during the incubation could be a new approach to improve the resistance of broilers to heat stress. This review aims to provide an overview of studies investigating temperature and light manipulations to improve embryonic development, post-hatch growth, and adaptive stress response in chickens.

Impact of growth curve and dietary energy-to-protein ratio of broiler breeders on egg quality and egg composition

Egg characteristics have an impact on embryonic development and post-hatch performance of broilers. The impact of growth curve (GC) and dietary energy-to-protein ratio of broiler breeder hens on egg characteristics was investigated. At hatch, 1,536 pullets were randomly allotted to 24 pens in a 2 × 4 factorial dose-response design with 2 GC (standard growth curve = SGC or elevated growth curve = EGC (+ 15%)) and 4 diets, differing in energy-to-protein ratio (defined as 96%, 100%, 104% and 108% AMEn diet). Feed allocation per treatment was adapted weekly to achieve the targeted GC and to achieve pair-gain of breeders within each GC. Breeders on an EGC produced larger eggs (∆ = 2.3 g; P < 0.001) compared to breeders on a SGC. An exponential regression curve, with age (wk) of the breeders, was fitted to describe the impact of GC and dietary energy-to-protein ratio on egg composition. Yolk weight was 0.8 g higher for eggs from EGC breeders than from SGC breeders (, where was 22.1 and 22.9 for SGC and EGC, respectively; R2 = 0.97; P<0.001). An interaction between GC and dietary energy-to-protein ratio on albumen weight was observed (P = 0.04). Dietary energy-to-protein ratio did not affect albumen weight in SGC breeders (; R2 = 0.89), but for EGC breeders, a higher dietary energy-to-protein ratio resulted in a 0.9 g lower albumen weight from 96% AMEn to 108% AMEn (, where was 43.4, 43.2, 42.8, and 42.5 for 96% AMEn, 100% AMEn, 104% AMEn, and 108% AMEn, respectively; R2 = 0.86). Albumen DM content decreased linearly with an increased dietary energy-to-protein ratio, but this was more profound in EGC breeders (β = −0.03 %/% AMEn) than in SGC breeders (β = −0.01 %/% AMEn; P = 0.03). Overall, it can be concluded that an EGC for breeders led to larger eggs with a more yolk and albumen, whereas dietary energy-to-protein ratio had minor effects on egg composition.

Effects of the In Ovo Vaccination of the ts-11 Strain of Mycoplasma gallisepticum in Layer Embryos and Posthatch Chicks.

Simple SummaryMycoplasma gallisepticum (MG) is responsible for reductions in egg production and other economic losses in the poultry industry. In this study, the potential application of in ovo vaccination of the ts-11of MG vaccine (ts-11MGV) in layer embryos for the subsequent early protection as well as live performance of pullets were investigated. The use of various dosages of live attenuated ts-11MGV ranging from 3.63 × 101 to 3.63 × 104 cfu that were delivered in ovo at 18 days of incubation were evaluated. The results of current study revealed that the in ovo injection of various dosage of ts-11MGV had no negative impacts on any hatch variables. Additionally, the higher dosage of ts-11MGV (3.63 × 104) resulted in a reduction in body weight gain in three-week-old pullets in comparison to all other treatments. Furthermore, MG DNA remained undetectable for hatchling and three-week-old pullets and no serological response was observed at 3 weeks posthatch. Total flock protection from field-strain MG infections is facilitated by the prior systemic establishment of vaccine strains in pullets. Therefore, it is concluded that the ts-11MGV may not be an appropriate candidate for in ovo injection due to the lack of its presence in hatchlings and posthatch chicks subsequent to its in ovo administration.The transmission of the ts-11 strain of Mycoplasma gallisepticum (MG) vaccine (ts-11MGV) between incubated eggs and between hatchlings that was administrated via in ovo injection, and its subsequent effects on their posthatch performance were evaluated. Marek’s disease diluent alone (sham-injected) or containing either 3.63 × 101, 102, 103, or 104 cfu of ts-11MGV was manually in ovo-injected into the amnion on 18 days of incubation. Egg residue analysis, percentage incubational egg weight loss, hatchability of viable injected eggs, and hatchling body weight (BW) were assessed. Selected hatchlings from each treatment replicate group were swabbed in the choanal cleft for MG DNA detection. Female chick live performance was also assessed through 21 days of posthatch age. Unexposed control sentinel chicks were allocated to each treatment replicate group to assess horizontal transmission. Birds were later swabbed and bled respectively, for detection of MG DNA and IgM production at 21 days posthatch. In all birds, no MG DNA was detected and SPA tests for IgM were negative. Among all variables, only 0 to 21 day BW gain was significantly affected by treatment and was lower in the 3.63 × 104 ts-11 MGV treatment in comparison to all the other treatments. Because ts-11MGV does not exhibit vertical or horizontal transmission capabilities under commercial conditions, it may not be a good candidate for in ovo injection.

The effect of the in ovo injection of some carbohydrates and antioxidants on incubating parameters, blood and immunological parameters, intestinal morphometry and post-hatching production performance in broiler chickens

This experiment was performed to evaluate the effect of the in ovo injection of carbohydrates, antioxidants, and their combination into the stored incubating eggs. To conduct this research, 600 hatching eggs were selected for amniotic injection (on 17.5th embryonic day) from the laying hens of Cobb 500 strain after 14 days of storage, and after hatching, they were distributed for a rearing period in 5 treatments and 5 replicates in a completely randomised design(24 eggs per replicate). Experimental treatments include: (1) Negative control (NC) (without injection), (2) Positive control (PC) (injection of 0.5 ml normal saline solution), (3) Injection of 0.5 ml carbohydrates solution (CS), (4) Injection of 0.5 ml antioxidant solution (AS) and (5) Injection of 0.5 ml (CS) + (AS). The hatching percentage, chicken weight, the number of red cells, lymphocytes and tissue glycogen content in CS + AS treatment increased significantly compared to the control (p<.05). All experimental treatments had a significant improvement compared to the control in terms of the physical quality of chickens and the performance in the entire rearing period (p<.05). Antioxidant activity of the liver tissue for the treatments injected with antioxidants had the most significant difference in comparison with the control (p<.05). The results show that the CS + AS injection leads to a higher improvement of incubation and growth performance by preventing the reduction of glycogen stores, as well as increasing the antioxidant capacity and protection of unsaturated lipids against the stress in hatching period in the stored fertile eggs. Highlights Increased egg storage time have detrimental effects on embryonic development and hatching rate. The in ovo injection of carbohydrates by improving glycogen stores in stored fertile eggs is effective in improving performance. The in ovo injection of antioxidants have positive effects on antioxidant activity of broilers.

Effect of In-ovo Injection of L-Arginine on Hatchability, Chick Quality, Performances and Muscle Histology of Native Chicken

This study aimed to determine the effect of in-ovo injection of L-arginine on hatchability, chick quality, performances, and muscle histology of native chicken. In-ovo injection was carried out on the 10th day. A total of 375 fertile eggs with an average weight ranged  39-43 g were grouped into 5 treatments. The first treatment was without injection (negative control), the second treatment was injection of NaCl solution 0.9% (positive control), the third treatment was injection of L-arginine solution 0.5 g per 100 ml of NaCl 0.9% (0.5%, m/v) The fourth treatment was injection of 1.0 g L-arginine solution per 100 ml of NaCl 0.9% (1.0%, m/v), and the fifth treatment was injection of 1.5 g L-arginine solution per 100 ml of NaCl 0.9% (1.5%, m/v). The injection was carried out at the pointed area of the egg in a vertical position (pointed below, blunt above). The Injection was carried out with a depth of 10 mm from the eggshell using an automatic injector. The results showed that all treatments produced the same hatchability. In-ovo injection of L-arginine has a beneficial effect on chick quality and post-hatch performance, the concentration of L-arginine solution used did not cause embryo death. In-ovo injection of 0.5% L-arginine increased hatching weight, weekly body weight, muscle mass, and myofiber size.

Kuluçka sırasında sıcağa alıştırma ve fotoperiyodik aydınlatmanın kuluçka performansı, kuluçka süresi, civciv kalitesi ve organ gelişimi üzerindeki etkisi

Objective: The objective of this study was to investigate the effects of thermal manipulation (TM) and photoperiodic lighting during the incubation on hatching performance, hatching time, chick quality and organ growth. Material and Methods: The study was composed of two consecutive experiments. The 1st experiment was application of TM, 1ºC higher eggshell temperature (EST, 38.8ºC ) for 6 h/day from 11 to 16 embryonic day, or optimal EST of 37.8ºC (Control) during the incubation. In second experiment, eggs were exposed to a photoperiodic lighting of 16h light and 8h darkness (16L: 8D) along with optimal EST (Light-Control) or TM (Light-Heated). Results: Thermal manipulation accelerated hatching time, reduced chick quality score, decreased relative bursa and tibia weights while heart and sternum weights increased with no effect on hatching performance. However, 16L: 8D photoperiodic lighting schedule along with TM significantly improved chick length at hatch indicating improved chick quality while other traits were not affected except for higher relative liver weight. Conclusion: It can be concluded that TM alone had negative effects on chick quality. However, photoperiodic lighting along with TM can be a positive approach towards better chick quality and post hatch performance as indicated by increased chick length and liver weight.

Effects of pre-incubation storage duration and nonventilation incubation procedure on embryonic physiology and post-hatch chick performance

This study investigated the effects and possible interactions of storage and nonventilation during incubation for eggs from Sasso broiler breeder flock on pre- and post-hatch incubation results.A total of 1,260 Sasso eggs from a 58-wk-old broiler breeder flock were individually numbered, weighed and stored for 7 d or for 18 d in a climate-controlled room (16°C, 75% RH). After storage, eggs were weighed, and randomly assigned equally into 2 incubators. One of the incubators was ventilated (V) for the entire incubation and the second was nonventilated (NV) for the first 12 d. At d 18, the eggs were weighed, candled, and fertile eggs were transferred from the turning trays to hatching baskets. During the last 3 d of incubation, hatching eggs were checked individually every 3 h for hatching events and hatchability of fertile eggs. After pull out at d 21.5, post-hatch performances was determined until 1 wk of age.Results showed that, embryo weights from eggs in NV incubator was significantly higher (P < 0.05) in both stored eggs compared to those from eggs in ventilated incubator, but embryos from eggs stored for 18 d were smaller (P < 0.05) than those from eggs stored for 7 d. Hatchability was higher (P < 0.0001) in NV incubator compared to V incubator in both 7 d and 18 d stored eggs and an interaction was found between incubation ventilation and storage duration on both hatchability and embryonic mortality (P < 0.0001). Chick weights from NV incubator at 7 d post-hatch was greater (P = 0.0009) than those from V incubator. Serum Tri-iodothyronine (T3) and Thyroxin (T4) concentrations were significantly higher (P < 0.05) in NV compare to V group.It was concluded that the effect of long-term pre-incubation storage on embryonic physiology and post-hatch growth interacted significantly with incubation ventilation and that nonventilation can compensate for the negative effects of storage on some hatching and post-hatch performances.

Effect of lower temperature stimuli during incubation on fear and social-related behaviours in broilers

Temperature is the most influential environmental parameter during egg incubation affecting embryo development, hatchability and post-hatch performance of broilers. Industrial incubation operates to control the temperature and humidity around the eggs closely based on predefined setpoints and keep fluctuations to a minimum. On the other hand, during brooding, the mother hen regularly leaves the nest for self-maintenance resulting in a striking difference between the constant industrial versus fluctuating natural incubation temperature profiles. Previous studies on ducks and laying hens have found fear and/or social behaviours to be affected by temperatures below recommended values during incubation, a similar result could be existing in commercial broilers. Therefore, this study examines the effect of lowering machine temperatures during incubation on behaviour. Three incubation treatments were defined with a constant machine temperature of 37.6 °C on embryonic day (ED) 0–13 and 19–21 with the machine temperature differing on ED 13–18: (1) Control (C; 37.6 °C), (2) non-optimal Incubation Treatment (IT; 36.6 °C), (3) Natural Treatment (NT, 30 °C for 30 min per day). Post-hatch fear and social behaviour were quantified using six scientifically accepted behavioural tests: three fear tests (novel object on day (d) 1 and d8, tonic immobility (d40), inversion (d42)), two social tests (isolation (d19) and social reinstatement (25)) and one social/fear test (emergence (d18 and d20)). For the emergence test, wherein the time taken for an individual chick to emerge from a T-shaped box was measured, a treatment effect was found on the latency to emerge (P < 0.05) with C chicks emerging more often and faster than IT chicks. As no differences for IT were found in other social tests, the emergence suggest IT chicks to be more hesitant towards novel environments. No differences were present between NT and C or NT and IT. For the isolation test, where an individual chick is visually and audibly isolated for 3 min and the number of vocalisations was measured, an interaction was found between treatment and sex (P < 0.001). Females vocalised more than males in IT and C, but this was not the case for NT. NT male chicks could thus be considered more sensitive to social separation, which could be explained by the higher impact of early stress, caused by the severe temperature drops in NT, having a stronger impact on the anxiety behaviour of males compared to females in later life.

Effects of hypoxic conditions during the plateau period on pre- and posthatch broiler performance

Adequate ambient temperature and oxygenation are necessary to maintain normal embryonic development of broilers; however, hypoxia challenge during incubation can aid in improving regulatory plasticity and lead to different phenotypes later in life. This study aimed to examine the effects of moderate hypoxia (O2 17%) during the plateau phase on the embryonic physiological parameters and on posthatch performance (growth rate, feed consumption and feed conversion) up to the age of poultry marketing. The study included examined embryos exposed to O2 17% for 12 h per day (h/d) from E16 through E18 (designated as 12H), or O2 17% continuously, from E16 through E17 (designated as 48H) and a standard incubation control group (21% O2). Physiological and morphological parameters of embryos and hatched chicks were measured. Male Chicks from all 3 treatment groups were raised under recommended temperature regime, and body weight, feed intake and FCR were recorded on a weekly basis. The intermittent hypoxia protocol (12H), allowed embryos to properly adapt to the shortage of oxygen, compensate for the gap in body mass that developed following the first exposure window, and hatch with characteristics similar to those of the control embryos. In contrast, while the 48H embryos were able to adapt to the hypoxic stress, the prolonged exposure prevented them from catching up with both control and 12H embryos. Broilers that were subjected to hypoxia showed hatchling body weights and growth rates similar to those of controls, throughout the entire growth phase. During the fifth wk, lower feed consumption was observed in the 12H and 48H groups and became significantly lower than the control chicks in the sixth wk of growth. Following hypoxia exposure, chicks managed to reach normal body weight with less feed, with the 12H group demonstrating lower and more efficient FCR during the last 2 wk of growth.Broiler embryos reacted to plateau-phase hypoxia challenge with numerous physiological and metabolic modifications. The prudent alterations in metabolism and cardiovascular system during exposure to hypoxia and posthatch, resulted in more efficient energy utilization in broilers, which may have a long-lasting enhancing effect on posthatching thermotolerance and sustainability in chicks reared under sub-optimal environmental conditions.

Effects of low eggshell temperatures during incubation, in ovo feeding of L-arginine, and post-hatch dietary guanidinoacetic acid on hatching traits, performance, and physiological responses of broilers reared at low ambient temperature

This study aimed to investigate the effect of eggshell temperature (ET) manipulations during incubation, in ovo feeding (IOF) of arginine, and post-hatch dietary supplementation with guanidinoacetic acid (GAA) on hatching traits and subsequent growth and physiological performance of hatched broiler chicks reared under subnormal temperature. In experiment 1, from d 8 of incubation onward, a total of 2,160 hatching eggs were randomly arranged in a 2 × 3 factorial design, in which the eggs were exposed to 2 ET (37.8°C or periodically low ET), and 3 IOF treatments (noninjected, diluent-injected, and 1% arginine solution-injected). In experiment 2, a total of 576 one-day-old male broiler chicks from 2 temperature conditions and 2 IOF treatment groups (noninjected and Arg-injected) were reared for 42 d with or without GAA supplementation in a 2 × 2 × 2 factorial design. Each treatment had 6 replicates with 12 birds each. A subnormal ambient temperature (17°C) was applied from 15 d onward to induce ascites. Results from experiment 1 showed a 2-way interaction between ET and IOF for embryonic mortality rate during 19 to 21 d of incubation and residual yolk weight at hatch (P < 0.05). A periodically low ET significantly increased yolk free body mass, first-grade chicks, and relative heart weight than an ET of 37.8°C. In the second experiment, overall average daily gain (ADG) was increased, but feed conversion ratio (FCR), ascites mortality, and serum thyroid hormones and corticosterone were reduced in the low ET group (P < 0.05). There were also IOF × GAA interactions for ADG and FCR (P < 0.05). IOF of arginine or dietary GAA increased serum nitric oxide concentration and jejunal villus height, but decreased ascites mortality (P < 0.05). In conclusion, a periodically low ET accompanied by IOF of arginine during incubation and posthatch dietary supplementation with GAA could be a useful strategy for improving the chick quality at hatch and subsequent improvements in post-hatch performance and ascites indices in cold-stressed broilers.

129 Maternal Nutrition and in Ovo Feeding Affect Gut Health and Performance of Poultry

Abstract Maintaining a healthy gastrointestinal tract (GIT) is critical for better nutrient utilization, optimum performance, and overall health of poultry. Thus, several nutritional strategies have been tried to improve poultry’s gut health. More recently, different nutrients and feed additives are being used in poultry diets with some success when antibiotic growth promoters (AGP) are not an acceptable option anymore. However, effective modulation of gut health depends on the methods and timing of the compound being available to host animals. Routinely, the alternatives to AGP like prebiotics, probiotics, symbiotic, enzymes, and other nutrients are provided in feed or water to poultry. However, the GIT of the newly hatched poultry is functionally immature, despite going through significant morphological, cellular, and molecular changes toward the end of incubation. Thus, the early growth and development of GIT are of critical importance to enhance nutrients utilization and optimize the growth performance of poultry. Maternal nutrition and in ovo feeding have been used and found to be effective in improving gut health but with inconsistent results. The effects of maternal nutrition on the development and viability of embryo and post-hatch growth performance of birds are documented. However, there is limited information on how maternal nutrition affects the gut health of chicks. In contrast, information on the same from in ovo feeding of nutrients and feed additives has increased in recent years. The results show that in ovo feeding can be a good tool to modulate gut health of post-hatch birds positively. However, more information is needed on the proper route and time of inoculation, optimum doses, and effective combination of different compounds to maximize the benefits of in ovo feeding technique in poultry production.

Pre-fertilization exposure of sperm to nano-sized plastic particles decreases offspring size and swimming performance in the European whitefish (Coregonus lavaretus)

Exposure of aquatic organisms to micro- and nano-sized plastic debris in their environment has become an alarming concern. Besides having a number of potentially harmful impacts for individual organisms, plastic particles can also influence the phenotype and performance of their offspring. We tested whether the sperm pre-fertilization exposure to nanoplastic particles could affect offspring survival, size, and swimming performance in the European whitefish Coregonus lavaretus. We exposed sperm of ten whitefish males to three concentrations (0, 100 and 10 000 pcs spermatozoa−1) of 50 nm carboxyl-coated polystyrene spheres, recorded sperm motility parameters using computer assisted sperm analysis (CASA) and then fertilized the eggs of five females in all possible male-female combinations. Finally, we studied embryonic mortality, hatching time, size, and post-hatching swimming performance of the offspring. We found that highest concentration of plastic particles decreased sperm motility and offspring hatching time. Furthermore, sperm exposure to highest concentration of plastics reduced offspring body mass and impaired their swimming ability. This suggests that sperm pre-fertilization exposure to plastic pollution may decrease male fertilization potential and have important transgenerational impacts for offspring phenotype and performance. Our findings indicate that nanoplastics pollution may have significant ecological and evolutionary consequences in aquatic ecosystems.

RESPONSE OF BROILER CHICKEN TO INOVO ADMINISTRATION OF DIFFERENT LEVELS OF ROSEMARY OIL(ROSMARINUS OFFICINALIS)

This study was conducted to determine the percentage of hatchability, post-hatch growth performance, immune response of broiler subjected to in- ovo injection of different doses of rosemary oil. A total of 300 eggs of ross broiler strain were obtained.The experiment distributed into five treatment groups: T1, Negative Control T2, positive control (in ovo injection of 0.05 ml distilled water) T3, in ovo injection of 0.05ml of rosemary oil; T4, in ovo injection of 0.075 ml of rosemary oil; T5, in ovo injection of 0.1 ml of rosemary oil.Highest hatchability percentage was shown in 0.1ml rosemary oil -injected hatching eggs. The final weight of birds from 0.075 and 0.1 ml of rosemary oil-injected eggs was significantly (P &lt; 0.05) highest through the experiment. Feed intake and feed conversion ratio were improved with in ovo administration of rosemary oil at 0.075 and 0.1 ml doses. In addition, the level of blood cholesterol and blood glucose were decreased (p&lt;0.05) in birds from rosemary oil-injected eggs. The obtained data showed a positive effect of in-ovo injection of rosemary oil on stimulating bird's immunity.

Effects of egg storage duration on egg quality, metabolic rate, hematological parameters during embryonic and post-hatch development of guinea fowl broilers

Considering the value of guinea fowl keets, successful incubation of eggs is particularly desirable in this poultry species. This study evaluated the effect of egg storage duration on egg quality, heat production, hematological parameters during embryonic development and post hatch performance of guinea fowl broilers. A total of 800 hatching eggs of guinea fowl were used for this study. Before incubation, 12 eggs per treatment were used to analyse egg quality. Then, eggs were numbered, weighed, and assigned to 2 treatment groups of 400 eggs each according to storage duration of 5, and 10 d at a temperature of 18°C. The eggs were set for incubation at 37.7°C and 55% relative humidity for 28 d in a forced-draft incubator. To determine heat production as a measure of metabolism, 60 eggs in each replicate were transferred to respiratory cages post hatch two 12 wk old guinea fowl were also used to determine heat production. CO2 and O2 were recorded to calculate heat production at internal pipping, hatch and at 12 wk of age. The hatched keets were reared for 12 wk and data were collected on feed intake, body weight and feed conversion ratio. Blood samples were collected at hatch and at 12 wk of age from 24 guinea fowls per treatment to analyze haematological parameters. The results showed that embryos and guinea fowls at 12 wks of age from eggs stored for 5 d had higher (P ˂ 0.05) heat production and body weights. However, a significant higher (P ˂ 0.05) level of basophile, eosinophils, and lymphocytes was observed in guinea fowls from 10 d storage egg. It was concluded that extended duration of egg storage negatively influenced the metabolic rate of embryos. It also impacted hematological parameters which may suggest influence on immune response during embryonic and post-hatch growth.

Effects of in ovo injection of Manihot esculenta extract on hatchability and post-hatch performance of Sasso broiler chickens

Abstract Manihot esculenta leaf meal in feed at post-hatch improves growth and egg production. One may question the efficacy of Manihot esculenta leaf extract for in ovo feeding. This study was conducted to determine the effects of in ovo injection of Manihot esculenta extract on hatchability, growth performance and biochemical parameters of Sasso broiler chickens. The hatching eggs from 38-week-old broiler breeders were set and at d 18 of incubation, 600 eggs with evidence of living embryos were assigned to 4 treatment groups of 150 eggs each. These groups were: (1) eggs without in ovo injection (negative control); (2) eggs perforated but no injection of any additive (positive control); (3) eggs perforated and injected with 0.1Â ml of saline solution and (4) eggs perforated and injected with 0.1Â ml of Manihot esculenta extract. Data were collected on hatching performance. During the post hatch growth phase, performance traits such as feed intake, weight gain, and feed conversion ratio were collected and at 84 days of age, blood samples were taken for determination of serum total proteins, triglycerides, aspartate aminotransferase (ASAT) and alanine amino transaminase (ALAT). The results showed that hatchability was similar in the negative control and Manihot esculenta extract groups but significantly higher (PÂ <Â 0.05) than those of positive control and saline solution treatment groups. Chick quality was better in the groups with Manihot esculenta extract and saline solution application. Post-hatch, the body weight gain of birds from the Manihot esculenta extract group was higher than those in the groups with saline solution application and in the negative control and positive control groups. Manihot esculenta leaf extract increased significantly the triglyceride rate and reduced ALAT and ASAT concentration at hatch. It can be concluded that in ovo inoculation of 0.5Â μg/ml Manihot esculenta leaf extract on d 18 of incubation into the eggs air chamber improved hatchability, chick quality and post-hatch growth of broilers.