Post-hatch Performance Of Broilers Research Articles

Supply and demand of creatine and glycogen in broiler chicken embryos.

Optimal embryonic development and growth of meat-type chickens (broilers) rely on incubation conditions (oxygen, heat, and humidity), on nutrients and on energy resources within the egg. Throughout incubation and according to the embryo's energy balance, the main energy storage molecules (creatine and glycogen) are continuously utilized and synthesized, mainly in the embryonic liver, breast muscle, and the extraembryonic yolk sac (YS) tissue. During the last phase of incubation, as the embryo nears hatching, dynamic changes in energy metabolism occur. These changes may affect embryonic survival, hatchlings' uniformity, quality and post hatch performance of broilers, hence, being of great importance to poultry production. Here, we followed the dynamics of creatine and glycogen from embryonic day (E) 11 until hatch and up to chick placement at the farm. We showed that creatine is stored mainly in the breast muscle while glycogen is stored mainly in the YS tissue. Analysis of creatine synthesis genes revealed their expression in the liver, kidney, YS tissue and in the breast muscle, suggesting a full synthesis capacity in these tissues. Expression analysis of genes involved in gluconeogenesis, glycogenesis, and glycogenolysis, revealed that glycogen metabolism is most active in the liver. Nevertheless, due to the relatively large size of the breast muscle and YS tissue, their contribution to glycogen metabolism in embryos is valuable. Towards hatch, post E19, creatine levels in all tissues increased while glycogen levels dramatically decreased and reached low levels at hatch and at chick placement. This proves the utmost importance of creatine in energy supply to late-term embryos and hatchlings.

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.

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 supplementing silver nanoparticles during early embryogenesis on the hatchability and post hatch performance of broilers

The aim of the present study was to investigate the role of silver nanoparticles (AgNano) supplementation during early embryogenesis on the post-hatch performance and immunity in broilers. Increasing concentration of AgNano 0 (un-injected control), 12.5, 25 and 50 μg/egg, respectively were administered on 7th embryonic day at the broad end of broiler egg, following in ovo feeding techniques. A total of 60 eggs per treatment were used and five replicates of 8 birds each in all treatment were reared upto 42 days post-hatching. Egg weight, chick weight and ratio were similar in all the groups, however, the hatchability decreased with increasing AgNano concentration. Average daily weight gain was increased in all the AgNano supplemented chicks. Average daily feed intake and feed conversion ratio were not affected by AgNano supplementation. Pancreas weight has shown an increasing trend with increasing concentration of AgNano. The bursa and spleen weight were increased with increasing concentration of AgNano supplementation during embryogenesis. In vivo Immune-response to phytohaemagglutinin- P and sheep RBC was increased in AgNano supplemented chicks. Serum cholesterol level was decreased in AgNano supplemented chicks unlike glucose and total protein. Early embryonic supplementation of AgNano particles modulates the post-hatch growth performance and immunity in broilers.

In ovo injection with glycerol and insulin-like growth factor (IGF-I): hatchability, intestinal morphometry, performance, and carcass characteristics of broilers

ABSTRACT The objective of this study was to evaluate the effects of in ovo injection with glycerol (GLY) and insulin-like growth factor (IGF-I) on hatchability, biochemical parameters, intestinal morphometry, performance, and carcass characteristics of broiler chickens. A total of 400 fertilised eggs were distributed into five experimental groups. The treatments were arranged as non-injected (control), saline solution injected (0.9% NaCl solution), GLY solution injected (10 nmol/ml), IGF-I solution injected (100 ng/ml), and GLY + IGF-I solution injected. At 17.5 d of incubation, 0.5 ml of each solution was injected into the amniotic fluid of each egg of the injected groups. The injection of different solutions did not influence the hatchability and incubation time of the eggs. Compared to intact eggs, IGF-I and IGF-I+ GLY increased (p < 0.01) the blood IGF-I at hatching. Higher hepatic glycogen was observed (p < 0.05) with GLY or IGF-I. The tested substances decreased (p = 0.02) the fructose 1,6-biphosfate phosphatase activity but did not affect glycaemia. No difference in performance was observed in the first week. Higher feed intake and weight gain with lower feed conversion ratio was obtained ( p < 0.05) with IGF-I at 14 d. At 21 d, higher weight gain was obtained (p = 0.05) with IGF-I, GLY, IGF-I, and GLY + IGF-I, resulting (p < 0.01) in birds with greater weight gain at 35 and 42 d of age. GLY provided higher villus height in the ileum at hatching and at 7 d of age. The tested solutions increased the relative weight of the liver at hatching. At 42 d of age, no carcass characteristics were influenced. It is concluded that GLY and IGF-I, together or separately, can be used in the in ovo feeding to improve the post-hatch performance of broilers, without affecting hatchability and carcass composition.

Effects of low oxygen during chorioallantoic membrane development on post-hatch growing performance of broiler chickens.

The prenatal circulatory system is adaptive and capable of plasticity designed for the needs of the growing tissue. When a broiler embryo is faced with hypoxic stress, the process of angiogenesis in tissues begins. Exposure to hypoxic conditions of 17% oxygen during the chorioallantoic membrane (CAM) development (E5 to E12) affected the circulatory system and contributed to an increase in the blood oxygen carrying capacity. The present study aimed to evaluate the effects of hypoxic exposure during CAM development on post-hatch performance of broilers and to examine whether hypoxic exposure improved sustainability of birds exposed to acute heat stress.Two consecutive trials, with male broilers from each of the incubation treatments-optimal conditions and exposure to hypoxia of 15 or 17% oxygen, for 12h/day, during CAM development-were conducted. In experiment 1, 60 male chicks from each group were raised in individual cages. In experiment 2, 160 male chicks from each group were raised in 40-chick pens until marketing. On d 35, 20 birds from each group were transferred to individual cages kept at a temperature of 23°C for 72h, and then birds were exposed to 35°C for 5hours. Body temperatures were measured at 0, 2, and 5h of the heat exposure. In both experiments BW, feed intake, and FCR were recorded. At marketing, chicks were slaughtered, and relative weights of breast muscle, abdominal fat pad, heart, and liver were calculated.Hypoxia treatment resulted in a FCR advantage. Food intake was similar in all treatments, but groups exposed to hypoxia grew better than controls until the age of 35 days. Hypoxia-treated groups had higher relative breast, heart, and liver weights than controls. Body temperatures of hypoxia-treated chickens remained lower during heat stress exposure, and their mortality rate was lower as well. Intermittent exposure to moderate hypoxia during CAM development confers advantages to broilers in feed utilization efficiency and in coping with heat stress. It may be considered as a mitigating step in incubation to facilitate broilers in achieving their full growth potential.

Impacts of Breeder Age, Storage Time and Setter Ventilation Program on Incubation and Post-Hatch Performance of Broilers

ABSTRACT The impacts of breeder age (32 and 55 weeks), egg storage time (2-12 days), setter ventilation program (control-test) on incubation and post-hatch performance of broilers were investigated in this study. Young (Y) and old (O) breeders’ hatching eggs were incubated in two different setters operated by two different ventilation programs as control (C) and test (T). Incubation took place after a short (S) and long (L) time of storage in this study. According to the trial design, eight treatment groups were as YSC, YST, YLC, YLT, OSC, OST, OLC and OLT. In total 9600 eggs and 6400 chicks were used. Early stage embryonic mortality (ED) rates were lower and accordingly hatchability of fertile eggs (HF) were higher (p<0.05) in YS than the other treatment groups. In contrast, incubation performance in eggs hatched in C and T programs were found to be similar. However, interaction between treatments were significant (p<0.05) and ED and HF were significantly (p<0.05) improved at OC. Liveability in growing period was affected (p<0.05) by breeder age but it wasn’t affected by storage time and incubation program. Higher post-hatch performance was achieved in chicks of OST but differences between groups weren’t significant except for chick weights in comparison by breeder age. However, interactions between treatments were significant (p<0.05) and reached the highest post-hatch performance in YST (p<0.05). In conclusion, the long time storage of old breeders’ eggs improved incubation and post-hatch performance when they were incubated at test program.

Effects of coccidiosis vaccination administered by in ovo injection on Ross 708 broiler performance through 14 days of post-hatch age

Effects of the in ovo injection of a commercial coccidiosis vaccine on various hatching chick quality variables and 14 d post-hatch (dph) oocyst shedding have been previously examined. The current study was designed to examine the performance of Ross 708 broilers during the 14 dph period of oocyst shedding following the application of the coccidiosis vaccine. On each of 7 replicate tray levels of a single-stage incubator, a total of 4 treatment groups was randomly represented, with each treatment group containing 63 eggs. Treatments were administered using a commercial multi-egg injector on d 18.5 of incubation. The treatments included 3 control groups (non-injected, dry-punch, and diluent-injected) and one treatment group (injected with diluent containing Inovocox EM1 vaccine). On d 21 of incubation, 20 chicks from each of the 28 treatment-replicate groups were placed in corresponding wire-floored battery cages. Mortality, feed intake (FI), BW gain (BWG), and feed conversion ratio (FCR) were determined for the zero to 7, 7 to 14, and cumulative zero to 14 dph intervals. There were no significant treatment effects on mortality in any interval or on BW at zero dph. There were significant treatment effects on BW at 7 and 14 dph, on BWG and FI in the zero to 7, 7 to 14, and zero to 14 dph intervals, and on FCR in the 7 to 14 and zero to 14 dph intervals. Although the performance variables of birds belonging to the diluent-injected and vaccine-injected groups were not significantly different, the 14 dph BW, 7 to 14 dph FI, and zero to 14 dph BWG and FI of birds belonging to the vaccine treatment group were significantly higher than those in birds belonging to the non-injected control group. It was concluded that use of the Inovocox EM1 vaccine in commercial diluent has no detrimental effect on the overall post-hatch performance of broilers through 14 dph.

In ovo silver nanoparticle supplementation for improving the post-hatch immunity status of broiler chickens

ABSTRACTSilver nanoparticles (AgNano) are known for their unique physical, chemical and biological properties, enabling cell penetration and anti-inflammatory response. In Experiment 1, the effect of an in ovo administration of AgNano (15 µg/egg; n = 360) at different incubation times (d 7 and d 18) on hatchability parameters was explored. In Experiment 2, post-hatch performance of broilers (42 d, n = 250) was studied after in ovo AgNano administration: Group T1 remained un-injected, Group T2 was the sham control and Groups T3, T4 and T5 were injected with 12.5, 25 and 50 µg AgNano, respectively, at 18 d of incubation. Chick weight, chick to egg weight ratio and hatchability as well average daily gain, average daily feed intake and feed conversion ratio were similar in all treatment groups. No variation was seen in the weight of thymus; however, the bursa and spleen weight was increased (p < 0.05) in Groups T4 and T5 in comparison to Group T1. The in vivo immune response to phytohaemagglutinin-P was increased in Group T3 in comparison to Groups T1 and T2 (p < 0.05), while the response to sheep red blood cells was increased in all AgNano-treated groups in comparison with Group T1 (p < 0.01). The expression of toll-like receptors 2 and 4 genes was up-regulated in AgNano groups in comparison with Groups T1 and T2 (p < 0.01). In summary, an in ovo supplementation of AgNano carried out at d 18 of incubation is effective and modulates the post-hatch immune response without affecting the hatchability, growth and other performance parameters in broilers.

Effects of the commercial in ovo injection of 25-hydroxycholecalciferol on broiler posthatch performance and carcass characteristics ,

In ovo injection of 25-hydroxycholecalciferol [25(OH)D3] has been shown to improve hatchability of injected broiler eggs. Effects of the in ovo injection of commercial diluent containing various levels of 25(OH)D3 on broiler posthatch performance and carcass characteristics were investigated in 2 trials. On each of 10 tray levels of a single-stage incubator, all treatment groups were randomly represented with each containing 21 and 40 eggs in trials 1 and 2, respectively. Treatments included noninjected and diluent-injected (100 µL commercial diluent-injected) controls, and those that received 0.15, 0.30, 0.60, or 1.20 µg of 25(OH)D3 in trial 1 and 0.20, 0.60, 1.80, or 5.4 µg of 25(OH)D3 in trial 2, in 100 µL of commercial diluent using a commercial multi-egg injector on d 18 of incubation. On d 21 of incubation, chicks from each treatment replicate group were placed in corresponding floor pens. Feed intake, BW gain, and feed conversion were determined for the weekly and cumulative 0 to 21 d age intervals in trial 1 and for the weekly and cumulative 0 to 48 d age intervals in trial 2. In trial 2, 2 birds from each sex were selected from each treatment replicate group for determination of processing carcass characteristics on d 49 posthatch. Feed intake in the 0 to 7, 7 to 14, and 14 to 21 d age intervals and BW gain in the 0 to 7 and 14 to 21 d age intervals were affected by treatment in trial 2. The in ovo injection of up to 1.20 and 0.60 µg of 25(OH)D3 in trials 1 and 2, respectively, did not affect the BW gain of birds during the 0 to 7, 7 to 14, and 14 to 21 d age intervals compared with the noninjected and diluent-injected control groups. It was concluded that the in ovo injection of up to 1.20 µg of 25(OH)D3 into the amnion has no detrimental effect on the overall posthatch performance of broilers.

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.