Breeder Hens Research Articles

A Smart Intelligence System for Hen Breed and Disease classification using Extra Tree classifier-based Ensemble Technique

This research paper probes into the vital importance of poultry farming, specifically focusing on hens, which play a vibrant role in meeting the global demand for both eggs and meat. Identifying hen breeds and recognizing diseases pose significant challenges in poultry management, necessitating innovative solutions to enhance the efficiency of farming practices. The experimental efforts of this study were centered around classifying ten distinct hen breeds and recognizing four prevalent hen diseases through the implementation of an ensemble method. Utilizing a stacking-based ensemble approach, we achieved remarkable success, achieving a test accuracy of 99.94% for both hen breeds and 99.01% for disease classification based on feces images. In this study, we employed the self-collected dataset named ‘GalliformeSpectra’ for hen breed recognition, alongside a publicly accessible dataset of feces images to identify diseases. Additionally, to facilitate practical application, we have developed a smartphone application seamlessly incorporating our model, enabling real-time hen breed and disease classification. The findings of this study represent a groundbreaking accomplishment in the realm of hen breed classification using machine learning, distinguishing this study as both state-of-the-art and pioneering. By addressing critical challenges in poultry farming, this research contributes not only to academic progress but also provides practical solutions to enhance efficiency and sustainability in the poultry industry resulting in ease the farmers to be able to plan their farming business efficiently and to take measures in the correct time in case of diseases outbreak thus contributing to farmers, communities, and researchers.

Can chick meconium serve as a source of biomarkers linked to hatchling quality and the age of parent stock?

One possible approach to selecting chicks based on quality involves identifying biomarkers in biological samples. Concurrently, understanding the metabolic profile of chicks from different-aged breeders is essential for developing strategies to mitigate the age-related effects on hatchability. This study investigated whether chick quality and breeder age influence the metabolic profile of layer chick meconium. A total of 143 chicks from laying breeder hens, categorized as young, middle-aged or old, were visually assessed for quality, and meconium samples were collected for metabolomic analysis. Sixteen metabolites were found to be associated with good-quality chicks across all breeder ages, with an overall accuracy of 81.94 %. Using metabolite profiles, the accuracy for predicting young-hen-chick quality was 93.2 %, with high sensitivity (92.30 %) and specificity (93.75 %). Four metabolites were associated with poor-quality chicks with an overall accuracy of 77.53 %. Partial least squares discriminant analysis (PLS-DA) revealed enhanced metabolite separation in good-quality chicks, with five metabolites exhibiting high area under the curve (AUC) values (>90 %) in chicks from young hens compared to chicks from hens of other ages, including metabolites related to energy metabolism, hormonal activity, vitamin D synthesis and peptide constitution. Disregarding maternal age, five metabolites varied between good- and poor-quality chicks, but with a low accuracy of 61.26 % for quality discrimination. Chicks from young, middle-aged, and old hens exhibited 12, 11, and 2 metabolites that varied the expression between good and poor qualities, with accuracies for predicting good-quality chicks of 74.46 %, 70.83 %, and 51.06 %, respectively. Certain metabolites with 70 < AUC < 80 % have emerged as potential biomarkers for distinguishing between good- and poor-quality layer chicks. These include metabolites related to energy and growth metabolism, tryptophan and methionine metabolism, antioxidants and some with no known function in embryos. This work identified potential metabolites that can be investigated to mitigate the effects of hen age on hatchability. Additionally, several metabolites have emerged as potential biomarkers for distinguishing between good- and poor-quality chicks, depending on the breeder's age.

Research Note: Do broiler breeder hens use hypothermia to cope with cold environments and feed restriction?

Research Note: Do broiler breeder hens use hypothermia to cope with cold environments and feed restriction?

Goose Deoxycholic Acid Ameliorates Liver Injury in Laying Hens with Fatty Liver Hemorrhage Syndrome by Inhibiting the Inflammatory Response

Fatty liver hemorrhagic syndrome (FLHS) in laying hens is a nutritional and metabolic disease involving liver enlargement, hepatic steatosis, and hepatic hemorrhage as the primary symptoms. The syndrome is prone to occur during the peak laying period of laying hens, which has resulted in significant economic losses in the laying hen breeding industry; however, the specific pathogenesis of FLHS remains unclear. Our group and previous studies have shown that bile acid levels are significantly decreased during the development of fatty liver and that targeted activation of bile acid–related signaling pathways is beneficial for preventing and treating fatty liver. In this study, we generated a FLHS laying hen model by feeding hens a high-energy, low-protein diet, with goose deoxycholic acid (CDCA) given as an intervention. HE staining, fluorescence quantitative PCR, and ELISA were used to evaluate the effects of CDCA on pathological changes and inflammatory responses in the liver. The results showed that hepatic hemorrhage in FLHS laying hens was reduced after CDCA treatment. Furthermore, fat vacuoles and transaminase levels decreased significantly. In addition, expression levels of M1-type macrophage markers and polarization products were significantly reduced, and the expression of pro-inflammatory regulatory factors related to the JAK-STAT signaling pathway, LPS-TLR4-Myd88–NF-kB signaling pathway, and NLRP3 inflammasomes decreased significantly as well. Expression levels of M2-type macrophage markers and polarization products increased significantly, as did the expression of anti-inflammatory regulators related to the JAK-STAT signaling pathway. These results suggest that CDCA ameliorates liver injury in laying hens with FLHS by inhibiting macrophage M1-type polarization and the resulting pro-inflammatory response, thereby promoting M2-type macrophage polarization and an anti-inflammatory response.

Modification of the terms of authorisation of the feed additive consisting of a preparation of canthaxanthin (CAROPHYLL® Red 10%) for breeder hens to include canthaxanthin produced with Yarrowia lipolytica CBS 146148 (DSM Nutritional Products Ltd.).

Following a request from the European Commission, the EFSA was asked to deliver a scientific opinion on the proposed modification of the terms of the authorisation of the feed additive consisting of a preparation of canthaxanthin (CAROPHYLL® Red 10%), regarding the addition of a new production route, by the yeast Yarrowia lipolytica CBS 146148 and to modify the additive specifications by substituting ethoxyquin by 4.4% butylated hydroxytoluene (BHT) and increasing the limit for dichloromethane to 80 mg/kg. The additive is already authorised as zootechnical feed additive for breeder hens. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded. CAROPHYLL® Red 10% containing canthaxanthin produced by fermentation with Yarrowia lipolytica CBS 146148 is safe for the target species, consumer and environment under the current authorised conditions of use for CAROPHYLL® Red 10%. Regarding user safety, canthaxanthin is not irritant to skin and eyes and unlikely to be a skin sensitiser. No conclusion can be reached on the respiratory sensitisation of canthaxanthin. In the absence of data with the additive CAROPHYLL® Red 10%, no conclusions can be reached regarding the safety of the additive for the user. CAROPHYLL® Red 10%, containing canthaxanthin produced by fermentation with Yarrowia lipolytica CBS 146148, is efficacious in breeder hens at 6 mg/kg complete feed.

Are domestic chickens born with predator recognition? Validation of a sound playback experiment.

Predation risk can influence behavioral decisions of animals in various ways. Prey animals have the opportunity to choose antipredation behaviors and escape strategies only by quickly and accurately identifying predators. As precocial birds, domestic chickens (Gallus gallus domesticus) have no adaptation period after hatching and must immediately survive under predation risk. They possess a strong ability to identify threats through vocalizations. To explore whether domestic chickens have innate predator recognition ability and whether the antipredation behavior of breeding chickens is stronger than that of non-breeding chickens. We tested the antipredation behaviors of three types of flocks (non-breeding chickens; hen with chicks; isolated chicks) of domestic chickens in response to sparrowhawk (Accipiter nisus) calls using playback experiments, while Oriental turtle dove (Streptopelia orientalis) calls were used as a control. We found that breeding hens are significantly more vigilant than non-breeding chickens. We also found that although isolated chicks can exhibit antipredator behavior, they cannot accurately identify the calls of predators and non-predators. Therefore, it can be concluded that domestic chickens exhibit varying degrees of vigilance towards predator calls at different stages of their life history. Reproductive costs can lead to increased vigilance in domestic chickens. The accurate identification of predators by domestic chickens is not innate, but gradually formed over time.

Effects of Formula Product Injection on Hatching Parameters, Small Intestinal Development and Ileum Histology in Breeder Chicken Eggs.

This study aimed to determine the effects of in ovo formula product injection on hatching parameters, chick quality, small intestinal development and ileum histology of breeder hen eggs. A total of 400 fertilised eggs were obtained from the Atak-S parent flock at 42 weeks of age for the experiment. The experiment was designed in two groups: a control group (C), in which no injection was performed, and the other group in which a solution containing formula products at concentrations of 1.25% (F1), 2.5% (F2) and 5% (F3) was injected into 0.5mL/egg air sac. The hatching rate, embryonic mortality and discard chick rate were examined at the end of the trial. The best result of the hatching rate was found in the Group F2, while there was no difference between the control and Group F1 regarding these parameters. The weight and length of the quality chicks were promoted in the Group F1. In Group F3, the injection of the formula product at a rate of 5% had a negative effect on parameters such as hatchability, embryonic mortality, chick length, Pasgar score and yolk sac weight compared to the other groups. Otherwise, in Group F2, there was a significant increase in villus height, crypt depth and lamina muscularis mucosa thickness compared to the other groups (p<0.01). As a result, it has been concluded that the appropriate rates for the formula product application on chicks are 1.25% and 2.5%, considering the positive effects of the 1.25% and 2.5% rates and the negative effects of the 5% rate.

Modification of the terms of authorisation of the feed additive consisting of canthaxanthin for chickens for fattening, minor poultry species for fattening, laying poultry and poultry reared for laying, ornamental fish and ornamental birds and ornamental breeder hens to include canthaxanthin produced with Yarrowia lipolyticaCBS 146148 (DSM Nutritional Products Ltd.).

Following a request from the European Commission, the European Food Safety Authority was asked to deliver a scientific opinion on the proposed modification of the terms of the authorisation of canthaxanthin, regarding the addition of a new production route, by the yeast Yarrowia lipolytica CBS 146148. The additive is already authorised as sensory feed additive for use in feed for chickens for fattening, minor poultry species for fattening, laying poultry, poultry reared for laying, ornamental fish, ornamental birds and ornamental breeder hens. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concludes that canthaxanthin produced with Yarrowia lipolytica CBS 146148 is considered safe for the target species, the consumer and the environment under the current authorised conditions of use. Canthaxanthin is not an irritant to skin or eyes and it is unlikely to be a skin sensitiser. No conclusion can be reached on the respiratory sensitisation of canthaxanthin. In the absence of data, no conclusions on the safety for the user can be reached for any preparation produced with canthaxanthin. Canthaxanthin produced by fermentation with Y. lipolytica CBS 146148 is efficacious as a colouring agent in feed for chickens for fattening and minor poultry species for fattening, laying poultry and poultry reared for laying, ornamental fish and ornamental birds.

Residual ciprofloxacin in chicken manure inhibits methane production in an anaerobic digestion system

Anaerobic digestion (AD) is commonly used to dispose of laying hen manure. However, veterinary antibiotic residues present in chicken manure may affect the AD process. Here, the effects of three types of veterinary antibiotics commonly used in laying hen breeding on AD were explored. Manures containing antibiotics at two different concentrations were continuously added during AD for 5 days: amoxicillin (HAMX: 145.06 mg/kg, LAMX: 57.88 mg/kg), doxycycline (HDOC: 183.61 mg/kg, LDOC: 98.00 mg/kg), and ciprofloxacin (HCIP: 96.34 mg/kg, LCIP: 40.43 mg/kg). Compared with a control with no veterinary antibiotics, the amoxicillin and doxycycline groups presented no significant effects on biogas production, methane production, VFA concentration, acetic acid concentration or the pH of the AD system (P > 0.05). However, compared with the control, the ciprofloxacin groups presented significantly inhibited biogas and methane production during AD (P < 0.05), and the HCIP and LCIP groups presented significantly decreased biogas (47.82% and 45.37%, respectively) and methane (58.24% and 52.55%, respectively) production (P < 0.05). Moreover, the VFA and acetic acid concentrations of the ciprofloxacin groups were significantly higher than those of control during the entire AD period (P < 0.05), and the pH value at the withdrawal stage was significantly lower than that of the control group (P < 0.01), with no significant difference between the HCIP and LCIP groups (P > 0.05). Our results suggest that ciprofloxacin causes VFA and acetic acid accumulation in AD systems, thereby reducing the pH of the systems and inhibiting methanogen growth, ultimately reducing methane production in the AD systems. These findings contribute to a deeper understanding of the impact of ciprofloxacin on methane production in AD systems and offer some considerations for the application of AD systems.

In Vitro and In Vivo Evaluation of the Fertilization Capacity of Frozen/Thawed Rooster Spermatozoa Supplemented with Different Concentrations of Trehalose.

The objective of this study was to evaluate the impact of the supplementation of varying concentrations of the impermeable disaccharide trehalose on the in vitro and in vivo fertilization capacity of cryopreserved rooster spermatozoa in the original Czech Golden Spotted Hen breed. The control trehalose concentration was 0 mM, while TRE50 (50 mM), TRE100 (100 mM), and TRE200 (200 mM) were used as experimental trehalose concentrations. The kinematic and functional parameters of frozen/thawed spermatozoa were evaluated in vitro using mobile computer-assisted sperm analysis and a flow cytometer. The addition of 100 mM trehalose demonstrated the most favorable results for total (34.17%) and progressive (3.57%) motility after thawing. A statistically significant difference was found for these kinetic parameters compared to the other monitored concentrations. This experimental group was also found to have a significantly higher percentage of spermatozoa without plasma membrane or acrosome damage (33.37%) compared to the TRE50 group (30.74%; p < 0.05) and the TRE200 group (29.05%; p < 0.05). In vivo, artificial insemination was performed to verify fertilization ability. Hens (n = 40) were artificially inseminated twice (10 hens/treatment) with a 3-day interval between inseminations. In conclusion, the addition of 100 mM trehalose significantly improved total and progressive motility after thawing and preserved plasma membrane and acrosome integrity (p < 0.05). The fertilization rate of eggs fertilized with semen frozen with the addition of 100 mM trehalose was not significantly different from the other concentrations tested or the control group but was numerically higher (23.21% vs. 15.20% of fertilized eggs in this group).

Utilization of Bone Alkaline Phosphatase (BAP) and Tartrate Resistant Acid Phosphatase (TRAP) as Biomarkers of Eggshell Quality and Bone Metabolism in Broiler Breeders and Progeny.

Eggshell breakage and broiler bone disorders are major problems for the breeder and broiler industries which are linked to mineral metabolism and animal genetics. The purpose of this work was to discover the link between individual animal phenotypic differences in mineral metabolism against concentrations of novel plasma biomarkers including tartrate resistant acid phosphatase (TRAP) and bone alkaline phosphatase (BAP). A subset of hens were selected from a flock of Cobb 500 breeders with the best or worst eggshell quality based upon dual energy x-ray absorptiometry (DEXA) and specific gravity (SG). Breeders were defined as having good eggshell quality (SG ≥ 1.080), or poor eggshell quality (SG < 1.080). Progeny hatched from breeders with good or poor eggshell quality were reared to 2 week of age and blood and bone samples were obtained after euthanasia. In both breeders and progeny, plasma concentrations of BAP and TRAP were measured, and bone mineral density was evaluated by DEXA. Results showed that breeders selected for eggshell quality had significantly different plasma concentrations of BAP (Good = 326.5 pg/mL, Poor = 253.2 pg/mL), and TRAP activity (Good = 2203 U, Poor = 4985 U). Breeders selected for eggshell quality produced progeny with different bone breaking strength (Good = 1.61 kg/mm, Poor = 1.47 kg/mm), tibia ash (Good = 45.9%, Poor = 42.2%), plasma BAP (Good = 372.3 pg/mL, Poor = 312.4 pg/mL), and lower plasma TRAP activity (Good = 18010 U, Poor = 23590 U). These data suggest that there is a strong correlation between the eggshell quality of breeders, performance and bone strength of progeny, and plasma of concentrations of BAP and TRAP in both breeder hens and progeny.

Performance of local breed hens (Gallus gallus domesticus) in two agro-ecological zones of Madagascar (High plateaus-south and south-east)

Performance of local breed hens (Gallus gallus domesticus) in two agro-ecological zones of Madagascar (High plateaus-south and south-east)

25-Hydroxycholecalciferol Improves Cardiac Metabolic Adaption, Mitochondrial Biogenetics, and Redox Status to Ameliorate Pathological Remodeling and Functional Failure in Obese Chickens.

Broiler breeder hens allowed ad libitum (Ad) feed intake developed obesity and cardiac pathogenesis and thereby were susceptible to sudden death. A supplement of 69 µg 25-hydroxycholecalciferol (25-OH-D3)/kg feed rescued the livability of feed-restricted (R) and Ad-hens (mortality; 6.7% vs. 8.9% and 31.1% vs. 48.9%). Necropsy with the surviving counterparts along the time course confirmed alleviation of myocardial remodeling and functional failure by 25-OH-D3, as shown by BNP and MHC-β expressions, pathological hypertrophy, and cardiorespiratory responses (p < 0.05). 25-OH-D3 mitigated cardiac deficient bioenergetics in Ad-hens by rescuing PGC-1α activation, mitochondrial biogenesis, dynamics, and electron transport chain complex activities, and metabolic adaptions in glucose oxidation, pyruvate/lactate interconversion, TCA cycle, and β-oxidation, as well as in TG and ceramide accumulation to limit lipotoxic development (p < 0.05). Supplemental 25-OH-D3 also sustained Nrf2 activation and relieved MDA accumulation, protein carbonylation, and GSH depletion to potentiate cell survival in the failing heart (p < 0.05). Parts of the redox amendments were mediated via lessened blood hematocrit and heme metabolism, and improved iron status and related gene regulations (p < 0.05). In conclusion, 25-OH-D3 ameliorates cardiac pathological remodeling and functional compromise to rescue the livability of obese hens through metabolic flexibility and mitochondrial bioenergetics, and by operating at antioxidant defense, and heme and iron metabolism, to maintain redox homeostasis and sustain cell viability.

Transcriptome analysis of jejunal mucosal tissue in breeder hens exposed to acute heat stress

Heat stress (HS) severely compromises intestinal barrier function in poultry, resulting in significant production losses. This study aimed to explore the molecular response of the small intestine to acute HS in breeder hens. Fifty 28-week-old breeder hens were raised individually in a cage and randomly assigned to control and heat-treated groups (25 hens each). Control group hens were maintained at thermoneutral conditions (23°C) and heat-treated group hens were subjected to acute HS (36°C for a 6-h). The heart rate and cloacal temperature were measured in all hens. The jejunal mucosa tissues were collected from 12 randomly selected hens per group for transcriptomic analysis. The acute HS induced significant physiological alterations, with a marked increase in the heart rate and cloacal temperature in hens (P = 0.001). Transcriptome analysis revealed 138 genes with altered expression patterns under acute HS conditions. Of these, 75 genes including heat shock proteins (HSPs) showed upregulated expression, while 63 genes including a key bile acid transport molecule (SLC10A2) exhibited downregulated expression. Functional analysis through gene ontology classification, pathway mapping via the Kyoto encyclopedia of genes and genomes, and protein interaction networks identified several important regulatory genes in thermal response (HSPA8 and HSPA2), energy homeostasis and fat metabolism (PDK4, PPARA, and CD36), glucose transport (SLC2A5), and cholesterol synthesis pathway (SQLE, CYP51A1, and HSD17B7). The findings suggest that acute HS might affect energy utilization, fat metabolism, and glucose transport mechanisms in the jejunal mucosa of breeder hens. The upregulation of HSPs appears to serve as a protective mechanism, potentially preserving intestinal nutrient processing capacity under acute HS. These findings provide foundational knowledge for further investigation into the molecular mechanisms governing HS responses in avian intestinal function and may inform strategies for maintaining gut health in commercial poultry operations exposed to environmental challenges.

Effects and interactions of dietary lysine and apparent nitrogen corrected metabolizable energy on yellow-feathered broiler breeder hens

BackgroundDietary lysine and apparent nitrogen-corrected metabolizable energy (AMEn) are two key variables affecting the production of breeder hens. In this study, the effects and interactions of lysine and AMEn on yellow-feathered broiler breeder hens were investigated. A total of 720 30-week-old breeder hens were fed in a 5 (lysine: 0.56%, 0.68%, 0.80%, 0.92%, and 1.04%) × 2 (AMEn: 11.50 and 11.10 MJ/kg) factorial arrangement for 12 weeks. The productive performance, reproductive traits, biochemical variables of breeder hens, the amino acid concentration and quality of eggs, and the growth performance of offspring broilers were determined.Result(1) Dietary lysine had quadratic effects (P < 0.05) on laying rate, average daily egg mass and feed intake/egg mass of breeder hens; birds with 11.50 MJ/kg AMEn (high AMEn) had higher (P < 0.05) BW than those with 11.10 MJ/kg AMEn (low AMEn); (2) dietary lysine significantly affected on the relative ovarian weight (quadratic and linear), and numbers of large yellow follicles (LYF, quadratic); birds with high AMEn had longer fallopian tube and more LYF than those with low AMEn (P < 0.05); (3) dietary lysine had significant effects (linear and quadratic) on eggshell thickness and shell strength of eggs from breeder hens; birds with high AMEn had thinner eggshells and deeper yolk color than those with low AMEn (P < 0.05); (4) there were higher (P < 0.05) contents of protein and concentrations of all measured animo acids (AAs) in eggs from birds fed low AMEn; (5) supplementation with high AMEn to breeder hens significantly increased the hatchability of fertilized eggs; (6) neither dietary lysine level or AMEn affected growth performance of offspring broilers; (7) both dietary lysine level and AMEn significantly affected gonadotropin concentrations and biochemical variables of breeder hens.ConclusionsDietary lysine had significant influences on productive performance, reproductive traits, and egg quality of yellow-feathered breeder hens. Based on productive performance, the optimal levels of dietary lysine were 0.81% to 0.83%, while 0.71% to 72% lysine was enough to obtain the best quality of breeding eggs. High AMEn was more beneficial to breeder hens for reproductive traits and hatchability of the fertilized eggs, while it showed detrimental effects on eggshell thickness and AA concentrations of breeding eggs.

Maternal Supplementation of Collagen Peptide Chelated Trace Elements Enhances Skeletal Muscle Development in Chicks.

Maternal nutrition plays an important role in regulating the growth and development of offspring. Collagen peptide chelated trace elements (PTE), as a new additive, have been proven to have a positive maternal effect on the intestinal health of offspring, but its effect on the growth anddevelopment is still unclear. This study aimed to investigate the effect of maternal PTE supplementation on the skeletal muscle development of offspring. A total of 270 breeder hens were randomly divided into 3 groups, and fed basal diet (CON), basal diet + 500mg/kg PTE (L-PTE), and 1000mg/kg PTE (H-PTE) for 8weeks. A total of 180 eggs were collected from each group for incubation, and then the hatched male chicks (6 replicates, 12 chicks/replicate) were allocated according to maternal treatment for a 14-day feeding experiment. The results showed that maternal PTE supplementation significantly increased the deposition of iron (Fe), zinc (Zn), and manganese (Mn) in the egg yolk (P < 0.05). In comparison with the CON group, the body weight (days 1 and 14), breast muscle weight (day 14), and muscle fiber density (day 14) of broilers were increased in the L-PTE group (P < 0.05). The serum creatinine (CREA) levels in 1-day-old broilers were reduced in the L-PTE group and H-PTE group(P < 0.05). Additionally, maternal PTE supplementation could upregulate the relative expression level of catalase (CAT) mRNA in breast muscle (P < 0.05). The relative mRNA levels of hemeoxygenase-1 (HO-1) and superoxide dismutase 1(SOD1) in the H-PTE group were significantly upregulated (P < 0.05). Moreover, PTE treatment upregulated the mRNA expression of skeletal muscle development-related genes (Pax7 and MyoG) and the IGF signaling pathway (mTOR, IGF-1R, and IGF-2R) (P < 0.05). In conclusion, maternal PTE supplementation may improve the growth performance and skeletal muscle development of offspring by activating the IGF signaling pathway.

Alleviating heat stress on broiler breeder hens: Effect of dietary antioxidant supplementation on reproductive performance, egg quality, offspring growth, and antioxidant capacity

Alleviating heat stress on broiler breeder hens: Effect of dietary antioxidant supplementation on reproductive performance, egg quality, offspring growth, and antioxidant capacity

In ovo injection of organic zinc effects on hatching rate of broiler breeder hen eggs and productivity of broilers

The aim of this study was to investigate the effect of in ovo injection of organic zinc on the characteristics of broiler chickens and the performance of broiler chickens A total of 320 eggs from Ross 308 strain with an average weight of 65 grams were randomly divided into four groups, negative control (no injection), positive control (in ovo injection of 0.272 ml of normal saline solution) and two experimental groups, eggs in the first received in ovo injection of 0.272 mg of organic zinc whereas in the second the eggs were injected with 0.544 mg of the same organic zinc. The injection was done in the amniotic sac on the 10th day of incubation. The effect of injection on hatching traits and then on functional traits, blood parameters, immune response, carcass characteristics and cecal microbial population of resulting broilers were measured. The results showed that the percentage of hatched broiler chickens in the zinc-treated groups was significantly lower compared to the two control groups. However, the intraocular injection of zinc caused a significant increase in the final weight gain of the birds and their feed consumption. Blood parameters were also affected in experimental treatments and blood glucose increased and blood triglyceride, cholesterol and lipoproteins decreased compared to negative and positive control (P&lt;0.01). On the other hand, no statistically significant difference was observed in the immune response, microbial population and carcass characteristics among the experimental groups. In conclusion, the intra egg injection of organic zinc can show favorable results in the performance indicators of broiler chickens, although it had no effect on the immune response and microbial population.

Molecular tool for efficient breeding of DOMINANT Greenshell laying hens and significant refinement of phenotypic selection focused on eggshell color

In recent decades, interest in non-traditionally colored eggs has increased. For breeders, this market interest means breeding lines of laying hens that lay eggs of varied colors, such as the blue-green eggshells (Dominant Greenshell) in this study. This study presents the results of genotyping the polymorphism of the O locus responsible for shell coloration and photometric measurement of eggshell color based on the CIELAb system, which was carried out on the unique Czech breeding population Dominant Greenshell. The aim was to use a combination of phenotyping using the CIELab System method and genotyping of the O locus using the end-point PCR approach with the main focus on the accuracy of distinguishing shell color genotypes, streamlining the selection of dominant homozygotes in the O locus, optimizing this technology for the most efficient and cost-effective selection procedure in practical hen breeding. The optometric method was able to reliably distinguish only dominant and recessive phenotypes and eliminate from the population only undesirable recessive homozygotes with a white colored shell. The parameter a* (redness/greenness) from the CIELab color space turned out to be absolutely key for distinguishing dominant and recessive phenotypes. Using the CART methodology, a classification tree built on discriminating optometric characteristics a-blunt was obtained, however, for the group of desirable O/O homozygotes, the selection approach would result in incorrect genotyping of 31% of individuals. Therefore, a combined approach based on rapid and simple elimination of recessive homozygotes using phenotyping (CIELab photometric measurement) and molecular identification of the EAV-HP insertion in the SLCO1B3 gene in dominant phenotypes, regardless of color intensity affected by laying time/order, and allowing reliable elimination, has proven to be the most effective method to distinguish heterozygotes from the breeding population. The combination of optometric and molecular selection methods then leads to more efficient selection, reduction of overall selection costs. This process led to the stabilization of the breeding population within one generation and the achievement of a pure homozygous line with regard to eggshell color.

Body weight optimization of broiler breeder hens. 1. Pullet growth, feed efficiency, carcass composition, and sexual maturation

This study aimed to evaluate the effect of early growth (EG) and time of maximum pubertal growth peak (I2) on development, feed efficiency, carcass composition, and sexual maturation of broiler breeder females. Target BW trajectories were designed by changing coefficients of a 3-phase Gompertz model fit to the recommended BW target of Ross 308 breeders, BW=∑i=1i=3giexp(−exp(−bi(t−Ii))). In each phase i, biologically relevant coefficients describe the amount of BW gain (gi), the rate of growth (bi), and the inflection point (Ii), which is the time when the growth rate for that phase is at its maximum rate. The study consisted of a 6 × 2 factorial arrangement, with six I2 levels (I from phase 2) and two EG levels. The I2 coefficients were 15, 17, 19, 21 (standard), 22, and 23 in wk. The EG treatments were: EG0, where g1 and g2 coefficients estimated from the standard from the breeder recommended BW were unchanged; and EG20, where 20% of the gain (g2) in phase 2 (pubertal phase) was shifted to phase 1 (g1; prepubertal phase). Two-hundred-eighty-eight Ross 308 pullets were randomly assigned to the twelve BW growth trajectories and fed using a precision feeding system from 0 to 28 wk of age. Body composition variables were submitted to three-way ANOVA, with EG, I2, and age as fixed sources of variation. Analysis of covariance was conducted on the remaining dependent variables with EG as fixed effect, I2 as a continuous fixed effect, and age as continuous random effect. Differences were reported at P ≤ 0.05. The BW of females followed their target BW, and ADFI differed depending on the amount of feed required to achieve their respective BW targets. Breast fleshing score was 0.2 greater in the EG20 compared to EG0. The number of juvenile primary wing feathers and age at first egg decreased by 0.4 and 0.9 d, respectively, per wk of earlier I2. Advancing I2 resulted in birds with increased carcass fat deposition from 16 to 28 wk of age. Carcass fat was 1.3- to 1.6-fold greater in the EG20 only from 4 to 16 wk of age. Early growth increased mostly pullet muscle and skeletal characteristics whereas advancing I2 advanced sexual maturity and increased carcass fat deposition around sexual maturation time.