Commercial Layer Research Articles

Transcriptome analyses of shell color and egg production traits between the uteruses of blue-green eggshell chickens and Hy-Line brown layers

Blue-green eggs exhibit unique shell color; however, compared to commercial layers, blue-green eggshell chickens have lower egg production and lack uniform shell colors. Aiming to confirm the molecular mechanisms that affect shell color and egg production, this study collected the uteruses of 12 blue-green eggshell chickens (BG group) and six Hy-Line layers (Brown group), which had significantly different shell color indexes (SCI) and egg numbers at 300 days of age (EN300). Transcriptome sequencing and comparative analyses were subsequently performed. BG hens were divided into two groups for comparative analysis (BGblue vs. BGgreen and BGlow vs. BGhigh, respectively), based on the differences in SCI and EN300, respectively. The result of weighted gene co-expression network (WGCNA) analysis showed that the sequenced and mapped 16,785 genes were clustered into 18 modules, among which six modules with a total of 4270 genes were highly correlated with SCI and EN300 traits. Five hundred and eleven differentially expressed genes (DEGs) belonged to the six key modules. Through KEGG mapping, GO enrichment, and Cytoscape network analysis, nine Hub genes were tightly associated with SCI and EN300. The up-regulated genes were CCR2, CCR8, CD40LG, IL18RAP, INHBA, and P2RY13, while the down-regulated genes were ABCA13, ADCY2, and GRM1. Co-analyses with the results of comparisons between the BG subgroups revealed that the expression of solute carrier (SLC) proteins and ABC transporters were highly related to eggshell color, while cytokine-cytokine receptor interactions and neuroactive ligand-receptor interactions were key pathways affecting egg production. The expression of extracellular cytokines and membrane receptors were significantly up-regulated in low-yield chickens. The candidate DEGs and pathways found in the study will assist in clarifying the molecular mechanisms affecting shell color and egg production, and improve the breeding of blue-green eggshell chickens.

Tissue oxidative stress and expression of chicken UCP and ANT mRNA in laying hens exposed to acute cold stress

ABSTRACT 1. Exposure to stress alters normal homoeostasis and, hence, the antioxidant defence system. The aim of this study was to examine the effect of acute cold temperature on the antioxidant defence system in hens. 2. Hy-line grey commercial layers (80 40-week-old) were randomly assigned to one of eight groups. In groups 1 to 5, hens were exposed to low temperature at −8.68°C (cool stressed) for 2, 4, 6, 8 and 10 h, respectively. In groups 6 and 7, post 10 h cool stressed, hens were quickly transferred to room at 21°C to recovery for 2 h and 4h, respectively. In treatment groups 6 and 7, post 10 h cool stressed, hens were quickly transferred to room at 21°C for 2 h and 4 h, respectively. Group 8 was the control, where hens were housed under regular condition at 21°C as controls. 3. Antioxidant enzymes (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GPx) and malondialdehyde (MDA), in skeletal muscle, the kidney, liver and pancreas were measured. The transcription of avUCP and ANT mRNA was tested by RT-PCR. 4. The T-AOC activity was increased in the skeletal muscle of hens cold stressed for 2, 4, 6, 8 and 10 h and the 2 h recovery groups compared with control hens (p < 0.05). The GPx activity was increased in the liver and skeletal muscle after cold stress 4 h and in the pancreas of cold stress 2 h compared with the control group (p < 0.05). Antioxidant SOD activity was increased in the kidney after cold stress 6 h and in the liver after cold stress 10 h compared to the control group (p < 0.05). Measured MDA activity was increased in the pancreas after 2 h cold stress (p < 0.05). 5. UCP mRNA expression level was increased in the pectoral muscle for 2 h and 4 h recovery groups compared with the control hens (p < 0.05) and avian uncoupling protein (UPC), adenine nucleotide translocator (ANT) expression level was increased in the leg muscle of hens cold stress for 2, 6, 8 h and recovery 2 and 4 h. 6. The observed changes in the antioxidant defence system were tissue specific. Increments in levels of ANT (leg muscle) and UCP (pectoral and leg muscle) mRNA expression may be involved in the regulation of thermogenesis in skeletal muscle.

Influence of Seasons on Production Performance of Commercial Layer Chicken in Southern Region of Telangana

Background: Effective management strategies and feeding practices are essential for mitigating the challenges presented by the extreme temperatures of the summer season and the increased humidity and disease risk during the wet season. Adapting to these seasonal variations is crucial for maintaining a successful and profitable layer chicken farming. Methods: Influence of seasons (summer, rainy and winter) on production performance of layer chickens in different production cycles (Phase I, II, III and IV) was studied. The commercial layer chicken farms from southern Telangana region were selected with bird capacities ranging from 1.0 to 1.5 lakhs, rearing BV-300 breeds, aged 19-83 weeks, housed in elevated cage systems were randomly chosen. The data was collected from farm records, pre-structured questionnaires and personal interviews. Result: Summer (Phase I: 19-30 weeks) showed decreased egg production (70.57%), increased broken eggs (1.50%) and lower livability (99.95%). Egg production showed improved performance during the winter (90.22%) and rainy seasons (89.40%) in Phase II (31-50 weeks), highlighting the importance of seasonal adjustments for enhancing productivity. Phase III (51-72 weeks) also demonstrated rainy and winter seasons consistently yielding better results, with rainy season notably excelling in higher egg production (89.70%). Phase IV (72 weeks and above) highlighted winter’s superiority in egg production (79.70%) and reduced broken eggs (0.57%), emphasizing the importance of adapting poultry farming practices to mitigate the climatic variability.

Assessment of positive experiences using associative learning in chickens

To determine whether differences in positive experiences can influence associative learning ability, 2 tasks were conducted with 90 laying hens at the peak of the laying period. The selected hens were reared in a larger flock under the same housing conditions without perches, so they had the same rearing experiences and were moved to either enriched cages or to the floor system at 16 wk of age. They belonged to 3 breeds (Slovenian barred hen: Ba; brown hen: Br; silver hen, S), with 30 hens per breed. The predictor signal, the sound of a clicker, with a 3-second delayed reinforcer (commercial layer feed) was used to mark the desired behaviour (pecking for feed). Hens that associated feed with a clicker (85.06%) were taught 2 tasks, the colour discrimination task (CD) and the target following task (TF). In the CD, the hens had to discriminate between yellow, red and blue colors and peck at a yellow magnet only. In the TF, the desired behaviour was to follow a target, a purple ball on a stick, from 1 perch to another and peck it at the end of the perch. The main results of the hens associating the signal with feed were that the Ba hens learned faster than the S hens (P = 0.006) and required fewer clicker sounds than the Br hens in the CD (P = 0.003). Floor hens that completed CD or TF or both took less time to complete the task (CD, P = 0.03, TF, P = 0.06; both tasks, P = 0.02) or with fewer clicker sounds (CD task; P = 0.02) than cage hens. Although these results suggest that Ba hens and floor hens showed better associate learning performance, probably because they perceived their environment as more rewarding and thus potentially more positive, caution is needed in interpretation considering social experiences and that the ability to perch and the ability to move quickly on a perch can be confounded in TF and both tasks can be confounded with foraging ability.

Financial impact of low pathogenic avian influenza virus subtype H9N2 on commercial broiler chicken and egg layer production systems in Pakistan

Low Pathogenic Avian Influenza (LPAI) subtype H9N2 is endemic in Pakistan and impacts poultry farming through disease related mortality, poor weight gain and reduced egg production. This study aims to estimate the farm-level financial impact of LPAI H9N2 infection on commercial broiler and layer production systems in Pakistan.A questionnaire based cross-sectional survey of 138 broiler farms and 136 layer farms in Pakistan was conducted in 2019. Primary data collected by cross-sectional survey along with expert opinion and published literature were used to parameterize five stochastic production and gross margin models for three broiler and two layer production systems: fully integrated production (FIP), partially integrated production (PIP) and independent farming production (IP) systems. Partial budget analysis were then carried out to estimate the financial impact of LPAI H9N2.Results indicate that in broiler production systems, starting with 35,000 day old chicks (DOC) per batch, the net cost of disease (million PKR/production cycle) was estimated at 4.10 (14,862 USD), 4.62 (16,747 USD) and 2.46 (8917 USD) for IP, PIP and FIP systems, respectively. The disease produced a negative gross margin (defined here as revenue minus replacement and variable costs) in IP (-53 PKR (-0.19 USD)/DOC bought) and PI (-25 PKR (-0.091 USD)/DOC bought) systems, while remained positive for FIP systems (87 PKR (0.32 USD)/DOC bought). For layer production systems, (mean flock size as 48,000 DOCs) the net cost (million PKR/production cycle) was 29.75 (107,095.21 USD) and 29.51 (106,223.45 USD) IP and PIP systems, respectively, and produced negative gross margin in both systems.The outcomes of the study highlight the vulnerability of independent and partially integrated production systems to the disease. These findings also offer a decision-making tool to the farmers and policy makers to evaluate avian influenza surveillance systems and control interventions in Pakistan.

390 Investigating the cecal microbiota of commercial layers raised in different production systems

390 Investigating the cecal microbiota of commercial layers raised in different production systems

Effect of fiber curvature on gas diffusion layer two-phase dynamics of proton exchange membrane fuel cells

Both straight and curved carbon fibers are widely used in various commercial gas diffusion layer (GDL) fabrications. The effect of the different carbon fiber curvatures on two-phase flow dynamics within the cathode GDLs of proton exchange membrane fuel cells remains unclear. In this study, we investigate liquid transport in three types of GDLs with varying fiber curvatures using the two-phase volume of fluid simulations in OpenFOAM. For the first time, a rod periodic surface model is combined with a layer-by-layer fiber stacking strategy, to stochastically reconstruct GDL structures while incorporating crucial parameters from physical (experimental) GDLs. A grid independence study and model validation are conducted. Following pore network analysis of pore size distribution and connectivity, we study the time-varying GDL total and local water saturation and capillary pressure. Despite maintaining similar layer and bulk porosity, increased fiber curvature enhances pore connectivity but raises water saturation and capillary pressure, increasing the risk of flooding. Additionally, droplets in gas channels with straight-fiber GDLs are larger and have slower movement than those in curved-fiber GDLs. Fiber curvature inversely affects drainage capacity in GDLs and connected channels. With comparable water saturation and capillary pressure, curved-fiber GDLs exhibit lower discrepancies, suggesting improved uniformity in water distribution.

Cocirculation of Newcastle Disease Virus Genotypes XII and VII Along with Nonvirulent Forms Characterized in Domestic Birds from Peru.

Newcastle disease virus (NDV) is one of the most important pathogens affecting poultry, given its impact on health and production systems worldwide, despite widespread vaccination. Over the past 20 years, NDV has caused severe outbreaks of disease in Peru. These outbreaks primarily affected gamecocks and broiler chickens, with an additional reported case in commercial layers. Therefore, our objective was to identify and characterize the virus responsible for these cases in Peru. We analyzed 14 suspected clinical cases in domestic birds for NDV detection, isolation, and genetic characterization. Among these cases, seven involved gamecocks, with six genotype XII isolates and one genotype VII isolate, representing the first report of NDV genotype VII isolate from fighting roosters in Peru. Additionally, among the six cases in broiler chickens, we detected four genotype XII isolates and three genotype II isolates, including one sample containing both genotypes XII and II. Furthermore, a genotype I viral isolate was identified in a laying hen. Hence, we concluded that two divergent, highly virulent NDV genotypes, genotypes XII and VII, along with avirulent forms such as genotypes I and II are circulating among domestic birds in Peru. Genetic analysis indicates that these viruses are evolving locally within avian species and offers the basis necessary for vaccine adaptation to circulating viruses. Our results highlight the cocirculation of multiple virulent and nonvirulent NDV genotypes in domestic birds in Peru, underscoring the potential role of gamecocks as a viral source of virulent NDV strains in the country and the occurrence of outbreaks in poultry farms.

Electrochemical Reduction of CO2 to Multi-Carbon Products on Sputtered Cu Nanoparticles Gas Diffusion Electrodes

The electrochemical reduction of CO2 is a technology of great environmental and economic interest as it provides a promising solution for reducing the concentration of CO2 with producing valuable chemical compounds. Cu and its alloys have attracted much attention because of their moderate CO binding energy for reducing CO2 to multi-carbon (C2+) products[1]. The reactivity and product selectivity of the CO2 reduction reaction (CO2RR) depend on the interfacial structure and the nano-scale morphology of the catalyst as well as on the catalyst material composition. Especially for the gas diffusion electrodes (GDEs), the catalyst morphology has a significant influence on the formation of triple-phase boundary that increases CO2 reactivity and product selectivity[2,3]. However, the influence of catalyst morphology including catalyst thickness, porosity, particle size on CO2RR has not been fully understood yet because of the complex CO2RR mechanism and catalyst structure in GDEs. In this study, we investigated the relationship between product selectivity and the thickness of the Cu controlled by sputtering techniques and characterized nanostructure of the Cu-GDEs.The Cu catalyst layer (CL) was deposited on a commercial carbon-based gas diffusion layer (GDL) with a micro porous layer (MPL) by magnetron sputtering from a pure Cu target at room temperature. The geometric area of the deposited Cu was 0.5 cm2. The nanostructures of GDEs were evaluated using scanning transmission electron microscopy equipped with energy dispersive X-ray analyzer (STEM-EDX). Electrochemical experiments were carried out in a three-electrode setup using a Biologic-VSP instrument. A home-made three-compartment flow cell was used with the Cu-GDE as the working electrode between the gas and cathode compartments. An Ag/AgCl electrode was placed in the cathode compartment as the reference electrode and a Pt mesh as the counter electrode in the anode compartment. 1 M KCl was used as the catholyte, saturated KHCO3 was used as the anolyte and a proton exchange membrane (Nafion 117) was used to separate the anode and cathode compartments. The CO2 gas flow to a gas compartment was kept at 30 sccm. Electrochemical CO2RR was performed by chronopotentiometry. The gas products were quantified using a gas chromatography with thermal conductivity detector. As for the liquid products, alcohols were evaluated using a gas chromatography with flame ionization detector and organic acids were detected by high performance liquid chromatography with conductivity detector, respectively.The faradaic efficiencies (FEs) of CO2RR products using GDEs with various CL thickness of 70, 300, 1000, 2000 nm were measured under current density of 400 mA cm-2. The GDE with CL thickness of x nm is written as CLxGDE. The major gas and liquid products for all the GDEs were ethylene and ethanol with the FE of around 37-42% and 26-31%, respectively. As decreasing CL thickness from 2000 nm, FEs for C2+ products (FEC2+), such as ethylene, ethanol, n-propanol etc., were increased from that of CL2000GDE of 69%. The maximum FEC2+ reaching 81% was achieved for CL300GDE. The FEC2+ for CL70GDE was slightly decreased down to 76%. In comparison with the FEs for CL2000GDE, the FEs of ethylene, ethanol, and n-propanol were each increased by 2-5%, while FE of H2 was decreased for CL300GDE.To clarify the details of CL morphology, the surface structure of CL300GDEs was observed before and after the CO2RR measurement using STEM-EDX. Figures (a) and (b) show cross-sectional images of nano-scale annular dark field (ADF)-STEM and EDX mapping (purple color show Cu and cyan blue color show C) before the CO2RR measurement. The Cu layer was uniformly stacked on MPL with the designed thickness of 300 nm. Figures (c) and (d) show cross-sectional images of ADF-STEM and EDX mapping after the CO2RR measurement. Cu nanoparticles less than 50 nm were distributed on the surface and inside of the MPL. The stacked Cu layer as observed before the CO2RR measurement was not observed after the CO2RR. These results indicate that Cu atoms migrate during the CO2RR and distributed Cu nanoparticles exhibit the high FEC2+. We will discuss the influence of Cu migration during the CO2RR on product selectivity from the results of synchrotron-based analysis and nanostructure observation in the presentation.[1] A. Bagger et al., ChemPhysChem. 2017, 18, 3266-3273.[2] N. T. Nesbitt et al., ACS Catal. 2020, 10, 14093-14106.[3] A. Inoue et al., EES Catal. 2023, 1, 9–16.Fig. Cross-sectional images of (a), (c) ADF-STEM and (b), (d) EDX mapping before and after CO2RR for CL300GDEs, respectively. Purple color show Cu and cyan blue color show C. Figure 1

Research note: differential heterosis of spent laying hens’ carcass characteristics and meat quality in reciprocal crosses between White Leghorn and Beijing-You chickens

Hybridization is used extensively in commercial layer production. However, heterosis for carcass performance and meat quality of spent laying hens remains unclear, especially under the trend of extended laying cycles. In this study, indigenous Beijing-You chickens (Y) and elite White Leghorn layers (W) were selected to generate purebreds (WW and YY) and reciprocal crosses (WY and YW). Data on traits including carcass compositions, meat quality, and main nutrients for breast muscle were collected when chickens fed to 100 wks of age. Results showed that body weight (BW) and dressed weight for WY and YW with positive heterosis were significantly higher than WW (P < 0.05). YW had the heaviest breast and thigh of 232.28 g and 278.48 g, respectively. The abdominal fat weight for WY and YW were greatly higher than that for WW (P > 0.05). The yields of carcass compositions, including the dressed yield, half eviscerated yield, eviscerated yield, breast yield and thigh yield, did not differ among four genetic groups (P > 0.05), except for the yield of abdominal fat. The largest heterosis differences appeared in breast weight (12.26% in YW v.s. -0.46% in WY) and abdominal fat yield (15.26% in YW v.s. 24.55% in WY). Although BW for crossbreds were similar, the specific parts of the carcass between them were different. For meat quality, WY had negative heterosis (P < 0.05) with the lowest lightness and yellowness, whereas YW had the completely opposite trend. Neither pH1h nor pH24h values had difference among purebreds and reciprocal crossbreds (P > 0.05). The drip loss and cooking loss were 4.01%-4.77% and 15.59%-21.31% respectively among four genetic groups. The main nutrients of breast, including moisture, crude protein, intramuscular fat and unsaturated fatty acid, did not differ for purebreds and crossbreds (P > 0.05), except for saturated fatty acid. In general, the crossbreds even at the later laying period still showed divergent heterosis on carcass performance and meat characteristics. In view of the heterosis, Beijing-You chickens can use as the sire line in the crossbreeding to improve carcass compositions of spent hens.

Yeast cell wall supplementation affects the Salmonella enteretidis load in the ceca and ovaries of layer pullets

Salmonella enteretidis (SE) has a great propensity to translocate from the cecum into internal organs such as the spleen and liver. However, a major concern is the ability of SE to colonize the ovaries. This study aimed to evaluate the efficacy of cell walls from Saccharomyces cerevisiae to control the Salmonella load in the ceca and ovaries of commercial layer pullets. Ten-week-old layer pullets were divided into 2 groups: one group was fed a control diet with commercial feed without additives, and another group was fed the same diet supplemented with 0.5 kg/metric ton of yeast cell walls (YCWs). At 16 wk of age, the birds in both groups were challenged with 3.0 × 109 CFU/mL SE by oral gavage. The birds were euthanized on d 7 and 14 postchallenge to collect the ceca and ovaries for Salmonella load determination. The results demonstrated that there were no statistical differences in ovary SE infection rates. The trend in the prevalence of SE positivity in the ovaries was similar at 14 d, with 2.1% (YCW pullets) to 4.2% positive for the ovaries of the nontreated pullets. There was also no significant difference in the SE log10 MPN/gram between the YCW and the control groups. In the ceca, the high level of SE (3.0 × 109 cfu/pullet), which results in ovarian transmission, causes high intestinal tract inflammation. There was a significant difference in the prevalence of SE in the ceca at 7 d postchallenge but not at 14 d postchallenge. In conclusion, the reduction in Salmonella load observed in the ceca on d 7 in this study shows the potential of YCW supplementation for reducing Salmonella colonization in poultry.

Effects of dietary free fatty acid content and degree of fat saturation on tibia bone properties of laying hens

Acid oils and fatty acid distillates are fat by-products of the refining process of edible oils and are characterized by their high proportion of free fatty acids (FFA). While lipids are essential in poultry diets, their chemical structure may interfere with calcium absorption. Therefore, this study investigated the effects of dietary FFA content and the degree of fat saturation on bone metabolism in commercial layers. For 15-wk, a total of 144 laying hens (19-wk-old) were randomly assigned to 8 treatments (6 replicates with 3 birds each), which were obtained by gradually replacing crude soybean oil (rich in unsaturated fatty acids [UFA]) with soybean acid oil (rich in UFA and FFA), or crude palm oil (rich in saturated fatty acids [SFA]) with palm fatty acid distillate (rich in SFA and FFA). Following a 2 × 4 factorial design, 4 UFA-rich and 4 SFA-rich diets were created with varying FFA content: 10, 20, 30, and 45%. Tibiae (6 birds/treatment) were collected at the end of the trial for the assessment of mineral composition, morphological properties, and mechanical characteristics. The data were analyzed using a 2-way ANOVA with the GLM procedure. Orthogonal polynomial contrasts were employed to determine the linear effect of increasing %FFA, with statistical significance set at P < 0.05. The degree of saturation was found to negatively impact on calcium and phosphorus bone content, with higher levels found in soybean-based diets (P < 0.001). A significant interaction was observed for medullary bone mineral content, showing a linear decrease as the dietary %FFA increased (P < 0.05) in palm diets. In contrast, morphological and mechanical bone traits, total ash content, and cortical bone mineral composition remained unaffected (P > 0.05). These results suggest that the degree of fat saturation exerts a greater impact than FFA content on bone mineral metabolism, supporting the commercial use of fat by-products rich in FFA in laying hen diets, at least during the early stages of the laying cycle.

Immune Responses in the Harderian Gland After Newcastle Disease Vaccination in Chickens with Maternal Antibodies.

Immune responses in the Harderian gland (HG) were characterized after Newcastle disease virus (NDV) LaSota ocular vaccination in antibody-naïve specific-pathogen-free (SPF) chickens and in chickens of commercial origin with NDV maternally derived antibodies (MDA). Ocular LaSota vaccination of 13-day-old white leghorn SPF chickens elicited serum antibody levels that consistently increased 15 days postvaccination, while the specific IgA response in lacrimal fluids was already detectable 10 days after vaccination. Eleven days postvaccination, the relative abundance of B cells, as well as T-helper cells (CD4+) and cytotoxic T cells (CD8+), in HGs was significantly increased, achieving maximum frequencies 16 days postvaccination. In a second experiment, chickens with MDA originating from NDV-vaccinated commercial white leghorn layer breeders, as well as white leghorn SPF chickens, were vaccinated with NDV LaSota. The LaSota virus successfully replicated in periocular tissues and in the trachea both in commercial and control SPF chickens after vaccination at 2 or 15 days of age (DOA). Vaccination at 2 DOA did not induce a serum NDV antibody response in chickens of commercial origin. In contrast, seroconversion was elicited in commercial chickens upon vaccination at 15 DOA, likely associated with waning of MDA. Unlike systemic IgG responses, vaccination at 2 or 15 DOA elicited strong specific IgA responses in lacrimal fluids in commercial chickens. The IgA response was highest 9 days after vaccination and showed a tendency to decline 15 days postvaccination. Commercial chickens vaccinated at 2 DOA showed increased B cells in HG 10 and 16 days postvaccination. The expansion of B cells in the HG in these chickens is consistent with increased IgA levels detected in lacrimal fluids. In contrast, control SPF chickens showed a more limited B-cell expansion in HG and lower IgA levels. Vaccination at 15 DOA also triggered a greater increase of B cells in HGs in commercial chickens than in control SPF chickens. The B-cell response was accompanied by T-helper (CD4+) cell expansion, occurring both in commercial and control SPF chickens. These cells expanded to a lesser extent when vaccination was performed at 2 DOA compared with vaccination at 15 DOA. CD8+ showed significant expansion irrespective of vaccination day and without differences detected between control SPF chickens and chickens with MDA. We conclude that NDV LaSota elicits vigorous humoral and cell immune responses in the HG. Furthermore, unlike the interference shown by MDA on vaccine-induced serum antibody responses, MDA do not interfere with the mucosal immune response of the HG.

Molecular epidemiological studies of Leucocytozoon caulleryi in commercial layer flocks in Southern peninsular India reveal the presence of new subclusters.

The Leucocytozoon parasites are one of the important protozoa species affecting domestic poultry and wild birds. Though there are frequent reports about the incidence of Leucocytozoon in wild birds, the information regarding the occurrence of commercial poultry is underestimated. From October 2015 to August 2022, ailing and dead birds from 39 commercial layer flocks were submitted to the Poultry Disease Diagnosis and Surveillance Laboratory, Namakkal, with a history of brief illness, followed by mortality with oozing of blood from oro-nasal orifice. The presence of Leucocytozoon caulleryi was confirmed in all the flocks by laboratory examination and PCR. All the Leucocytozoon-positive cases were reported after heavy rainfall and the affected farms were inhabited with Culicoides flies. The infected birds were dull and depressed, exhibited labored breathing, and blood-tinted ropy mucous from the oro-nasal cavity. Necropsy examination revealed pale-anaemic comb and wattles, massive haemorrhagic clot over the surface of the kidney, peritoneum, and trachea, and scattering of greyish-white/reddish military megaloschizonts throughout the serosa of viscera and skeletal muscles. Histopathological examination revealed many spherical cysts or megaloschizonts in the intestine, pancreas, gizzard, spleen, liver, kidney, heart, and breast muscles. The cysts were deeply seated within the above organ's parenchyma or embedded in the serosa. There was extensive connective tissue proliferation with mononuclear cell infiltration around the cyst. Leucocytozoon-specific DNA was detected in all the flocks by PCR. Phylogenetic analysis of the cytochrome b gene of L. caulleryi reported from various parts of the world revealed that L. caulleryi is grouped into two major clusters (Cluster I & II). Further, Indian L. caulleryi sequences fall under sub-cluster I and II along with L. caulleryi reported from Taiwan, Egypt, China, Myanmar, Japan, South Korea, and Thailand.

Serpentinised olivine used in tundish refractory working layer: A source of blowhole defect in steel billets

In this research, the effect of different types of commercial tundish refractory working layers (gunning mix, prefabricated board (PB), and dry mix) on the formation of blowhole defect in continuous casting steel billets was investigated. To protect the tundish body, three refractory layers are applied on its metallic shell including a safety layer, a permanent layer, and a working layer. Due to the direct contact of molten metal and slag with the tundish working layer, this layer plays an important role in guaranteeing the quality of steel. In the current research, the amount of molten metal hydrogen pick-up due to contact with the abovementioned tundish working layers was measured by a Hydris device. The hydrogen content of all the melts increased after transferring from ladle to tundish, but the rising rate strongly depended on the type of tundish working layer with PB having a minimum amount of hydrogen pick-up. To characterise the working layers, their chemical and mineralogical composition as well as their thermal behaviour up to 1400 °C were evaluated using X-ray fluorescence, X-ray diffraction, and thermogravimetry-differential scanning calorimetry techniques. The results showed that olivine is a main constituent of all the working layers. Also, the amount and quality of olivine (especially the amount of its serpentinization) have a great effect on the formation of blowhole defects in the steel billets.

Highly luminescent CsPbBr3 perovskite nanocrystal films via the ligand-assisted reaction

Via the ligand-assisted reaction, highly luminescent CsPbBr3 perovskite nanocrystal (PNC) films were synthesized by a simple centrifugal casting process based on the supersaturated recrystallization method. The structure, the optical properties, the morphology, the stability and the potential application of the PNC films were investigated in detail. The results show that under the joint use of OA, DDAB and APTES, the obtained PNC films with 1.5 M DDAB show the strong PL emission with highest quantum yield of 77.5 %, the pure CsPbBr3 structure, the smooth surface and the enhanced stability under UV irradiation. Additionally, the white LED device based on the PNC films obtained here and a commercial red phosphor layer shows excellent optical and color properties and working stability, demonstrating the potential of the PNC films in this study in the field of light-emitting and display.

Full micro-nanofiber aerogel with three-dimensional fluffy network structure for rapid liquid absorption and uniform liquid retention in diapers

Diapers are essential for infants and patients with urinary incontinence. The super-absorbent polymer (SAP) in the core layer of diapers suffers from slow liquid absorption, fault formation, and reverse osmosis. Therefore, it is desirable to construct a core layer that can integrate rapid liquid absorption, uniform retention, and anti-seepage qualities. In this study, a diaper core layer and a three-dimensional fluffy network structure with a wetting gradient was constructed via one-step solution blow spinning (SBS). By regulating the content of the glutaraldehyde (GA) cross-linking agent, absorbent and insoluble fibers could be obtained. The ratio of super-absorbent fibers (SAF) to PAN-PVP micro-/nano fibers in the three-layer fiber structure and the gram weight of the core layer were adjusted. A wetting gradient was established when the weight of the adjusted gradient core layer was 2/3 that of the commercial core layer. The amount of reverse osmosis was reduced by 0.25 g, and the liquid absorption and retention were 30 times and 28.5 times, respectively, two and 3.5 times higher than those of commercial diapers. The SAF prepared by SBS could improve the core layer's liquid absorption rate, retention ratio, and comfort. The fibers are applicable in diapers, sanitary napkins, and other disposable products.

A pilot survey on the identification of different deformities and prevalence of cracked eggs in commercial layers’ farms in Ogbomoso metropolis, Oyo State, Nigeria

This research was conducted within Ogbomoso town, Oyo State, to identify the different types of cracks and deformed eggs common in the study area. It highlighted the socio-economic characteristics of the commercial layer farmers, flock characteristics, feed and feeding, veterinary service, cracks and deformed eggs incidence, causes of deformed eggs, and measures to minimize them. Data were collected through a structured questionnaire administered on 40 identified commercial layer farms that were randomly selected. Data analyses were carried out using frequency counts, pie charts, and percentages. The result of the study indicated that the majority (90%) of the respondents were male with a few (10%) females, and the majority (90%) were Christian with 10% Muslims. The entire respondents attained tertiary education. Seventy-five percent (75%) of the studied farm used veterinary services on their farm and 25% did not. All (100%) of the farms studied experience one type of cracks/deformed eggs or the other. The most common cracks and deformed eggs observed in this research were gross cracks (15.52%), blood spots (13.79), and thin shells (12.93%) while mottled crack (0.86%) was the least experienced crack. The causes of cracks and deformed eggs as indicated by the farmers showed that cracks and deformed eggs were majorly caused by birds’ cages (23.2%), birds (20.3%), and vermin (15.9%), and few were caused by diseases, hormonal changes and during the process of eggs transportation. The major means of controlling cracks and deformed eggs observed in this research were proper handling of the eggs (22.7%), disease prevention (19.7%), and control of rats (19.7%) while the least control measure suggested was the use of antibiotics. Gross crack which resulted in a large hold and broken membrane is the most common egg crack in the farms. The results of this research show that all the farms studied experience cracks and deformed eggs on their farms and different approaches are being used to minimize the effect therefore, farmers need to minimize the occurrence in other to reduce the loss of money through it.

C2H2-type zinc-finger protein BCL11B suppresses avian Leukosis virus subgroup J replication by regulating apoptosis

Apoptosis plays a crucial role in host antiviral defense. The avian leukosis virus subgroup J (ALV-J), an avian oncogenic retrovirus, has been shown to suppress apoptosis while promoting its own replication. ALV-J induces myeloid tumors and hemangiomas in chickens resulting in significant economic losses for commercial layer and meat-type chicken production. B-cell lymphoma/leukemia 11B (Bcl11b) encodes a C2H2-type zinc finger protein—BCL11B, that exerts critical functions in cell proliferation, differentiation, and plays an essential role in the immune system. Previous study has been shown that Bcl11b is associated with ALV-J infection. In this study, we further investigated the pathological changes in ALV-J infected cells and examined the role and expression regulation of chicken Bcl11b. Our results demonstrate that Bcl11b, as an interferon-stimulated gene (ISG), encodes C2H2-type zinc finger protein BCL11B that promotes apoptosis to inhibit ALV-J infection. Additionally, gga-miR-1612 and gga-miR-6701-3p regulate apoptosis and are involved in ALV-J infection by targeting Bcl11b, thus revealing immune response strategies between the host and ALV-J. Although the underlying mechanisms require further validation, Bcl11b and its regulatory miRNAs are the first to demonstrate inhibition of ALV-J replication via apoptosis. BCL11B can a valuable target for treating diseases triggered by ALV-J infection.

Comparing performance, morphological, physical, and chemical properties of eggs produced by 1940 Leghorn or a commercial 2016 Leghorn fed representative diets from 1940 to 2016

Eggshell quality is one of the most significant factors affecting the egg industry as it economically influences the quantity of saleable eggs. Eggshell quality can be improved through optimization of genotype, housing system, and mineral nutrition. This study aimed to compare genotypes and evaluate the morphological, physical, and chemical properties of eggs (weight, breaking strength, Haugh units, and dry matter) by hens of two different strains fed a 1940 and 2016 representative diet. Egg production was measured daily and there were four periods with 10-wk intervals in which eggs were analyzed starting at 30 wk and ending at 60 wk of age measuring quality parameters. This study was set as a 2 × 2 factorial. The factors consisted of 2 leghorn genetic strains that were a 2016 commercial layer (W36) and a 1940 random-bred leghorn line, then 2 diets based on 2016 and 1940 dietary standards. The treatment groups: 1) 2016 hen on 1940 diet, 2) 2016 hen on 2016 diet, 3) 1940 hen on 1940 diet, and 4) 1940 hen on 2016 diet had 8 replicates with 10 hens per treatment housing 2 hens per cage. Body weights were higher in the 2016 hens when compared to the 1940 hens, however, the feed conversion ratio fluctuated in hens with the 2016 hens on the 1940 diet consuming the most feed throughout the majority of the trial. The 1940s hens came into production later than the 2016 hens; however, the rate of production was consistent with one another. Oviduct and ovary weights were heavier in the 2016 hens when compared to the 1940 hens. Egg quality, both interior and exterior was greater in the 2016 hens when compared to the 1940 hens. Parameters measured demonstrated significant differences (P ≤ 0.05) among treatment groups suggesting that genetics and nutrition both played a role in production rate and egg quality.