Search Results (37)

Bacteria such as Salmonella spp. are primarily transmitted through contaminated eggs and infected poultry; however, other routes, including the movement of personnel, vehicles, and lapses in biosecurity protocols, also play a significant role in their dissemination within poultry systems. Control of a wide range of microorganisms, including bacteria, is often carried out using chemical agents, such as formaldehyde, applied in its solid, liquid, or gaseous forms. Reports on the use of formaldehyde in poultry production date back more than a century. However, it continues to attract research interest due to growing concerns about bacterial resistance, embryotoxicity, occupational exposure, the generation of toxic byproducts, and the search for safer alternatives in poultry production systems. It remains widely used worldwide, but comprehensive and updated evaluations of its efficacy, toxicity, and risks to both poultry and workers are still limited. This review aims to synthesize the current knowledge on the use of formaldehyde in poultry production. Overall, the synthesis shows that formaldehyde remains an effective but high-risk sanitizer whose continued use in poultry systems requires rigorous control and monitoring protocols, and that the development and adoption of efficient and safer alternatives is recommended. Full article

This study assessed the microbiological quality of free-range eggs produced in Southeastern Brazil, focusing on the effects of collection location. Eggs were collected from either nest boxes (designated laying areas containing clean substrate) or from the bedding substrate (litter-covered floor of the poultry house). Eggs from the bedding had significantly higher counts of thermotolerant coliforms, psychrotrophs, and Staphylococcus compared to nest-collected eggs. Across all evaluated microorganisms, eggshells showed greater contamination than the internal contents. Bedding substrates showed higher counts of mesophilic aerobes, psychrotrophs, Staphylococcus, and Clostridium compared to nest box substrates. Eggs from the bedding showed compromised internal microbiological quality, with coliform values exceeding 2 log10 most probable number (MPN) per mL. Further, 10% of the evaluated pools were suggestive of the presence of Salmonella spp., in the internal components of bedding eggs and on the shells of nest eggs. Therefore, it is strongly recommended that eggs be collected from nest boxes right after laying, while eggs laid on the bedding substrate should be excluded from human consumption. Full article

Eggs are good sources of animal proteins. Methods for creating designer eggs are attractive to scientists and producers of the eggs, in order to fulfill customers’ demands. We review and summarize the current understanding of how genetic and environmental factors influence chicken egg components, specifically, amino acid contents of yolk and albumen. Genetically diverse breeds of chicken enable us to obtain a wide variety of egg amino acids. Moreover, the use of fermented feed and different rearing systems (barn and deep litter) has impacts on egg amino acids, which may be mediated through changes in the intestinal environment, including the microbiota. To overcome the future food crisis, the combinations of breeds, feeds, and rearing systems will be important for producing designer eggs. In the future, not only long-term selected layer strains will be required, but also many kinds of indigenous chicken breeds, which have already adapted to each local environment in the world, should be investigated under the continental levels of climate environment using different fermented feed materials. To better understand the interplay between genetic and environmental factors, we will offer valuable insights for both egg producers and consumers, potentially guiding future efforts to optimize egg amino acid contents in chickens. Full article

This study evaluated the effects of Bacillus toyonensis BCT-7112^T on laying duck performance, egg quality, ammonia emission, and cecal microbiota. Two hundred twenty 32-week-old Khaki Campbell ducks were assigned to four dietary treatments (0, 200, 500, or 1000 ppm Toyocerin^® 10⁹ premixture, containing 1 × 10⁹ B. toyonensis BCT-7112^T CFU/g) with five replicate pens of eleven birds each. Data on productivity, egg quality, and ammonia emissions were collected weekly, and cecal microbiota were analyzed at 44 weeks of age. Supplementation with 1000 ppm B. toyonensis BCT-7112^T significantly increased average egg weight (p < 0.001) and eggshell thickness (p = 0.007). Egg mass also improved at higher supplementation levels (p < 0.05), though feed intake, feed conversion, daily egg production, and most egg quality parameters were unaffected (p > 0.05). Ammonia emissions in litter decreased significantly (p < 0.05) with probiotic inclusion. Cecal microbiota analysis revealed higher diversity in ducks fed 1000 ppm, with a notable shift in predominant phyla from Bacteroidetes (35.12%) and Firmicutes (34.93%) in the controls to Bacteroidetes (40.52%), Firmicutes (34.08%), and Deferribacteres (9.54%) in the treated ducks. The findings suggest that 1000 ppm B. toyonensis BCT-7112^T enhances egg production, eggshell quality, and microbial diversity while reducing ammonia emissions in laying duck systems. Full article

Fungi are a typical part of the microbiome of poultry houses, but some of the genera can be pathogenic for poultry and humans. An investigation was conducted on 200 duck eggs from 10 flocks to determine total fungal contamination on the eggshells. The colony types were identified morphologically and microscopically, and a representative group was identified using PCR. The resistance profiles for all obtained Aspergillus isolates were conducted. The dominating genera on eggshells were Penicillium, Alternaria and Aspergillus and the number of fungal colonies ranged from 0 to 7100. Aspergillus fumigatus was cultured from 9.5% eggshells, and all isolates were obtained from three flocks. The minimum inhibitory concentration (MIC) values for A. fumigatus isolates ranged from 0.094–32 μg/mL for amphotericin B (MIC 50 1 mg/L and MIC 90 32 μg/mL), 0.125–32 μg/mL for caspofungin (MIC 50 0.38 μg/mL and MIC 90 32 μg/mL), 0.19–32 μg/mL for itraconazole (MIC 50 1.5 μg/mL and MIC 90 32 μg/mL), 0.047–12 μg/mL for posaconazole (MIC 50 0.5 μg/mL and MIC 90 8 μg/mL) and 0.023–32 μg/mL for voriconazole (MIC 50 0.19 μg/mL and MIC 90 32 μg/mL). A total of 73.7% of the isolates were resistant to posaconazole and 68.4% to itraconazole. Nearly half of the strains (47.4%) showed resistance to amphotericin B and 31.6% to voriconazole. Because of the lack of antifungals registered for poultry, hygiene and the regular disinfection of litter in particular are needed to prevent the contamination of the eggs by fungi for both animal and human health. Full article

Reproduction in goats is a highly complex and dynamic process of life regulation, involving coordinated regulation from various aspects such as central nervous system regulation, reproductive system development, oocyte maturation, and fertilized egg development. In recent years, researchers have identified numerous genes associated with goat reproductive performance through high-throughput sequencing, single-cell sequencing, gene knockout, and other techniques. However, there is still an urgent need to explore marker genes related to goat reproductive performance. In this study, a single-cell RNA sequencing dataset of oocytes (GSE136005) was obtained from the Gene Expression Omnibus (GEO) database. Weighted Gene Co-expression Network Analysis (WGCNA) was utilized to identify modules highly correlated with goat litter size. Through gene function enrichment analysis, it was found that genes within the modules were mainly enriched in adhesive junctions, cell cycle, and other signaling pathways. Additionally, the top 30 hub genes with the highest connectivity in WGCNA were identified. Subsequently, using Protein–Protein Interaction (PPI) network analysis, the top 30 genes with the highest connectivity within the modules were identified. The intersection of hub genes, key genes in the PPI network, and differentially expressed genes (DEGs) led to the identification of the RPL4 gene as a key marker gene associated with reproductive capacity in goat oocytes. Overall, our study reveals that the RPL4 gene in oocytes holds promise as a biological marker for assessing goat litter size, deepening our understanding of the regulatory mechanisms underlying goat reproductive performance. Full article

Reproductive traits hold considerable economic importance in pig breeding and production. However, candidate genes underpinning the reproductive traits are still poorly identified. In the present study, we executed a genome-wide association study (GWAS) and runs of homozygosity (ROH) analysis using the PorcineSNP50 BeadChip array for 585 Yorkshire pigs. Results from the GWAS identified two genome-wide significant and eighteen suggestive significant single nucleotide polymorphisms (SNPs) associated with seven reproductive traits. Furthermore, we identified candidate genes, including ELMO1, AOAH, INSIG2, NUP205, LYPLAL1, RPL34, LIPH, RNF7, GRK7, ETV5, FYN, and SLC30A5, which were chosen due to adjoining significant SNPs and their functions in immunity, fertilization, embryonic development, and sperm quality. Several genes were found in ROH islands associated with spermatozoa, development of the fetus, mature eggs, and litter size, including INSL6, TAF4B, E2F7, RTL1, CDKN1C, and GDF9. This study will provide insight into the genetic basis for pig reproductive traits, facilitating reproduction improvement using the marker-based selection methods. Full article

Research in recent years has shown that some species of predatory mites, considered to be typically associated with soil and litter, can also be found on plants. Such species include Blattisocius mali, which is an effective predator of acarid mites, nematodes and the eggs of moths and which can disperse by means of drosophilid fruit flies. Apart from soil and litter or storage, it has also been recorded on the bark of apple trees and the leaves of strawberries, thus suggesting its possible predation of/feeding on herbivorous mites and insects. Our goal was to examine whether B. mali could consume different development stages of two polyphagous herbivores, the two-spotted spider mite, Tetranychus urticae, and the western flower thrips, Frankliniella occidentalis, as well as the drosophilid fruit fly Drosophila hydei. In 24 h cage tests, single, starved B. mali females consumed all types of prey offered, i.e., the eggs, males and females of spider mites; the first-instar larvae and prepupae of thrips; and the eggs and first-instar larvae of fruit flies. The potential for B. mali to prey upon these insects and mites was confirmed. However, to estimate whether it can also effectively reduce their population, additional tests on the predator’s survival, fecundity and prey preference are needed. Full article

Regression models are extensively used to explore the relationship between a dependent variable and its covariates. These models work well when the dependent variable is categorical and the data are supposedly independent, as is the case with generalized linear models (GLMs). However, trait data from related species do not operate under these conditions due to their shared common ancestry, leading to dependence that can be illustrated through a phylogenetic tree. In response to the analytical challenges of count-dependent variables in phylogenetically related species, we have developed a novel phylogenetic negative binomial regression model that allows for overdispersion, a limitation present in the phylogenetic Poisson regression model in the literature. This model overcomes limitations of conventional GLMs, which overlook the inherent dependence arising from shared lineage. Instead, our proposed model acknowledges this factor and uses the generalized estimating equation (GEE) framework for precise parameter estimation. The effectiveness of the proposed model was corroborated by a rigorous simulation study, which, despite the need for careful convergence monitoring, demonstrated its reasonable efficacy. The empirical application of the model to lizard egg-laying count and mammalian litter size data further highlighted its practical relevance. In particular, our results identified negative correlations between increases in egg mass, litter size, ovulation rate, and gestation length with respective yearly counts, while a positive correlation was observed with species lifespan. This study underscores the importance of our proposed model in providing nuanced and accurate analyses of count-dependent variables in related species, highlighting the often overlooked impact of shared ancestry. The model represents a critical advance in research methodologies, opening new avenues for interpretation of related species data in the field. Full article

The aim of the study was to evaluate the effect of genotype on the productivity and egg quality of three hen strains included in the genetic resource protection program in Poland. The study encompassed populations of laying hens, i.e., Rhode Island Red/RIR (R-11 and K-22) and Rhode Island White (A-33). The analysis over five generations included the basic production traits, i.e., the weight of the birds at 20 weeks (g), egg weights at 33 and 53 weeks, sexual maturity, the number of eggs laid up to 56 weeks of age, and hatchability parameters. In addition, the effective population size (N_e) and flock homozygosity coefficient (F_x) were calculated for each breed. Population health during the rearing and production periods was also recorded. The study also determined egg content and shell quality traits in relation to the age of the hens. The birds were kept on litter at a stocking rate of 5 hens/m² and fed ad libitum with a standard feed mixture for hens. Based on the results, it was concluded that the evaluated hen populations (R-11, K-22, and A-33) are valuable strains, representing a reservoir of unique phenotypic and egg quality traits. It was shown that the random mating system used in the reproduction of flocks effectively protects the populations from an increase in the degree of inbreeding. An influence of hens’ origin (genotype) and age on the performance results, as well as egg quality traits, was found. Over five generations, the evaluated hen strains were characterized by high survival rates (above 98%). The study also found a large variation between the R-11 and K-22 strains and the A-33 strain in terms of the evaluated performance traits, especially in the body and egg weights, sexual maturity age, and laying performance of hens. The earliest to start laying were hens from the K-22 strains, which also showed significantly (p ≤ 0.05) higher laying performances compared to R-11 hens. The results also indicate that the quality of eggs from hens of the compared strains varied. This was particularly true for such traits as shell color; egg, shell, and yolk weight; and shell quality. It was also shown that many egg and shell quality traits change with the age of the hens. The analysis of the obtained data indicates that the adopted methods of conservative breeding for these populations have influenced the success of the conservation program. Full article

The welfare of laying hens in conventional caged houses has become an increased public concern, leading primary food chains, restaurants, and grocers in the United States to pledge to source only cage-free (CF) eggs by 2025 or 2030. Cage-free housing systems have been considered as a more humane alternative; however, they still come with certain challenges. One of the primary challenges with CF housing is the poor indoor air quality due to the high levels of ammonia (NH₃) and particulate matter (PM). Despite the importance of air quality in animal welfare, most studies have focused on the egg-laying stage, thereby leaving a significant knowledge gap in the pullet phase. Addressing this gap is essential to ensure the well-being of laying hens in CF housing and to help producers and researchers identify effective strategies to mitigate the impact of poor indoor air quality on the bird’s health and welfare. Therefore, the objective of this study was to (a) examine the effect of the pullets’ age on NH₃ and PM levels, and (b) find the effect of housing, litter moisture content (LMC), and relative humidity (RH) on air pollutant concentrations. The results show that the PM levels of PM_2.5, PM₁₀, and total suspended particles (TSP) increased significantly with the growth of birds from 1 to 16 weeks of age (WOA) (p < 0.01). For instance, PM_2.5, PM₁₀, and TSP levels were measured at 0.023 ± 0.003, 0.031 ± 0.004, and 0.058 ± 0.013 mg m⁻³ in the first week, and these levels increased to 1.44 ± 0.58, 2.723 ± 1.094, and 6.39 ± 2.96 mg m⁻³, respectively, by 16 WOA. In addition, PM levels measured near the perch were found to be three times higher than other locations inside the rooms (e.g., between the feeder and drinker or near the exhaust fan) (p < 0.01), as perching is one of the primary reasons for dust generation. Furthermore, a significant interaction between the age of the pullets and PM levels was found (p < 0.01), as the litter quality and the behaviors of birds were changing over time. For NH₃ levels, average daily concentrations were lower than 1 ppm at 16 WOA for all rooms due to dry litter conditions (i.e., 9–10% LMC). Additionally, RH has been shown to have a significant effect on air pollutant concentration. Overall, the results indicate that the bird’s age significantly affects PM generation and PM variation within the rooms. The variation of PM was directly affected by RH inside the house. Therefore, this research will provide valuable information for both researchers and producers to control air pollutant emissions from the pullet stage in CF housing to ultimately improve the health and welfare of hens. Full article

Many countries have gradually shifted to animal welfare-friendly housing systems for egg layers. However, there is still no consensus among researchers on whether the housing system affects egg quality traits. Therefore, this study aimed to determine the effects of housing systems on egg traits and free amino acid contents of albumen and yolk using two types of housing systems, the conventional cage (cage) system and a floor rearing (litter) system. Tosa-jidori (n = 20) hens were divided into two groups. Experiments during the 7 weeks were performed twice by switching the housing systems (first and second stages). One-way analysis of variance was used to evaluate the effects of housing systems on body weight gain, egg traits, albumen and yolk amino acid contents, and fecal corticosterone. We observed significant housing effects in body weight gain, eggshell weight, yolk weight, eggshell thickness, eggshell lightness, and several albumen amino acids (A_Gln, A_His, A_Met, A_Cys, A_Lys, A_Asp, A_Glu, A_Ser, A_Thr, A_Ala, A_Pro, and A_Phe). Notably, a robust effect was seen in eggshell lightness, even after switching housing systems. These results suggest that eggshell lightness and several egg traits, including albumen amino acid contents, can be changed by using the different housing systems. Full article

The extent of the feathers covering a bird’s body and the condition of the plumage largely determine the bird’s well-being and aesthetic condition. This investigation aimed to compare changes in the plumage status of laying hens in dissimilar housing systems in the egg-laying period. The experiment was carried out with 1460 non-beak-trimmed laying hens, provided by Bábolna TETRA Ltd., representing a part of the Rhode-type elite lines (Rhode Island Red (RIR) and Rhode Island White (RIW)) used for breeding brown layer hybrids. Hens were kept in the closed experimental laying house of MATE University (Kaposvár Campus), where the RIR and RIW hens were placed into three types of housing systems: EU standard furnished cage (EU) (7560 cm²; 10 hens/cage; 756 cm²/hen); Alternative pen (A) (5.52 m², floor and litter combination, 53 hens/pen; 1040 cm²/hen); and Conventional cage (C) (3780 cm²; 6 hens/cage; 630 cm²/hen). The feathering status of the hens was examined at five body parts: neck, breast, wings, back and tail at 33, 45 and 61 weeks of age, which was evaluated on a four-grade scale by the same experienced scorer, and the cumulated plumage point (5–20) was calculated for each hen. The RIW genotype had a better plumage condition than RIR at each of the examined times (at the 33rd week: 19.0, 18.3; at the 45th week: 18.4, 17.4; at the 61st week: 17.2, 15.5). The status of the plumage of the RIR hens had deteriorated to a greater extent. As age progressed, the plumage condition of both genotypes significantly deteriorated in all the three housing technologies. The relatively high level of deterioration can be partly explained by the fact that the animals were non-beak-trimmed. At all test times, the total feather score of the birds in the alternative cage housing was significantly better (at the 33rd week: EU: 18.4, A: 19.1, C: 18.5; at the 45th week: EU: 17.6, A: 18.6, C: 17.4; at the 61st week: EU: 15.9, A: 16.9; C: 16.1). The condition of the neck plumage was better in group RIW than in RIR, and the best in the alternative housing at each test time. At the end, the high decomposition results were striking, since at the beginning there were values close to the maximum (3.98; 3.99). It can be concluded that the reason for the dominantly favorable aviary results is that the hens in this type of housing have to come into contact with fewer mechanical factors, their companions do not jump on their backs when changing places, they do not have to stick their heads out of the grid to collect feed, etc. In addition to all this, they also had a littered scratching area and a nest lined with artificial grass, where they could scratch and take a dust bath. Full article

The poultry industry has met more than one-third of the human demand for meat and all the demand for eggs during the past several decades, and it has also been recognized as a very efficient sector in the livestock industry. However, increasing poultry production has also led to the massive generation of various poultry wastes, which are a great threat to climate change, environmental safety, and human health. Traditionally, landfilling and burning are the most frequently used techniques for treating poultry waste. With rich contents of organic matter, nutrients, and keratin, poultry waste can be applied to produce value-added products that can be used in many sectors by using a variety of emerging technological processes. Considering the massive generation, profound environmental pollution, and wide range of applications of poultry waste, this paper categorizes poultry waste as litter and manure waste, feather waste, mortality waste, abattoir waste, and hatchery waste. This paper also reviews modeling and simulation studies on poultry waste-to-wealth, and six current or emerging technological processes for poultry waste-to-wealth are described: anaerobic digestion, pyrolysis, gasification, hydrolysis, enzymatic treatment, and microbial conversion. Finally, the economic, environmental, and social impacts of the sector of poultry waste-to-wealth are discussed. For further research, we suggest a focus on the poultry waste-to-wealth projects in different regions, the behavior strategy of different stakeholders, and policymaking for the commercialized application of poultry waste-to-wealth technologies. Full article

Poultry farming involves the production of poultry manures (PMs), which, if properly managed, are excellent organic soil amendments. Poultry farms generally do not have adequate arable land, and therefore, valuable fertilizer becomes a problematic waste. During the production and storage of PMs, odorous VOCs, NH₄, H₂S, and potent greenhouse gases such as CH₄, CO₂ are emitted. It influences the productivity of poultry and negatively affects the working conditions of working staff. In the present study, mineral–microbial deodorizing preparations (MMDP) based on perlite and bentonite as well as the following microorganism strains Lactobacillus plantarum, Leuconostoc mesenteroides, Bacillus megaterium, B. subtilis, and Pseudomonas fluorescens were added to the litter of turkey broilers (TB) and egg-laying hens (LH). PMs were compared with treatments without the addition of MMDP, and maize, sunflower, and rapeseed forage crops were tested. The influence on soil parameters such as pH, EC, HAC, SBC, CEC, BS, N_tot, C_tot, and plant yield and parameter of photosynthesis, i.e., SPAD index, was tested. Soil amending with manure resulted in an increase in pH and a decrease in HAC; in addition, an increase in EC, which was counteracted by the addition of MMDP, was noted. MMDP positively affected parameters such as SBC, CEC, and BS. It was shown that PMs, with the addition of MMDP, improved crops’ yield in the first year of the study, whereas this effect was not seen for the after-crop plants (lupine). The main ‘added value’ related to the usage of MMDP in poultry production is the improvement in the properties of PMs, which mainly had a positive effect on soil indicators. Full article