Search Results (27)

Since the early 2000s, the poultry industry in our nation has steadily progressed towards a larger scale and increased intensification. However, the growing demand for animal-based protein, combined with significant increases in feed ingredient costs, presents substantial challenges to the advancement of egg production. The regulation of feed utilization efficiency in laying hens is a complex process, influenced by various factors including the farming environment, feed composition, microbial ecosystems, and hormonal dynamics. The feed conversion rate in laying hens not only serves as a critical indicator of agricultural productivity but also highlights the significant impact of molecular technologies in improving feed efficiency. These technological advancements have enhanced the precision and effectiveness of breeding practices while providing substantial support for optimizing feed management, improving production metrics, and promoting sustainable agricultural practices. This comprehensive synthesis of factors, regulatory pathways, and cutting-edge molecular methodologies establishes a biological framework for future breeding strategies. Notably, this review uniquely emphasizes the pivotal role of modern molecular biology techniques—such as genomic selection, transcriptomic profiling, and gene-editing tools—in decoding feed conversion efficiency (FCE), contributing to broader goals of agricultural sustainability by balancing productivity gains with eco-friendly and cost-effective egg production. Full article

Feather pecking (FP) is a significant welfare and economic problem in laying hen husbandry. While there is growing evidence that the glutamatergic system plays a crucial role in regulating FP behavior, the biological mechanisms remain unclear, largely due to the limited uptake of peripheral glutamate across the blood–brain barrier (BBB). Here, we applied a multi-omics approach combined with physiology assays to answer this question from the perspective of the gut–brain axis. A total of 108 hens were randomly assigned to two groups (treatment and control) with six replicates each, and the treatment group was subjected to chronic environmental stressors including re-housing, noise, and transport. We found that chronic exposure to environmental stressors induced severe FP, accompanied by reduced production performance and increased anxiety- and depression-related behaviors, compared to controls. In addition, the immune system was potentially disrupted in FP chickens. Notably, gut microbiota diversity and composition were significantly altered, leading to decreased microbial community stability. Non-targeted metabolomic analysis identified a variety of differential metabolites, primarily associated with arginine and histidine biosynthesis. A significant increase in glutamate levels was also observed in the hippocampus of FP chickens. Transcriptome analysis revealed the upregulated expressions of glutamate-related receptors GRIN2A and SLC17A6 in the hippocampus. Correlation analysis indicated that GRIN2A and SLC17A6 are positively associated with arginine levels in the duodenum, while Romboutsia in the duodenum is negatively correlated with arginine. These findings suggest that intestinal bacteria, including Romboutsia, may influence FP behavior by altering plasma arginine and histidine levels. These changes, in turn, affect glutamate levels and receptor gene expression in the hippocampus, thereby regulating the glutamatergic system. Our research offers insights into novel strategies for mitigating harmful behaviors in poultry farming, with potential benefits for animal performance and welfare. Full article

The modern livestock industry faces significant challenges due to the extension of production cycles and a growing shortage of feed resources. Low-protein (LP) diets offer potential environmental advantages whereas damage intestinal integrity and increase pro-inflammatory cytokines. Bile acids (BAs), metabolic products of cholesterol in the liver, possess strong antioxidative and immune properties. This study evaluated the effects of dietary porcine BA supplementation at different protein levels on the antioxidant status, immune function, and gut microbiota of late-laying hens. A 2 × 2 factorial design was employed with 198 Hy-Line Brown laying hens (62 weeks old), randomly divided into one of four treatment groups with 8 replicates for each treatment. Diets included normal (16.42%) or low-protein (15.35%) levels, with porcine BAs supplemented at 0 or 120 mg/kg (62–69 weeks) and 0 or 200 mg/kg (70–75 weeks) over 14 weeks. Dietary protein levels and bile acids had no effect on organ development in laying hens. Low-protein diets increased serum anti-inflammatory cytokines IL-4 and IL-10 but elevated pro-inflammatory cytokines IL-1β (p < 0.05), corroborated by higher IL-10 gene expression in the ileum mucosa (p < 0.05). The supplementation of bile acids improved immune function by increasing serum IL-4 and TGF-β while decreasing IL-6 levels (p < 0.05). Moreover, bile acids treatments upregulated IL-10, TGF-β and ZO-1 gene expression in the ileum mucosa (p < 0.05) and alleviated oxidative stress by enhancing serum GSH-Px activity (p < 0.05). Additionally, both low-protein diets and bile acids enriched beneficial cecal bacteria, including Hungatella and Blautia, primarily linked to immune function. These findings demonstrate that porcine bile acids administration improve antioxidant capacity, immune function and gut microbiota dysbiosis. These beneficial effects were associated with Hungatella and Blautia levels, which may be responsible for the porcine bile acids efficacy in poultry nutrition. Full article

The growing demand for sustainable and healthier egg production systems, combined with the need to reduce the use of synthetic additives in poultry feed, has led to an increased interest in natural feed supplements. This study evaluated the effects of dietary supplementation with ecological sea buckthorn (Hippophae rhamnoides) powder on the performance and egg quality of 600 laying hens of the Moravia Black breed, raised in a free-range system. Three groups were included: one control group with standard feed and two experimental groups supplemented with 1% and 2% sea buckthorn powder. Over 11 weeks, parameters such as egg production, feed consumption, and egg quality, including egg weight, volume, shell thickness, and yolk color, were monitored. The 2% supplementation significantly improved egg production, egg weight, shell strength, and yolk carotenoid content, with stable feed consumption and negligible mortality, confirming the additive’s safety. These results highlight the potential of sea buckthorn powder as a natural feed additive to enhance poultry productivity and product quality, supporting sustainable and healthier egg production. Full article

The large-scale insect rearing sector is expected to grow significantly in the next few years, with Hermetia illucens L. (black soldier fly, BSF) playing a pivotal role. As with traditional livestock, it is essential to improve and ensure BSF welfare. A starting point can be an adaptation of the Five Freedoms framework. Feed availability must be optimized to meet larvae nutritional needs (freedom from hunger) while maximizing substrate conversion efficiency. Similarly, rearing density needs to be optimized to ensure well-being, particularly in large-scale operations. In this study, Control (commercial laying hen feed) and Omnivorous substrates (vegetable and meat) were used as dietary regimes. In the first trial, three feeding rates were tested: 50, 100, and 200 mg feed/larva/day; in the second trial, three rearing densities were evaluated: 5, 10, and 15 larvae/cm². Performance parameters, including final larval weight, final frass biomass, growth rate, substrate reduction, feed conversion ratio, larval length, survival rate, larvae chemical composition, and process optimization, were studied. Our results show that a feeding rate of approximately 90 mg feed/larva/day in the Omnivorous diet and 175 mg feed/larva/day in the Control diet, along with a rearing density of 5 and 7.57 larvae/cm², respectively, in the Omnivorous and Control diets, produced optimal growth performances ensuring larval well-being. This outcome offers valuable insights for implementing good welfare practices in the insect farming sector and optimizing rearing management and efficiency. Full article

Alanyl-glutamine (Aln-Gln), a highly soluble and stable Glutamine-dipeptide, is known to improve the performance of poultry birds. This study aimed to investigate the effect of Aln-Gln during the rearing period on growth performance, nutrient digestibility, digestive enzyme activity, immunity, antioxidant status and relative gene expression of Hy-Line brown hens. A total of 480 healthy day-old Hy-line brown chicks with similar body weights were randomly divided into four dietary groups (8 replicates/group and 15 birds/replicate). Groups A, B, C and D were fed diets containing 0%, 0.1%, 0.2% and 0.3% Aln-Gln, respectively, for 6 weeks. The body weight (BW) and average daily gain (ADG) were higher in hens fed test diets compared with the control (p < 0.05). The feed conversion ratio (FCR) was better in test groups as compared to the control group (p < 0.05). The ADFI showed no significant difference between the groups. Dietary treatments had no effect on dry matter (DM), organic matter (OM) and crude fiber (CF) digestibility. The Aln-Gln also improved gross energy (GE) and crude protein (CP) digestibility (p < 0.05). It has also increased IgG levels in groups C and D. IgM levels were similar to the control in B, C and D. The Aln-Gln increased IL-1 in B and C, IL-2 in C and D, and IL-6 in all test groups (p < 0.05). The supplementation of Aln-Gln had no effect on serum antioxidant indices like CAT, MDA, GSH-PX, GSH, and SOD in 42-day-old growing hens. Aln-Gln supplementation had no significant effect (p > 0.05) on the activity of amylase and lipase, however, a significant improvement (p < 0.05) in the activities of trypsin and chymotrypsin was observed in the test groups. Supplemented Aln-Gln levels in the birds’ diets led to an increase in the expression of genes related to growth factors (IGF-1, IGFBP-5), immune markers (IL-1, IL-2, IL-6) and antioxidant status (GSH-Px1), as compared to control group. Aln-Gln supplementation in Hy-Line brown hens during their growing period improved growth, nutrient digestibility, immunity and digestive enzymes activity. These findings suggest that Aln-Gln is a promising dietary additive for enhancing poultry performance. Full article

Identifying alternative feedstuffs to replace conventional nutrient sources in poultry diets is crucial to supplying the growing demand for animal feed. A 17-week-long feeding experiment with three diets, including 0% (control), 10%, and 18% full-fat dried black soldier fly larvae (DBSFL), was conducted to evaluate the production efficiency and feed safety of using the larvae for partial (50%) and full (100%) substitutions of soybean meal and 90% replacement of soybean oil in free-range laying hen diets. Thirty hens (18–36 weeks old) were housed in two mobile poultry trailers per treatment level. The weight gain of hens, their feed intake, egg production, egg weights, feed conversion ratios, bird welfare parameters, hematology and blood metabolites, fecal microbiology, and digestive tract weights were examined. Control hens had higher weight gains, laid more and bigger eggs while consuming less feed, and had lower feed conversion ratios than 18% DBSFL hens. However, the production performances of 10% DBSFL hens were not significantly different from the control in many of the parameters considered (e.g., hen-day egg production or HDEP). In conclusion, partial replacement of soybean meal and oil with DBSFL in layer diets maintains production efficiency, feed safety, and hen health and welfare status. Full article

Farm animal welfare research conducted in China is not commonly accessed or known outside of China, which may lead to the assumption that farm animal welfare receives relatively little attention in China. Therefore, a bibliometric analysis was conducted on the existing Chinese farm animal welfare literature to provide robust evidence to refute this assumption. A total of 1312 peer-reviewed Chinese studies on farm animal welfare published between March 1992 and June 2023 were retrieved from the Web of Science (WoS) and the China National Knowledge Infrastructure (CNKI) database. CiteSpace software was used to analyze and visualize the number, species, authors, institutions, journals, and keywords of the papers. In China, farm animal welfare research has gone through the processes of an early stage (1992–2001), rapid-growth stage (2002–2007), and mature stage (2008–present), and the scale of research continues to grow. Notably, swine and chickens have received priority attention in this area. A Matthew effect was observed for authors and institutions, with relatively little collaboration among authors and institutions. Most of the papers were published in a small number of journals, with an apparent agglomeration characteristic. The research hotspots, summarized as “feed and diet”, “environmental impacts and control”, “integrated rearing management”, “injury and disease”, “behavior and technologies for behavior monitoring”, “genetic analysis”, “welfare during transport and slaughter”, “welfare-friendly animal product consumption”, “attitudes toward farm animal welfare”, and “healthy breeding”. The keywords “computer vision”, “recognition”, “temperature”, “precision livestock farming”, “laying hen”, and “behavior”, represent the major research frontiers in the field, which could indicate potential areas of significant future research. The findings of the present bibliometric analysis confirm the fact that farm animal welfare is a field of interest in China. Farm animal welfare research in China tends to be pragmatic, with a strong emphasis on enhancing growth and production performance, as well as product quality, rather than solely concentrating on improving farm animal welfare. This paper provides insightful references that researchers can use to identify and understand the current status and future direction of the farm animal welfare field in China. Full article

The conservation of threatened local livestock genetic resources involves characterising them to implement conservation strategies. The Utrerana is a Mediterranean-type chicken breed, included in the Official Catalogue of Livestock Breeds of Spain and in the Domestic Animal Diversity Information System (DAD-IS) of the Food and Agriculture Organization (FAO), native to south Spain created in 1926 by a farmer from Utrera (Seville province). It was selected for laying performance and with four plumage varieties (White, Black, Black-barred and Partridge), reaching average yields of 180 eggs per hen per year. It was widely used in commercial farming in the second quarter of the 20th century, being subsequently displaced in the second half of the 20th century by the spreading of the improved foreign breeds and lines. The Utrerana breed was reared from then on for its aesthetic values and in backyard systems, being endangered with a vulnerable local risk status (1822 birds in 2022 with an increasing trend) and having worsened its laying performance as selection for productivity ceased. The breed has received little attention from the research community. Therefore, this work aims to review the literature on the origin, selection, genetic and productive characterisation and status of the populations of the breed, as well as the conservation strategies. The Utrerana chicken is a polymorphic breed showing high genetic diversity, sexual dimorphism and morpho-functional differences among varieties. Currently, Utrerana hens start laying at 6 months of age, and a hen lays 94–121 high quality eggs (59–64 g) per year, showing seasonality. It is a slow-growing breed with mature weights of 2.4–2.6 kg for roosters and 1.9–2.0 g for hens. The Utrerana chicken breed is rustic and adapted to alternative farming systems. This review has identified research gaps to be filled, such as characterising the carcass and meat quality of the Utrerana chicken, and evidences the need to make efforts to promote the breed and expand its populations. Full article

Previous attempts to increase the level of flaxseed in hens’ diet for the production of n-3 polyunsaturated fatty acids (n-3 PUFAs)-enriched eggs have been commonly associated with undesirable effects on production efficiency, lipid health indices, and oxidative stability of eggs, requiring adequate research attention. This study investigated the effects of feeding a moderate level of flaxseed (FS) and plant polyphenol extracts (PPEs) on fatty acid content, oxidative stability, and lipid health indices in eggs of slow-growing Sasso T451A laying hens. One hundred and five hens were assigned to five groups (seven replicates of three) and fed on FS (75 g flaxseed and no antioxidants), VE8 (75 g flaxseed and 800 mg vitamin E), TS8 (75 g flaxseed and 800 mg Thymus schimperi), DA8 (75 g flaxseed and 800 mg Dodonaea angustifolia), and CD8 (75 g flaxseed and 800 mg Curcuma domestica) extract per kg diets. The egg yolk content of eicosapentaenoic acid (EPA, C20:5 n-3) in the DA8, TS8, and CD8 diets and docosahexaenoic acid (DHA, C22:6 n-3) in TS8 and CD8 diets significantly (p < 0.05) increased compared with the FS diet. The FS diet significantly increased the malondialdehyde (MDA) content in egg yolks, whereas the TS8 diet decreased it by 67% (p < 0.05). Little difference was observed in yolk fatty acid content between cooked and raw eggs. Production of n-3 PUFA-enriched eggs with favorable lipid health indices was possible through inclusion of PPEs extracted from local plant species grown in Ethiopia and a moderate dose of flaxseed in the diet of laying hens. Full article

We determined the longitudinal persistence of ceftiofur-resistant Escherichia coli from a chicken breeding farm in China. A total of 150 samples were collected from 5 breeding periods in a flock of layer hens, and the prevalence of ceftiofur-resistant E. coli fluctuated across the 5 chicken breeding stages: eggs, 3.33%; growing period, 100%; early laying period, 36.7%; peak laying period, 66.7% and late laying period, 80%. The most prevalent ceftiofur resistance genes were bla_CTX-M-55, bla_CMY and bla_NDM, and ST101 was the most prevalent and persistent sequence type across the breeding periods. Our results indicated that this breeder flock was heavily contaminated by ST101 ceftiofur-resistant E. coli and that its presence should be intensively monitored on chicken farms. Full article

The chicken egg is one of the most globally-consumed animal protein sources with high-quality protein value. However, there is a growing concern about the association between excessive egg consumption and the increasing risk of cardiovascular disease incidence. Meanwhile, corn silk extract (CSE) is known to have hypo-lipidemic bioactive properties, as well as antioxidant and anti-inflammatory effects. Thus, the present study was designed to investigate the effect of feeding laying hens three different CSE levels on egg cholesterol content as well as egg production performance and oxidative stress marker levels. A total of 240, 40-week-old, Hy-Line Brown laying hens were divided into 4 symmetric groups (10 hens × 6 replicates). The control group was fed a basal diet while the other three groups were given the basal diet supplemented with 100 mg, 200 mg, or 400 mg CSE per kg feed, respectively. Egg production performance was monitored for eight successive weeks. Internal and external egg quality parameters were also measured. At the end of week 48 of age, blood samples were collected to determine the plasma lipid profile, stress markers, and liver function indicators. Data revealed that supplementation of 200 mg and 400 mg CSE to laying hen diets had a positive effect on egg production performance with a significant increase in egg numbers and egg weight as well as significantly improved feed efficiency. Egg quality parameters were significantly improved with CSE supplementation. Lipid peroxidation levels and inflammation marker concentrations significantly decreased for the experimental groups that were fed 200 mg and 400 mg CSE compared with the control group. Meanwhile, blood total cholesterol decreased significantly with CSE supplementation, along with an increase in high-density and a decrease in low-density lipoprotein cholesterol content. A high positive correlation was found between liver and egg cholesterol contents (r = 0.902, p < 0.0001) which was linearly decreased with the increasing level of CSE supplementation. Egg cholesterol content significantly decreased by 9 to 19% in the CSE-supplemented groups compared with the control group. The present study demonstrated that CSE at 100 mg/kg and up to 400 mg/kg diets can be safely used to improve laying hen egg production performance with a direct effect on lowering egg cholesterol content as well as improving the redox status. Full article

The aim of the present study was to investigate the ability of two Italian slow-growing poultry breeds (namely, Bionda Piemontese, BP, and Bianca di Saluzzo, BS) to cope with a stressful event, such as collective grouping, using a multifactorial approach. A total of 120 hens of BP and BS breeds were homogenously distributed, according to breed, in 12 pens (10 hens/pen; 6 pens/breed), from 18 to 49 weeks of age. At 50 weeks of age, hens were regrouped (Stressful Farm Practice, SFP), by removing separators, both in indoor and outdoor areas. At 49 weeks of age, 24 hens/breed were randomly selected for the evaluation of welfare (ethological and physiological) parameters, at different time points: T0: 1-week pre-SPF; T1: 1-week post-SFP; T2: 3-week post-SFP; T3: 5-week post-SFP. Egg production was recorded from 38 to 56 weeks of age. Grouping produced a social stress in both BS and BP-laying hens, which was expressed in terms of productive traits (reduction of oviposition), behavioral modification (worsening of plumage condition due to feather peaking and extension of the duration of the tonic immobility test) and physiological modification (increased heterophil/lymphocyte ratio and corticosterone metabolites in droppings). Both breeds reacted in a similar way; in fact, no differences were attributed to the breed. At the end of the observation period, the egg rate fully recovered, while the behavioral and physiological parameters partially recovered but failed to recover to those recorded prior to the stressful event. Full article

Studies on animal behavior and welfare have reported that improving the management practices of pullets can enhance their growth, as well as their physical and mental condition, thus benefiting the productivity of laying hens. There is growing confidence in the international community to abandon the conventional practices of “cage-rearing and beak-trimming” to improve the welfare of chickens. Therefore, in this review, we summarized some of the effective poultry management practices that have provided welfare benefits for pullets. The results are as follows: 1. Maintaining similar housing conditions at different periods alleviates fear and discomfort among pullets; 2. Pullets reared under cage-free systems have better physical conditions and temperaments than those reared in cage systems, and they are more suitable to be transferred to similar housing to lay eggs; 3. Improving flock uniformity in appearance and body size has reduced the risk of pecking and injury; 4. Maintaining an appropriate population (40–500 birds) has reduced flock aggressiveness; 5. A combination of 8–10 h of darkness and 5–30 lux of light-intensity exposure via natural or warm white LED light has achieved a welfare–performance balance in pullets. (This varies by age, strain, and activities.); 6. Dark brooders (mimicking mother hens) have alleviated fear and pecking behaviors in pullets; 7. The air quality of the chicken house has been effectively improved by optimizing feed formulation and ventilation, and by reducing fecal accumulation and fermentation; 8. Complex environments (with litter, perches, straw bales, slopes, platforms, outdoor access, etc.) have stimulated the activities of chickens and have produced good welfare effects. In conclusion, the application of comprehensive management strategies has improved the physical and mental health of pullets, which has, in turn, improved the quantity and quality of poultry products. Full article

Demand for eggs from laying hens is increasing as the world population continues to grow. The use of insects as animal feed is a strategic opportunity to find a new innovative, economic and sustainable source of protein. The aim of this study was to evaluate the Italian consumer inclination for eggs produced with the use of insect-fed hens. The investigation on consumers’ readiness to adopt eggs from insect-fed hens was carried out through an online survey conducted on 510 participants. Survey results outlined four different clusters on the basis of the willingness to buy/eat eggs fed with insects: “ready” (40.1%), “environmentalist” (24.3%), “cautious” (21.7%), and “reluctant” (13.9%). “Ready”, “environmentalist”, and “cautious” were quite favorable to the use of insects as feed stuffs and share drivers for product choice: cheap, organic, and with an explicit indication of use of insects. On the other hand, for the “reluctant”, the diet based on insects was the main negative factor influencing product acceptance. This cluster also showed the highest level of neophobia. Italian consumers showed a considerable level of readiness to accept insects as feed material for egg production, which should be reinforced with further information on the origin and the environmental benefit of using insects. Full article