Search Results (872)

The deterioration of uterine calcium transport capacity induced by aging is a common problem for late-laying period hens, causing decline in eggshell quality. This study aimed to investigate the effects and possible regulatory mechanisms of dietary puerarin (PU) on calcium transport and eggshell quality in aged hens. Two hundred eighty-eight Hubbard Efficiency Plus broiler breeder hens (50-week-old) were randomly allocated to three dietary treatments containing 0, 40, or 200 mg/kg puerarin (PU), with 8 replicates of 12 birds each, for an 8-week trial. The results demonstrated that dietary PU ameliorated the eggshell thickness and strength, which in turn reduced the broken egg rate (p < 0.05). Histological analysis showed that PU improved uterus morphology and increased epithelium height in the uterus (p < 0.05). Antioxidative capacity was significantly improved via upregulation of Nrf2, HO-1, and GPX1 mRNA expression in the uterus (p < 0.05), along with enhanced total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-PX) activity, and decreased levels of the oxidative stress marker malondialdehyde (MDA) (p < 0.05). Meanwhile, PU treatment reduced the apoptotic index of the uterus, followed by a significant decrease in expression of pro-apoptotic genes Caspase3 and BAX and the rate of BAX/BCL-2. Additionally, calcium content in serum and uterus, as well as the activity of Ca²⁺-ATPase in the duodenum and uterus, were increased by dietary PU (p < 0.05). The genes involved in calcium transport including ERα, KCNA1, CABP-28K, and OPN in the uterus were upregulated by PU supplementation (p < 0.05). The 16S rRNA gene sequencing revealed that dietary PU supplementation could reverse the age-related decline in the relative abundance of Bacteroidota within the uterus (p < 0.05). Overall, dietary PU can improve eggshell quality and calcium transport through enhanced antioxidative defenses and mitigation of age-related uterine degeneration. Full article

To evaluate the response of broiler breeder hens submitted to different amino acid intakes of methionine+cystine, lysine, and threonine, and to determine the coefficients for egg output and body weight for maintenance. Three studies were performed using 160 broiler breeder hens housed individually in metabolic cages. A summit diet and a nitrogen-free diet were formulated. The levels ranged from 1.79 to 7.13, 2.49 to 8.3, and 2.04 to 6.79 g/kg of methionine+cystine, lysine, and threonine, respectively. The variables measured were feed intake, amino acid intake, rate of lay, egg weight, and egg output. The broken line model was used to evaluate the responses. It was verified that higher values of the rate of lay, egg weight, and egg output were observed for the higher concentrations of amino acids studied. A significant difference was observed for the variables rate of lay, egg weight, egg output, and body weight (p < 0.05) for the three amino acids evaluated. The amount of each amino acid required to produce one gram per egg was estimated at 12.4 mg, 14.5 mg, and 11.2 mg for methionine+cystine, lysine, and threonine, respectively. The values estimated by coefficient b that represent the amino acid for maintenance requirement were methionine+cystine, lysine, and threonine of 30.2, 32.2, and 42.4 mg/kg BW, respectively. The coefficients may be used to design additional models to study requirements nutrition in broiler breeders, allowing a better understanding of how these birds respond to different dietary amino acids. Full article

Over the years, macromycete fungi have been used as a source of food, part of religious rites and rituals, and as a medicinal remedy. Species with strong health-promoting potential include Hericium erinaceus, Cordyceps militaris, Ganoderma lucidum, Pleurotus ostreatus, Flammulina velutipes, and Inonotus obliquus. These species contain many bioactive compounds, including β-glucans, endo- and exogenous amino acids, polyphenols, terpenoids, sterols, B vitamins, minerals, and lovastatin. The level of some biologically active substances is species-specific, e.g., hericenones and erinacines, which have neuroprotective properties, and supporting the production of nerve growth factor in the brain for Hericium erinaceus. Due to their high health-promoting potential, mushrooms and substances isolated from them have found applications in livestock nutrition, improving their welfare and productivity. This phenomenon may be of particular importance in the nutrition of laying hens and broiler chickens, where an increase in pathogen resistance to antibiotics has been observed in recent years. Gallus gallus domesticus is a key farm animal for meat and egg production, so the search for new compounds to support bird health is important for food safety. Studies conducted to date indicate that feed supplementation with mushrooms has a beneficial effect on, among other things, bird weight gain; bone mineralisation; and meat and egg quality, including the lipid profile and protein content and shell thickness, and promotes the development of beneficial microbiota, thereby increasing immunity. Full article

This study evaluated the production performance and egg quality of Lohmann Brown laying hens fed diets containing different levels of Corn Bran with Solubles (CBS). A total of 144 hens aged 44 weeks were assigned to three treatments in a completely randomized design, with eight replicates per treatment and six birds per replicate. The experimental treatments included diets with CBS inclusion levels of 0%, 5%, and 10%. The experiment lasted 84 days (44 to 55 weeks of age). Data were analyzed via one-way ANOVA, with mean differences evaluated using Tukey’s HSD test (α = 0.05). No significant effects were observed for laying rate, feed intake, feed conversion ratio, or egg mass (p > 0.05). However, egg quality parameters such as shell percentage, shell weight per unit surface area (SWUSA), and yolk color were influenced by the treatments (p < 0.05). Hens fed diets with 5% CBS exhibited higher shell percentage and SWUSA compared to those on the 0% CBS diet. Yolk color intensity increased with higher CBS inclusion levels. In conclusion, incorporating up to 10% CBS in corn–soybean meal diets for laying hens can enhance egg yolk pigmentation. Notably, including 5% CBS improves eggshell quality. Full article

The objective of this study was to evaluate the effect of two limestone granulometries (0.568 and 1.943 mm) and different levels of vitamin D3 (12.5 g and 25 g) on the thermoregulatory and behavioral responses of replacement pullets. Lohman brown lineage pullets (270 birds), with an average weight of 639.60 g ± 6.05 and an initial age of eight weeks, were used in this study. The experimental design adopted was completely randomized in a 2 × 2 × 2 + 1 factorial arrangement (2 limestone granulometries × 2 levels of vitamin D3 × 2 shifts). The respiratory rate (RR), cloaca temperature (CT), feather surface temperature (FST) and featherless surface temperature (FLST) were higher in the afternoon (p < 0.05), while the thermal gradient (TG) was higher in the morning (p < 0.05). Birds supplemented with different limestone granulometries and different levels of vitamin D3 showed similar thermoregulatory and behavioral responses. The “eating” activity was more frequent in the morning, while in the afternoon, the birds remained seated for longer (p < 0.05). The dietary supplementation with different limestone granulometries and vitamin levels did not impair thermoregulation even at higher temperatures. Regardless of the level of vitamin D3, they showed a better expression of welfare-related behavioral activities in the morning in the semiarid region. Full article

This study aimed to investigate the effects of baicalin and citric acid on egg production performance, egg quality, and the intestinal morphology and function of laying hens. A total of 600 Hy-Line Brown laying hens, 59 weeks old, were randomly allocated to four dietary treatments, with 10 replicates per treatment and 15 hens per replicate. The control group was fed a basal diet, while the other three groups were fed the basal diet supplemented with 150 mg/kg baicalin (B), 2000 mg/kg citric acid (CA), or 150 mg/kg baicalin plus 2000 mg/kg citric acid (B + CA), respectively. The experimental period lasted for 12 weeks, and the results indicated that neither the individual addition nor the combined application of baicalin and citric acid had a significant impact on the laying performance. However, compared with the control group, the baicalin and/or citric acid supplementation significantly increased the eggshell strength and Haugh unit. Additionally, the combination of baicalin and citric acid significantly increased the villus height and the villus height/crypt depth ratio in the duodenum and jejunum. It also enhanced the population of beneficial bacteria, such as Lactobacillus and Bifidobacterium, in the cecum and improved the activity of intestinal digestive enzymes, primarily disaccharidases. Furthermore, the addition of baicalin to the diet significantly increased the content of Secretory Immunoglobulin A in the ileum and jejunum after 12 weeks of feeding. These results suggest that the combination of baicalin and citric acid had a synergistic effect on the improvement of egg quality and intestinal morphology and function in laying hens. Overall, our findings provide important insights into the potential benefits of supplementing baicalin and citric acid in the diet of laying hens and may have practical implications for improving egg quality and poultry health status. Full article

The objective of this experiment was to investigate the effects of tartary buckwheat flavonoids (TBF) and 25-hydroxyvitamin D₃ (25-OHD) on fatty liver syndrome (FLS) in laying hens. A total of 450 35-wk-old Lohmann laying hens were selected and randomly divided into five groups, with six replicates per treatment and 15 laying hens in each replicate. The control group was fed a corn-soybean meal basal diet. The FLS group was fed a high- energy–low-protein (HELP) diet, and the other three experimental groups were fed HELP diets supplemented with 60 mg/kg TBF, 69 μg/kg 25-OHD, and 60 mg/kg TBF plus 69 μg/kg 25-OHD, respectively. The experiment lasted 8 weeks. The results demonstrated that feeding laying hens with a HELP diet led to a significant accumulation of fat in their livers, liver enlargement and yellowing, as well as a decline in liver antioxidant capacity and an aggravation of inflammation. TBF alone, 25-OHD alone, and their combination had no effect on the laying performance of laying hens fed with a HELP diet. However, 25-OHD significantly enhanced the albumin content, eggshell strength, and eggshell thickness of eggs (p < 0.05). Compared with the HELP group, TBF, 25-OHD, or their combination reduced serum LDL-C and TG (p < 0.05). The combined treatment further lowered serum NEFA and MDA, enhanced liver SOD activity (p < 0.05), and unlike TBF alone (which reduced hepatic TG) or 25-OHD alone (which decreased liver index), reduced both liver index and hepatic TG (p < 0.05). Liver gene expression analysis showed that combined TBF and 25-OHD significantly inhibited the expression of fat synthesis-related genes (ACC, FAS, GPAT1, ChREBP1, LXRα, SREBP-1C, SREBP-2, FABP) as well as inflammation-related genes (IL-6, TNF-α, NF-κB, TLR4) (p < 0.05). At the phylum level of the cecal microbiota, TBF increased the abundance of Bacteroidota (p < 0.05), and combined TBF and 25-OHD tended to increase the abundance of Firmicutes_D. At the genus level, TBF increased the abundance of Phocaeicola_A (p < 0.05). Furthermore, TBF, 25-OHD, or their combination reduced the abundance of Faecalibacterium (p < 0.05). These findings suggest that combined TBF and 25-OHD mitigates FLS in laying hens potentially through remodeling gut microbiota and maintaining lipid metabolic homeostasis. Full article

Camelina sativa (CS) is an emerging sustainable oilseed crop with interesting feed application potentialities. The research assessed the potentiality of Camelina sativa (CS) in the diet for free-range laying hens, aiming at reaching a nutritional claim. To this purpose, two feeding groups of hens (n = 100 Livorno hens, n = 25 hens/pen) were farmed outdoor and received either a Control diet, which was a commercial diet for laying hens, or a CS diet. The latter was formulated to include the 5% CS cake and 1% CS oil, replacing conventional feedstuffs. Diets were isoprotein and isoenergy and were available ad libitum throughout the laying period (February–September). At day 1, n = 12 eggs/diet were sampled to assess the initial proximate composition and FA profile. Every 7 days the sampling was repeated to analyze the eggs’ FA profile, up to day 35. At the end of the laying season, n = 6 hens/dietary treatment were slaughtered and subjected to meat quality evaluations. Results highlighted that a 28-day feeding was the period required to obtain 227 mg of C18:3 n-3 and 81 mg of C20:5 n-3 + C22:6 n-3/100 g egg, whereas a further 7 days of feeding trial were ineffective in further enhancing the omega-3 FA content of eggs. CS eggs were comparable to Control ones for overall physical traits, proximate composition, and shelf-life. In addition, at the end of the laying period, the meat of CS hens was also found to be healthier than that of Control ones, thanks to a higher omega-3 FA proportion (p < 0.01), which was, however, not sufficient to reach any nutritional claim. Instead, the proximate composition of CS meat was overall comparable to Control hens. In conclusion, the present research demonstrated that feeding Camelina sativa meal and oil to laying hens is feasible and allows to reach the nutritional claim in eggs “rich in omega-3 FA” after a feeding period of 28 days, without any negative effects on other eggs’ quality trials. Camelina sativa can thus be defined as a promising sustainable feedstuff for the poultry sector for diversification purposes and to enhance the nutritional quality of eggs. Full article

Egg yolk immunoglobulin Y (IgY) possesses advantages such as low cost, easy availability, simple preparation, high antigen specificity, absence of drug residues, and compliance with animal welfare standards, making it an environmentally friendly and safe alternative to antibiotics. This research utilizes IgY antibody technology to develop a multivalent passive immune vaccine for major pathogenic bacteria in aquaculture. In this study, IgY antibodies against live Shewanella xiamenensis (LSX-IgY) and inactivated S. xiamenensis (ISX-IgY) were prepared by immunizing laying hens, and passive immunization protection experiments were conducted in Carassius auratus infected with S. xiamenensis and Aeromonas hydrophila. The passive immunization protection rates of LSX-IgY and ISX-IgY against S. xiamenensis were 63.64% and 72.73%, respectively, and the passive cross-protection rates against A. hydrophila were 50% and 71.43%, respectively. Further, C. auratus sera could specifically bind to S. xiamenensis or A. hydrophila in vitro, and the phagocytic activity of leukocytes was increased. LSX-IgY and ISX-IgY could reduce the bacterial load in the C. auratus kidneys. Meanwhile, they could significantly reduce the levels of antioxidant factors in serum and inhibit the mRNA expression of inflammation-related factors in the kidneys and spleens. Additionally, histopathology and immunofluorescence analysis showed that both IgY preparations preserved tissue integrity and reduced the expression of apoptosis factor (p53) and DNA damage factor (γH2A.X) of visceral organs, respectively. In summary, LSX-IgY and ISX-IgY can combat various bacterial infections, with no significant difference between the two. Additionally, inactivated bacterial immunization is more aligned with animal welfare standards for laying hens. Therefore, ISX-IgY is expected to serve as a multivalent vaccine against major aquaculture pathogens. Full article

The objective of this study was to determine the effects of two levels of a precision biotic (PB) within a reduced CP diet for performance, digestibility, and blood biomarkers in Dekalb White laying hens from 24 to 42 weeks of age. A total of four diets were fed: (1) an industry-standard positive control (PC) diet with a formulated CP level of 17.5%; (2) a negative control (NC) diet with a formulated CP level of 15.5%; (3) NC with 0.5 kg/ton PB (NC+PB1); (4) NC with 0.7 kg/ton PB (NC+PB2). The NC diet decreased hen–day egg production compared to the PC diet, and supplementation with both levels of PB led to intermediate levels of production. There was a similar trend for the feed conversion ratio (FCR), measured in kilograms of feed per dozen eggs. Feed cost was lower in the reduced CP diets compared to the PC. Apparent total tract digestibility was decreased with PB supplementation without differences in apparent ileal digestibility. The increased plasma uric acid levels in the NC+PB2 group suggest a shift in protein metabolism toward higher efficiency in ammonia detoxification. While more research is needed on PB, this research suggests that supplementation with PB in laying hens could potentially improve performance parameters. Full article

Background: Reliable and non-invasive methods for assessing welfare in poultry are essential for improving evidence-based welfare monitoring and advancing management practices in commercial production systems. The iris-to-pupil (IP) ratio, previously validated by our group in primates and cattle, reflects autonomic nervous system balance and may serve as a physiological indicator of stress in laying hens. This study evaluated the utility of the IP ratio under field conditions across diverse commercial layer housing systems. Materials and Methods: In total, 296 laying hens (Lohmann Brown, n = 269; White Leghorn, n = 27) were studied across four locations in Canada housed under different systems: Guelph (indoor; pen), Spring Island (outdoor and scratch; organic), Ottawa (outdoor, indoor and scratch; free-range), and Toronto (outdoor and hobby; free-range). High-resolution photographs of the eye were taken under ambient lighting. Light intensity was measured using the light meter app. The IP ratio was calculated using NIH ImageJ software (Version 1.54p). Statistical analysis included one-way ANOVA and linear regression using GraphPad Prism (Version 5). Results: Birds housed outdoors had the highest IP ratios, followed by those in scratch systems, while indoor and pen-housed birds had the lowest IP ratios (p < 0.001). Subgroup analyses of birds in Ottawa and Spring Island farms confirmed significantly higher IP ratios in outdoor environments compared to indoor and scratch systems (p < 0.001). The IP ratio correlated weakly with ambient light intensity (r² = 0.25) and age (r² = 0.05), indicating minimal influence of these variables. Although White Leghorn hens showed lower IP ratios than Lohmann Browns, this difference was confounded by housing type; all White Leghorns were housed in pens. Thus, housing system but not breed was the primary driver of IP variation. Conclusions: The IP ratio is a robust, non-invasive physiological marker of welfare assessment in laying hens, sensitive to housing environment but minimally influenced by light or age. Its potential for integration with digital imaging technologies supports its use in scalable welfare assessment protocols. Full article

Hemp (Cannabis sativa L.) products have gained attention in poultry nutrition for their rich content of polyunsaturated fatty acids (PUFAs), bioactive compounds, and potential functional benefits. However, findings on their impact on laying-hen performance, egg quality, and yolk fatty acid profiles have been inconsistent. This meta-analysis aimed to evaluate the effects of dietary hemp products on laying-hen performance, egg quality traits, and yolk fatty acid composition, while exploring potential sources of heterogeneity across studies. A comprehensive literature search identified 21 studies that met the inclusion criteria. A random-effects model was used to calculate standardized mean differences (SMDs) with 95% confidence intervals (CIs) for various outcomes, including production performance, egg quality, and yolk fatty acid profiles. Subgroup and meta-regression analyses assessed the influence of factors such as inclusion level, hen age, and hemp product type. The results showed that hemp supplementation had no significant effect on hen-day production, egg mass, feed conversion ratio, or feed intake. However, yolk redness (SMD = 4.40; 95% CI: 2.46, 6.33; p < 0.001) and yellowness (SMD = 4.45; 95% CI: 2.75, 6.16; p < 0.001) were significantly enhanced. Hemp feeding also increased n-3 PUFA levels in egg yolk, including C18:3n3, C20:5n3, and C22:6n3, while reducing saturated and monounsaturated fatty acids. Subgroup analysis indicated that inclusion levels > 10% and hen age ≤ 25 weeks were associated with slight reductions in hen-day production, whereas older hens (>25 weeks) showed increased egg weight. In conclusion, hemp products can enrich yolk pigmentation and n-3 PUFA content in eggs, supporting the production of functional, value-added eggs without compromising the laying-hen performance. Full article

This experiment aimed to investigate the appropriate level of degossypolized cottonseed protein (DGCP) in the diet of laying hens. A total of 600 49-week-old Lohmann pink laying hens were allocated to five treatments, with six replicates per treatment and 20 birds per replicate. The control group was fed a corn-soybean meal basal diet. Four experimental diets were formulated by replacing 25%, 50%, 75%, and 100% of the soybean meal protein-equivalent capacity with DGCP, where 100% replacement corresponded to the maximum safe inclusion of DGCP. The study period lasted for 8 weeks. The results showed that the feed intake, average egg weight, egg mass, laying rate, and the albumen percentage were significantly reduced in the 100% DGCP group (p < 0.05). Plasma uric acid (UA), total cholesterol (TC), triglyceride (TG), and potassium (K) levels were significantly lower (p < 0.05), and depth of crypt (CD) was significantly higher (p < 0.05) in the 100% DGCP group. The DGCP diet linearly increased the relative abundance of Bacteroidota and Bacteroide and significantly increased the relative abundance of Desulfobacterotas in the cecum contents compared to the control group (p < 0.05). The ACE and Chao1 indices in both the control group and the 100% DGCP group were significantly decreased (p < 0.05). In conclusion, the dietary addition of DGCP can reach up to 114.6 g/kg. Full article

The objective of this study was to evaluate the effects of various feed additives on odor emissions, gut health, and stress responses in laying hens fed low-protein diets. Four commercially available functional feed additives (Bacillus subtilis, protease, saponin, and thyme-based essential oil) were selected for this study. A total of 288 Hy-Line brown laying hens aged 49 weeks were randomly fed on one of six experiment diets: a 16% standard crude protein diet, a 12% low-crude-protein (LCP) diet, and LCP diets supplemented with Bacillus-based probiotic, protease, saponin, or thyme-based essential oils prepared for 8 weeks. Each treatment had eight replicates with six birds per replicate. Lowering crude protein levels affected the laying performance, nitrogen balance, odor production (i.e., ammonia), and nutrient digestibility but did not alter eggshell quality or fecal short-chain fatty acids. Dietary additives added into the LCP diet did not affect the laying performance, egg qualities, and nitrogen balance but increased crude ash digestibility compared with the LCP-diet-fed laying hens. Branched-chain fatty acids tended to be higher in all laying hens fed low-CP diets, irrespective of feed additives. Notably, low vs. standard protein diets tended to increase yolk corticosterone levels, which is an indicator of stress responses in chickens. This low-CP-mediated increase in yolk corticosterone was partially decreased by 20.8–48.6% on average, depending on the additives used. Our study suggests that low-protein diets could effectively lower nitrogen excretion and odor emissions. However, adding dietary additives into low-protein diets has minimal effects on low-CP-diet-fed laying hens, which needs further studies to clarify the role of low-crude-protein diets and dietary additives in modulating hindgut fermentation via shaping the gut microbiota and stress responses of laying hens. Full article

Laminosioptes cysticola (Vizioli, 1870), a tissue-dwelling mite responsible for nodular acariasis in birds, was identified from two hens reared in a rural backyard flock in Umbria, Italy. Adult mites were found in the subcutaneous tissue and on the serosal surface of various internal organs. Larval and first- and second-stage nymphal forms were observed beneath the skin and near the trachea and esophageal serosa. By comparing the existing literature with that reported in the present study, we propose a hypothetical reconstruction of the parasite’s life cycle. It is postulated that the entry of L. cysticola occurs through the cervical skin, where adults mate and larviparous females give birth to larvae. These larvae migrate into the loose connective tissues surrounding the trachea and esophagus, where they develop into nymphs. The immature forms then progress along the esophagus and trachea to reach the thoracic and abdominal cavities, colonizing the serosal surfaces of visceral organs. It remains unclear whether, or how, the mites return to the subcutaneous tissues to complete their maturation. Senescent specimens degenerate within the subcutis, where they are encased by a granulomatous inflammatory reaction that leads to the formation of characteristic calcified nodules. Full article