Search Results (75)

Laying hens require lighting for proper development and reproduction. There is limited research on the effects that lighting types have on birds’ welfare quality. A novel lighting source, Pulsed Alternating Wavelength System (PAWS), is being evaluated in the industry that claims to improve birds’ growth rate, decrease age at first egg, and decrease aggressive and nervous behaviors. Understanding how PAWS effects hen’s welfare, both physically and physiologically, is critical if this technology is to be adopted by industry. The project evaluated the effects of two PAWS lighting recipes on neurotransmitter turnover and welfare quality of commercial, conventionally caged laying hens. Three flocks of White leghorn hens (control [fluorescent lights] and two PAWS flocks [PAWS1 and PAWS2]) were sampled from 22 to 70 weeks of age, depending on the flock. The physical welfare of 50 hens per flock and neurotransmitter turnover of 10 hens per flock were assessed at each timepoint. The majority of welfare quality parameters were influenced by age as opposed to lighting type. No differences in dopamine turnover were observed. The hens housed under PAWS1 had reduced serotonin turnover, thus increased serotonin activity, and PAWS2 hens had improved keel bone damage scores; both indicative of improved welfare compared to control hens. The novel lighting may be beneficial to layer welfare, which may lead to increased longevity and productivity. Implementation in cage-free housing should be explored to delve into potential behavioral differences that could further influence welfare outcomes. Full article

Intensive farming methods have improved productivity, but public concerns have arisen regarding the welfare of production animals, particularly laying hens, and consumers demand higher animal welfare standards in all animal production systems. This study evaluated the impact of conventional cage (CC) versus cage-free (CF) housing systems on the gene expression of some peptide hormones regulating food intake along the gut–brain axis in laying hens at 80 wks. Sixty thousand Hy-Line Brown hens were reared under commercial farm conditions until week 15. At 16 wks, hens were randomly assigned into two housing systems: CC (450 cm²/bird) and CF (1111 cm²/bird). At week 80, hypothalamic, proventricular, duodenal, jejunal, and ileal tissues were sampled from six hens per system for qPCR analysis. Relative mRNA transcript levels of peptide hormones involved in the regulation of food intake (GHRL, Ghsr, NPY, AGRP, POMC, CCK, CART, CRH, MC4R, MC1R, MC5R) were quantified by qPCR using the most stable reference genes. CC hens exhibited upregulation of duodenal anorexigenic genes (POMC, CCK, CART, CRH) and stress-related MC4R, while CF hens showed higher ileal expression of foraging-related AGRP. No differences were observed in orexigenic peptides (GHRL/Ghsr, NPY). These findings suggest that housing systems differentially modulate gut–brain axis signaling. Specifically, CC environments appear to upregulate satiety signals, whereas CF systems seem to enhance the expression of genes linked to foraging behavior. Full article

The omega-3 polyunsaturated fatty acids (n-3 PUFA) in animal-derived foods are increasingly important for human health. Sacha inchi (Plukenetia volubilis L.), rich in n-3 PUFA, is a promising feedstuff for producing n-3 PUFA-enriched animal products. However, research on dietary Sacha inchi oil (SIO) supplementation in laying hens remains limited. Therefore, this study aimed to evaluate the effects of SIO on production performance, egg quality, and yolk fatty acid (FA) composition in laying hens. A total of 192 hybrid hens [(♂ White Leghorn × ♀ Egyptian Fayoumi); initial body weight: 1910 ± 22.14 g; age: 25 weeks old] were randomly assigned one of the four diets: a basal diet (CONT), and three tested diets based on CONT with the addition of 1.5%, 3.0%, and 4.5% SIO (as-feed basis) (SI15, SI30, and SI45, respectively). Each dietary treatment included 48 hens housed in 12 battery cages for 56 days with 4 birds per cage. Increasing dietary SIO levels significantly reduced average daily feed intake (p < 0.05). Egg yolk weight linearly increased (p < 0.05) with higher SIO inclusion, while other egg quality traits were unaffected. SIO supplementation significantly increased (p = 0.001) yolk n-3 PUFA level (from 0.79% to 8.29% on day 28, and from 0.87% to 9.13% on day 56) and substantially reduced the n-6/n-3 PUFA ratio by about nine-fold on both 28 and 56 days. In conclusion, SIO is a promising n-3 PUFA-rich feed ingredient for egg production. Adding 3.0–4.5% SIO in laying hen diets can enhance egg yolk weight and n-3 PUFA level while reducing feed intake without negatively affecting egg production or quality. Full article

Peanuts and poultry production predominate within the southeast US. Hence, the objective of this study was to determine the dietary effects of unblanched (skin-intact) high-oleic peanuts (HOPNs) and peanut skins (PN skins) on layer performance, egg quality, and fatty acid profile. To meet these objectives, 200 hens were randomly assigned to four treatments, housed in floor pens, and fed ad libitum for 8 weeks a control, HOPN (24%), PN Skin (3%), or 2.5% oleic acid (OA) diet. All empirical data was statistically analyzed for variance at the p < 0.05 level. Hens fed the HOPN and PN Skin diets had heavier body weights relative to the controls at week 8 (p < 0.05). Layers fed the HOPN treatment had poor FCR and smaller egg weights with lower levels of polyunsaturated fatty acids relative to the controls (p < 0.05). Hens fed the PN Skin treatment had similar performance parameters, egg quality, and egg chemistry relative to the controls over the 8-week study. These results imply that PN skins may be an acceptable poultry feed additive without adverse effects on performance, egg quality, or egg lipid chemistry. Also, these results demonstrate the potential value-added utilization of PN skins, a waste by-product of the peanut industry, as a layer feed ingredient. Full article

Non-alcoholic fatty liver disease (NAFLD) has emerged as a significant metabolic disorder in modern poultry production, particularly affecting high-yielding laying hens. This condition compromises bird welfare, productivity, and economic sustainability within commercial farming systems. This narrative review provides a comprehensive overview of the underlying mechanisms through which hepatic lipid accumulation, metabolic dysfunctions, hormonal imbalances, genetic susceptibilities, and environmental stress contribute to the development of NAFLD. The multifactorial nature of NAFLD is explored through a critical assessment of the literature, highlighting the influence of diet composition, management practices, and physiological demands associated with intensive egg production. Emphasis is placed on recent advancements in nutritional modulation, selective breeding, and housing improvements aimed at prevention and mitigation of NAFLD. Furthermore, the review identifies key research gaps, including limited understanding of epigenetic influences and the long-term efficacy of intervention strategies. An integrative framework is advocated, synergizing genetics, nutrition, and environmental optimization to effectively address the complexity of NAFLD in poultry and supports the development of resilient production systems. The insights presented aims to inform both future research and practical applications for enhancing poultry health and performance. Full article

Particulate matter (PM) is a significant air pollutant in modern egg production. However, high-quality PM data from commercial egg farms are still very limited. A 6-month study, covering both cold and hot seasons, measured PM₁₀ concentrations and emissions in a 140,000-hen commercial laying hen house in the Midwest USA. An advanced measurement system was implemented for continuous and real-time monitoring, collecting data from 67 online instruments and sensors. The study generated 4318 h of valid PM₁₀ data, with 97.8% data completeness. The average daily mean (ADM) PM₁₀ concentration in the house exhaust air, standardized to 20 °C and 1 atm, was 236 ± 162 (ADM ± standard deviation) µg m⁻³. The ADM net PM₁₀ emission was 18.9 ± 2.2 mg d⁻¹ hen⁻¹. Increasing outdoor temperatures were correlated with decreased indoor PM₁₀ concentrations but increased overall emissions. Comparison with the ADM emission of 12.4 ± 13.3 mg d⁻¹ hen⁻¹ from the same house during a previous six-month study in 2004–2005 revealed that artificial hen molting in this study increased PM₁₀ concentrations and emissions. Extrapolating the ADM PM₁₀ emission from the house, the ADM PM₁₀ emission from the entire egg farm was estimated at 35.6 ± 31.1 kg d⁻¹ (or 35.6 ± 4.5 kg d⁻¹ with a 95% confidence interval). This study provides valuable insights into air quality in animal agriculture and contributes high-quality and real-world data for use in data-driven approaches such as artificial intelligence, machine learning, data mining, and big data analytics. Full article

Outdoor access, often referred to as pop holes, is widely used to improve the production and welfare of hens. Such cage-free environments present an opportunity for precision flock management via best environmental control practices. However, outdoor access disrupts the integrity of the indoor environment, including properly planned ventilation. Moreover, complaints exist that hens do not use the holes to access the outdoor environment due to the strong incoming airflow through the outdoor access, as they behave as uncontrolled air inlets in a negative pressure ventilation system. As the egg industry transitions to cage-free systems, there is an urgent need for validated computational fluid dynamics (CFD) models to optimize ventilation strategies that balance animal welfare, environmental control, and production efficiency. We developed and validated CFD models of a cage-free hen house with outdoor access by specifying real-world conditions, including two exhaust fans, sidewall ventilation inlets, wire-meshed pens, outdoor access, and plenum inlets. The simulations of four ventilation scenarios predict the measured air flow velocity with an error of less than 50% for three of the scenarios, and the simulations predict temperature with an error of less than 6% for all scenarios. Plenum-based systems outperformed sidewall systems by up to 136.3 air changes per hour, while positive pressure ventilation effectively mitigated disruptions to outdoor access. We expect that knowledge of improved ventilation strategy will help the egg industry improve the welfare of hens cost-effectively. Full article

Rooster behavior and activity are critical for egg fertility and hatchability in broiler and layer breeder houses. Desirable roosters are expected to have good leg health, reach sexual maturity, be productive, and show less aggression toward females during mating. However, not all roosters are desirable, and low-productive roosters should be removed and replaced. The objectives of this study were to apply an object detection model based on deep learning to identify hens and roosters based on phenotypic characteristics, such as comb size and body size, in a cage-free (CF) environment, and to compare the performance metrics among the applied models. Six roosters were mixed with 200 Lohmann LSL Lite hens during the pre-peak phase in a CF research facility and were marked with different identifications. Deep learning methods, such as You Only Look Once (YOLO) models, were innovated and trained (based on a comb size of up to 2500 images) for the identification of male and female chickens based on comb size and body features. The performance matrices of the YOLOv5u and YOLOv11 models, including precision, recall, mean average precision (mAP), and F1 score, were statistically compared for hen and rooster detection using a one-way ANOVA test at a significance level of p < 0.05. For rooster detection based on comb size, YOLOv5lu, and YOLOv11x variants performed the best among the five variants of each model, with YOLOv5lu achieving a precision of 87.7%, recall of 56.3%, and mAP@0.50 of 60.1%, while YOLOv11x achieved a precision of 86.7%, recall of 65.3%, and mAP@0.50 of 61%. For rooster detection based on body size, YOLOv5xu, and YOLOv11m outperformed other variants, with YOLOv5xu achieving a precision of 88.9%, recall of 77.7%, and mAP@0.50 of 82.3%, while YOLOv11m achieved a precision of 89.0%, recall of 78.8%, and mAP@0.50 of 82.6%. This study provides a reference for automatic rooster monitoring based on comb and body size and offers further opportunities for tracking the activities of roosters in a poultry breeder farm for performance evaluation and genetic selection in the future. Full article

Lipid matrix microencapsulation is hypothesized to improve bioavailability for broiler breeders supplemented with normal and protect against excessive levels of inorganic trace minerals. At 27 weeks (wk), nine females and two males were assigned to each of the 12 floor pens. Each pen was randomly assigned to dietary treatments (trt) in a factorial arrangement of two mineral premix forms, free (FRTM) and microencapsulated (MITM), and two mineral premix supplement dosages (100% and 300% of Aviagen recommendations). At 55 wk termination, 15 hens/trt were randomly selected to assess tibia and jejunum morphology. Breeders receiving MITM improved hen day % (HD %), hen housed (HH%), and FCR but produced the lightest chicks at hatch. The TM form had no significant effect on histology, but TM 100% had greater villus height (VH), crypt depth (CD), and villi area than TM 300% (p < 0.5). No significant treatment effects on bone weight, length, and bone mass density were observed. However, MITM treatments increased tibia thickness, and FRTM supplementation increased ash% and Cu content. Hens fed 300% TM had higher bone Mn content than 100% TM, whereas hens fed MI100 had the highest Fe content. Feeding lipid matrix microencapsulated trace minerals to broiler breeders does have positive impacts on the production of eggs, but no effects were observed in the histomorphology of the jejunum or tibia bone parameters. Full article

A modified AM/PM strategy was evaluated in this study by supplementing calcium (Ca) in afternoon/evening (PM) drinking water instead of feed, offering an alternative to supplying two diets. A 10-week trial was conducted with 288 Hy-Line Brown hens (56 weeks old) housed on the floor in 18 pens (16 hens per pen; 9 replicate pens per treatment). The control diet contained 4.5% Ca, while the AM/PM treatment had 4.1% in feed with additional Ca and vitamin D supplemented through PM drinking water, with other nutrients kept constant in both diets. Daily egg production and weekly feed and water consumption were recorded. Hen weight, welfare scores, and egg quality were assessed at weeks 5 and 10. Blood, ileal digesta, and tibia samples were collected (from 4 hens/pen) at week 10 for serum Ca and vitamin D, digestibility, and bone analyses. Liver and kidney weights, as well as keel bone scores, were also recorded at week 10. Hens on the AM/PM diet consumed significantly less water (171.23 vs. 196.85 mL/bird/day; p < 0.001) and had a significantly higher serum vitamin D (27.59 vs. 22.64 ng/mL; p = 0.014), with a tendency towards elevated serum calcium levels (31.99 vs. 29.74 mg/dL; p = 0.089) compared to the control group. No differences in laying performance, co-efficient of variance (CV%) in individual hen and egg weight, liver and kidney weight, or keel and tibia characteristics were observed between treatments (p > 0.05). Similarly, there was no treatment effect on egg quality, and welfare parameters at week 5 and 10, except for smaller eggs (57.13 vs. 57.96; p = 0.015), and reduced chest (0.96 vs. 1.16; p = 0.028) and belly feather damage (1.34 vs. 1.55; p = 0.021), respectively, in hens of the AM/PM treatment compared to the control at week 10. The AM/PM treatment improved ileal digestible energy as is (9.00 vs. 8.22; p = 0.022) and as dry matter (10.00 vs. 9.06; p = 0.014) compared to the control one. Overall, it demonstrated comparable performance to the control, with added benefits of reduced water intake, better feather condition and vitamin D level and energy digestibility. Full article

A social network is a group of individuals forming a non-random social structure where the number of interactions systematically vary among individuals. The Red Junglefowl, the ancestor of all domesticated chickens, has been shown to form social structures within a larger group; however, how poultry in egg production are socially organised is poorly understood. Egg layers in groups of thousands of individuals are suggested to either, just as Red Junglefowl, form subgroups or to lose social affiliations and replace these with a system of social tolerance. In this case study, a stable group of 20 laying hens with known genetic relationships housed in an outdoor aviary were observed for 3 h per day, during 20 days, in order to determine the social structure in the group. Social affiliations and centralisation measurements were assessed by proximity. The results show that some individuals were consistently more centralised compared to others, which indicates a stable individual variation in sociality. Furthermore, no individual spent more than 10% of her total number of interactions with a particular individual, i.e., little consistency in social affiliations could be found. The results of this case study support the theory of a higher social tolerance rather than a consistent social organisation in domesticated egg layers. Full article

With the aim to characterise the situation of the subsector, 25 poultry farms of the endangered native Utrerana chicken egg-laying-oriented breed (Gallus gallus Linnaeus, 1758) were surveyed in Andalusia (southern Spain) from 2021 to 2023 to investigate the structure of the farms, number of birds, health status, feeding management, and marketing of their products. It was found that the pace of foundation of Utrerana chicken farms accelerated from 2009, and most of the farms were concentrated in the province of Seville. Only 40% of the farms were legally registered. This breed is raised on small farms mainly dedicated to self-supply and raising birds for conformation and their aesthetic values, with limited marketing of eggs and meat, with facilities consisting often of one poultry house and one outdoor enclosure, and with a low number of laying hens per farm (53.5 on average). Current productivity is low, with an average of 139 eggs per hen per year, but hens have a long reproductive lifespan, averaging 4 years. The Partridge variety of the breed was the most common, followed by the Black-barred and Black varieties, while the White variety was very scarce, with only 31 specimens in total. Two-thirds of the farmers also raised other breeds of chickens, in addition to the Utrerana. The management and production system was free-range or backyard, with a certain proximity to the requirements of European Union-certified organic production with regard to stocking densities and generally with a good sanitary status, respect for welfare, and implementation of biosecurity measures on the farms. The feeding of the chickens was based on grazing in outdoor enclosures and on the provision of grains and compound feed, with 40.0% of farmers using commercial compound feed and half preparing feed themselves. Two-thirds of the farmers were affiliated with the National Association of Utrerana Chicken Breeders (“Asociación Nacional de Criadores de Gallinas Utreranas”, ANCGU, in Spanish); almost half of them took part with their birds in fairs and conformation shows, such as the Utrerana Chicken Fair held in Utrera (province of Seville) and more than a quarter of them have sold live birds of the breed at these fairs. The farmers carry out few promotional and advertising activities for their farms and products, predominantly by using social networks, and the market area reached is mainly local. In conclusion, this research has shown that the current alternative production system for Utrerana chicken is similar to that of the hens that originated the breed and consists of a few amateur farms, with a small number of birds, distributed mainly throughout the Andalusian countryside. It has been highlighted that there is a need for the livestock authorities to implement programmes for supporting farmers and promoting the breeding of this endangered avian breed, native to the Spanish zoogenetic heritage. Full article

Heat stress can disrupt the balance between the heat poultry release into the environment and the heat they generate. Pequi oil has antioxidant properties, which may mitigate the heat stress effects. This study aimed to investigate the response of laying hens to pequi oil supplementation under heat stress using a proteomic approach. A total of 96 Lohmann White laying hens with 26 weeks old were housed in a completely randomized design with a 2 × 2 factorial arrangement. They were housed in two climate chambers, thermal comfort temperature ± 24.04 °C with the relative humidity ± 66.35 and heat stress (HS) ± 31.26 °C with the relative humidity ± 60.62. They were fed two diets: a control diet (CON), basal diet (BD) without additives, and with Pequi oil (PO), BD + 0.6% PO. After 84 days, plasma samples were analyzed using Shotgun and LC-MS/MS. Proteins related to anti-inflammation, transport, and the immune system were differentially expressed in hens fed PO and CON under heat stress compared to those in thermoneutral environments. This helps protect against oxidative stress and may support the body’s ability to manage heat-induced damage, stabilizing protein expression under stress conditions. The ovotransferrin proteins, fibrinogen isoforms, apolipoprotein A-I, Proteasome activator subunit 4, Transthyretin, and the enzyme serine Peptidase Inhibitor_Kazal Type 5, which presented Upregulated (Up) equal to 1, present characteristics that may be crucial for enhancing the adaptive responses of hens to thermal stress, thereby increasing their tolerance and minimizing the negative effects of heat on egg production. The data presented in this manuscript provides new insights into the plasma proteome alterations of laying hens fed a diet supplemented with pequi oil during heat stress challenges. Full article

Low-pressure systems (LPSs) are among the most critical weather systems, producing excessive precipitation that causes air temperatures to drop and rise considerably. Acute temperature changes directly affect poultry feed intake (FI) and laying performance. To explore the effects of LPSs on hens, the parameters of air temperature, relative humidity, egg production, and feed utilization efficiency were evaluated during different LPSs in three houses. Results indicated that about 2.8 ± 0.7 d, 2.4 ± 0.5 d, and 2.4 ± 0.5 d before the LPS landfall in houses 1, 2, and 3, respectively, the indoor air temperature started to decrease, with the average decreases being 1.7 °C ± 0.4 °C, 2.4 °C ± 0.6 °C, and 1.8 °C ± 0.4 °C, respectively. Significant differences were observed between different LPSs for reducing indoor air temperature (p < 0.05) in the three houses. In house 1, the egg production rates (EPRs) were decreased by 6.6% and 1.1% when LPSs 1 and 2 landed. The average egg weight (AEW) and FI during the LPS landfall were significantly higher than those before the LPS landfall (p < 0.01). Under successive LPSs landfall in the three houses, the EPRs initially reduced by 3.9%, 4.0%, and 0.5%, respectively, but the second LPS event increased the EPRs by 1.8%, 5.3%, and 1.0%, respectively. Furthermore, the LPS landfall increased the feed conversion ratio (FCR_e) in the three houses, all above 2.00. In conclusion, LPSs can reduce heat stress, lower the EPRs, and lead to higher FI, FCR_e, and AEW. Full article

Successful promotion of cage-free eggs supports a housing system offering potential for improved hen welfare. As the world’s largest egg producer and consumer, China offers much potential for welfare improvements. We examined 10 Chinese companies supplying cage-free eggs (four using indoor systems, six with outdoor access) to understand their strategies to promote cage-free eggs to businesses and consumers. We purposively sampled 12 employees from these companies familiar with production or sales. We conducted two–three semi-structured interviews per participant, collected public online documents (including online shops and social media content), and recorded field notes. We analyzed the data using template analysis to generate key results. Participants reported buyers being unfamiliar with ‘animal welfare’ and ‘cage-free’, but familiar with concepts associated with ‘free-range’. Participants considered three attributes when promoting cage-free eggs: price (engaging buyers who were willing to pay more), experiential attributes (e.g., taste, accommodating buyer preferences), and non-sensory credence attributes (e.g., cage-free production, improving buyers’ understanding and trust). Our results are not generalizable, though they may be transferable to similar contexts. Understanding how companies promoted cage-free eggs to buyers may help inform promotion of other animal products with welfare attributes. Simultaneous efforts are needed to ensure actual welfare improvements on farms. Full article