Search Results (142)

Zirconia ceramics are promising materials for restoration and are widely used in the field of artificial teeth. However, wear resistance affects the longevity of artificial teeth. In this study, peacock tail feather micro-textures and groove micro-textures are prepared on the surfaces of zirconia ceramics via the laser ablation technique to improve their tribological properties. The effects of micro-textures on the surface wettability and tribological properties of zirconia ceramics are studied. The micro-textures improve the surface wettability and tribological properties of zirconia ceramics. The average coefficient of friction of peacock tail feather micro-textured samples decreases by 53% compared to that of the samples without micro-textures. Different operating conditions affect the friction properties of zirconia ceramics. The samples have the best friction performance when the rotational speed, load, and acid/alkaline environment are 200 r/min, 15 N, and weakly alkaline, respectively. Furthermore, the mechanism by which surface micro-textures reduce frictional wear is as follows: the textured grooves store debris, and the bottom edge of the textured groove acts as a cutting tool to cut debris, preventing debris from scratching the surface. The micro-textures store lubricant and form a liquid film on the ceramic surface to reduce wear. Full article

This study applies the concept of the circular economy by using poultry feather waste to produce biodegradable geotextiles for environmental applications. The main goal was to assess their biodegradability, effect on soil properties, and usefulness in supporting plant growth. Three types of feather-based nonwoven fabrics were manufactured using a needle-punching method and tested under laboratory and field conditions over a 23-month period. Laboratory tests confirmed high biodegradability: Nonwoven I and III lost over 91% of their mass within 24 weeks. In field trials, plots covered with biodegradable geotextiles showed up to 266% more seedlings compared to bare soil, and plant height increased by 90% on average. The materials also improved soil moisture retention and supported microbial activity. After use, the nonwovens did not require removal and decomposed naturally, enriching the soil. The results demonstrate that feather-based geotextiles are a sustainable, effective, and locally available solution for soil protection and vegetation in difficult terrain. Full article

Flight is part of the natural behaviours of most bird species, and as a consequence, flight restraint in zoos, even for those species that are primarily ground-dwelling, encounters increasing animal welfare concerns. While previous studies on greater flamingos (Phoenicopterus roseus) and white pelicans (Pelecanus onocrotalus) have found no significant effects of flight restraint on welfare, scientific data on other species remains limited. This study investigated the welfare implications of flight restraint in white storks (Ciconia ciconia) by assessing feather corticosterone concentrations (CORTf) alongside behavioural observations. We compared CORTf values of deflighted zoo birds (n = 53) and hand-reared abandoned nestlings (n = 11) from eleven different zoos in Germany and storks in rehabilitation. These birds were wild individuals, found injured, and therefore provided an opportunity to collect feather samples (n = 70). In line with the 3R principle proposed by Russell and Burch, we employed a recently validated, less invasive feather sampling method that involves cutting feathers close to the skin. We hypothesised that CORTf would differ significantly between the wild, airworthy storks and the deflighted individuals under human care. However, we found no significant difference in CORTf regarding the ability to fly, nor did the method of flight restraint show a significant influence on CORTf. Housing facilities with significant site-specific variations emerged as the predominant factor influencing feather corticosterone concentrations. These results suggest that flight restraint does not have a noticeable direct impact on the corticosterone levels of white storks, and the behavioural observations support the reliability of these findings. This study enhances our understanding of the effects of deflighting procedures on the welfare of white storks in zoos. Full article

Stocking density is one of the major concerns in all production systems, which is why lawmakers, retailers, and consumers are increasingly concerned about this issue and its relation to animal welfare. The aim of this study was to identify if stocking density had an effect on white egg layer production, egg quality, bird health, and welfare parameters. For this study, five stocking densities were evaluated in colony cages: 1342 cm²/hen, 897 cm²/hen, 671 cm²/hen, 535 cm²/hen, and 445 cm²/hen. Egg production and physical egg quality were measured. Hen health and welfare parameters including corticosterone levels, H/L, oxidative stress pathways, jejunum tight junction protein expression, bone health, gut histology, body condition, and cytokine expression were evaluated. The results from this indicated that higher stocking densities resulted in lower production but larger eggs, while feed efficiency remained unaffected. Furthermore, physical egg quality parameters also remained unaffected. When stress and welfare parameters were analyzed, this research identified that decreasing stocking density did not affect jejunum oxidative stress pathways, pro-inflammatory cytokine expression, bone health, or intestinal health. At the final sampling period (69 weeks), the highest stocking density demonstrated higher corticosterone concentrations and IL-10 expression compared to the lowest stocking density. Furthermore, feather scores were found to be poorer as density increased. Finally, the highest density had higher Hansen’s test scores compared to other densities, which indicates a greater fear response. In conclusion, it appears that decreasing stocking density may provide some benefits in production and welfare to commercial egg layers, particularly at the end of the laying cycle. Full article

This study was conducted to evaluate the effects of feeding regimens and dietary methionine (Met) levels on the growth performance and feather growth of Cherry Valley ducks from 29 to 49 days of age. A 2 × 3 factorial arrangement was employed, consisting of two feeding regimens (ad libitum or “5+2” feed restriction: 5 days ad libitum + 2 days of fasting) and three levels of dietary Met (0.32%, 0.40%, or 0.48%). A total of 600 29-day-old male Cherry Valley ducks (initial body weight: 2.18 ± 0.12 kg) were randomly assigned to six treatment groups, with 10 replicates of 10 ducks each. Dietary Met as a main effect did not significantly influence growth performance (p > 0.05). The “5+2” feed restriction regimen reduced the 49-day final body weight, body weight gain, and feed intake (days 29–49) compared with ad libitum feeding, with a concurrent increase in the feed conversion ratio (p < 0.01). Body weight uniformity in the “5+2” feed restriction group was 4.33% higher than in the ad libitum group, though this difference was not statistically significant (p > 0.05). In addition, the feeding regimen tended to affect the feather weight and feather ratio, with the “5+2” regimen reducing the feather weight (p < 0.1) but increasing the feather ratio (p < 0.1) relative to ad libitum feeding. Higher dietary Met levels showed a tendency to improve the feather length and overall feather score (p < 0.1). A significant interaction was observed between the feeding regimen and Met level for wing feather length (p < 0.05). In conclusion, the “5+2” feed restriction impaired the growth performance and absolute feather yield in meat ducks. However, dietary Met levels interacted with feeding strategies to affect feather development. Specifically, under ad libitum feeding conditions, moderate-to-high Met supplementation (0.48% Met) appeared to be beneficial for feather yield, whereas lower Met levels (0.32% Met) were more effective for enhancing feather mass under restricted feeding. These findings highlight the potential to tailor Met supplementation according to feeding regimen to optimize both production and feather quality in ducks. Full article

Supercooled droplets that collide with the windward surface of the aircraft will freeze, which results in icing on both stationary and rotating components. The ice accretion on rotating surfaces is physically different from those on stationary components. The icing phenomenon on the surface of a rotating intake cone was investigated in an icing wind tunnel, and the influence of icing conditions of supercooled large droplets on the experimental results was analyzed. In the experiments, the ice accretion of the intake cone was studied under various conditions, including rotational speed, wind speed, icing temperature, droplet diameter, and icing time. The ice shape on the surface of the intake cone is notably unique due to the influence of centrifugal force, which produces a longer feather-like ice structure that has a significant effect on the performance of the engine. The process of ice shedding caused by centrifugal force is also critical for the engine anti-icing process. Therefore, it is essential to study the icing characteristics under rotational effects during the design and verification process of engine anti-icing systems. Full article

Geotextiles are widely used for separation, drainage, filtration, and erosion control, as well as for enhancing plant growth conditions. The objective of this study was to evaluate the impact of incorporating poultry feathers on the biodegradation rate of nonwoven geotextiles in arable soil. The research was conducted under laboratory conditions, with biodegradation assessed based on mass loss. The findings confirmed that the presence of keratin-rich waste positively influenced the biodegradation rate of the tested materials. Additionally, the potential ecotoxicological effects of biodegradation were examined, revealing no adverse impact on microbiological activity. Statistical analysis demonstrated a correlation between material composition and biodegradation time. This study represents a significant step toward the sustainable management of poultry feather waste in agricultural applications. The tested materials could serve as an environmentally viable alternative for long-term applications, aligning with ecological sustainability principles by simultaneously enriching soil with essential nutrients and promoting waste valorization. Full article

Secondary sexual traits, such as specific body parts or colouration, play an important role in mating interactions. It has been proposed that they function as quality indicators driven by sexual selection. In birds, much attention has been paid to the study of feather pigmentation, especially in diurnal passerines. However, recent research demonstrates that structural achromatic colours are likely to be of similar importance for communication, especially for species inhabiting poorly lit environments and that are active at night. Using 15 years of capture–recapture data from a long-term study on adult European Nightjars (Caprimulgus europaeus), we investigated the role of males’ white tail and wing markings as secondary sexual traits. We show that the inter-individual variation in marking size exceeds that of the other morphometric variables, suggesting that wing and tail markings could be subject to sexual selection. Older males, individuals with a higher body condition index, and long-term territory holders had larger markings, while these effects were particularly pronounced in terminal tail feather markings. The importance of markings for signalling is likely related to their observed use in social displays. Pronounced site differences in tail marking sizes and annual variation suggest environmental factors acting on the ornaments that remain to be further examined. 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

Ecotones, the transitional zones between distinct habitats, are vital for ecosystem functioning and habitat diversity. Traditional management practices frequently create abrupt boundaries, leading to stressful conditions for organisms. To address this challenge, an underutilized land management technique called “edge feathering”, which involves gradual thinning of the canopy along the forest edge, has been introduced. This study, conducted at Holden Arboretum in Kirtland, Ohio, investigated the effects of edge feathering on light availability and understory plant diversity in edge feathered and control treatments. We calculated the coefficient of variation in light availability as light heterogeneity and plant diversity indices at the plot level. Edge feathering increased light heterogeneity by more than 2.5-fold. It also significantly increased biodiversity, yielding twice the species richness and approximately 1.5 times higher Shannon and Simpson’s Diversity (1/D) indices compared to unmanaged control plots. Furthermore, greater light heterogeneity exhibited a strong positive correlation with increased understory plant diversity. These effects were observed within just 3.5 years of implementation, underscoring the rapid and measurable benefits of edge feathering for plant community diversity. Our results further suggest the hypothesis that light heterogeneity might be an important driver of small-scale plant community diversity in this system, which could be tested directly in the future. Full article

Zoos play dual roles in wildlife conservation and in providing recreational experiences for visitors in urban green spaces. However, the impacts of thermal environments on both visitor comfort and captive animal welfare remain unexplored, which is an important aspect to address for improving overall zoo management. This study investigated thermal conditions at Jinan Zoo, China, over 20 summer days. Questionnaires were used to collect visitor thermal comfort and viewing satisfaction, while the thermal mitigation behaviors of 70 blue peafowls were recorded under various thermal conditions on-site. The findings showed that the wet-bulb globe temperature (WBGT) neutral range for visitors was 20.1–24.4 °C, with a significant drop in visitor numbers when WBGT exceeded 35.5 °C. Visitors with higher animal viewing satisfaction (aVSV) scores were more heat tolerant. The blue peafowls reduced their activity levels and displayed feather-spreading and gular flutter at WBGT levels of 26.4–30.4 °C, especially during peak visitor hours. Our study also showed that visitor thermal sensation was most affected by radiation, whereas blue peafowl heat stress was likely influenced by air temperature, followed by humidity and radiation. These findings offer practical insights for designing zoo enclosures and visitor areas to improve comfort and animal welfare in hot weather. Full article

Feather pecking can influence the welfare and health concerns of all farmed poultry and affect production and economic aspects. Although some information is available about feather pecking behavior in chickens and ducks, the risk factors of feather pecking in goslings have not been fully demonstrated. In this study, 3-day-old Yangzhou goslings were chosen, and risk factors of feather pecking injurious behavior were investigated, including stocking density, rearing method, flock uniformity, and environmental enrichment. The gosling performed three different pecking behaviors in starter barns from 3d of age to 10d, including gentle feather pecking (GFP), severe feather pecking (SFP), and aggressive pecking (AGP), and the corresponding proportions were 82.16%, 17.02%, and 0.82%, respectively, with peak aggressive feather pecking at 4–5 days of age. The pecked gosling also led to further pecking by conspecifics. Goslings preferred to peck the back (77.32%) and head (11.14%), which caused skin damage to the epidermal and dermal layers, accompanied by a decrease in feather follicle number and diameter. In addition, the effect of the stocking density and population uniformity on the occurrence of feather pecking was determined. The higher feather pecking frequencies and poorer feather quality of goslings were observed under high-density conditions than those of lower-density environments. Importantly, the lower population uniformity resulted in more aggressive pecking, potentially linked to the establishment of a social hierarchy. Finally, environment-related changes in pecking behavior were investigated. The results showed that damp and dirty housing conditions deteriorated plumage conditions and the occurrence of feather pecking, and environment enrichment (the grass section) could significantly reduce the incidence of pecking. Taken together, lower stocking density, higher population uniformity, and the provision of enrichment can reduce the prevalence of feather pecking. Meanwhile, feather pecking in goslings, with the back being the most commonly targeted area, can lead to the loss of back feathers and even skin damage. These results help to develop effective management and prevention strategies to reduce the negative effects of pecking behavior on goose health and performance. Full article

Underground cold storage gives rise to special challenges that require innovative solutions to ensure maximum energy efficiency. Conventional energy systems tend to be based on high energy use, so sustainable solutions are crucial. This study explores the novel idea of biomimetics and how it might be used in the planning and building of underground cold storage facilities as well as other infrastructure projects. Biomimetic strategies, inspired by termite mounds, gentoo penguin feathers, and beehive structures, are applied to minimize reliance on energy-intensive cooling systems. These natural models offer efficient thermal regulation, airflow optimization, and passive cooling mechanisms such as geothermal energy harvesting. The integration of naturally driven convection and ventilation ensures stable internal temperatures under varying conditions. Biomimicry was employed in Revit Architecture, coupled with structural optimization, to eliminate urban space’s limitations and further increase energy efficiency. The analytical work for this paper utilized a set of formulas that represent heat flow, thermal resistance, R-value, thermal transmittance, U-value, solar absorption, and G-value. The results pointed to very good insulation, with exterior walls having an R-value of 10.2 m²K/W and U-value of 0.98 W/m²K. Among the chosen 3-layer ETFE cushion with a U-value of 1.96 W/m²K, with a G-value of 0.50, showed good heat regulation and daylight management. Furthermore, bagasse-cement composites with a very low thermal conductivity of 0.10–0.30 W/m·K provided good insulation. This research proposes a scalable and sustainable approach in the design of underground cold storage by merging modelling based on Revit with thermal simulations. Biomimicry has been demonstrated to have the potential for changing subterranean infrastructure, conserving energy consumption, and creating eco-friendly construction practices. Full article

Follicular cells represent a valuable resource for genetic research, biotechnology and cryopreservation in biobanks, particularly for the conservation of endangered species. They offer a more practical alternative to gametes, embryos and fibroblasts. Collection of these cells can be achieved through feather plucking. Feather samples were opened with a scalpel and the feather pulp was washed with PBS, cut into cubes and digested in collagenase type IV. Cultivation was carried out in DMEM culture medium with 15% fetal bovine serum, 1% penicillin/streptomycin and 0.5% amphotericin, under incubation conditions of 39.5 °C and 5% CO₂. Passages were carried out with 5% EDTA for 5 min. The culture was successful, with great cell proliferation, adherence to plastic and aggregation into cell colonies. This method was effective in obtaining feather follicle cells from wild birds, especially when collected up to 6 h after their death, and can serve as a base protocol for research with feather follicle cells aiming to create biobanks. Full article

Face detection in resource-constrained environments presents challenges, due to the computational demands of state-of-the-art models and the complexity of real-world conditions, such as variations in scale, pose, and occlusion. This study introduces FeatherFace, a lightweight face-detection architecture with only 0.49 M parameters, designed for high accuracy and efficiency in such environments. Leveraging MobileNet-0.25 as a backbone, FeatherFace incorporates advanced feature-integration strategies, including a bidirectional feature pyramid network (BiFPN), a convolutional block attention module (CBAM), deformable convolutions, and channel shuffling. Evaluated on the WIDERFace dataset, FeatherFace achieves an overall average precision (AP) of 87.2%, with notable performance gains of 4.0% AP on the Hard subset compared with the baseline. Ablation studies highlight the critical role of multiscale feature integration and the strategic placement of attention mechanisms in addressing detection challenges such as small or occluded faces. With its compact design and reduced inference time, FeatherFace bridges the gap between the reliability of computationally intensive models and the need for deploying robust models in highly resource-constrained environments, such as edge devices and embedded systems. This work provides valuable insights for developing robust and lightweight models suited to challenging real-world applications. Full article