Search Results (11)

Alternative housing systems for laying hens, such as the aviary, promote the expression of dustbathing behavior by providing substrate materials to improve their welfare. However, extensive litter areas in aviaries can lead to reduced air quality and increased incidence of diseases, making them unsuitable for deployment in new large cage aviary unit (LCAU) systems in China. Dust baths have advantages in terms of continuous availability, but their design lacks unified standards. This study explored the effects of different areas, shapes (circular and square), and substrate depths (1 cm, 5 cm, 9 cm) of dust baths on dustbathing behavior in LCAU systems by recording digital video. Each LCAU system was initially populated with 305 Jingfen No. 2 laying hens at 50 days of age. The dust baths were initially placed on the bottommost tier at 66 days of age. The results showed that after approximately 3 weeks of adaptation to dustbathing, the average daily proportion of dustbathing hens within the flock stabilized at approximately 10%. A 50 cm diameter circular dust bath could accommodate their dustbathing requirements. Increasing the number of circular dust baths to 2 did not significantly affect the daily proportion of dustbathing hens. Both the circular dust bath and a 5 cm depth substrate resulted in better expression of the hens’ side rubbing behavior and the lower frequency of tossing behavior. Full article

The aims of this study were to find suitable environmental enrichment (EE) and evaluate the combined effect of two EEs, variable light intensity (VL) lighting program and EH, on mental health and hepatic metabolic regulation in commercial broilers. To find the advantageous EEs for broilers, three different EEs (board, hut, and ramp) were tested in trial 1. EEs were placed and the engagement of birds to EEs, dustbathing behavior, and daily physical activity were observed. Birds treated with huts showed higher engagement than the board- or ramp-treated birds (p < 0.05). The results of dustbathing behavior and daily physical activity indicated that the environmental hut (EH) is the most favorable enrichment for broilers. In the second trial, to test the effect of EHs on mental health and hepatic metabolic conditions, the brain and liver were sampled from the four treatment birds (20 lx_Con, 20 lx_Hut, VL_Con and VL_Hut) on day 42. The lower expression of TPH2 (tryptophan hydroxylase 2) of VL_Hut birds than those of VL_Con and 20 lx_Hut treated birds suggests the combining effect of EHs with the VL lighting program on the central serotonergic homeostasis of broilers. Reduced expressions of TH (tyrosine hydroxylase), GR (glucocorticoid receptor), BDNF (brain-derived neurotrophic factor) of VL_Hut treated birds compared to those of VL_Con and 20 lx_Hut birds suggest lower stress, stress susceptibility, and chronic social stress in VL_Hut treated birds. The expression of CPT1A (carnitine palmitoyl transferase 1) increased over three-fold in the liver of VL_Con birds compared to 20 lx_Con birds (p < 0.05). EHs treatment in VL birds (VL_Hut) significantly decreased CPT1A but not in 20 lx birds (20 lx_Hut). The expression of ACCα (acetyl-CoA carboxylase alpha) was significantly decreased in VL_Con birds compared to 20 lx_Con birds. There was no significant difference in the hepatic FBPase (fructose-1,6-bisphosphatase), GR, and 11β-HSD1 (11 β-hydroxysteroid dehydrogenease-1) expression between 20 lx_Con and VL_Con birds, but EHs significantly stimulated GR in 20 lx_Hut birds, and stimulated FBPase and 11β-HSD1 expression in the VL_Hut birds compared to 20 lx_Con birds, suggesting that the VL lighting program reduced fatty acid synthesis and increased fatty acid β-oxidation in the broilers’ liver and VL_Hut improved the hepatic de novo glucose production. Taken together, the results suggest that the stimulated voluntary activity by EHs in the light-enriched broiler house improved mental health and hepatic metabolic function of broilers and may indicate that the improved hepatic metabolic function contributes to efficient nutritional support for broilers. Full article

Cage-free (CF) layer houses tend to have high particulate matter (PM) levels because of bedding/litter floor and the birds’ activities, such as perching, dustbathing, and foraging on it. It has been reported that optimizing bedding management can potentially suppress PM levels in CF houses. The objectives of this study were to (1) test the effect of the top application of new bedding materials (BMs) on PM levels and (2) compare different BM PM reduction efficiencies. Small flake shavings (SFS), large flake shavings (LFS), and aspen wood chips (AWC) were top-dressed on the surface of the original litter (33-week-old litter) evenly in each of the BM treatment rooms at 20% volume of the original litter floor. The initial litter depths in the control, SFS, LFS, and AWC rooms were 4.6 ± 0.6, 4.8 ± 0.8 cm, 4.8 ± 0.8 cm, and 4.6 ± 0.9 cm, respectively. One room was used as a control without adding new BM. The results indicate that the top application of new bedding suppressed PM levels in all treatment rooms (p < 0.01). The PM_2.5 reductions in the SFS, AWC, and LFS treatment rooms were 36.5%, 34.6%, and 28.9% greater than in the control room, respectively. The mitigation efficiencies were different between PM sizes. For instance, PM_2.5, PM₁₀, and TSP in the SFS room were lower than in the control room by 36.5%, 39.4%, and 38.7%, respectively. For litter quality, the moisture content was 18.0 ± 2.8, 20.0 ± 3.1, 20.6 ± 2.4, and 19.7 ± 4.2% in the control, SFS, LFS, and AWC rooms, respectively. Treatment rooms with 20% new BM had 10% higher litter moisture than the control room. The findings of this study reveal that the top application of new bedding on old litter is a potential strategy for reducing PM generation in CF houses. Further studies are warranted, such as regarding the effect of different ratios of new bedding on PM reduction, cost analysis, and verification tests in commercial CF houses. Full article

Animal welfare is a key and distinct component of sustainable agriculture and food security. People, both as citizens and consumers, have become more concerned about the husbandry of livestock species. Positive welfare goes a step further than the common welfare approach, supporting that a good life for animals is not only the alleviation of negative aspects, but also the promotion of positive affectivities. So, a sustainable management system for any livestock species should promote positive aspects in the lives of animals. Poultry is one of the species whose welfare is most impaired, and numerous concerns are raised by society. For all the above, we reviewed the positive welfare indicators that have been studied in livestock poultry and that can be used to promote positive effects and assess welfare for the most common species, i.e., broilers, laying hens, turkeys, ducks, geese, quails and ostriches. We analyzed the results categorized by species, discussed the connection of the indicators with sustainable management, and made proposals for future studies. Exploration and dustbathing have been extensively studied and seem most promising, especially in broilers and laying hens, followed by nesting and perching, and swimming for waterfowl. Qualitative behavioral assessment (QBA) is already applied in protocols for broilers and laying hens, but the results are not as promising due to the homogeneity of the flock and the difficulty in observations. Play has been studied mostly in broilers but is a behavior difficult to recognize and needs further understanding. The results are limited for all species, except broilers and laying hens. Full article

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD) or low (LD) density. Through focal-animal sampling, the frequency and duration of behaviors were recorded continuously for 5 min at two timepoints for one day in weeks 2, 4, and 7. Birds were active for 30% of the observed time, with birds showing more activity in HC compared with LC. Birds in HC pens spent more time preening and foraging than birds in LC pens, which was interpreted as a positive outcome. Dustbathing and play were not impacted by complexity, possibly due to the observation method. Birds were more frequently active at HD compared with LD, but did not spend more time being active, suggesting disturbances. Birds foraged, drank, and ate less frequently in HD compared with LD, presumably because birds had more difficulty accessing resources. Activity and active behaviors reduced as birds aged, while preening frequency increased, possibly due to frustration, but this was not confirmed. Perching was unaffected by age, showing a persistent motivation to perform the behavior. Our results indicate that a complex environment provides positive stimulation for foraging, locomotion, preening, and overall activity. Despite reduced activity, many benefits of the tested environmental complexity and low density persisted as birds aged. Full article

Image analysis using machine learning (ML) algorithms could provide a measure of animal welfare by measuring comfort behaviours and undesired behaviours. Using a PLF technique based on images, the present study aimed to test a machine learning tool for measuring the number of hens on the ground and identifying the number of dust-bathing hens in an experimental aviary. In addition, two YOLO (You Only Look Once) models were compared. YOLOv4-tiny needed about 4.26 h to train for 6000 epochs, compared to about 23.2 h for the full models of YOLOv4. In validation, the performance of the two models in terms of precision, recall, harmonic mean of precision and recall, and mean average precision (mAP) did not differ, while the value of frame per second was lower in YOLOv4 compared to the tiny version (31.35 vs. 208.5). The mAP stands at about 94% for the classification of hens on the floor, while the classification of dust-bathing hens was poor (28.2% in the YOLOv4-tiny compared to 31.6% in YOLOv4). In conclusion, ML successfully identified laying hens on the floor, whereas other PLF tools must be tested for the classification of dust-bathing hens. Full article

The welfare of laying hens in cage systems is of increasing concern. Represented by the European Union’s ‘End the Cage Age’ initiative, more and more countries have advocated cage-free farming. China, an important country for poultry farming and consumption in the world, is highly dependent on cage systems and lacks confidence in alternative (e.g., free-range) systems. In this context, using China’s abundant woodland resources (including natural forests, plantations, and commercial forests) to facilitate the management of laying hens in a free-range environment may provide highly promising welfare improvement programs. On the basis of the Five Freedoms, we assess the welfare status of understory laying hen management systems with reference to the behavioural needs and preferences of laying hens and the EU standards for free-range and organic production (highest animal welfare standards in the world). The results show that the considered systems meet or even exceed these standards, in terms of key indicators such as outdoor and indoor stocking density, outdoor activity time, and food and drug use. Specifically, the systems provide sufficient organic food for laying hens without using antibiotics. They allow laying hens to avoid beak trimming, as well as to express nesting, foraging, perching, reproductive, dustbathing and other priority behaviours. The presence of roosters and higher use of woodland space allow the laying hens to achieve better feather and bone conditions, thus reducing stress and fear damage. Notably, the predation problem is not yet considered significant. Second, there is evidence that understory laying hen systems are profitable and have been welcomed and supported by farmers and governments in the southwest, south, and north of China. However, whether it can be scaled up is uncertain, and further research is needed. In addition, laying hens in this management system face various risks, such as foot injury, parasitism, and high dependence on consumer markets, which must be considered. Overall, agro-forestry, or accurately, understory poultry raising, provides opportunities and possibilities for free-range laying hens and welfare improvement in China and other countries. Full article

Laying hens in the UK and EU must be provided with litter for pecking and scratching. In enriched cages, this is commonly provided by dispensing layer’s feed onto a scratch mat. Mats vary in design and size, which might affect hen behaviour and egg quality, since eggs are sometimes laid at the mats. We investigated if four different scratch mats (BD, K, V, Z) provided to hens in enriched cages resulted in differences in behaviour on the mats and external egg quality. Twenty-four 60-bird cages (6 cages/bank × 4 banks) with 2 mats/cage at one tier of a commercial enriched cage unit were used. Mats were allocated to cages in a balanced design prior to the flock arriving. Hens and eggs were studied at 30, 50 and 79 weeks of age, with three behaviour observations (before, during or after scratch feed application). The data were analysed by GLMMs or LMMs. The vast proportions of birds on the mats were standing (0.720) or sitting (0.250). Bird proportions on the mats were low overall and declined from 0.028 (30 weeks) and 0.030 (50 weeks) to 0.020 (79 weeks) (p < 0.001). The greatest proportion of hens were observed on Z (p < 0.001), which had the largest area, but relative to the available area least birds were on Z and most were on K (p < 0.001). Foraging was not affected by bird age or mat type but was greater at the second observation (p < 0.001). Most eggs were laid in the nest box and were clean. Clean eggs declined, and dirty eggs increased, significantly with age, particularly at the scratch mat (p < 0.001). Dirty eggs were not affected by mat design. Cracked eggs were highest at 79 weeks of age, particularly with BD mats (p < 0.001). Overall, scratch mat designs had minimal effects on behaviour (but few hens were seen there) and egg quality. Full article

Audio data collected in commercial broiler houses are mixed sounds of different sources that contain useful information regarding bird health condition, bird behavior, and equipment operation. However, characterizations of the sounds of different sources in commercial broiler houses have not been well established. The objective of this study was, therefore, to determine the frequency ranges of six common sounds, including bird vocalization, fan, feed system, heater, wing flapping, and dustbathing, at bird ages of week 1 to 8 in a commercial Ross 708 broiler house. In addition, the frequencies of flapping (in wing flapping events, flaps/s) and scratching (during dustbathing, scratches/s) behaviors were examined through sound analysis. A microphone was installed in the middle of broiler house at the height of 40 cm above the back of birds to record audio data at a sampling frequency of 44,100 Hz. A top-view camera was installed to continuously monitor bird activities. Total of 85 min audio data were manually labeled and fed to MATLAB for analysis. The audio data were decomposed using Maximum Overlap Discrete Wavelet Transform (MODWT). Decompositions of the six concerned sound sources were then transformed with the Fast Fourier Transform (FFT) method to generate the single-sided amplitude spectrums. By fitting the amplitude spectrum of each sound source into a Gaussian regression model, its frequency range was determined as the span of the three standard deviations (99% CI) away from the mean. The behavioral frequencies were determined by examining the spectrograms of wing flapping and dustbathing sounds. They were calculated by dividing the number of movements by the time duration of complete behavioral events. The frequency ranges of bird vocalization changed from 2481 ± 191–4409 ± 136 Hz to 1058 ± 123–2501 ± 88 Hz as birds grew. For the sound of fan, the frequency range increased from 129 ± 36–1141 ± 50 Hz to 454 ± 86–1449 ± 75 Hz over the flock. The sound frequencies of feed system, heater, wing flapping and dustbathing varied from 0 Hz to over 18,000 Hz. The behavioral frequencies of wing flapping were continuously decreased from week 3 (17 ± 4 flaps/s) to week 8 (10 ± 1 flaps/s). For dustbathing, the behavioral frequencies decreased from 16 ± 2 scratches/s in week 3 to 11 ± 1 scratches/s in week 6. In conclusion, characterizing sounds of different sound sources in commercial broiler houses provides useful information for further advanced acoustic analysis that may assist farm management in continuous monitoring of animal health and behavior. It should be noted that this study was conducted with one flock in a commercial house. The generalization of the results remains to be explored. Full article

This study investigated the welfare of laying hens in different non-caged housing systems, namely a deep-litter barn system (BS), a free-range system (FRS) and an organic system (OS). The study was conducted on 270 hens of a native breed Green-legged Partridge (Z-11) and 270 Hy-Line Brown hybrids. Visual scans were performed to record behaviour of hens. Hens were housed in groups of 30 and observed over the course of one day at 20, 36 and 56 weeks of age. Dustbathing, scratching, wing stretching, wing flapping and preening were recorded as comfort behaviours. Pecking, fighting, threatening and chasing were recorded as agonistic behaviours. The percentage of run use was higher in native hens than in commercial hens (p < 0.05). The proportion of hens exhibiting comfort behaviours housed in the FRS and OS was similar but over twice as high as in the BS (p < 0.05). In the FRS and OS, the percentage of hens displaying comfort behaviours increased with age (p < 0.05). In all the production systems, the percentage of birds displaying comfort behaviours was higher in native breed hens than in commercial breeds (p < 0.05). In the BS, the higher proportion of hens displaying an agonistic behaviour was seen more in commercial breed than in the native breed hens (p < 0.05). The percentage of birds displaying an agonistic behaviour declined with hen age, both in commercial and native breed hens. Full article

In most areas of the world, broiler chickens are raised in floor systems, but cage confinement is becoming more common. The welfare of broiler chickens in cages is affected by movement restriction, poor bone strength due to lack of exercise, and prevention of key behavioral patterns such as dustbathing and ground scratching. Cages for broiler chickens also have a long history of causing skin and leg conditions that could further compromise welfare, but a lack of controlled studies makes it difficult to draw conclusions about newer cage designs. Cage environments are usually stocked at a higher density than open floor systems, and the limited studies available suggest that caging may lead to increased levels of fear and stress in the birds. Further, birds reared on the floor appear less likely to harbor and shed Salmonella, as litter may serve as a seeding agent for competitive exclusion by other microorganisms. Cages for laying hens used in egg production have met with substantial opposition due to welfare concerns and caging broiler chickens will likely be subject to the same kinds of social disapproval. Full article