Search Results (185)

In intensive broiler production, rapid environmental fluctuations can induce heat stress, adversely affecting flock welfare and productivity. Apparent temperature (AT), integrating temperature, humidity, and wind speed, provides a comprehensive thermal index, guiding predictive climate control. This study develops a multi-step AT forecasting model based on a hybrid SE-TCN–Transformer architecture enhanced with Kalman filtering. The temporal convolutional network with SE attention extracts short-term local trends, the Transformer captures long-range dependencies, and Kalman smoothing reduces prediction noise, collectively improving robustness and accuracy. The model was trained on multi-source time-series data from a commercial broiler house and evaluated for 5, 15, and 30 min horizons against LSTM, GRU, Autoformer, and Informer benchmarks. Results indicate that the proposed model achieves substantially lower prediction errors and higher determination coefficients. By combining multi-variable feature integration, local–global temporal modeling, and dynamic smoothing, the model offers a precise and reliable tool for intelligent ventilation control and heat stress management. These findings provide both scientific insight into multi-step thermal environment prediction and practical guidance for optimizing broiler welfare and production performance. Full article

Fowl adenovirus (FAdV) can cause different poultry diseases with economic losses in the broilers and layers commercial farms. FAdV is currently classified into five species and 12 serotypes, disseminated in poultry flocks worldwide. The present study aimed to identify FAdV species and serotypes in Brazilian poultry farms. A total of 678 chicken flocks from the main Brazilian poultry-producing regions were evaluated for FAdV infection between 2020 and 2023. FAdV was detected by a real-time PCR targeting 52K gene and further genotyped by partial sequencing of the hexon gene followed by phylogenetic analyses. The results demonstrated that FAdV was detected in 72 flocks (10.6%). In 46 of these samples, FAdV species and serotypes could be identified, including three main species: Aviadenovirus ventriculi (FAdV-A = 15), Aviadenovirus gallinae (FAdV-D = 15) and Aviadenovirus hepatitidis (FAdV-E = 16). Phylogenetic analysis based on 173 partial hexon sequences (including sequences from this study, 44 previously sequenced in Brazil, and 86 data from other countries) revealed five separate clades for FAdV species. All Brazilian FAdVs were classified into the same three species reported above (FAdV-A = 19, FAdV-D = 34, FAdV-E = 37), and also in well-supported subclades for each serotype: FAdV-A1 (n = 19), FAdV-D9 (n = 1), FAdV-D11 (n = 33), FAdV-E6 (n = 1), FAdV-E8a (n = 33), FAdV-E8b (n = 3). Amino acid substitutions in the hyper variable regions (1, 2 and 3) and conserved motifs of the Hexon protein were further analyzed, enabling discrimination between closely related serotypes. This study demonstrates the circulation of different FAdVs in Brazil, highlighting FAdV-A1, FAdV-D9, FAdV-D11, FAdV-E6, FAdV-E8a and FAdV-E8b. The findings reported here also indicate genetic and amino acid diversity in the Hexon protein of the FAdVs in Brazilian poultry farms, which are of importance for molecular surveillance and poultry diseases control strategies. Full article

Enterococci, commonly found in the normal intestinal flora of humans and animals, have emerged as an important human pathogen. A total of 184 isolates (88 isolates in 2015 and 96 isolates in 2016) were collected from 46 flocks. Two predominant enterococcus species were identified: Enterococcus faecalis (59%) and Enterococcus faecium (~39%). Resistance to penicillin was significantly decreased in the overall enterococci community, while it remained unchanged in the multi-class drug resistant (MDR) community. We identified the emeA and efrAB genes, which encode efflux pump systems, in 93% (26/28) of the MDR isolates with (intermediate) resistance to levofloxacin. The ermB gene was present in all MDR strains with resistance to erythromycin. The lsa gene was detected in 87% (84/97) of the MDR isolates with resistance to quinupristin/dalfopristin. About 82.2% of MDR strains in 2015 and 100% of MDR strains in 2016 carried the insertion sequence IS256, which is known to be associated with AMR genes, conferring resistance to erythromycin, gentamicin and vancomycin in enterococci. These results support the need for monitoring AMR in Gram-positive bacteria in poultry production, specifically in broiler chicken farms, to complement current AMR data, and develop a timely intervention framework. Full article

It is estimated that global meat production will show an upward trend, with the most dynamic growth projected in the poultry sector (it is estimated that poultry meat consumption will be 2.3 times higher by 2050 than in 2010). The expected increase in consumption of poultry meat, mainly from intensively reared broiler chickens, is associated with an increasing prevalence of diseases, particularly those affecting the digestive system. One important parasitic disease is coccidiosis, a gastrointestinal disease caused by widespread protozoa of the genus Eimeria. The occurrence of coccidiosis in broiler chicken flocks results in a significant deterioration of production rates. Coccidiostats are most commonly used in the prevention of this disease, which are introduced in rotation into the feed ration. However, long-term use of coccidiostats is associated with the risk of parasite resistance development and the possibility of residues in animal products. Therefore, there is a need to search for safe and effective alternatives to pharmacological coccidiostatic agents. This review aims to analyze the available literature data on the efficacy of vaccines and functional feed supplements, such as plant substances, probiotics, prebiotics, and organic acids, in the prevention of coccidiosis. Full article

Understanding how environmental conditions affect broiler comfort across different seasons is crucial for enhancing welfare in commercial poultry production. This study aimed to identify the relationship between housing environment, litter conditions, and broiler discomfort at different growth stages using data collected from two flocks reared during winter and summer. Environmental variables (temperature, humidity, ammonia, pH, and CO₂) and broiler responses were recorded and analyzed weekly. Discomfort was defined as a binary variable based on threshold deviations in temperature and air quality. Non-parametric statistical tests and a Random Forest model were employed to explore associations and predict comfort status. Results showed that discomfort was significantly higher during winter, particularly in weeks 1 and 6, likely due to thermal instability and rising ammonia levels. Summer flocks exhibited more stable comfort profiles. The predictive model achieved a high test accuracy (97.1%) and identified broiler weight, ammonia, and temperature as the strongest predictors of discomfort. Weekly discomfort patterns and feature importance analyses revealed critical intervention points and variables. These findings provide actionable insights for automating welfare monitoring in commercial broiler production, offering valuable information for season-specific management strategies and demonstrating the potential for integrating predictive models into automated welfare monitoring systems to support precision livestock farming. Full article

Campylobacter is the most common cause of bacterial foodborne illness in the EU, primarily linked to poultry. To better understand its transmission dynamics, we applied whole-genome sequencing (WGS) to Campylobacter isolates collected at slaughterhouses over a two-year period from broilers originating from 26 Danish farms. The samples included cloacal swabs and boot sock samples from broiler houses and surrounding farm environments. We identified 150 distinct cgMLST types among 883 isolates. While most cgMLST types were flock-specific, some persisted across production cycles or appeared at different farms, indicating entrenched contamination or potential common-source introductions. Notably, 39% of broiler-associated cgMLST types overlapped with human clinical isolates from the same period, with the strongest overlap among persistent and cross-farm types, particularly in conventional production systems. Our findings underscore the need for strengthened biosecurity, targeted surveillance of high-risk genotypes, and real-time WGS integration to mitigate the burden of human Campylobacteriosis. This study supports a One Health approach to managing zoonotic risk in poultry production. Full article

This review explores sexual aggression in broiler breeder males, aiming to synthesize existing scientific evidence regarding its causes, behavioral manifestations, and consequences, while addressing the genetic, neuroendocrine, and environmental mechanisms involved. Through an extensive analysis of scientific literature, the paper highlights that intensive genetic selection aimed at enhancing growth and productivity has resulted in unintended behavioral dysfunctions. These include the reduction or absence of courtship behavior, the occurrence of forced copulations, and a notable increase in injury rates among hens. Reproductive challenges observed in meat-type breeder flocks, in contrast to those in layer lines, appear to stem from selection practices that have overlooked traits related to mating behavior. Environmental and managerial conditions, including photoperiod manipulation, stocking density, nutritional imbalances, and the use of mixed-sex rearing systems, are also identified as contributing factors to the expression of sexual aggression. Furthermore, recent genetic findings indicate a potential link between inherited neurobehavioral factors and aggressive behavior, with the SORCS2 gene emerging as a relevant candidate. Based on these insights, the review emphasizes the importance of considering behavioral parameters in breeding programs in order to reconcile productivity objectives with animal welfare standards. Future research may benefit from a more integrative approach that combines behavioral, physiological, and genomic data to better understand and address the multifactorial nature of sexual aggression in poultry systems. Full article

Background/Objectives: Campylobacteriosis in human populations is an ongoing issue in both developed and developing countries. Poultry production is recognized as a reservoir for antimicrobial resistance and main source of human Campylobacter infection. Methods: In this study, sixty-five Campylobacter isolates were cultured from fecal samples collected from 17 flocks of broiler chickens in Alberta, Canada over two years (2015–2016). Susceptibility assays and PCR assays were performed to characterize resistance phenotypes and resistance genes. Conjugation assays were used to examine the mobility of AMR phenotypes. Results: Campylobacter jejuni was the predominant species recovered during both years of sampling. There were no Campylobacter coli isolates found in 2015; however, approximately 33% (8/24) of isolates collected in 2016 were Campylobacter coli. The two most frequent antimicrobial resistance patterns in C. jejuni collected in 2015 were tetracycline (39%) and azithromycin/clindamycin/erythromycin/telithromycin resistance (29%). One isolate collected in 2015 has resistance pattern ciprofloxacin/nalidixic acid/tetracycline. The tetO gene was detected in all tetracycline resistant isolates from 2015. The cmeB gene was detected in all species isolates with resistance to azithromycin/clindamycin/erythromycin/telithromycin, and from two isolates with tetracycline resistance. Alignment of the nucleotide sequences of the cmeB gene from C. jejuni isolates with different resistance patterns revealed several single nucleotide polymorphisms. A variety of multi-drug resistance patterns were observed through conjugation experiments. Conclusions: These data suggest that poultry production may serve as a potential reservoir for and source of transmission of multi-drug resistant Campylobacter jejuni and supports the need for continued surveillance. Full article

Environmentally modified housing [EMH; windowless, insulated sidewalls and ceiling, thermostatically controlled ventilation fans) versus conventional housing [CVH; cross-ventilated, insulated ceiling, ceiling fans) improved broiler performance in the summer. The objective of this investigation was to determine whether social behaviors differed between two population densities (0.06 m²/chick [HD] or 0.07 m²/chick [LD]) in these houses. We used a randomized block statistical design, involving houses, population densities, observation times, and bird age. Behaviors were observed weekly, during the morning and the afternoon. Individual observers focused on the group of broilers in one of three defined 26.76 m² areas in each of the four pens in each house. Aggressive encounters, tail and back pecking, feather eating, thermoregulatory, preening, and flock mobility were recorded. Feather pecking, eating and aggressive encounters were expressed at greater rates in HD birds in CVH. A salt-deficient diet caused increased feather pecking and aggressive encounters, which decreased after correction of the mistake. Increased heat indices (HIs), HD, and greater light intensity in CVH influenced behaviors and mortality more severely than in EMH. In CVH and EMH, burrowing/thermoregulatory/resting activity increased with increasing HIs. Afternoon preening was elevated significantly in EMH. It was concluded that broilers reared in EMH were more comfortable and experienced improved welfare compared to those reared in CVH. Full article

Infectious bronchitis virus (IBV) and low-pathogenic avian influenza virus (LPAIV) H9N2 are commonly identified in poultry, individually or in association with other pathogens. This study monitored 183 broiler farms affected by respiratory diseases across seven regions of Morocco from January 2021 to December 2023. Among these farms, 87.98% were vaccinated against IBV, while 57.92% were against AI H9N2. Abnormally high mortality rates were observed in 44.26% of the farms, with 24.69% of cases attributed to IBV, 50.62% to LPAI H9N2, and 13.58% due to coinfection with both IBV and H9N2. RT-PCR analysis of tissue samples and cloacal and tracheal swabs collected from 183 broiler farms revealed that 33.33% were positive for IBV and 34.97% for H9N2. Coinfection by IBV and H9N2 was detected in 12.57% of cases, peaking at 17% in 2022. Co-infected flocks exhibited severe clinical signs and lesions, such as reduced food consumption, diarrhea, and renal issues. The predominant lesions were in the respiratory tract, affecting 91.26% of infected broilers. Additionally, among the 183 flocks, 50 farms that tested positive for IBV infection were randomly selected from the seven regions of Morocco for further investigation of other respiratory pathogens, including Mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS), and infectious laryngotracheitis (ILT), using real-time RT-PCR. Detection rates for these pathogens were 26% for MG, 30% for MS, 4% for ILTv (vaccine strain), and 18% for ILTw (wild strain). Detection rates for single, dual, triple, and quadruple infections were 34%, 42%, 18%, and 4%, respectively. The most common dual and triple coinfections were IBV + H9N2 (14%) and IBV + MG + MS (10%). Phylogenetic analysis of the S gene identified two main IBV genotypes, namely, 793B and D181, with the latter being a strain circulating for the first time in Moroccan poultry. This underscores the urgent need to establish surveillance systems to track pathogen circulation and implement strategies to control virus spread, ensuring the protection of animals and public health. Full article

Measuring the weight of broilers is one of the most important yet labor-intensive metrics to monitor throughout a flock’s development. This study aimed to comparatively assess two broiler weighing systems in a commercial production system: an automatic weighing system using a suspended platform, and a manual weighing system. Six flocks, comprising 25,000 birds each, were monitored weekly, and the weight results obtained by manual and automatic methods were compared. Up to the third week of this study, the birds were restricted to the central region of the shed, where the broiler coop was located. From the fourth week onwards, the birds were distributed into four sectors within the shed, divided by fences. Differences in weight were found between the regions of the sheds for the automatic weighing, which demonstrates that the use of an automatic scale for each division is necessary. For the manual weighing, the differences were only found in the last week of rearing, suggesting that throughout the cycle, the weighings could be performed in a single quadrant, representing the shed. Regarding the weighing method, there were statistical differences between manual and automatic weighing. The average values for automatic weighing were 1% lower than the average values for manual weighing. However, from a commercial point of view, this small difference between the methods does not impact the poultry industry. The rational use of automatic scales is recommended to optimize the monitoring of broiler chicken performance, reduce excessive handling and, consequently, minimize animal stress, promoting greater well-being. Full article

Rearing broiler chickens generates large quantities of waste material in the form of bedding. Anaerobic digestion (AD) is a technology that can be applied to this waste. This study aimed to evaluate the AD of broiler litter, either screened (S) or unscreened (US), from different flocks, collected from each production batch, totaling nine, from a commercial farm. Anaerobic digestion was conducted in batch biodigesters, and fraction separation was performed through screening prior to loading. The S substrate from the second and fifth flocks did not produce biogas. Reductions in total (TS) and volatile solids were highest for S substrates from the third flock (50.5% and 58.3%, respectively). Only the third flock’s S substrates showed greater reductions in solids than the US substrates. Potential biogas and methane production were also highest in the third flock’s bedding for both the S substrate (336.8 and 218.2 L/kg of TS, respectively) and the US substrate (296.8 and 213.4 L/kg of TS, respectively). The methane concentration in the S substrate was highest in the third flock (64.8%), while in the US substrate, it was highest in the third and fourth flocks (70.3%). Screening the litter reduced the process efficiency. We conclude that fraction separation is inadvisable for broiler litter. Full article

This study reports an outbreak of hepatitis-splenomegaly syndrome (HSS) in a color broiler parent stock flock in Bangladesh, marking the first known instance of HSS associated with avian hepatitis E virus (aHEV) genotype 7 outside Europe and only the second report of HSS in South Asia. The affected flock exhibited severe clinical signs, including a high cumulative mortality, reaching 31.6% in hens, and an abrupt decrease in egg production, dropping by over 20 percent. Histopathological analysis of liver and spleen samples revealed multifocal areas of necrosis, hemorrhages, and bacterial colonies. RT-PCR confirmed the presence of aHEV and immunohistochemistry showed signals within hepatic sinusoids and peri-ellipsoidal zones in the spleen. Complete genome sequencing of RNA from liver and bile samples on the Illumina platform established a pathogenic link to aHEV genotype 7. Despite aHEV’s known association with HSS, inconsistencies in disease manifestation suggest additional cofactors influencing pathogenesis, with secondary bacterial infections potentially contributing to clinical severity in this outbreak. Overall, this case expands the geographic distribution of aHEV genotype 7 and highlights the need for further epidemiological studies to investigate genotype–pathogenicity associations, especially in regions with limited prior data on HSS. Full article

Detecting the daily behavior of broiler chickens allows early detection of irregular activity patterns and, thus, problems in the flock. In an attempt to resolve the problems of the slow detection speed, low accuracy, and poor generalization ability of traditional detection models in the actual breeding environment, we propose a chicken behavior detection method called FCBD-DETR (Faster Chicken Behavior Detection Transformer). The FasterNet network based on partial convolution (PConv) was used to replace the Resnet18 backbone network to reduce the computational complexity of the model and to improve the speed of model detection. In addition, we propose a new cross-scale feature fusion network to optimize the neck network of the original model. These improvements led to a 78% decrease in the number of parameters and a 68% decrease in GFLOPs. The experimental results show that the proposed model is superior to the traditional network in the speed, accuracy and generalization ability of broiler behavior detection. (1) The detection speed is improved from 49.5 frames per second to 68.5 frames per second, which is 22.6 frames and 10.9 frames higher than Yolov7 and Yolov8, respectively. (2) mAP0.5 reaches 99.4%, and MAP0.5:0.95 increases from 84.9 to 88.4%. (3) Combined with the multi-target tracking algorithm, the chicken flock counting, behavior recognition, and individual tracking tasks are successfully realized. Full article

Infectious bronchitis virus (IBV) poses a significant threat to poultry worldwide, necessitating robust surveillance and vaccination strategies. This study aimed to conduct IBV surveillance in Brazil, assess potential vaccine viral escapes, and evaluate vaccine persistence in vaccinated broilers. A total of 1000 tracheal swabs from 100 flocks across six states were analyzed using RT-PCR. The results showed that 91% of the flocks tested positive for IBV. The detected strains included GI-1, GI-11, and GI-23. Notably, 90% of batches received vaccines containing either GI-1 or GI-11 lineages. The study revealed vaccine persistence in 67 samples between days 16 and 32 post-vaccination. In contrast, unvaccinated batches had a high prevalence of IBV GI-11 strains (70%). These findings highlight widespread IBV circulation in Brazil with persistent viral presence in vaccinated birds and wild viruses in unvaccinated ones. Collectively, the data reveal a widespread presence of IBV in Brazil, characterized by prolonged viral persistence in vaccinated animals and the occurrence of wild viruses in both unvaccinated birds and those vaccinated against specific strains. It can be concluded from this study that there was a widespread occurrence of IBV in Brazil, providing long viral persistence in vaccinated animals, as well as the occurrence of wild virus in unvaccinated birds or birds vaccinated against individual strains. Full article