ReviewAnimals : an open access journal from MDPI2015
Air Quality in Alternative Housing Systems may have an Impact on Laying Hen Welfare. Part II-Ammonia.
Review in Animals : an open access journal from MDPI, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 42 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
42 citing papers in PubMed, 132 citations in OpenAlex.
- Daily behavioral patterns of laying hens kept in a multi-tier system across different microclimatic conditions.Veterinary and animal science · 2026Article
- Respiratory and Gastrointestinal Microbiome Shifts in Livestock Exposed to High-Ammonia Environments: A Systematic Review.Veterinary sciences · 2026Review
- Multiomics Integration Reveals Rearing System-Induced Variations in Volatile Organic Compounds, Metabolites, and Meat Quality of Lueyang Black-Bone Chickens.Journal of agricultural and food chemistry · 2025Article
- Doping of PDMS-NQS Sensors to Modify Their Response and Sustainability: Ammonia Quantitation in Farm Atmospheres as a Case Study.Polymers · 2025Article
- A smart automatic control and monitoring system for environmental control in poultry houses integrated with earlier warning system.Scientific reports · 2025Article
- Physiological Responses of Laying Hens to Chronic Cold Stress and Ammonia Exposure: Implications for Environmental Management and Poultry Welfare.Animals : an open access journal from MDPI · 2025Article
- Co-expression of LncRNA and mRNA in the cumulus-oocyte complex of rabbits exposed to ammonia.BMC veterinary research · 2025Article
- Environmental Gradients and Hen Spatial Distribution in a Cage-Free Aviary System: Internet of Things-Based Real-Time Monitoring for Proactive Management.Animals : an open access journal from MDPI · 2025Article
- Modeling and Regulation of Dynamic Temperature for Layer Houses Under Combined Positive- and Negative-Pressure Ventilation.Animals : an open access journal from MDPI · 2024Article
- Chinese Herbal Extracts Mitigate Ammonia Generation in the Cecum of Laying Hens: An In Vitro Study.Animals : an open access journal from MDPI · 2023Article
- Article
- Practical Preventive Considerations for Reducing the Public Health Burden of Poultry-Related Salmonellosis.International journal of environmental research and public health · 2023Review
- Measurement of Ammonia and Hydrogen Sulfide Emission from Three Typical Dairy Barns and Estimation of Total Ammonia Emission for the Chinese Dairy Industry.Animals : an open access journal from MDPI · 2023Article
- When Everything Becomes Bigger: Big Data for Big Poultry Production.Animals : an open access journal from MDPI · 2023Review
- Effects of theAnimals : an open access journal from MDPI · 2023Article
- Internet of Things-based sustainable environment management for large indoor facilities.PeerJ. Computer science · 2023Article
- Bacterial Community Characteristics Shaped by Artificial Environmental PM2.5 Control in Intensive Broiler Houses.International journal of environmental research and public health · 2022Article
- Flock Factors Correlated with Elevated Mortality in Non-Beak Trimmed Aviary-Housed Layers.Animals : an open access journal from MDPI · 2022Article
- Investigation of Rice Yields and Critical N Losses from Paddy Soil under Different N Fertilization Rates with Iron Application.International journal of environmental research and public health · 2022Article
- Automatically Controlled Dust Generation System Using Arduino.Sensors (Basel, Switzerland) · 2022Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The EU ban on conventional barren cages for laying hens from 2012 has improved many aspects of laying hen welfare. The new housing systems allow for the expression of highly-motivated behaviors. However, the systems available for intensive large-scale egg production (e.g., aviaries, floor housing systems, furnished cages) may cause other welfare challenges. We have reviewed the literature regarding the health, behavior, production characteristics, and welfare of laying hens when exposed to ammonia in their housing environment. Concentrations of ammonia gas are commonly high in aviaries and floor housing systems in which manure is not regularly removed, whereas they are usually lower in furnished cages. High levels are found during the cold season when ventilation flow is often reduced. Ammonia is a pungent gas, and behavioral studies indicate chickens are averse to the gas. High concentrations of gaseous ammonia can have adverse health effects and, when very high, even influence production performance. The most profound effects seen are the occurrence of lesions in the respiratory tract and keratoconjunctivitis. There is also evidence that high ammonia concentrations predispose poultry to respiratory disease and secondary infections. We conclude that there are animal welfare challenges related to high ammonia levels, and that immediate actions are needed. Development of improved systems and management routines for manure removal and ventilation will be important for the reduction of ammonia levels and hence will contribute to safeguarding hen welfare.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.