A scoping review of the impact of heat stress on the organs of the Japanese quail (Coturnix japonica)

Abstract

Abstract Background Heat stress negatively affects poultry welfare, including the Japanese quail, especially in sub-Saharan African countries. The quail is vital to research and protein food security, which are affected by global warming. This study identified and reviewed the literature on the impact of heat stress on the Japanese quail organs to provide context for the problem and ways to mitigate it. Main body Eligible studies for this scoping review must be primarily animal-based experiments that include Japanese quail exposure to acute or chronic heat stress. Systematic reviews, theses and dissertations that meet these criteria were also eligible for use in this review. Reports that involved other types of quail species, eggs and or cell lines were not eligible and were excluded. The databases that were searched include MEDLINE (via PubMed), SCOPUS, CAB Abstracts (via CAB Direct) and Web of Sciences (All databases). A total of 4598 records were identified. After removing 105 duplicates, 4461 and 9 were excluded during the level 1 and 2 screening, respectively. Finally, 24 papers were included for data extraction. All eligible studies were primary animal experiments, and the average heat stress temperature level was 35.3 °C. Morphological findings of this scoping review include macrovesicular steatosis in the liver, necrosis of kidney tubular cells, dead and abnormal sperm cells in the testis, lung congestion, and neuronal degeneration resulting from heat stress exposure. Conclusions Heat stress negatively impacts the organs of the Japanese quail, causing cell death in the liver, brain and testis, which will affect the production and survival of the Japanese quail. In addition, some cost-effective dietary strategies tested in mitigating heat stress were recommended.