ArticlePoultry science2020
Smaller brains in laying hens: New insights into the influence of pure breeding and housing conditions on brain size and brain composition.
Article in Poultry science, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers.
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7 citing papers in PubMed.
- Rearing systems alter growth performance, behavior, brain characteristics, and meat quality in slow-growing Korat broiler chickens.Poultry science · 2026Article
- Experimental demonstration of allometric invariance of plant response to density over the course of wheat domestication.Proceedings. Biological sciences · 2025Article
- A Study on Egg Production and Quality According to the Age of Four Italian Chicken Dual-Purpose Purebred Hens Reared Outdoors.Animals : an open access journal from MDPI · 2023Article
- Investigation of structural and neurobiochemical differences in brains from high-performance and native hen breeds.Scientific reports · 2023Article
- Egg Quality of Italian Local Chicken Breeds: I. Yield Performance and Physical Characteristics.Animals : an open access journal from MDPI · 2022Article
- Data mining-based discriminant analysis as a tool for the study of egg quality in native hen breeds.Scientific reports · 2022Article
- Nature calls: intelligence and natural foraging style predict poor welfare in captive parrots.Proceedings. Biological sciences · 2021Article
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2 authors.
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Abstract
During domestication, many different chicken breeds have been developed that show many alterations compared with their wild ancestors and large variability in parameters such as body size, coloring, behavior, and even brain morphology. Among the breeds, one can differentiate between commercial and noncommercial strains, and commercial strains do not usually show variability as high as noncommercial breeds but exhibit a high production rate of eggs (or meat). The breeding of high-performing laying hens, including the housing conditions of hens, is often a focus of concern for animal welfare, and to date, little is known about the correlation between housing conditions and artificial selection on brain structure. Based on an allometric approach, we compared the relative brain sizes of 2 inbred strains of laying hens (WLA and R11) with those of 7 other noncommercial chicken breeds. In addition, we examined the brain composition of laying hens and analyzed the relative sizes of the telencephalon, hippocampus, tectum opticum, and cerebellum. Half of WLA and R11 lines were kept in floor-housing systems, and the other half were kept in a single cage-housing system. Both strains of laying hens showed significantly smaller brains than the other chicken breeds. In addition, there was a significant difference between WLA and R11 hens, with R11 hens having larger brains. There was no difference in the relative brain sizes of floor-housed and cage-housed hens. WLA and R11 hens did not differ in their brain composition, but floor-housed hens showed a significantly larger cerebellum than cage-housed hens. Apparently, pure breeding over a long time and strong artificial selection for a high production of eggs is accompanied by (unintentional) selection for smaller brains. Further studies may also reveal differences in brain composition and the influence of housing conditions on brain composition.
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