Relationships between tumbling behavior and brain morphology and histology in pigeons

Many pigeons breeds were found in widely breed for commercial purposes and hobby that they show highly significant deviation from the origin specie in terms of both morphological and behavioral characters. The purpose of this study was to compare the brain morphology and histology of pigeon genotypes with and without tumbling behaviour.. In this study as materials were used brain tissue sections from 24 pigeons of Baska, Homer and Turkish Tumbler genotypes. The brain tissues were stained with the H & E method.The gross brain weight was significantly different regarding gender (P = 0.011). Furthermore, the Turkish Tumbler pigeons have a significantly lighter brain than the other breeds (P = 0.003).All genotypes were evaluated together in the allometry equations and regression coefficients gross brain weight and live weight, gross brain weight and carcass weight were b = 0.31 (P = 0.004) and b = 0.27 (P = 0.007), respectively. A large part of the values of the Turkish Tumbler pigeons were below the regression line contrast to the other breeds.Genotype and gender effects were not significant on the width of molecular strata, granular strata and white matter in cerebellum (P ? 0.2013). While genotype and gender effects were significant, in terms of purkinje cell frequency per mm2. The Baska pigeons have significantly fewer purkinje cells per sq mm (P = 0.0400). As a result of the qualitative evaluation of brain tissue preparations, differences could not be established between the breeds.The conventional and allometric comparison of brain weights indicates a much smaller brain of Turkish Tumbler pigeons in compare to the other breeds. However, no significant differences were found between the tumbling and non tumbling pigeon breeds in terms of other observed traits.As a result, both classical and allometric comparison show that Tumbler pigeons have a much smaller brain weight. However, the explanation of the tumbling behaviour in the level of brain physiology needed more basic research.