Phenotypic Effects of Cattle Mitochondrial DNA in American Bison

• Published in: Conservation biology Vol. 26; no. 6; pp. 1130 - 1136
• Main Authors: Derr, James N., Hedrick, Philip W., Halbert, Natalie D., Plough, Louis, Dobson, Lauren K., King, Julie, Duncan, Calvin, Hunter, David L., Cohen, Noah D., Hedgecock, Dennis
• Format: Journal Article
• Language: English
• Published: Hoboken, NJ Blackwell Publishing Ltd 01.12.2012; Wiley-Blackwell
• Subjects: Abundance; ADNmt; altura; Ancestry; Animal genetics; Animal Nutritional Physiological Phenomena; Animal populations; Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Biometry; Bison; Bison - anatomy & histology; Bison - genetics; Bison - physiology; Body Weight; Buffalo; California; Catalina Island; Cattle; Cattle - genetics; Conservation biology; Conservation of Natural Resources; Conservation, protection and management of environment and wildlife; DNA, Mitochondrial - genetics; Environmental conservation; Feedlots; Female; Fundamental and applied biological sciences. Psychology; General aspects; Genetic Variation; Genotype & phenotype; height; Herds; hibridación; Hybridization; introgresión; introgression; Isla Catalina; Male; Male animals; Mitochondrial DNA; Montana; mtDNA; Parks, reserves, wildlife conservation. Endangered species: population survey and restocking; peso; Polymerase Chain Reaction; weight; Montana; California; INE, USA, California, Channel Is., Santa Catalina I; Catalina Island; Bovine; mtDNA; weight; Mitochondrial DNA; Hybridization; Introgression; Island; Vertebrata; Phenotype; Mammalia; Artiodactyla; Ungulata; Environmental protection; height
• ISSN: 0888-8892; 1523-1739
• DOI: 10.1111/j.1523-1739.2012.01905.x

Hybridization between endangered species and more common species is a significant problem in conservation biology because it may result in extinction or loss of adaptation. The historical reduction in abundance and geographic distribution of the American plains bison (Bison bison bison) and their recovery over the last 125 years is well documented. However, introgression from domestic cattle (Bos taurus) into the few remaining bison populations that existed in the late 1800s has now been identified in many modern bison herds. We examined the phenotypic effect of this ancestry by comparing weight and height of bison with cattle or bison mitochondrial DNA (mtDNA) from Santa Catalina Island, California (U.S.A.), a nutritionally stressful environment for bison, and of a group of age-matched feedlot bison males in Montana, a nutritionally rich environment. The environmental and nutritional differences between these 2 bison populations were very different and demonstrated the phenotypic effect of domestic cattle mtDNA in bison over a broad range of conditions. For example, the average weight of feedlot males that were 2 years of age was 2.54 times greater than that of males from Santa Catalina Island. In both environments, bison with cattle mtDNA had lower weight compared with bison with bison mtDNA, and on Santa Catalina Island, the height of bison with cattle mtDNA was lower than the height of bison with bison mtDNA. These data support the hypothesis that body size is smaller and height is lower in bison with domestic cattle mtDNA and that genomic integrity is important for the conservation of the American plains bison. La hibridación entre especies en peligro y especies más comunes es un problema significativo en biología de la conservación porque puede resultar en la extinción o pérdida de adaptación. La reducción histórica de la abundancia y distribución geográfica del bisonte americano (Bison bison bison) y su recuperación en los últimos 125 años esta bien documentada. Sin embargo, la introgresión de ganado doméstico (Bos Taurus) en las escasas poblaciones remanentes de bisonte que existían a fines del siglo XIX ha sido identificada en muchas manadas actuales de bisonte. Examinamos el efecto fenotípico de esta ascendencia mediante la comparación del peso y altura de bisontes con ADN mitocondrial (ADNmt) de ganado o bisonte de la Isla Santa Catalina, California, (E.U.A.), un ambiente nutricionalmente estresante para bisontes, y de un grupo de bisontes machos de la misma edad de Montana, un ambiente nutricionalmente rico. Las diferencias ambientales y nutricionales entres estas 2 poblaciones de bisontes fueron muy grandes y demostraron el efecto fenotípico del ADN mt de ganado doméstico en bisontes en un amplio rango de condiciones. Por ejemplo, el peso promedio de machos de 2 años de Montana fue 2.54 veces mayor que el de machos de la Isla Santa Catalina. En ambos ambientes, los bisontes con ADNmt de ganado tenían menos peso en comparación con bisontes con ADNmt de bisonte, y en la Isla Santa Catalina, la altura de bisontes con ADNmt de ganado fue menor que la altura de bisontes con ADNmt de bisontes. Estos datos soportan la hipótesis de que el tamaño corporal es menor y la altura es menor en bisontes con ADNmt de ganado y que la integridad genética es importante para la conservación del bisonte americano.