All isolates from humans had spoligotype patterns that matched those observed in the cattle isolates, and all human isolates shared common ancestors with cattle in Baja California based on SNP analysis. This suggests that most human tuberculosis caused by M. bovis in Baja California is derived from M. bovis circulating in Baja California cattle. These results reinforce the importance of bovine tuberculosis surveillance and control in this region.

Captive breeding programs and aquaculture production have commenced worldwide for the globally distributed yellowtail kingfish (Seriola lalandi), and captive bred fingerlings are being shipped from the Southern Hemisphere to be farmed in the Northern Hemisphere. It was recently proposed that Pacific S. lalandi comprise at least three distinct species that diverged more than 2 million years ago. Here, we tested the hypothesis of different “species” in the Pacific using novel genomic data (namely single nucleotide polymorphisms and diversity array technology markers), as well as mtDNA and DNA microsatellite variation. These new data support the hypothesis of population subdivision between the Northeast Pacific, Northwest Pacific and South Pacific, and genetic divergence indicates restriction to the gene flow between hemispheres. However, our estimates of maximum mtDNA and nuclear DNA divergences of 2.43% and 0.67%, respectively, were within the ranges more commonly observed for populations within species than species within genera. Accordingly our data support the more traditional view that S. lalandi in the Pacific comprises three distinct populations rather than the subdivisions into several species.

Abalone is a highly valued seafood in many parts of the world. Depending on size and species, it can fetch between US$15 and US$30 per kg in some markets. Because of its high value, abalone is cultured in several countries, including China, Australia, Japan, Chile, South Africa, Canada, Mexico, the USA and many other Asian countries, such as Thailand, the Philippines and Korea. Hybridization is widely used to improve specific traits in animal and agricultural stocks by using a new genetic conformation in the offspring. In general, hybridization offers several benefits in aquaculture conditions, such as improvements in growth rate, survival, food conversion and stress resistance (to temperature and disease). Under commercial conditions, hybrids make it possible to diversify the industry and to offer new products and gain new markets. This review examines evidence of wild and experimental hybridization among abalone species from several biogeographical areas worldwide, and provides information on the phenotype characteristics of artificially produced hybrid abalone. Genetic and phenotypic approaches were analysed to determine whether there is a relationship between the genetic variability and positive heterosis in hybrid crosses. In this review, we also reported embryonic and larval development of hybrid and genetic studies derived from gene expression analysis of thermal tolerance. Furthermore, alloenzyme, cytogenetic and molecular DNA markers were reviewed to certify the hybrid status in Haliotis. This review will also discuss the impact of intra and interspecies hybrids on abalone aquaculture worldwide.

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Evidence of hybridization in Haliotis has been mainly supported by hatchery experiences and collection of wild hybrid abalones among several species from natural populations worldwide. However, despite the importance to understand the role of the hybridization process through Haliotidae evolution, and also its impact on the abalone aquaculture, genetic studies in hybrid abalones have been poorly developed. Herein, cytogenetic approach allows studying the genetic conformation in hybrid organisms at the chromosome level. This paper reports a quantitative karyotype analysis in Haliotis rufescens, Haliotis discus hannai and their interspeci¢c hybrid. Thus, to characterize chromosome pairs and establish cytogenetic comparisons, chromosome banding with distamycin-A/4,6-diamidino-2-phenylindole £uorochromes and morphologic measurements were performed. The results showed that the hybrids are successfully viable and their karyotypes evidenced a conservative chromosome number of 2n 5 36. The karyo-idiogram showed a high correspondence in chromosome pair morphology among the hybrids and their parental species, except for a single heteromorphic pair that corresponds to the chromosome 16 from H. rufescens andH. d. hannai respectively. The implications of the abalone hybrid viability derived from its chromosome composition are discussed.

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