Version danRer10 for zebrafish genome in UCSC has been published for a while. our core team or big god can update it? that will be awesome 

Sooner or later the packaged annotation data will go away, and you will need to use AnnotationHub to get things you want.

> library(AnnotationHub)
> hub <- AnnotationHub()

> dr <- query(hub, c("Danio rerio"))

> grep("GRCz10", mcols(dr)$title, value = TRUE)
[1] "Danio_rerio.GRCz10.80.gtf"           
[2] "Danio_rerio.GRCz10.cdna.all.fa"      
[3] "Danio_rerio.GRCz10.dna_rm.toplevel.fa"
[4] "Danio_rerio.GRCz10.dna_sm.toplevel.fa"
[5] "Danio_rerio.GRCz10.dna.toplevel.fa"  
[6] "Danio_rerio.GRCz10.ncrna.fa"         
[7] "Danio_rerio.GRCz10.pep.all.fa"        

> dr.fa <- dr[["Danio_rerio.GRCz10.dna.toplevel.fa"]]
retrieving 2 resources
  |======================================================================| 100%
  |======================================================================| 100%

> library(Rsamtools)

> scanFa(dr.fa, GRanges("1", IRanges(1,500)))
  A DNAStringSet instance of length 1
    width seq                                               names              
[1]   500 GATCTTAAACATTTATTCCCCCT...TCTGCATAGAGCACACAAGTATG 1

> scanFa(dr.fa, GRanges(c("1","2"), IRanges(c(1,600), c(500, 1250))))
  A DNAStringSet instance of length 2
    width seq                                               names               
[1]   500 GATCTTAAACATTTATTCCCCCT...TCTGCATAGAGCACACAAGTATG 1
[2]   651 TTAAGTTTGAGGGAAGGTTGTTA...GGATCATATTTGCTGCTATTTTT 2