Not AvailableBull spermatozoa contain different functional genes and many of them plays important roles in different
stages of spermatogenesis, spermatozoa kinetics, fertilization as well as embryonic development. RNA
deep sequencing is one of the preferred tools for absolute quantification of messenger RNA. The intention
of the current study was to investigate the abundance of spermatozoal transcripts in categorized Frieswal
(Holstein-Friesian X Sahiwal) crossbred bull semen through RNA deep sequencing. A total 1546561 and
1019308 numbers of reads were identified among good and poor quality bull spermatozoa based on their
conception rate. Post mapping with Bos taurus reference genome identified 1,321,236 and 842,022
number of transcripts among good and poor quality RNA libraries, respectively. However, a total number
of 3510 and 6759 functional transcripts were identified among good and poor quality bull spermatozoa,
respectively. Most of the identified transcripts were related to spermatozoa functions, embryonic
development and other functional aspects of fertilization. Wet laboratory validation of the top five
selected transcripts (AKAP4, PRM1, ATP2B4, TRIM71 and SLC9B2) illustrated the significant (p < 0.01)
level of expression in the good quality crossbred bull semen than the poor quality counterparts. The
present study with comprehensive profiling of spermatozoal transcripts provides a useful non-invasive
tool to understand the causes of as well as an effective way to predict male infertility in crossbred bulls.Science and Engineering Research Board, Government of Indi
