Copyright © Society of Animal Science, Department of Livestock & Avian Science, Wayamba journal of Animal Science, Wayamba University of Sri Lanka
http://www.wayambajournal.com
Wayamba Journal of Animal Science – ISSN: 2012-578X; 2011
First Published October 31, 2011; Number 1320125426
SPERM ABNORMALITIES AND DNA FRAGMENTATION VIS-À-VIS
MAMMALIAN MALE INFERTILITY – A REVIEW
Siddique, R. A.
1
, Jagan Mohanarao Gali
2
, Raj Kumar
2
, Anand Kumar
3
, Malik,
P.K.
1
, Chandan Kumar.
4
and Atreja, S.K.
5
1
Navsari Agricultural University, Navsari, Gujarat, India
2
Reproductive Biochemistry Lab., Animal Biochemistry Division, N.D.R.I., Karnal,
Haryana, 132001.
3
Govt. of Veterinary Service, Uttar Pradesh, India
4
Ranchi University, Ranchi
5
Reproductive Biochemistry Lab., Animal Biochemistry Division, N.D.R.I., Karnal, Haryana,
132001.
Corresponding Author : riazndri@gmail.com
In most of the cases male infertility is due
to low spermatozoa count, poor
spermatozoa quality and DNA
fragmentation. It may be the end result of
one or more factors that include chronic
illness, malnutrition, genetic defects,
structural abnormalities, and
environmental factors. Spermatozoa
abnormalities may be classified on the
basis of site of defect and primary &
secondary abnormalities. Knobbed sperm
defect, diadem defect are the two
important defects of spermatozoa head.
Midpiece have pseudo droplet defect and
corkscrew defect whereas stump defect
and dag defect are the specialized defects
exhibited by spermatozoa tail.
Spermatozoa with normal morphology and
other parameters as motility, count etc,
may have fragmented DNA (damaged
DNA). Therefore DNA damage
assessment along with routine tests for
infertility investigations is also
recommended.
Key Words: Spermatozoa, Abnormalities,
DNA, Fragmentation, Infertility
An important part of any breeding
soundness exam is an evaluation of
spermatozoa morphology. Normal
ejaculated semen volume of human, cattle
and buffalo is 2-6 ml, 2-10 ml and 0.5-4.5
ml respectively. The normal spermatozoa
count for buffalo, cattle and human are
200-800X106/ ml, 300-2000X106 and 50-
350X106/ml respectively (Knobil and
Neill, 1998). Conventionally, the size and
shape of the head, midpiece and tail of
sperms are examined. Additional
information can be gained by evaluating
integrity of the acrosome and spermatozoa
membranes. Spermatozoa from different
species vary in size and shape. Bull and
human spermatozoa, for example, have
paddle-shaped heads, rodent spermatozoa
have hook-shaped heads, and the heads of
chicken sperm are spindle-shaped and
almost difficult to distinguish from the
midpiece. In normal spermatozoa
morphology, it counts for an oval head 4
or 5 μm in length and 2 or 3 μm in width.
The head contain nucleus with haploid
DNA complexed to nuclear proteins called
protamines. The actual amount of DNA in
the nucleus of one bull spermatozoa has
been calculated to be 3.3X10-9 mg. Sperm
from infertile animals tend to have less
DNA than normal. RNA is also present in
the nucleus of the spermatozoa, but in
small quantities approximately 0.1X10-9
mg in a spermatozoon of a bull (Frandson
and Spurgeon, 1992). The length to width
ratio should be between 1.5 and 1.75. A
well defined acrosome resides on anterior
head and should comprise 40-70% of the