Intl. J. of Molecular Zoology, 2013, Vol.3, No.3, 10
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http://ijmz.sophiapublisher.com
11
ith genotypes (i= 1, 2, 3) and e
ij
is random error.
2
Results and Discussion
Present study revealed amplified PCR product on 2%
agarose gel as a single compact band of 156 bp size in
Frieswal breeds under UV transilluminator and
documented by gel documentation system. The PCR
product of the same bp size was also reported by
Kumari et al
(2008)
in exotic and Zebu cattle,
Sacravarty et al
(2008)
in Kankrej cattle, and Ghasemi
et al
(2009)
in Montebeliard cows.
Restriction digestion with
Rsa
I restriction enzyme
revealed restriction fragments of 15 682 bp and 74 bp
sizes. The different restriction fragments generated
three different RFLP patterns. The DNA restriction
fragments were obtained for the
PRL-Rsa
I
polymorphism were: for the AA genotype 156 bp (no
digestion), for the AB genotype 156 bp, 82 bp and 74
bp and for the BB genotype 82 bp and 74 bp. These
three different RFLP patterns were obtained at two
restriction sites corresponding to AA, AB and BB
genotypes. Similar RFLP patterns using
Rsa
I
restriction enzyme were reported by Kumari et al
(2008)
in exotic and Zebu cattle, Sacravarty et al
(2008)
in Kankrej cattle and Ghasemi et al
(2009)
in
Montebeliard cows.
The genotypic frequencies for AA genotype 0.315 for
AB genotype 0.629 and for BB genotype 0.056
whereas, allelic frequencies for A allele 0.630 and for
B allele 0.370 in Frieswal cattle breeds. The
significant (P˂0.05) Chi-square value for all the
genotypes in Frieswal cattle showed that the
population was not in Hardy-Weinberg equilibrium.
Similar results were reported by Klauzinska et al
(2004)
in Polish Red and Polish Black and White
cattle, Brym et al (2005) in Jersey and Black and
White cattle and Skinkyte et al (2005) in Lithuanian
Black and White and Lithuanian Red cattle. The
results obtained in the present study are not in
agreement with those reported by Alipanah et al
(2007
a) in Red Pied cattle, Alipanah et al (2007b) in
Russian Black Pied and Red Pied cattle and Alipanah
et al (2008) in Russian Black Pied and Red Pied cattle.
The significant (P<0.05) Chi-square value indicates
that the animals differ in their genotypic distribution
in respect to gene frequency. The deviation in
observed and expected genotypic frequencies among
all these breeds may also be due to small population
size and selective breeding. The result of analysis of
variance showed non-significant effect of genotypes
on lactation length, lactation yield and service period
in Frieswal cattle breeds may be due to small sample
size resulting in higher error variance. The result of
analysis of variance showed non-significant effect of
genotypes on lactation length, lactation yield and
service period in Frieswal cattle breeds may be due to
small sample size resulting in higher error variance.
Non-significant differences were observed between
mean lactation length and lactation yield among
various genotypes. However, the significant (P<0.05)
differences between mean service period of various
genotypes was observed in Frieswal cattle breed. Less
number of days for service period was observed for
AA genotype in Frieswal cattle, which indicates
superiority of AA genotype as compared to AB and
BB genotypes.
Mean performance of genotypes showed non-significant
(
P<0.05) differences among genotypes for lactation
length and lactation yield. Though the differences
among genotypic means were non-significant but
superiority of BB genotype for lactation length
(329.14
days) and AB genotype for lactation yield
(3161.19
kg) were seen among all the three genotypes.
Non-significant association of lactation length was
reported by Aravindakshan et al (2004) in Vechur and
Kassargode cattle. The results revealed in the present
study are in accordance as reported by Alipanah et al
(2007
a) in Russian Red Pied cows, Alipanah et al
(2007
b) in Russian Black Pied and Russian Red Pied
cows, Alipanah et al (2008) in Russian Black Pied and
Russian Red Pied cows, and Ghasemi et al (2009) in
Montebeliard cows. Non-significant association of
lactation yield was reported by Aravindakshan et al
(2004)
in Vechur and Kassargode cattle, Khatami et al
(2005)
in Russian and German Black and White and
Yaroslavl cattle breeds and Sacravarty et al (2008) in
Kankrej cattle.
Mean performance of genotypes showed significant
(
P<0.05) differences for service period. The genotype
AA (117.45 days) seems to be superior for service
period among the three genotypes. Non-significant
association of service period was reported by
Sacravarty et al (2008) in Kankrej cattle. Hence, it can