Sire Selection Programme
With the objective
of identifying the most suitable bulls as the sires for the next
generation, the KLDB ventured into the field progeny-testing programme
involving the two basic tasks viz.,
1. Production of the required number of daughters per bull in
the progeny testing programme and
2. Milk recording of all available daughters of each bull to assess
its production potential
The
progeny-testing programme was started as a joint project of the
State and Central Government in 1977.
Considering the density of cattle population and diversity in the
geography among the locations, the ICDP regions of Mavelikara, Kanjirappally,
Vaikom and Kattappana were selected for carrying out the inseminations
using semen from the young Sunandini bulls (test bulls)
1500
test inseminations are being carried out using semen from each bull
tested with the intention of obtaining at least 50 completed first
lactation records from the progeny. Due to reasons like migration,
death etc. a considerable proportion of the female calves born to
the test bulls would not be available with the farmers when they
reached the first calving and the ensuing lactation stage. Non identification
of the female calves born out of test inseminations is also a contributing
factor.
Test inseminations
Test
inseminations started during the year 1977 with 10 bulls being included
in the first batch. More than 12 lakh test inseminations had been
carried out till the end of March 2004.
Field Performance Recording (FPR)
An
effective system of FPR forms the backbone of the progeny-testing
programme. FPR refers to the methodology to record the specific
performance of an animal (milk, meat, egg, wool etc.) under normal
farm conditions in the field. FPR, in the narrow sense has the aim
to rank the animal of a defined population, based on performance
data, in order to select the best one for further breeding and to
eliminate the inferior one from the breeding system.
Upto
the end of March 2004, 72359 cows had been enrolled for milk recording
from which 56235 completed lactations were obtained. A total of
2678 cows were enrolled under the milk recording programme. 2202
animals completed their respective lactations during the same period.
The
overall milk production of daughters have been showing a steady
increase over the batches. This steady progress observed is the
result of a well organised selection programme coupled with the
improved managemental practices.
Sire evaluation
One
batch of crossbred bulls is tested every year. 1500 doses of semen
from each bull are used for test AI under the programme. 3000 doses
of semen from each bull is preserved under long storage. All the
bulls qualifying to be regular collection bulls are invariably included
under the programme. The female progeny born out of the bulls are
identified, registered and followed up at intervals of six months
till their first calving. From the first lactation records of the
female progeny (corrected for managemental influences and averaged
for each bull) the breeding value of each of the sires is calculated
and the bulls ranked accordingly. The top 10% of bulls from each
batch is used for the production of the next generation of young
bulls. Semen doses maintained under the long storage are utilised
for the purpose. Unlike in the case of exotic dairy breeds under
their home situations, the results of progeny testing of crossbred
bulls under the existing field conditions are obtained at a time
when the bull in question would have attained an age of 11-12 years.
Factors like delayed age at semen collection, higher age of the
daughters at first calving etc. contribute to the delayed results.
A
Sire directory incorporating the list of proven bulls was published
by the Board for the first time during the year 1984. From then
onwards sire directories are being published from time to time incorporating
the bulls put to test and declared proven. Bulls upto the 20th batch
have till now been included under the publications.
Purchase of superior male calves
In
line with the breeding programme envisaged for the implementation
of the breeding policy of the state, the cows being declared as
elite are inseminated with the proven bull semen and the resultant
male calves purchased and reared at the bull stations. The standard
yield fixed for making a cow eligible to be declared as elite, varies
from one PT Unit to the other. The variations are mainly due to
the fact that the average yield of the best 3% of the cows from
each PT Unit is set as the qualifying limit for that particular
unit.
Upto
the end of March 2004, 1476 male calves had been purchased from
the different progeny testing units.
Herd book scheme
The
Herd Book Scheme (financed by the Govt. of Kerala) runs complementary
to the Progeny Testing Scheme. The female progeny born to the test
bulls are identified and recorded under this scheme. They are followed
up at half yearly intervals by way of girth measurements.
Objectives of the Herd book Scheme
To
identify and register all the cross-bred female calves born
in the milk recorded area for studying their growth, productive
and reproductive performance |
To
record the heart girth circumference of the animals once in
6 months to assess the growth of animals registered in the
herd book |
To study the age at first calving and first lactation milk
yield of the animals registered in the herd book and fix standard
norms for animals to be grouped in the different registers
of the herd book |