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Vanaraja, a new breed of poultry bird suitable for backyard farming in rural and tribal
areas, has been developed by the project directorate on poultry, an outfit of the Indian
Council for Agricultural Research (ICAR), Rajendranagar, Hyderabad. The Vanaraja poultry
is beautiful and resembles the desi bird at the same time. It displays better immunity to
diseases than many other poultry birds. Vanaraja birds can be reared in the kitchen garden
as backyard poultry farming by feeding them kitchen and agriculture waste.
Vanaraja is the best choice for backyard farming due to the bird’s genetic architecture
along with high immune status for common poultry diseases. Due to its moderate weight
and long shanks, the bird is able to protect itself from predators. A crossbreed between
indigenous and exotic varieties, Vanaraja has attractive feather color pattern and better
survivability. Its features include better feed efficiency, low input cost and larger egg size.
The desi hens can also hatch Vanaraja eggs. Compared to indigenous fowl, a matured Vanaraja
weighs about 500 to 700 g and produces nearly 100 more eggs. They can be let free for
scavenging in the backyard surrounding the house after four to six weeks of age. Vanaraja
is a dual purpose bird which can be reared either for meat or egg production. The bird
easily adapts to even adverselocal climatic conditions like extreme cold or hot.
Without extra feeding efforts, the Vanaraja male bird attains moderate body weight
within eight weeks. The female bird lays between 160 and 180 eggs in a laying cycle. The
Vanaraja variety is considered to be the best poultry breed to boost rural poultry production.
Now it is being distributed for on-farm testing. Traditional system of backyard poultry
keeping with indigenous birds predominates and it is the only means to fulfill the demands
for eggs and meat from rural farm families and meet the urban supply. It is also the most
important cash income source during economic difficulties. Efforts are being undertaken
to produce more eggs and chicken meat to meet the needs of growing human population
through introduction of ‘Vanaraja’—which yielded more eggs. Given the importance of
agriculture and livestock in the northeast, there is immense scope for the development
of livestock and poultry in the region.
Keeping in view the importance of the development of Vanaraja bird, efforts have
been made to estimate and compare different nonlinear growth models to examine the
suitable model for the growth of body weight of Vanaraja bird. Generally, in life sciences,
the linear growth models do not perform better and the nonlinear models give better
estimates. Nonlinear models are estimated by a number of researchers in the case of
turkeys, birds, cattle and poultry. Brown et al. (1976) estimated five nonlinear models,
which were used to fit weight-age data for female cattle of diverse breeding and
management. Comparisons were made among these models for goodness of fit, biological
interpretability of parameters and computational ease. Norris et al. (2007) estimated three
different nonlinear models, namely, Gompertz, Logistic and Richards for chickens. Models
were compared using coefficients of determination (R2 values), parameter values, the
Durbin-Watson (DW) statistic test for autocorrelation, computing difficulty based on the
number of iterations needed for convergence and size of residual variances. Anthony et
al. (1991) examined the pattern of growth from hatch to sexual maturity in quail, chicken
and turkey females using the Gompertz equation. Sezer and Tarhan (2005) focused on a
comparison of the growth characteristics and parameters of three meat-type lines of
Japanese quail. The body weight data of wild-type, dotted-white and extended-brown
quail lines over time were collected and fitted to Richards equation. The relevant
parameters were compared based on the Confidence Interval Test. Overall model predictions
for male brown and white quails and for female brown and wild-type quails showed the
largest differences. Like in males, white and wild females were the closest lines, but the
likeliness percentage was lower than that for males. The proposed method of parameter
comparison can be a useful tool for researchers working on biological modeling. Sengül
and Selahattin (2005) estimated the growth curves of male and female turkeys with respect
to their live weight-age relationship and determined a nonlinear model, explaining their
growth curve better. For this purpose, four different nonlinear models were used to define
growth curves of turkeys, namely, Gompertz, Logistic, Morgan-Mercer-Flodin (MMF) and
Richards. The coefficients of determination for these models were 0.9975, 0.9937, 0.9993
and 0.9966 for females and 0.9974, 0.9933, 0.9993 and 0.9969 for males, respectively.
Considering the model selection criteria, Gompertz, Logistic and Richards models seem to
be the suitable models for explaining large white turkey growth.
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