| dc.description.abstract | Extensive use of synthetic growth promoting antibiotics have become a threat to
public health. Therefore, there is a need to search for bioactive phytochemicals that
have positive effects on immune, growth and appetite status of the chicken. Such
bioactive compounds can be obtained from plants. Pumpkin seeds have been found to
be a valuable source of protein and bioactive compounds. Mathematical models have
been used to study the effect of pumpkin extracts on the weight gain of chicken.
However, most of these studies have focused on the levels of the application of
pumpkin extract, rather than on optimising the levels of application on the weight gain
of the chicken. Optimization is important since it provides information on the amount
of pumpkin seed extracts that should be fed to the chicken without wastage. This
study was conducted to evaluate the weight gained by the Kenbro chicken served with
pumpkin (Cucurbita pepo L) seeds extract and examined the possible combination of
the number of weeks and quantity of pumpkin seed extract that can result in
maximum weight gain of the Kenbro chicken. The experiment was conducted using
Random Complete Block Design at the poultry demonstration unit of Chuka
University. Sixty- day old Kenbro chicks were randomly distributed to five treatments
which contained 0, 50, 100, 150 and 200 ml of pumpkin seed extracts per litre of
water. Each treatment was replicated three times with four chicken per replicate. The
birds were fed with the same diets of finisher and starter feeds. The chickens were
provided with enough feeds and water ad libitum in the morning at 8 am. The birds
were weighed at the beginning of the experiment and thereafter at an interval of three
days for eight weeks. Data was analysed using R statistical software. A Response
surface model was fitted to the data and subjected to contour plots to characterize the
nature of its turning point and to capture the combination of the number of weeks and
quantity of pumpkin seed extract that brings maximum weight gain of the Kenbro
chicken. The results showed that the average body weight gained was significant (p <
0.05). The birds served with 200 ml pumpkin seed extract for 4 weeks had the highest
weight gain. The fitted Response Surface Model indicated that the number of weeks
and quantity of pumpkin seed extract together with their interaction significantly (p <
0.05) determined the weight gain of Kenbro chickens. The study found that the
quadratic model fitted using the data had an adjusted R-Squared value of 0.78. The
optimal weight gain of 0.23 kg was achieved when the number of weeks was 3.18
with 192.40 ml of pumpkin seed extract. The number of weeks, pumpkin seed extract
and their interaction play a key role in obtaining maximum weight gain of the Kenbro
chicken. These factors should be put into consideration when developing a feeding
system for Kenbro chickens. The study also guides the farmers on the optimization of
Kenbro chicken production without incurring an extra cost in the input. | en_US |
