2 research outputs found
Effects of duration and level of feed restriction on performance and meat quality of broiler chickens
Two hundred and sixteen unsexed 14 days-
old Marshall broiler chicks were used in a 3脳3
factorial experimental design to test the effect of
restricting feed intake of birds by 0 %, 20 % and
40 % levels for 2, 4 and 6 weeks after two weeks
of the starter phase. The unrestricted (control)
treatments were fed ad libitum throughout the
experiment. The experiment lasted for 42 days.
Data were collected and calculated on weight
gain, feed:gain, feed intake, mortality, proximate
composition of meat and cost-benefit analysis.
Data obtained were subjected to a 2-way analysis
of variance. Results showed significantly higher
(p<0.05) final weights in the unrestricted birds
(control) compared to the restricted birds.
Interaction between duration of restriction and
level of restriction indicated that weight gain and
feed intake significantly (p<0.05) reduced as
duration and level of feed restriction increased.
Feed:gain was significantly (p<0.05) different
across the treatments with birds restricted at 40
% for 6 weeks having the best feed:gain (1.91).
The mortality recorded was not significant (p>0.05)
across duration and level of restriction. Abdominal
fat decreased with increasing duration and level
of restriction with birds on 40 % level and 6 weeks
duration of restriction having the lowest fat content
(0.20 %). Crude protein content of the breast
muscle significantly increased while crude fat
content of the breast muscle significantly
decreased with duration and level of restriction.
Crude fat content was lowest at 40 % level and 6
weeks duration of feed restriction. As level and
duration of feed restriction increased, feed cost/
kg reduced. Birds restricted at 40 % level for 2, 4
and 6 weeks durations respectively had better
cost benefit than birds restricted at 0 and 20 %
levels for 2, 4 and 6 weeks durations. It can be
concluded that the best feed:gain, lower abdomi-
nal fat, higher protein and better cost benefit was
achieved in birds restricted at 40 % for 6 weeks.Durante 42 d铆as, 216 pollos broiler Marshall, de
14 d铆as, fueron empleados en un dise帽o experi-
mental factorial 3x3 para estudiar el efecto de la
restricci贸n de la ingesti贸n de alimento en 0, 20 y
40 %, durante 2, 4 y 6 semanas en la fase de
iniciaci贸n. El tratamiento control (no restringido)
recibi贸 alimentaci贸n ad libitum durante todo el
experimento. Se obtuvieron datos sobre ganancia
de peso, alimento/peso, ingesti贸n, mortalidad,
composici贸n de la carne y relaci贸n coste benefi-
cio. Los datos obtenidos se sometieron a un
an谩lisis de varianza de dos v铆as. Los resultados
mostraron mayor peso final (p<0,05), en las aves
sin restricci贸n, la interacci贸n duraci贸n*nivel de
restricci贸n indic贸 que tanto la ganancia de peso
como la ingesti贸n, se redujeron cuando aumenta-
ron la duraci贸n y nivel de restricci贸n. La relaci贸n
alimento/ganancia fue diferente (p<0,05) entre
tratamientos siendo la mejor (1,91) en las aves con
restricci贸n de 40 % durante 6 semanas. No hubo
diferencias (p>0,05) en la mortalidad registrada.
La grasa abdominal disminuy贸 al aumentar la
duraci贸n y nivel de restricci贸n, alcanzando el
menor contenido (0,20 %) en los niveles m谩s
intensos de restricci贸n. El contenido proteico de la
pechuga aument贸 y su contenido graso se redujo
al aumentar el tiempo y nivel de restricci贸n. El
contenido graso fue igualmente menor en los
niveles mas intensos de restricci贸n. Cuando la
restricci贸n se hac铆a mayor, el coste por kg produ-
cido se reduc铆a. Las aves con restricci贸n del 40
% tuvieron en todo el tiempo mejor relaci贸n coste
beneficio que las de control y las de restricci贸n del
20 %. Se puede concluir que con la restricci贸n del
40 % durante seis semanas se consigue mejor
transformacion de alimento, menor grasa abdomi-
nal, mayor cantidad de prote铆na, y mejor relacion
coste beneficio