The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in ...The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in the tropics. Monitored three batches of approximately 18,000 females each （one for each genetic type）, from weeks 24 to 64, according to the conditions of handling and power described by the generic lines distribution companies. Although no differences were found for feed intake, Cobb Avian was presented a lower rate of feed conversion, being also that presented the highest percentage of implementation and production of incubables eggs, which meant that it was in line with the highest cumulative production of chickens by bird and week for tropical conditions studied. To adjust the lay data to a Gorssman model, in order to predict the parameters that characterize the lay modeling, estimated the best behavior for Cobb Avian 48 females, because while it takes more time to reach the level of putting constant （5.30 weeks） and maintain it for less time （2.4 weeks）, they manage to put constant high （79.11%） level, considering that the largest number of eggs per bird （171.19 vs. 164.54 and 160.11 in Arbor Acres and Ross 208, respectively）.展开更多
文摘The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in the tropics. Monitored three batches of approximately 18,000 females each （one for each genetic type）, from weeks 24 to 64, according to the conditions of handling and power described by the generic lines distribution companies. Although no differences were found for feed intake, Cobb Avian was presented a lower rate of feed conversion, being also that presented the highest percentage of implementation and production of incubables eggs, which meant that it was in line with the highest cumulative production of chickens by bird and week for tropical conditions studied. To adjust the lay data to a Gorssman model, in order to predict the parameters that characterize the lay modeling, estimated the best behavior for Cobb Avian 48 females, because while it takes more time to reach the level of putting constant （5.30 weeks） and maintain it for less time （2.4 weeks）, they manage to put constant high （79.11%） level, considering that the largest number of eggs per bird （171.19 vs. 164.54 and 160.11 in Arbor Acres and Ross 208, respectively）.
