Survivability of pure and cross bred chickens at early and late growth phases in Nigeria humid tropics

Survival is a general measure of an animal's fitness. In commercial poultry production, mortality can result from a range of conditions (disease, physiological stress, environmental condition and aggressive behaviour. This study was aimed at evaluating Yoruba Ecotype Chicken (YEC), Sussex (SS), Goliath (GG), Marshall (MM) and their crossbred offspring for survivability in the Nigeria humid tropical climate. A total of 529chicks were raised fromday-old to 8 weeks (early growth phase) and 9 weeks to 20 weeks of age (Late growth phase). Data obtained were subjected to the Kaplan meier survivability test using SPSS (2012) version 21. The findings of the study revealed that at early growth phase, pure bred YEC x YEC had highest survivabilityof 91.20% while crossbred YEC x GG had the least survivability rate of 75.00%. The overall survivability of 86.40% was recorded at this stage. Late growth phase recorded highest survivability (100%) for cross bred YEC x GG while cross bred YEC x MM had the least survivability of 87.50% while the overall survivability was 94.10%. This study concluded that YEC are hardy compared with other genotypes, especially at the early growth phase while cross breeding improved the performance of YEC x GG at the late growth phase. The study recommends that YEC should be used as terminal sire in crosses involving exotic breeds for proper adaptability and performance in the Nigeria humid tropics.