ISSN 2375-0863
African Journal of Poultry Farming ISSN: 2375-0863 Vol. 6 (5), pp. 290-300, September, 2018. © International Scholars Journals
Full Length Research Paper
Ecotype differences in growth and behavioural responses to low energy diets in Tanzanian local chickens
Khondowe Paul1⃰ , Mutayoba Benezeth2, Muhairwa Amandus2 and Phiri Elliot3
1College of Veterinary Medicine and Biomedical Sciences, Department of Physiology, Biochemistry and Pharmacology; Sokoine University of Agriculture, P.O. Box 3017, Morogoro, Tanzania.
2Department of Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania;
3Department of Biological Sciences, School of Natural Sciences, The University of Zambia, P.O. Box 32379, Lusaka, Zambia.
Corresponding author E-mail: [email protected]; Tel: +260977442669
Accepted 31 October, 2017
Abstract
A study was conducted to compare growth and behavioural responses to low dietary energy in three chicken ecotypes at 4 weeks old for 7 weeks. 351 hens belonging to Kuchi (KU), Ching’wekwe (CH) and Morogoro medium (MM) ecotypes were allocated to 9 pens in a 3 x 3 factorial design, with 3 replicates. They were fed 3 diets containing 40, 55 or 0% less energy than a prescribed control diet. Low dietary energy increased feed intake but reduced growth rates in all ecotypes. Among 40% restricted groups, KU had significantly higher (p<0.05) weight gains, whereas MM had higher (p<0.05) weight gains and lower feed conversion ratio (FCR) at 55% restriction. Body lengths, shank lengths, chest circumferences and wing spans for KU and CH but not MM were markedly (p<0.05) reduced for both restricted groups. Foraging and feeding behaviours were higher in restricted groups of all ecotypes in the third week. MM had least mortality in both restricted groups and controls. Results of this study show ecotype-specific tolerance to low dietary energy through differences in growth performance, FCRs and behavioural responses. MM showed better tolerance at the lowest energy level whereas KU exhibited better performance at 40% and control energy levels.
Key words: Behaviour, foraging, morphometric, restriction, stress, tolerance.