| Sumario: | The purpose of this study was to investigate the potential in meat production traits of some of the many types of indigenous chickens in Ethiopia. From the various strains of birds locally found, 5 distinct types -Tikur, Melata, Kei, Gebsima and Netch -as they are locally known, were collected and their meat production characters tested at the Awassa Junior College of Agriculture, Awassa, Sidamo. As a control group Single Comb White Leghorn chickens were used in the study. The experiment was run between October 1982 and1984 both on parental stock as well as on progenies produced from the parental populations. Economically important parameters like feed consumption, body weight, egg number, egg weight and hatchability of the parental population and growth rates, organ weights and dressing percentage of the progenies were measured. Biometerological variables like temperature, relative humidity, radiation intensity and wind velocity as influencing factors of the animals' productive characters, were also measured. The data thus collected on both parental and progeny populations were subjected to an analysis of variance. The differences between means whenever significant were tested by the use of the DUNCAN Multiple Range Test. Regression analyses were carried out to test the relation- ship between the various independent and dependent variables. Correlation and regression relationships between biometerological factors and the different economic traits were also calculated. The main points resulting from the study could be enumerated as follows: 1. The mean mature body weight of the local ecotypes was 1.38 kg and equalled 85 percent of the Leghorns' weight. Individual strain mature body weights were Gebsima: 1.30 kg, Tikur: 1.35 kg, Kei: 1.36 kg, Netch: 1.42 kg, Melata: 1.48 kg and Leghorn: 1.62 kg. Effects of climatically changes on mature body weights were not significant. 2. The local chickens' rates of egg production were approximately 18 percent and those for the Leghorns were 26 percent. Genetic environmental interaction became apparent. The local ecotypes maintained egg production rates until the end of their second year of age, while the Leghorns were almost out of production at the same time. Increasing environmental temperature depressed egg production more in the Leghorn chickens than it did in the local animals. 3. Egg weight was positively correlated with mature body weight (r = 0.67, P<0.01). The egg weights were 46 and 64 g both in the local ecotypes and the Leghorns, respectively. 4. Mean monthly temperatures ranging between 22 and 26° C did not influence egg weight significantly. Genetic differences were more influential than those caused by biometerological changes. 5. The total egg-mass was influenced more by the number of eggs than by the weight of the individual egg. 6. Indigenous chickens' eggs contained relatively more yolk than those of the Leghorns, the difference being 8 percent. 7. The fertility of eggs in the local groups was better than in the Leghorns. The average fertility in the local chickens was 56.4 and 46 percent in the Leghorns. 8. Fertility was inversely related with sunshine length, dry-bulb temperature and radiation intensity with correlation coefficients, of -0.40 (P<0.0l), -0.32 (P<0.01) and -0.26 (P<0.05), respectively. 9. Hatchability of both total and fertile eggs was inversely (r = -0.56'and -0.48, P<0.0l, respectively) related with egg weight. And the larger sized Leghorn eggs' hatchability was at a disadvantage compared to that of the local ecotypes' eggs. Hatchabilities of both total and fertile eggs in the local strains therefore were superior by as much as 40 and 30 percent respectively. 10. Hatchability was highly correlated (r = 0.79, P<0.01) with egg fertility and it is believed that factors affecting fertility could equally influence the hatching power of chicks. 11. Feed intake was influenced by environmental factors. Birds consumed more feed during rainy season as opposed to the drier one. The difference between these 2 seasons in feed intake was 0.67 kg (16 percent) per bird per month. In general. seasons associated with lower dry-bulb temperatures showed increased rates in feed consumption. 12. The daily growth rates of the progeny up to 6 months of age were Kei: 5.04 g. Gebsima: 5.11 g. Tikur: 5.16 g, Melata: 5.36 g. Netch: 6.38 g and Leghorn: 8.98 g. The combined growth rate of 5.41 g for the local ecotypes was significantly lower (P<0.01) than the Leghorn rate. The Netch and Melata strains among the local groups were fast growing. 13. Body weights of the various genotypes in the progeny were Tikur: 450 and 960 g. Melata: 550 and 1000 g, Kei: 500 and 940 g. Gebsima: 510 and 950 g, Netch: 500 and 1180 g and Leghorn 800 and 1660 g. at 3 and 6 months of ages respectively. Thus the local ecotypes averaged 63 percent of the Leghorns body weight at 3 months and 61 percent at 6 months of age. 14. At 6 months of age. mean carcass weights were Gebsima: 510 g. Tikur: 550 g, Kei: 556 g, Melata: 568 g. Netch: 611 g and Leghorn 875 g. The pooled carcass mean weight of 559 g for the local chickens at this age was significantly smaller than the Leghorn weight (P<0.01). 15. The dressing percentages for the various genotypes at 6 months of age were Netch: 51.5. Leghorn: 52.0. Gebsima: 53.8. Melata: 56.0. Tikur: 56.4 and Kei: 57.8. The local ecotypes (pooled) had a 6 percent higher dressing percentage relative to their body sizes. than the Leghorns. 16. The hatching season July -September was shown to be favorable for body weights at 6 months of age. Birds hatched during this season had the largest mean body weights between 3 and 6 months of age. The mean body weights for the 4 hatching seasons were: 1. April June 703 g., 2. July September 975 g., 3. October -December 898 g and, 4. January -March 747 g. 17. The local ecotypes generally manifested poor performance in body weight egg weight and in rate of egg production when compared to the Leghorn levels. Under improved nutritional as well as management conditions they could not successfully compete with the improved exotic stocks at least with their present genetic constitution.
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