Dual-purpose production of genetically different chicken crossbreeds in Ethiopia. 1. Parent stocks' feed intake, body weight, and reproductive performance
. Poultry science 2019
, 3119-3129. Publisher's VersionAbstract
A total of 6 chicken parent stocks (PS) bred by European companies, and 1 local PS, were evaluated under Ethiopian condition for their reproductive performance, to be followed by testing dual-purpose performance of their crossbreed progeny. The imported PS were Lohmann Brown (LB), Lohmann Dual (LD), NOVOgen Brown (NB), NOVOgen Color (NC), Dominant Sussex (DS), and Dominant Red Barred (DR); Koekoek (KK) was obtained locally. They were reared in replicated floor-pens from 16 to 60 wk of age, and evaluated for feed intake, body weight (BW), egg production, fertility, and hatchability. In total, 1,810 females and 261 males were distributed over 4 houses in randomized blocks design. Additionally, 3 experimental crosses, R × K (DR females × KK males), S × R (DS females × DR males), and K × S (KK females × DS males) were evaluated for fertility and hatchability. The PS differed in BW, feed intake, age of sexual maturity, egg production, fertility, and hatchability. Among females, DR and DS had the highest BW, whereas LB, NB, and NC had the lowest BW. Final mean BW of the parental meat-type males of NC and LD were the highest (5,027 and 3,660 g, respectively), whereas the other parental males ranged from 2,585 to 2,955 g. Fertility of NC and LD was low because the heavy parental males had difficulty to mate naturally their small-body female mates. However, with artificial insemination (AI), fertility of NC and LD was between 75 and 80%, similar to the other 5 PS. The fertility and hatchability of eggs laid by DR, DS, and KK hens was improved by 6.3% in the experimental crosses, where these hens were mated with genetically different males. The LD hens exhibited the highest overall laying rate (64.2%) during the study period, and with AI, hatchability of LD eggs (66.6%) was the highest, making it the best chick producer. Thus, despite its high total feed intake (but similar to DR, DS, and KK), LD (followed by DR) was the best PS in this study under floor management in Ethiopia. Published by Oxford University Press on behalf of Poultry Science Association 2019.
Dual-purpose production of genetically different chicken crossbreeds in Ethiopia. 2. Egg and meat production of the final-crossbreed females and males
. Poultry science 2019
, 3405-3417. Publisher's VersionAbstract
Females and males of 7 commercial (ComCb) and 3 experimental (ExpCb) crossbreeds were produced by 6 imported parent stocks (PS) and 1 local PS. The ComCb were Dominant Red Barred (DR), Dominant Sussex (DS), Lohmann Brown (LB), Lohmann-Dual, NOVOgen Brown (NB), NOVOgen Color (NC), and local Koekoek (KK). The ExpCb were (dams × sires) DR × KK (R × K), DS × DR (S × R), and KK × DS (K × S). The females were reared to 60 wk of age, and recorded data included BW, BWG, feed intake, egg number, and egg weight, allowing the calculation of egg mass and feed conversion ratio (FCR). The males were reared to 16 wk of age and recoded data included feed intake, BW, FCR, and carcass characteristics. A total of 621 females and 516 males were tested in sex-separated trials, each with 3 replicated floor pens per crossbreed. The overall value of each crossbreed was determined by overall egg production, 60-wk BW and FCR of females, and by 16-wk BW, carcass yield, and FCR of males. The highest laying rate was exhibited by LB (68%) and NB (66%), followed by RxK and K × S (∼62%). The crossbreeds differed in feed intake and in females' FCR, with LB leading (2.74) followed by NB and S × R (3.07) then DR (3.18). In egg production, LB, followed by NB, were the best, as expected from specialized table-egg crossbreeds. The highest 16-wk BW of males and best FCR were exhibited by NC, followed by NB. In summary, LB was the best egg-producing crossbreed, but poor in meat production. Better choice for dual-purpose production would be NB, ranked second in egg production and in males' BW and FCR. NC was the best meat-producing (males and spent hens) crossbreed and the hens were second in egg-mass production. Hence, NC might be the best dual-purpose hybrid where artificial insemination is feasible and the consumers prefer large eggs and birds. Published by Oxford University Press on behalf of Poultry Science Association 2019.