Effects of crossing Finnrams with Awassi sheep on prolificacy and other quantitative traits
2003
Al-Wahab, R.M.H. (University of Mu`tah, Karak (Jordan). Dept. of Animal Production, Coll. of Agriculture)
An experiment lasting almost 10 years was conducted to investigate the effects of crossing 6 Finnish landrace rams with 60 Awassi ewes on prolificacy and other traits using (A.1.) first generation was produced (50% Finnawassi). Blood samples were taken for haemoglobin typing. Finnawassi ewes were back crossed to produce 75% Finn and 25% Finnawassi. A comparison was done between different Finncrosses on suitable crossbred generation in sustaining sub-tropical conditions and heat-tolerance; prolificacy, growth and conformation. Twining % in local Awassi was increased from 5 to 35% within 9 generations (+30%). Crosses of 50 and 25% Finnawassi were found more suitable for local sub-tropical prevailing conditions than 75% Finncross. These were lower tolerance to hot and harsh conditions, suffer higher mortality and less hardiness than other crosses. Although 1st generation lambs had significantly lighter weaning weights (P less than 0.05) than local Awassi (20.4 vs 24.3 kg). However, Finnawassi had much better growth rates than Awassi (264 vs 221 gm per day). Tail length in Finnawassi was reduced significantly by greater than 26% (20.9 vs 15.4 cm) and tail width was also reduced significantly by greater than 48%. It is concluded that it is worth crossing local Awassi with prolific (i.e Finnsheep) breeds to improve prolificacy, growth rate and reduce tail size in 50 and 25% Finncrosses under well managed farms.
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