6. AMERICAN UNIVERSITY OF BEIRUT (AUB) TRIAL

AUB started the trial in 1980 in collaboration with USAID. The breeding plan was to mate the Finn rams imported from Finland (6 rams) with Texel ewes. The crossbred rams (FT) produced together with the pure Finn were mated to fat-tail Awassi (AW) ewes. Information is available on the trial up to 1982 (American University of Beirut, 1982) but due to civil conditions prevailing in Lebanon, no further information could be obtained.

6.1 Reproductive performance

Due to the difficulties in copulating with fat-tail AW ewes, artificial insemination (AI) was practised. Semen characteristics and sexual activity of Finn and FT rams were studied at different times of the year, in comparison with local Awassi rams. Number of rams invilved in the trial was: 1 Finn, 2 FT and 1 AW. Higher sperm concentration and better sperm motility and sexual activity were found in AW rams than Finn during late summmer, autumn and spring with no seasonal fluctuations in percentage of living spermatozoa. On the other hand, no seasonal fluctuations were reported in semen characteristics or sexual activity of Finn and FT rams. In all breed groups studied, low values for spermatogenesis were recorded during early summer due to high ambient temperature.

Sixty-one and 76 AW ewes were artificially inseminated in the autumn of 1980 and 1981 respectively, using fresh semen from FT rams. Each ewe received on the average 3 inseminations/heat. Lambing rate averaged 80 percent, and was the highest for the fresher semen. Gestation length of AW ewes inseminated was 147 days with a range of 144-151 days. Number of lambs born per AW ewe lambed was 1.02 lambs in 1981.

6.2 Performance of Finn cross lambs

Birth weight of FT x AW (FTA) crossbred lambs did not differ significantly from AW lambs; 3.91 vs. 3.5 kg, respectively (Table 20). At 10 weeks of age the differences became statistically significant for ram-lambs in favour of the crossbred lambs (17.7 vs. 14.4 kg, respectively) while it was non-significant for ewe-lambs (14.9 vs. 14.8 kg, respectively). At 20 weeks of age the differences were 2.6 kg for ram-lambs and 1.1 kg for ewe-lambs. Eight crossbred lambs out of 50 died, 4 of them within the first 2 weeks.

FTA ram-lambs reached puberty early at 6-7 months old, while only 33 percent of FTA ewe-lambs reached puberty by that age. Genes responsible for early sexual maturity are transmitted through crossing with Finn sheep.

Data on slaughtering one single FTA lamb were reported with 37.8 kg slaughter weight and a dressing percentage of 43.9. Weight of internal fat was 0.79 and fat-tail was 0.5 kg.

Table 20: Performance of FT x AW vs. AW lambs in Lebanon.