The aim of the present study was to Inve~\igate the eflect of using the antiblotie
growth promoter flavornycin on physiOlogical and productive performance of Band ram
lambs drinking saline water. Forty growing Bartd ram lambs averaging 6 months old
and 26.0 Kg live body weight were used. A 2x2 factorial arrangement was used
consisting of two groups of drinking water, tap water, TIN (505 ppm lOS) and diluted
seawater, SW (12494 ppm TDS), two levels offlavomycin 0 and 20 mglhead and 10
animals as replicates. All groups were fed on a basal diet to cover requirements of 100
gm daily gain. Treatments continued until marketing age (12 months). Carcass traits
were measured on three animals from each group. Drinking SW reduced signifICantly the diurnal variation In rectal temperature. but
inaeased skin and coat temperatures and the diumal variation of respiration rate.
Flavomycln increased skin and coat temperatures and morning respiration rate. The
changes In lhese physiological responses indicated that drinking SW facilitated heat
stability through increasing water vaporization. Flavomycin increased heat production
and helped in increasing insulation properties 0' the superlicial layers, which wa$ the
most efficienl'in protecting grOWing lambs (rom cold stress during winter. Flavomycin addition increased packed cell volume and hemoglobin
concentration. Drinking SW decreased packed cell volume. but stimulated increasing
mean corpuscular hemoglobin concentration. Flavomyc:in Increased feed efficiency. while drinking SI/V decreased body daily
gain. tolal body weight gain. nutrients intake. and feed efficiency. Adding f\avomycin
reduced these bad effects of drinking SIN on growth periormance. Drinking SW resulted in decreaslng empty body weight and hot carcass weight
equaled to 2.642 IIg and 2.400 kg. respectively, in addition to a significant decrease in
dressing percentage by 2.954% in respect to the control group. Adding flavomycin to
the animals that drank 5W moderated thai decrease to become 1.624 kg, 1.900 kg and
2.384%, respectively. Drinking SW increased the lean percentage in the best rib cut on
the account of fat percentage. Flavomycin overcame the negCltive effects of SW on the
spleen weight. 1\ was conduded that addIng flavomycin to growing lambs un'der desert
conditions couJd reduce some bad effects of drinking SW on growth performance and
carcass trails. In addition, f\avomycin protected growing animars from cold stress
through increasing insulation properties Of the superficial layers.