Live Weight Changes and Their Relationshipwith the Ovarian Status of MaidenFat-­Tailed Barbarine Ewes

The current study assessed the effect of the pattern of live weight change on the ovarian function of maiden barbarine ewesat approximately 1 year of age. for this purpose, a total of 171 weaned ewe lambs (mean live weight ± s.d. 34.7±3.07 kg and mean age± sd 196±10 days at weaning) were selected for the experiment. adjustment of live weight variation was used. based on the slope of thecurve, animals were grouped into three classes lwci (n=46), lwcii (n=91) and lwciii (n=34) with live weight loss being highest inlwci and lowest in lwciii. following laparoscopy at 13 months of age, the proportion of ewe lambs found cycling in lwciii (85.3%)was higher in comparison to animals in lwci (43.4%;; p<0.001) and tended to be superior to those in lwcii (61.5%;; p<0.05). followingsynchronisation with progestagen of the females found cycling, levels of plasma igf-­i concentrations between 6 and 42 hrs after removalof sponges were not significantly different between the three classes of live weight, and respectively averaged 94.2, 90.8 and 89.8 μg/l forlwci, lwcii and lwciii females. levels of estradiol were also not significantly different between the three groups (0.73, 0.70 and 0.67pg/ml for lwci, lwcii and lwciii ewe lambs, respectively). it was concluded that, in low input systems of semi-­arid and arid tunisia,mating ewe lambs at the approximate age of 1 year is likely to lead to depressed reproductive performance particularly when the summerlive weight-­loss is elevated.