Effect of body condition and supplementary feeding on the reproductive performance of awassi ewes

الملخص EN

This study was conducted to evaluate the effect of body condition score (BCS) and supplementary feeding on the reproductive performance of Awassi ewes.

One hundred sixty Awassi ewes aged 3-5 years (Average live weight 47.41 ± 0.76) were used in a completely randomized design.

Six weeks before mating ewes were screened for their body condition score (BCS) and divided into two groups, low BCS (< 2.0) and high BCS (> 2.0) and ewes in each group were subdivided according to BCS and to non-supplemented and supplemented groups (n = 40 ewes).Therefore, the four groups were : 1.

Group (LBCN) = Low Body Condition Non-supplemented. 2.

Group (LBCS) = Low Body Condition Supplemented. 3.

Group (HBCN) = High Body Condition Non-supplemented. 4.

Group (HBCS) = High Body Condition Supplemented. All ewes received ad libitum barley straw, and (350g DM / ewe / day) whole barley grains.

The supplemented groups (groups 2 and 4) were fed Mating Feed Blocks (MFB) ad libitum.

Mature fertile Awassi rams (Three rams / group) were run with each group.

The results showed that the pre-mating, mating, and post-mating condition scores and body weights of the non-supplemented Ewes (Groups 1 and 3) are maintained throughout the trial.

Ewes offered supplementary feed the supplemented ewes (Groups 2and 4) gained in body condition score and weights, the differences were not significant.

The BCS and weights at mating for supplemented groups are 2.12, 2.64 and 46.11, 53.38 kg for groups 2 and 4 respectively.

The results showed that the reproductive performance of Awassi ewes improved considerably due initial BCS and MFB supplementation.

The percent of ewes lambed after mating during the first and second estrus cycles were significantly (P < 0.05) affected by ewes' initial BCS and MFB supplementation.

The percent of ewes lambed in first cycle were 50 %, 77 %, 72.3 % and 87 % for groups LBCN, LBCS, HBCN and HBCS respectively.

Supplementation of low BCS ewes resulted a significant (P < 0.05) improvement in conception rate (17.5 %) and lambing rate (12 %).

The results have not shown any significant of initial BCS and supplementation on twinning percentage.

The percent of barren ewes at end of the trial was higher (20 %, P < 0.05) in LBCN compared to other groups.

It can be concluded that using supplementary feed for Awassi ewes is more feasible to be used with low BCS ewes than ewes with high BCS.