تأثير نظم الرضاعة و الفطام في العمر و الوزن عند البلوغ الجنسي و بعض الصفات التناسلية في الأغنام العواسية

الملخص EN

A flock of seventy-two Awassi ewes aged five years were used in this study to evaluate the effects of three suckling system (24, 15, 9) hours and two weaning system at the weight of (15 and 20) Kg on age, weight at puberty, scrotum circumference and size and some characteristics of semen of Awassi lambs.

Suckling and weaning systems had a significant effect (p≤0.05) on age and weight at puberty for males and the benefit of the suckling group for 24 hours and the weaning system of 20 kg.

At 5 and 6 months of age, the suckling system had a significant effect (p≤0.05) on the circumference and size of the scrotum.

At 6,7 and 8 months, the influence of the weaning system on the circumference and size of the scrotum, with the superiority of the suckling group 24 hours and the weaning system of 20 kg, a gradual and significant increase (p≤0.05) in the circumference and size of the scrotum was observed with age, and a significant improvement (p≤0.05) was observed in the characteristics of semen as the measurement period progresses.

The lambs in the 24-hour suckling group gave the best semen consistency at puberty and after 4 weeks of puberty, and the 24-hour suckling group was superior than suckling group 9 hours in individual motility of sperm at puberty, and the interaction coefficients had a significant effect on age, weight at puberty, circumference and size of the scrotum at 5,6-and 7- months of age.

The interaction between treatment effect on the size of semen in the second collection after puberty and its consistency at puberty also at the second collection the interaction had a significant effect (p≤0.05) on the individual and mass motility of the sperms at puberty and in the mass motility on the second collection of semen.

Suckling and weaning systems had no significant effect on age and weight at puberty for female except for the superiority of the second interaction treatment on the third in weight at puberty which reached 37.88 and 27.80 kg respectively.

The aim of this study was to find out the effect of suckling and weaning system for reaching sexual puberty and determining the age and weight at puberty in male and female Awassi sheep in addition to their effect on the circumference and size of the testicle and some of the semen characteristics of lambs, which are important characteristics for raising reproductive efficiency of the flock.

The study recommends following the 24-hour suckling system and 20 kg weaning system, which leads to approach male lambs at a lower age and higher weight at sexual puberty.