Rela tionshipof puberty and semen characteristics to seasonal and nutritional variations in saidi ram lambs [electronic resource].

Includes references.

This study was designed to determine puberty and semen characteristics in Saidi ram lambs in relation to seasonal and nutritional variations. Sixteen Saidi ram lambs of 6-7 months age and average body weight 31.55 .kg were divided into four equal groups. The 1st group was served as a control (Maintenance). the 2nd group was fed a high protein/low energy ration (HL), the 3rd group wasted a low protein/high energy ration (LH) and the 4th group was fed a high protein/high energy ration (HH). Ram lambs were checked daily early in the morning for 15 minutes for observing sexual behavior by introducing a ram lamb to a teaser ewe chosen randomly from a/lock o{sheep. The ram which showed erection and extrusion of the penis out q{ the sheath was caught immediate/y and a smear of fluids secreted around the penile sheath was prepared for microscopic examination. The ram which produced sperm in the smear was immediately trained for semen collection by an artificial vagina. One ejaculate/week/ram was taken to determine semen characteristics (ejaculate volume. pH value, mass motility. sperm concentration, live & dead sperms and sperm abnormalities). Rams fed HL ration reached puberty earlier (338.3 days) than rams fed LH ration (349.0 days). rams fed HH ration (373.0 days) and rams fed LL ration (394.5 days). Significant effects (p<O.05) were found for the different levels of feeding on puberty. Quality of semen was much better in spring and autumn than in summer and winter. Furthermore, rams fed low protein and/or low energy had a poor semen quality compared to the other groups. From these data, low feeding levels are unacceptable in practice owing to increase of age at puberty and reduction of semen quality as well. So, the economic use of Saidi ram semen required collecting and utilizing semen in autumn and 10 % addition of protein and TDN over the maintenance requirements (14 % protein and 73 % TDN).

Summary in Arabic.

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