This experiment was designed to study the relationship between growth rate and sexual development in Najdi ram lambs. Forty-five Najdi ram lambs were used in nine age groups (1-9th month age), keeping 5 lambs in each group. Results show that mean testis size and scrotal circumference increased at a constant rate, reaching a maximum value of 392.00 ± 2.00 g and 25.00 ± 0.32 cm respectively, at the age of 9 months. A similar trend of growth was observed for the mean body weight, reaching a maximum value of 40.2 ± 0.20 kg at the age of 9 months. There was a positive correlation between the increasing rates of body weight and size of the testis. There were significant differences (P < 0.05) in testis size, scrotal circumference and body weight of lambs between all ages (1-9 months). The histological section of testis showed that a small number of mature sperms appeared in the eighth month of age and their numbers increased in the ninth month. In conclusion, the current findings indicated that puberty in Najdi rams occurs between the 8th and 9th months of age.
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http://dx.doi.org/10.1016/j.sjbs.2013.09.001 | DOI Listing |
Anim Reprod
April 2023
Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia.
There is a paucity of information with respect to group-training for artificial vagina and its influence on semen characteristics and sexual behavior of young untrained rams. A total of 18 healthy Najdi rams (with an initial body weight of 40-45 Kg and 7-8 month-old) were consequently used herein to test the usefulness of group-training for artificial vagina-mediated semen collection during the breeding season. Rams were randomly segregated into three groups ( = 6 rams per protocol), and the whole experiment was lasted for 10 weeks.
View Article and Find Full Text PDFTheriogenology
August 2020
Department of Theriogenology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, 44511, Egypt; Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia. Electronic address:
The aim of the study was to investigate the effects of different concentrations of resveratrol on head morphology, motility characteristics, oxidative state and in vitro fertility of cooled ram spermatozoa. Pooled semen from three Najdi rams was diluted with Triladyl® having different concentrations of resveratrol, zero (control), 200 μM (45.65 μg/mL) and 400 μM (91.
View Article and Find Full Text PDFTheriogenology
February 2017
Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia.
This study was carried out using 24 Najdi ram lambs of approximately 6.5 months old to evaluate the effects of feed restriction and frequency of feeding on hormone concentrations of leptin and testosterone, sexual behavior, and semen traits. Ram lambs were allotted equally into three feeding groups.
View Article and Find Full Text PDFTheriogenology
September 2015
Department of Animal production, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia.
This study was carried out using 300 multiparous Najdi ewes during breeding season to compare the effects of fluorogestone acetate (FGA) sponges and controlled internal drug release (CIDR) dispensers to synchronize estrus on reproductive performance and hormonal profiles. Ewes were equally and randomly allotted into group A (FGA) and group B (CIDR); intravaginal progestagen was administered for 14-day period with intramuscular administration of 600-IU eCG at withdrawal time. Estrus was detected using a vasectomized ram starting 12 hours after progestagen withdrawal and repeated every 12 hours up to 84 hours.
View Article and Find Full Text PDFSaudi J Biol Sci
April 2014
Department of Zoology, College of Sciences, King Saud University, Saudi Arabia.
This experiment was designed to study the relationship between growth rate and sexual development in Najdi ram lambs. Forty-five Najdi ram lambs were used in nine age groups (1-9th month age), keeping 5 lambs in each group. Results show that mean testis size and scrotal circumference increased at a constant rate, reaching a maximum value of 392.
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