Moulla Farid, El-Bouyahiaoui Rachid, Nazih Rebouh, Abdelaziz Norezzine, Zerrouki Nacera, Iguer-Ouada Mokrane
National Institute for Agronomic Research of Algeria (INRAA), 02, Av. Frères Ouaddek, BP, 200, El Harrach, Alger, Algeria.
Department of Agronomic, Faculty of Biologic and Agronomic Sciences, University Mouloud Mammeri of Tizi-ouzou, Tizi-ouzou, Algeria.
Vet World. 2018 Jul;11(7):889-894. doi: 10.14202/vetworld.2018.889-894. Epub 2018 Jul 2.
The aim of the present study was to define the onset of puberty in Tazegzawt ram lambs, an Algerian sheep breed in endangered status with a small population in its local area.
Body growth (body weight and thoracic perimeter), scrotal circumference (SC), penis development stages, and seminal parameters (volume, concentration, and motility) were measured. Data were recorded at fortnightly intervals in 10 animals from 9 to 49 weeks of age.
On the basis of seminal analyses, puberty occurred between 29 and 45 weeks of age. At 29 weeks of age, 30% of lambs reached puberty, and at 45 weeks of age, puberty was observed in 100% of the analyzed animals. Body weight appeared as the most determinant factor, and the onset of puberty was observed when animals reached 43.2±6.4 kg body weight with 25.8±3.7 cm of SC. Seminal analyses revealed that all parameters increased regularly from puberty onset except for sperm concentration. The mean semen volume during the study period was 0.48±0.33 mL with 0.84±0.6 mL at 37 weeks of age. Sperm concentration evolved similarly as semen volume; at 29 and 43 weeks of age, the sperm concentration was 942×10 and 1904×10 spermatozoa/mL, respectively. Kinematic parameters including the percentage of motility, the percentage of progressive motility, and gametes velocities as determined by Computer-Aided Sperm Analyzer showed the highest values at 49 weeks of age.
The current results revealed that, in Tazegzawt ram lambs, puberty occurs between 29 and 45 weeks when animals reach 43.2±4.6 kg body weight.
本研究的目的是确定塔泽格扎乌特公羊羔羊青春期的开始时间，该品种是阿尔及利亚的一种绵羊，处于濒危状态，当地种群数量较少。
测量了身体生长指标（体重和胸围）、阴囊周长（SC）、阴茎发育阶段和精液参数（体积、浓度和活力）。在9至49周龄的10只动物中，每两周记录一次数据。
根据精液分析，青春期发生在29至45周龄之间。在29周龄时，30%的羔羊达到青春期，在45周龄时，100%的分析动物出现青春期。体重似乎是最具决定性的因素，当动物体重达到43.2±6.4千克且阴囊周长为25.8±3.7厘米时，观察到青春期开始。精液分析显示，除精子浓度外，所有参数从青春期开始均呈规律性增加。研究期间精液平均体积为0.48±0.33毫升，37周龄时为0.84±0.6毫升。精子浓度的变化与精液体积相似；在29周龄和43周龄时，精子浓度分别为942×10⁶和1904×10⁶个精子/毫升。通过计算机辅助精子分析仪测定的运动学参数，包括活力百分比、前向运动百分比和配子速度，在49周龄时显示出最高值。
目前的结果表明，在塔泽格扎乌特公羊羔羊中，青春期发生在29至45周龄，此时动物体重达到43.2±4.6千克。
