Spermogram of Bicolor Peul and Touareg Rams: Genetic Type and Seasonal Influence

Abstract

A study on the morphological parameters of ram sperm was carried out in an experimental station in Niger during three years. Six bicolor Peul rams and five Touareg rams were used. Sperm from each ram was collected after two consecutive ejaculations once a month with an artificial vagina. Means (± SE) of the various parameters studied in Peul and Touareg rams were, respectively: live weight 47.75 ± 3.75 kg and 49.98 ± 2.99 kg; sperm volume 1.73 ± 0.36 ml and 1.78 ± 0.33 ml; sperm gross motility 4 ± 0.61 and 3 ± 0.49; spermatozoon concentration 4265 x 106 ± 762 x 106 spz/ml and 4953 x 106 ± 583 x 106 spz/ml; total number of spermatozoa 7469 x 106 ± 2382 x 106 spz and 8877 x 106 ± 2323 x 106 spz; percentage of dead spermatozoa 12 ± 10% and 19 ± 19%; percentage of abnormal spermatozoa 13 ± 12% and 17 ± 11%. The mean weight of Touareg rams was significantly higher (p < 0.05) than that of Peuls. The dry cool season significantly (p < 0.05) and negatively affected the live weights of both breeds. Mean volumes of ejaculated sperm were not significantly (p < 0.05) different between the two breeds, except during the months of July and August. Significant (p < 0.05) differences were found between the two breeds with regard to the other parameters studied. Peul rams appeared more sensitive to Sahelian climate variations than Touaregs. Under the experimental conditions of the study (i.e. in station and under good management), ram fertility of both breeds was maintained in line with the established norms throughout the year, thus suggesting that rams might be mated with ewes year-round. Further studies would help determine the impact of traditional breeding conditions, season, individual characteristics on male and female fertility parameters, and consequently on the flock size.

Keywords

• Ovin
• Mouton Peul
• Mouton Touareg
• Sperme
• Fertilité
• Niger