Semen quality assessment of local Katjang and cross-bred (Katjang x German) bucks

Comparative reproductive performance of Saanen and Toggenburg bucks raised under tropical environment

The objective of this study was to evaluate the effect of breed and age on scrotal measurements and semen characteristics of Saanen and Toggenburg bucks raised under extensive system in the tropic. The study was conducted using Toggenburg and Saanen bucks; the bucks were allocated into two different groups based on breed and age in 2 × 2 factorial completely randomized design. The body weight was determined using a hanging weighing scale expressed in kilogrammes (kg). Scrotal circumference and scrotal length were measured using metal measuring tape. Semen characteristics evaluated were volume, consistency, mass activity and progressive motility, live sperm cells, normal morphology and spermatozoa concentration. The current study found that breed of bucks had no influence on body weight, scrotal circumference, scrotal length, volume, mass activity, progressive motility, live sperm cells and sperm morphology. The study also found that Toggenburg bucks had higher semen consistency and spermatozoa concentration as compared with Saanen bucks. Therefore, it can be concluded that Toggenburg bucks can produce high number of total spermatozoa and as a result higher semen doses for artificial insemination purposes. Further studies with more number of animals are recommended.

Reproductive characteristics of Rayini male goats of Kerman province in Iran

An artificial vagina was used to collect semen from 14 native Iranian Rayini goats, at 15-day intervals starting on 1 July and ending on 30 December 2000. Testicular size, semen volume, sperm concentration, percent live sperm, percent normal sperm, and total number of live-normal sperm were significantly higher during the summer months. The average semen volume, percent live sperm and percent abnormal sperm during the sampling period varied between 1 and 1.4 mL, 60 and 78%, and 7 and 13%, respectively. The total number of live and normal sperm in the ejaculate during the sampling period varied from 1000 to 2500 million. Testicular size, semen volume and the total number of live and normal sperm were significantly greater in bucks weighing 55-60 kg as compared with 50-54 kg. Seminal fluid pH values were significantly lower from July to October (pH <6) than the values from November to December (pH >6.1). Lowest level of lactate dehydrogenase in the seminal fluid was recorded in early September (2.2 U/mL) and the highest level in November (2.5 U/mL). Seminal fluid K ion level increased gradually from July (52 mg/dL) to the November (97 mg/dL). Variation of seminal fluid Na ion concentration (71-74 mg/dL) was not significant during the sampling period. The correlation coefficients of total number of live-normal sperm with seminal fluid K level (r=-0.65) and LDH (r=-0.36) were negative (P<0.01). The data indicated that the semen quality and quantity of Rayini bucks were higher during summer and early autumn.