Abstract:
Goat production is central to resource-poor rural livelihoods in the tropics. However, it is constrained by high
inbreeding levels and poor access to good quality breeding bucks. In this study, semen extenders differing in egg
yolk and energy level were compared in their ability to maintain liquid semen from a tropical goat breed, when
stored at physiological (37 °C) or refrigerator (4 °C) temperature. Semen was collected weekly for nine weeks
from seven bucks of the Small East African goat breed, diluted in three extenders and incubated at 37 °C or 4 °C
for 24 h. The semen parameters: viability, motility and morphology were better preserved when semen was
incubated at 4 °C compared to 37 °C across all extenders. Sperm motility after 24 h at 4 °C was 50.4 ± 5.5%,
50.4 ± 6.2% and 54.3 ± 5.4% for Extender 1 (high glucose, 18% egg yolk), Extender 2 (low glucose, 2.5% egg
yolk) and Extender 3 (low fructose, no egg yolk), respectively. Extender 2 maintained significantly higher
viability values (67.7 ± 2.5%) at 24 h compared to Extenders 3 (59.3 ± 2.1%) and 1 (46.7 ± 4.2%). Normal
morphology after 24 h (88.1 ± 3.1% at 4 °C and 85.6 ± 3.1% at 37 °C) fell within the acceptable range for
good quality semen. Acceptable quality was maintained within 8 h and up to 24 h from collection for non-frozen
goat semen stored at 37 °C and 4 °C temperature, respectively. These results imply that Small East African goat
semen diluted in low or non-egg yolk based extenders and stored at refrigerator temperature can be valuable for
artificial reproduction of native goats on low resource capacity farms in developing countries
