Characterization of seminal plasma constituents of unimproved indigenous and Tankwa goats

Abstract

The aim of the study was to characterize and compare seminal plasma constituents of unimproved indigenous and Tankwa goats. In this study, unimproved indigenous (11) and Tankwa (11) goats were used. Their average age was 3 ± 0.8 years and average bodyweights were 35.5 ± 2.1 kg and 59.8 ± 1.9 kg, respectively. Semen samples were collected with an electro ejaculator, and evaluated for macroscopic and microscopic semen characteristics and seminal plasma constituents. Both unimproved indigenous and Tankwa goats had normal semen characteristics for goats, with the exception of sperm cell concentration. However, Tankwa goats had higher straight-line velocity and average path velocity compared with unimproved indigenous goats. Unimproved indigenous goats had higher intact acrosome than Tankwa goats. Lipocalin-type prostaglandin-D synthase was one of the constituents that were detected, but it was below the detection limit of 0.5 mmol/L. Moreover, the semen of unimproved indigenous and Tankwa goats had the same levels of fertility-associated antigen, lactate dehydrogenase, sodium, potassium, magnesium, calcium, glucose, cholesterol, triglyceride, lipids and urea. In conclusion, unimproved indigenous and Tankwa goats had the same seminal plasma constituents. These constituents seem to be optimal for the sperm cells, as they resulted in acceptable semen characteristics, except for sperm cell concentration, which was low. Moreover, acceptable standards need to be set for all seminal plasma constituents, as they are not currently known.

Quantitative sperm characteristics of Tankwa goats with special reference to hyperactivated motility

“…The standard semen parameters of Tankwa goats in the current study are in the same range that was reported for South African indigenous goats (Bopape et al, 2015;Ramukhithi et al, 2018) and for Saanen, Angora, and British goat breeds (Ahmad & Noakes, 1996;Nur et al, 2005;Talebi et al, 2009). Studies on Norwegian goats (Paulenz et al, 2005) and Florida goats (Hildago et al, 2008) indicated that a highly fertile buck must produce a sperm concentration of ≥2000 x10 6 /mL.…”

“…In the present study, percentages of rapidswimming spermatozoa (12.8 ± 11.3%, range 2.6-43.1%) and normal sperm morphology (62.0 ± 26.3%) were lower than those found by Ramukhithi et al (2018) for the same Tankwa goat population (41.2 ± 5.9%; 93.7 ± 1.7%). This inconsistency is probably owing to a larger sample size, a larger variation in sperm motility and different cut-off values for swimming speed classes in the present study compared with Ramukhithi et al (2018). Moreover, CASA-derived cut-offs were used in the present study to determine percentage normal morphology, whereas Ramukhithi et al (2018) scored morphology manually.…”

“…The Tankwa goat thus falls within this range with a mean sperm concentration of 2293.7 ± 1853.6 x10 6 /mL. In the present study, percentages of rapidswimming spermatozoa (12.8 ± 11.3%, range 2.6-43.1%) and normal sperm morphology (62.0 ± 26.3%) were lower than those found by Ramukhithi et al (2018) for the same Tankwa goat population (41.2 ± 5.9%; 93.7 ± 1.7%). This inconsistency is probably owing to a larger sample size, a larger variation in sperm motility and different cut-off values for swimming speed classes in the present study compared with Ramukhithi et al (2018).…”

“…This inconsistency is probably owing to a larger sample size, a larger variation in sperm motility and different cut-off values for swimming speed classes in the present study compared with Ramukhithi et al (2018). Moreover, CASA-derived cut-offs were used in the present study to determine percentage normal morphology, whereas Ramukhithi et al (2018) scored morphology manually. A recent study, which used a similar approach to assess rat sperm morphometry and morphology reported a similar discrepancy between manually assessed normal morphology (>90%) and automated analysis (67 -74%) ( Van der Horst et al, 2018b).…”

“…Except for a study on the seminal plasma constituents of Tankwa goats (Ramukhithi et al, 2018), there is not sufficient information about the reproductive biology of these goats to select males for future breeding and smallholder farming. The purpose of this study was to provide a more detailed investigation of male fertility by employing objective and novel techniques to evaluate the semen characteristics and sperm functionality of Tankwa goats.…”