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Item Estimates of lactation curve parameters for Bonsmara and Nguni cattle using the weigh-suckle-weigh technique.(South African Society for Animal Science, 2013-02-16) Maiwashe, A.; Nengovhela, N.B.; Nephawe, K.A.; Sebei, J.; Netshilema, T.; Mashaba, H.D.; Nesengani, L.; Norris, D.Milk production accounts for about 60% of the variation in weaning weight and is therefore considered an economically important trait in beef production. However, milk production data is not routinely available in beef improvement programmes and therefore weaning weight is used as a proxy for milk production. Despite the importance of milk production in beef cattle, little research has been done to evaluate the milk production potential of South African indigenous beef cattle. The objective of this study was to estimate average lactation curve parameters for the South African Bonsmara and Nguni cattle. Milk yield was estimated using the weigh-suckle-weigh technique. Lactation curves were modelled using a nonlinear form of the incomplete gamma function (Wood function): Yt = atb exp-ct. Estimates of the a, b and c parameters were 4.095 ± 0.808, 0.274 ± 0.063 and 0.005 ± 0.001 for the Bonsmara, respectively. Corresponding estimates for the Nguni were 1.869 ± 1.527, 0.451 ± 0.242 and 0.008 ± 0.003. Peak lactation time was estimated to be 59 days in Bonsmara and 54 days in Nguni. Estimates of peak yields were 10 kg and 7 kg for the Bonsmara and Nguni, respectively. Estimates of daily milk yield obtained in the current study provide useful baseline information for more accurate modelling of South African beef production systems.Item The influence of stocking density on body weight, egg weight, and feed Intake of adult broiler breeder hens.(Elsevier, 2007-04-05) Mtileni, B. J.; Nephawe, K. A.; Nesamvuni, A. E.; Benyi, K.The influence of stocking density on BW, egg weight (EW), and feed intake (FI) in Ross broiler breeder hens (n = 120) was investigated during the late medium egg production period (from 50 to 54 wk of age). Birds were randomly allocated to 6 pens in densities of 15, 20, and 25 birds/pen, giving rise to a floor space allowance of 5, 6.67, and 8.33 birds/m2, respectively. Each density was replicated twice, and the order among the 6 pens was chosen at random. Data were analyzed using the repeated measures techniques of the Statistical Analysis System, considering the covariance structure of the observed data. There was a significant effect attributable to stocking density, time (in days), and their interaction for BW, EW, and FI. Birds in density of 6.67 per m2 were lighter but had heavier eggs than birds in density of 5 per m2; however, birds in density of 8.33 per m2 had similar BW and EW with birds in the other 2 groups. The mean FI were statistically different among the 3 groups, with a reduction in FI as density increases. Total egg production within the 3 density groups and average egg production per bird were also analyzed using categorical data techniques. The results indicated that stocking density influenced egg production, with birds at higher density producing fewer eggs per bird. Although generous floor space allowances were allocated per bird in this experiment, stocking density influenced the performance of broiler breeder hens.Item The effect of herd of origin by year on post-weaning traits of young beef bulls at centralized testing centres in South Africa.(South African Society for Animal Science, 2006-01-01) Nephawe, K.A.; Maiwashe, A.; Theron, H.E.The effects of herd of origin by year on the average daily gain (ADG), average daily feed intake (DFI), shoulder height (SDH) and scrotal circumference (SCR) of beef bulls at centralized test centres in South Africa were investigated using data of Bonsmara cattle. Data consisted of post-weaning traits of beef bulls tested between 1990 and 2003, with available weaning weight (WWT) and weaning management group information as well as weaning weights of their contemporaries. A multiple-trait animal model including ADG, DFI, SDH and SCR, together with WWT was used. The model for WWT (adjusted to 205 days of age and age of dam by sex of calf classes) included the fixed effect of management group and random effects ofdirect additive genetic and dam effects, while the model for post-weaning traits included fixed effects of test group and age of the bull at the end of test (fitted as linear and quadratic regressions) and random effects of direct additive genetic and herd of origin by year (HY) effects. Variance components were estimated using REML procedures. Heritability estimates were 0.27, 0.34, 0.36, 0.51 and 0.46 for WWT, ADG, DFI, SDH and SCR, respectively. The contribution of HY effects to the phenotypic variance of ADG, DFI, SDH and SCR were 9%, 10%, 6% and 5%, respectively. Inclusion of HY effect resulted in the re-ranking of sires, with rank correlations ranging from 0.86 to 0.98 among the top sires, across traits. These results suggest that the HY effect should be included in the model for the national genetic evaluation of post-weaning traits of beef bulls measured at centralized testing centres in South Africa.Item Genetic relationships between sex-specific traits in beef cattle: Mature weight, weight adjusted for body condition score, height and body condition score of cows, and carcass traits of their steer relatives.(2003-11-03) Nephawe, K. A.; Cundiff, L. V.; Dikeman, M. E.; Crouse, J. D.; Van Vleck, L. D.Data from the first four cycles of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center (USMARC) were used to investigate genetic relationships between mature weight (MW, n = 37,710), mature weight adjusted for body condition score (AMW, n = 37,676), mature height (HT, n = 37,123), and BCS (n = 37,676) from 4- to 8-yr old cows (n = 1,800) and carcass traits (n = 4,027) measured on their crossbred paternal half-sib steers. Covariance components among traits were estimated using REML. Carcass traits were adjusted for age at slaughter. Estimates of heritability for hot carcass weight (HCWT); percentage of retail product; percentage of fat; percentage of bone; longissimus muscle area; fat thickness adjusted visually; estimated kidney, pelvic, and heart fat percentage; marbling score; Warner-Bratzler shear force; and taste panel tenderness measured on steers were moderate to high (0.26 to 0.65), suggesting that selection for carcass and meat traits could be effective. Estimates of heritability for taste panel flavor and taste panel juiciness were low and negligible (0.05 and 0.01, respectively). Estimates of heritability from cow data over all ages and seasons were high for MW, AMW, and HT (0.52, 0.57, 0.71; respectively) and relatively low for BCS (0.16). Pairwise analyses for each female mature trait with each carcass trait were done with bivariate animal models. Estimates of genetic correlations between cow mature size and carcass composition or meat quality traits, with the exception of HCWT, were relatively low. Selection for cow mature size (weight and/or height) could be effective and would not be expected to result in much, if any, correlated changes in carcass and meat composition traits. However, genetic correlations of cow traits, with the possible exception of BCS, with HCWT may be too large to ignore. Selection for steers with greater HCWT would lead to larger cows.Item Genetic parameter estimates for live animal ultrasound measures of carcass traits in South African Angus cattle.(South African Society for Animal Science, 2011-01-01) Seroba, M.M.; Maiwashe, A.; Nephawe, K.A.; Norris, D.Genetic parameters were estimated for body weight at scanning (SCW) and live animal ultrasound measures of rump fat thickness (P8FT), rib fat thickness (RBFT), rib eye-muscle area (REA) and intramuscular fat percentage (IMF) for South African Angus beef cattle. A multiple-trait animal model was used to estimate genetic parameters using the Residual Maximum Likelihood procedure (REML). Ultrasound data was used on 1 122 animals that participated in the South African National Beef Cattle Improvement Scheme. The fixed effects that were significant included contemporary group, sex and age of the animal at scanning. Random effects considered were the direct additive genetic effect and the residual. Heritability estimates were 0.38 ± 0.08, 0.34 ± 0.06, 0.33 ± 0.05, 0.32 ± 0.06 and 0.38 ± 0.06 for SCW, P8FT, RBFT, REA and IMF respectively. Genetic correlation between SCW and REA was high (0.79 ± 0.07). Genetic correlations with SCW were 0.24 ± 0.14 for P8FT, 0.25 ± 0.12 for RBFT and 0.29 ± 0.11 for IMF. Measures of body fat were genetically highly correlated with one another, with correlations ranging from 0.71 to 0.99. The magnitude of heritability estimates obtained in the current study indicates that genetic improvement for ultrasound indicators of carcass traits should be effective. However, the indirect selection of carcass traits using ultrasound data, should consider the antagonistic genetic relationship between subcutaneous and intramuscular fat.Item Genetic analysis of body weights of individually fed beef bulls in South Africa using random regression models.(FUNPEC-RP, 2011-07-07) Selapa, N.W.; Nephawe, K.A.; Maiwashe, A.; Norris, D.The aim of this study was to estimate genetic parameters for body weights of individually fed beef bulls measured at centralized testing stations in South Africa using random regression models. Weekly body weights of Bonsmara bulls (N = 2919) tested between 1999 and 2003 were available for the analyses. The model included a fixed regression of the body weights on fourth-order orthogonal Legendre polynomials of the actual days on test (7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, and 84) for starting age and contemporary group effects. Random regressions on fourth-order orthogonal Legendre polynomials of the actual days on test were included for additive genetic effects and additional uncorrelated random effects of the weaning-herd-year and the permanent environment of the animal. Residual effects were assumed to be independently distributed with heterogeneous variance for each test day. Variance ratios for additive genetic, permanent environment and weaning-herd-year for weekly body weights at different test days ranged from 0.26 to 0.29, 0.37 to 0.44 and 0.26 to 0.34, respectively. The weaning-herd-year was found to have a significant effect on the variation of body weights of bulls despite a 28-day adjustment period. Genetic correlations amongst body weights at different test days were high, ranging from 0.89 to 1.00. Heritability estimates were comparable to literature using multivariate models. Therefore, random regression model could be applied in the genetic evaluation of body weight of individually fed beef bulls in South Africa.Item Relationship between linear type and fertility traits in Nguni cows.(Elsevier, 2014-11-28) Zindove, T. J.; Chimonyo, M.; Nephawe, K. A.The objective of the study was to assess the dimensionality of seven linear traits (body condition score, body stature, body length, heart girth, navel height, body depth and flank circumference) in Nguni cows using factor analysis and indicate the relationship between the extracted latent variables and calving interval (CI) and age at first calving (AFC). The traits were measured between December 2012 and November 2013 on 1559 Nguni cows kept under thornveld, succulent karoo, grassland and bushveld vegetation types. Low partial correlations (−0.04 to 0.51), high Kaiser statistic for measure of sampling adequacy scores and significance of the Bartlett sphericity test (P< 0.01) showed that there were significant phenotypic correlations between the linear traits and the data were suitable for factor analysis. Two factors had eigenvalues >1. Factor 1 included body condition score, body depth, flank circumference and heart girth and represented body capacity of cows. Factor 2 included body length, body stature and navel height and represented frame size of cows. CI and AFC decreased linearly with increase of factor 1. There was a quadratic increase in AFC as factor 2 increased (P< 0.05). It was concluded that the linear type traits under study can be grouped into two distinct factors, one linked to body capacity and the other to the frame size of the cows. Small-framed cows with large body capacities have shorter CI and AFC.Item Genetic parameters for tick counts across months for different tick species and anatomical locations in South African Nguni cattle.(Springer, 2017-05-15) Mapholi, N.O.; Maiwashe, A.; Matika, O.; Riggio, V.; Banga, C.; MacNeil, M.D.; Muchenje, V.; Nephawe, K.; Dzama, K.The objective of the study was to characterise genetic parameters across months for different tick species and anatomical locations in South African Nguni cattle. Tick counts were conducted monthly, over a 2-year period, on 586 Nguni cattle under natural infestation, from four herds located in different provinces of South Africa. The counts were recorded for six species of ticks (Amblyomma hebraeum, Rhipicephalus evertsievertsi, Rhipicephalus decoleratus and microplus (Boofilids), Rhipicephalus appendiculatus, Rhipicephalus simus and Hyalomma marginatum) attached on eight anatomical locations on the animals and were summed by species and anatomic allocation. Heritability estimates, phenotypic and genetic correlations were estimated on a monthly basis using mixed linear models, fitting univariate and bivariate sire models. Fixed effects considered were location, sex, year and age as a covariate. Tick counts were higher in the hot months, and A. hebraeum was the most dominant tick species. Heritability estimates for tick count varied by month and trait and ranged from 0 to 0.89. Genetic correlations were mostly positive, and low to high, with some negative correlations with high standard error. Phenotypic correlations were low to moderate. In general, high genetic correlations were observed between whole body count and the anatomical location counts, suggesting that it may not be necessary to conduct whole body counts. Counts from the belly and perineumappeared to be the most suitable surrogate traits for whole body count. These findings provide useful information for developing strategies for the practical implementation of genetic selection, as a supplement to the traditional tick control measures.Item Genetic relationship between weaning weight and milk yield in Nguni cattle.(Elsevier, 2017-05-23) Nesengani, L. T.; Nephawe, K. A.; Sebei, J.; Norris, D.; Maiwashe, A.A study was conducted to estimate the genetic relationship between weaning weight and milk yield in Nguni cattle. Milk yield data (n = 125) were collected from 116 Nguni cows from Mara Research Station located in Limpopo Province and Loskop South Farm located in Mpumalanga Province using the weigh-suckle-weigh technique. Weaning weight data (n = 19 065) were obtained from stud Nguni cattle from 146 herds distributed throughout South Africa. Estimates of (co)variance components for milk yield and weaning weight were calculated using PEST and VCE softwares. The average weaning weight, age of the calf at weaning and 24-h milk yield was 158.94 kg, 210 days and 5.25 kg/day, respectively. Heritability estimates for milk yield, direct and maternal weaning weight were 0.22 ± 0.238, 0.47 ± 0.039 and 0.25 ± 0.029, respectively. Estimates of genetic correlations for milk yield and maternal weaning weight, milk yield and direct weaning weight, direct and maternal weaning weight were 0.97 ± 0.063, −0.71 ± 0.416 and −0.56 ± 0.247, respectively. The results indicate that maternal weaning weight is genetically highly predictive of milk yield in Nguni cattle. Maternal breeding values for weaning weight could therefore be used as a selection criterion to improve milk yield in Nguni cattle.Item Oestrous synchronisation and pregnancy rate following artificial insemination (AI) in South African indigenous goats.(Taylor and Francis Group, 2012-02-14) Ramukhithi, Fhulufhelo Vincent; Nedambale, Tshimangadzo Lucky; Sutherland, Ben; Greyling, Johannes Petrus Carl; Lehloenya, Khoboso ChristinaThe study evaluated the effect of duration of progestagen treatment and breed on response to oestrous synchronisation and pregnancy rate following AI in 47 Boer and 27 unimproved indigenous goats. Each breed was subdivided into two groups, based on the duration of progestagen treatment. In the long-term progestagen treatment, controlled internal drug release dispensers (CIDRs) were inserted for 16 days, while in the short-term progestagen treatment, CIDRs were inserted for 9 days. Oestrous detection was performed for a period of 72h, starting at CIDRs withdrawal. AI was performed 48 h following CIDRs removal with raw or frozen/thawed semen. Pregnancy diagnosis was performed at day 35 following AI. Boer goat exhibited a significantly (p B0.05) higher oestrous response (100%) than unimproved indigenous goats (88.9%). Breed had no effect on the onset of oestrus. Boer goat does recorded a longer duration of the induced oestrous period, compared to the unimproved indigenous goats. No significant difference was observed between short or long-term progestagen, with respect to the oestrous response, onset and duration of the induced oestrous period. The pregnancy rate was not affected by breed and semen cryopreservation. However, long-term progestagen treatment drastically reduced pregnancy rate. In conclusion, breed had an effect on oestrous response and the duration of induced oestrous period. The interaction of breed and duration of progestagen treatment had no effect on response to oestrus and onset of oestrus. The pregnancy rates of the current study were generally low and were affected by the duration of progestagen treatment.Item Comparison of different extenders and storage temperature on the sperm motility characteristics of Kolbroek pig semen.(South African Society for Animal Science, 2012-01-01) Mapeka, M.H.; Lehloenya, K.C.; Nedambale, T.L.Maintaining a successful pig artificial insemination programme depends on a number of factors, including evaluation of semen characteristics. This study compared the efficacy of different extenders on the sperm motility of Kolbroek semen during short term storage at 4 °C and 25 °C. Semen was collected from Kolbroek boars using the gloved hand technique and transported to the laboratory for evaluation. Semen was pooled and randomly allocated to four groups and diluted at a ratio of 1:1 (v/v) with Beltsville thawing solution (BTS), Kobidil+, egg yolk citrate (EYC) and non-extended semen (Control). Each extender had two similar semen samples, making a total of eight samples. Extended and non-extended semen were stored at 4°C and the other samples at 25 °C for 1 h. Data were analyzed using analysis of variance (ANOVA). The total sperm motility of semen stored at 25 °C was higher when semen was extended with BTS and Kobidil+ in comparison to the egg yolk citrate diluent. However, total sperm motility in the non-extended semen did not differ from the BTS and EYC group during storage at 25 °C. Sperm progressive motility was higher in the BTS group, compared to the Kobidil+ and non-extended groups. Sperm motility of Kolbroek semen at 4 °C did not differ between all extender treatments. Total motility rate was significantly higher when Kolbroek sperm were stored at 25 °C than at 4 °C. It can be concluded that Kolbroek sperm, extended with BTS, maintained their motility rate better for short term storage at 25 °C in comparison to 4 °C.Item Comparative study on semen characteristics of Kolbroek and Large White boars following computer aided sperm analysis.(Academic Journals, 2011-09-09) Masenya, Matshidiso Bailekae; Mphaphathi, M. L.; Mapeka, M. H.; Munyai, P. H.; Makhafola, M. B.; Ramukhithi, F. V.; Malusi, P. P.; Umesiobi, D. O.; Nedambale, T. L.Consistent estimates of boar fertility potential from objective semen evaluation could be a valuable tool for boar selection. The objective of this study was to evaluate semen characteristics of Kolbroek and Large White boars following computer aided sperm analysis® (CASA). Eight ejaculates were collected separately from individual Kolbroek (n = 4) and Large White (n = 4) boars using the gloved-hand technique. Following semen collection, semen was evaluated for macroscopic and microscopic characteristics. Analysis of variance (ANOVA) was used to test the differences between the breeds (P<0.05). The bodyweight of Kolbroek (154.7 ± 8.5) was significantly lower compared to Large White (189.9 ± 7.7) boar. There was also a positive correlation between bodyweight and semen volume of both Kolbroek (r = 0.2197) and Large White (r = 0.2577) boar. However, no significant differences were observed in Kolbroek and Large White boar semen volume (140 and 170 ml), sperm concentration (0.727 and 0.761 × 109 sperm cell/ml), pH (7.0 and 7.0), total motility (95 and 91%) and morphology (84 and 82%). In conclusion, the bodyweight of Kolbroek and Large White boar was positively correlated with ejaculated semen volume. Sperm characteristics of both Kolbroek and Large White boar were similar. Sperm class analyser® provided a precise and more objective information of sperm motility characteristics.Item Effects of silage sealing films on fermentation dynamics of ensiled maize and nutrient utilization by Damara rams.(South African Society for Animal Science, 2019-11-22) Ndleleni, N.W.; Malebana, I.M.M.; Du Toit, C.J.L.; Nephawe, K.A.; Meeske, R.; Nkosi, B.D.An experiment was conducted to evaluate the effects of two silage sealing films on whole crop maize (WCM) fermentation, aerobic stability and nutrient digestion by rams. Prior to ensiling (day 0), triplicate samples of the WCM were collected to determine dry matter, pH, water-soluble carbohydrates (WSC), lactic acid (LA) bacterial counts and nutrient concentration. A single bunker silo was divided into eight sections that were ensiled using either a standard polyethylene film (PE) or an orange oxygen barrier (OB) Silostop film for 180 days. After 180 days of ensiling, six silage samples were collected from each replicate. Three samples were used for nutrient analysis and the other three to determine aerobic stability. Sixteen four-year-old Damara rams with an average live weight of ± 54 kg were housed individually in wooden pens (2.2 m2) to determine digestibility of nutrient in the silage. The digestibility study was conducted as a switchover design with four feeding phases. The silage was supplemented daily with 1% urea and fed to the rams ad libitum. Nutritional value of the silage was not (P >0.05) affected by the ensiling films. The OB-ensiled maize had higher (P <0.05) LA, lower pH, CO2 production and yeast and mould populations, and lower WSC compared with the PE-ensiled maize. Dry matter intake, nutrient digestion and nitrogen balance of rams fed the silage were not affected (P >0.05) by treatments. The OB film improved the fermentation and aerobic stability of WCM silage but did not influence its nutrient utilization by rams.Item Developmental potential of vitrified holstein cattle embryos fertilized In Vitro with sex-sorted sperm.(American Dairy Science Association, 2006-02-15) Xu, J.; Guo, Z.; Su, L.; Nedambale, T. L.; Zhang, J.; Schenk, J.; Moreno, J. F.; Dinnyes, A.; Ji, W.; Tian, X. C.; Yang, X.; Du, F.In vitro fertilization (IVF) is a feasible way to utilize sex-sorted sperm to produce offspring of a predetermined sex in the livestock industry. The objective of the present study was to examine the effects of various factors on bovine IVF and to systematically improve the efficiency of IVF production using sex-sorted sperm. Both bulls and sorting contributed to the variability among differential development rates of embryos fertilized by sexed sperm. Increased sorting pressures (275.8 to 344.75 kPa) did not have a significant effect on the in vitro fertility of the sorted sperm; neither did an extended period of 9 to 14 h from semen collection to sorting. As few as 600 sorted sperm were used to fertilize an oocyte, resulting in blastocyst development of 33.2%. Postwarming of vitrified sexed IVF embryos resulted in high morphological survival (96.3%) and hatching (84.4%) rates, similar to those fertilized by nonsexed sperm (93.1 and 80.6%, respectively). A 40.9% pregnancy rate was established following the transfer of 3,627 vitrified, sexed embryos into synchronized recipients. This was not different from the rates with nonsexed IVF (41.9%, n = 481), or in vivo produced (53.1%, n = 192) embryos. Of 458 calves born, 442 (96.5%) were female and 99.6% appeared normal. These technologies (sperm sexing-IVF-vitrification-embryo transfer) provide farmers, as well as the livestock industry, with a valuable option for herd expansion and heifer replacement programs. In summary, calves were produced using embryos fertilized by sex-sorted sperm in vitro and cryopreserved by rapid cooling vitrification.Item Assessing and mapping water-energy-food nexus smart innovations and practices in Vhembe District Municipality, Limpopo Province, South Africa.(Frontiers Media, 2024-01-17) Musetsho, Khangwelo D.; Mwendera, Emmanuel; Madzivhandila, Tshilidzi; Makungo, Rachel; Volenzo, Tom E.; Mamphweli, Ntshengedzeni S.; Nephawe, Khathutshelo A.Water, energy, and food and their interactions (commonly referred to as the WEF nexus) are critical pillars to resolving the intractable global challenges such as poverty, hunger, malnutrition, poor sanitation, climate, and health crises. The nexus approach, practices, and innovations at the household level are critical determinants of whether resource use efficiency, co-benefits, basic rights to water and food, and sustainability governance are attained. In particular, smart WEF innovations can contribute to the current generations’ economic, social, and environmental needs without compromising the needs of the future generation. The study aimed to identify smart innovations, practices, and factors influencing their adoption to inform policy and decision-making processes. The study intends to support scaling up the adoption of innovations and practices that enhance sustainability and resource security in support of the sustainable development goals (SDGs). Semi-structured interviews and key informant interviews (KII) supplemented with observational checklists were used to identify the WEF nexus smart technologies, innovations, and practices in Vhembe District Municipality, Limpopo Province, South Africa. Data were collected from a sample size of 128 households in the study area. Our findings revealed synergistic smart innovation practices across WEF resource use and management practices. Though indigenous knowledge (IK) practices were widely evident in the study area, non-existent WEF smart knowledge support systems existed in the study area. Indigenous knowledge practices were the most elicited innovation by 99.2% of households, suggesting it is critical to advancing WEF smart innovations and practices and needs to be integrated into any policy and governance interventions. A proportion of households recycle water (27%), whilst 53% use untreated water. Furthermore, the knowledge systems on smart WEF innovations were fragmented despite their potential to synergize sustainability objectives. Exploring innovation platforms (IPs) as vehicles for dissemination, innovation, and extension and advisory service delivery, as well as validation of Indigenous Knowledge Systems (IKS), has the potential to contribute to the diffusion, uptake, and scaling of existing innovation and practices with significant spill-over effects on WEF resource security and sustainability outcomes both at local and extra local scales.Item Viability of bull semen extended with commercial semen extender and two culture media stored at 24 °C.(South African Society for Animal Science., 2016-12-13) Raseona, A.M.; Ajao, O.A.; Madzhie, L.R; Nedambale, T.L.; Barry, D.M.The aim of this study was to evaluate the viability of bull spermatozoa diluted with commercial semen extender and two culture media stored at controlled room temperature (24 °C) for 72 hours. Two Nguni bulls were used for semen collection with the aid of an electro-ejaculator. After macroscopic evaluation, semen was pooled and aliquoted randomly into Triladyl, modified Ham’s F10, and TCM-199 culture media, and then stored at 24 °C. Sperm motility parameters, morphology, and viability were analysed with computer aided sperm analysis (CASA) after 0, 24, 48 and 72 hours. The study was replicated four times, and data were analysed using analysis of variance (ANOVA). Triladyl had significantly higher sperm viability rate (41.3%) and total motility rate (96.3%) for 72 hours than modified Ham’s F10 (86.8%; 26.5%) and TCM-199 (76.7%; 25.0%) culture media. Ham’s F10 had higher progressive motility rate (37.8%) than the other extendersTCM-199 (31.7%) and Triladyl (23.4%). There was no significant difference in viability rate between Ham’s F10 (26.5%) and TCM-199 (25.0 %) after 72 hours’ storage at 24 °C. Furthermore, no significant difference was observed in total sperm abnormalities, except for reacted acrosomes and absent tails, between the two Nguni bulls. Nguni semen can be preserved in Triladyl or modified Ham’s F10 and TCM-199 culture media, stored at 24 °C, and stay viable for 72 hours.Item The effect of environmental factors and husbandry practices on stress in goats.(Elsevier, 2016-06-09) Kruger, L.P.; Nedambale, T.L.; Scholtz, M.M.; Webb, E.C.Routine handling procedures used in the management of a flock are not generally regarded as stressful and have not been extensively researched. The aim of this study was to determine the serum cortisol concentration after routine handling procedures, viz. handling, heat exposure, food deprivation and water deprivation as well as the cumulative effect of these potential stressors in South African indigenous goats. The results indicated that goats subjected to typical routine handling procedures such as oral drenching and subcutaneous vaccination had significantly higher serum cortisol concentration than the basal levels and can be considered as acute stressors. Stressors that did not involve handling, such as heat exposure, food and water deprivation did not elicit cortisol levels significantly higher than the basal level in this study.Item Comparison of four different permitting and combination of two best cryoprotectants on freezing Nguni sperm evaluated with the aid of computer aided sperm analysis.(Elsevier, 2016-04-04) Seshoka, Mokgadi Magdelin; Mphaphathi, Masindi L.; Nedambale, Tshimangadzo L.Cryopreservation has been reported to damage approximately 40e50% of viable sperm in bull semen. The present study was undertaken to assess the cryo-effectiveness of glycerol (GLY), ethylene glycol (EG), dimethyl sulfoxide (DMSO) and propylene glycol (PND) as cryoprotectant during the cryopreservation of Nguni bull semen. Semen was collected from 18 Nguni bulls and evaluated macroscopically and microscopically for sperm parameters. Thereafter, the semen samples were diluted with egg-yolk citrate extender supplemented with either 12% GLY or DMSO or EG or PND cryoprotectant. Semen samples were loaded into straws and placed into a controlled rate programmable freezer and stored in a liquid nitrogen tank. Following semen thawing, artificial insemination (AI) was done on synchronized Nguni cows. The in vitro fertilization (IVF) was conducted on cow's oocytes to test the fertilizing ability. Data was analyzed with the aid of ANOVA. A significant difference (p < 0.05) was recorded between fresh total sperm motility rate (94.7 ± 2.6%) and frozen-thawed sperm total motility rate with GLY (77.8 ± 11.0%), EG (20.4 ± 10.1%), DMSO (15.7 ± 11.9%) and PND (11.2 ± 11.3%). Interestingly, a positive correlation between total sperm motility and pregnancy rate (r ¼ 0.42) was recorded. However, a negative correlation of Nguni sperm parameters with IVF (r ¼ -0.53) was obtained. The freezing-thawing process did reduce the Nguni sperm total sperm motility percentage.Item The characterisation and cryopreservation of Venda chicken semen.(Elsevier, 2016-01-18) Mphaphathi, Masindi L.; Seshoka, Mokgadi M.; Luseba, Dibungi; Sutherland, Benjamin; Nedambale, Tshimangadzo L.Objective: To characterize Venda cocks semen, find a suitable short-term diluted semen storage temperature, find a suitable cryopreservation cryoprotectant and to investigate cryoprotectant toxicity. Methods: Semen was collected from six Venda cocks and evaluated macroscopically for semen volume, pH and sperm concentration. Microscopic sperm characteristics examined included were total motility (rapid, medium and slow) progressive and non-progressive motility. Velocity characteristics included curvilinear and straight-line velocity, average path velocity, linearity, straightness, wobble, amplitude of lateral head displacement and beat cross frequency. Results: Results showed that the average semen volume was 0.3 ± 0.1 mL, the pH6.9 ± 0.4 and the sperm concentration (6.8 ± 79.8) × 109/mL. A positive correlation was observed between body weight and semen volume (r = 0.38). Similarly a significant difference between the initial sperm total motility (TM%) of 87.5 ± 8.6 and samples stored for 24 h at 5 degree C (55.0 ± 8.0) and 25 degree C (30.6 ± 6.1) was recorded. The percentage live and normal sperm was 87.0% and 93.5% (P < 0.05) respectively. The TM% recorded was significantly different in samples supplemented with DMSO (46.0 ± 8.3), ethylene glycol (EG) (45.0 ± 12.2) and propanediol (PND) (21.8 ± 10.4), following thawing. Detailed velocity values showed consistent differences between the raw and cryoprotectant-free semen samples. Conclusions: In conclusion, the Venda cock semen was subsequently found to have a higher TM% when stored in vitro at 5 degree C. DMSO and EG were found to be suitable for the cryopreservation of Venda cock semen.Item Effects of various concentrations of gonadotropins and 17β estradiol on the in vitro maturation of cattle oocytes selected using brilliant cresyl blue staining.(South African Society for Animal Science., 2016-08-02) Lekola, K.P.M.; Ng’ambi, J.W.; Nkadimeng, M.; Mphaphathi, M.L.; Nedambale, T.L.The objective of this study was to determine the in vitro maturation rate of cattle oocytes selected with brilliant cresyl blue (BCB) stain, in tissue culture medium 199 (TCM 199) supplemented with various concentrations of hormones. Oocytes were retrieved from abattoir-derived ovaries by aspiration. Oocytes were then exposed to 26 µM BCB stain, and classified according to the colour of their cytoplasm: BCB+ (oocytes with blue cytoplasm) and BCB- (unstained oocytes). The BCB selected and the non-selected immature oocytes were randomly allocated into TCM 199 + 10% foetal bovine serum (FBS) maturation media supplemented with three concentrations of hormones as treatments (T). The T1 group was matured in the presence of 0.5 µg follicle stimulating hormone (FSH)/mL, 5 mg luteinising hormone (LH)/mL and 2 µgestradiol (E2)/mL. The T2 group was matured in 1 µg FSH, 6 mg LH and 2.5 µg E2/mL. The T3 group was matured in 1.5 µg FSH, 7 mg LH and 4.5 µg E2/mL. The maturation rate of oocytes was determined by the protrusion of the first polar bodies 24 h after maturation. Data were analysed by ANOVA using SAS. Treatment 2 yielded higher maturation rates for with BCB+ (30.5%) and without BCB (35%) oocytes, with T1 giving a lower maturation rate for BCB+ (10.7%) and without BCB (9.7%) oocytes. However, BCB- oocytes had lower polar body extrusion (0.7%, 1% and 2.7%) for T1, T2 and T3, respectively. In conclusion, immature oocytes that were exposed to BCB+ and cultured in TCM 199 supplemented with 10% FBS, 1 µg FSH, 6 mg LH and 2.5 µg E2/mL had a higher number of matured oocytes (extrusion of first polar body), similar to those that were not exposed to BCB (no BCB). Oocyte selection with BCB staining was a useful test for classifying good-quality cattle oocytes.