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. _______________________________________________________________________________________

The present study was conducted to assess boar sperm susceptibility to oxidative stress generated by hydrogen peroxide (H 2 O 2). Semen was collected in replicates from three experimental large white boars using the gloved-hand technique. Semen ejaculates from three boars were treated with different concentrations of H 2 O 2 for three hours. SYBR-14 and Propidium Iodide (PI) Live/ Dead assay kit was used to determine cell viability, and Yo-pro-1 and PI apoptosis kit was used to determine cell death, namely, apoptosis. Boar sperm motility obtained using computer aided sperm analysis (CASA) was between 90% and 100% with more than 98% viability with 0% apoptotic cells. In H 2 O 2 treated boar sperm cells, rapid (RAP) and progressive motility (PM) increased. Also, H 2 O 2 treatment induced a high positive correlation with apoptosis but high negative correlation with viability. Hydrogen peroxide decreased boar semen total motility (TM) by 10%. In addition, most of the boar sperm cells became apoptotic and lost 55% of viability under oxidative stress induced by H 2 O 2. This study illustrated that boar semen was more susceptible to oxidative stress induced by H 2 O 2 .

The objectives of the current study were to evaluate the estrous response and pregnancy rate following timed artificial insemination (TAI) with frozen-thawed semen in cows. The study was carried out in cows at different villages of KwaZulu-Natal (KZN; n = 160) and Limpopo provinces (L; n = 171). Cows were selected randomly as presented by the farmers, regardless of parity, age, breed and body weight following pregnancy diagnosis. The cows were grouped according to breed type and body condition score (BCS) on a scale of 1-5. Selected cows were inserted a controlled intravaginal drug release (CIDR ®) and removed on day 8, followed by administration of prostaglandin. Heat was observed on day 9 with the aid of heat mount detectors (HMD) that were placed on the individual cow's tail head. Cows on heat were then inseminated twice at 12 hours interval. Pregnancy diagnosis was performed by an ultra-sound scanner and rectal palpation 90 days after TAI. Data were analyzed using SAS 2006. Estrous responses were 100% in KZN and 99% in Limpopo.

Semen processing and manipulation generally result in loss of sperm motility and sperm velocity due in part to oxidative stress. In this study we investigated the vulnerability of South African indigenous unimproved buck semen to oxidative stress induced by an oxidative stress inducing agent, namely, hydrogen peroxide (H 2 O 2). Semen ejaculates were collected from four superior South African indigenous unimproved bucks in a total of ten collections and then each duplicate was treated with different concentrations of H 2 O 2 in presence or absence of Dithiothreitol (DTT). Sperm motility and velocities were determined using the computer aided sperm class analyser (CASA). SYBR-14 and propidium iodide (PI) Live/Dead assay kit was used to determine cell viability and Yo-Pro-1 plus PI Apoptosis kit was used to determine apoptosis. Statistical analysis was performed on the data using SPSS version 17.0 for Windows (SPSS Inc., Chicago, IL). South African indigenous unimproved buck raw semen motility was between 97% with 98% viability and 0% apoptotic cells. Comparisons of the untreated controls at 0 and 3 hrs incubations revealed that after 3 hrs there was overall a decrease in the number viable cells with the majority of remaining cells exhibiting circular movements accompanied by high progressive (PM) and rapid (RAP) motilities. In treated South African indigenous unimproved buck semen, H 2 O 2 marginally increased total motility (TM) with few apoptotic sperm cells while retaining high viability. Also, H 2 O 2 increased straight line distances travelled of more than 4 fold as compared to untreated controls with no circularly moving cells. Moreover, inclusion of DTT, an antioxidant, had minimal effects on TM, RAP, curvilinear velocity (VCL), straight line velocity (VSL), linearity (LIN)

In South Africa, assisted reproductive technologies (ART) such as oestrus synchronization and AI in cattle have traditionally been applied in commercial production systems but not communal production systems because of several challenges such as infrastructure and cost. The study was designed to assess factors affecting response to oestrus synchronization, conception, and calving rate of organised communal cows following timed AI in Limpopo province, South Africa. A total of 140 cows were selected from organised communal villages and categorized according to body condition score (BCS), parity, age, frame size (small to medium) and breed type (Nguni, Bonsmara, and Brahman). A 9-day CIDR® (Pfizer Laboratories, New York, NY, USA) protocol was used to synchronize the selected cows. Heat mount detectors (Karma®; Four Lakes) were used to assess oestrous synchronisation responce. The AI was done twice at 36 and 48 h post-CIDR® removal using Nguni frozen–thawed semen. Pregnancy diagnosis was performed 90 days following AI using ultrasound scanner and trans-rectal palpation. Data on influence of factors such as BCS, parity, age, district, breed type, and frame size on oestrus response, conception and calving rate were analysed using logistic regression procedure of SAS. Of 140 cows synchronized, 75% (105/140) had tripped patches and underwent AI, 41% (43/105) conceived, and 36% (38/105) calved. Parity, age, breed type, and frame size did not significantly affect oestrous synchronisation response, conception, and calving rate. However, BCS significantly (P = 0.0042) affected calving rate, whereby cows in BCS of >3 had a greater probability of success than those with BCS ≤3. Small-framed Nguni and Bonsmara type cows in their first parity with a BCS ≥3 had greater odds of conceiving following timed AI. Noteworthy, calving rate in the current study was comparable to other studies under communal areas (South African Vet. Assoc. 2004 75, 30-36; Appl. Anim. Husb. Rural Develop. 2013 6, 48-54). Therefore, the current study demonstrated an opportunity to improve the production of organised communal cattle using superior sire germplasm though assisted reproductive technologies. Cows in organised communal areas have greater probability of conceiving and calving when their condition score is >3, regardless of their age, parity, size, or breed type. It is concluded, therefore, that AI technology should be applied in cows of organised communal farmers to facilitate dissemination and propagation of superior germplasm.