Khoboso Lehloenya

University of Zululand | uzulu · Department of Agriculture

We investigated the supplementation effects of Acacia mearnsii tannin extract (TE) and encapsulated tannin extract (ETE) on reproductive performance and oxidative status of South African Mutton Merino rams. We also observed the season effect on the testicular measurements. Thirty rams were divided into five groups: 0.0 g TE (control), 1.5 g TE, 3 g...

The study was aimed to evaluate the effect of selenium (Se) supplementation on semen quality of Saanen goats following induced stress. Forty Saanen bucks were divided into two main groups: selenium supplementation and control. The groups were further subdivided into two groups each comprising of induced stress (injected with adrenocorticotropic hor...

Objective: To evaluate the effect of cooling rates, selenium supplementation, and three semen extenders on cooled and frozen-thawed Saanen buck sperm. Methods: Twenty Saanen bucks were divided into two groups: the selenium supplemented group and the control group. Ejaculates were collected once weekly by artificial vagina. The first experiment exam...

The present study evaluated the effect of β-carotene supplementation and oestrous synchronization protocol on ovarian activity and fertility of Saanen does during the breeding season. The supplemented group received 100 mg β-carotene during the breeding and all does were synchronised with Controlled Internal Drug Release dispenser (CIDR) and inject...

The aim of this study was to characterise and compare phenotypic characteristics of South African unimproved indigenous and Tankwa goats. Phenotypic characteristics of 44 South African unimproved indigenous and 41 Tankwa goats were assessed. The qualitative characteristics were assessed through visual appraisal. Quantitative characteristics such as...

The aim of this study is to determine the effect of β-carotene supplementation during breeding, pregnancy, parturition and lactation on the production and reproduction traits of Merino ewes.

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 el...

Background: Alterations in maternal environment can sometimes affect embryonic development in a sexually-dimorphic manner. The objective was to determine whether preimplantation bovine embryos respond to three maternally-derived cell signaling molecules in a sex-dependent manner. Results: Actions of three embryokines known to increase competence...

The effects of high thermal stress on serum protein metabolites, milk production of transition dairy cows in semi-arid areas in South Africa were evaluated. Forty, ± 8 months pregnant, Jersey heifers (± 26 months) in zero grazing management were selected during summer from two semi-arid communal areas. Summer thermal-humidity index (THI) of the are...

Although WNT signaling regulates several developmental processes, its specific role during preimplantation development remains unclear. The present aim was to evaluate the consequences of activation and inhibition of β-catenin (CTNNB1) dependent and -independent WNT signaling in the bovine preimplantation embryo. Activation of CTNNB1 mediated WNT s...

The purpose of the study was to examine attainment of puberty in South African unimproved indigenous bucks (unimproved indigenous bucks). A total of 24 unimproved indigenous bucks aged between 118 to 123 days (4 months) with a mean body weight of 8.1 ± 0.3 kg were observed for puberty attainment. Their sexual behaviour activities, body weight and s...

Zulu sheep is a Nguni breed indigenous to the KwaZulu-Natal (KZN) province of South Africa, and is reported to be under threat of extinction. Knowledge of factors that may cause the declining numbers is required for the planning of conservation programmes. We designed a study to evaluate the effect of ram age, season and geographic location on the...

The objective of this study was to determine the effect of orally supplemented sodium selenite on body weight, testes measures, semen attributes and hormone concentrations of Saanen bucks. Twenty mature healthy Saanen bucks were divided into two equal groups (10 bucks). The treatment bucks received sodium selenite at 10-day intervals for ninety day...

This study evaluated the effect of breed and follicular status of Boer and indigenous goats on response to superovulation and embryo yield. The oestrous cycles were synchronized with progestagen for nine days and superovulated with porcine follicle-stimulating hormone. Does were cervically inseminated and embryos were surgically flushed on day six...

Successful in vitro development of embryos is dependent upon maintenance of cellular function in the embryonic microenvironment. Exposure of pre-implantation embryos to a variety of cellular stresses can induce apoptosis in all or a fraction of blastomeres. Among the conditions that can induce apoptosis in cattle embryo production in vitro are heat...

Egg yolk is a common constituent of semen extender and protects sperm against cold shock. Besides its protective characteristic, chicken egg yolk is mostly included in extenders for semen preservation due to its abundant availability. The aim of the study was to compare egg yolk sources from different indigenous chicken egg yolk sources and storage...

The aim of this study was to determine the sperm fertility rate by embryo production in vivo and in vitro in South African bulls and further compare the embryo quality developed from different oocyte recovery methods. A total of 15 frozen semen straws (5 Bonsmara; 5 Nguni; 5 Boran) were thawed and evaluated for sperm motility characteristics using...

The embryo transfer techniques used in small ruminants worldwide are based in surgical procedures. These actions are performed under general anesthesia which needs a combination of animal fasting and drugs for secure animal handling and surgery manipulations. Therefore, it involves risks to animal health and life. The major limiting sequels are adh...

Cow live weight is of economic importance in dairy production; however, it is not included in the selection objective for South African dairy cattle. Variance components estimates are a prerequisite to incorporating a trait in the breeding objective. Variance components were estimated for live weight of lactating Holstein cows on two South African...

Introduction A primary goal in dairy cattle breeding is to improve the profitability of milk production. In order to achieve such improvement, all economically important traits should be included in the selection objective. Genetic and environmental parameters influencing live weight are essential in the selection objective and may help to increase...

This study was conducted to evaluate the use of one shot follicle stimulating hormone (FSH) plus equine chorionic gonadotrophin (eCG) (simplified) superovulation protocol in mature Boer goat does. Eighteen does used were allocated into two groups, during the natural breeding season (autumn). The two group were Group 1: the control (n = 9); multiple...

This study evaluated the effect of breed and follicular status on quantity and quality of embryos recovered following superovulation in South African goats. Mature, nonlactating Boer (n=10) and unimproved indigenous (n=10) goats were used in this trial. Oestrous cycles of does were synchronised with controlled internal drug release (CIDR(®); Pfizer...

The 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 dr...

The aim of this study was to cryopreserve and evaluate frozen-thawed semen parameters. Electroejaculator was used to collect semen from six bucks. Semen samples were divided into two parts. In one part, seminal plasma was removed and was not in the other one. Both semen sample parts were extended with egg-yolk Tris extender. Semen was thereafter cr...

Ovine embryonic development was evaluated 8 days following in vitro fertilization, after using fresh or frozen-thawed Merino and indigenous (Pedi and Zulu) sheep semen. Semen used was collected twice weekly over a 3-month period with the aid of an electro-ejaculator. Following collection, semen samples were evaluated and semen with acceptable sperm...

No studies have investigated the IVF rate of South African indigenous Kolbroek sperm cells following cryopreservation. The objective of this study was to test if frozen-thawed Kolbroek pig sperm cells could penetrate pig oocytes matured in vitro. Pig ovaries were collected from a local abattoir and cumulus-oocytes complexes were obtained by aspirat...

This study evaluated the effect of breed on the survivability and motility rate of cryopreserved cock semen. Semen from three cock breeds; White Leghorn (WL), Ovambo (OV) and Potchefstroom Koekoek (PK) was collected by means of the abdominal massage technique. Following semen collection, sperm were analyzed for motility and survivability with the u...

The study evaluated the effect of different cryoprotectants on post-thaw survival and motility of Kolbroek sperm. Semen from Kolbroek boars was collected with the gloved hand technique. Ejaculates were diluted with Beltsville thawing solution (BTS) at a ratio of 1 : 1 prior to freezing. Semen was diluted with egg yolk tris; thereafter, one of the t...

Twenty-four Boer goat does were used to compare three superovulation protocols, with 8 does allocated per treatment during the natural breeding season. In Group 1 (Day 0 protocol), the oestrous cycles of does were synchronised for 7 days with CIDR's and injected PGF2α at CIDR insertion. Does were then superovulated with pFSH in 7 dosages at 12 h in...

Cryopreservation of embryos is an important technique in the whole MOET program, which could help improve the transportation of genetic material across South Africa and globally. This trial evaluated the survival rate of goat embryos following transfer with cryopreserved Boer goat embryos. Twenty-seven multiparous Boer goat recipients were synchron...

This study was conducted to evaluate the effect of the age and parity of the embryo donor on the superovulatory response and embryo recovery rate in Boer goat does. The oestrous cycles of seven maiden does (young, 1 - 2 years) and nine multiparous does (adult, 3 - 4 years) were synchronised using controlled internal drug release dispensers (CIDR's)...

The aim of this trial was to evaluate the effect of embryo cryopreservation techniques on the survivability of embryos and fertility following transfer to Boer goat does. The oestrous cycles of 27 mature recipients Boer goat does were synchronised using controlled internal drug release dispensers (CIDR's) for 16 days. At CIDR removal, does were inj...

Seventeen Boer goat does were used in this study to compare the effect of an intramuscular or subcutaneous route of administrating a superovulation treatment during the natural breeding season (autumn). The oestrous cycles of all does were synchronised for 17 days using CIDR dispensers and superovulated with pFSH administered in 7 dosages, at 12 h...

________________________________________________________________________________ Abstract This study evaluated the effect of repeated superovulation and embryo recovery in 15 Boer goat does. Does were synchronised for oestrus using CIDR's for 17 days and superovulated with pFSH during the natural breeding season (autumn). Cervical inseminations wit...

The study evaluated the effect of different cryoprotectants on post-thaw survival and motility of Kolbroek sperm. Semen from Kolbroek boars was collected with the gloved hand technique. Ejaculates were diluted with Beltsville thawing solution (BTS) at a ratio of 1 : 1 prior to freezing. Semen was diluted with egg yolk tris; thereafter, one of the t...

The study evaluated the effect of different cryoprotectants on post-thaw survival and motility of Kolbroek sperm. Semen from Kolbroek boars was collected with the gloved hand technique. Ejaculates were diluted with Beltsville thawing solution (BTS) at a ratio of 1 : 1 prior to freezing. Semen was diluted with egg yolk tris; thereafter, one of the t...

This study evaluated the effect of breed on the survivability and motility rate of cryopreserved cock semen. Semen from three cock breeds; White Leghorn (WL), Ovambo (OV) and Potchefstroom Koekoek (PK) was collected by means of the abdominal massage technique. Following semen collection, sperm were analyzed for motility and survivability with the u...

This study was conducted to evaluate the effect of season on the superovulatory ovarian response and embryo recovery rate in Boer goat does. Twenty mature does (mean body weight of 55kg) were synchronised for oestrus with the aid of CIDR devices for a period of 17 days and superovulated with pFSH (Folltropin®-Vetrepharm) during the natural breeding...

The aim of this study was to evaluate the ovarian response and embryo recovery rates in Boer goat does superovulated with pFSH following a pre-treatment with a GnRH agonist (GnRHa) outside the natural breeding season. Oestrus was synchronised in 22 does with CIDR's for 17 days, and these were superovulated with a total dose of 200 mg pFSH/doe admin...

A trial was conducted to evaluate the effect of pre-treatment with a GnRH agonist (GnRHa) on the superovulatory response in Boer goats during the natural breeding season. Twenty-one does were synchronised with CIDR's for 17 days and superovulated with a total dose of 200 mg FSH/doe, administered i.m. in seven dosages, at 12 h intervals, starting 48...

The reproductive performance following oestrous synchronisation and artificial insemination (AI) was evaluated during the natural breeding season (autumn) in 90 indigenous (Boer and Nguni) South African goats. All does were synchronised for 16 days with medroxyprogesterone acetate (MAP) followed by an IM injection of 300 IU PMSG at progestagen with...