M. Tech. Agriculture / Herbs are a rich source of active phytochemicals (flavonoids, phenols, antioxidants, ascorbic acid, carotenoids, mineral salts and terpenoids. They are an ancient source of flavouring, aromatic compounds and medicine. Herbs have always constituted an important component of the human diet, adding variation and flavour to staple foods, as well as being used for food preservation. They are mostly processed because of the perishable nature of its leaves. The quality of herbs therefore can be improved by the manipulation of light quality during production and also by sheltering them from environmental hazards such as excessive solar radiation, wind and flying pests. In this study the effect of photo-selective netting technology (ChromatiNet™) (red, pearl and yellow) with 40% shading and commercial black net with 25% shading used as a control were investigated on herbs. Three herbs (coriander, marjoram and oregano) were planted. The aim of the present study was to evaluate the responses of the three photo-selective nets (red, pearl and yellow) and the black net (control) on quality parameters and bioactive compounds in herbs (in this study, coriander, marjoram and oregano).

M. Tech. Agriculture / Mungbean (Vigna radiata L. Wilczek) is becoming a food security crop in Africa, especially in South Africa where there is a growing Asian population. To promote its production by farmers, 15 elite mungbean varieties were evaluated for plant growth, symbiotic N (nitrogen) nutrition and grain yield at Nelspruit and Kliplaatdrift in Mpumalanga Province, South Africa. Genotypes VC6486-10-S1 and VC6493-44-1 at Nelspruit, and VC6510-151-1, VC1973A and VC3960-88 at Kliplaatdrift showed better growth and fixed significantly more symbiotic N than the other genotypes. They also seemed to obtain more N from soil. At both Nelspruit and Kliplaatdrift, two genotypes (namely, VC6510-151-1 and VC6493-44-1) exhibited much greater δ¹³C (carbon) values, and hence higher water-use efficiency. A comparison of P (phosphorus) nutrition between Nelspruit (received no P) and Kliplaatdrift (received 20 kg P.ha-1) revealed mineral P suppression of acid phosphatase activity in the rhizosphere of all fifteen mungbean genotypes at the latter site. The findings further showed that there is a direct functional relationship between water-use efficiency and N2 fixation, and between water-use efficiency and P nutrition.

Electrophoresis (horizontal starch gel and PAGE) was used to study the genetic diversity and uniqueness of an endemic southern African domestic dog (Africanis) breed. The results were compared to those of three other populations/breeds: blood samples obtained from the Society for the Prevention of Cruelty to Animals (SPCA); indigenous Middle Eastern dog breed (the Saluqis) and hybrid (mongrel) dogs from the Jericho-area, near Brits (South Africa). Gene and phenotypic allele frequency and genetic differentiation were analysed at 21 protein coding loci. Nine polymorphic loci were identified (AK-1, -2, CK, PER, Hb, PA-1 to -3 and P-Tf). The average heterozygosity ranged from 0.106 to 0.159; the percentage of polymorphic loci were the least in the Saluqi (23.81%) and ranged to 33.33% in the Jericho breed; and the mean number of alleles per locus varied from 1.33 (Saluqi) to 1.43 (Jericho). Significant deviations (P<0.05) of allele frequencies from expected Hardy-Weinberg proportions occurred in loci AK-1, -2, Hb and P-Tf. These loci can serve as markers to define groups (i.e. only Africanis showed the presence of private alleles, CK*B and PA-2*C). The genetic distance values (D78) were between 0.001 and 0.026, with the smallest distance between Africanis and Saluqi, and the largest distance between Jericho and Africanis. This former, small D-value indicates a close genetic relationship between Africanis and Saluqis, supporting archaeological evidence that the endemic Africanis breed has indeed been introduced from the Middle East thousands of years ago, and not through western influences. These results are discussed with specific reference to genetic variation and differentiation that makes the endemic southern African domestic dog breed unique. / Prof. F.H. Van der Bank

M. Tech. Agriculture / Tomatoes (Solanum lycopersicum) and sweet or bell peppers (Capsicum annuum L.) belong to the Solanaceae family. They constitute an excellent source of phenolic (flavonoids), vitamin C (ascorbic acid) and carotenoids (especially lycopene, b- carotene, a precursor of vitamin A), known as antioxidants. The aim of this study was to investigate the influence of photo-selective nets (ChromatiNet™) (red, pearl and yellow) with 40% shading on postharvest fruit quality parameters (Soluble solids content, Titratable acidity, fruit mass and firmness), bioactive compounds (ascorbic acid, total phenols, flavonoid, lycopene, b-carotene contents), antioxidant scavenging activity, odour active aroma compounds and the sensory quality of three indeterminate sweet pepper cultivars HTSP-5 (green), HTSP-3 (red) and Celaya (yellow) and three tomato cultivars (AlfaV, Irit, and SCX 248). A commercial black net (control) with 25% shading was included for comparison.

Adequate and appropriate nutrition is essential for the production of high quality commercially farmed animal species. Although South Africa has had a well-established ostrich industry for over a century, little information on ostrich nutrition, in particular the specific nutritional requirements at different stages of production, is available. The industry has consequently relied heavily on data derived from poultry and pigs, but this has often proved to be unsatisfactory for ostriches and has resulted in serious nutritional-related problems. Recent studies on the metabolisable energy of specific components of diet formulations and balanced diets have indicated that ostriches have enhanced digestibility compared with poultry and pigs. At the same time, in the present economic climate, it is necessary to find cost-effective diets for breeding birds without compromising egg and chick production. This study primarily assessed the effect of different dietary protein and energy levels on production parameters and body condition of breeding female and male ostriches. The energy content of the diet appears to be the main constraint to egg production and breeders on low energy diets laid fewer eggs and lost more body condition compared with breeders fed higher energy diets. A diet with 8.5 MJ/kg DM and 10% protein with well balanced amino acids appears to be sufficient for female breeders without compromising production and a diet with 7.5 MJ/kg DM and 10% protein appears suitable for breeding male ostriches. Different dietary energy and protein levels similarly had little or no effect on egg quality and composition. This study also assessed the carry-over effect of the nutritional regime in one year on the production in the following breeding season. Females fed diets as low as 7.5 MJ/kg ME in the previous breeding season produced significantly fewer eggs in the next breeding season, which resulted in lower chick production. Energy had no effect on the percentage infertile eggs or on the initial egg weight. Different levels of dietary protein had no effect on egg production, egg weight, fertility, hatchability and initial chick weight.

Thesis (M. Tech.) -- Central University of Technology, Free State, 2007 / Four different South African indigenous (Naked Neck (NN), Ovambo (OVB), Venda (VD) and Potchefstroom Koekoek (PK) chicken breeds were used in this study. From each of the four breeds of chicken, 40 hens and 8 cocks were selected randomly. Two groups each of sixteen cocks were subsequently formed: high performing (HP) and low performing (LP) groups to determine the relationships between cock semen viability and the fertility of artificially inseminated South African indigenous layer breeds. Semen was collected following five minutes of sexual massage (5SM) and evaluated for semen volume (ml), sperm motility (%), live sperm (%) and total sperm (x109/ml). Semen from each cock was then used to inseminate five hens per breed, in each treatment. Each hen was inseminated twice a week throughout the duration of the trial. During the experimental period, each hen was inseminated with 0.05 ml diluted semen. The artificially inseminated hens were examined for average egg weight (g), fertility (%), hatchability of set eggs (%), live chicks (%), normal chicks (%) and chick weight (g). A total of 1600 eggs, i.e. 400 eggs from each breed were collected in three batches following artificial insemination from individually caged hens and were hatched to compare hatching parameters among breeds. The hatchability traits of hens of the four breeds (NN, OVB, PK and VD) were compared. Hatching egg weight had significant (P < 0.05) difference among the four breeds. The results of this study indicate that semen viability exemplified by ejaculate volume, sperm motility; live sperm and total sperm per ejaculate were significantly (P < 0.01) superior in the HP cocks compared to the LP cocks. Hens inseminated with semen from the HP cocks in each experimental group resulted in higher egg weight (g), fertility (%), hatchability of set eggs (%), live chicks (%), normal chicks (%) and chick weight (g). Significant positive relationships existed between semen volume and sperm motility (P < 0.05), semen volume and live sperm cells (P < 0.01), semen volume and total sperm (P < 0.01) in NN, OVB and VD, with negative correlations in PK. Some positive correlations were found between sperm motility and live spermatozoa (P < 0.01), sperm motility and total sperm (P < 0.01), live sperm and total sperm (P< 0.01) in NN, OVB, PK and VND. Fertility was the highest in the HP group. Fertility was also the highest in PK, intermediate and similar in OVB and NN and lowest in VD (P<0.05). Breed had a significant effect on hatchability of fertile eggs (P<0.05). Hatchability of total eggs set was highest in PK and NN, intermediate in OVB and lowest in VD (P<0.05). Breed had a significant effect on live, normal chicks and chick weight (P<0.05). Live chick was the highest in NN, whereas at day-old, normal chick and chick weight at hatching were the highest (23.50 ± 0.11) (P<0.05) in PK (98.14 ± 0.67 vs. 37.90 ± 0.28 g), intermediate and similar in NN (87.90 ± 0.63 vs. 23.50 ± 0.11) and OVB (87.75 ± 0.45 vs. 32.81 ± 0.49 g) and the lowest but with an acceptable value in VD (76.85 ± 0.46 vs. 26.90 ± 0.36 g). There were some correlations among different hatchability traits depending on breed. The correlations were more profound among PK. It was clear that chick weight as percent of egg weight was not just a function of egg weight, and that genotype also played an important role favouring the heavier breeds. The results obtained in this study on the relationships between cock semen viability and the fertility of artificially inseminated South African indigenous layer breeds elucidate that the use of high performing (HP) cocks following five minutes of sexual massage, prior to semen collection and artificial insemination of layers is a practical method for optimising sperm viability and subsequent fertility of hens. The results of this study suggest that the Potchefstroom Koekoek (PK) cocks and hens are superior to the Naked Necks (NN), Ovambo (OVB) and Venda (VD). The Ovambo and Naked Neck cocks ranked second in donating quality semen as well as in improving the fertility and hatchability traits of the indigenous chicken breeds. Thus selection of high performing cocks through five minutes sexual massage prior to semen collection and use is recommended for poultry AI breeding programmes.

Thesis (M. Dev.) -- University of Limpopo, 2017 / There is a gap in the literature about the role and relevance of Indigenous Knowledge and beef cattle welfare in many parts of the Limpopo province. This gap is relevant because many marginalised cattle owners use indigenous knowledge in their day to day management of beef cattle. The aim of the study is to investigate the use of IK methods on beef cattle husbandry in Tshebela village in the Capricorn district of the Limpopo province as a contribution to filling the void identified above. The objectives of the study were as follows:  -To investigate the IK methods used in beef cattle husbandry in the area of the study;  -To assess if beef farmers use IK to identify medicinal plants to cure beef cattle;  -To investigate farmers‘ perceptions and attitudes on the use of IKS on beef cattle husbandry in the area of study. A qualitative methodology that was used was primarily phenomenological in design. A purposive sampling technique was used and twenty seven (27) traditional beef farmers, two (2) local herbalists were recruited as participants. Data was collected through focus group discussions, key informant interviews, and observations. An interpretative phenomenological-based analysis was used to surface the role and relevance of indigenous knowledge in beef cattle husbandry. The findings suggest that indigenous knowledge is used by cattle owners alongside modern knowledge and that communal farming posed some challenges to the farmers.

M. Tech. Agriculture / South African unimproved indigenous goats are disease tolerant, able to survive on harsh conditions such as extreme temperatures and poor vegetation. It is therefore, important to include this breed in breeding objectives during this time of climate change and when animals are resistant to antibiotics. However, these goats are under threat of extinction and very little information on their reproductive status is recognized. In order to improve or maintain South African unimproved indigenous goats, basic science concerning male fertility, semen quality and production should be investigated to conserve genetic materials for future breeding. Conflicting results have been reported concerning the effect of semen collection techniques on buck sperm quality. Longevity of sperm following semen collection is a major limitation to use fresh semen for artificial insemination in rural communities where majority of South African unimproved indigenous bucks are kept. Extenders such as Tris, egg yolk and cow skimmed milk have been used to prolong the survivability of buck sperm in other countries, but contradictory results have been reported concerning which extender is more suitable for buck semen. Egg yolk based extenders have been used mostly in buck semen compared to Tris or cow skimmed milk based extenders. The purpose of the study was to compare semen collection techniques on South African unimproved indigenous goat semen, and the utilization of indigenous chicken egg yolk for preserving South African indigenous buck semen.

Thesis (M.A. (Agricultural Management)) -- University of Limpopo, 2013 / A study was conducted to determine environmental and socio-economic factors affecting pig productivity in communal areas. A questionnaire was administered to collect data on production environment and socio-economic variables underlying productivity in Sekhukhune District. Production environment included explanatory sex of the piglet, season of birth, feed type, housing type, municipality, herd size, health management and disease prevalence, while socio-economic variables included household size and gender of head of household, age, level of education and employment status. A total of 112 farmers were interviewed from 25 villages. Data on productivity were collected using production record sheets. Performance parameters in the production sheets included litter size, litter weight, individual birth weight, live weight and mortality. Monitoring was done from birth date to subsequent farrowing date at the farmers’ backyard. One farrowing sow per producer was used and a total of 605 piglets were monitored in the municipalities. A total of 1468 indigenous pigs were kept for breeding with 104 castrated males occupying less space in the production system within the district. Feeding was characterized by kitchen wastes or garbage at total of 78 farmers, 22 feeding garbage and grains, and only 12 farmers feeding concentrate. There was measles prevalence in the production system with a total of 41 farmers treating the suspected pigs; the larger number (71) however, did not treat pigs. Health did not affect (P>0.05) litter size and birth weight. Birth weight was affected (P>0.05) by disease prevalence, herd size, household head sex, age and education, and family size. Mean litter size was 4.38 piglets at birth, mean litter weights of 5.78 kg, mean birth weight of 1.32, and mean mortality at 2.31 piglets. Season, feed, municipality, diseases, herd size, the age, education and employment of household head affected pre-weaning mortality (P<0.05). v There is statistical evidence (P<0.05) that there were associations between litter size, litter weight, birth weight and mortality and the feed, municipality, diseases, herd size, the age, education and employment of household head respectively. There were deficiencies in the entire production system with regards to pig management practices, feeding practices, housing of pigs, breeding systems, herd composition and size and the general practices in the keeping of the pig herds by majority of pig producers. These deficiencies call for introduction of sound pig management plans in communal areas which should include keeping pigs indoor to account for the healthy herd, proper feeding and sound breeding plans.

Thesis (Ph.D. ( Animal breeding)) --University of Limpopo, 2012 / Refer to document / the Agriculture Research Council