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The South African broiler sector is the largest agricultural sub-sector. It contributed R37.2 billion or 16.5 % to the total agricultural sector in the 2014/15 season (DAFF, 2016:76). The industry produced ± 962 million broilers in 2014 and ± 1 003 million in 2015 (SAPA, 2016b). The Department of Agricultural Forestry and Fisheries (2015:69) reported per capita consumption of 16,11 kg in 1993/94 and 38,5 kg in 2013/14 season, which constitutes a growth of 140 % over the past 20 years. The Bureau for Food and Agricultural Policy (BFAP) estimated that consumption would increase by a further 38 % from 2014 to 2024 (BFAP, 2015:74). Chicken meat remains an affordable protein, as against pork and beef (Lovell, 2014a:12). The industry employs ± 10% of the total agricultural workforce (IDC, 2016:66). From a supply and demand perspective, South Africa consumed 2 127 389 tonnes of broiler meat in 2015 (South African Poultry Association (SAPA), 2016a: 1). The local production by commercial and subsistence farmers, together with imports are as follows. Commercial farmers produced 1 720 155 tonnes in 2015. Importers, retailers, and wholesalers imported 457 374 tonnes. Subsistence producers produced 69 334 tonnes. Live sales from depleted stock comprised 71 885 tonnes, and exports formed 65 815 tonnes (SAPA, 2016a: 5). The trade in broiler meat of certain cuts and mechanically deboned meat (MDM) is a vibrant and active market. The value of imports increased by 139 % from R1,5 billion in 2010 to R3,6 billion in 2015 (SARS, 2016). World broiler meat prices decreased between 30 % and 40 % from 2014 to 2016 (Unnerbary, 2016). The northern hemisphere prefers ‘white’ chicken meat (mostly breast meat). Because of this preference, research and development in the USA and EU poultry industries have resulted in larger chickens produced. This phenomenon results in surplus production in the specific markets of brown meat (drumsticks and thighs), which needs to be sold in other global markets.

English: According to Liversage (2003: 1) maize was marketed through the one channel marketing system between 1944 and 1994. According to this system the Maize Board and its agents (the former agriculture co-operatives) were responsible for the buying and storing of maize in South Africa (Maize Board 1987: 134-147). After the closing of the Maize Board, a free market system was implemented and currently any person or organization can store maize (Murray, 2011: personal communication) in South Africa. Due to the above mentioned changes, 1.85 million tons of storage capacity was erected on farms in South Africa since 1996 (SIQ, 2011). Apart from storing maize at the silos of commercial storage companies, maize can also be stored on the farm by using zinc silos, silo bags and grain dams according to Genis (2012). If storage takes place on the farm it will need the erection of storage structures. Dhyuvetter (2007: 4-6) showed that additional capital is needed to erect new storage structures on the farm. According to Steitz & Ehmke (2005) any capital expenditure, influences the farm over a long period and need careful planning (Boehlje & Ehmke (2005: 1). According to Louw (1996: 20) models for complete farm planning can be used to evaluate the effect of capital spending on the farm. According to Koch (1992: 20) these models take the soil, farm operations, market plans and capital resources into account when different options is evaluated by developing varies scenarios. There is currently no farm planing model available in South Africa witch can be used to evaluate the effect of different storage methods on the use of capital resources of the farm. In this study ‘n holistic farm planning model is developed to be use in evaluating the effect of different storage methods on the use of capital on a maize farm. The effect of the use of commercial silos and the use of zinc silos, silo bags, plastic dams and zinc dams is evaluated in the study. The effect of certain variables l, Afrikaans: Volgens Liversage (2003: 1) is mielies tussen 1944 en 1996 in Suid-Afrika volgens die eenkanaalbemarkingstelsel bemark. Ingevolge die stelsel kon slegs die Mielieraad en sy agente (die eertydse landbou koöperasies) mielies in Suid-Afrika aankoop en opberg (Mielieraad 1987: 134-147). Na die sluiting van die Mielieraad is ’n vryemarkstelsel geïmplementeer en kan enige persoon of instansie mielies opberg (Murray, 2011: persoonlike mededeling). Weens die veranderinge in die bemarkingsomgewing as gevolg van die aspekte wat hierbo bespreek is, is 1.85m ton opbergingskapasiteit volgens SIQ (2011) sedert 1996 op die plase in Suid-Afrika geskep. Volgens Genis (2012) word sinkbuise, silosakke, en graandamme tans gebruik om mielies op die plaas op te berg, terwyl mielies ook by die silo’s van kommersiële opbergers opgeberg kan word. Die opberging van mielies op die plaas gaan gepaard met die oprigting van strukture op die plaas. Dhyuvetter (2007: 4-6) het aangetoon dat bykomende kapitaal nodig is om opbergingstrukture op die plaas op te rig. Enige kapitale spandering, beïnvloed volgens Steitz & Ellision (2005), die boerdery oor ’n lang periode en moet volgens Boehlje & Ehmke (2005: 1) deeglik beplan word. Volgens Louw (1996: 20) kan geheelplaasbeplanningsmodelle gebruik word om die effek van kapitale spandering te evalueer, aangesien ’n geheelbeeld van die boerdery verkry word as ’n geheelplaasbeplanningsmodel gebruik word. Volgens Koch (1992: 20) neem geheelplaasbeplanningsmodelle aspekte soos die boerdery se grond, bewerkingspraktyke, bemarkingsplan en kapitaal in ag en word al die aspekte geïntegreer ten einde verskillende scenario’s te evalueer. Tans bestaan daar nie ’n geheelplaasbeplanningsmodel in Suid-Afrika wat gebruik kan word om die effek van die verskillende opbergingsmetodes op die aanwending van ’n boerdery se kapitaal te evalueer nie. In die studie word ’n geheelplaas-beplanningsmodel ontwikkel wat gebruik word om die effek van die verskillende opberg

Although the maintenance of precise balance between coagulation and fibrinolysis is of utmost importance for normal haemostasis, until recently these two systems were considered as completely separate mechanisms involved in the process of formation and dissolution of blood clot. Thrombin activatable fibrinolysis inhibitor (TAFI) is a recently described attenuator of the fibrinolytic rate and is considered to be the molecular link between coagulation and fibrinolysis. TAFI circulates in plasma as an inactive precursor and its conversion in active enzyme (TAFIa) occurs by the action of thrombin or plasmin, but most efficiently by thrombin in the presence of its cofactor thrombomodulin. Once generated, TAFI down-regulates fibrinolysis by removing C-terminal lysine residues from partially degraded fibrin; thereby preventing the upregulation of plasminogen binding and activation. Because TAFI is activated by thrombin on one side, and acts as the attenuator of fibrinolysis on another side, it enables fine synchronization between these two systems. The antifibrinolytic function of TAFI mostly depends on TAFI concentration, the rate of its activation and the half-life of TAFIa in plasma. Changes in thrombin generation can have a profound effect on the rate of TAFI activation, and consequently on the rate of fibrinolysis. Therefore, it has been hypothesized that increased thrombin generation seen in thrombophilia patients may enhance TAFI activation, leading to a hypofibrinolytic state, which may further contribute to the thrombotic tendency. However, the results of several studies, in which relation between TAFI level and the occurrence of thromboembolic complications in carriers of hereditary thrombophilia have been investigated, were not consistent.

Introduction: It is considered that high plasma levels of procarboxypeptidase U (proCPU or TAFI) can promote the development of thrombosis, but data comparing proCPU levels in thrombophilia carriers and healthy subjects are rather scarce. Moreover, the results of previous studies on the risk of thrombosis related to high proCPU concentration in this population were not consistent. Although the 325 polymorphism, of proCPU has a significant effect on the CPU half-life, it's influence on the risk of thrombosis or spontaneous pregnancy loss in carriers of hereditary thrombophilia is not clear. Materials and Methods: The study population consisted of 144 thrombophilic patients (94 heterozygous and 10 homozygous carriers of FV Leiden, 26 heterozygous carriers of the prothrombin G20210A variation and 14 double carriers of FV Leiden and FII variation) and 69 healthy controls. Results: The results show that patients with inherited thrombophilia have a tendency toward lower mean proCPU plasma levels compared to healthy controls, however, this difference was only significant in carriers of FII G20210A (p = 0.014). A higher frequency of the most stable Ile325Ile proCPU was seen among carriers of I'll G20210A mutation compared to the control group (19% vs 7%; p = 0.186). In the second part of the study proCPU as a risk factor for thrombosis was evaluated. In heterozygous carriers of FV Leiden or FII G20210A high levels of proCPU conferred to an almost 4-fold increased risk for spontaneous onset thrombosis. The more stable Ile325Ile proCPU seems to impose a higher risk for clinical manifestation of the thrombophilic condition. Finally, a significant positive correlation between F1 + 2 and proCPU concentration was seen. Conclusion: The increased risk of thrombosis in thrombophilia patients is not only ascribable to an increased thrombin generation, but also high levels of proCPU and the presence of the 325Ile genotype tip the balance towards thrombotic tendency even further.