La spécialisation des systèmes agricoles et des territoires montre ses limites, principalement d’un point de vue environnemental mais aussi économique si les prix augmentent. La diversification et l’intégration de culture et d’élevage au sein des exploitations apparaît être une solution de production plus durable, mais leur fonctionnement n’est pas totalement appréhendé. Nous émettons les hypothèses qu’il existe des conditions d’intégration sous lesquelles les systèmes de polyculture-élevage (PCE) sont effectivement plus durables que les systèmes spécialisés et que les méthodes de caractérisation et d’évaluation des systèmes de polyculture-élevage ne permettent pas d’identifier ces conditions. Dans l’objectif de vérifier ces hypothèses, nous avons développé le modèle Sheep’n’Crop pour simuler des systèmes de polyculture-élevage ovin allaitant contrastés auxquels deux types d’analyses ont été effectuées : (i) analyses d’indicateurs économiques, de productivité et environnementaux (GES, MJ, bilan N) à l’échelle de l’exploitation agricole et des ateliers de production en vue d’évaluer la durabilité des systèmes, et (ii) analyse d’efficience énergétique à partir de la méthode de frontière de production DEA pour caractériser la complémentarité des ateliers de culture et d’élevage. Ces analyses ont été menées sur trois stratégies de production à possibilités d’interactions décroissantes – systèmes intégrés, non-intégrés, diversifiés fictifs – au sein desquels l’organisation culture-élevage (% culture) et la saisonnalité de la production ovine (printemps ou automne) varient. L’évaluation de la durabilité montre que les interactions culture-élevage et une mise-bas de printemps permettent d’améliorer tous les indicateurs de durabilité, mais un pourcentage de culture élevé réduit les performances pour la consommation d’énergie non-renouvelable et le bilan azoté. La caractérisation de l’intégration des systèmes PCE par leur gain d’efficience énergétique – la complémentarité - montre que les systèmes intégrés et non-intégrés simulés sont plus efficients que les systèmes diversifiés fictifs de +6.4% et +0.4%. Le lien entre l’indicateur de complémentarité et la durabilité des systèmes est néanmoins difficile à établir étant donné l’existence de trade-off. Nous recommandons de compléter ces résultats en améliorant la considération des contextes pédoclimatiques et socio-économique, de l’efficience d’échelle de production, du niveau d’intensification de l’atelier animal et des effets agronomiques et techniques des interactions culture-élevage. / Specialization of farming systems and territories are not environmental-friendly, moreover those systems are threatened by the expected higher prices of inputs of production. Diversification and integration of crop and livestock at the farming system scale appears to be a valuable way to enhance farming system sustainability. We posit that they must be conditions of integration that permit mixed crop-livestock systems to be more sustainable than specialized systems and that existing methods of mixed crop-livestock systems characterization do not permit identifying those conditions. To test those hypothesis, we designed a whole-farm model – Sheep’n’Crop – that permits simulating contrasted mixed crop-livestock systems and evaluating (i) their sustainability through economic, productive and environmental (MJ, GHG, N balance) indicators and (ii) their energetic efficiency through a DEA production frontier analysis in order to characterize the complementarity that exists between crop and livestock subsystems. Those analyses were run on three contrasted farming system strategies, distinguished by a decreasing possibility of interactions between crop and livestock subsystems: integrated systems, non-integrated systems and virtual diversified systems. Those systems are also characterized by various crop-livestock organizations (% of crops) and lambing’s periods (spring or autumn). The analysis of sustainability indicates that crop-livestock interactions and spring seasonality permit enhancing each performance of sustainability. However, a high percentage of crops makes decrease the MJ consumption and N balance performances. The characterization of mixed crop-livestock systems through their energetic efficiency gains – the complementarity – show that integrated and non-integrated systems are respectively more efficient than virtual diversified systems by +6.4% and +0.4%. Comparing the complementarity index and indicators of sustainability of farming systems, we highlighted the existence of trade-off. Before analyzing and identifying the best trade-off compromise, we recommend completing our results by testing various pedoclimatic and socio-economic context, the effect of scale efficiencies, the effect of livestock intensification and increasing agronomic and technical effects of crop-livestock interactions.

Thesis (Ph.D. (Animal Nutrition)) -- University of Limpopo, 2016 / Refer to document

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MSCAGR (Animal Science) / Department of Animal Science / The objectives of the study were to evaluate the effect of two extenders (Triladyl® and Bioxcell®) and the removal of seminal plasma on goat buck semen. Six ejaculates were collected from six indigenous bucks by means of electro-ejaculator method, and semen was pooled, and replicated 10 times. Raw semen were randomly allocated into six groups as follows: (i) Raw non-washed, (ii) Raw washed, (iii) Triladyl®-washed, (iv) Triladyl®-non-washed, (v) Bioxcell®-washed and (vi) Bioxcell®-non-washed. All six groups were analysed for spermatozoa motility rates using computer-aided sperm analysis (CASA). The spermatozoa viability for all groups were assessed using Eosin-Nigrosin, acrosome integrity using Spermac, chromatin structure using Acridine Orange, and mitochondria using JC-1 staining solutions. Both the Triladyl® and Bioxcell® washed semen groups were diluted (1:4) with Phosphate Buffered Saline (PBS) then centrifuged at 1500 x g for ten min and seminal plasma was aspirated using 1 mL sterile plastic pipette. Semen samples were diluted (1:4) as follows: Triladyl® (washed and non-washed) or Bioxcell® (washed and non-washed) and then equilibrated at 5 ºC for 2 hours. Following equilibration, semen parameters were analysed. Thereafter, the semen samples were loaded into straws and placed 5 cm above a liquid nitrogen vapour for 10 min, and then stored at -196 ºC until use. Following one month of storage, frozen semen straws per treatment group were thawed at 37 ºC for 30 seconds, then semen parameters were analysed again. Significant differences among the mean values of semen parameters were determined by Tukey’s test using ANOVA, GLM procedure of SAS version 12.1 of 2010. Total Spermatozoa motility rate of Bioxcell® (92.5±4.6), (68.2±13.5) and Triladyl® (94.9±5.5), (63.1±15.1) were significantly reduced (P < 0.05) following equilibration and freeze-thawing process, respectively on washed semen groups. Live and normal spermatozoa percentages were drastically reduced in Bioxcell® (5.2±4.9) and Triladyl® (6.9±8.6) washed semen groups, following freeze-thawing. There was a significantly lower number of spermatozoa with high mitochondrial membrane potential in non-washed semen extended with Triladyl® (68.7±26.8) compared to non-washed semen extended with Bioxcell® (49.8±20.1) following the freeze-thawing process. In conclusion, the freezing-thawing process did reduce the indigenous buck semen parameters irrespective of removal or non-removal of seminal plasma. However, Bioxcell® extender was found to be more suitable for preserving spermatozoa during equilibration and freezing/thawing process of buck semen.

In this thesis, different types of PVT (photovoltaic-thermal collectors) for three different farms in Europe will be studied, as part of the RES4LIVE project from the European Union’s Horizon 2020 Research and Innovation Action programme. A suitable renewable energy system will be proposed for each farm, considering the temperature range requirement and the climate conditions in each farm. In addition, three simulation tools that will be used, namely, WINSUN, Collector Energy Performance Tool (CEPT) and Scenocalc, will be evaluated and compared. The PVT systems combine the production of electrical and thermal energy. The combination of these two technologies can result in higher electrical efficiency due to the cooling effect of the fluid in the thermal part. Other technologies that form part of this study include the concentrating photovoltaic (CPV) and concentrated photovoltaic thermal (CPVT) systems. There are two types of flat PVTs, unglazed and glazed. The advantages and disadvantages of each system will be disclosed in the section on literature review. In addition, the operation of the concentrated collectors have been compared with the flat PVT collectors. Three simulation tools are being compared in this project and the most widely used tool is Scenocalc, the free tool supported by the European Commission. In the results section, the inputs for each simulation tool are explained, starting with the weather files that were taken at the same time for all the simulation tools so that the outputs could be compared. These results will be shown numerically for each farm and compared in tables and represented in graphs to decide which one is best for each location. The outcomes have shown that Scenocalc has a very different thermal result compared with the other tools in the case of the flat collectors. On the other hand, WINSUN has resulted to be a suitable simulating tool for a first approach to the production of the different technologies. In the case of CEPT, this program is best fitted for concentrated collectors since it takes into account both the thermal and electrical IAMs, whereas Scenocalc only considers the thermal IAMs.

One of the more important economic activities in the Altiplano region is raising livestock, the exploitation of cattle, sheep, and llamas which are raised and adapted to the conditions surrounding this activity. Livestock production plays a fundamental role in the economy of farming families by providing them products such as meat, milk, cheese, fiber, skins, and other products that each translate into monetary revenues. The present study was carried out in the community of "Chama 6 de julio," Ingavi Province, Department of La Paz, about 83 km. (51.6 miles) outside of La Paz at an elevation of 3,792 m. (12,440 ft.) above sea level. The annual precipitation is 370 mm. (14.6 inches) and average annual temperature is 12° C (53.6° F). The set objectives of this investigative work were: To evaluate the economic behavior of the livestock production (cattle, sheep, and llamas) at the small ranchers 14 level. To quantify in monetary units the structure of costs and revenues of livestock activity. To carry out a socio-economic analysis of the activity. The statistic parameters used were: measures of means, deviations, and percentages. Techniques used for gathering information include the following: semi-structured interviews, dynamic polls, dialogues, conversations, key informants, and direct observation. In studying the costs and revenues of livestock activity the conventional model of fixed and variable costs was used. The method utilized to evaluate the activity is an adaptation of the economic evaluation expressed by the indicating gauges Cost-Benefit Relationship (RBC) and Annual Investment Profitability (RI). 42 families dedicated to agricultural and livestock activity were involved in the study. They were functionally classified according to the number of cattle that they have on their land, a classification that resulted in four groups. The first group contained families possessing from 4 to 6 cattle; the second, from 7 to 9; the third, from 10 to 12; and the fourth, the families with 13 to 15 cattle. Also, the number of samples for each class was calculated to be 5 families. As livestock activity is the most important for families in this community, these families have most of their money invested in their herds, investments ranging from 73% to 86% of all their active livestock investments. The other 14% to 27% of their investment is in the livestock infrastructure, tools, materials, and equipment. The amount of land possessed by families in this community ranges from 8 to 40 hectacres (19.8 to 98.8 acres). The meat (cattle, sheep, and llama) is the most important product for commercial purposes. Accordingly, families from class IV achieved the highest production with 812 kg. (180.7 lbs) per year, followed by classes III and II. The lowest annual amount came from families grouped into class I with only 235 kg. (518 lbs). Another product of utmost importance after meat is cheese for which the families of class IV were those that had the highest annual production with 476 units, with an average weight of 0.6 kg (1.3 lbs). They were followed by families in classes III and I. Finally, the families in class II achieved the smallest output with 337 units. 69% to 79% of the total production of meat and cheese is destined for market. The families consume only 10% to 31% of what is produced. Variable costs represent 87.25% of the total expenses. On the other hand, fixed costs amount to only 12.73% of the total. Labor represents the greatest expense, reaching an average of 71.17% of the total expense. Relative to gross annual revenue, families in class IV reached the highest average numbers with 7,996.00 Bs. (Bolivianos). The lowest gross annual revenues correspond to those in class I with only 3,124.00 Bs. Classes III and II occupy intermediate positions between both former classes. Comparing the sources of gross annual revenue, cattle meat occupies the greatest portion with 40.81%. This is followed by cheese production, lamb, and llama meat with 30.84%, 23.30%, and 2.17% respectively. At the same time, cattle meat and cheese provide these farming families with 71.65% of their total gross annual revenue. The net annual revenues are positive only for families in classes IV and III with numbers at 312.00 and 156.00 Bs. On the other hand, classes II and I have negative net revenues at -3,039.00 and -2,455.00 Bs. The indicative Cost-Benefit Relationship (RBC) shows viability of the activity for families from classes IV and III with figures of 1.04 and 1.02. It is not as viable for families in classes II and I with numbers at 0.62 and 0.50. Estimates provided by the annual investment profitability (RI) are only satisfactory for those in classes IV and III with percentages of 4.6% and 2.13%. Unsatisfactory percentages result for classes II and I with -35.45% and -49.31%. According to the results obtained for the four classes, livestock activity carried out by farming families does not provide an acceptable profitability, even for families that have greater numbers of livestock (more than 12 cattle). It would be much less profitable for the families that have smaller herds of livestock.

In den Mischfutterrationen für Milchrinder wurde ein mittlerer Gehalt von Kupfer, Zink, Mangan und Selen ermittelt, der 2,5-fach über der Versorgungsempfehlung liegt. Neben den umweltrelevanten Konflikten dieser Praxis sind auch Versorgungsprobleme bei den Milchrindern aufgrund unerwünschter Interaktionen der Elemente nicht auszuschließen. In elf sächsischen Milchviehbetrieben wurden die Ursachen der Überversorgung untersucht und Vorschläge zur Optimierung der Spurenelementversorgung von Milchrindern erarbeitet. Dabei konnte die mittlere Kupfer-, Zink- und Selenkonzentration in den TMR um im Mittel 25 %, d. h. auf ein mittleres Versorgungsniveau der Tiere von 150 % der Versorgungsempfehlung reduziert werden. Das Heft fasst die Ergebnisse der Untersuchungen zusammen.

In ausgewählten Betrieben mit automatischen und konventionellen Melksystemen wurden die ökonomischen Ergebnisse des Betriebszweiges Milch (BZA), die Verfahrenskosten der Milchgewinnung sowie die Leistungsentwicklung und Produktqualität analysiert und ausgewertet. Die Gesamtkosten der AMS-Betriebe in der BZA lagen um mindestens 1,5 Ct/kg verkaufter Milch über denen konventionell melkender Betriebe. Der Einsatz von AMS in großen Betrieben rechnet sich ab einem Lohnniveau deutlich über 20 EUR je Arbeitskraftstunde. In kleinen Betrieben ist das Melken mit AMS günstiger als mit einem Melkstand. Die Analyse der Leistungskennzahlen zeigt, dass Handlungsbedarf zur Verbesserung der Eutergesundheit und Fruchtbarkeit besteht.

Development of transfrontier conservation areas (TFCAs) in southern Africa depends, among other, on the ability of stakeholders to find practical and sustainable solutions for wildlife‐livestock integration in the conservation landscape. Due to the presence of buffalo Syncerus caffer in most of the TFCAs in southern Africa, foot‐and‐mouth disease (FMD) has to be controlled in susceptible livestock species sharing the rangelands with wildlife. Conventional FMD control measures act as an additional burden on communal livestock producers and may hamper rural development and wildlife‐livestock integration even further. However, commodity‐based trade in the form of an integrated approach to the control of both food safety and disease risk along the entire beef value chain has been proposed as a more favourable alternative for ensuring market access for beef produced at the wildlife‐livestock interface. Such a non‐geographic based approach could allow for trade to continue despite high risk of FMD if appropriate disease risk and food safety measures are implemented by farmers and subsequent role players along the value chain and hence, could promote greater wildlife‐livestock compatibility. / The objective of the present study was to analyse beef production, health and trade systems of farmers at the wildlife‐livestock interface within foot‐and‐mouth disease (FMD) protection zones in order to identify challenges, risks and limitations that may limit compliance with proposed commodity‐based trade prerequisites as well as value chain participation. Based on the findings of this study a holistic, integrated approach is proposed at the village level that could be implemented to serve as an incentive for equitable participation by farmers whilst 1) addressing the risks and limitations of a farming system, 2) ensuring greater wildlife‐livestock compatibility, and 3) promote consistent market access by fulfilling the requirements of an integrated value chain approach based on commodity‐based trade standards. / A farming systems approach was used to investigate beef production, health and trade systems in FMD protection zones mainly within the Zambezi Region (ZR) of Namibia, which is situated within the KAZA TFCA (Kavango‐Zambezi Transfrontier Conservation Area), but also the Mnisi study area (MSA) in South Africa adjacent to the Great Limpopo Transfrontier Conservation Area (GLTFCA). A combined qualitative and quantitative approach was used to assess and describe farmers’ perceptions in selected study areas about beef production, trade, and wildlife conservation. Secondary data obtained from state veterinary services, the Meatco abattoir in Katima Mulilo, as well as previous studies were analysed and modelled to describe spatial‐temporal trends in trade as well as cattle distribution in relation to resource availability. / The results indicate that beef production systems in some of the most remote areas of the ZR as well as in the MSA resemble a typical low‐input low‐output production system, mainly due to the high level of risk farmers had to cope with and the limited opportunity to offset losses. The major challenges within livestock farming in all the areas studied were animal diseases, grazing competition, predation, stock theft and contact with wildlife, although the importance of each varied between study areas. Herd size effect in the MSA significantly explained the variation in attitude towards trade, production and management of cattle between farmers with below average and farmers with above average herd sizes. In the MSA, home slaughter contributed significantly more to direct household food security in households with larger herd sizes than in households with smaller herd sizes, and in the ZR farmers with smaller herd sizes were discouraged from participation in formal trade. / The attitudes and perceptions of farmers In the ZR towards wildlife and conservation often varied between survey areas as a consequence of the variation in the geophysical properties of the landscape, proximity to conservation areas, as well as the form of the interface with conservation areas. The perceived spatial‐temporal movement of buffalo varied between survey areas in the ZR. However, the frequency and nature of buffalo‐cattle interaction was generally high and intimate. Most farmers associated buffalo with risk of disease, especially FMD, but some were more concerned about grazing competition and the negative effect on husbandry practises. Farmers readily deployed traditional risk mitigation tactics in the form of kraaling at night and herding at day to control the movement of their animals and to reduce risks. Herding was found to be a potential strategy to specifically mitigate cattlebuffalo contact despite the lack of evidence that an overall strategic approach to herding exist. Although the majority of farmers in the ZR were in favour of conservation and its benefits, the negative impact of increasing wildlife numbers on farmers’ attitudes was an indication that the generally positive sentiment was changing and may in future deter conservation efforts. / Indications are that the cattle population in the ZR at its estimated density and distribution had reached the ecological capacity of the natural resource base in the ZR and animal performance and survival was therefore subjected to increased variability in resource availability linked to climate change. The cattle population’s existence at ecological capacity and the inability of farmers to offset the loss of condition in the dry season with supplementary feed were reflected in the changes in carcass quality and grades across seasons. However, there was sufficient forage produced in the ZR to sustain animal performance to some extent throughout the year, but those areas with surplus forage existed beyond the assumed grazing range around villages and perennial rivers where most cattle and wildlife concentrate. The future ability of farmers to access such underutilised grazing resources in order to strategically counter the negative consequences of climate change and growing wildlife numbers could be an important coping and risk management mechanism linked to commodity‐based trade and sustained animal quality. / Regular FMD outbreaks had a significant impact on the consistency with which the Meatco abattoir in the ZR operated between the years 2007‐2011, with negative consequences to both farmers and the abattoir itself. It was found that the formal trade system in the ZR discriminated against farmers with below average herd sizes, and that the disposition held by farmers with smaller herd sizes are most significant in areas further than approximately 55km away from quarantine camps. Vegetation type and possible contact with buffalo or previous FMD outbreaks in the area did not significantly affect market participation nor off‐take rates at a crush‐pen level in the ZR. The negative effect that distance from a quarantine station had on formal off‐take rate and the level of sales to Meatco at crush‐pen level, was the most significant in the winter months and crush‐pens situated beyond 55km from a quarantine station. The results indicate that the trade range of the Meatco abattoir was less than its trade threshold which contributed to its struggle to sustain throughput and profitability. / Finally the loss of income farmers experienced in both the ZR and the MSA during simultaneous FMD outbreaks in the year 2012 was quantified, as well as the impact it had on livelihoods in the ZR. A commodity‐based trade approach may have reduced the impact on farmers’ income significantly. However, we farmers are unable to comply with the proposed requirements for mitigating risk and ensuring food safety and quality in such communal systems in the absence of interventions to build the necessary capacity and awareness. It is recommended that at the wildlife‐livestock interface such as those investigated in this study, an integrated value chain approach to trade could serve as a catalyst to incentivise and enable farmer participation in holistic, integrated rangeland and livestock management practises that will promote conservation and rural development. / Thesis (PhD)--University of Pretoria, 2016. / The Institute for Tropical Medicine, Antwerp, Belgium / University of Pretoria / National Research Foundation of South Africa / Veterinary Tropical Diseases / PhD / Unrestricted

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