Thesis (M.Sc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2019 / Cattle herd productivity in the smallholder sector is generally low in South Africa (Mapiye et al., 2009) with cattle off-take rates being as low as 15% per annum (ARC, 2016). Among the leading causes of reduced productivity in smallholder herds is cattle mortality caused by diseases and parasites, especially ticks (Hesterberg et al., 2007). Ticks and the diseases they transmit have been identified as the major cause of widespread morbidity and mortality in cattle kept by smallholder farmers in the semi-arid areas of South Africa (Dold and Cocks, 2001; Mapiye et al., 2009) which results in poor animal welfare. Access to animal health infrastructure and technology can help reduce the problem of cattle diseases. The study was conducted to examine the impact of ARC’s Infrastructural Facility Scheme on the profitability of cattle farming and perceptions of smallholder cattle farmers. The study had four objectives; (i) to identify and describe the socio-economic characteristics of smallholder cattle farmers in Fetakgomo Municipality and Makhuduthamaga Municipality; (ii) to assess the perception of smallholder cattle farmers on the facilities provided by ARC in the study area; (iii) to determine and analyse the profitability of smallholder cattle farmers in the study area and (iv) to assess the effect of cattle farmers’ socio-economic characteristics on cattle farming profitability in the area. A total of 224 smallholder cattle farmers were interviewed, of which 124 farmers were beneficiaries and 100 were non-beneficiaries. The Purposive Sampling procedure was employed to determine the desired sample size in both the two Municipalities. The results showed that 55% of the smallholder cattle farmers were beneficiaries and 45% of the smallholder cattle farmers were non-beneficiaries out of the sample size. There were more male-headed households of the beneficiaries and more female-headed households of the non-beneficiaries. An analysis of the farmers’ socio-economic characteristics further showed that the majority of the smallholder cattle farmers prefer using family labourers or household labourers in their cattle farming. The results depict that beneficiaries of the Animal Health Wise Project used 76.2% of the family labour and 23.8% of hired labourers for beneficiaries whereas for the non-beneficiaries, it was v 68.7% of the family labour and 31.3% of hired labour. Using family labour helped in minimising costs of labour. Farmers were asked a set of Likert type scale questions about their perceptions on the project. The perception index score revealed that the smallholder cattle farmers had a negative perception of it as the index score was skewed to the left with the value being 0.428. Profitability was measured through Gross Margin Analysis. The Gross Margin Analysis revealed that the mean value of the total revenue and gross margin for the beneficiaries were bigger than non-participants. This was because beneficiaries tend to sell their cattle at a higher price compared to the non-participants. Furthermore, smallholder cattle farmers that are beneficiaries tend to use the infrastructure and through that, their cattle productivity is higher resulting in higher gross margin and total revenue compared to the non-participants. The Multiple Linear Regression Model was used to assess the effect of cattle farmers’ socio-economic characteristic on the gross margin of the farmers in the study area. The results revealed that only 3 variables were significant. The total herd size, project participation and access to the market were significant at 1% and all had a positive effect towards the gross margin. The study suggested that there should be more infrastructural facilities that are built in other municipalities. By so doing, smallholder cattle farmers will use the facilities to improve their herd productivity and also improve their cattle’s health status. It was also recommended that there should be some training based on the use of the cattle infrastructural facilities scheme so that farmers can use the facilities effectively. Key words: Smallholder Cattle Farmers, Perception, Animal Health Wise Project, Infrastructural Facilities. / Center of Collaboration on “Economics of Agricultural Research and Development”

Legal Protection of Animals, Focusing on Livestock and Furbearers The diploma thesis titled "Legal Protection of Animals, Focusing on Livestock and Furbearers" provides a comprehensive overview of current framework of the legal protection of animals in the Czech Republic. The thesis is divided into seven chapters and several sub-chapters. The initial chapters present information on the historical tendencies and philosophical bases of animal protection, as well as on the development of the perceiving of animals as subjects of law, which has over several centuries formed into our contemporary idea of an animal, its protection and legal standing. Crossing over from international and European legal sources, the thesis gradually shifts its focus on Czech legislature which has undergone marked changes over the last year, namely through the amendment 246/1992 Sb. aimed at eliminating animal abuse. Constituting a key aspect of the work, specific terminology is discussed in chapter 3. Terms such as animal or abuse are clarified consulting the law. As the title makes evident, the pivotal chapters of the thesis provide a more detailed delineation of the legal regulations concerning livestock and furbearers. Individual sub- chapters then discuss the particularities of their breeding, welfare, transportation...

This study was stimulated by a publication of Mr Mike Bosch (Bosch 2007) that Cereus jamacaru DC (Cactaceae) used by him on his farm is effective for gastrointestinal nematode control in livestock. This plant, widely known as Queen of the night, is a serious invasive weed. We evaluated this claim in in vitro assays and in vivo experiments in sheep experimentally infected with Haemonchus contortus and Trichostrongylus colubriformis. This is the first report of such an anthelmintic trial in livestock involving C. jamacaru. The first study was to repeat the farmer’s work under strictly controlled conditions. In vivo studies were conducted to determine the possible direct anthelmintic effects of C. Jamacaru on ovine gastrointestinal nematodes. Eighteen sheep were allocated to three groups and were infected with 4000 H. Contortus and 6000 T. Colubriformis infective larvae given in 3 divided doses over a period of three days. From day 0 until day 49 of the experiment, sheep were drenched once a week with fresh blended C. jamacaru plants with the core removed at the same (32.33 g/sheep) or double the dose (64.66 g/sheep) used by Mr Bosch. No negative effects of the double dose were observed during the period of the experiment. Faeces were collected twice a week for faecal egg count. Based on the in vivo experiments, C. Jamacaru was not effective in reducing H. Contortus and T. Colubriformis in sheep to the 70% reduction levels of the control treatments considered to be a useful reduction in FEC. Nevertheless, its in vivo activity was substantial at the higher dose and reduced the FECs by 65%. To investigate the matter further some additional experiments were carried out. Specimens of C. Jamacaru were collected and dried in the shade. For the phytochemical analysis and in vitro experiments, the dried material was milled to a fine powder, it was extracted with acetone and five fractions (hexane, butanol, water, chloroform and 35% water in methanol) were obtained by solvent-solvent fractionation. The chemical composition of the fractions and crude extract was analysed by thin layer chromatography using three solvent systems of varying polarity and pH. To detect the separated compounds, vanillin-sulphuric acid-methanol was sprayed on the chromatograms and heated at 110°C for optimal colour development. The antioxidant activity in plant extracts may influence the immune systems of animals and have an indirect effect. The antioxidant activity was therefore determined. For qualitative analysis of antioxidant activity, the 2,2, diphenyl-1-picrylhydrazyl (DPPH) assay on TLC plates was used as a test for the radical scavenging ability of the compounds present in the different extracts. In the DPPH qualitative analysis of antioxidant activity there were a number of antioxidant compounds present in some of the extracts and fractions but the activity appeared to be low. This observation was confirmed in the TEAC quantitative analysis of antioxidant activity. Even the fraction with the highest activity was about 8 times less active than trolox or ascorbic acid. It therefore appears that stimulation of the immune system by antioxidant activity does not explain the results found on the farm. The antibacterial and antifungal activities were determined against 4 bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa) and 3 fungi (Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans). The minimum inhibitory concentration (MIC) values for plant extracts varied from 0.04 to 2.5 mg/ml. E. coli was the most sensitive and the fungi were in general resistant to the extract and fractions. In general the activity was not very good, especially if the dosage in an aqueous system on the farm is considered. Antimicrobial activity also does not explain the results obtained. The nematocidal activity was evaluated by an egg hatch assay and larval development viability assay (LDVA) in vitro. The acetone extract inhibited egg hatchability and killed infective larvae of H. Contortus nematodes of sheep in a concentration-dependent manner. The percentage inhibition of egg hatching of the acetone extract and the butanol, chloroform, 35% water in methanol, hexane and water solvent-solvent fractions were 100%, 100%, 94%, 91%, 9% and 16%, respectively. The percentage inhibition of larval development of the acetone extract and chloroform, 35% water in methanol, hexane and water fractions were 93%, 84%, 49%, 85%, 31%, respectively. The chloroform fraction was significantly more active than all the other fractions (p<0.05). The extracts had in vitro activity against the nematodes. The activity was however much lower than the positive control, albendazole. It is disappointing that our results do not provide an explanation for the success obtained by Mr Bosch on his farm. Even if we do not understand how it works it may be useful to prepare suitable dosages (using low level technologies adaptable to rural conditions) for use by resource-poor rural communities where C. jamacaru occurs as an invasive weed. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Paraclinical Sciences / unrestricted

Blackflies (Diptera: Simuliidae) are major pests in the livestock and labour-intensive farming systems along the major rivers in South Africa. At present, blackflies are controlled with the larvicide Bacillus thuringienses var. israelensis (B.t.i.). As part of establishing an environmentally friendly and cost-effective Integrated Pest Management (IPM) program against blackflies, investigations were initiated to support the present blackfly-control strategy in South Africa. Emphasis was placed on potential predators and parasites of the blackflies’ aquatic stages. Questionnaires were presented to livestock farmers along the Vaal and Orange Rivers to determine public views concerning blackfly annoyance. Furthermore, blackfly populations at thirteen sites along the Orange River, twelve along the Vaal River and one site along each of two tributaries to the Vaal River, namely the Riet and Harts Rivers, were monitored seasonally for one year. The abundance of the aquatic stages of blackflies and potential predators on stones and vegetation in the river was determined using the 10-point visual ranking system of Palmer (1994) and the South African Scoring system (SASS 5), respectively. The abundance of algae as well as other environmental factors, namely water flow, water temperature and turbidity, were also monitored. Farmers who were contacted along both the Vaal and Orange rivers indicated that they experience severe blackfly problems during the summer months and that the majority of farmers were not aware of any products available that could protect their animals against blackfly attacks. The farmers also indicated that they were willing to be involved in blackfly research to improve this situation. Blackfly larvae and pupae were found in high abundance in both the Vaal and Orange Rivers. Simulium chutteri was the most abundant species in the Orange River and S. adersi in the Vaal River. In both the Vaal and Orange Rivers there was no significant correlation between immature blackfly abundance and water flow and turbidity. Water temperature also played a role in the seasonal build-up of blackflies in the winter months. The three most abundant algae classes were Bacillariophyceae, Chlorophyceae and Cyanophyceae. Cyanophyceae was the only algae group that had a negative correlation with blackfly immature abundance in the Orange River; this was not statistically significant. There were no negative correlations in the Vaal River. In both the Vaal and Orange rivers, blackflies were infected with Mermithidae nematodes and Microspora protozoans. In the Vaal River, the infection prevalence in natural conditions was the highest for Microspora and in the Orange River the highest for Mermithidae. The most important families of blackfly predators identified were Hydropsychidae and Gyrinidae. Hydropsychidae was the only family recorded in high abundance but this predator had no effect on abundance of immature blackfly. Gyrinidae gave a negative correlation with immature blackfly abundance; however, this was not significant. The biological control agents identified in this research need to be evaluated further for use in an IPM approach with the current control system, B.t.i. Copyright / Dissertation (MSc)--University of Pretoria, 2008. / Veterinary Tropical Diseases / unrestricted

Los escarabajos coprófagos (Coleoptera: Scarabaeoidea) son un grupo de insectos muy importante en términos de diversidad y biomasa en los pastos de la cuenca del Mediterráneo. A pesar de su importancia ecológica, los escarabajos coprófagos están amenazados por varios factores, entre los cuales se destacan los cambios en el manejo de la ganadería tradicional. El objetivo general de esta tesis fue evaluar los efectos del abandono de la ganadería, su extensificación y uso histórico de productos médico veterinarios sobre las comunidades de escarabajos coprófagos usando medidas de biodiversidad y cuantificando la capacidad de remoción de estiércol en un paisaje sub-montano de la provincia de Pesaro-Urbino (Italia). En este trabajo se colectaron un total de 156 936 individuos, pertenecientes a 58 especies de escarabajos coprófagos. Los resultados de este trabajo sugieren que el uso histórico de productos médico veterinarios tiene un impacto negativo y ubiquitario sobre todas las especies de la comunidad de estudio, llevando a un empobrecimiento de los ensambles y a una pérdida de abundancia y biomasa. No obstante se ha registrado el mantenimiento de la estructura de la comunidad. Estos resultados son corroborados igualmente cuando nos enfocamos en la diversidad funcional. En efecto, el uso histórico de productos médico veterinarios lleva a una pérdida en el número de roles funcionales dentro de la comunidad, sin embargo las abundancias se encuentran repartidas equitativamente dentro de cada nicho funcional. Todos estos efectos sobre la comunidad de escarabajos coprófagos debido al uso de productos médico veterinarios, al final quedan reflejados en una pérdida del 70% en la capacidad de remoción de estiércol, comparados con áreas donde estos productos no son aplicados. La extensificación de la ganadería está representada por áreas que tienen una intensidad de pastoreo muy baja, las cuales pueden ser consideradas como la primera etapa hacia el abandono completo. En este sentido, los resultados de este trabajo demuestran como una simple reducción de la carga ganadera lleva a efectos negativos sobre las comunidades de escarabajos coprófagos, registrando una disminución en la diversidad alpha y en el número de especies indicadoras. Esta disminución en la cantidad de recurso trófico tiene implicaciones sobre la composición de la comunidad, favoreciendo especies oportunistas cuya biología le permite evitar la competencia, como por ejemplo; especies cleptoparásitas o especies cuyas larvas tienen un comportamiento saprófago. Este “efecto filtro” (filter effect) debido a la disminución de la cantidad trófica, está confirmado por los resultados de diversidad funcional, en los cuales se registró una disminución en el número de nichos funcionales y una fuerte redundancia por la presencia de nichos funcionales muy similares entre ellos. Los efectos sobre la comunidad de escarabajos coprófagos en los sitios con baja carga ganadera reflejan finalmente una pérdida en la capacidad de enterramiento del estiércol del 30-40% respecto a las comunidades en áreas con una mayor carga ganadera. Los resultados de este trabajo muestran que en las áreas con abandono total de la ganadería se observó una disminución en el número de especies, en la abundancia y biomasa total, en el número de especies indicadoras, en la abundancia de las especies de gran tamaño y en las especies que no tienen un comportamiento de nidificación durante el periodo reproductivo. Sin embargo, el mantenimiento de una comunidad bien estructurada, subraya la importancia de dos factores locales: el excremento de la fauna silvestre y la mayor complejidad del hábitat debido a un proceso de invasión de árboles en el pasto. Este último factor es probablemente responsable de la presencia de especies indicadoras típicas de hábitats más cerrados como los bosques o matorrales. En cuanto a los resultados de diversidad funcional, estos confirman la interpretación del “efecto filtro” debido a la disminución en la cantidad de recurso trófico. En efecto, estos resultados muestran una unicidad funcional significativa en esta comunidad como consecuencia del fuerte cambio composicional que el abandono de la ganadería ha implicado, a pesar de una disminución en el número de nichos funcionales y en el mantenimiento de una buena estructura funcional. Así mismo, se registró una disminución en la capacidad de enterramiento del estiércol entre 27% y 47% respecto a las áreas con baja carga ganadera y con carga moderada por todos estos cambios cuali y cuantitativos en la comunidad de escarabajos coprófagos de los sitios abandonados. Se propone la ganadería ecológica como forma correcta de gestión de los pastos, la cual permitiría mantener un nivel de carga moderado, así como el control en uso de compuestos médico veterinarios.

El presente trabajo de investigación tiene como objetivo saber la incidencia de la exoneración del IGV de la leche cruda entera en los costos de producción y precio de venta de las empresas del sector ganadero lechero de Lima, año 2019. Para ello se ha dividido la investigación en 5 capítulos. En el capítulo I se encuentra el marco teórico, que nos permite conocer las opiniones y posturas de diversos autores y expertos en el tema que nos proporciona la base teórica de la investigación. En el capítulo II, tenemos el plan de investigación donde se detalla el problema principal, la justificación, los objetivos e hipótesis generales y específicas que se validan en el presente trabajo. En el capítulo III, se presenta la metodología de la investigación, también se define la muestra y los instrumentos a utilizar de acuerdo a la metodología elegida. En el capítulo IV, se realiza el caso práctico que busca mejorar la comprensión del tema, mostrando la realidad de una empresa que goza del beneficio de la exoneración. Asimismo, se desarrolla y presenta los resultados obtenidos de los instrumentos elegidos según la metodología empleada, en el caso de la presente investigación, las entrevistas a profundidad y las encuestas. Finalmente, en el capítulo V, se analiza los resultados obtenidos de los instrumentos cualitativos y cuantitativos utilizados, así como del caso práctico, con la finalidad de concluir con la validación de las hipótesis presentadas y establecer recomendaciones a las empresas del sector. / The objective of this research work is to know the incidence of the exemption of the IGV of the whole raw milk in the production costs and sale price of the companies of the dairy sector of Lima, year 2019. To this end, the research has been divided in 5 chapters Chapter I contains the theoretical framework, which allows us to know the opinions and positions of various authors and experts on the subject that provides us with the theoretical basis of the research. In Chapter II, we have the research plan detailing the main problem, the justification, the general and specific objectives and hypotheses that are validated in this work. In Chapter III, the research methodology is presented, the sample and the instruments to be used are also defined according to the chosen methodology. In Chapter IV, the case study is carried out that seeks to improve the understanding of the subject, showing the reality of a company that enjoys the benefit of exoneration. Likewise, the results obtained from the instruments chosen according to the methodology used are developed and presented, in the case of this research, in-depth interviews and surveys. Finally, in chapter V, the results obtained from the qualitative and quantitative instruments used, as well as the case study, are analyzed in order to conclude with the validation of the hypotheses presented and establish recommendations to the companies in the sector. / Tesis

Antibiotic Feed Additives (AFA) have been used to prevent many bacterial infections during weaning of livestock. The use of these AFA’s resulted in the development of multiresistant bacterial strains and was therefore banned by the European Union. The United States also restricted the use of these feed additives considerably. Many scientists have started to search for alternatives in the prophylactic and therapeutic treatment of bacterial infections. Plants have been used traditionally by resource poor people all over the world to treat many infections. Diarrhoea not only causes many problems in the high intensity production of livestock but also leads to many human deaths. A large number of plants have been used to treat diarrhoea in humans and animals. Several authors have selected one or two species based on traditional use to evaluate in depth. In this project several different relevant parameters of 53 plant species used traditionally to treat diarrhoea were investigated in order to develop a model that would identify the species with the highest chance of delivering a useful antibacterial product. Antibacterial activities against two pathogens important in diarrhoea (Staphylococcus aureus and Escherichia coli) were positive parameters in selecting species. Because tannins frequently have antibacterial activity, but are not useful as prophylactic agents due to their effect on production, high tannin content was considered to be a negative indication. Cellular toxicity was also used as a negative parameter at a later stage. In addition to the in vitro assays there are also other parameters to be investigated to evaluate the potential use of plants. The influence of season of collection was determined on the antibacterial activity and tannin content of acetone leaf extracts of five plant species traditionally used to treat diarrhoea. They were Acacia karroo, Acacia sieberiana var. woodii, Peltophorum africanum, Trichilia emetica and Ziziphus mucronata. The antibacterial activity varied depending on the season of collection with the best activity generally in the months of late summer to autumn (January to April). The activity of Acacia karoo against E. coli was best in the month of April (MIC = 0.11 mg/ml (TA = 332 ml/g)) and against S. aureus in the month of March (MIC = 0.06 mg/ml (TA = 334 ml/g)). Acacia sieberiana subsp. woodii extracts had the best activity against E. coli (MIC = 0.10 mg/ml (TA = 303 ml/g)) in March against S. aureus in April (MIC = 0.08 mg/ml (TA = 303 ml/g)). <i.Peltophorum africanum extracts were most active against E. coli in February (MIC = 0.05 mg/ml (TA = 1188 ml/g)) and against S. aureus in February and March (MIC = 0.04 mg/ml (TA = 1188 ml/g and 1075 ml/g)). Trichilia emetica extracts were generally not very active against the bacterial strains (best activity: MIC = 0.22 mg/ml (TA = 74 ml/g) against E. coli in May and MIC = 0.28 mg/ml (TA = 26 ml/g) against S. aureus in December). Ziziphus mucronata was most active against both bacterial strains and in May (E. coli: MIC = 0.10 mg/ml (TA = 589 ml/g); S. aureus: MIC = 0.04 mg/ml (TA = 1099 ml/g)). The tannin content varied in the extracts as well. The antibacterial activity however did not seem to be directly correlated to the tannin content. Another important parameter in the use of plant species is to determine the interspecies variation of plants based on genetic or environmental influences. Leaves from 42 plants of Combretum molle were collected at different locations during the same season. The average MIC against E. coli was 0.227 mg/ml. The low standard deviation of 0.07 indicates that there was very little variation in activity. The average value against S. aureus was 0.399 mg/ml with a slightly higher standard deviation of 0.16. However due to the fact that the samples from different areas extracted different amounts, the total activity varied. The tannin assays revealed that there was with one exception no correlation between the antibacterial activity and the tannin content. So it can be safe to assume that genetic variation does not influence the activity too much at least in C. molle leaves Fifty three plant species traditionally used to treat diarrhoea in published literature were then ranked using a novel system in order to determine which species had the most potential value. Ranking was based on the lowest MIC value against E. coli, lower activity against S. aureus (to limit selecting for general metabolic toxins), low tannin concentration and high extract yield. From this ranking, five plants were chosen to investigate their potential value further: Acacia sieberiana var. woodii (E. coli: MIC = 0.13 mg/ml, TA = 108 ml/g; S. aureus: MIC = 0.13 mg/ml, TA = 108 ml/g; Yield = 14 mg), Albizia adianthifolia (E. coli: MIC = 0.14 mg/ml, TA = 239 ml/g; S. aureus: MIC = 0.04 mg/ml, TA = 765 ml/g; Yield = 34 mg), Deinbollia oblongifolia (E. coli: MIC = 0.17 mg/ml, TA = 158 ml/g; S. aureus: MIC = 0.08 mg/ml, TA = 338 ml/g; Yield = 27 mg), Spirostachys africana (E. coli : MIC = 0.13 mg/ml, TA = 300 ml/g; S. aureus: MIC = 0.09 mg/ml, TA = 438 ml/g; Yield = 38 mg) and Tetradenia riparia (E. coli : MIC = 0.09 mg/ml, TA = 214 ml/g; S. aureus: MIC = 0.13 mg/ml, TA = 149 ml/g; Yield = 20 mg). None of the plants contained any tannin. The next step towards the recommendation of a plant for the development of a commercial product was to evaluate the cytotoxicity of the selected five species. The following values were obtained: Acacia sieberiana var. woodii LC50 = 0.026 mg/ml, Albizia adianthifolia LC50 = 0.068 mg/ml, Deinbollia oblongifolia LC50 = 0.078 mg/ml, Spirostachys africana LC50 = 0.025 mg/ml and Tetradenia riparia LC50 = 0.028 mg/ml. Deinbollia oblongifolia (for its low LC50 value) and Spirostachys africana (for its good antibacterial activity and total activity) were potentized by removing inactive compounds through solvent-solvent fractionation. The antibacterial activity against E. coli was increased this way (MIC = 0.08 mg/ml for Deinbollia oblongifolia (chloroform fraction) and MIC = 0.08 mg/ml for Spirostachys africana (chloroform fraction)) The LC50 values for both chloroform fractions were determined (LC50 = 0.188 mg/ml for Deinbollia oblongifolia and LC50 = 0.062 mg/ml for Spirostachys africana ). The selectivity index (SI) was also determined and proved that the potentization was indeed successful (Deinbollia oblongifolia SI = 2.35 compared to a value of 0.45 for the crude extract; Spirostachys africana SI = 0.78 compared to a value of 0.19 for the crude extract). Based on these values, the chloroform fraction of Deinbollia oblongifolia was chosen as the less toxic one with similar activity and a higher selectivity index to be worked on further. One of the active compounds was isolated and evaluated for its activity against E. coli (MIC = 0.74 mg/ml) The LC50 value of 0.042 mg/ml indicated that the activity of the extract was a result of synergism rather than being due to a single active compound (the selectivity index (SI) was 0.06 compared to the values of 0.45 for the crude and 2.35 for the potentized extract). The plant extracts should of course be as effective against pathogenic strains as they were against the ATCC strains and so the extracts and pure compound of Deinbollia oblongifolia were tested for their activity against four different pathological E. coli strains. The results showed that the crude extract and the fraction were as active as in the preliminary screening results against only one of the four pathological strains. The pure compound on the other hand was more active against all four pathological strains than against the ATCC strain. The next step was to test the safety of the extracts of Deinbollia oblongifolia in mammals. Unfortunately neither the crude extract nor the chloroform fraction of Deinbollia oblongifolia could be used safely in a living organism or in an isolated organ study. A part of the problem may have been caused by the vehicle used in the study despite reports in the literature that an acetone water mixture is safe to use. In general all the species investigated had good antibacterial activity against E. coli this supports the traditional use of these species although we used acetone as extractant rather than the water used traditionally. There were major differences in antibacterial activity over a season indicating that mature leaves were more active than young leaves before senescence started. At least in the case of Combretum molle there was little difference in the antibacterial activity of many plants collected at different locations during the same season. The results obtained in this study could be useful in further studies to develop extracts that can be used to control diarrhoea in animals. Possibly more emphasis should be put on the difference in activity towards E. coli and S. aureus to eliminate the presence of general metabolic toxins. Such an approach would lead to a different priority order for species to examine. A major first step would probably be to test the in vitro and in vivo toxicity of selected species. / Thesis (PhD)--University of Pretoria, 2010. / Paraclinical Sciences / unrestricted

Richtlinie 2003/99/EG des Europäischen Parlaments und des Rates legt das Ziel für die Mitgliedsstaaten fest, ein Monitoring von Antbiotikaresistenzen bei Zoonoserregern zu implementie-ren. Da die Menge verabreichter antimikrobieller Wirkstoffe im direkten Zusammenhang mit der Entwicklung von Resistenzen steht, impliziert diese Richtlinie auch die Menge der in Nutztierbeständen eingesetzten antimikrobiellen Wirkstoffe zu erfassen und zu überwachen. Zielsetzung dieser Arbeit war es, im Rahmen des Projekts VetCAb die Möglichkeiten der Datenerhebung von Verbrauchsmengen von Antibiotika bei landwirtschaftlichen Nutztieren aus gesetzlich vorge-schriebenen Nachweisen (Tierärztlicher Anwendungs- und Abgabebeleg nach §13 TÄHAV, Bestandsbuch nach ANTHV) in Tierarztpraxen bzw. landwirtschaftlichen Betrieben zu untersuchen und hinsichtlich pharmakologischer Parameter zu bewerten. Am Projekt VetCAb (Veterinary Consumption of Antibiotics) nahmen 24 tierärztliche Praxen aus fünf Landkreisen Niedersachsens (Cloppenburg, Diepolz, Emsland, Nienburg, Vechta) sowie 66 landwirtschaftliche Betriebe im Landkreis Kleve (Nordrhein-Westfalen) freiwillig teil. Daten vom Zeitraum eines Jahres (01. September 2006 – 31. August 2007) wurden erfasst und in einer zentralen Datenbank abgelegt. Für die Auswertung standen zudem epidemiologische Daten zur Vieh- und Betriebsdichte (Easystat® 2007) sowie weitergehende Informationen der zuständigen Veterinärämter der betroffenen Landkreise (HEGGER-GRAVENHORST 2010, MOLLENHAUER 2010) zur Verfügung. Insgesamt wurden 74.427 Datensätze erhoben, von denen ein Anteil von 4,18 % (entsprechend 3.114 Datensätze) als nicht-plausibel gekennzeichnet war. 68.565 Datensätze entstammten dabei der Erhebung in Praxen, 5,862 der in landwirtschaftlichen Betrieben, was einem geometrischen Mittel von 2743 Datensätzen pro Praxis bzw. 58 pro landwirtschaftlichen Betrieb entspricht. Im Rinder- als auch im Schweinebereich wurden Tetracycline mit rund 50 % der verbrauchten Mengen am häufigsten eingesetzt, β-Lactame lagen dabei auf dem zweiten Rang. Bezüglich der Betrachtung der Zahl der Einzelgaben war eine Abnahme des Verbrauchs von Tetracyclinen zu-gunsten eines Anstiegs von Makroliden und Trimethoprim (inclusive Trimetoprim/Sulfonamide) zu verzeichnen. Bezüglich des Einsatzes von Antiinfektiva wurden die Diagnosegruppen Atemwegserkrankungen (69,21 % beim Rind, 58,86 % beim Schwein, Geflügel 34,90 %) und Darmer-krankungen (4,57 % beim Rind, 14,91 % beim Schwein, Geflügel 50,12 %) am häufigsten angegeben. Die Darreichung auf oralem Wege stellte mit 81,20 % der eingesetzten Gesamtmenge beim Rind, 94,24 % beim Schwein und 99,34 % beim Geflügel die häufigste Applikationsform dar (v.a. Tetracycline, β-Lactame, Makrolide oder Sulfonamide). Im Vergleich der eingesetzten Dosierung mit der festgelegten Richtdosierung (mg/kg) lagen beim Rind bzw. Schwein insgesamt 23,10 % bzw. 23,73 % unter, 36,13 % bzw. 47,31 % über und 44,77 % bzw. 28,95 % innerhalb der Richtdosierung. Mit der im Projekt VetCAb durchgeführten Untersuchung zur Durchführbarkeit und Etablierung eines Verbrauchsmengenmonitorings in der Nutztierhaltung konnten grundlegende Erkenntnisse aufgezeigt werden, wobei Aspekte der Datenerfassung, der Pharmakologie, der Epidemiologie und der arzneimittelrechtlichen Rahmenbedingungen berücksichtigt wurden. Die Möglichkeiten überstiegen darüber hinaus die im Arzneimittelgesetz in § 47 Abs. 1b und DIMDI - Arzneimittel-verordnung dargelegten Anforderungen eines Antibiotikaverbrauchsmengenerfassungsprogramms, welches lediglich die Verkaufszahlen antimikrobieller Wirkstoffe auf Seiten des pharmazeutischen Unternehmers erfassen kann und damit keine Rückschlüsse auf den Antibiotikaeinsatz bei der jeweiligen Zieltierart gezogen werden können. Im Projekt Vet-CAb wurden die Verbrauchsmengen des freien Wirkstoffs getrennt nach Tierarten und Alters- bzw. Nutzungsrichtungen sowie nach Art der Applikation bei landwirtschaftlichen Nutztieren erfasst. Ferner kann das Dosierungsverhalten durch das Festsetzen von Richtdosen abgeleitet werden. Zudem besteht die Möglichkeit tagesaktuelle Verbrauchsmengen über eine online verfügbare Datenbank abzufragen. Aufgrund der zahlreichen Auswertungsmöglichkeiten ist das Er-fassungssystem in der Lage wissenschaftlich fundierte Daten über den Antibiotikaverbrauch bei landwirtschaftlichen Nutztieren zu liefern, die als sinnvolle Ergänzung zu Resistenzmonitoring-Systemen betrachtet werden können. Auch eine Vergleichbarkeit der erfassten Verbrauchsmen-gen mit den Daten aus Verbrauchsmengenmonitoringprogrammen anderer europäischer Länder ist gegeben. Vorraussetzung hierfür ist eine Festlegung standadisierter Auswertungsparameter für die europäischen Länder. Diese Vergleichbarkeit der Datenströme und der Ausbau vergleichbarer Arzneimittelklassifikationssysteme ist als Bestandteil präventiven Risikomanagements (PASCH et al. 2005, HELMUTH und HENSEL 2006) ein erstrebenswertes Ziel. In der vorliegenden Machbarkeitsstudie konnte gezeigt werden, dass das untersuchte Konzept diesen Anforderungen prinzipiell genügt und auch zukünftigen Anforderungen an eine Verbrauchsmengenerfassung von Antibiotika bei landwirtschaftlichen Nutztieren aus wissenschaftlicher Sicht standhalten kann.

Zur Klimagestaltung in Legehennenställen werden primär Unterdrucklüftungssysteme mit einem Luftwechsel nach dem Strahllüftungsprinzip entlang der Querachse des Stalls eingesetzt. Zur besseren Frischluftversorgung im Tierbereich werden zunehmend Unterdrucklüftungssysteme mit einem Luftwechsel nach dem Tunnelprinzip entlang der Längsachse des Stalls eingesetzt. Im Projekt werden die beiden Luftwechselvarianten verglichen, um Kenndaten zu ausgewählten Stallraumlasten sowie zum Luft- und Volumenstrom für die Varianten zu bestimmen und hieraus Bewertungen zu Staub-, Geruchs- und Ammoniakemissionen abzuleiten. Die Ammoniakemissionen sind bei der Tunnellüftung gegenüber Strahllüftung niedriger, die Staubemissionen sind dagegen bei der Strahllüftung geringer. Für die Geruchsemissionen wurden keine Unterschiede festgestellt. Die Voliereblöcke erzeugen im Stallraum Strömungsbarrieren und werden von der Frischluft weitgehend umströmt. Hierdurch entstehen deutliche Luftwechselunterschiede zwischen dem frei durchströmbaren Stallraum und dem Innenbereich der Voliereblöcke.

In sächsischen Schweinehaltungsbetrieben wurde ein objektives Bewertungssystem zur Tierhygiene und Tiergesundheit entwickelt und erprobt. Aus zahlreichen Untersuchungen in den Produktionseinheiten Ferkelerzeugung, Ferkelaufzucht, Jungsauenaufzucht und Mast resultieren Kennziffern zur Hygiene, Klinik und Gesundheit, die einen Vergleich verschiedener Bestände erlauben. Sie lassen stufenübergreifend auch eine Bewertung einzelner Produktionseinheiten zu. Mit regelmäßigen Untersuchungen ist zudem der zeitliche Verlauf der Kennziffern und damit des Hygiene- und Gesundheitsstatus möglich.