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Broiler production in Ghana and Senegal : farm economics, international competitiveness and policy considerations
(2023) Chibanda, Craig Chikomborero; Wieck,Christine
Chicken meat consumption has rapidly increased in many West African countries in the last three decades. The increase in consumption has been attributed to several factors, which include population growth, urbanization, rising incomes, and the nutritional importance of chicken meat. However, poultry producers in many West African countries were struggling to meet the rising demand. Consequently, the gap in supply and demand led to an increase in frozen poultry meat imports by many African countries at the end of the 1990s. Most of the imports consisted of chicken meat cuts, which were considerably cheaper than domestically produced chicken meat. Price-wise, domestic chicken meat could not compete with imports, which sparked debate over their importation. In West African nations such as Ghana, Senegal, and Ivory Coast, farm closures, income losses, and a precipitous decline in domestic poultry production are believed to have resulted from the imports' low prices. In the early 2000s, countries in the region reacted differently to the influx of low-priced chicken imports, with some countries instituting protectionist measures that halted the imports while others continued to import the low-priced frozen chicken meat as a means of providing their citizens with a source of affordable animal protein. Although there has been much debate about the various pathways that countries have taken, limited research has been conducted to compare the agronomic and economic status quo of broiler chicken production in countries with different policies. Against this backdrop, the overarching objective of this dissertation is to investigate the economics and international competitiveness of broiler production in two West African countries pursuing different poultry trade policies: Ghana (which is heavily reliant on chicken meat imports) and Senegal (which banned poultry meat imports for almost two decades).
Five research gaps in the body of literature on broiler production in Ghana and Senegal are identified in this dissertation. First, existing studies classify broiler production in Ghana and Senegal into broad production systems that are ambiguous. Second, although a number of studies have been conducted on the Ghanaian broiler value chain, there are conflicting arguments regarding the reasons for its lack of development. Third, existing studies do not provide comprehensive analyses of the performance (management), cost structure, and profitability of different broiler farm types in Ghana and Senegal. Fourth, there are no existing studies that compare the international competitiveness of broiler farms in West African countries like Ghana and Senegal with those in key chicken meat exporting countries. Fifth, the current body of literature fails to adequately examine some policy-related concerns. Specifically, little consideration is given to the potential effects of implementing alternative poultry trade policies in Ghana on producers. Based on these research gaps, this dissertation attempts to answer three overarching research questions:
i. What is the state of broiler farm economics and broiler value chains in Ghana and Senegal?
ii. How does the competitiveness of broiler farms in Ghana and Senegal compare with those in key chicken meat exporting countries in Europe (i.e., Germany and the Netherlands)?
iii. What are the potential effects of implementing alternative poultry trade policies in Ghana?
As this is a cumulative dissertation, the research questions were addressed in a series of journal articles that are included in this dissertation as chapters 2, 3, 4, 5, and 6.
Chapter 2 characterizes and analyses the economics of broiler production systems in Ghana. The typical farm approach is used for this purpose. This approach entails constructing empirically grounded farm data sets that are called “typical farms” through the use of a multi-stakeholder workshop, semi-structured interviews, and focus groups. Three broiler production systems in three regions were identified. They include the large-scale integrated production system (> 20,000 birds/year) in the Ashanti (Kumasi) region, the medium-scale system (5,000–20,000 birds/year) in the Brong-Ahafo (Dormaa) region, and the small-scale commercial system (< 5,000 birds/year) in the Greater Accra region. The Technology Impact Policy Impact Calculations (TIPI-CAL) model was then used to determine the performance, costs of production, and profitability of typical farms. TIPI-CAL is a production and accounting model used for farm economic analysis as it allows a detailed examination of farm-level variables and simulations. The findings presented in Chapter 2 show that the typical small-scale farm is performing the least in comparison to the other farm types in the country in terms of feed conversion ratios (FCR) and Broiler farm economy index (BFEI). The low farm performance of the typical small-scale farm is attributed to the use of poor-quality feed, inappropriate husbandry practices, and its long feeding period. Small-scale producers in Ghana attribute the unusually long feeding period (around 63 days) to market competition from low-priced frozen chicken meat imports. The producers explained that instead of selling their chickens in 42 days they had to rear them for up to 63 days because there is no ready market for them. The findings also show that although the typical medium-scale and large-scale integrated farms are generally performing better than the small-scale farm, they are also not performing so well in terms of the expected performance levels. Furthermore, the results show that broiler production in Ghana is typically seasonal. The seasonal production was attributed to the competition from frozen chicken meat imports, which are cheaper and more readily available in cut pieces, making preparation easier than with domestic chickens that are typically sold live. The results of the farm economic analysis also show that feed and day-old chick (DOC) costs are the most significant production cost items for all three typical farms. Despite the relatively high costs of feed and DOCs, broiler production as a seasonal activity is profitable for all typical farms.
Chapter 3 studies the performance of Ghana’s poultry value chain and examines the interlinked challenges that actors in the value chain are facing and their underlying causes. The Sustainable Food Value Chain (SFVC) framework is used to assess and develop strategies to sustainably upgrade the Ghanaian broiler value chain. The SFVC concept moves away from the traditional approach of value chain analysis, where well-known constraints are listed along with proposed recommendations. Instead, the concept takes a universal perspective to identify the interlinked foundational causes of why value chain actors fail to take advantage of existing end-market opportunities. Due to the complex nature of studying value chains, both qualitative and quantitative research methods are employed. These include focus groups, semi-structured interviews, desk reviews, and the Delphi method. The results of the study highlight the poor economic, social, and environmental performance of the Ghanaian poultry sector. Although the results of the Delphi study show that poultry experts in Ghana perceive imports and high feed costs as the most significant challenges facing the value chain, a deeper analysis reveals that weak vertical and horizontal coordination among actors in the value chain, coupled with low commitment from supporting stakeholders, emerge as the root causes of the value chain's challenges. To achieve sustainable growth, the Ghanaian poultry value chain requires commitment and support from the government and other stakeholders, as well as coordination between them. The study also explains that effective vertical relationships (e.g., trust and communication) will play a vital role in the process of upgrading the value chain by promoting conditions that encourage investment. Also, effective cooperation in the horizontal linkages, for example, among producer associations (especially for the many small-scale producers), would contribute to reducing their production costs while facilitating their access to buyers and processors. In addition, competitive improvements would result in more value-added domestic chicken products that cater to the growing demands of Ghanaian consumers at lower prices.
Chapter 4 studies the state of broiler production in Senegal after nearly two decades of poultry import restrictions. It provides a synopsis of the Senegalese broiler value chain and evaluates the performance and economics of different farm types. A multi-stakeholder workshop and interviews were conducted with key informants to investigate the structure and activities of the Senegalese broiler value chain. Again, the typical farm approach was used to construct and analyze typical farms that represent the most common broiler production systems in Senegal. Small-scale (<10.000 birds/year), medium scale (10,000–100,000 birds/year), and large-scale integrated (> 100,000 birds/year) production systems were identified as the most prevalent broiler production systems. The findings show that the two typical medium-scale broiler farms in Senegal are performing well in terms of FCRs, BFEI, and mortality rates. The good performance is attributed to the use of high-quality inputs (feed and chicks) and good husbandry practices. The results of the value chain analysis suggest that the country has well-developed feed and hatchery industries. Therefore, the development of these industries has ensured that producers have access to domestically produced, high-quality inputs. Nevertheless, the typical small-scale farm is not performing well, and this is attributed to inappropriate poultry husbandry practices. Additionally, the analysis revealed that feed and day-old chick (DOC) costs are the most significant in conventional broiler production in Senegal. Despite the high costs of feed and DOCs, broiler production is profitable for all typical farms.
Chapter 5 examines whether differences in the competitiveness of broiler farms in Ghana, Senegal, Germany, and the Netherlands provide insight into why domestically produced chicken meat in West African countries is more expensive than imports from Europe. For this comparison, farm management (none monetary farm performance indicators) and economic performance indicators (costs of production and profitability) of typical broiler farms in the four countries are derived. The study shows that most of the typical broiler farms in Ghana and Senegal are not competitive with farms in Germany and the Netherlands in terms of farm management. More specifically, the findings show that the typical German and Dutch broiler farms are performing better than all typical farms in Ghana and the typical small-scale farm in Senegal in terms of the FCRs, BFEI, mortality rates, and number of production cycles per year. However, the performance of typical medium scale farms in Senegal is almost comparable to that of German and Dutch farms in terms of all the farm management indicators that were analyzed. The good farm management of medium scale farms in Senegal is attributed to good animal husbandry practices and the use of high-quality feed and high-quality DOCs. The findings also show that typical broiler farms in Ghana and Senegal are not competitive with German and Dutch farms in terms of economic performance. The poor economic performance of the Ghanaian and Senegalese farms is attributed to higher production costs. Apparently, the broiler farms in the two countries have higher production costs due to high feed and DOC costs. In Ghana, high feed costs are attributed to high feed prices and feed-use inefficiency (reflected by high FCRs). In the case of Senegal, high feed costs are largely due to high feed prices. Having established that typical broiler farms in Ghana and Senegal are not competitive in terms of farm management and costs of production , the impact of improving farm management (primarily the FCRs) on production costs was then simulated using the TIPI-CAL model. The results of the simulations demonstrate that improving farm management to optimum levels would lead to a reduction in the costs of production for Ghanaian and Senegalese farms. However, the reduction would not be sufficient to make the farms competitive with those in Germany and the Netherlands because high input costs (feed and DOC) are the primary contributors to high production costs. Improving the competitiveness of broiler farms will therefore require a combination of interventions designed to lower input costs and enhance farm management.
For decades, Ghanaian policymakers have been pressured to implement protectionist policies to protect the poultry value chain from low-priced imports. Chapter 6 examines the potential impact of implementing these policies. The Modular Applied General Equilibrium Tool (MAGNET) and TIPI-CAL models are used to examine the: (1) potential impact of a hypothetical complete ban of poultry meat imports in Ghana; (2) potential impact of a partial ban of poultry products (banning poultry products originating from the UK, Germany, the Netherlands, Denmark, and Russia); (3) potential effects of raising the import tariffs on poultry meat in Ghana to 40 percent and 99 percent; and (4) potential effects of abolishing the current 5% import tariff rate on maize imports. The results show that a complete ban on poultry meat imports would have a positive impact on domestic poultry meat production, increasing production by 254%. This increase will be most likely driven by existing farms doubling their production cycles and new producers attracted to a protected broiler sector. The findings also show that a complete ban would increase the importation of maize. Considering the importance of maize for poultry production in Ghana, the effects of abolishing the existing 5% import tariff rate on maize were simulated. The results show that removing the tariff would not lead to a significant increase in poultry production. This is most likely due to the fact that the tariff rate is already very low. In accordance with World Trade Organization (WTO) agreements, Ghana is allowed to increase the tariff rate on poultry meat up to 99% (the maximum level of bound tariff). The findings show that increasing the tariff rate from the current 35% to 99% would result in a 104% increase in domestic poultry meat production. The tariff would offer significant protection to domestic producers and result in a significant reduction in poultry meat imports (around 57% reduction in imports). The typical farm analysis indicates that broiler farms in Ghana are more prevalent in urban and peri-urban areas. Therefore, a boost in domestic poultry meat production would most likely lead to an increase in urban and peri-urban employment. The findings also show that medium- and large-scale farms employ the highest number of people; therefore, such farm types are expected to boost urban and peri-urban employment if they increase production. Also, of importance, an increase in domestic broiler production will most likely have positive knock-on effects on other value chain actors such as slaughterhouses, feed millers, and poultry traders. Although the results indicate that producers will benefit from the implementation of protectionist measures, it is important for policymakers to keep in mind that such measures will most likely also have negative implications. For example, the results show that protectionist measures would lead to a decrease in the Gross domestic product (GDP) as the measures would either reduce or eliminate the imports leading to reduced tariff revenues, which account for a large share of total tariff revenues in Ghana.
The dissertation concludes that a comprehensive sector-wide policy-making approach that considers all the challenges facing the different value chain actors (e.g., hatcheries, feed millers, producers, traders, slaughterhouses and consumers) will be more effective in providing a delicate balance that ensures that the broiler value chains in Ghana and Senegal develop and consumers have access to affordable chicken meat. Such an approach would also be useful in addressing the issue of high input prices (mainly feed and day-old chicks), which is at the center of the low competitiveness of broiler farms in the two countries. Additionally, the comprehensive policy-making approach should also consider the need for proper infrastructure and technology to support the growth of broiler value chains. This includes investments in cold storage facilities and slaughterhouses to ensure efficient and cost-effective processing and distribution of chicken meat. By addressing these challenges holistically, policymakers can create an enabling environment for the development of sustainable and competitive broiler value chains in both countries.
Subtitling vs. dubbing and original version : the effects of different translation methods on consumer behavior towards product placement on audiovisual content
(2024) Noschang, Luis Octávio; Vogelgesang, Jens
The main objective of this dissertation was to investigate whether different versions of a program concerning audiovisual translation formats as well as multitasking would influence product placement effectiveness on audiences. Also, if there would be any relation between levels of multitasking and the version of the program being watched. The first problem to be addressed was determining whether the above-mentioned questions have not been the subject of research in the past. A systematic search on the three most prominent research databases available (Scopus, Web of Science, and EBSCO) followed by a manual analysis of the publications was conducted and research items of these publications were further investigated to identify effects caused by placements as well as variables or drivers of product placement effectiveness.
Some 320 research items (hypotheses, research questions, empirical generalizations, and results) featured effects caused by placements. The total of effects identified was 11. Brand attitude and brand recall were the two most prominent effects identified. In the case of variables, or drivers of effectiveness, 417 research items included 57 different variables that could be divided into 2 categories: 33 variables derived from characteristics of the audience and 24 variables pertaining to the content, medium, or placement. None of the publications featured audiovisual translation formats as variables, confirming the research gap in the field. For multitasking, 2 publications were identified that covered the subject, nevertheless, in a different form than the intended of this dissertation.
The empirical investigation was performed through an experiment where participants could freely choose between four options of pre-defined episodes of two different sitcom series as well as the version between original, dubbed, and subtitled, the last only as a choice for those
that could not understand the spoken dialogues. Some 2302 participants were recruited and answered a questionnaire containing questions about aided recall of brands placed in the
episode, and multitasking behavior while watching the program.
Results on brand recall of placements remained constant between groups watching different versions of the programs. Punctual percentual differences could be identified, nevertheless, reversed results appeared for different products, and Chi-square tests revealed no statistically
significant differences. The presence of subtitles did not significantly alter brand recall. Brand recall also remained stable among viewers of programs in original, dubbed, and subtitled versions.
Results compared brand recall of placements between viewers who declared that they engaged in other activities while watching the program and viewers who did not multitask. The levels of brand recall did not differ significantly between these two groups.
The time spent not looking at the screen was the next aspect evaluated in the experiment. Here, no significant difference in the levels of brand recall was identified between the viewers who did not look at the screen for less than 1 minute and the viewers who looked away from the screen for between 1 and 5 minutes during programs of around 20 minutes in length.
The different versions of the program were tested with regard to their influence on multitasking behavior. The presence of subtitles decreased viewers’ levels of multitasking when compared with those of viewers who watched the program in its original or dubbed versions with no subtitles added to enhance comprehension of the spoken dialogues. The levels of multitasking remained constant between viewers of the dubbed and original versions of the program.
To increase the validity of the results, a method of observing the respondents was also implemented. A total of 274 respondents were recorded in videos that were later analyzed manually. This method was introduced to more precisely determine the time they spent not looking at the screen as well as to detect false positives on the respondents’ answers.
Molecular regulation of components of root development and nutrient uptake in white lupin (Lupinus albus L.)
(2023) Olt, Philipp; Ludewig, Uwe
White lupin (Lupinus albus L.) is specially adapted to sites with low availability of plant-available phosphorus (P), which is of particular agricultural importance because of chemical P fixation in the soil and limited reserves of P fertilizer resources. With special root structures, the cluster roots (syn. proteoid roots), it considerably increases the root surface area and excretes root exudates such as anions of organic acids, which make it possible to release phosphate ions from poorly soluble phosphate compounds in the soil and make them available to plants. The characteristic structure of these cluster roots usually consists of a lateral root with certain sections that have a significantly higher density of further lateral roots (rootlets) than the rest of the lateral root. In addition, the rootlets are evenly limited in length and, as they grow bundled in the cluster sections, the structure of cluster roots is reminiscent of a bottle brush. Cluster roots are also formed by other plant species such as some species from the Proteaceae family, but in contrast to these slow- growing and perennial woody plants, white lupin with its short life cycle and small size is an ideal model organism for the study of these special root structures. In addition to the mechanisms involved in the function of cluster roots, the regulation of formation and development of cluster roots is also of great importance for basic research in this field. Three studies were carried out as part of this thesis to examine these aspects in more detail.
In order to better understand the functional mechanisms involved in the excretion of exudates, the hypothesis that the METAL AND TOXIN EXTRUSION (MATE) transport proteins LaMATE and LaMATE3 transport citrate was tested in the first study. The similarity of the gene sequences of these white lupin proteins with proteins from the MATE/DTX family, of which citrate transport is already known, as well as the increased gene expression of LaMATE and LaMATE3 in mature cluster roots led to this assumption. However, electrophysiological studies of the proteins with 13C- labeled citrate showed that LaMATE and LaMATE3 probably do not transport citrate and also the analysis of root exudates from transient loss-of-function mutants could not confirm the involvement of LaMATE in the transport of citrate. However, the excretion of the isoflavonoid genistein was found to be significantly reduced in the transient loss-of-function mutants, leading to the hypothesis that LaMATE may be involved in the exudation of isoflavonoids in mature cluster roots.
As a result of the mobilization of phosphates through the excretion of organic acids, other cations such as manganese (Mn) also dissolve, which leads to increased Mn concentrations in the soil solution. As manganese uptake in the roots is not actively regulated, Mn accumulates in the plant, which has a toxic effect in higher concentrations. For this reason, white lupin needs a strategy to counteract toxic manganese accumulation, which was investigated in more detail in the second study. The observation that a greater increase in Mn concentration could be measured in the leaves than in the roots after elevated Mn exposure of white lupin indicates an actively regulated transport of excess Mn in the plant. The METAL TOLERANCE PROTEIN (MTP) AtMTP8 is involved in the detoxification of excess Mn in Arabidopsis and the increased gene expression of the corresponding white lupin homolog LaMTP8.1 in plants exposed to elevated Mn concentration suggested that LaMTP8.1 also fulfills a detoxification function. In further experiments, the ability of the LaMTP8.1 protein to transport Mn was demonstrated by heterologous expression of LaMTP8.1 in yeast cells. Furthermore, the high Mn concentrations in the leaves already indicated that the sink of Mn sequestration is located there and since AtMTP8 transports Mn into the vacuole, it was assumed that LaMTP8.1 could be localized in the tonoplast of the leaf cells to transport excess Mn into the vacuoles. This hypothesis was confirmed by homologous expression of LaMTP8.1 combined with a fluorescent marker in white lupin protoplasts. In summary, this study demonstrated that LaMTP8.1 is a vacuolar Mn transporter that mediates the transport of Mn into the vacuoles of leaf cells to detoxify excess Mn.
While the first two studies addressed functional and physiological aspects of cluster roots, the third study focused on the mechanisms of formation and development of these root structures. To this end, the main focus was on the CLAVATA3/ EMBRYO SURROUNDING REGION (ESR)- RELATED (CLE) peptide family, of which some members regulate root growth in other plant species and enable more precise control of regulation compared to the known growth regulators auxin and cytokinin. In a comprehensive analysis, 30 known and further 25 new, putative CLE peptides were identified in Lupinus albus. Several of the CLE peptides were tested in a hydroponic system on young white lupins for their effects on root development and cluster root formation. The two CLE peptides LaCLE35 (RGVHyPSGANPLHN) and LaCLE55 (RRVHyPSCHyPDPLHN) showed striking inhibitory effects and altered both root growth and cluster root development in an inhibitory manner. The peptide LaCLE35 stood out in particular because it was the only CLE peptide detected in white lupin xylem sap and was therefore investigated in more detail. It was shown that LaCLE35 influences both the density and the length of cluster rootlets, and thus has an effect on the two crucial factors of cluster root formation. The inhibitory effect of CLE35 could be attributed to a suppression of cell elongation and further experiments with split-root setups showed that the externally added synthetic peptide LaCLE35 has a local but not a systemic effect.
The investigations of the LaMATE transport proteins and LaMTP8.1-mediated Mn detoxification as well as the overview of the detected CLE peptides in white lupin and the analysis of the inhibitory influences of LaCLE35 on cluster roots form the basis of this thesis and aim to contribute to the understanding of the function, effects and formation of these special root structures.
Sentiment and institutional investors
(2023) Klingler, Linda; Gehde-Trapp, Monika
Institutionelle Investoren, in dieser Arbeit vertreten durch US-Fondsmanager, sind ein wichtiger Teil des globalen Finanzsystems, und ihr Verhalten hat Auswirkungen auf das Vermögen der Fondsanleger. Außerdem sind sie anfällig für Verhaltensverzerrungen und Sentiment. In dieser Dissertation analysiere ich daher die Beziehung zwischen Sentiment und Fondsmanagern aus verschiedenen Blickwinkeln empirisch. Ein Schwerpunkt liegt auf demografischen Merkmalen der Fondsmanager und wie diese ihre Reaktion auf bestimmte Umstände beeinflussen. Diese Umstände bilden den zweiten Schwerpunkt dieser Arbeit: Das Sentiment. In zwei Kapiteln wird untersucht, wie Fondsmanager auf die Stimmung reagieren, die auf Marktebene durch den bekannten Volatilitätsindex VIX gemessen wird. Das letzte Kapitel wechselt die Perspektive und betrachtet die in Aktionärsbriefen ausgedrückte Stimmung auf der Ebene der einzelnen Fondsmanager und wie Fondsanleger auf diese Stimmung reagieren.
Kapitel 2 befasst sich mit möglichen Unterschieden zwischen männlichen und weiblichen Fondsmanagern in ihren Reaktionen auf die Marktstimmung. Die Ergebnisse zeigen, dass weibliche Fondsmanager bei schlechter Stimmung weniger unsystematisches Risiko eingehen als ihre männlichen Kollegen. Außerdem führt das höhere unsystematische Risiko, das männliche Fondsmanager eingehen, nicht zu einer besseren Performance, sodass die Fondsanleger keinen Ausgleich für das höhere Risiko erhalten. In Kapitel 3 analysiere ich die Auswirkungen der Kultur auf das Verhalten von Fondsmanagern und konzentriere mich auf das Bedürfnis nach Sicherheit, das ein Fondsmanager an den Tag legt. Fondsmanager mit einem hohen Sicherheitsbedürfnis gehen weniger unsystematisches Risiko ein als Fondsmanager mit einem geringen Sicherheitsbedürfnis. Da bei der Analyse das Geschlecht und andere demografische Merkmale berücksichtigt werden, ist Kultur ein anderes Element der erhöhten Risikobereitschaft aufgrund schlechter Stimmung. Auch hier hat dieser Unterschied in der Reaktion keine Auswirkungen auf die Performance. Kapitel 4 ändert die Art und Weise wie Sentiment gemessen wird. Mein Mitautor und ich konzentrieren uns auf die (durch Negativität ausgedrückte) Stimmung in Aktionärsbriefen, die von männlichen und weiblichen Fondsmanagern verfasst wurden, und analysieren, wie die Fondsanleger darauf reagieren. Wir stellen fest, dass sich männliche und weibliche Fondsmanager in ihren Briefen unterscheiden und dass das Geschlecht eine wichtige Determinante der Negativität ist. Darüber hinaus bestrafen Fondsanleger weibliche Fondsmanager stärker für zunehmende Negativität, nicht aber ihren männlichen Kollegen. Bei weiblichen Fondsmanagern gehen die Mittelzuflüsse zurück, bei männlichen Fondsmanagern kann keine Reaktion der Fondsanleger beobachtet werden. Da der geschlechtsspezifische Tonfall keine signifikante Vorhersagekraft für die künftige Fondsperformance hat, ist eine geschlechtsspezifische Voreingenommenheit der Fondsanleger eine wahrscheinliche Erklärung für unsere Ergebnisse.