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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The handling of undated pig embryos and foetuses as a prelude to histological studies of morphogenesis in the oral region

van Rensburg, Barend. Gabriel January 1976 (has links)
Magister Chirurgiae Dentium (MChD) / The author is interested in the morphogenesis of the oral region including the nasopalatine complex. With the intention of undertaking a study of the· embryological development in this area, perusal of available literature failed to reveal a single compreh.ensive description of the reception and handling of embryonic and foetal material, mensuration and preparation for miscroscopy. Human material for embryological study is relatively scarce in· the Republic of South Africa. According to the literature there is, however, a distinct similarity between human and domestic pig development in certain regions, notably the palate. Furthermore, pig embryos and foetuses are available in comparative abundance from sows slaughtered at abattoirs. As a consequence of the above-mentioned factors it was,decided to undertake a -preparatory study in order to firstly evaluate existing methods of handling of embryonic and foetal material and secondly, to statistically evaluate data relating to mass and measurements.'· The aim was to draw a comparison with existing information and to select a sample for investigation. Embryos and foetuses were removed from slaughtered sows in a fresh state and removed to the laboratory immersed in 10 per cent neutral buffered formol saline. In the laboratory foetal membranes were removed, umbilical cords cut and the specimens weighed. They were then placed in Bouin's solution for final fixation and decalcification. Instruments were designed to measure crown-tailroot length, crown-rump length and dorsal profile length. After one day in Bouin's solution all specimens were measured. In order to determine the accuracy of the weighing and measuring procedures ten fixed specimens were weighed and measured on seven consecutive days. Statistical analysis of this data indicated that crown-rump length was the most accurately determinable linear measurement, judged by both the coefficient of variation and the standard deviation. On this basis crown-rump length was chosen as the criterion for selecting the sample to be studied. Correlation between linear measurements and between linear measurements and mass for the entire series showed a very strong positive relationship between all the parameters indicating that a dimensional relationship was maintained during growth. After measuring, the small specimens were embedded whole while larger embryos and foetuses were decapitated. A method was described for trimming and embedding these heads in such a way that subsequent sectioning would take place in a standardised transverse plane. In larger specimens this procedure had to be delayed until demineralization had taken place. Conclusions based on a consideration of data for the entire population included the following: 1. The mean number of specimens per litter was 6,475. 2. The number of pigs per litter stayed relatively constant throughout the period of gestation. 3. Mass showed a greater intra-litter variation than any of the three linear measurements recorded. 4. Relatively, lengths appeared to vary less in older than in younger Ldtt.ers-, irrespective of litter size
12

Exploring the valorization of porcine hemoglobin through its peptic hydrolysis and the production of bioactive peptides

Sanchez Reinoso, Zain 16 August 2024 (has links)
Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2023 / Le sang d'abattoir est un sous-produit de valeur pour l'industrie de la viande, car de nombreux composés bioactifs peuvent en être dérivés. Sa fraction solide (cruor) se compose principalement d'hémoglobine (Hb), duquel une bonne source de peptides antimicrobiens et antioxydants qui peuvent être libérés par hydrolyse pepsique. Cette approche présente un grand potentiel pour l'industrie de la viande en raison du marché croissant des ingrédients bioactifs naturels et de leur utilisation potentielle pour la biopréservation des aliments. En effet, cette approche a été largement étudiée sur l'hémoglobine bovine (Hb-B), suivant un concept d'économie circulaire dans lequel les peptides bioactifs sont réutilisés pour conserver les produits carnés. Néanmoins, cette alternative de valorisation fait face à quelques défis tels que l'exploration d'autres sources importantes d'hémoglobine comme l'hémoglobine porcine (Hb-P), l'optimisation du processus d'hydrolyse, et la validation de ses propriétés bioactives afin d'obtenir une application à plus fort impact sur la durabilité de l'industrie de la viande. Dans ce contexte, il est nécessaire d'explorer à la fois de nouvelles sources d'hémoglobine et de nouvelles alternatives technologiques pour sa valorisation et son application de manière plus éco-efficiente. Ainsi, l'objectif principal de ce projet de recherche était d'évaluer la faisabilité de l'obtention de peptides antimicrobiens et antioxydants pour la biopréservation alimentaire à partir d'Hb-P par hydrolyse pepsique et traitements par champs électriques pulsés (CÉP), qui a été divisée en trois étapes principales. La première étape visait à établir les meilleures conditions pour l'hydrolyse pepsique de l'Hb-P et établir les similitudes avec la principale source de peptides antimicrobiens identifiés à ce jour (Hb-B). Par conséquent, au cours de cette étape a évalué l'influence du pH (pH 2, 3, 4 et 5) a été évaluée sur l'activité antimicrobienne et la population de peptides des hydrolysats pepsiques dérivés de Hb-P en comparaison avec Hb-B. Des similarités dans la population peptidique entre les hydrolysats d'Hb-B et d'Hb-P ont été observées, principalement lors de l'hydrolyse enzymatique à pH 2 et 3. Les hydrolysats bovins et porcins produits à pH 2 et 3 ont montré une activité antibactérienne contre *Listeria ivanovii* (CMI = 0,62 - 1,25 mg/mL) et une activité anti-levure contre *Rhodotorula mucilaginosa* (CMI = 0,31 - 1,25 mg/mL). À l'inverse, seule une activité antifongique contre *Mucor racemosus* dans l'hydrolysat de porc à pH 3 a été observée (CMI = 1,25 mg/mL). Cette étude a confirmé les similitudes de l'Hb-B et de l'Hb-P en termes de profils peptidiques et d'activité antimicrobienne, ce qui indique que l'Hb-P est également une source appropriée de peptides antimicrobiens ayant des activités antibactériennes, antifongiques et anti-levures. Après avoir étudié les possibilités d'améliorer les conditions de l'hydrolyse pepsique conventionnelle de l'Hb-P, l'utilisation de technologies non conventionnelles pour améliorer le processus enzymatique a aussi été explorée. Une deuxième étude a été menée pour évaluer l'impact des CÉP sur l'inactivation de la pepsine dans les hydrolysats d'Hb-P et d'Hb-B, caractériser les populations de peptides après l'inactivation de la pepsine par les CÉP, et évaluer les effets du traitement CÉP et du pH final (3, 7 et 10) sur les activités antimicrobiennes et antioxydantes des hydrolysats finaux. Dans ce cas, l'Hb-B et l'Hb-P ont été hydrolysées par la pepsine dans les conditions optimales établies précédemment (37 °C à pH 3,0 pendant 3 h) et traitées par CÉP (73 impulsions, 23,8 kV/cm, 90 Hz) pour inactiver l'enzyme. Le degré d'hydrolyse (DH) qui a été évalué, n'a montré aucun changement significatif après l'inactivation de la pepsine par les CÉP, alors que l'analyse de la population peptidique par RP-UPLC-MS/MS a mis en évidence quelques changements dans les hydrolysats traités par les CÉP au fil du temps, suggérant une activité résiduelle de la pepsine. Les traitements par CÉP n'ont pas montré d'impact significatif sur les activités antimicrobiennes (antibactériennes, antifongiques et anti-levures). Cependant, un pH final plus élevé (pH 10) a favorisé une plus forte activité anti-levure (*R. mucilaginosa*), tandis qu'un pH de 7 a favorisé l'activité antifongique (*M. racemosus*). Malgré certains changements observés dans la population de peptides, aucun effet positif ou négatif des CÉP n'a été constaté sur les activités antimicrobiennes et antioxydantes. Après l'évaluation des alternatives pour améliorer l'hydrolyse enzymatique de l'Hb-P, une troisième étape a été réalisée pour explorer les possibilités d'application des hydrolysats d'Hb-P dans le contrôle des microorganismes alimentaires indésirables tels que les organismes pathogènes d'origine alimentaire. Cette étape consistait à évaluer et à comparer la faisabilité d'utiliser des hydrolysats peptidiques dérivés de Hb-P et de cruor porcin (P-Cru) comme stratégie de biocontrôle de *Listeria monocytogenes* dans les produits carnés. À cette fin, des hydrolysats peptidiques ont été préparés à partir de Hb-P et de P-Cru à différentes conditions de température d'hydrolyse et de rapport enzyme/substrat (E/S). Ensuite, l'activité antimicrobienne (*in vitro* et *in situ*) des hydrolysats a été évaluée sur trois sérotypes différents de *L. monocytogenes*. Il a été établi que la réduction de la température et du rapport E/S de l'hydrolyse du P-Cru a affecté le rendement enzymatique, entraînant deux unités de pourcentage de moins de DH par rapport à l'hydrolysat d'Hb-P, ainsi que quelques différences dans la population de peptides. Cependant, l'activité antimicrobienne (*in situ*) n'a pas été affectée de manière significative, diminuant le nombre viable de *L. monocytogenes* de ~1-log et retardant sa croissance pendant 21 jours à 4 °C. Cette étude a prouvé, pour la première fois, la faisabilité de la production d'un agent de biopréservation pour le contrôle de *L. monocytogenes* dans un produit carné prêts-à-manger (PAM) à partir de cruor de porc comme une alternative pour la valorisation du sang d'abattoir dans une approche d'économie circulaire. En résumé, ce projet de recherche a confirmé que, comme l'Hb-B, l'Hb-P est une source appropriée pour la production de peptides antimicrobiens et antioxydants par hydrolyse pepsique. De plus, la faisabilité technologique de l'utilisation des traitements de CÉP pour arrêter l'hydrolyse enzymatique pendant la production de peptides bioactifs dérivés de l'hémoglobine a été validée. Enfin, l'utilisation potentielle des hydrolysats de Hb-P pure et de P-Cru pour la biopréservation des produits carnés PAM contre *L. monocytogenes* a été démontrée. / Slaughterhouse blood is a valuable by-product of the meat industry since multiple bioactive compounds can be derived from it. Its solid fraction (cruor) consists mainly of hemoglobin (Hb), a good source of antimicrobial and antioxidant peptides that can be released by peptic hydrolysis. This approach has great potential for the meat industry due to the growing market for natural bioactive ingredients and their potential use in food biopreservation. Indeed, this approach has been extensively studied on bovine hemoglobin (Hb-B), following a circular economy concept in which bioactive peptides are reused to preserve meat products. Nevertheless, this valorization alternative faces some challenges such as the exploration of other important sources of hemoglobin such as porcine hemoglobin (Hb-P), optimization of the hydrolysis process, and validation of its bioactive properties in order to achieve a higher impact application for the sustainability of the meat industry. In this context, it is necessary to explore both new sources of hemoglobin and new technological alternatives for its valorization and application in a more eco-efficient way. Thus, the main objective of this research project was to evaluate the feasibility of obtaining antimicrobial and antioxidant peptides for food biopreservation from Hb-P through peptic hydrolysis and pulsed electric fields (PEF) treatments, which was divided into three main stages. The first stage aimed at establishing the best conditions for peptic hydrolysis of Hb-P and establish the similarities with the main source of antimicrobial peptides identified to date (Hb-B). Therefore, this stage evaluated the influence of pH (pH 2, 3, 4, and 5) on the antimicrobial activity and the peptide population of peptic hydrolysates derived from Hb-P and compared in parallel with Hb-B. Similarities in the peptide population between Hb-B and Hb-P hydrolysates were observed, mainly in the enzymatic hydrolysis at pH 2 and 3. Both bovine and porcine hydrolysates produced at pH 2 and 3 showed antibacterial activity against *Listeria ivanovii* (MIC = 0.62 - 1.25 mg/mL) and anti-yeast activity against *Rhodotorula mucilaginosa* (MIC = 0.31 - 1.25 mg/mL). Conversely, only antifungal activity against *Mucor racemosus* in the porcine hydrolysate at pH 3 was observed (MIC = 1.25 mg/mL). This study confirmed the similarities of Hb-B and Hb-P in terms of peptide profiles and antimicrobial activity, which indicates Hb-P is also a suitable source of antimicrobial peptides with antibacterial, antifungal, and anti-yeast activities. Having studied the opportunities to improve the conditions of conventional peptic hydrolysis of Hb-P, the use of non-conventional technologies to improve the enzymatic process was also explored. A second study was conducted to evaluate the impact of PEF on pepsin inactivation in hydrolysates of Hb-P and Hb-B, characterize the peptide populations after pepsin inactivation by PEF treatment, and assess the effects of PEF treatment and final pH (3, 7, and 10) on the antimicrobial activities of the final hydrolysates. In this case, Hb-B and Hb-P were hydrolyzed with pepsin under the optimal conditions previously established (37 °C at pH 3.0 for 3 h) and treated with PEF (73 pulses, 23.8 kV/cm, 90 Hz) to inactivate the enzyme. The degree of hydrolysis (DH) was also evaluated, which did not show significant changes after PEF-inactivation of pepsin, whereas the peptide population analysis by RP-UPLC-MS/MS showed some changes in PEF-treated hydrolysates over time, suggesting a residual pepsin activity. PEF treatments did not show any significant impact on antimicrobial (antibacterial, antifungal, and anti-yeast activities). However, higher final pH (pH 10) fostered stronger anti-yeast activity (*R. mucilaginosa*), whereas pH 7 fostered antifungal activity (*M. racemosus*). Even though some changes were observed in the peptide population, no positive or negative effects of PEF were found for the antimicrobial and antioxidant activities. Upon evaluation of the alternatives for improving the enzymatic hydrolysis of Hb-P, a third stage was carried out to explore the opportunities for the application of Hb-P hydrolysates in the control of undesirable food microorganisms such as food-borne pathogens. This stage consisted of evaluating and comparing the feasibility of using peptic hydrolysates derived from Hb-P and porcine Cruor (P-Cru) as a strategy for biocontrol of *Listeria monocytogenes* in meat products. For this purpose, peptic hydrolysates were prepared from Hb-P and P-Cru at different conditions of hydrolysis temperature and enzyme/substrate (E/S) ratio. Then, the antimicrobial activity (*in vitro* and *in situ*) of hydrolysates was compared against three different serotypes of *L. monocytogenes*. As a result, it was established that the reduction of temperature and E/S ratio of P-Cru hydrolysis affected the enzymatic performance, resulting in two percentage units less DH compared to Hb-P hydrolysate, as well as some differences in peptide population. However, the antimicrobial activity (*in situ*) was not significantly affected, decreasing the viable count of *L. monocytogenes* by ~1-log and retarding its growth for 21 days at 4 °C. This study proved, for the first time, the feasibility of producing a biopreservative for the control of *L. monocytogenes* in a ready-to-eat (RTE) meat product from porcine cruor as an alternative for the valorization of slaughterhouse blood under a circular economy approach. To summarize, this research project has confirmed that, similar to Hb-B, Hb-P is a suitable source to produce antimicrobial and antioxidant peptides through peptic hydrolysis. Also, the technological feasibility of using PEF treatments to stop enzymatic hydrolysis during the production of hemoglobin-derived bioactive peptides has been validated. Furthermore, the potential use of both pure Hb-P and P-Cru hydrolysates as biopreservation of RTE meat products against L. monocytogenes has been demonstrated.
13

La série Aux Abattoirs de la Villette (1929) : le point de vue du photographe Eli Lotar par-delà la revue Documents et la philosophie de Georges Bataille

Lesage, Émilie 09 1900 (has links)
Ce mémoire étudie la série Aux Abattoirs de la Villette photographiée par Eli Lotar en 1929. Il montre comment elle a été assimilée par l’histoire de l’art au texte « Abattoir » de Georges Bataille, aux côtés duquel ont été reproduites trois photos du corpus sous la rubrique Dictionnaire critique de la revue Documents. Cette emprise théorique sur la série est mise en perspective au regard de la démarche artistique d’Eli Lotar et des autres photomontages dont elle a fait l’objet ensuite. Le premier chapitre insiste sur la formation d’Eli Lotar et introduit son séjour à La Villette en lien avec la thématique de l’abattoir dans l’entre-deux-guerres. Il analyse ensuite la fortune critique d’Aux Abattoirs de la Villette qui s’appuie sur la philosophie de l’informe chez Georges Bataille. Le deuxième chapitre analyse le photomontage de la série fait par E.L.T. Mesens dans Variétés (1930) et le photoreportage reconstitué par Carlo Rim dans Vu (1931). Selon des points de vue et un travail formel différents, tous deux accentuent la dimension humaine de l’industrie d’abattage animal. Le troisième chapitre fait apparaître le regard posé par Eli Lotar sur le site de La Villette en tenant compte de ses préoccupations socio-artistiques à travers ses collaborations auprès de Germaine Krull et Joris Ivens. Finalement, il dresse une analyse comparative de la série avec la toile Abattoir d’André Masson, le poème Porte Brancion de Raymond Queneau et le film Le sang des bêtes de Georges Franju pour renforcer les spécificités du médium photographique. / This master’s thesis is a study of the whole series Aux Abattoirs de la Villette, photographed by Eli Lotar in 1929. It demonstrates how the thirty-four prints were merged into Georges Bataille’s philosophy by the art historians of the 1990’s who based their interpretations upon the text « Abattoir ». This was published under the heading Dictionnaire critique inside Documents magazine. The series is taken apart from Bataille’s purpose in light of Lotar’s preoccupations and of the other editions of the photographs during the inter-war period. The first chapter insists on Eli Lotar’s photographic education preceding his visit to La Villette’s site in context with the slaughterhouse’s topic in the art Avant-garde. Then, it evaluates Aux Abattoirs de la Villette’s critical review based on Bataille’s conceptions of formless and sacrifices. The second chapter analyses the authorship conferred to the photomontages carried out by E.L.T. Mesens in Variétés (1930), who accentuates the similarities between the photographic and the slaughter cutting operations, and by Carlo Rim in Vu (1931), who reveals the human dimension of La Villette’s industry. The third chapter focuses on Lotar’s social preoccupations by according an importance to his collaborations with Germaine Krull and Joris Ivens. Finally, the series is addressed in an "intermediatic" perspective to emphasize the photographic point of view by comparing it with the painting Abattoir by André Masson, the poem Porte Brancion by Raymond Queneau and the film Le sang des bêtes by George Franju.
14

La série Aux Abattoirs de la Villette (1929) : le point de vue du photographe Eli Lotar par-delà la revue Documents et la philosophie de Georges Bataille

Lesage, Émilie 09 1900 (has links)
Ce mémoire étudie la série Aux Abattoirs de la Villette photographiée par Eli Lotar en 1929. Il montre comment elle a été assimilée par l’histoire de l’art au texte « Abattoir » de Georges Bataille, aux côtés duquel ont été reproduites trois photos du corpus sous la rubrique Dictionnaire critique de la revue Documents. Cette emprise théorique sur la série est mise en perspective au regard de la démarche artistique d’Eli Lotar et des autres photomontages dont elle a fait l’objet ensuite. Le premier chapitre insiste sur la formation d’Eli Lotar et introduit son séjour à La Villette en lien avec la thématique de l’abattoir dans l’entre-deux-guerres. Il analyse ensuite la fortune critique d’Aux Abattoirs de la Villette qui s’appuie sur la philosophie de l’informe chez Georges Bataille. Le deuxième chapitre analyse le photomontage de la série fait par E.L.T. Mesens dans Variétés (1930) et le photoreportage reconstitué par Carlo Rim dans Vu (1931). Selon des points de vue et un travail formel différents, tous deux accentuent la dimension humaine de l’industrie d’abattage animal. Le troisième chapitre fait apparaître le regard posé par Eli Lotar sur le site de La Villette en tenant compte de ses préoccupations socio-artistiques à travers ses collaborations auprès de Germaine Krull et Joris Ivens. Finalement, il dresse une analyse comparative de la série avec la toile Abattoir d’André Masson, le poème Porte Brancion de Raymond Queneau et le film Le sang des bêtes de Georges Franju pour renforcer les spécificités du médium photographique. / This master’s thesis is a study of the whole series Aux Abattoirs de la Villette, photographed by Eli Lotar in 1929. It demonstrates how the thirty-four prints were merged into Georges Bataille’s philosophy by the art historians of the 1990’s who based their interpretations upon the text « Abattoir ». This was published under the heading Dictionnaire critique inside Documents magazine. The series is taken apart from Bataille’s purpose in light of Lotar’s preoccupations and of the other editions of the photographs during the inter-war period. The first chapter insists on Eli Lotar’s photographic education preceding his visit to La Villette’s site in context with the slaughterhouse’s topic in the art Avant-garde. Then, it evaluates Aux Abattoirs de la Villette’s critical review based on Bataille’s conceptions of formless and sacrifices. The second chapter analyses the authorship conferred to the photomontages carried out by E.L.T. Mesens in Variétés (1930), who accentuates the similarities between the photographic and the slaughter cutting operations, and by Carlo Rim in Vu (1931), who reveals the human dimension of La Villette’s industry. The third chapter focuses on Lotar’s social preoccupations by according an importance to his collaborations with Germaine Krull and Joris Ivens. Finally, the series is addressed in an "intermediatic" perspective to emphasize the photographic point of view by comparing it with the painting Abattoir by André Masson, the poem Porte Brancion by Raymond Queneau and the film Le sang des bêtes by George Franju.
15

Une géographie de la viande au Tamil Nadu (Inde) : statuts, espaces et circulations / Geography of meat in Tamil Nadu (India) : significations, spaces and circulations

Bruckert, Michaël 11 December 2015 (has links)
L’augmentation présumée de la consommation de viande en Inde, pays parfois décrit comme étant principalement végétarien, nourrit de nombreuses spéculations. Cette thèse vise à étudier les recompositions du statut de la viande en Inde, notamment dans l’Etat du Tamil Nadu, en accordant une attention particulière à la dimension spatiale de cet aliment. En Inde, la viande reste marginale : sa consommation est régulée par des logiques religieuses, morales, médicales ou économiques. Ses réseaux d’approvisionnement sont structurés par des contraintes écologiques et techniques mais aussi sociales et symboliques. Les abattoirs sont des lieux de conflit sur les usages et les significations des produits carnés. La visibilité des boucheries dans l’espace public est fortement contrôlée. Ainsi, la viande, notamment celle de bœuf, devient un aliment politique, support de revendications identitaires. Mais l’urbanisation, l’industrialisation et la connexion à l’espace-Monde modifient progressivement le rapport des Indiens à la viande. La massification des circuits carnés ne peut être niée. Les exportations de viande de buffle s’envolent. Au restaurant, la consommation de viande, notamment de poulet produit de façon intensive, devient pour la classe moyenne de Chennai une pratique statutaire. Pour autant, la transition alimentaire parfois prophétisée apparaît être une hypothèse erronée. La banalisation de la viande, circonscrite dans l’espace, va de pair avec une extrême différenciation des pratiques, en fonction des types de viandes, des individus, des contextes. En Inde, le rapport à la viande, véritable « substance biomorale », contribue à dessiner des géographies matérielles et idéelles, façonnant des territoires et des circuits, définissant des distances réelles ou symboliques entre les hommes et les animaux ou entre les groupes sociaux. / The fact that meat consumption is allegedly on the rise in India, a country often depicted as primarily vegetarian, feeds speculation. By paying special attention to the spatial dimensions of this foodstuff, this thesis aims at investigating the recasting of the meanings of meat in this country, particularly in the State of Tamil Nadu. In India, meat consumption is still marginal. Its consumption is religiously, morally, medically and economically regulated. Ecological, technical, social and symbolic constraints shape its networks of provision. The uses and significations of the different meats are contested in slaughterhouses. In the public space, the visibility of butcheries is under strict control. Thus, the issue of meat, and especially of beef, is highly negotiated within the political arena, being leveraged by identity claims. But dynamics of urbanization, industrialization and globalization appear to be gradually reconfiguring the relation that Indians maintain with meat. Undeniably, meat is becoming commoditized, mass-produced. Buffalo meat exports are soaring. At the restaurant, the consumption of meat, especially of intensively reared chickens, becomes a marker of social status for the middle classes of Chennai. Yet, the assumed food transition turns out to be a flawed assumption. The secularization and growing acceptance of meat is restricted to peculiar places. Practices are highly differentiated by types of meat, by individuals and by contexts. In India, the way people interact with meat, an actual “biomoral substance”, contributes to drawing material and immaterial geographies, to shaping territories and circuits, to fixing real and symbolic distances between people and animals and between social groups.
16

Evaluating traceability systems within the South African sheep meat supply chain

Van der Merwe, Melissa 24 May 2013 (has links)
One of the latest trends in the market for food products is the desire amongst consumers to know the origin of the products they purchase and to feel physically or emotionally connected to the farm and the producer. However, given the many efforts by producers and retailers to mislead consumers about the origin of products, for consumers to have faith in the origin of food products, they need to have some guarantee about the true origin of products. Thus, to be able to successfully guarantee the origin of food products, traceability systems need to be in place and they need to comply with the necessary legislation. This consumer need for origin-based food is now playing out in a variety of ways as food processors and retailers are labelling their products according to the origin of the product. Quite often, regional names are used for that identification. One iconic South African example of a product with regional identity is Karoo Lamb. In July this year producers from the Karoo region launched Karoo Lamb, a certification scheme, with a chain-wide traceability system in place to guarantee the Karoo origin of sheep meat in South African retail stores. The question, though, is whether all abattoirs and meat processors in South Africa are able to deliver origin-guaranteed products. The key factor here is the traceability system they have in place. The general objective of this study is therefore to assess current traceability systems in the sheep meat industry and to establish their ability to guarantee the origin of a carcass. This traceability system should be able to protect, manage and govern the food of origin attributes of a product in the sheep meat industry. The specific objectives of the study are: i) to create a high level process map to indicate the flow of Karoo Lamb products; ii) to share information by developing a detailed description of current and potential traceability systems in the Karoo Lamb supply chain; iii) to identify critical control points for maintaining product information and to test if these systems are in line with best practices; iv) to investigate the decision-making factors impacting on the implementation of a traceability system; and v) to develop recommendations for effectively implementing a traceability system that protects, manages and governs food of origin attributes. In response to these objectives, five hypotheses were developed and tested. The five hypotheses basically aimed to identify the tipping factor in the traceability implementation decision-making process. The population of South African sheep slaughtering abattoirs was used to draw a random sample of 55 abattoirs selected to participate in the research survey by means of interview administrated, structured questionnaires. The data was then processed and analysed to include a combination of quantitative and qualitative analysis. The results obtained by the research indicate that 92 % of the abattoirs in South Africa have proper traceability systems in place that enable them to market and deliver origin-guaranteed products. The 3 (8 %) abattoirs that do not have traceability systems are in the Northern Cape and Eastern Cape. This might become problematic, since sheep from these regions are often marketed as Karoo lamb. Without proper traceability systems, this credence attribute cannot be guaranteed. According to the hypothesis test, the fact that an abattoir delivers to a retailer is the single most significant factor, compared to the other factors tested, for abattoirs to implement a traceability system. Research showed that 95 % of retail delivering abattoirs have traceability systems in place, and the other 5 % of abattoirs are those situated in remote rural areas and their retail customers have little other choice than to buy from these abattoirs. However, the study identified poor knowledge on the costs and benefits of a traceability system as a potential drawback in doing a proper cost benefit analysis and therefore proper research on the economics of traceability systems was almost impossible. At the abattoir level, traceability systems are quite easily implemented because it is much easier to trace a single carcass in an abattoir than to trace different pieces of one carcass in the processing plant. Since this study did not include detail pertaining to the downstream tiers; meat processors, packers, wholesalers and retailers, it is not possible to conclude that the entire sheep supply chain can guarantee a product’s origin in the case of Karoo Lamb. The integrity of these role players will play a vital role in their ability to guarantee the origin of a sheep meat product especially when sheep carcasses are moved outside the Karoo boundaries for processing and packaging. It is therefore clear that the downstream tiers play a vital part in the South African sheep meat industry in terms of chain-wide traceability and transparency in order to guarantee the origin of a sheep meat product such as Karoo Lamb. Further research is therefore required to evaluate the other role players in the sheep meat industry for chain-wide traceabiltiy systems, in order to test the readiness of this chain and industry to guarantee the origin of a product like Karoo Lamb. / Dissertation (MSc(Agric))--University of Pretoria, 2013. / Agricultural Economics, Extension and Rural Development / unrestricted
17

Avaliação da técnica de coloração AgNOR em células saudáveis de testículo de ovinos / Evaluation of AgNOR staining method in healthy cells of ovine testicle

Ibrahim, Daniel Boabaid 13 April 2012 (has links)
Made available in DSpace on 2016-01-26T18:55:35Z (GMT). No. of bitstreams: 1 daniel.pdf: 186929 bytes, checksum: 3b546022c9b10042ce06a35c124600cd (MD5) Previous issue date: 2012-04-13 / The silver staining technique for AgNOR nucleolar organizer regions (NORs) is characterized by marking proteins linked to the ribosomal ribonucleic acid, evaluating cell proliferation. The aim was to study the validity of the AgNOR staining technique in the testicular cell proliferation in crossbred ovine. Was used treis pairs forty crossbred sheep testes between six and ten months old.Wilcoxon and Spearman tests were used with a significance level of 5%. The mean NORs count in cells of the gonads right and left were respectively: spermatogonia (8.77±1.14 and 9.04±0.96), spermatocyte (4.99±2.00 and 6.20±2.07, P<0.05), Leydig (8.05±2.82 and 7.89±2.29) and Sertoli cells (8.07±1.88 and 7.61±2.16; P<0.05). There was a correlation between the mean values for right and left sides for the number of NORs (P<0.05) between Leydig x spermatocytes (0.49); spermatocytes x Sertoli (0.49) and Sertoli x Leydig (0.96). The study demonstrates that the AgNOR staining technique is indicated to evaluate the cell proliferative potential in ovine testis with practical implementation and low cost. / A coloração pela prata das regiões organizadoras de nucléolos (NORs) é caracterizada por marcar proteínas ligadas ao ácido ribonucléico ribossômico, avaliando a proliferação em células normais ou neoplásicas. O objetivo do trabalho foi estudar em testículos de ovinos obtidos em matadouro a validade do uso da técnica de coloração AgNOR na proliferação de células saudáveis da linhagem espermatogênica. Utilizou-se 43 pares de testículos de ovinos mestiços entre seis e 10 meses de idade. Testes de Wilcoxon e Spearman foram empregados, com nível de 5%. As médias das NORs nas células das gônadas direita e esquerda foram respectivamente: espermatogônia (8,77±1,14 e 9,04±0,96), espermatócito (4,99±2,00 e 6,20±2,07; P<0,05), Leydig (8,05±2,82 e 7,89±2,29) e Sertoli (8,07±1,88 e 7,61±2,16; P<0,05). Houve correlação (P<0,05) entre os lados para o número de NORs: espermatócito x Leydig (0,49); espermatócito x Sertoli (0,49) e Leydig x Sertoli (0,96). Conclui-se ser válido o emprego da técnica AgNOR para avaliar o potencial proliferativo das células saudáveis em testículos de ovinos com prática execução e baixo custo.
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Avaliação da técnica de coloração AgNOR em células saudáveis de testículo de ovinos / Evaluation of AgNOR staining method in healthy cells of ovine testicle

Ibrahim, Daniel Boabaid 13 April 2012 (has links)
Made available in DSpace on 2016-07-18T17:53:10Z (GMT). No. of bitstreams: 1 daniel.pdf: 186929 bytes, checksum: 3b546022c9b10042ce06a35c124600cd (MD5) Previous issue date: 2012-04-13 / The silver staining technique for AgNOR nucleolar organizer regions (NORs) is characterized by marking proteins linked to the ribosomal ribonucleic acid, evaluating cell proliferation. The aim was to study the validity of the AgNOR staining technique in the testicular cell proliferation in crossbred ovine. Was used treis pairs forty crossbred sheep testes between six and ten months old.Wilcoxon and Spearman tests were used with a significance level of 5%. The mean NORs count in cells of the gonads right and left were respectively: spermatogonia (8.77±1.14 and 9.04±0.96), spermatocyte (4.99±2.00 and 6.20±2.07, P<0.05), Leydig (8.05±2.82 and 7.89±2.29) and Sertoli cells (8.07±1.88 and 7.61±2.16; P<0.05). There was a correlation between the mean values for right and left sides for the number of NORs (P<0.05) between Leydig x spermatocytes (0.49); spermatocytes x Sertoli (0.49) and Sertoli x Leydig (0.96). The study demonstrates that the AgNOR staining technique is indicated to evaluate the cell proliferative potential in ovine testis with practical implementation and low cost. / A coloração pela prata das regiões organizadoras de nucléolos (NORs) é caracterizada por marcar proteínas ligadas ao ácido ribonucléico ribossômico, avaliando a proliferação em células normais ou neoplásicas. O objetivo do trabalho foi estudar em testículos de ovinos obtidos em matadouro a validade do uso da técnica de coloração AgNOR na proliferação de células saudáveis da linhagem espermatogênica. Utilizou-se 43 pares de testículos de ovinos mestiços entre seis e 10 meses de idade. Testes de Wilcoxon e Spearman foram empregados, com nível de 5%. As médias das NORs nas células das gônadas direita e esquerda foram respectivamente: espermatogônia (8,77±1,14 e 9,04±0,96), espermatócito (4,99±2,00 e 6,20±2,07; P<0,05), Leydig (8,05±2,82 e 7,89±2,29) e Sertoli (8,07±1,88 e 7,61±2,16; P<0,05). Houve correlação (P<0,05) entre os lados para o número de NORs: espermatócito x Leydig (0,49); espermatócito x Sertoli (0,49) e Leydig x Sertoli (0,96). Conclui-se ser válido o emprego da técnica AgNOR para avaliar o potencial proliferativo das células saudáveis em testículos de ovinos com prática execução e baixo custo.
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Participatory risk assessment for harvesting of impala (Aepyceros melampus) and the distribution of by-products

Ramrajh, Shashikala 16 July 2013 (has links)
The demand for the control of safe food, from consumers the world over, has revolutionized the manner in which wild game meat harvesting occurs. In developed countries, food quality, food and human safety with quality controlling systems embracing environmental carbon footprint issues are constantly improving, for international harmonization at each level of production “from stable to table”, “farm to fork”, “field to yield” as well as from “cradle to grave”. Food industries globally have adopted the in Hazard Analysis Critical control Point (HACCP) system. This is a risk assessment process using Hygiene Assessment Systems (HAS) as a mitigating strategy for risk communication through training. It is also a holistic system that is compatible with international trends designed not only for food safety and quality, but it also embraces other aspects of farming such as animal welfare, environmental management and Occupational Safety and Health. Global marketing for international trade demands quality assurance from trading partners thereby promoting economic growth for developing countries. The watch dog bodies such as the World Trade Organisation (WTO) prohibit trading for non-compliance, therefore trade barriers are in place for uncertified food of animal origin, EU regulations are stringent requirements that need compliance and so too the OIE regulations for disease control, while the Codex Alimentarius Commission maintains trade harmonization. In South Africa Hygiene Assessment Systems (HAS) is a National Hygiene management strategy implemented at abattoirs, that promotes and facilitates quality and hygiene and is reflective of South African quality abroad. It is prescribed under the section, “Essential National Standards” in the Meat Safety Act, 2000, (Act 40 of 2000). This Act covers red meat and includes both domestic animals and game. The Veterinary Procedural Notices (VPN’s) are used for export of game and give far more detailed guidelines than the legislation for game meat sold and consumed locally in South Africa. The objective of the Hygiene Assessment System (HAS) is to create a national awareness of quality to better improve the quality of life of all South Africans, whilst at the same time it is used as an auditing tool for Veterinary Public Health to effectively compare essential standards within the nine provinces. Currently this programme is referred to as the National Abattoir Rating Scheme (NARS), which is only applicable to the high and low throughput Red Meat and Poultry abattoirs in South Africa and not to the Game or Rural abattoirs, thereby further compounding the duality of food standards with food safety being compromised. This study has been undertaken because there are inadequate risk control measures such as introduction of Hazard Analysis Critical Control Point (HACCP) guidelines on primary and secondary meat inspection, specifically on game for local consumption, not only within South Africa, but in the international arena as well. A revision of the HAS document and audit will also be needed to meet with the local (not just export) criteria for wild game harvesting, to enable food safety, thus enabling food security in the remote non - agricultural areas in KwaZulu -Natal. Venison is the meat of today because of health priorities that have arisen over the last ten years. It is low in trans - fatty acids and is regarded internationally as a healthy product produced organically in a free range situation. South Africa has a large potential export market for venison to the European Union because the demand, for venison, exceeds supply in Europe. However, the European Union’s “safe food regulation” that was introduced between 2005 and 2007 with an implementation date of 2008 (Regulation1021/2008) has made it imperative that the HACCP principle is applied to any food or food product of animal origin imported into the European Union or its member states. Also, HACCP specifies that a multidisciplinary team of experts is selected. This then lends itself to a participatory approach to risk assessment as wide consultation is required. This participatory approach was used, including expert opinion surveys and focus group discussions with stakeholders and role-players in the game industry such as commercial hunters, state veterinary services and game ranch owners. Such participants may have better insight into existing conditions than external experts with recognised educational qualifications, usually used in the HACCP team. From this and the relevant Veterinary Procedural Notices for game harvesting, a HACCP process flow and critical control points were derived for the primary phase of meat inspection, including slaughter, primary meat inspection and loading for transport to the abattoir. This was modified during a phase or trial harvesting and then implemented during the harvest of 1758 impala carcasses which were subsequently exported. In addition, environmental risks were considered and a risk mitigation strategy designed, to reduce any possible environmental impacts. In northern Kwazulu Natal, game ranches and conservation areas are in close proximity to the rural poor where food is scarce and comes at a premium price. These game farms harvest seasonally for either the local or export market, hence there is abundance of game offal and by-products available, yet it is at present left in the field or taken to the vulture restaurants (in line with the VPN). Participatory risk analysis was thus also used to investigate the feasibility of using edible offal from impala (Aepyceros melampus) as a source of renewable protein, to address food security issues in impoverished communities in the study area, the districts of uPongola and Jozini, in northern KwaZulu Natal. Structured interviews on the cultural acceptability of impala offal were held with 162 randomly sampled adult respondents in veterinary districts associated with dip tanks. A two stage cluster design was used where the state veterinary areas were stage one and the dip tanks (with proportional random sampling of community members) were the second stage. Offal is a popular food in South Africa in different cultures, called “ithumbu” in IsiZulu, “ boti” by the Indian group, “afval” in Afrikaans and “tripe” in English. Generally demand outstrips supply of offal at red meat abattoirs in South Africa. It was found that there was no significant difference between those who would eat impala offal and those who would eat the offal of sheep. It was concluded that it is feasible to use inspected game offal from impala as a protein source in much the same way as red meat offal is used and that the current practice of leaving the offal for predators was likely, if it continues, to cause imbalances in the predator/ prey ratio on game farms. It is recommended that the VPN for game be amended to encompass inspected offal being allowed into the formal food chain, in line with the standard operating procedure developed during this study. Also that current fragmentation of legislation and the implementation thereof is revisited for effective control for harmonisation of food safety standards for game meat within South Africa. / Dissertation (MMedVet)--University of Pretoria, 2012. / Paraclinical Sciences / unrestricted
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O rigor da morte : a construção simbolica do animal de açougue na produção industrial brasileira / The rigor of death : the symbolic construction of the meat animal in the brazilian production

Dias, Juliana Vergueiro Gomes 12 August 2018 (has links)
Orientador: Nadia Farage / Dissertação (mestrado) - Universidade Estadual de Campina, Instituto de Filosofia e Ciencias Humanas / Made available in DSpace on 2018-08-12T20:10:28Z (GMT). No. of bitstreams: 1 Dias_JulianaVergueiroGomes_M.pdf: 2308832 bytes, checksum: a3bbdd20b7f8d298a75860d5de061891 (MD5) Previous issue date: 2009 / Resumo: A presente dissertação faz uma análise da construção do estatuto simbólico dos animais domésticos comestíveis no contexto industrial brasileiro contemporâneo. Toma como foco a produção animal, e, mais especificamente, sua fase final, o abate, que, articulando-se ao universo do consumo, constitui um forte momento simbólico na construção do comestível, isto é, a categoria histórica "animal de açougue". A indústria da carne pressupõe disjunções e afastamentos, que têm como resultado a produção de uma mercadoria, autônoma e distante de sua verdadeira origem, o animal. Dentre os mecanismos de afastamento promovidos pela indústria, o método do abate humanitário apresenta alto rendimento simbólico, pois permite a conjunção paradoxal entre a mitigação do sofrimento animal e a eficiência, súmula da lógica do capital industrial / Abstract: This work analyses the construction of the symbolic statute of the edible domestic animals in the contemporary brazilian industrial context. The focal point is on animal production and more specifically in its final phase, the slaughtering, which, in articulation with the universe of consumption, constitutes an important moment in the construction of the edible, i.e., the historical category of "meat animal". The meat industry presupposes disjunctions and distances, which result in the production of a commodity, autonomous and distant from its actual origin, the animal. Amongst the disjunction mechanisms promoted by the industry, the method of humane slaughter yields high symbolic results, since it permits the paradoxical gathering of the mitigation of animal suffering and the efficiency, epitome of the logic of the industrial capital / Mestrado / Mestre em Antropologia Social

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