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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.
41

Efeito da fototerapia com doidos superluminosos (890nm) na reparação tendínea: modelo experimental em ovinos. -

Mattos, Luiz Henrique Lima de [UNESP] 11 December 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-12-11Bitstream added on 2014-06-13T20:50:47Z : No. of bitstreams: 1 mattos_lhl_me_botfmvz.pdf: 829995 bytes, checksum: 73939ace7310759bbb3cd6221db93211 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este projeto teve como objetivo avaliar os efeitos da fototerapia na cicatrização do tendão usando diodos superluminosos fixados em 890nm. Foram induzidas lesões cirúrgicas de 0,2cm de largura x 0,5cm de comprimento, realizadas no segundo terço do Tendão Flexor Digital Superficial de 10 ovelhas saudáveis que foram divididos em dois grupos: grupo tratado com diodos superluminosos com o comprimento de onda acima mencionado e grupo controle, tratado com placebo. A Cinesioterapia foi realizada em ambos os grupos. Os exames ultrassonográficos Modo B e Doppler foram realizados durante os primeiros 14 dias após a cirurgia e, em seguida, nos dias 21 e 28, a fim de avaliar o processo de cicatrização do tendão. A biópsia foi realizada no dia 28 para avaliar a neovascularização e o padrão tendão de fibra no exame histopatológico. Ausência de claudicação e uma melhoria significativa (p < 0,05) na dor após palpação foram observadas no grupo tratado. Além disso, no modo B foi evidenciada uma redução significativa do edema (p < 0,05) nestes animais. Não foi encontrada diferença estatística em relação à evolução da lesão. Houve diferença histológica (p < 0,05) para a neovascularização no grupo tratado. Fototerapia com diodos superluminosos de 890nm minimiza os efeitos do processo inflamatório / This project aimed to evaluate the effects of phototherapy on tendon healing using superluminous diodes set at 890nm. Surgical lesions were induced by 0.2 cm wide x 0.5 cm long, made in the second third of the superficial digital flexor tendon of 10 healthy sheep were divided into two groups: group treated with superluminous diodes with the wavelength mentioned above and control group treated with placebo. The Kinesiotherapy was performed in both groups. The B mode ultrasound examination and Doppler were performed during the first 14 days after surgery and then on days 21 and 28, to evaluate the healing of the tendon. A biopsy was performed on day 28 to evaluate neovascularization and tendon fiber pattern on histopathological examination. No lameness and a significant improvement (p <0.05) in pain after palpation were observed in the treated group. Furthermore, in the mode B was observed a significant reduction in edema (p <0.05) in these animals. No statistical difference was found in relation to the evolution of the lesion. Significant difference was seen (p <0.05) for neovascularization in the treated group. Phototherapy with 890nm superluminous diodes minimizes the effects of the inflammatory process
42

Estudo clínico-citológico em ovinos sadios e portadores de afecções pulmonares de ocorrência natural, utilizando-se o lavado traqueobrônquico como auxílio diagnóstico

Marcondes, Julio Simões [UNESP] 22 February 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-22Bitstream added on 2014-06-13T19:30:12Z : No. of bitstreams: 1 marcondes_js_me_botfmvz.pdf: 567670 bytes, checksum: 1ff58f582a8a4a863c4ee08a32172d9a (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os estudos das secreções traqueobrônquicas são amplamente utilizados nas pesquisas de condições patológicas pulmonares nas diversas espécies animais, inclusive no homem. Os objetivos desta pesquisa foram a viabilização da técnica de colheita de lavado traqueobrônquico na espécie ovina e o estudo da relação clínico-citológica do lavado de ovinos portadores de afecções respiratórias e clinicamente sadios. Foram utilizados neste estudo 19 ovinos sem sintomatologia respiratória e 23 portadores de enfermidade respiratória com sinais clínicos e envolvimento de vias aéreas, divididos nos respectivos grupos. Após o exame físico foi realizado o lavado traqueobrônquico por via nasotraqueal. A colheita do lavado foi feita com a inoculação e aspiração de solução fisiológica estéril. As amostras foram processadas citologicamente através de citocentrifugação e coradas pelos métodos Giemsa, Shorr e Gram. Nos animais sadios notou-se predomínio de macrófagos, seguido por células epiteliais cilíndricas, neutrófilos e linfócitos. No grupo de animais doentes notou-se redução no número de macrófagos e aumento da freqüência cardíaca. Embora não tenha ocorrido diferença estatística significativa entre os grupos avaliados, notou-se tendência ao aumento de neutrófilos nos animais doentes. A técnica estudada mostrou-se eficaz na obtenção de fluidos traqueobrônquicos, por ser de fácil realização por médicos veterinários no campo, pouco dispendiosa, e obter material representativo da região traqueobrônquica. / The studies of the tracheobrochial secretions are very useful in the research of the lung pathological conditions in different animal's species and in humans. The purposes of this research are to enable the collection technique of the tracheobronchial lavage in ovine and the study of the clinical cytology relationship of the lavage in ovines with respiratory disease and clinically healthy. In this study there were used 19 ovines without respiratory symptoms and 23 with respiratory disease with symptoms and airway involvement, separated in respective groups. After physical examination the tracheobronchial lavage was performed by nasotracheal via. The tracheobronchial lavage was performed by injection and aspiration of sterile saline. Cytology of the samples was proceeding by centrifugation and collored by Giemsa, Shorr and Gram methods. In the healthy animals was noted prevalence of macrophages, followed by cylindric epithelial cells, neutrophils and lymphocytes. In the ill animals group there was reduction in the macrophages and higher heart rate. Despite there was no considerable statistic difference between the analyzed groups, a tendency in the increase of the neutrophils number in the ill group was noted. The evaluated technical showed itself to be efficient to obtain tracheobronchial fluid, considering its easy proceeding by veterinarians in the field, no expensive and obtaining representative volume of the samples from the tracheobronchial region.
43

Efeito da fototerapia com doidos superluminosos (890nm) na reparação tendínea : modelo experimental em ovinos. -

Mattos, Luiz Henrique Lima de. January 2012 (has links)
Orientador: Ana Liz Garcia Alves / Coorientador: Roberto Calderon Gonçalves / Banca: Monica de Oliveira Orsi Gameiro / Banca: Celso Antonio Rodrigues / Resumo: Este projeto teve como objetivo avaliar os efeitos da fototerapia na cicatrização do tendão usando diodos superluminosos fixados em 890nm. Foram induzidas lesões cirúrgicas de 0,2cm de largura x 0,5cm de comprimento, realizadas no segundo terço do Tendão Flexor Digital Superficial de 10 ovelhas saudáveis que foram divididos em dois grupos: grupo tratado com diodos superluminosos com o comprimento de onda acima mencionado e grupo controle, tratado com placebo. A Cinesioterapia foi realizada em ambos os grupos. Os exames ultrassonográficos Modo B e Doppler foram realizados durante os primeiros 14 dias após a cirurgia e, em seguida, nos dias 21 e 28, a fim de avaliar o processo de cicatrização do tendão. A biópsia foi realizada no dia 28 para avaliar a neovascularização e o padrão tendão de fibra no exame histopatológico. Ausência de claudicação e uma melhoria significativa (p < 0,05) na dor após palpação foram observadas no grupo tratado. Além disso, no modo B foi evidenciada uma redução significativa do edema (p < 0,05) nestes animais. Não foi encontrada diferença estatística em relação à evolução da lesão. Houve diferença histológica (p < 0,05) para a neovascularização no grupo tratado. Fototerapia com diodos superluminosos de 890nm minimiza os efeitos do processo inflamatório / Abstract: This project aimed to evaluate the effects of phototherapy on tendon healing using superluminous diodes set at 890nm. Surgical lesions were induced by 0.2 cm wide x 0.5 cm long, made in the second third of the superficial digital flexor tendon of 10 healthy sheep were divided into two groups: group treated with superluminous diodes with the wavelength mentioned above and control group treated with placebo. The Kinesiotherapy was performed in both groups. The B mode ultrasound examination and Doppler were performed during the first 14 days after surgery and then on days 21 and 28, to evaluate the healing of the tendon. A biopsy was performed on day 28 to evaluate neovascularization and tendon fiber pattern on histopathological examination. No lameness and a significant improvement (p <0.05) in pain after palpation were observed in the treated group. Furthermore, in the mode B was observed a significant reduction in edema (p <0.05) in these animals. No statistical difference was found in relation to the evolution of the lesion. Significant difference was seen (p <0.05) for neovascularization in the treated group. Phototherapy with 890nm superluminous diodes minimizes the effects of the inflammatory process / Mestre
44

Biological control of gastrointestinal nematodes of small ruminants, using Bacillus thuringiensis (Berliner) and Clonostachys rosea (Schroers).

Baloyi, Mahlatse Annabella. January 2011 (has links)
Gastrointestinal nematode parasites cause great losses in the production of small ruminants through reduced productivity and the cost of preventive and curative treatments. Because of the threat of anthelmintic resistance, biological control of sheep nematodes has been identified as an alternative to anthelmintic drugs. Bacillus thuringiensis (Bt) (Berliner) and Clonostachys rosea (Schroers) have been widely studied as biocontrol agents. B. thuringiensis has been used for the biocontrol of insects and C. rosea has been successfully used as biocontrol agent of Botrytis cinera (De Bary) in plants. B. thuringiensis and C. rosea strains were isolated from soil collected from the Livestock Section at Ukulinga Research Farm, University of KwaZulu Natal, Pietermaritzburg. Twenty-five strains of Bt and 10 strains of C. rosea were successfully isolated. The Bt colonies were identified by their circular, white, flat and undulate character, and the gram-positive and rod-shaped endospores. C. rosea was identified by white colonies on Potato-dextose agar and the characteristic conidiophores, which were branched and showed phialides at the tips. In vitro screening of the isolates was undertaken to select the best isolates. The isolates that caused significantly greater mortality were Bt isolate B2, B10 and B12 and C. rosea isolates P1, P3 and P8. These isolates caused substantial nematode mortality in both faeces and water bioassay. Nematode counts were reduced by 28.5% to 62% and 44% to 69.9% in faecal bioassay for Bt and C. rosea, respectively. In the water bioassay, nematode counts were reduced by 62% to 85% for Bt and by 62.7% to 89.3% for C. rosea. The best inoculum level at which the best isolates were most effective, and the optimum frequency of application were determined. The trial was conducted using bioassays with faeces and water. Inoculum levels of 10(6), 10(8), 10(10), 10(12) spores ml-1 for Bt and 10(6), 10(8) and 10(10) conidia ml-1 for C. rosea was used in the faecal bioassay. The inoculum levels tested in water bioassay were 10(6), 10(8), 10(10) and 10(12) spores ml-1 for Bt and 10(9), 10(10), 10(11), 10(12) conidia ml-1 for C. rosea. In the faecal bioassay, B2 was the most effective Bt isolate at an inoculum level of 10(10) spores ml-1. Isolate P3 was the best C. rosea isolate at 10(8) conidia ml-1. In the water bioassay, Isolate P3 caused a mortality of 85% at inoculum levels of 10(9), 10(10) and 10(11) conidia ml-1. The performance of biological control agents in the field is sometimes inconsistent. Combining different biocontrol agents may be a method of improving their reliability and performance. However, the combination of most of the isolates was antagonistic, with efficacy less than that of either individual biocontrol agent. In particular, Isolate P3 was more effective when used alone than when combined with any other isolates. Therefore, the combination of biocontrol agents does not always result in synergistic interaction. There were some additive interactions between two bacterial isolates, and with one bacterial and fungal combination. The effect of feeding the best of the biocontrol agents, or diatomaceous earth (DE), was evaluated in sheep. Two doses of Bt (1g and 2g kg-1BW) and C. rosea (1g kg-1BW) reduced the numbers of L3 nematode larvae in sheep faeces. The DE product (at 15% of feed) also reduced L3 numbers but it was less effective than either the Bt or the C. rosea products. Nematode counts were reduced by 74.6%, 75.1%, 84.6%, 68.5% and 27.5% for Bt 1g kg-1BW, Bt 2g kg-1BW, C. rosea (1g kg-1 BW), DE and control, respectively. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
45

Pneumonia and pleurisy in sheep : studies of prevalence, risk factors, vaccine efficacy and economic impact : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Palmerston North, New Zealand

Goodwin-Ray, Kathryn Anne January 2006 (has links)
The objectives of this thesis were to investigate patterns of lamb pneumonia prevalence of a large sample of New Zealand flocks including an investigation of spatial patterns, to evaluate farm-level risk factors for lamb pneumonia, to determine the efficacy of a commercially available vaccine for the disease and to estimate the likely cost of lamb pneumonia and pleurisy for New Zealand sheep farmers. Data were collected by ASURE NZ Ltd. meat inspectors at processing plants in Canterbury, Manawatu and Gisborne between December 2000 and September 2001. All lambs processed at these plants were scored for pneumonia (scores: 0, <10% or ≥10% lung surface area affected) involving 1,899,556 lambs from 1,719 farms. Pneumonia prevalence was evaluated for spatial patterns at farm level and for hierarchical patterns at lamb, mob and farm levels (Chapter 3). The average pneumonia prevalence in Canterbury, Feilding and Gisborne was 34.2%, 19.1% and 21.4% respectively. Odds ratios of lambs slaughtered between March and May were vastly higher than those slaughtered in other months indicating longer growth periods due to pneumonia. Since pneumonia scores were more variable between mobs within a flock than between flocks, it was concluded that pneumonia scores were poor indicators for the flock pneumonia level due to their lack of repeatability. There was no statistically significant spatial autocorrelation in pneumonia prevalence for any region, hence lamb pneumonia appeared to be largely independent of topographical and geo-climatic factors. A questionnaire-based case-control study was conducted investigating farm-level factors from a sample of farms with either high (case) or zero (control) pneumonia prevalence at slaughter (Chapter 4). Significant risk factors for case farms were: (1) shearing lambs on the day of weaning, (2) breeding ewe replacements on-farm (3) number of lambs sold (an indicator of flock size) and (4) increased percentage of lambs sold late in the season (March to May). Significant protective factors included: (1) set stocking lambs after weaning, (2) injecting lambs with Vitamin B12 at the time of tailing, (3) injecting lambs with Vitamin B12 at weaning. In Canterbury, flocks with Romney ewes and other ewes had a higher risk of pneumonia than those with fine wool type ewes (Merinos, Corriedales or Halfbreds). In a clinical trial, 8,364 lambs from seven commercial sheep farms with a history of lamb pneumonia were vaccinated with Ovipast Plus® or placebo by systematic random allocation within mob and farm. An assessment of the extent of pneumonic lesions was conducted at slaughter and lamb growth rate was monitored through the growth period (Chapter 5). The vaccination trial showed no statistically significant effect of Ovipast® vaccination on the extent of lung lesions at slaughter or ADG of lambs from the first treatment until slaughter. No significant differences were found between isolation rates of Pasteurella spp and patho-histological classifications from pneumonic lung samples of placebo and vaccinated lambs. A spreadsheet-based stochastic model was constructed to estimate the cost of lamb pneumonia and pleurisy to New Zealand farmers. The estimate was based on data of the effect of pneumonia on lamb growth rate, distributions of pneumonia severity, prevalence of moderate to severe pneumonia (≥10% lung surface area) and pleurisy prevalence (Chapter 6). The simulated annual average cost of pneumonia was NZ $28.1 million and that of pleurisy NZ $25.1 million. The combined cost of pneumonia and pleurisy to New Zealand farmers had an average of NZ $53.2 million (95% stochastic interval = $32.4-$78.9 million), or US $31.9 million per annum. This would equate to NZ $2.32 per lamb. In comparison, animal health, shearing expenses and feed expenses cost NZ $2.37, $2.62 and $1.85 per lamb, respectively. This research has demonstrated sub-clinical pneumonia to be a widespread disease in the New Zealand sheep farming population while previous research has focussed on case studies of affected farms. The estimated costs of pneumonia and pleurisy to New Zealand farmers ($53.2 million) highlight the financial effects of these diseases and the need for further research. We also found that the commercially available vaccine could neither prevent sub-clinical effects (lamb growth rate) nor clinical manifestations (pneumonic lung lesions) of lamb pneumonia. The case-control study has revealed farm-level factors which, in the absence of effective vaccines, indicated management practices that farmers might perceive as opportunities to control lamb pneumonia. However, it is advisable to evaluate the efficiency of such management changes. Pneumonia is aetiologically complex disease involving the interplay of many environmental, host and pathogen factors. It is also a difficult disease to study in the absence of diagnostic tests in live animals. However, further research should focus on the development of management changes until effective vaccines are available. A starting point for this research would be to evaluate the impact of such management changes in reducing the incidence of lamb pneumonia. More specifically, the roles of stress during crowding of lambs for extended periods warrants further investigation. The development of efficient vaccines requires an analysis of pathogens, especially Pasteurella (Mannheimia) haemolytica and Mycoplasma species, the sources of infection, their strain diversity and transmission dynamics.
46

The space-time distribution of Palearctic Culicoides spp. vectors of Bluetongue disease in Europe / Distribution spatio-temporelle du genre Culicoides, vecteur de la fièvre catarrhale ovine

Rigot, Thibaud 24 October 2011 (has links)
Abstract :Bluetongue (BT) is a vector-borne infectious disease primarily transmitted to even- toed ungulates by the bite of several Culicoides species. The global distribution of BT can be attributed to the ubiquity of its vectors and its rapid spread, likely to the enhancement of human activities (intensification of animal production, trans- port, changing habitat). During the last decades, BT established in Southern Europe and more recently emerged in Northern Europe, causing the death of millions of domestic ruminants. On the same time, a Belgian research project has been set up to develop remote-sensing tools to study the EPidemiology and Space-TIme dynamicS of infectious diseases (EPISTIS). In that general framework, this thesis aimed to study the space-time distribution of the main Culicoides vectors occurring in Italy and Belgium, at two different scales. Firstly, we aimed to clarify the role of several eco-climatic factors on the regional-scale distribution of C. imicola in time, based on weekly samplings achieved throughout Italy from 2001 to 2006 and to develop an easy-to-use and reproducible tool, which could be widely validated on the basis of former vector sampling and freely accessible remote-sensing data. Secondly, we aimed to investigate how Culicoides species were distributed in the fine-scale habitat encountered throughout the agro-ecological landscapes of Belgium, while recent studies have suggested that the landscapes configuration could explain the spatial distribution of BT. In the first part, we showed that an autoregressive model where the observed monthly growth rate is predicted by monthly temperature, allowed predicting >70% of the seasonal variability in C. imicola trap catches. The model predicted the seasonality, the altitudinal gradient, and the low populations’ activity taking place during the winter. Incorporating eco-climatic indices such as the Normalized Difference Vegetation Index into the model did not enhance its predictive power. In the second part, we quantified how Culicoides populations are spatially structured in the neighbourhood of farms, and demonstrated the unexpectedly high level of population found in forest. We also showed how four classes of land use could influence the relative abundances of Culicoides species in the agro-ecological landscapes of Belgium. Although in summer, BT vectors were abundant in each of the four classes investigated, their relative abundances varied strongly as a function of sex, species and environmental conditions, and we quantified these variations. Finally, we also presented a new method to quantify the interference between Onderstepoort light traps, and used it to measure their range of attraction for several of the most common BT vectors species in Northern Europe. The model developed on C. imicola in Italy provided enthusiastic perspectives regarding the regional-scale analyses of its distribution in time, although further improvements are nevertheless required in order to assess the broad scale ecology of BT vectors throughout Europe. Mapping the abundances of C. imicola in Sardinia high- lighted an important lack of reliability attributable to the many land use classes that are currently not sampled in the vector surveillance achieved across Europe. Together with the novelties presented in the second part and the recent findings establishing that BT could circulate among wild hosts in both epidemiological systems (i.e. in Southern and Northern Europe), we call for increasing epidemiological and entomo- logical studies at the interface between farms and the surrounding natural habitats. Last, depicting in time the landscape-scale findings for Northern Europe highlighted how dramatic could be the role played by intensive farming practices to maintain BT within the agro-ecological landscapes studied and to facilitate its circulation between them. Quantifying the amplitude of the risk of disease transmission linked to these practices would require a further complex modeling approach accounting simultaneously for the diel activity of hosts, mainly resulting from the farming activities, the diel activities of different vector species and the landscapes configuration found in contrasted agro-ecological systems.<p>Résumé :La fièvre catarrhale ovine (FCO), encore appelée maladie de la langue bleue, est une maladie infectieuse des ruminants transmise par la piqûre d’un vecteur de type moucheron appartenant au genre Culicoides (Diptera :Ceratopogonidae). L’ubiquité de ses vecteurs peut expliquer son succès d’installation à l’échelle globale. Par ailleurs, sa rapide expansion a été grandement facilitée par l’importante activité anthropique (élevage, transport, modification de l’habitat) et peut-être même par les changements climatiques globaux. La FCO a été récemment qualifiée de maladie infectieuse émergente en Europe du fait de (i) son récent établissement dans la région, bien au delà de son aire de répartition traditionnelle, (ii) de sa forte capacité de dispersion affectant chaque jour un nombre plus important d’hôtes et enfin (iii) de sa forte virulence. Après avoir détaillé les caractéristiques majeures des deux principaux foyers de FCO rencontrés en Europe depuis 1998, la présente thèse s’est plus particulièrement intéressée à l’étude de la distribution spatio-temporelle de ses principaux vecteurs dans le sud (partie 1) puis dans le nord (partie 2) de l’Europe, à différentes échelles. Dans la première partie, un modèle discret, spatialement et temporellement explicite, a été développé afin de mesurer l’influence de différents facteurs éco-climatiques sur la distribution de Culicoides imicola, principal vecteur de la FCO dans le Bassin Méditerranéen. Les profils mensuels de distribution rencontrés en Sardaigne durant 6 années consécutives ont ainsi pu être reconstitués, principalement sur base de la température. Une cartographie de l’abondance de C. imicola sur le territoire a permis de mettre à jour le manque d’information sur sa distribution en dehors des exploitations agricoles. Dans la deuxième partie du travail, nous nous sommes penchés sur la distribution spatiale des Culicoides tels qu’on peut les rencontrer au sein de différents paysages agro-écologiques de Belgique. Nous avons ainsi pu décrire la structure adoptée par les populations de Culicoides au voisinage des fermes ainsi que quantifier l’importante population présente dans les forêts avoisinantes. Nous avons par ailleurs montré l’influence de différentes catégories d’utilisation du sol sur l’abondance et la composition en espèces. Enfin, nous avons présenté une méthode permettant de quantifier l’interférence entre des pièges lumineux utilisés dans un même paysage pour échantillonner les populations, et l’avons utilisé afin de mesurer leur rayon d’attractivité sur les espèces vectrices les plus communément rencontrées dans le nord de l’Europe. En guise de conclusion générale et conjointement aux récentes découvertes de cas de FCO au sein de la faune sauvage européenne, nous appelons à réaliser un plus grand nombre d’études éco-épidémiologiques à l’interface entre exploitations agricoles et zones (semi-) naturelles avoisinantes. En outres, les résultats présentés dans la seconde partie ont été mis en relation avec le mode de fonctionnement journalier de nos exploitations agricoles. Nous avons ainsi pu déduire le rôle dramatique joué par les pratiques agricoles intensives dans le maintien du virus de la FCO au sein de nos paysages agro-écologiques, ainsi que dans sa circulation d’un paysage à l’autre. Un cadre de modélisation complexe permettant une analyse simultanée de l’activité nycthémérale des hôtes de la FCO et de ses vecteurs Culicoides en fonction de la configuration des paysages agro-écologiques est néanmoins requis afin de quantifier l’amplitude du risque de transmission de la FCO lié aux pratiques agricoles intensives. / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
47

Sheep production practices, flock dynamics, body condition and weight variation in two ecologically different resource-poor communal farming systems

Mapiliyao, Luke January 2010 (has links)
The objective of this study was to determine sheep production practices, constraints, flock dynamics, body condition and weight variation in two ecologically different resource-poor communal farming systems of the Eastern Cape Province of South Africa. Mean sheep flock sizes per household were not significantly different between the two ecologically different areas (villages); Gaga (19.0±3.10) and Sompondo (18.3±3.10). Shortage of feed, disease and parasite were reported the most important constraints across the two villages. In both villages, sheep housing was poorly constructed using acacia brushwoods. Fewer farmers owned rams: the rams to ewes ratio for the two villages were 1:20, 1:19 for Gaga and Sompondo, respectively. The low ram: ewe ratios reported suggest that inbreeding might have been reducing productivity of their flocks. There was also uncontrolled breeding due to undefined and mating seasons. Gall sickness, heart water and footrot caused most of the sheep mortalities. Dohne Merinos were the common genotypes in the two villages. Total entrances for each flock were higher (p < 0.05) in hot-dry season and hot-wet season than in other seasons. Most of the entrances were lambs and were born in hot-dry season (September) and cool-dry season (June) for larger flocks (10.90 ± 3.02) and for small flocks (3.65 ± 3.02). High lamb mortalities were experienced in the post-rainy (April) and hot-wet (December) season. There was a significant interaction between season and flock size. Most of the sales occurred in the hot-wet season. Ecological area had significant effect on sheep production potential (p < 0.05) in both flock classes. The average sheep production efficiency (SPE) value for Gaga and Sompondo were 0.50 ± 0.116 and 0.50 ± 0.096 respectively. The SPE for large flock was higher (p < 0.05) by season and flock size. Large flocks had a higher (p < 0.05) SPE values and the SPE ranged from 1.11 ± 0.193 in April, a post-rainy season month to 1.55 ± 0.193 in December, a hot-wet season month. Lamb mortalities constituted the greater part of outflows. High lamb mortalities occurred in hot-wet (December), hot-dry (September) and post-rainy (April) seasons. There was a significant interaction between season and age of sheep on body weight of sheep. Highest (p < 0.05) body weights were recorded in the post-rainy and autumn season in both lambs and ewes. It is therefore very important to come up with affordable interventions which take into play ecological differences of the areas for improved nutritional status of sheep in communal areas which will lead to improved sheep productivity and the poor-resourced farmer human nutritional and livelihood.

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