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The Guatemala Rabbit Project: A household agricultural intervention program evaluation using the RE-AIM frameworkGraves, Jessica Martin 13 May 2022 (has links) (PDF)
Amongst the breathtaking and mountainous landscapes of the Western Highlands is a highly indigenous Mayan population stricken with challenges of food insecurity and extreme poverty. Despite efforts by governmental and non-governmental organizations alike to combat these challenges, the results of chronic malnutrition have led to some of the highest child stunting rates in all of Guatemala, particularly in the department of Totonicapán, where this study took place. To date, information is limited regarding agricultural programs that utilize the rabbit as a model to reduce food insecurity in Guatemala. Thus, a novel agricultural education program, Guatemala Rabbit Project (GRP), was developed using a farm-to-fork and hands-on training approach to provide women with knowledge and skills needed to successfully raise rabbits for household consumption. The overarching purpose of this study is to evaluate the GRP as an agricultural intervention among women in three Western Highlands communities. The REAIM evaluation framework, developed for and widely utilized to evaluate public health interventions, was used to assess reach, effectiveness, adoption, implementation, and maintenance of the GRP among participants. The first aim of this study was to conduct a process evaluation utilizing reach, adoption, and implementation dimensions of RE-AIM. Findings suggest that the target population was reached, and adoption rates (84%) were promising. In general, GRP adopters adhered to the best management practices taught during the training, as reflected by observational scores across a variety of management topics indicating successful implementation. The second study aimed to evaluate the outcomes of the GRP utilizing effectiveness and maintenance dimensions of RE-AIM. Findings suggest that the GRP could serve as a household agricultural intervention based on the reported benefits and positive unintended outcomes discovered. Participants provided feedback about challenges that will be used to expand training content. Overall, findings provide evidence that the GRP could be a sustainable agricultural intervention, increasing access to animal protein while also providing households with an additional source of income.
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Determination of the primary levels of the residues of the seeds of wheat, maize, and barley for the elaboration of the food mixture for rabbitsMorejon Jacome, Aida Esperanza 01 January 2006 (has links) (PDF)
The present investigation was done in the parish of Chaltura, Granja "La Pradera" which belongs to the University Técnica del Norte. The main objective of this investigation was to determine the primary levels of the residues of the seeds of wheat, maize, barley for the elaboration of the food mixture for rabbits. The evaluated variables, food consumed, weight gain, food value, protein percentage, production cost per treatment. Previously to the initiation of the field phase bromatological analysis were done on the three food mixtures in the National Institute of Farming Investigation, Quality and Nutrition Area. The treatments were four: TI 13.84% of protein, T2 15.87% of protein, T3 19.57% of protein, T4 (Testigo) 18% of protein The field phase lasted 90 days and 48 rabbits of the New Zealand race were used, 50% males, 50% females each of 45 days old. A randomly design was used with four treatments and six repetitions, also in the different determined significant cases between the used treatments in the Tukey 5% test From the analysis obtained the results were to administer food with a low level of protein, animal consume a major quantity like we can observe in the results of the TI which has 13.84% of protein raising the production costs, while in the major treatment the T2, which has 15.87% of protein, because of its composition it was good tasting for the animals, making the consumption of the food will increase the normal weight, and the cost of production per Kg. Of food is $0.28. The T3 has 19.57% of protein the same which is in excess since the animals only assimilate what they need and the rest is the cost of production per Kg. Of food is $0.28. The T3 has 19.57% of protein the same which is in excess since the animals only assimilate what they need and the rest is waste, besides raising the protein level, this raises the cost of the food mixture. And the commercial food the T4 (Testigo) had reasonable results, in the food consumption of the pellet food mixture like the weight increase, but it is not recommended for farming families for the cost of Kg. $0.40, giving also another alternative like the T2(15.87% of protein) with a cost of Kg. Of $0.28. Besides the experimental mixtures to the animals water was supplied and 150 gr. Of alfalfa in the afternoon on a daily basis. An enabling study was done about the raising of rabbits, and the elaboration of the food mixtures in the various families of the Agualongo, Chimbaloma, Pucará, Peguche, Imbaya, Iluman, Compania, Agato, Calpaqui, Punyaro, Quinchuqui, communities, all belonging to Antonio Ante and Otavalo.
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Study of livestock production levels in three communities near the city of RiobambaNuñez Lopez, Raul Rolando 01 January 1997 (has links) (PDF)
This study was done by administering household surveys to 50% of the families in the three communities. Families were selected through stratified random sampling. This allowed us to determine how much families are exploiting species that have a significant level of production as well as whether they use them for a commercial activity or subsistence. With regard to cows, 60.40 ± 4.72% of families use them. Each family has an average of 1.68 ± 0.21 cows. Productive cows make up 36.9% of the above percentage, which is a majority. The measured rate of production was 6.48 ± 0.25 L/cow/day. Overall, 40.16 ± 3.17% of production was used for household consumption while the rest was sold. These parameters as well as the sale of live animals helped San Nicolas have an annual income of 735 US dollars, which shows that this community relies more on commercial activity. On the other hand, San Clemente and San Francisco had annual incomes of 367 and 279 US dollars respectively. This shows that these communities focus more on familial subsistence. Of the major species, sheep are the least exploited with 54.80 ± 8.74% of families using them. The first lambing occurs at 17.79 ± 0.48 months. Newborns are weaned at 5.57 ± 0.11 months by only 27.27 ± 4.47% of families. Of the weaned newborns, 60.69 ± 5.13% are kept and the rest are sold. Every 10.46 ± 0.47 months, 77.96% of the wool produced is sold. Generally, the sheep are sol d at 22.84 ± 1.75 months of age. This generates an average annual income of 40.85 ± 19.26 US dollars, which indicates that this activity is focused on familial subsistence. Swine production is the most common form of animal production. Pigs are exploited by 81.86 ± 7.17% of families with each family having an average of 2.11 ± 0.16 animals. A sow’s first delivery occurs at 16.48 ± 0.48 months and their productive life comes after reproducing 1.98 ± 0.15 times. Each litter has 5.72 ± 0.19 offspring with a post-weaning mortality rate of 28.99 ± 4.82%. Offspring are weaned at 2.90 ± 0.12 months. Overall, 65.13% of the weaned offspring are kept and the rest are sold. Annual revenue from pig production is 63.2 ± 22.46 US dollars which indicates it is used for familial subsistence, acting as a safeguard against economic emergencies at times. Of the minor species, the guinea pig is the most exploited. It is used by 86.11 ± 3.65% of families with each family having an average of 12.04 ± 1.31 guinea pigs. The mothers have an average of 2.44 ± 0.06 offspring per litter with a weaning rate of 75.81 ± 4.33%. Overall, 86.91% of production is used for family consumption and the rest is sold. The annual income generated by this activity is 6.24 ± 0.51 US dollars which indicates that this is an activity dedicated to providing food for the family. Rabbits are used by 49.42 ± 5.23% of families, each having an average of 4.03 ± 0.64 animals. There is an average of 6.57 ± 0.29 newborns per litter with a weaning rate of 41.16 ± 5.20%. Overall, 80.18 ± 4.16% of production is used for family consumption. This activity is similar to guinea pig production seeing as the annual income it generates is only 12.80 ± 1.10 US dollars. Chickens are exploited by 77.33 ± 4.39% of families with each family having an average of 5.88 ± 0.60 animals. Broiler chickens make up 48.22% of the poultry population with the rest being made up of native and field hens. Overall, 68.96% of broiler chickens are used for family consumption while 89.31 ± 3.27% of hens are used for family consumption. The annual income from this activity is 40.13 ± 19.24 US dollars. This makes it appear to have a slight tendency toward commercial use. We conclude that the three communities have different levels of animal exploitation. San Nicolas was the most successful of the three, partially using their livestock production for commercial purposes. San Clemente used part of theirs for commercial purposes as well, but on a lower scale. San Francisco, on the other hand, focuses their livestock production solely on familial subsistence. We recommend that a study be conducted regarding all points involved in the feasibility of production projects in these communities, especially in regard to the organization in each community. This will help improve production levels and make way for a change from a subsistence based economy to a more commercially based economy, ultimately improving the social and nutritional levels of these families.
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Evaluation of intensified rabbit management procedures on public hunting area in southcentral VirginiaKrug, Alan Scott 15 November 2013 (has links)
This study, concerned with evaluation of Cottontail Rabbit management techniques, was conducted at Camp Pickett, Virginia, a 47,000-acre deactivated military reservation. This public hunting area is managed cooperatively by the U. S. Second Army and the Virginia Commission of Game and Inland Fisheries.
Cottontail Rabbit population fluctuations were measured by roadside counts during the summer months. It was found that a precipitous drop in the rabbit population occurred in mid-August. The suspected etiology of this population drop was disease, although no research data were collected to substantiate this theory.
Land-cultural treatments were calculated by means of pellet counts and live-trapping. The treatments extant on Camp Pickett are installation of annual game bird mix and clover-small grain food patches, seeding of firelanes in fescue and clover-fescue combination, burning and mowing.
Summer pellet counts showed the rabbit to be utilizing the annual mix food patches more than any other treatment type. The clover-small grain food patch was next in preference. Utilization of the remaining treatment types, which were mostly located in forested area, was rather low.
Fall trapping data revealed a switch to the clover-small grain management unit, with the annual mix running second. Utilization of the other treatment types was again low.
Winter trapping data showed an even greater preference for the clover-small grain than was found in the fall.
Spring pellet count data resembled that obtained in the previous summer, with the exception of the burned areas, which received substantial usage by the rabbit. Differences between spring pellet count data and winter trapping data are believed due to an accumulation of older pellets. A pellet durability study showed winter loss of pellets to be minimal.
An attempt to evaluate various population estimation formulae by live-trapping a known cottontail population in a five-acre enclosure met with failure when deer knocked down the fence, hunters poached, and rabbits were lost from various other causes, often unknown.
A record was kept of all parasites, disease and injury encountered in the rabbit population. Forty-two per cent of all rabbits handled either were or presented evidence of having been infested with bot fly larvae. An incidence of 2.2 per cent of Shope's fibroma was found.
A record was kept of all cottontail deaths known to have been caused by motor vehicles. The number of deaths per mile of highway traveled became progressively higher through the months of July to April, even though the rabbit population became progressively lower. This increasing highway kill was apparently due to the increased movement required of the rabbit in the winter months when food and cover are scarce, and the increased movement that occurs among the rabbit population when the spring breeding season arrives. / Master of Science
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ANÁLISIS GENÉTICO DE LA GRASA INTRAMUSCULAR EN CONEJO-GENETIC ANALISYS OF INTRAMUSCULAR FAT IN RABBITSZomeño, Cristina 15 July 2013 (has links)
En esta tesis se aborda el estudio de la grasa intramuscular como característica determinante de la calidad de la carne para ser utilizado en programas genéticos. El conejo se plantea no sólo por su interés como especie ganadera sino como modelo en otras especies. Este estudio se divide en tres experimentos, cada uno de ellos representa cada uno de los tres objetivos específicos de esta tesis:
1. Estudiar la variabilidad genética entre líneas de conejo de factores ligados directamente a la deposición de grasa tanto en músculo como en tejido adiposo, como son las enzimas que participan en la síntesis y degradación de la grasa y en la composición en ácidos grasos.
2. Puesta a punto de una calibración NIRS para estimar grasa intramuscular y la evaluación de su uso en programas de selección en conejo.
3. Selección divergente por grasa intramuscular. Estudio de las posibilidades de éxito de la selección por grasa intramuscular y conocer las relaciones genéticas entre caracteres examinando la respuesta correlacionada.
Supone el inicio de una nueva línea de investigación en metabolismo lipídico, que puede servir tanto a la producción de conejo como animal de carne como al uso del conejo como modelo experimental. Es la primera vez que se propone un experimento de selección divergente por grasa intramuscular. Este experimento permitirá conocer mejor las relaciones genéticas entre la grasa intramuscular, la grasa de la canal, así como las relaciones con otros caracteres productivos. El conocimiento de estas relaciones genéticas va a ser fundamental para futuros programas de mejora genética en todas las especies ganaderas. / Zomeño, C. (2013). ANÁLISIS GENÉTICO DE LA GRASA INTRAMUSCULAR EN CONEJO-GENETIC ANALISYS OF INTRAMUSCULAR FAT IN RABBITS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/31121
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Genomic analysis of divergently selected experimental lines in rabbitSosa Madrid, Bolívar Samuel 23 April 2020 (has links)
Tesis por compendio / [ES] La selección divergente puede cambiar las frecuencias de los marcadores genéticos en direcciones opuestas, produciéndose frecuencias alélicas intermedias en estos marcadores cuando ambas líneas divergentes son consideradas conjuntamente en los análisis genéticos. Por lo tanto, los experimentos de selección divergente aumentan el poder de detección para estudios de asociación de genoma completo (GWAS) y para estudios de escaneo genómico por medio de métodos de huellas de selección.
GWASs bayesianos, utilizando el modelo Bayes B, se implementaron para analizar datos genómicos de los caracteres de tamaño de camada del experimento de capacidad uterina con 181 hembras. Las asociaciones fueron evaluadas calculando los factores de Bayes para cada SNP, y calculando los porcentajes de la varianza genómica para cada ventana no solapada de 1-Mb. Los GWASs descubrieron SNPs asociados con el número total de gazapos al parto y los embriones implantados. Además, se revelaron regiones genómicas relevantes para el número total de gazapos al parto (1 región), el número de nacidos vivos (1 región), los embriones implantados (3 regiones) y la tasa de ovulación (5 regiones). Los porcentajes de varianza genómica que explicaban los anteriores caracteres de tamaño de camada fueron 39,48%, 10,36%, 37,21% y 3,95%, respectivamente, en un modelo que excluye el efecto línea; y 7.36%, 1.27%, 15.87% y 3.95%, respectivamente, en un modelo con el efecto línea. La región genómica localizada en el cromosoma del conejo (OCU) 17 en 70.0 - 73.3 Mb se consideró como un nuevo locus de carácter cuantitativo (QTL) asociado a caracteres reproductivos en conejos, ya que esta región fue encontrada solapada para el número total de gazapos al parto, el número de nacidos vivos y los embriones implantados. El gen de la proteína morfogenética ósea 4, BMP4, es el principal gen candidato prometedor dentro del nuevo QTL.
Una combinación de GWASs fueron implementados para analizar los datos genómicos del experimento de la grasa intramuscular con 480 conejos. Los métodos de GWASs incluyeron un método bayesiano, modelo Bayes B; y un método frecuentista, regresiones de marcadores únicos con los datos ajustados por el parentesco genómico. Este estudio reveló cuatro regiones genómicas relevantes en OCU1 (1 región), OCU8 (2 regiones) y OCU13 (1 región) asociadas con la grasa intramuscular. La región asociada más importante estaba en OCU8 en 24.59 - 26.95 Mb, y explicó el 7.34% de la varianza genómica. El bajo porcentaje explicado por las principales regiones genómicas relevantes indica un gran componente poligénico para la grasa intramuscular. Los análisis funcionales recuperaron genes vinculados con las rutas y funciones de los metabolismos de energía, carbohidratos y lípidos. Además, se realizó un estudio de escaneo genómico usando conejos del experimento de selección divergente para grasa intramuscular, y usando tres métodos de firmas de selección: índice de fijación de Wright (Fst), coeficiente de verosimilitud compuesto entre poblaciones (XP-CLR) y extensión de homocigosidad de los haplotipos entre poblaciones (XP-EHH). Los resultados mostraron múltiples huellas de selección en todo el genoma del conejo. Ninguna de estas huellas de selección concuerda con las regiones genómicas asociadas con la grasa intramuscular, provenientes de los resultados de los GWASs. En síntesis, los resultados de ambos experimentos, GWASs y el estudio de escaneo genómico, sugieren que la arquitectura genómica de la grasa intramuscular en el conejo parece ser altamente poligénica y sus variantes causales serían apenas detectables.
Este estudio demuestra que la detección de variantes causales y marcadores genéticos asociados depende de las hipotéticas arquitecturas genómicas de los caracteres, independientemente de las exitosas respuestas logradas en los dos experimentos de selección divergente. Hasta la fecha, estos hallaz / [CA] La selecció divergent pot alterar les freqüències dels marcadors genètics en direccions oposades, donant lloc a freqüències al·lèliques intermèdies quan les dos línies divergents es consideren conjuntament en els anàlisis genètics. Per tant, els experiments de selecció divergents augmenten el poder de detecció en estudis d'associació de genoma ampli (GWAS) i en estudis d'exploració genòmica a través de mètodes de signatures de selecció.
GWASs bayesians, utilitzant el model Bayes B, es van implementar per a analitzar dades genòmiques de caràcters de grandària de ventrada de l'experiment de capacitat uterina amb 181 conilles femelles. Les associacions es van provar calculant els factors de Bayes per a cada SNP, i calculant els percentatges de la variància genòmica per a cada finestra no superposada d'1-Mb. Els GWASs van descobrir SNPs associats amb el número total de llorigons al part i els embrions implantats. A més, es van revelar regions genòmiques rellevants per al número total de llorigons al part (1 regió), el número de nascuts vius (1 regió), els embrions implantats (3 regions) i la taxa d'ovulació (5 regions). Els percentatges de variància genòmica que explicaven els anteriors caràcters de grandària de ventrada van ser 39,48%, 10,36%, 37,21% i 3,95%, respectivament, sota un model que exclou l'efecte de línia; i 7.36%, 1.27%, 15.87% i 3.95%, respectivament, sota un model amb efecte de línia. La regió genòmica situada en el cromosoma del conill (OCU) 17 en 70.0 - 73.3 Mb es va considerar com un nou locus de caràcters quantitatius (QTL) associat a caràcters reproductius en conills, ja que aquesta regió es va superposar per al número total de llorigons al part, el número de nascuts vius i els embrions implantats. El gen de la proteïna morfogenètica òssia 4, BMP4, és el principal gen candidat prometedor dins del nou QTL.
Una combinació de GWASs es van implementar per a analitzar les dades genòmiques de l'experiment del greix intramuscular amb 480 conills. Els mètodes GWASs van incloure un mètode bayesià, model Bayes B; i un mètode frecuentista, regressions de marcadors únics amb les dades ajustades pel parentiu genòmico. Aquest estudi va revelar quatre regions genòmiques rellevants en OCU1 (1 regió), OCU8 (2 regions) i OCU13 (1 regió) associades amb el greix intramuscular. La regió associada més important estava en OCU8 en 24.59 - 26.95 Mb, i va explicar el 7.34% de la variància genòmica. El baix percentatge explicat per les principals regions genòmiques rellevants indica un gran component poligènic per al greix intramuscular. Els anàlisis funcionals van recuperar gens relacionats amb les rutes i la funció d'energia, metabolismes de carbohidrats i lípids. A més, es va realitzar un estudi d'exploració del genoma usant conills de l'experiment de selecció divergent per a greix intramuscular, i usant tres mètodes de signatures de selecció: índex de fixació de Wright (Fst), coeficient de versemblança compost entre poblacions (XP-CLR) i extensió de homocigosidad dels haplotipos entre poblacions (XP-EHH). Els resultats van mostrar múltiples petjades de selecció en tot el genoma del conill. Cap d'aquestes petjades de selecció concorda amb les regions genòmiques associades a partir dels resultats dels GWASs. En síntesi, els resultats dels dos experiments, GWASs i estudi d'exploració del genoma, suggereixen que l'arquitectura genòmica del greix intramuscular en el conill sembla ser altament poligènica i les seues variants causals serien a penes detectables.
Aquest estudi demostra que la detecció de variants causals i marcadors genètics associats depèn de les hipotètiques arquitectures genòmiques dels caràcters, independentment de les respostes reeixides en els dos experiments de selecció divergents. Fins ara, aquestes troballes no tindrien implicacions valuoses per als programes de cria de conills. / [EN] Divergent selection can alter frequencies of genetic markers in opposite directions, leading to intermediate allelic frequencies when both divergent lines are jointly considered in the genetic analyses. Therefore, divergent selection experiments increase the detection power for genome wide association studies (GWAS) and for genomic scan studies through methods of selection signatures.
Bayesian GWASs using Bayes B model was used to analyse genomic data of litter size traits of the uterine capacity experiment with 181 does. The associations were tested by computing Bayes factors for each SNP, and by computing percentages of the genomic variance for each 1-Mb non-overlapping window. The GWASs uncovered SNPs associated with total number born and implanted embryos. Moreover, relevant genomic regions were revealed for total number born (1 region), number born alive (1 region), implanted embryos (3 regions), and ovulation rate (5 regions). The percentages of genomic variance that accounted for these litter size traits were 39,48%, 10.36%, 37.21%, and 3.95%, respectively, under a model excluding line effect; and 7.36%, 1.27%, 15.87%, and 3.95%, respectively, under a model with line effect. The genomic region located on the rabbit chromosome (OCU) 17 in 70.0 - 73.3 Mb was deemed as a novel quantitative trait locus (QTL) of reproductive traits in rabbits, since this region was found overlapped for total number born, number born alive and implanted embryos. Bone morphogenetic protein 4 gene, BMP4, is the main promising candidate gene within the novel QTL.
A combination of GWASs were performed for analysing the genomic data of the intramuscular fat experiment with 480 rabbits. The GWAS methods included a Bayesian method, Bayes B model; and a frequentist method, single marker regressions with the data adjusted by genomic relatedness. This study revealed four relevant genomic regions in OCU1 (1 region), OCU8 (2 regions) and OCU13 (1 region) associated with intramuscular fat. The most important associated region was on OCU8 in 24.59 - 26.95 Mb, and accounted for 7.34% of the genomic variance. The low percentage explained by the main relevant genomic regions indicates a large polygenic component for intramuscular fat. Functional analyses retrieved genes linked to pathways and function of energy, carbohydrate and lipid metabolisms. In addition, a genome scan study was performed using rabbits from the divergent selection experiment for intramuscular fat, and using three methods of selection signatures: Wright's fixation index (Fst), cross population composite likelihood ratio (XP-CLR) and cross population extended haplotype homozygosity (XP-EHH). The results showed multiple selection signatures across the rabbit genome. None of these selection signatures agreed with the associated genomic regions from GWAS findings. In synthesis, the results of both experiments, GWAS and genome scan study, suggest that the genomic architecture of intramuscular fat in rabbit seems to be highly polygenic and their causative variants would be hardly detectable.
This study demonstrates that detection of causative variants and associated genetic markers depends on the hypothetical genomic architectures of traits, regardless of the successful responses attained in the two divergent selection experiments. Hitherto, these findings would not have worthwhile implications for the rabbit breeding programs. / Sosa Madrid, BS. (2020). Genomic analysis of divergently selected experimental lines in rabbit [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/141376 / Compendio
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Amine functional hydrogels as selective substrates for corneal epithelializationHassan, E., Deshpande, P., Claeyssens, F., Rimmer, Stephen, MacNeil, S. 07 1900 (has links)
No / The aim of this study was to develop a synthetic hydrogel to act as a corneal substitute capable of selectively supporting the adhesion and proliferation of limbal epithelial cells (LECs) while inhibiting growth of limbal fibroblasts. Deficiency of LECs causes conjunctival epithelial cells to move over the cornea, producing a thick scar pannus. Unilateral defects can be treated using LEC cultured from the unaffected eye, transplanting them to the affected cornea after scar tissue is removed. The underlying wound bed is often damaged, however, hence the need to develop a corneal inlay to aid in corneal re-epithelialization. Transparent epoxy-functional polymethacrylate networks were synthesized using a combination of glycerol monomethacrylate, ethylene glycol dimethacrylate, lauryl methacrylate and glycidyl methacrylate that produced two different bulk hydrogel compositions with different equilibrium water contents (EWCs): Base 1 and Base 2, EWC=55% and 35%, respectively. Two sets of amine-functional hydrogels were produced following reaction of the epoxide groups with excesses of either ammonia, 1,2-diamino ethane, 1,3-diamino propane, 1,4-diamino butane or 1,6-diamino hexane. Neither series of hydrogels supported the proliferation of limbal fibroblasts irrespective of amine functionalization but they both supported the adhesion and proliferation of limbal epithelial cells, particularly when functionalized with 1,4-diamino butane. With Base 1 hydrogels (less so with Base 2) a vigorous epithelial outgrowth was seen from small limbal explants and a confluent epithelial layer was achieved in vitro within 6days. The data support the development of hydrogels specific for epithelial formation.
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Distribution Dynamics of Swamp Rabbits (Sylvilagus aquaticus) in MissouriBosch, Kylie 01 August 2024 (has links) (PDF)
Swamp rabbits (Sylvilagus aquaticus) are a bottomland hardwood forest specialist undergoing contraction at the northern extent of their range. This decline is often attributed to the loss of bottomland hardwood forest and frequent, intense flooding. To mitigate this decline and inform decisions regarding the swamp rabbit’s conservation status, there is a pressing need for long-term monitoring efforts. Although currently listed as imperiled (S2) in Missouri, shifts in occupancy trends may warrant a reassessment of the swamp rabbit’s state rank. The Missouri Department of Conservation has conducted decadal surveys for swamp rabbits since 1991, and the work presented here describes the fourth iteration of this study – 2022-2023. Repeated latrine surveys at 176 previously surveyed sites were conducted from November 2022 – April 2023 across 16 counties in southeast Missouri. Dynamic occupancy models were then used to estimate occupancy, colonization, extinction, and detection probabilities and identify environmental factors driving distribution changes since 2012. Additionally, I examined the impact of including ground latrines in swamp rabbit detection histories for the 2022-2023 survey season in a comparative single-season occupancy analysis. This analysis aimed to evaluate how the incorporation of ground latrines, as opposed to restricting detections to latrines on elevated surfaces, influenced estimates of occupancy and detection probabilities. Swamp rabbits were detected at 148 sites in 15 counties in 2022-2023, with a noted increase in occupancy probability from 0.66 (SE = 0.01) in 2010-2012 to 0.79 (SE = 0.01) in 2022-2023. As expected, site isolation negatively impacted occupancy probability, but predictors for patch richness density, site area, flood frequency, and flood severity had varying levels of support. For example, occupancy probability was negatively influenced by patch richness density but positively influenced by site area, while colonization probabilities were high and positively influenced by both flood frequency and severity. Extinction probability was low but was negatively influenced by flood frequency. Models with occupancy, colonization, and extinction as a function of the proportion of bottomland hardwood forest at a site were not supported. Detection probability decreased from 0.90 (SE = 0.19) in 2010-2012 to 0.78 (SE = 0.13) in 2022-2023. The inclusion of ground latrines in analyses did increase detection (0.68 to 0.84) and estimates of occupancy probabilities (0.95 to 1.00) but the change in estimates of occurrence was not biologically meaningful. Despite concerns about decline at the northern edge of their range, swamp rabbit populations in southeast Missouri appear to be expanding, evidenced by the increased occupancy and promising colonization and extinction rates. While long-term monitoring efforts should continue, managers should consider changing the swamp rabbit’s state rank from imperiled (S2) to vulnerable (S3).
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Emprego de membrana de celulose microfibrilar na ceratoplastia lamelar em coelhos (O. cuniculus, Linnaeus, 1758) : aspectos clínicos, morfológicos e imunoistoquimicos /Macedo, Luciana Ricciardi. January 2008 (has links)
Orientador: José Luiz Laus / Banca: Auero Evangelista Santana / Banca: Thiago Luiz de Salles Gomes / Resumo: Avaliaram-se descritivamente, à clínica, à histopatologia e à imunoistoquímica (ki 67- marcador de proliferação celular) os resultados, da cicatrização da córnea, após ceratoplastias lamelares com membrana de celulose microfibrilar em coelhos. Para tal, utilizaram-se 30 coelhos , distribuídos em 5 grupos de 6 animais, avaliados por até 60 dias de pós operatório. A avaliação clínica revelou manifestações moderadas de edema, blefaroespasmos, fotofobia desde o segundo dia, evoluindo para formas discretas ou ausentes a partir do sétimo dia, onde observou-se clinicamente o reparo do defeito da córnea. A histopatologia revelou uma fina camada de células escamosas, recobrindo totalmente a área lesada, aos sete dias, e com leve infiltrado de células polimorfonucleares. Observou-se a presença de vasos no epitélio a partir do 15º dia , com regressão aos 48º dias .A imunoistoquímica mostrou aumento de células em proliferação aos 15 dias no epitélio (p= 0,049) e aos trinta dias no estroma (p= 0,042). Frente aos resultados obtidos, há como admitir que mesmo com o defeito corneal concluído, aos sete dias, o sistema de defesa celular ainda se manteve ativo, pois a proliferação celular no epitélio se mostrou mais intensa aos 15 dias de observação ,conforme demonstrado imunoistoquimicamente. Onde nesse período ocorreu remodelamento e adesão epitelial da córnea, características satisfatórias em ceratoplastia lamelar em coelhos . / Abstract: Were evaluated the clinic, the histopathology and immunohistochemistry (ki 67 - marker of cell proliferation), the results of the membrane of cellulose in lamellar keratoplasty in rabbits. To this end, 30 rabbits were used, divided into 5 groups of 6 animals, assessed by up to 60 days of post-operative. The assessment showed clinical manifestations of moderate swelling, blefarospasmos, photophobia since the second day, evolving into discrete forms or absent from the seventh day, where there was clinically repair the defect of the cornea. The histopathology revealed a thin layer of squamous cells, completely covering the injured area, the seven days, and with mild infiltration of polymorphonuclear cells. There was the presence of vessels in the epithelium from the 15 th day, with regression of days to 48. Immunohistochemistry showed increased cell proliferation in the 15 days in the epithelium (p = 0049) and the thirty days in the stroma (p = 0042) . Facing the results achieved, as there admit that even with the beginning of healing, and with the defect of the cornea closed to seven days, the system of defence cell remained active, as in the epithelial cell proliferation was more intense at 15 days, as shown imunoistochemistry. Where in that period showed epithelial remodeling and membership, characteristics satisfactory in lamellar keratoplasty in rabbits. / Mestre
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Conséquences d'un contrôle de l'ingestion sur la physiopathologie digestive et le comportement alimentaire du lapin en croissance / Consequences of a feed intake control on digestive physiopathology and on feeding behaviourMartignon, Mélanie 15 December 2010 (has links)
Les attentes sociétales s’orientent vers une consommation saine, et provenant de systèmes agricoles durables. En filière cunicole, la maîtrise des pathologies digestives nécessite le recours à l'antibiothérapie curative ou préventive. La recherche d’alternatives à l’utilisation d’antibiotiques en élevages cunicoles est donc primordiale pour augmenter la durabilité de cette production. Les stratégies de limitation de la quantité d’aliment ingérée sont une des solutions possibles à ce problème, puisqu'elles améliorent la résistance du jeune lapin aux troubles digestifs. Ce travail de thèse a pour objectif d’étudier les mécanismes sous-jacents à cet effet favorable des stratégies de rationnement, et aussi d'analyser le comportement alimentaire du lapin restreint en relation avec son bien-être. Cet objectif se scinde en deux parties étudiées. La première partie a pour but de déterminer quelle caractéristique de la restriction alimentaire limite les troubles digestifs en engraissement. La seconde partie s’intéresse aux paramètres biologiques potentiellement influencés par cette stratégie d’alimentation. Les paramètres considérés sont reliés à plusieurs domaines de biologie : enzymologie, histométrie, écosystème bactérien cæcal. Une restriction de l'ingéré de -25% réduit la croissance mais améliore significativement l’efficacité digestive (de 4 à 6% entre 28 et environ 50 jours d'âge) des lapins en engraissement, qui peut s'expliquer par une plus forte digestibilité des fractions protéique (4,5%), énergétique (5,3%) et fibreuses (NDF : 8,9%, ADF : 9,7%, hémicelluloses: 7,9%, cellulose : 11,5%). Cependant, la structure, la diversité et la densité de la communauté bactérienne cæcale sont peu modifiées chez l'animal restreint sain. Des modifications du comportement alimentaire ont été soulignées au cours de ce travail. Ainsi, le rythme d’ingestion, fonction du rythme nycthéméral pour les lapins nourris à volonté, est dépendant du moment de distribution de l’aliment pour les animaux restreints. Après 18 jours de restriction, les lapins ingèrent un tiers de la quantité qui leur est distribuée en 2 heures, et la totalité en moins de 10 heures. Mais aucune agressivité ou compétition n’a été observée entre les animaux restreints. Plusieurs pistes peuvent expliquer l’efficacité de cette stratégie d’alimentation sur la santé digestive du lapereau. Ainsi, les résultats obtenus au cours de la reproduction d’une colibacillose (Escherichia coli O128:C6) suggèrent une stabilisation de l’écosystème iléal par la restriction alimentaire après l’infection. D'autre part, au niveau cæcal l'activité des communautés bactériennes serait modulée, même si pour ce modèle, l'effet d'une ingestion limitée semble faible sur le statut sanitaire. Enfin, l’alternance de périodes de satiété et de périodes de faim stimule la libération sanguine d’hormones (ghréline notamment) qui pourraient moduler la fonction immunitaire. En perspectives, il serait pertinent d'étudier plus précisément les fonctions liées au statut immunitaire ou endocrinologique. De plus, l'étude plus approfondie de la communauté bactérienne cæcale, en ciblant certaines espèces, pourrait apporter un complément d’informations sur les interactions entre ingestion et symbiote digestif et lors d'une approche comparée de 2 modèles pathogèniques : EPEC vs. EEL. / Societal expectations are moving towards healthy food from sustainable farming systems. In rabbit industry, control of digestive diseases requires the use of curative or preventive antibiotics. The search for alternatives to the use of antibiotics in rabbit breeding is thus crucial to improve sustainability of this production. Strategies for limiting the amount of feed ingested are one possible solution to this problem, since they improve the digestive resistance of young rabbits. This thesis aims to study the mechanisms underlying this positive effect of restriction strategies, and also to analyze the feeding behaviour of restricted rabbit in relation to their welfare. This objective is divided into two parts. The first part aims to determine which characteristic of feeding restriction limits the digestive disorders in fattening. The second part deals with the biological parameters potentially influenced by this feeding strategy. The parameters considered are related to several areas of biology: enzymology, histometry, digestive bacterial ecosystem A reduction of feed intake of -25% reduced growth, but significantly improved digestive efficiency (4 to 6% between 28 and 50 days old) of fattening rabbits which can be explained by a higher protein digestibility (4.5%), energy (5.3%) and fibres (NDF: 8.9%, ADF: 9.7%, hemicellulose 7.9%, cellulose: 11.5%). However, the structure, diversity and density of the caecal bacterial community are little changed in the healthy animal fed restricted. Changes in eating behaviour were highlighted during this work. Thus, the rhythm of intake, depending on the circadian rhythm in rabbits fed ad libitum, is function of the feed distribution time for restricted animals. After 18 days of restriction, rabbits ingest in 2 hours the third of the quantity supplied, and the entire amount within 10 hours. No aggression or competition was observed between animals. Several hypotheses could explain the effectiveness of this strategy on digestive health in young rabbit. Thus, the results obtained during the reproduction of colibacillosis (Escherichia coli O128: C6) suggest a stabilization of the ileal ecosystem after infection. On the other hand, the main activity of bacterial communities of caecum would be modulated, even if for this model a limited intake moderately modified the sanitary status. Finally, the alternation of periods of satiety and hunger may stimulate the release of hormones (e.g. ghrelin) that could modulate immune function. In perspective, it would be appropriate to study more precisely the functions related to immune or endocrine status.In addition, a deeper study of the caecal bacterial community by targeting some species could provide additional informations on the interactions between intake and digestive symbiote, and on a comparative approach of the two pathogenic models: EPEC vs. REE.
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