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The social and ecological significance of nursery groups in wild giraffe / 野生キリンにおける仔育て集団の社会的・生態的重要性Saito, Miho 25 March 2019 (has links)
付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21613号 / 理博第4520号 / 新制||理||1649(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 伊谷 原一, 教授 村山 美穂, 教授 平田 聡 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
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EARLY LIFE CALF NUTRITION AND MANAGEMENT AND THEIR IMPACTS ON HEALTH AND PRODUCTIVITYRebecca N Klopp (11767772) 03 December 2021 (has links)
<p>The first four months of a dairy
calf’s life provide the foundation for future production and health. Therefore,
it is critical that calves are managed to optimize both health and growth, to
maximize their potential. Calf morbidity, which leads to less productive
animals and is an economic impact on producers, continue to be areas of
opportunity in the dairy industry. In addition, the animal agricultural
community is working to reduce the use of antibiotics, due to a growing concern
regarding antibiotic resistant bacteria. This provides researchers with the
challenge of identifying strategies to reduce calf morbidity and mortality,
while also decreasing reliance on antibiotics. The objective of this dissertation
was to evaluate nutritional strategies supplemented to calves as well as
maternal factors that impact colostrum. The studies focused on strategies to improve
the innate and adaptive immune responses and growth of the calf, ultimately
reducing reliance on antibiotics. Chapters 2 and 3 discuss feeding dairy calves
<i>Saccharomyces cerevisiae</i> fermentation products in milk replacer and
solid feeds until 4 months of age. This study concluded that feeding <i>Saccharomyces
cerevisiae</i> fermentation products to calves improves average daily gain and feed
efficiency post-weaning and reduces antibiotic treatment incidence for respiratory
disease. It also increases the evenness of the fecal microbiome and the acute innate
immune response, as determined by increased TNF-α, glucose, and respiration
rate during a lipopolysaccharide challenge. Chapter 4 evaluated the effects of
feeding dairy calves medium chain fatty acids (C8:0 and C10:0) in milk replacer
until 60 days of age. Feeding C8:0 and C10:0 to calves reduced plasma NEFA
concentrations around weaning, suggesting the mobilization of less adipose
tissue to meet the energy demands of the calf. This trial also determined that vaccinating
calves at 3 weeks of age with ovalbumin combined with an aluminum hydroxide
adjuvant, is an effective way to evaluate their adaptive immune responses. </p>
<p>Supplementing calves directly is
not the only way to impact calf growth and health, maternal factors also impact
calf nutrition through colostrum consumption. Last, chapter 5 explored maternal
factors that influence the lipidome of colostrum and therefore the lipid intake
of the newborn calf. This study concluded that the metabolic status of the cow affects
circulating lipids and the lipid content of colostrum. Also, the lipidome of colostrum
is distinct from the circulating lipidome of the calf, which is similar to the
circulating lipidome of the cow, except for phosphatidylglycerol, where it
appears that colostrum serves as the source for the phosphatidylglycerol present
in the circulation of the calf. There are many different nutritional strategies
that can impact the health and productivity of calves. Calves can be directly
supplemented with nutraceuticals like <i>Saccharomyces cerevisiae</i>
fermentation products or medium chain fatty acids, or calf nutrition can be
influenced by the maternal factors through the consumption of colostrum. </p>
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North Dakota Beef Cow Operators: Identifying Current Management Practices and Factors that Influence Adoption Rates of Best Management Practices Relating to Surface Water PollutionVan Winkle, Andrea January 2011 (has links)
Best management practices are methods that have been determined to be the most effective and practical means of preventing or reducing pollution. Best Management Practices (BMPs) relating to surface water pollution abatement for North Dakota beef cow operations are of particular importance due to the importance of the agriculture industry in North Dakota. North Dakota has yet to address the use of voluntary BMPs to address potential surface water pollution regulations. Probit models were used to estimate the likelihood of North Dakota beef cow operators adopting specific production practices to reduce potential surface water pollution through the use of BMPs. The six BMPs discussed in this research include nutrient management, rotational grazing, filterstrjps, riparian buffers, streambank fencing, and streambank bridging/crossing. Number of beef cows on operation, education, awareness of cost share programs, contact with extension service, ownership structure, debt level, record keeping method, and pasture season usage were found to be significant in the likelihood of adopting a BMP.
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Studien zur Behandlung der Eimeria bovis - Kokzidiose des Kalbes mit ToltrazurilUebe, Friederike 11 October 2011 (has links)
Ziel der vorliegenden Arbeit war es, ein Infektionsmodell für Eimeria bovis zu etablieren und die induzierte Kokzidiose mit unterschiedlichen Anwendungen von Toltrazuril zu behandeln. Zusätzlich wurde eine histopathologische Studie durchgeführt, in der zu unterschiedlichen Zeitpunkten mit der gleichen Dosis Toltrazuril behandelt wurde.
In der ersten Studie wurde die effektive Dosis Toltrazuril bei einer experimentellen E. bovis – Kokzidiose bestimmt. Nach der experimentellen Infektion mit 50000 Oozysten pro Kalb wurden die Tiere mit 5, 15 oder 25 mg/kg LM Toltrazuril oder mit einem Plazebo in der Präpatenz behandelt. In der Plazebogruppe entwickelten alle Tiere Durchfall, zwei Tiere auch hämorrhagische Diarrhoe. In den Behandlungsgruppen trat keine hämorrhagische Diarrhoe auf, sondern im Fall klinischer Kokzidiose nur katarrhalischer Durchfall. Auch in der durchschnittlichen Erkrankungsdauer unterschied sich die Plazebogruppe von den Behandlungsgrupppen ( 9,1 Tage bzw. 4,6, 4,3 oder 3,3 Tage). Bei der Oozystenausscheidung war ebenfalls ein statistisch signifikanter Unterschied zwischen der Plazebogruppe und den Behandlungsgruppen nachweisbar; ebenfalls war ein statistisch signifikanter Unterschied der Oozystenausscheidung der mit 5 mg/kg LM und den mit 15 bzw. 25 mg/kg LM behandelten Kälbern nachweisbar. Das Gewicht unterschied sich in dieser Studie nicht statistisch signifikant, was vermutlich auf die geringen Tierzahlen und begleitende Atemwegserkrankungen zurückzuführen ist.
In der zweiten Studie wurde die Infektionsdosis auf 100000 Oozysten pro Kalb verdoppelt und zwei Behandlungsgruppen gebildet: unbehandelte Kontrollgruppe und 15 mg/kg LM Toltrazuril. Auch in dieser Studie traten signifikante Unterschiede zwischen den Gruppen auf. Dies betraf Kotkonsistenz, Oozystenausscheidung und Gewicht. Die unbehandelten Kälber wiesen alle hämorrhagische Diarrhoe mit Gewebefetzen auf, in der Behandlungsgruppe trat dies nur bei einem Tier auf, alle anderen Kälber wiesen nur eine katarrhalische Diarrhoe auf. Alle Tiere (n=9) der Kontrollgruppe schieden erhebliche Mengen von Oozysten aus, bei den behandelten Tieren schieden nur 2 von 9 Kälbern Oozysten aus, auch die OpG lagen deutlich niedriger.
In der dritten Studie mit histopathologischer Untersuchung wurden die Tiere in drei Gruppen aufgeteilt, die jeweils aus 8 Tieren bestanden; alle Tiere wurden mit 100000 Oozysten pro Kalb infiziert. Eine Gruppe erhielt in der Präpatenz eine Plazebobehandlung, eine in der Präpatenz metaphylaktisch 15 mg/kg LM Toltrazuril und eine therapeutisch 15 mg/kg LM Toltrazuril. Die Untersuchungstermine für die Pathologie wurden in der Präpatenz und der frühen und späten Patenz, bzw. Postpatenz gewählt. Auch in dieser Studie unterschieden sich die Kotkonsistenz und die Oozystenausscheidung deutlich zwischen der metaphylaktisch behandelten Gruppe und den beiden anderen Gruppen. Auch die Gewichtszunahme lag in der metaphylaktisch behandelten Gruppe deutlich höher als in den beiden anderen Gruppen. Die pathologischen Ergebnisse zeigen ebenfalls einen deutlichen Unterschied zwischen der metaphylaktisch behandelten Gruppe und den beiden anderen Gruppen.
Insgesamt lassen die Ergebnisse den Schluß zu, daß eine metaphylaktische Behandlung mit Toltrazuril in der Lage ist, eine massive klinische Kokzidiose, hervorgerufen durch E. bovis, zu verhindern. Da eine therapeutische Anwendung keinen deutlichen Effekt auf die klinische Ausprägung und die Oozystenausscheidung zeigt, ist es in der Praxis wesentlich, mit der Epidemiologie in dem zu behandelnden Bestand vertraut zu sein, um eine effektive Behandlung zu ermöglichen. Durch eine Behandlung in der Präpatenz kann über die Verringerung der Ausscheidung von Oozysten der Infektionsdruck für nachfolgende Kälbergruppen gesenkt werden.
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The Optimal Cow Size for Intermountain Cow-Calf Operations: The Impact of Public Grazing Fees on the Optimal Cow SizeRussell, Jesse 01 May 2014 (has links)
The cattle industry is very competitive which is forcing cow-calf producers to strive for efficiency. Research has shown that as a cows mature weight increases, feed efficiency decreases, as well as reproductive efficiency and other production factors. The purpose of this paper is to (1) identify the economically optimum cow size when charging for grazing public lands on a true Animal Unit Equivalent (AUE) basis and (2) determine if the current practice of charging on a per head basis for grazing public lands has an effect on the optimal cow size.
To simplify the complexity of this problem, three different resource bases common in the Intermountain West (resource base 1, time grazing = 100%; resource base 2, time grazing = 75%; and resource base 3 time grazing = 50%) were defined, as well as three different weights of cattle (small, medium and large). Grazing plans were created for each resource base and winter rations were balanced to ensure adequate nutrition and accurate budgeting. Linear programming was used to determine an optimal cow size for each resource base when charging on a per head basis and by a true AUE.
When grazing on public land was charged on a true AUE basis, the small cows generated the highest net returns on all resources. Also, each resource base was able to maintain a larger number of the smaller cows than the medium or large cows under these conditions. When grazing on public lands was charge on a per head basis, as is typical, the large cow generated the greatest net returns on resource base 1 and 2. However, the small cow generated the greatest net return on resource base 3. These findings suggest that the current practice of charging for grazing public land on a per head basis does have an impact on cow size.
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Ecology of Coyotes on the Valles Caldera National Preserve, New Mexico: Implications for Elk Calf RecruitmentGifford, Suzanne J. 01 May 2013 (has links)
Valles Caldera National Preserve (VCNP) managers were concerned about low elk recruitment observed at the same time as an apparent increase in sightings of coyotes and observations of coyote predation on elk calves. The goal of this study was to describe coyotes’ ecological interactions with elk, particularly coyote diet and movements on the Valle Grande, a large grassland meadow in the southeastern portion of the VCNP.
We examined coyote diet by quantifying undigested remains of food items in coyote scats (feces). The most frequent taxa were rodents (montane voles and pocket gophers), elk (adult and calf), insects (grasshoppers and beetles), mountain cottontail rabbits, and plants. Most food types varied significantly seasonally and annually, likely due to climatic variation and the relative availability or vulnerability of food items. In particular, an increase in calf elk consumed during summer 2006 followed a dry winter when elk may have been in a lower nutritional state.
We analyzed locations of 33 coyotes, obtained via global positioning system (GPS) collars and radio-tracking. We classified 23 coyotes as residents, living with a social group in a defined area (11.0 km2 mean), and 10 coyotes as transient, with less fidelity to specific areas and often travelling around the edges of the areas occupied by the four resident packs. Coyotes spent most of their time in dry meadow habitat. Coyotes spent more time in riparian habitat than expected based on its availability within home range and less time in forests. We found no relationship between coyote social cohesion (proximity of pack members to each other) and the proportion of elk in coyote diets. We concluded that coyote sociality on VCNP was relatively stable year-round despite changes in biological needs and prey size.
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Essential Tyrosine Residues in Calf Liver Uridine Diphosphoglucose Pyrophosphorylase, E.C. 2.7.7.9.Bachmann, Robert Carl 01 May 1972 (has links)
The catalytic necessity of tyrosine residues in uridine diphospho- glucose pyrophosphorylase [E.C. 2.7.7.9] was investigated. Chemical modification of the pyrophosphorylase by N-acetylimidazole indicated that tyrosine residues were essential for activity. Approximately 23 of 112 tyrosines per molecule of 475,000 Daltons could be 0-acetylated. Solvent perturbation difference spectroscopy supported this number of exposed tyrosine side chains and in conjunction with chemical modification indicated that at least 11 to 12 tyrosyl residues per protein molecule are fully exposed. it her subst rate, uridine t riphosphate or uridine diphosphoglucose, afforded significant protection against inactivation by N-acetylimidazole. The significance of these tyrosine residues is discussed in terms of a quaternary subunit model for uridine diphosphoglucose pyrophosphorylase.
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Analysis of buffalo colostrum and blod serum from bubaline calves with enfasis on passive immunity transfer /Souza, Damazio Campos de. January 2019 (has links)
Orientador: José Jurandir Fagliari / Resumo: O objetivo deste estudo foi avaliar a transferência de imunidade passiva em bezerros bubalinos saudáveis e avaliar a influência das concentrações séricas de imunoglobulina G (IgG) às 24 horas no desempenho produtivo nos primeiros 90 dias de idade dos bezerros. Amostras de colostro de novilhas (sem parto prévio), primíparas e pluríparas; e amostras de sangue de seus respectivos bezerros foram coletadas no nascimento, antes da ingestão de colostro, e 24h, 48h e 72h após o nascimento para determinação das atividades séricas de gamamaglutamiltransferase (GGT) e fosfatase alcalina (ALP); e concentrações séricas de proteína total (PT), imunoglobulinas A (IgA) e G (IgG) e lactoferrina. As concentrações de imunoglobulinas de amostras de colostro de búfalas e amostras de sangue de bezerros foram determinadas pela técnica de eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE). O peso foi medido a cada semana após o nascimento até os três meses de idade. Os resultados da transferência de imunidade passiva foram analisados como medidas repetidas no tempo e o peso e o ganho de peso diário (GPD) foram avaliados por regressão linear simples. As diferenças foram consideradas significativas quando P ≤ 0,05. Os búfalos nasceram hipogamaglobulinêmicos (4,23±0,33 mg/mL), e às 24 horas as concentrações séricas de IgG foram de 34,5±1,48 mg/mL, a transferência de imunidade passiva foi considerada bem-sucedida. As concentrações séricas de PT são recomendadas como parâm... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the passive immunity transfer on healthy buffalo calves and evaluate the influence of serum concentrations of immunoglobulin G (IgG) at 24hs on productive performance on the first 90 days of age of Murrah buffalo calves. Colostrum samples from heifers (without previous calving), primiparous and pluriparous dams; and blood samples from their respective calves, were taken at birth, before colostrum ingestion, and at 24h, 48h, and 72h after birth for determination of serum activities of gamma-glutamyltransferase (GGT) and alkaline phosphatase (ALP); and serum concentrations of total protein (TP), immunoglobulins A (IgA) and G (IgG) and lactoferrin. The concentrations of immunoglobulins of colostrum samples from buffaloes and blood samples from calves were determined by sodium dodecyl sulfate-containing polyacrylamide gel electrophoresis (SDS-PAGE) technique. Weight was measured following each week after birth until three months of age. The passive immunity transfer results were analyzed as repeated measures and weight and average daily gain (ADG) were evaluated by simple linear regression. Differences were considered significant when P≤0.05. As buffalo calves were born hypogammaglobulinemic (4.23±0.33 mg/mL), and at 24h serum concentrations of IgG were of 34.5±1.48 mg/mL, passive immunity transfer was successful. Serum concentrations of TP at 24h is recommended as reliable indirect parameter to evaluate passive immunity transfer on buffalo c... (Complete abstract click electronic access below) / Doutor
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Bovine Kryptosporidiose: Analyse einer integrierten Bekämpfungsmassnahme unter den Bedingungen einer natürlichen Infektionsexposition in einem KälberbestandErbe, Susanne 21 September 2010 (has links)
Die Kryptosporidiose des Kalbes stellt eine orale Infektion mit dem obligat pathogenen Erreger Cryptosporidium parvum dar. Sie verursacht hauptsächlich bei Jungtieren unterschiedlich schwere und zuweilen tödlich verlaufende Diarrhoe. Zur Analyse einer integrierten Bekämpfungsmaßnahme unter den Bedingungen einer natürlichen Infektionsexposition wurden 123 Kälber eines landwirtschaftlichen Nutzbetriebes in Thüringen untersucht. Die Tiere wurden in zwei Gruppen randomisiert nach ihrem Geburtstermin aufgeteilt. Der Gruppe H+ waren 62 Tiere zugehörig welche in den ersten sieben Lebenstagen Halofuginon in einer Dosis von 120 µg/kg KGW oral verabreicht bekamen und in Neopredisan® desinfizierten Buchten aufgestallt wurden. Gruppe H- stellte mit 61 Kälbern die unbehandelte Kontrolle dar, deren Buchten ausschließlich mittels Hochdruckreinigung gesäubert wurden. Alle Tiere wurden in den ersten vier Lebenswochen gewogen beginnend am ersten Lebenstag. In der 25. Lebenswoche fand eine zusätzliche Gewichtsbestimmung statt wobei die Tiere der H+ Gruppe im Mittel um 5,8 kg (p>0,05) schwerer waren als H- Tiere. Die Kälber beider Gruppen wurden in den ersten vier Lebenswochen jeden dritten Lebenstag hinsichtlich der Oozystenausscheidung, des Ernährungszustandes, des Trinkverhaltens, des Dehydratationsgrades und der Körpertemperatur untersucht. Zusätzlich wurde die Lunge auskultiert und die Konsistenz der Kotproben beurteilt. Durch die Halofuginonbehandlung und der zusätzlichen Desinfektion fand in der H+ Gruppe eine signifikante Senkung der Oozystenausscheidung bis zum 10. Lebenstag statt, jedoch waren die Tiere nach Absetzen der Behandlung für eine Infektion voll empfänglich. Das Auftreten von Diarrhoe zeigte eine positive Korrelation zur Oozystenanzahl untersuchter Kotproben. Die Anzahl an Tagen mit Durchfall korrelierte positiv und signifikant mit der Oozystenausscheidung. Für den Ernährungszustand, das Trinkverhalten, der Körpertemperatur sowie weitere klinischer Parameter bestand zu keiner Zeit eine signifikante Beziehung zur Kryptosporidiose. Damit erwies sich die integrierte Bekämpfung aus Halofuginonbehandlung und gezielter Desinfektion im für die Kälber kritischen Zeitraum der ersten zwei Lebenswochen als überaus effektiv. Allerdings muß bei derart geschützten Kälbern anschließend aufgrund einer offensichtlich nicht ausreichenden Immunisierung mit einer höheren Empfänglichkeit für C. parvum gerechnet werden.
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Effect of rotation frequency and stocking rate on herbage quality and animal performance of cow-calf pairs raised on permanent pasture in QuebecBergeron, Michel, 1967- January 2000 (has links)
No description available.
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