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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

Economic Consequences Associated with Johne’s Disease in Cow-Calf Operations

Bhattarai, Bikash 16 December 2013 (has links)
Johne’s disease (JD) in cattle is a disease of economic importance caused by Mycobacterium avium subspecies paratuberculosis (MAP). Studies were conducted to estimate the losses due to lower weaning weight of beef calves from MAP test-positive dams, to compare the perceptions of producers and veterinarians on the burden and economic aspects of MAP infection in cow-calf herds, and to evaluate whether testing and culling MAP test-positive cows is economically beneficial. Calves from cows with strong-positive ELISA results were 21.5 kg lighter at weaning compared to calves from ELISA-negative cows. Calves from heavy MAP shedding cows were 58.5 kg lighter, and calves from moderate shedders were 40.8 kg lighter compared to the calves from fecal-culture negative cows. Based on average feeder calf value during 2007 to 2012, these losses corresponded to US $57 per calf for ELISA strong-positive dams, US $157 per calf for heavy fecal shedder dams, and US $109 per calf for a moderate fecal shedder dam. Seedstock producers and the producers enrolled in control programs were more likely to have MAP uninfected herds. The average prevalence reported by producers was 0.8%. Compared to the small herds (<50 head), the average test-positive percentages and estimated prevalences were reported to be higher in medium (50-149) and highest in large (≥150) herds. Veterinarians reported an overall animal level prevalence in their client herds of 5%. Seedstock herds had a lower prevalence and these producers were more likely to enroll in a JD control program. Income lost due to the presence of JD in an infected cattle herd was perceived to be higher by veterinarians. Compared to the veterinarians, seedstock producers were more likely to perceive genetic losses due to culling MAP positive cows. Average annual loss due to JD in a 100 cow herd with a 7% MAP prevalence was $1,644 and $1,747 based on information provided by producers and veterinarians, respectively. Herd level production decreased with increasing prevalence. Compared to test and cull after ELISA or ELISA followed by fecal culture, using fecal culture alone provided the fastest reduction in herd prevalence. Fecal culture was also the least costly alternative based on long-term cumulative costs of an annual test and cull program. Results from the current study suggest that although testing provides faster progress, limiting within herd transmission by sale of all weaned calves and purchasing only low-risk replacements can also reduce prevalence. Results suggest that MAP infection in cows causes significant losses for the calves that are produced. While the knowledge about JD varied between producers and veterinarians, seedstock producers were more enthusiastic about MAP control programs and had lower MAP prevalence in their herds. Overall losses due to MAP infection in the herd might be substantial. It is very costly to control or eliminate MAP once the infection is established in a herd.
42

Foot Strike in Runners: The Relationship Between Heel Length, Foot Strike, and Calf Muscle Thickness

Wessbecher, Laura 01 January 2015 (has links)
One major way that running style varies between individuals is how their foot strikes the ground (forefoot strike or rearfoot strike). Running generates a torque about the ankle that depends on the individual’s foot strike pattern, length of their plantar flexor moment arm, and force generated from the plantar flexor muscles. The foot strike pattern during running, gastrocnemii muscle thickness, and heel length (used as an approximation for plantar flexor moment arm) were determined in 41 runners. Forefoot and rearfoot strike runners had the same thickness of the gastrocnemii muscles. However, in comparison with sedentary walkers, the runners had thicker calf muscles. These results imply a “peak” muscle thickness seems to be attained by running. Runners with longer heels were more likely to use a forefoot strike running style, possibly due to a mechanical advantage in the generation of torque.
43

Studien zur Behandlung der Eimeria bovis - Kokzidiose des Kalbes mit Toltrazuril

Uebe, Friederike 24 November 2011 (has links) (PDF)
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.
44

BIOELECTRICAL IMPEDANCE ANALYSIS OF MUSCLE FUNCTION AND ACTIVITY: (BIODYNAMIC ANALYSIS)

William Mccullagh Unknown Date (has links)
Abstract There is a need in medicine and research for noninvasive, painless, safe and simple bed-side techniques to measure physiological processes associated with muscle function and activity. Bioelectrical Impedance Analysis (BIA) is a widely used, noninvasive, painless, safe and simple procedure for the measurement of body composition. However, although capable of producing accurate and reproducible data, it is known to be prone to movement artifacts. This poses the interesting question “Could impedance changes be used to monitor movement and, consequently, be related to muscle function or activity?” This project investigated the utility of impedance change as a monitoring technique for physiological processes that involve movement such as muscular contraction, the calf muscle pump, and swallowing. The impedance of leg muscle segments during locomotion, whilst riding a stationary exercise cycle, was measured at discrete frequencies and by bioimpedance spectroscopy to monitor muscle function or activity. Impedance traces were compared to information obtained by electromyography (EMG). Impedance, at a discrete frequency, was able to measure the cadence of cycling and its magnitude was related to the position of the pedal during the pedal cycle. When the cycling action was measured by bioimpedance spectroscopy, R0 and Zc showed a statistically significant difference, (p<0.05), between all angles of the pedal crank cycle while R∞ showed a statistically significant difference between angles in the lower hemisphere of the pedal crank cycle. The cyclical changes in impedance during cycling may be attributed to changes in shape and volume of the muscle during contraction as well as a volume change due to blood and lymph being pumped from the limb by the action of the calf muscle pump. Based on procedures used in the cycling studies, an impedance-based method for the measurement of calf muscle pump function during an exercise protocol, originally designed for use with air plethysmography, was developed. It was shown that impedance measured at 5 kHz provides a simple, non-invasive method for the measurement of the ejection fraction and ejection volume of the calf muscle pump as well as other haemodynamic variables. The impedance-based method was less technically challenging than accepted volumetric methods, such as air plethysmography and strain gauge plethysmography, and non-invasive c.f. ambulatory venous pressure, enabling it to be used repeatedly. Muscle function and activity is not confined to the legs so impedance changes in the arm and forearm during exercise were measured. Impedance measurements, at discrete frequencies and using bioimpedance spectroscopy, of the forearm during contractions of the hand were able to distinguish the difference between a ramp and a pulse contraction. When the impedance of the arm and forearm were plotted against the angle of the forearm to the horizontal during a bicep curl, there was an hysteresis effect. Impedance traces of a bicep curl were compared to an EMG trace of the same action. The larynx is a hollow muscular organ situated in the front of the neck above the trachea consisting of a framework of cartilages bound together by muscles and ligaments. The two major functions of the larynx are deglutition and phonation. Dysphagia, which is becoming more prevalent as the population ages, is defined as difficulty in swallowing thin liquids such as water or juices which splash into the trachea because the patient is unable to control the thin liquid bolus. Aspiration pneumonia and dehydration can be prevented by using thickened liquids which allow patients to achieve a safer swallowing response, but it is difficult to assess this response without interfering with the swallowing process. Impedance pharynography (IPG) is a technique using BIA to monitor an impedance waveform of the swallowing process that presents no radiation hazard to the patient, is non-invasive and does not require specialist trained personnel to operate it. Resistance changes across the neck were measured while subjects swallowed solutions of different viscosities. The resistance changes were distinctive and reproducible for each of the solutions of different viscosities which were swallowed. Measuring the function of the larynx by this method could be useful in the diagnosis and treatment of dysphagia. In conclusion, the studies described in this thesis demonstrate the potential usefulness of the measurement of change in impedance as a measure of muscle activity. Impedance-based methods can measure volume changes associated with changes in cross-sectional area of the muscles involved in contraction as well as compartmental fluid changes caused by the force of the contraction on the surrounding tissues including the vasculature. In particular, measuring the ejection fraction and other haemodynamic variables of the calf muscle pump by impedance has the potential to become the method of choice in the future because it is easy to use, inexpensive, non-invasive, safe, and hygenic. Measuring resistance changes across the neck during swallowing yields distinctive waveforms with features corresponding to the physiological phases of the swallowing process as well as identifying distinctive swallowing patterns associated with the different viscosities of liquids swallowed. Function of the larynx and the associated diseases of the larynx will potentially be easier to diagnose and treat with a safe, non-invasive, inexpensive, portable bed-side method of assessment such as BIA.
45

BIOELECTRICAL IMPEDANCE ANALYSIS OF MUSCLE FUNCTION AND ACTIVITY: (BIODYNAMIC ANALYSIS)

William Mccullagh Unknown Date (has links)
Abstract There is a need in medicine and research for noninvasive, painless, safe and simple bed-side techniques to measure physiological processes associated with muscle function and activity. Bioelectrical Impedance Analysis (BIA) is a widely used, noninvasive, painless, safe and simple procedure for the measurement of body composition. However, although capable of producing accurate and reproducible data, it is known to be prone to movement artifacts. This poses the interesting question “Could impedance changes be used to monitor movement and, consequently, be related to muscle function or activity?” This project investigated the utility of impedance change as a monitoring technique for physiological processes that involve movement such as muscular contraction, the calf muscle pump, and swallowing. The impedance of leg muscle segments during locomotion, whilst riding a stationary exercise cycle, was measured at discrete frequencies and by bioimpedance spectroscopy to monitor muscle function or activity. Impedance traces were compared to information obtained by electromyography (EMG). Impedance, at a discrete frequency, was able to measure the cadence of cycling and its magnitude was related to the position of the pedal during the pedal cycle. When the cycling action was measured by bioimpedance spectroscopy, R0 and Zc showed a statistically significant difference, (p<0.05), between all angles of the pedal crank cycle while R∞ showed a statistically significant difference between angles in the lower hemisphere of the pedal crank cycle. The cyclical changes in impedance during cycling may be attributed to changes in shape and volume of the muscle during contraction as well as a volume change due to blood and lymph being pumped from the limb by the action of the calf muscle pump. Based on procedures used in the cycling studies, an impedance-based method for the measurement of calf muscle pump function during an exercise protocol, originally designed for use with air plethysmography, was developed. It was shown that impedance measured at 5 kHz provides a simple, non-invasive method for the measurement of the ejection fraction and ejection volume of the calf muscle pump as well as other haemodynamic variables. The impedance-based method was less technically challenging than accepted volumetric methods, such as air plethysmography and strain gauge plethysmography, and non-invasive c.f. ambulatory venous pressure, enabling it to be used repeatedly. Muscle function and activity is not confined to the legs so impedance changes in the arm and forearm during exercise were measured. Impedance measurements, at discrete frequencies and using bioimpedance spectroscopy, of the forearm during contractions of the hand were able to distinguish the difference between a ramp and a pulse contraction. When the impedance of the arm and forearm were plotted against the angle of the forearm to the horizontal during a bicep curl, there was an hysteresis effect. Impedance traces of a bicep curl were compared to an EMG trace of the same action. The larynx is a hollow muscular organ situated in the front of the neck above the trachea consisting of a framework of cartilages bound together by muscles and ligaments. The two major functions of the larynx are deglutition and phonation. Dysphagia, which is becoming more prevalent as the population ages, is defined as difficulty in swallowing thin liquids such as water or juices which splash into the trachea because the patient is unable to control the thin liquid bolus. Aspiration pneumonia and dehydration can be prevented by using thickened liquids which allow patients to achieve a safer swallowing response, but it is difficult to assess this response without interfering with the swallowing process. Impedance pharynography (IPG) is a technique using BIA to monitor an impedance waveform of the swallowing process that presents no radiation hazard to the patient, is non-invasive and does not require specialist trained personnel to operate it. Resistance changes across the neck were measured while subjects swallowed solutions of different viscosities. The resistance changes were distinctive and reproducible for each of the solutions of different viscosities which were swallowed. Measuring the function of the larynx by this method could be useful in the diagnosis and treatment of dysphagia. In conclusion, the studies described in this thesis demonstrate the potential usefulness of the measurement of change in impedance as a measure of muscle activity. Impedance-based methods can measure volume changes associated with changes in cross-sectional area of the muscles involved in contraction as well as compartmental fluid changes caused by the force of the contraction on the surrounding tissues including the vasculature. In particular, measuring the ejection fraction and other haemodynamic variables of the calf muscle pump by impedance has the potential to become the method of choice in the future because it is easy to use, inexpensive, non-invasive, safe, and hygenic. Measuring resistance changes across the neck during swallowing yields distinctive waveforms with features corresponding to the physiological phases of the swallowing process as well as identifying distinctive swallowing patterns associated with the different viscosities of liquids swallowed. Function of the larynx and the associated diseases of the larynx will potentially be easier to diagnose and treat with a safe, non-invasive, inexpensive, portable bed-side method of assessment such as BIA.
46

BIOELECTRICAL IMPEDANCE ANALYSIS OF MUSCLE FUNCTION AND ACTIVITY: (BIODYNAMIC ANALYSIS)

William Mccullagh Unknown Date (has links)
Abstract There is a need in medicine and research for noninvasive, painless, safe and simple bed-side techniques to measure physiological processes associated with muscle function and activity. Bioelectrical Impedance Analysis (BIA) is a widely used, noninvasive, painless, safe and simple procedure for the measurement of body composition. However, although capable of producing accurate and reproducible data, it is known to be prone to movement artifacts. This poses the interesting question “Could impedance changes be used to monitor movement and, consequently, be related to muscle function or activity?” This project investigated the utility of impedance change as a monitoring technique for physiological processes that involve movement such as muscular contraction, the calf muscle pump, and swallowing. The impedance of leg muscle segments during locomotion, whilst riding a stationary exercise cycle, was measured at discrete frequencies and by bioimpedance spectroscopy to monitor muscle function or activity. Impedance traces were compared to information obtained by electromyography (EMG). Impedance, at a discrete frequency, was able to measure the cadence of cycling and its magnitude was related to the position of the pedal during the pedal cycle. When the cycling action was measured by bioimpedance spectroscopy, R0 and Zc showed a statistically significant difference, (p<0.05), between all angles of the pedal crank cycle while R∞ showed a statistically significant difference between angles in the lower hemisphere of the pedal crank cycle. The cyclical changes in impedance during cycling may be attributed to changes in shape and volume of the muscle during contraction as well as a volume change due to blood and lymph being pumped from the limb by the action of the calf muscle pump. Based on procedures used in the cycling studies, an impedance-based method for the measurement of calf muscle pump function during an exercise protocol, originally designed for use with air plethysmography, was developed. It was shown that impedance measured at 5 kHz provides a simple, non-invasive method for the measurement of the ejection fraction and ejection volume of the calf muscle pump as well as other haemodynamic variables. The impedance-based method was less technically challenging than accepted volumetric methods, such as air plethysmography and strain gauge plethysmography, and non-invasive c.f. ambulatory venous pressure, enabling it to be used repeatedly. Muscle function and activity is not confined to the legs so impedance changes in the arm and forearm during exercise were measured. Impedance measurements, at discrete frequencies and using bioimpedance spectroscopy, of the forearm during contractions of the hand were able to distinguish the difference between a ramp and a pulse contraction. When the impedance of the arm and forearm were plotted against the angle of the forearm to the horizontal during a bicep curl, there was an hysteresis effect. Impedance traces of a bicep curl were compared to an EMG trace of the same action. The larynx is a hollow muscular organ situated in the front of the neck above the trachea consisting of a framework of cartilages bound together by muscles and ligaments. The two major functions of the larynx are deglutition and phonation. Dysphagia, which is becoming more prevalent as the population ages, is defined as difficulty in swallowing thin liquids such as water or juices which splash into the trachea because the patient is unable to control the thin liquid bolus. Aspiration pneumonia and dehydration can be prevented by using thickened liquids which allow patients to achieve a safer swallowing response, but it is difficult to assess this response without interfering with the swallowing process. Impedance pharynography (IPG) is a technique using BIA to monitor an impedance waveform of the swallowing process that presents no radiation hazard to the patient, is non-invasive and does not require specialist trained personnel to operate it. Resistance changes across the neck were measured while subjects swallowed solutions of different viscosities. The resistance changes were distinctive and reproducible for each of the solutions of different viscosities which were swallowed. Measuring the function of the larynx by this method could be useful in the diagnosis and treatment of dysphagia. In conclusion, the studies described in this thesis demonstrate the potential usefulness of the measurement of change in impedance as a measure of muscle activity. Impedance-based methods can measure volume changes associated with changes in cross-sectional area of the muscles involved in contraction as well as compartmental fluid changes caused by the force of the contraction on the surrounding tissues including the vasculature. In particular, measuring the ejection fraction and other haemodynamic variables of the calf muscle pump by impedance has the potential to become the method of choice in the future because it is easy to use, inexpensive, non-invasive, safe, and hygenic. Measuring resistance changes across the neck during swallowing yields distinctive waveforms with features corresponding to the physiological phases of the swallowing process as well as identifying distinctive swallowing patterns associated with the different viscosities of liquids swallowed. Function of the larynx and the associated diseases of the larynx will potentially be easier to diagnose and treat with a safe, non-invasive, inexpensive, portable bed-side method of assessment such as BIA.
47

Vliv kvality mleziva na růst a zdravotní stav telat

RAJTROVÁ, Aneta January 2018 (has links)
The thesis summarizes the importance of the quality of colostrum, its composition and impact on the growth and state of health of calves. Colostrum includes important substances necessary for the health of a calf. The value of overall protein in which the amount of immunoglobulins is reflected is a key indicator. It is important for the health of the calf that it receives sufficient amount of quality colostrum in time, gaining immunoglobulins necessary for the first weeks of life. Significant aspects include the quality of colostrum that we provide a calf with, the amount of colostrum consumed, technology, consistency and personnel responsibility, which reflect retrospectively during the inspection of colostrum nutrition of calves that can be carried out by several methods mentioned further. These aspects influence the state of health of calves, growth and many more indicators in the production that follows. In the work, I concentrated on these very aspects, the extent to which they interact as well as on the state of health of calves. The data that I was provided with by Ing. Barbora Šitnerová (principal livestock specialist of Agraspol Předmíř a.s.) was processed into tables and graphs from which statistically important results were learnt.
48

Desempenho de bezerros leiteiros recebendo probiótico contendo Bacillus subtilis e Bacillus licheniformis / Performance of calves receiving probiotic containing Bacillus subtilis and Bacillus licheniformis

Thais Manzoni Torrezan 18 April 2016 (has links)
O objetivo deste estudo foi avaliar a suplementação de um probiótico composto por cepas de Bacillus subtilis e Bacillus licheniformis, fornecidos via sucedâneo lácteo, no que se refere ao escore e pH fecal, contagem de microrganismos intestinais, parâmetros sanguíneos e desempenho geral dos animais. Foram utilizados 24 animais da raça Holandês que receberam 4L/dia de sucedâneo comercial (15PB:15EE), além de livre acesso a água e concentrado inicial. O desaleitamento ocorreu na 8ª semana de vida. Os animais foram distribuídos em delineamento de blocos casualizados, em dois tratamentos: 1) Controle - sem a suplementação de probiótico; 2) Suplementação de 2g/d (1,6 x 109 UFC) de Bacillus subtilis e Bacillus licheniformis via sucedâneo lácteo. Semanalmente foram realizadas pesagens e aferições de medidas corporais (altura de cernelha, perímetro torácico e largura de garupa); e colheitas de sangue para determinação de glicose, proteína total, ureia e albumina, além de determinação de hematócrito. Foram colhidas amostras semanalmente para contagem de bactérias ácido láticas e enterobactérias e determinação de pH fecal. O monitoramento do consumo de concentrado e do escore fecal foi realizado diariamente. O peso corporal, o ganho de peso médio diário e as medidas corporais não foram alteradas (P>0,05) pela suplementação do probiótico contendo Bacillus subtilis e Bacillus licheniformis; muito embora tenham apresentado efeito significativo de idade dos animais (P<0,001). O escore fecal, pH fecal e consumo de concentrado diário também não foram afetados pela suplementação com probiótico. No entanto, o consumo de concentrado e o pH fecal sofreram influência da idade em resposta ao crescimento natural dos bezerros. A contagem de bactérias ácido láticas foi maior que número de enterobactérias durante todo o período (P<0,05). Apenas as enterobactérias sofreram efeito da idade (P<0,05), enquanto as bactérias ácido láticas permaneceram variando, porém dentro de um padrão constante. Os parâmetros sanguíneos também não foram afetados pela suplementação com probiótico (P>0,05) mas todos, com a exceção da albumina, tiveram influência da idade (P<0,001). A suplementação com o probiótico contendo Bacillus subtilis e Bacillus licheniformis via sucedâneo não apresentou benefícios no desempenho ou no metabolismo de bezerros leiteiros, bem como não reduziu a ocorrência de casos de diarreia. / The objective of this study was to evaluate the supplementation of a probiotic containing strains of Bacillus subtilis and Bacillus licheniformis, supplied via milk replacer, with regard to fecal score and pH, intestinal microorganisms count, blood parameters and overall performance of the animals. Twenty-four Holstein calves were utilized and received 4L/d of liquid diet consisting of commercial milk replacer (20CP:15EE), and had free access to water and starter concentrate. Weaning occurred at the 8th week of age. Animals were distributed in a randomized block design, in the following treatments: 1) Control - without supplementation with probiotic, 2) Supplementation: 2g/d of Bacillus subtilis and Bacillus licheniformis (1.6 x 109 CFU), via milk replacer. Every week calves were weighted and body measurements were taken (hip width, withers height and heart girth). Blood samples were drawn weekly for determination of hematocrit, glucose, total protein, urea and albumin. Fecal samples were weekly collected for lactic acid bacteria and enterobacteria couting and fecal pH determination. Concentrate starter intake and fecal scores were monitored daily. Body weight, average daily gain, and corporal measurements were not affected (P>0,05) by the supplementation of probiotic; however, presented a significant age effect (P<0,001). The fecal score, fecal pH and starter intake were not affected by probiotic supplementation (P>0.05). However, starter intake and fecal pH were affected by age due to calves\' natural growth. The acid lactic bacteria count was higher than the count of enterobacteria during the whole evaluation period. Only enterobacteria were affected by the age of animals, while acid lactic bacteria remained constant despite little variations. Blood parameters were also not affect by supplementation of probiotic (P>0.05), but all of them, except albumin concentrations, were influenced by age (P<0,001). The supplementation with probiotic containing Bacillus subtilis and Bacillus licheniformis via milk replacer presented no benefits in dairy calves performance or metabolism and did not reduced the occurrence of diarrhea.
49

Parâmetros ecodopplercardiográficos de bezerros da raça Nelore originados através de transferência nuclear de células somáticas adultas - Clonagem / Echodopplercardiographic parameters in Nelore calves produced by adult somatic cell nuclear transfer - Cloning

Fabio Celidonio Pogliani 16 April 2010 (has links)
A presente pesquisa avaliou as anomalias e/ou disfunções cardíacas através da determinação e comparação dos parâmetros ecocardiográficos e ecodopplercardiográficos do fluxo da valva pulmonar em bezerros da raça Nelore originados através de transferência nuclear de células somáticas adultas (TNCS) e concebidos por inseminação artificial ou monta natural durante os primeiros 30 dias de vida, com a finalidade de contribuir nos estudos na área de clonagem e no desenvolvimento da clínica de neonatos bovinos. O delineamento experimental envolveu a avaliação ecocardiográfica do coração e avaliação do fluxo da valva pulmonar através de ecocardiografia Doppler distribuídos nos seguintes intervalos: de 0 a 12 horas após o nascimento, de 12 a 24 horas após o nascimento, de 1 a 2 dias de vida, de 2 a 4 dias de vida, de 4 a 7 dias de vida, de 7 a 10 dias de vida, de 10 a 15 dias de vida, de 15 a 20 dias de vida e de 20 a 30 dias de vida. Os bezerros foram divididos em 2 grupos experimentais: 1- Grupo Controle composto por 10 bezerros obtidos por monta natural ou inseminação artificial e 2- Grupo Clones composto por 10 bezerros obtidos por meio de TNCS. Os parâmetros e índices ecocardiográficos foram: diâmetro interno do átrio esquerdo e direito em sístole, diâmetro interno de ventrículo direito em sístole e diástole, espessura do septo interventricular em sístole e diástole, diâmetro interno do ventrículo esquerdo em sístole e diástole, parede livre do ventrículo esquerdo em sístole e diástole, diâmetro da aorta em diástole, razão átrio esquerdo em sístole e aorta, tempo de ejeção do ventrículo esquerdo, separação septal do ponto E, encurtamento fracional, fração de ejeção, volumes sistólico, diastólico e de ejeção, débito cardíaco, razão septo interventricular em sístole pela parede livre do ventrículo esquerdo em sístole.A avaliação do fluxo da valva pulmonar foi feita através da mensuração da velocidade máxima, velocidade média, tempo de ejeção, tempo de aceleração, integral de velocidade, volume sistólico, débito cardíaco e frequência cardíaca. Dos 10 animais clonados, 3 morreram em até 48 horas de vida apresentando hipertrofia ventricular congênita concêntrica, comunicação interatrial por não oclusão do forame oval e hipertensão arterial pulmonar. Os clones vivos apresentaram fluxo colorido através de comunicação interatrial em até 10 dias de vida enquanto que os bezerros do grupo Controle apresentaram fluxo colorido em até 7 dias. O peso vivo dos animais apresentou alta correlação com o perímetro torácico. Os valores do ecocardiograma determinados para o grupo Controle não são indicados para serem usados como valores de referência para os clones, pois variam muito com o peso dos animais e os clones apresentam variação de peso acima do normal para a espécie. / The present research evaluated anomalies and/or cardiac dysfunctions through the determination and comparison of echocardiographic and echodopplercardiographic parameters of pulmonary valve flow on Nelore breed calves originated from the somatic cell nuclear transfer technique (SCNTT) and from form Nelore breed calves conceived trough artificial insemination or natural mating on its first 30 days of life, with the purpose of contributing on researches on the cloning technique field and on the bovine neonatal clinic development. The experimental design involved heart echocadiographic evaluation and the pulmanary valve echodopplercardiographic evaluation on the following intervals: 0 to 12 hours after birth, 12 to 24 hours after birth, 1 to 2 days old, 2 to 4 days old, 4 to 7 days old, 7 to 10 days old, 10 to 15 days old, 15 to 20 days old and 20 to 30 days old. Calves were allocated in two experimental groups: 1- Control Group composed of 10 calves conceived through artificial insemination and natural mating and 2- Clone Group composed of 10 calves originated from SCNTT. The echocardiographic parameters and indices were: systolic left and right atrium diameters, systolic and diastolic internal diameter, interventricle septum thickness during the systolic and diastolic movement, systolic and diastolic left ventricle internal diameter, left ventricle free wall during systolic and diastolic movement, diastolic aorta diameter, systolic left atrium and aortic root ratio, left ventricle ejection timing, E-point septal separation, fractional shortening, ejection fraction, systolic volume, diastolic volume, ejection volume, systolic interventricle septum and systolic left ventricle ratio. The pulmonary valve flow evaluation was performed through the measurement of the maximum velocity, the average velocity, ejection time, acceleration time, velocity integral, systolic volume, cardiac debit and cardiac frequency. 3 from 10 clones died up to 48 hours after birth, presented congenital concentric ventricle hipertrophy, interatrial communication due to non occlusive oval foramen and pulmonary artery hypertension. The living clones presented colored flow through the interatrial communication until 10 days old while animals from Control Group presented it until 7 days old. Animals´ body weight and thoracic perimeter showed high correlation. The echocardiographic values determined for Control Group are not supposed to be used as reference for clones, because body weight causes great variation on these values and clones present much bigger body weight than what is normal for the species.
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Effects of Early Weaning Calves as a Management Tool

Lowe, Victoria H., Lowe, Victoria H. January 2017 (has links)
The goal of a cow-calf producer is to produce a calf each year per cow. Research suggests that first year heifers struggle breeding back with their second calf because of the adjustments to new range/main herd conditions and the partitioning of nutrients between gaining weight, milk production, and gestation. This study was conducted at the V-V ranch at the University of Arizona for five years and looked at the effects on young cows when calves were weaned from first year heifers at 80 days rather than 205 days. Early weaning allows for gestational benefits because they are given the opportunity to adapt to herd conditions by applying feed resources to the in utero fetus and their own body condition rather than lactation. All first year heifers were included over three years, and were randomly assigned to two groups, normal weaning (NW) or early weaning (EW). This resulted in 122 heifers in the group whose calves were EW and 119 heifers in the group whose calves were NW. Heifers that were in the EW group bred back at a 27% higher rate in their second year, and had 15% greater longevity in the herd. Calves that were in utero when the nursing calves were early weaned were 16.4 kg heavier at weaning. Part of this was due to the age of the calf and part to gestational health. Early weaning was an effective strategy for improving reproductive performance of first year heifers as well as their survival rate in the herd to 5 years of age. It also resulted in improved performance for their in utero calves.

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