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.

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.

Objetivou-se por meio deste trabalho identificar a existência de expressões faciais e corporais que refletem o estado emocional de bezerros de raças leiteiras. Foram estudados 32 bezerros com idades entre 1 e 8 semanas durante quatro dias. Foram formados 8 grupos com 4 animais cada, de forma aleatória, formando grupos homogêneos entre si em idade. Cada grupo foi analisado duas vezes. Os animais foram levados a uma câmara de teste com laterais abertas e coberta com telha metálica, sobre uma área de pastagem, onde receberam a aplicação dos tratamentos \"estímulo positivo afago\" e \"estímulo negativo teste do guarda-chuva\". A expressão facial foi analisada por meio das unidades de ação facial sobrancelha, boca, narina e área da esclera ocular. A expressão corporal foi verificada por meio das variáveis posição de orelha e posição de cauda. Os animais foram avaliados durante seis tempos experimentais: ambiente natural, pré-teste, teste, pós-teste 1, pós-teste 2 e ambiente natural após teste. Ambos os estímulos provocaram redução (p < 0,05) da área de esclera ocular de 3,50 cm2 para 1,10 cm2, e da área de narina de 8,58 cm2 para 6,07 cm2. A sobrancelha levantada esteve presente durante o estímulo negativo (p > 0,05). Não foi possível identificar se as modificações nas unidades de ação facial foram decorrentes de emoções positivas ou negativas. Toda manipulação com os animais provocou alteração nas unidades faciais. O posicionamento de orelha e cauda estão relacionados a emoções positivas e negativas. A posição de orelha \"para atrás\" e a posição de cauda \"arqueada\" estão associadas a expressão de emoções positivas. A posição de orelha \"horizontal\" e a posição de cauda \"presa\", a emoções negativas. Os tipos de posições de orelha e cauda são indicadores de estado emocional positivo ou negativo em bezerros, e há um grande potencial para o uso dessas medidas para mensurá-lo. Assim, identificamos a existência de expressões faciais, com a variável sobrancelha, e corporais, com a posição de orelha \"para atrás\" e cauda \"arqueada\" que refletem estados emocionais positivos; e posição de orelha \"horizontal\" e cauda \"presa\" que refletem estados emocionais negativos em bezerros. / The purpose of this research was to identify the existence of facial and body expressions that reflects the emotional state of dairy calves. Thirty-two calves between 1 and 8 weeks of age were studied for four consecutive days. Eight groups with four animals each were formed randomly, forming homogeneous groups among themselves in age. Each group was analyzed twice. The animals were taken to a test chamber with open sides and covered with metal tile over a pasture area, where they received the application of the treatments positive \"neck stroking\" and negative \"umbrella test\" (Sandem et al. 2004). The facial expression was analyzed through the facial action units: eyebrow, mouth, nostril and eye white. Body expression was verified by the ear position and tail position variables. The animals were evaluated during six experimental times: natural environment, pre-test, test, post-test 1, post-test 2 and natural environment after the test. Both stimuli caused reduction (p < 0,05) in eye white area from 3,50 cm2 to 1,10 cm2, and area of nostril from 8,58 cm2 to 6,07 cm2. The raised eyebrow was present during the negative stimulus. It was not possible to identify if the changes in facial action units were due to positive or negative emotions. All manipulation with the animals caused a change in the facial units. The positioning of ear and tail are related to positive and negative emotions. The \"back\" ear position and the \"arched\" tail position are associated with expressing positive emotions. The \"horizontal\" ear position and the \"between hindlimbs\" tail position, to negative emotions. The types of ear and tail positions are indicators of positive or negative emotional state in calves, and there is great potential for using these measures to evaluate emotions. Thus, we identified the existence of facial expressions, with the variable eyebrow, and body expression, with the position of \"back\" ear and \"arched\" tail that reflects positive emotional states; and \"horizontal\" ear position and \"between hindlimbs\" tail reflecting negative emotional states in calves.

The operating costs for farms and ranches in the United States have increased 81 percent between 1970 and 1976. Calf prices over this same period have fluctuated dramatically and have fallen from a high of $58/cwt in 1973 to a low of $2 6/ cwt in 1975. Since 1973, the increasing operating costs have exceeded the returns gene rated by the low calf prices and have left operators in a negative financial position. This case study has shown that the operator has increased both the scale and efficiency of his operation through improved lives tock husbandry and range improvements , yet has been unable to keep up with the increase in operating costs. A res t rot at ion grazing system and associated range improvements were implemented in 1970 on the summer mountain range. The resultant increase in forage prod uction allowed a 45 percent increase in the breeding herd. The meadow hayland and crested wheat grass pastures were also improved to provide winter and spring forage for the increased number of cows. The calf crop weaned and average weaning weights increased from 86 percent and 347 pound s i n 1970 to 93 percent and 363 pounds i n 1976. The total pounds of calf weaned increased 60 percent between 1970 and 1976. The tremendous increase in beef production was offset by the rampant increase in op e rating costs. The net return in 1970 was $2 , lOo but dropped to a loss of - $3,671 i n 1976. However, had the operator not increased the level of production while the operating costs increased, his net loss in 1976 would have been - $24 , 718 . Although the net returns a re negative , the increase in returns over the base level of production is positive. The internal rate of return and net present worth of the grazing system and its associated improvements was 25 percent and $95 ,027 respectively. TI1 e operator has been successful in developing his range and livestock resource and increasing calf production. It is paradoxical that the increase in returns above the base production have rendered the improvements economically profit able yet the combination of increasing operating costs and low livestock prices have produced a negative return from 1974 through 1976.

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.

Objectives were to determine: 1) whether estradiol benzoate (EB) provides a superior alternative to GnRH for synchronizing emergence, growth and maturation of a new follicular wave for fixed timed AI (TAI) in Bos indicus-influenced cattle using CIDR-based protocols, 2) the effect of 48 h calf removal at CIDR removal on the rate of maturational synchrony of the dominant follicle and 3) the effect of varying the magnitude of peak plasma progesterone (P4) concentrations following CIDR insertion on the suppression of FSH and LH secretion in a CIDR-based protocol using EB. In experiment 1, sixty-four Braford (F-1) females were stratified by BCS, parity and days postpartum and assigned randomly to one of four groups in a 2 x 2 factorial arrangement of treatments: 1) Select-Synch + CIDR, 2) Select-Synch + CIDR with 48 h calf removal, 3) E-Synch + CIDR or 4) E-Synch + CIDR with 48 h calf removal. A greater number of cattle in the EB treated group exhibited NFWE compared to the GnRH group, 29 vs 17 cows for EB and GnRH respectively, (P<0.0006). Intervals to NFWE were also greater in EB treated cattle than in GnRH treated cattle, 4.2 vs 2.7 d for EB and GnRH treated cattle respectively, (P<0.0001). Proportions of GnRH- and EB-treated cows ovulating after CIDR removal did not differ. Post-CIDR suckling status did not affect ovulation frequency or interval to ovulation. In experiment 2, eight pubertal (F-1) heifers were used in a Latin Square design with four treatment levels of P4: 1) EB only, 2) EB and new CIDR, 3) EB and new autoclaved CIDR, 4) EB, new autoclaved CIDR and P4 injection at CIDR insertion. Treatments 2 through 4 increased (P < 0.01) mean plasma P4 concentrations compared to treatment 1, with treatment 4 creating the greatest increase in P4 with the longest duration. Suppression of plasma FSH was greatest in group 4 (P<0.08), with mean 60 h concentrations less than in all other groups. Mean concentrations of LH were lesser in group 4 than groups 1 and 2. Frequencies of occurrence of NFWE and ovulation and intervals to NFWE did not differ among treatments. Results indicate that the use of EB and CIDR to synchronize Brahman x Hereford females may provide better synchronization for TAI compared to GnRH and CIDR based protocols.

Objectives were to determine: 1) whether estradiol benzoate (EB) provides a superior alternative to GnRH for synchronizing emergence, growth and maturation of a new follicular wave for fixed timed AI (TAI) in Bos indicus-influenced cattle using CIDR-based protocols, 2) the effect of 48 h calf removal at CIDR removal on the rate of maturational synchrony of the dominant follicle and 3) the effect of varying the magnitude of peak plasma progesterone (P4) concentrations following CIDR insertion on the suppression of FSH and LH secretion in a CIDR-based protocol using EB. In experiment 1, sixty-four Braford (F-1) females were stratified by BCS, parity and days postpartum and assigned randomly to one of four groups in a 2 x 2 factorial arrangement of treatments: 1) Select-Synch + CIDR, 2) Select-Synch + CIDR with 48 h calf removal, 3) E-Synch + CIDR or 4) E-Synch + CIDR with 48 h calf removal. A greater number of cattle in the EB treated group exhibited NFWE compared to the GnRH group, 29 vs 17 cows for EB and GnRH respectively, (P<0.0006). Intervals to NFWE were also greater in EB treated cattle than in GnRH treated cattle, 4.2 vs 2.7 d for EB and GnRH treated cattle respectively, (P<0.0001). Proportions of GnRH- and EB-treated cows ovulating after CIDR removal did not differ. Post-CIDR suckling status did not affect ovulation frequency or interval to ovulation. In experiment 2, eight pubertal (F-1) heifers were used in a Latin Square design with four treatment levels of P4: 1) EB only, 2) EB and new CIDR, 3) EB and new autoclaved CIDR, 4) EB, new autoclaved CIDR and P4 injection at CIDR insertion. Treatments 2 through 4 increased (P < 0.01) mean plasma P4 concentrations compared to treatment 1, with treatment 4 creating the greatest increase in P4 with the longest duration. Suppression of plasma FSH was greatest in group 4 (P<0.08), with mean 60 h concentrations less than in all other groups. Mean concentrations of LH were lesser in group 4 than groups 1 and 2. Frequencies of occurrence of NFWE and ovulation and intervals to NFWE did not differ among treatments. Results indicate that the use of EB and CIDR to synchronize Brahman x Hereford females may provide better synchronization for TAI compared to GnRH and CIDR based protocols.

The distribution, behaviours, and composition of dusky dolphin (Lagenorhynchus obscurus) nursery groups off Kaikoura, New Zealand, were examined. Data were collected during January–May 2005 and December 2005–April 2006 by systematic boat based surveys, group focal follows and photo-identification techniques. A total of 99 nursery groups were encountered on survey. Nursery groups were encountered in shallow water (<20 m) significantly more often than in deeper water (>20 m). Other group types (large groups, mating groups, adult non-mating groups) were not found in shallow water significantly more often than in deeper water. By staying in the shallower water, nursery groups may be protected from aggressive conspecifics and predators. More boats, especially private recreational boats, were found in the shallower waters, indicating that nursery groups are at greater risk from encounters with boat motors or recreational fishing gear in such areas. Group focal follows of at least 30- minutes were conducted on 56 nursery groups. Calves engaged in significantly more high energy behaviours (displays and head first re-entries) than non-calves in nursery groups. These groups were predominantly resting and compactly organized (interanimal distance less than 1 adult body length). Nursery groups showed a high level of synchrony, with 44% of groups synchronizing their submergence and surfacings for most of the focal follow. Median group size was 14, with a minimum of 2 mother-calf pairs to a maximum of 50 mother-calf pairs. A total of 260 individuals were catalogued as members of nursery groups during the two field seasons. Of these, 112 individuals were seen in nursery groups on at least two different days. Some individuals photographed with young calves in nursery groups off Kaikoura were later photographed in Admiralty Bay, 275 km northwest of Kaikoura. Other individuals photographed together in nursery groups in 2005 were also together in nursery groups in 2006.

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.

The objectives of this thesis were to investigate 1) the use of behavior and activity monitoring for the identification of heifers at risk of disease, 2) the use of group level management practices to reduce the risk of disease, and 3) the identification of long-term impacts of bovine respiratory disease complex (BRD). For objective 1, lying posture, a decreased willingness to approach an observer and high lethargy scores were associated with diarrhea in calves under 2 weeks of age and a high lethargy score in 4-6 week old calves was associated with decreased average daily gain (ADG) in the first 8 weeks of life (n = 744). In weaned calves (n = 74) increased activity (increase in steps and decrease in lying), standing at the bunk not eating, and lying far from other calves in the first 3 days post-weaning were associated with decreased post-weaning weight gain. For objective 2, separating social mixing from movement to a novel environment, and administering prophylactic antibiotics to calves at high risk of disease, were investigated. Both mixing and movement to a novel environment increased activity levels in newly weaned dairy calves (n = 64). When calves were mixed prior to movement to a novel environment they had a smaller increase in activity compared to calves that were simultaneously mixed and moved. No differences in weight gain or calf starter intake were observed. Administration of a prophylactic antibiotic, tulathromycin, to 3 day old calves upon arrival at a heifer raising facility (n = 788) and 8 week old calves at first movement to group housing (n = 1,392 ) was found to reduce diarrhea and otitis media, and BRD, respectively. Objective 3 was addressed by monitoring calves that received tulathromycin at 8 weeks of age to determine the long-term impacts of BRD. Bovine Respiratory Disease complex was associated with decreased growth to 9 months of age, decreased survival to first calving, increased risk of dystocia and a greater age at first calving. / Natural Sciences and Engineering Research Council of Canada & Pfizer Animal Health