Yearly calvings are essential to the sustainability of modern dairy farming. Currently, calving difficulty (or dystocia) affects one in six calvings among UK dairy herds but vary from 2 to 50% internationally. In dairy cows, despite reports of impaired performance, the extent and threshold of the effect of dystocia on health and performance remains unclear. Over the past years, there has also been increasing concerns about the levels of pain experienced by the dystocial cows. Better understanding of their parturition progress and behaviours is needed so that informed decisions on pain mitigation can be taken. Additionally, the impact of dystocia (besides stillbirth) should also be addressed in dairy calves. The objective of this study was to address the effects of a difficult calving on the health and welfare of both dairy cows and calves. Retrospective analyses of an experimental farm’s detailed records were used to relate calving difficulty with health and performance of the dairy cow. The results showed that after any difficulty at calving, dairy producers incur long-lasting shortfalls in milk sales. Dystocial cows also have impaired fertility, are more likely to leave the herd early and have a higher risk of dystocia at the following calving, thus there is a long-term detrimental impact on dystocial cows. Video monitoring of calvings allowed detailed investigation of the parturition progress and behaviours of dystocial Holstein cows giving birth to singleton liveborn calves. The study of calving behaviours and parturition progress indicated longer later stages of parturition, increased restlessness and tail raising in the six hours preceding expulsion of the calf, for dystocial cows receiving farm assistance compared with cows calving unaided. This may relate to the expression of higher levels of pain when dystocia occurs. The onset of maternal behaviour was not delayed following calving difficulty, and firm conclusions could not be drawn from investigation of some behavioural indicators of pain in the first three hours postpartum. Experimental work allowed the monitoring of a cohort of 496 calves born with various degrees of birth difficulty over two years. All but one vet assisted calves were born dead, and farmer assisted calves were more likely to be stillborn than calves born without assistance. Stillborn dystocial calves displayed larger internal damage, than stillborn eutocial calves, but they did not have a different body shape at birth than dystocial calves that survived. Dystocial dairy calves that survived the birth process had lower vigour at birth, had higher salivary cortisol, acquired lower passive immunity and received more health treatments in the neonatal period. Dystocial heifers also had higher mortality rates by weaning but had similar growth to first service. Historical records from the farm also showed that dystocial heifer calves were three times more likely to have died by weaning and by first service than calves born without assistance. For those who survived, there was, however, no indication of altered growth to weaning or subsequent impaired fertility. This may be explained by the early mortality of the most badly affected calves or by farm management. However, their high mortality rates still raise welfare concerns. Altogether, results suggest that dairy calves born with any difficulty have poorer welfare in the neonatal period and possibly beyond. The experience of any calving difficulty in dairy cattle therefore not only impairs the welfare of the cow, but also the welfare from their resulting calf. Any strategy implemented to lower the occurrence and mitigate the effects of dystocia will therefore improve the welfare of the cows, their calves and enhance the farm’s economic sustainability.

La contribution des calottes polaires à l'augmentation du niveau marin est un sujet de préoccupation majeure. Dans le cadre du réchauffement climatique, la dynamique de leurs glaciers émissaires évolue et ceux-ci accélèrent leur décharge de glace vers l'océan. En tant qu'exutoires des calottes polaires et régulateurs de leur perte de masse, la prise en compte de leur fonctionnement dans les prévisions d'augmentation du niveau marin est capitale. Cependant, les processus qui régissent leur dynamique sont mal contraints et il convient alors de réduire les incertitudes qui y sont liées. Les rétroactions entre la dynamique du front et la dynamique du glacier en sont un exemple représentatif. Dans ce cadre, cette thèse se concentre sur la modélisation de la dynamique du front de vêlage, et vise à proposer une nouvelle approche physique des mécanismes aboutissant au vêlage d'iceberg. Le travail réalisé ici couple la mécanique de l'endommagement et la mécanique de la rupture. Il intègre ainsi la dégradation progressive des propriétés rhéologiques de la glace aboutissant à la formation d'un champ de crevasses et modélise ensuite la propagation des fractures caractéristiques de l'évènement de vêlage. Ce modèle nouvellement créé est contraint sur une géométrie 2D en ligne d'écoulement du glacier Helheim, au Groenland, dont on parvient à reproduire un comportement cohérent de la partie terminale. Les tests de sensibilité menés sur chacun des paramètres introduits dans le modèle contraignent l'importance de chacun d'eux. On évalue ensuite l'impact sur la dynamique du front de deux forçages naturels couramment observés dans les fjords groenlandais : la fonte de la partie immergée du front et l'impact mécanique d'un mélange de glace (mélange de glace de mer et d'icebergs). Les résultats suggèrent que si la fonte affecte légèrement la dynamique du front, le mélange de glace provoque une réponse saisonnière d'une amplitude similaire aux variations observées dans la réalité. En frottant contre les parois du fjord, il empêche le vêlage et favorise l'avancée du glacier. On montre également que la fonte ne modifie pas le bilan de masse du glacier, mais que l'effet du mélange de glace est plus marqué. Enfin, nos résultats suggèrent que lorsque le glacier présente une extension flottante, un forçage élevé peut modifier l'équilibre du glacier et affecter plus considérablement son bilan de masse pluriannuel. / Polar ice-sheets discharge and subsequent sea level rise is a major concern. Warming climate affects the behaviour of tidewater outlets glaciers and increases their ice discharge. As they drain the ice flow toward the ocean, it is pivotal to incorporate their dynamics when modelling the ice-sheet response to global warming. However, tidewater glacier dynamics is still complicated to understand, as they are believed to involve many feedbacks. The one between calving margin dynamics and glacier general dynamics is fundamental. This PhD thesis focuses on modelling the calving front of outlet glaciers, in order to enhance the representation of physical processes occurring at their margin. To do so, we build up a new framework for calving based on damage mechanics and fracture mechanics. This allows us to represent the slow degradation of the ice rheological properties from a virgin state to the appearance of a crevasse field, as well as the rapid fracture propagation associated with calving events. Our model is then constrained within a 2D flow-line representation of Helheim Glacier, Greenland. We find some parameters sets for which the glacier behaviour is coherent with its past evolution. Sensitivity tests are carried out and they reveal the significance of each model parameter. This new calving law is then employed to study the impact of submarine frontal melting and ice mélange (heterogeneous mixture of sea-ice and icebergs) on glacier dynamics. These two forcings are usually suspected to be responsible for the seasonal variations of the calving margin. Our results show that both forcings impact the front dynamics. The melting, however, only slightly changes the front position, when the ice mélange can force the glacier front to displace up to a few kilometers. Additionally, if the melting at the front is not sufficient to affect the inter-annual mass balance, this is not obvious when forced by ice mélange. At last, our model highlights a feature which is specific to floating glaciers: for the strongest forcings, the glacier equilibrium may be modified, as well as its pluri-annual mass balance.STAR

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-09-28T00:08:27Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) diana_carla_fernandes_oliveira.pdf: 1785085 bytes, checksum: d17d274bbea7e02f58960e76d1bbefd1 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-10-09T14:14:50Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) diana_carla_fernandes_oliveira.pdf: 1785085 bytes, checksum: d17d274bbea7e02f58960e76d1bbefd1 (MD5) / Made available in DSpace on 2017-10-09T14:14:50Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) diana_carla_fernandes_oliveira.pdf: 1785085 bytes, checksum: d17d274bbea7e02f58960e76d1bbefd1 (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O Brasil ? um pa?s que se destaca pela produ??o de leite, ocupando a quinta posi??o mundial, segundo o Instituto Brasileiro de Geografia e Estat?stica (IBGE, 2015). O rebanho leiteiro brasileiro ? composto em sua maior parte por animais zebu?nos e mesti?os (cruzamento entre ra?as europeias e zebu?nas). Dentre as ra?as zebu?nas, o Gir e o Guzer? se destacam pela produ??o de carne ou leite, al?m de serem animais que se adaptam bem as condi??es do clima. Por muitos anos os programas de melhoramento gen?tico de gado de leite tinham como principal preocupa??o as caracter?sticas de produ??o. Todavia, o sucesso econ?mico da pecu?ria leiteira n?o est? associado apenas ? efici?ncia produtiva, mas tamb?m ? efici?ncia reprodutiva, sa?de e longevidade do rebanho. Contudo, os ganhos em produtividade levaram a redu??o na efici?ncia das caracter?sticas reprodutivas e ao decl?nio na longevidade. A longevidade ? uma caracter?stica altamente desej?vel em rebanhos leiteiros, em raz?o da sua rela??o com a lucratividade, pois em rebanhos com vacas mais longevas, tem-se uma redu??o com o custo de animais para reposi??o. Entretanto, a longevidade ? uma caracter?stica complexa influenciada por diversos fatores, como produ??o de leite, bem estar, endogamia e objetivos de cria??o. Al?m disso, a maioria das medidas de longevidade s?o obtidas tardiamente na vida da vaca ou at? mesmo ap?s a sua morte. Este fato, faz com que a sele??o direta para a longevidade seja impratic?vel devido ao tempo necess?rio para se obter a medida, bem como o longo intervalo de gera??es, sendo uma caracter?stica de baixa herdabilidade. Portanto, a sele??o indireta para longevidade tem sido utilizada por meio da sele??o de outras caracter?sticas de interesse econ?mico, expressas precocemente, como a idade ao primeiro parto, podendo contribuir para obten??o de ganhos gen?ticos. Sendo assim, o estudo das caracter?sticas de longevidade e as outras caracter?sticas de import?ncia econ?mica s?o indispens?veis para inclus?o da longevidade em programas de melhoramento gen?tico para produ??o de leite. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / Brazil is a country that stands out for milk production, ranking fifth in the world, according to the Brazilian Institute of Geography and Statistics (IBGE, 2015). The Brazilian dairy herd is mostly composed of zebu and mestizo animals (crossbreeding between European and zebu breeds). Among the zebu breeds, the Gir and Guzer? stand out for the production of meat or milk, besides being animals that adapt well the conditions of the climate. For many years the genetic improvement programs of dairy cattle had as main concern the production characteristics. However, the economic success of dairy farming is not only related to the productive efficiency, but also to the reproductive efficiency, health and longevity of the herd. However, gains in productivity led to a reduction in the efficiency of reproductive traits and a decline in longevity. Longevity is a highly desirable characteristic in dairy herds, because of its relation to profitability, since in livestock with longer cows, there is a reduction with the cost of replacement animals. However, longevity is a complex feature influenced by many factors, such as milk production, well-being, endogamy and creation goals. In addition, most longevity measures are obtained late in the life of the cow or even after death.This fact makes the direct selection for longevity impractical due to the time required to obtain the measure, as well as the long generation interval, being a characteristic of low heritability. Therefore, indirect selection for longevity has been used through the selection of other characteristics of economic interest, expressed early, such as age at first calving, and may contribute to obtain genetic gains. Thus, the study of longevity characteristics and other characteristics of economic importance are indispensable for inclusion of longevity in genetic breeding programs for milk production.

The aim of this thesis was to evaluate the chosen effects of control of performance on the growth of calves in the most common meat breeds of the South Bohemian region (Aberdeen Angus, Charolais, Limousine, Beef Simmental) involved in the monitoring of performance of beef cattle during the period 2009 - 2014. The aim of this thesis was to evaluate what influences affect the weight of beef calves during their rearing. When comparing the average weight of calves according to breed, the highest weight at birth were (42.37 kg), at 120 days (191.32 kg), at 210 days (307.65 kg) and at 365 days (503.53 kg) with the Charolais breed. When examining the influence of year of calving at the birth weight at 120, 210, and 365 days, it was found that calves of Limousine breed clearly reached the highest weight in 2012 in all age categories. In determining the effect of month of calving for the birth weight at 120 and 210 days of age, the best months are December to March for Aberdeen Angus and April was the best month for calving for Beef Simmental. The period of calving is going from winter until spring months. Aberdeen Angus cows up to the fifth calving make up 73.29 % of the herd. When examining the influence of calving order to calves weighing at 120, 210 and 365 days of age, the worst of all breeds are calves from the first calving. At 120 and 210 days of age, Aberdeen Angus calves were at the highest weight with the 6th calving, Limousine breed were at the highest weight of calves with the 9th calving. At 365 days of age, Aberdeen Angus calves had the highest weight with the third calving. Rearing management breed is clearly the best with breeders who participate in national exhibitions and produce bulls and heifers. Relative breeding values of the Fathers for Direct effect - growth (Peru) and relative breeding values for maternal maternal effect - growth (Meru), have verifiable affect on the weight of calves

This thesis examines the influence of the level of rearing and age at first calving on performance and longevity of Holstein dairy cattle in the company ZD Krásná Hora nad Vltavou C. The quantity of milk per kg in the first lactation, functional longevity in kg of milk, functional longevity and longevity in days belong among the indicators observed by cows of Holstein cattle. The results of the monitored herds can be concluded that extension of age at first calving is statistically significant on the amount of milk in the first lactation, on functional longevity in kg of milk, on functional longevity and longevity in days. In contrast, no significant influence of the weight was elicited by observed indicators. The highest longevity in the monitored herd was achieved by the cows that were excluded for a difficult birth and also achieved the highest milk yield for functional longevity in kg milk and observation for the highest average in the number of lactations for life.

Resumo: Conhecer o comportamento dos bubalinos é importante para estabelecer práticas de manejo que favoreçam o bem-estar e bom desempenho produtivo. Com os objetivos de descrever o comportamento de búfalos nas primeiras horas após o parto e investigar as causas de falhas na primeira mamada, foram observadas 42 búfalas e seus bezerros, em três propriedades produtoras de leite. Os registros foram realizados nas primeiras horas após o parto, utilizando-se amostragem focal e coleta contínua em partos ocorridos de agosto de 2007 a novembro de 2008. As variáveis consideradas para búfalas foram: Tempo deitada (TD); Tempo de contato com a cria (TCC); Tempo de contato com a cria nos primeiros 30 min. (TCC30), Tempo em outras atividades (TOA) e Tempo sem atividade aparente (TSAA). Para os bezerros: Latências para ficar em pé (LP), para tentar mamar (LTM) e para mamar (LM). Bezerros filhos de búfalas com problemas no aparelho mamário tiveram dificuldade em obter o colostro. Nos partos com falha na mamada as mães passaram mais tempo deitadas, sem atividade aparente e cuidaram menos do bezerro (TCC30). A latência do bezerro para ficar em pé afetou TD da mãe. As búfalas primíparas dedicaram-se menos ao bezerro nos primeiros 30 min. que as de duas ou mais crias. A interferência de outras búfalas (INTERF30) diminuiu o tempo que a mãe cuidou da cria (TCC30) nos primeiros 30 min. As variáveis LTM e LM tiveram efeito de TCC30. Sugere-se o cuidado no manejo de búfalas primíparas e de úberes pendulosos e/ou tetos grossos e compridos. O ambiente necessita ser mais estudado a fim de que sejam diminuídas a interferências de outras búfalas no relacionamento búfala-bezerro. / Abstract: Knowing the bubalines behavior is important to stablish management practics in impruve the welfare as well the productive performance. Aiming describe bufaloes behavior at the first hours after birth and investigate causes of first suckling missing, 42 female bufaloes in conjunction with its calves were observed in three dairy farms. Registers were done at the first hours after birth, using a focal and continuous sampling colecting in births happened from August 2007 to November 2008. The variables considered to the bufaloes were: Laytime (LT); Calves' Time Contact (CTC); Calves' Time Contact at the 30-first minutes (CTC30); Time in Other Activities (TOA) and Time in Apparent Leisure (TAL). To the calves: Stand up Latency (SL), to Try suckling (TSL) and to suckling (SL). Calves which mother had mamal aparel problems had difficulty in obtain the colostrum. In missedsuckling births mothers spent higher time laid, with apparent leisure and took care less of their calves (CTC30). The calf latency to stand up affected mother's LT. The primipare buffaloes took less care to their calves in the firsts 30 minutes than the multiparous. The other buffaloes interference (INTERF30) minimize the CTC30. The TSL and SL had the CTC30's effect. It is suggested the primipare buffaloes and pendant udders and/or thick and long teats require carefull manegement. The environment needs more studies in order to minimize the other buffaloes interference in the buffalo-calf relationship. / Orientador: Humberto Tonhati / Coorientadora: Luciandra Macedo de Toledo / Banca: Evaldo Antonio Lencione Titto / Banca: Mateus José Rodrigues Paranhos da Costa / Mestre

Made available in DSpace on 2014-06-11T19:28:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-27Bitstream added on 2014-06-13T20:57:58Z : No. of bitstreams: 1 araujo_dn_me_jabo.pdf: 592600 bytes, checksum: f6939d288d49b1a4a3f589b1a565688d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Conhecer o comportamento dos bubalinos é importante para estabelecer práticas de manejo que favoreçam o bem-estar e bom desempenho produtivo. Com os objetivos de descrever o comportamento de búfalos nas primeiras horas após o parto e investigar as causas de falhas na primeira mamada, foram observadas 42 búfalas e seus bezerros, em três propriedades produtoras de leite. Os registros foram realizados nas primeiras horas após o parto, utilizando-se amostragem focal e coleta contínua em partos ocorridos de agosto de 2007 a novembro de 2008. As variáveis consideradas para búfalas foram: Tempo deitada (TD); Tempo de contato com a cria (TCC); Tempo de contato com a cria nos primeiros 30 min. (TCC30), Tempo em outras atividades (TOA) e Tempo sem atividade aparente (TSAA). Para os bezerros: Latências para ficar em pé (LP), para tentar mamar (LTM) e para mamar (LM). Bezerros filhos de búfalas com problemas no aparelho mamário tiveram dificuldade em obter o colostro. Nos partos com falha na mamada as mães passaram mais tempo deitadas, sem atividade aparente e cuidaram menos do bezerro (TCC30). A latência do bezerro para ficar em pé afetou TD da mãe. As búfalas primíparas dedicaram-se menos ao bezerro nos primeiros 30 min. que as de duas ou mais crias. A interferência de outras búfalas (INTERF30) diminuiu o tempo que a mãe cuidou da cria (TCC30) nos primeiros 30 min. As variáveis LTM e LM tiveram efeito de TCC30. Sugere-se o cuidado no manejo de búfalas primíparas e de úberes pendulosos e/ou tetos grossos e compridos. O ambiente necessita ser mais estudado a fim de que sejam diminuídas a interferências de outras búfalas no relacionamento búfala-bezerro. / Knowing the bubalines behavior is important to stablish management practics in impruve the welfare as well the productive performance. Aiming describe bufaloes behavior at the first hours after birth and investigate causes of first suckling missing, 42 female bufaloes in conjunction with its calves were observed in three dairy farms. Registers were done at the first hours after birth, using a focal and continuous sampling colecting in births happened from August 2007 to November 2008. The variables considered to the bufaloes were: Laytime (LT); Calves’ Time Contact (CTC); Calves’ Time Contact at the 30-first minutes (CTC30); Time in Other Activities (TOA) and Time in Apparent Leisure (TAL). To the calves: Stand up Latency (SL), to Try suckling (TSL) and to suckling (SL). Calves which mother had mamal aparel problems had difficulty in obtain the colostrum. In missedsuckling births mothers spent higher time laid, with apparent leisure and took care less of their calves (CTC30). The calf latency to stand up affected mother’s LT. The primipare buffaloes took less care to their calves in the firsts 30 minutes than the multiparous. The other buffaloes interference (INTERF30) minimize the CTC30. The TSL and SL had the CTC30’s effect. It is suggested the primipare buffaloes and pendant udders and/or thick and long teats require carefull manegement. The environment needs more studies in order to minimize the other buffaloes interference in the buffalo-calf relationship.

A consequence of climate change is rising global sea levels, predicted to bring increased socio-economic and environmental impacts to coastal communities. The Greenland Ice Sheet has become a prominent contributor to rising sea levels, a consequence of the Arctic warming at twice the rate of the global average. Mass loss from the ice sheet is separated between changes in surface mass balance and ice discharge at marine terminating outlet glaciers, with the later dominating mass loss over the past fifty years. While advances in ice sheet modelling have provided greater clarity on Greenland’s future mass loss, there remains inefficiencies in modelling the response of outlet glaciers in Greenland’s fjords. This thesis aims to provide greater insight into behaviour of Kangerlussuaq Glacier, SE Greenland, by employing a 2D flowline model to understand the processes governing ice dynamics and to explore how the glacier may respond to a warming climate. Results indicate that the presence of a winter ice mélange is the principle dictator of Kangerlussuaq Glacier’s behaviour and likely protects against further retreat towards a reverse sloped section of bedrock. However, if such a retreat does materialise, then large overdeepenings in Kangerlussuaq Fjord raise the spectre of uncontrollable retreat and excessive mass loss.

The population trajectory of woodland caribou (Rangifer tarandus caribou) in Newfoundland is currently determined by low calf survival due to high predation rates during the first 6-8 weeks after parturition. Most caribou in Newfoundland congregate and give birth in open calving grounds; consequently, in order to investigate predator-prey interactions, design research, and develop mitigation strategies, the geographic extent of the caribou calving grounds must be properly identified. We used VHF telemetry locations of caribou calves, collected from 2003-2010, to determine the spatial and temporal extent of caribou calving grounds in three study areas in Newfoundland. We put GPS collars on 47 black bears (Ursus americanus) in 3 caribou ranges where bears are having a significant impact on caribou recruitment by preying on calves during the calving season. Bear movements were greatest during the calving season, potentially increasing encounters with calves. Some bears migrated to the calving grounds just prior to caribou parturition, indicating deliberate broad-scale selection of areas of high calf density. Bears displayed interannual fidelity to calving ground usage patterns during the calving season, with some bears using the calving grounds every year, while others did not. We estimated the probability of a bear spending time in the calving grounds during the calving season as a function of the bear’s sex and mean distance to the calving grounds with logistic regression. We found that as distance increased, the odds of a bear spending time in the calving grounds decreased, and that at any given distance the odds were greater for male bears than for female bears. Our results indicate that some bears in Newfoundland are likely caribou calf predators, while others are not, and that the sex and broad-scale distribution of bears influenced the probability of a bear participating in calf predation during the calving season. The probability distribution of calf-visiting bears could be used to develop management practices to mitigate the impact of bear predation on declining caribou herds in Newfoundland.

No description available.