Der Tierzuchtreport 2010 präsentiert für die Tierarten Rind, Schwein, Pferd, Schaf und Ziege umfangreiche Daten zur Entwicklung der Zucht- und Produktionsbestände sowie deren Leistungen. Er enthält außerdem ein umfangreiches Adressenverzeichnis aller mit der Tierzucht befassten Organisationen.

<p>    </p> <p>Domestication is the process by which a previously wild population is managed by humans, thereby being subjected to a different set of selective pressures than experienced in its natural setting. Its opposite, feralization, is therefore when a domesticate escapes or is released from a captive setting, reasserting natural selective pressures. The genomics underpinning both domesti- cation and feralization have not been studied in insects; the Western honey bee (<em>Apis mellifera </em>L.) is a good model for this system, as honey bees exist in both a managed and feral state, and have extensive historic and genomic resources to document population changes. My goal in this thesis was to 1) improve upon our understanding of honey bee importation and genetics to the United States to support demographic assertions, and 2) to sequence managed and feral stocks of honey bees to identify the population structure and 3) genetic differences underpinning domestication. Ultimately, I reconstructed 400 years of honey bee importation and management history, creating the most comprehensive understanding to date of importation dates and locations, historical man- agement practices, and genetic bottlenecks. Additionally, I summarized thirty years of honey bee genome sequencing to provide a road map for future studies. Then, I conducted whole genome pooled sequencing on six managed and three feral stocks of honey bees from the United States. The mitochondrial and whole genome ancestry of feral colonies holds relics from their importation history, while managed colonies show evidence of more recent importation events. The managed stocks in my sample set have higher overall genetic diversity, but exhibit little differentiation, but feral stocks exhibit varying levels of differentiation, indicating different levels of ferality likely dictated by the level of reproductive isolation from managed colonies. </p>

Maternal performance of reciprocal two-breed cross cows between Angus, Herefords and Shorthorns was compared in 249 matings over a four year period. These cows were mated to bulls of the same three breeds to produce three-breed and baekcross calvea. Shorthorn x Angus cows (sire breed first) weaned l7.S~ fewer calve. and Hereford x Angus cows 10.31 fewer calves than their respective reciprocal crosses. Thete differencea while large were not statistically significant presumably due to the small numbers involved. There was little difference between Shorthorn x Hereford and Hereford x Shorthorn cows in percentage calf crop_ The calves from Shorthorn x Angua cows were significantly heavier at birth than the calves from their reciprocals. Birth weight differences of calves from the other two sets of rec1proc41 eros. cows were not significantly different. Differences in average daily gain from birth to weaning were highly significant in calves from Angus x Hereford cows over calves from Hereford x Angus cows as well as Shorthorn x Hereford over Hereford x Shorthorn. The third set of reCiprocal crossea, Angus x Shorthorn versus Shorthorn x Hereford, did not show significant differences in average daily gains. / Master of Science

The face of animal breeding has changed significantly over the past few decades. Traditionally, the genetic improvement of both plant and animal species focussed on the selective breeding of individuals with superior phenotypes, with no precise knowledge of the genes controlling the traits under selection. Over the past few decades, however, advances in molecular genetics have led to the identification of genetic markers associated with genes controlling economically important traits, which has enabled breeders to enhance the genetic improvement of breeding stock through linkage disequilibrium marker-assisted selection. Since the integration of marker-assisted selection into breeding programmes has not been widely documented, it is important that breeders are able to evaluate the advantages and disadvantages of marker-assisted selection, in comparison to phenotypic selection, prior to the implementation of either selection strategy. Therefore, this investigation aimed to develop deterministic simulation models that could accurately demonstrate and compare the effects of phenotypic selection and marker-assisted selection, under the assumption of both additive gene action and complete dominance at the loci of interest. Six computer models were developed using Microsoft Excel, namely 'Random Mating,' 'Phenotypic Selection,' 'Marker-Assisted Selection,' 'Selection with Dominance,' 'Direct Selection' and 'Indirect selection.' The 'Random Mating' model was firstly used to determine the effects of linkage disequilibrium between two loci in a randomly mating population. The 'Phenotypic Selection' and 'Marker-Assisted Selection' models focused primarily on examining and comparing the response to these two selection strategies over five generations and their consequent effect on genetic variation in a population when the QTL of interest exhibited additive gene action. In contrast, the 'Selection with Dominance' model investigated the efficiency of phenotypic selection and marker-assisted selection under the assumption of complete dominance at the QTL under selection. Finally, the 'Direct Selection and 'Indirect Selection' models were developed in order to mimic the effects of marker assisted selection on two cattle populations utilizing both a direct and indirect marker respectively. The simulated results showed that, under the assumption of additive gene action, marker-assisted selection was more effective than phenotypic selection in increasing the population mean, when linkage disequilibrium was present between the marker locus and the QTL under selection and the QTL captured more than 80% of the trait variance. The response to both selection strategies was shown to decrease over five generations due to the decrease in genetic variation associated with selection. When the QTL under selection was assumed to display complete dominance, however, marker-assisted selection was markedly more effective than phenotypic selection, even when a minimal amount of linkage disequilibrium was present in the population and the QTL captured only 60% of the trait variance. The results obtained in this investigation were successful in simulating the theoretical expectations of markerassisted selection. The computer models developed in this investigation have potential applications in both the research and agricultural sectors. For example, the successful application of a model developed in this investigation to a practical situation that simulated markerassisted selection, was demonstrated using data from two Holstein cattle populations. Furthermore, the computer models that have been developed may be used in education for the enhancement of students understanding of abstract genetics concepts such as linkage disequilibrium and marker-assisted selection. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

No description available.

Called “The Pride of the Bluegrass,” Elmendorf Farm changed the style and substance of commercial pedigree breeding in early twentieth-century America. Between 1897 and 1914, James B. Haggin readily transformed the Kentucky farm first as a nationally preeminent horse stud, famous for its bloodlines and scales, and second as a premier dairy operation, exceptional for its sanitation, science, and size. Here rested the large-scale production of the world’s fanciest Thoroughbreds and finest milk. At the same time, Haggin’s farm reflected a lifestyle that has come to be celebrated and cherished as the ideal Kentucky landscape. A factory-style plant of large scales, of specialization, and vertical integration was disguised with the lavish iconography of portico mansions, rolling lawns, and white-planed fences, behind which million-dollar animals grazed on lush bluegrass. But a crucial, and significant, characteristic of this farm was the wage laborers who performed the back-breaking work. The labor and lives of the farm’s black workers, in particular, shows how Elmendorf helped reinforce a system of labor relations in central Kentucky, one peculiar to horse business and one segmented by race. Ultimately, this study of Elmendorf Farm shows the unforgettable imprint of Haggin’s complex personality, as well as his modern philosophies of business, but it also demonstrates conclusively the fallacy of an acquisitive nature and aggressive impulses in commercial animal breeding. As a powerful financier in the late nineteenth-century, Haggin’s perpetual objective was ever “large economies of scale.” Haggin made and lost fortunes by creating great industrial enterprises, and his Bluegrass stud proved no different—even if his individual actions meant defying the norm and jeopardizing entire industries. This best explains why the world’s greatest breeding and milking farm, in many ways, failed. When Haggin applied a dual logic of industrial and aristocratic expansion to a Kentucky breeding farm, the pedigree industry, however fragile and vulnerable, was pushed to extremes and instability of both horse and milk industries resulted. Those famed marble columns, the remaining evidence of Elmendorf Farm, now stands in a lush Bluegrass field, representing one of the most spectacular failures in modern agricultural history.

Increased rates of involuntary culling as a consequence of poorer health and fertility had led to the conclusion that dairy cows appear to be less “robust” or adaptable than in the past. A way to address these concerns in breeding programs could be to select for health and welfare by including appropriate traits in a broader breeding index. However, it is important to consider any consequences that such breeding goals may have on dairy cow temperament and welfare. There were two phases to this study. The main objective of phase I was to develop tests for measuring responsiveness to humans and novelty, aggression at the feedface and sociability in dairy cows for use on commercial farms. To allow these tests to be used on commercial farm, they must be short in duration, non-invasive and not disruptive to the daily farming routine, while at the same time allowing comparisons between an individual cow’s responses in a number of similar situations. Results from this study suggested that a standardised human approach test and a stationary visual object are reliable tests for measuring responsiveness of dairy cows to changes in their environment. Measuring behaviour at the feedface proved to be an effective measure of between cow aggression. Inter-animal distance, position in relation to the herd, behavioural synchrony and presence at the feedface proved accurate measures of sociability. The remaining part of the study (Phase II) focussed on assessing how the implantation of a breeding index can affect the temperament of dairy cows on commercial farms. The tests developed were then recorded on 402 first lactation Holstein-Friesian dairy cows selected from sires that scored high (HI) and low (LO) for robustness (health, fertility and longevity traits) to produce two treatment groups on 33 commercial farms. For the purpose of this thesis, only the results from the assessment of aggressiveness are presented. Continuous focal sampling was used to record aggressive behaviour during feeding of the HI and LO cows within the herd. Cows from the HI group were involved in more aggressive interactions, initiated more aggression and received more aggression than cows from the LO group. There was a strong influence of management factors influencing aggression such as the quality of stockmanship, feedface design and nutrition. In conclusion, daughters from sires scoring high for robustness may be expressing a greater ability to maintain position at the feedface during an aggressive interaction. This highlights the importance of assessing the correlated effects of selective breeding, in this case for robustness, on behavioural traits.

O presente estudo teve por objetivo estudar os efeitos da interação genótipos x ambientes sobre as características peso à desmama, peso ao sobreano e ganho de peso da desmama ao sobreano em bovinos de corte da raça Nelore. Foram analisados 45.697 registros de peso à desmama ajustados para 205 dias (PD), 34.773 registros de peso ao sobreano ajustados para 550 dias (PS) e 34.753 registros de ganho de peso da desmama ao sobreano (GP), originários de três fazendas localizadas nas regiões sudeste e centro-oeste do Brasil. Os componentes de variância foram estimados utilizando-se o programa MTDFREML. Os dados foram submetidos a análises de duas formas distintas: primeiramente processaram-se análises de características únicas para os dados de cada fazenda e para conjuntos de dados formados por pares de fazendas. Em seguida, processaram-se análises de características múltiplas, em que a mesma característica foi considerada como variáveis distintas em cada par de fazendas. A partir da obtenção dos valores genéticos dos animais, foram calculadas as diferenças esperadas na progênie (DEPs) dos mesmos, bem como as correlações de Pearson entre os valores das DEPs dos touros para as três características estudadas. As estimativas dos coeficientes de herdabilidade variaram de 0,17 a 0,33 para a característica PD, 0,31 a 0,48 para a característica PS e 0,11 a 0,32 para a característica GP. Os coeficientes de correlação genética encontrados variaram de 0,82 a 1,00, enquanto as correlações de Pearson entre as DEPs dos touros variaram de 0,89 a 0,99. Os resultados levam a sugerir pequeno ou nenhum efeito da interação genótipo x ambiente nos rebanhos incluídos neste estudo. / The objective of the present study was to evaluate the genotype x environment interaction effect on weaning weight, post-weaning weight and weight gain post-weaning in Nellore beef cattle herds. There were analyzed 45,697 data of weaning weight adjusted to 205 days (PD), 34,773 data of post-weaning weight adjusted to 550 days (PS) and 34,753 data of weight gain post-weaning (GP), which were collected from three farms localized in southwest and middle-east of Brazil. The variance components were estimated by MTDFREML. Those data were analyzed applying two different methods: the first proceeding was of considering single traits to the data of each farm and also to the data-set originated by pair of farms. The second method was performing the analysis of multiple traits once the same trait was considered as a distinct variable in each pair of farms. Since genetic values were obtained there were calculated the expected breeding values (EPD) of the sires as the Pearson correlations between the EPD values and the traits analyzed. The estimative of heritability coefficients ranged from 0.17 to 0.33, 0.31 to 0.48 and 11 to 0.32 to PD, PS and GP respectively. The genetic correlations varied from 0.82 to 1.00, while the Pearson correlation between the EPDs ranged from 0.96 to 0.99. The results suggest a modest or inexistent genotype x environment interaction effect in the herds evaluated.

Visando a determinar se a seleção para características que são incluídas em um índice de seleção utilizado no programa de melhoramento genético poderia aumentar o peso adulto (PA) das fêmeas, procurou-se analisar a associação entre o PA e as quatro características do índice, a saber: peso à desmama (PD), ganho de peso pós desmama em 345 dias (GP), perímetro escrotal (PE) e musculosidade (MUSC). Visando também a determinar a relação entre o PA e a precocidade sexual, analisou-se a relação entre o PA e a probabilidade de prenhez aos quatorze meses (PP14). O banco de dados utilizado incluiu 134.185 animais da raça Nelore nascidos entre 1984 e 2012, pertencentes à Agropecuária CFM, em fazendas situadas nos Estados de São Paulo, Mato Grosso do Sul e Goiás. Foram estimados os coeficientes de herdabilidade para as seis características e as correlações entre essas características, principalmente o coeficiente de correlação entre o PA e as outras cinco características. Os componentes de (co) variância foram estimados por máxima verossimilhança restrita, utilizando o pacote computacional VCE. As estimativas dos coeficientes de herdabilidade encontradas foram 0,22; 0,19; 0,50; 0,20 e 0,50 para PD, GP, PE, MUSC, PP14, respectivamente. As correlações genéticas entre PA e as características de desenvolvimento ponderal foram positivas, 0,55 (PD); 0,67 (GP); 0,07 (PE); 0,46 (MUSC). A seleção para PD e para GP poderia estar relacionada com aumento do PA das vacas. A correlação entre o peso adulto e a probabilidade de prenhez aos quatorze meses foi negativa e de baixa magnitude ( -0,03). O coeficiente de herdabilidade estimado para PP14 mostra que esta característica pode ser incluída em programas de melhoramento genético para aumentar a precocidade e fertilidade da população. O pequeno aumento constatado no peso adulto não foi suficiente para causar alteração na precocidade sexual da população. As referências na literatura sobre a correlação entre as estimativas do peso adulto e PP14 são escassas. Recomendam-se outros estudos, usando diferentes conjuntos de dados e outras abordagens. As tendências genéticas demonstram o progresso no programa de seleção ao longo dos anos para as características de crescimento estudadas aqui. / In order to determine whether selection for traits included in the selection index used in a breeding program would increase the mature weight (MW) of females, this study analyzed the association between MW and four traits composing the index: weaning weight (WW), post-weaning weight gain in 345 days (PWG), scrotal circumference (SC), and muscling score (MUSC). Additionally, the genetic relationship of MW with probability of pregnancy at 14 months (PP14) was analyzed to evaluate the association between MW and sexual precocity. The database included 134,185 Nellore animals from Agropecuária CFM born between 1984 to 2012 on farms in the states of São Paulo, Mato Grosso do Sul, and Goiás. The heritability for the six traits and the correlations between them were estimated, with special importance being given to the correlation of MW with the other five traits. The (co)variance components were estimated by the restricted maximum likelihood method. The heritability coefficients were 0.22, 0.19, 0.50, 0.22 and 0.50 for WW, PWG, SC, MUSC and PP14, respectively. The genetic correlations of MW with the growth traits were positive: 0.55 (WW), 0.67 (PWG), 0.07 (SC), and 0.46 (MUSC). Selection for WW, PWG and MUSC might be related to an increase in the MW of cows. The correlation between MW and PP14 was negative and of low magnitude (-0.03). The heritability estimates and the genetic correlations of MW with the growth traits were moderate and positive. Thus, the current selection for WW, PWG and MUSC should contribute to increase the MW of cows. MW monitoring of females is important because heavy and larger animals can be associated with higher maintenance costs. The correlation between MW and PP14 was negative and of low magnitude. This association suggests that the increase in MW of cows has no important effect on reproductive performance of the heifers and vice versa. The genetic trends obtained here demonstrate that the adopted selection index has been effective to promote genetic progress for traits related to growth.

Visando a determinar se a seleção para características que são incluídas em um índice de seleção utilizado no programa de melhoramento genético poderia aumentar o peso adulto (PA) das fêmeas, procurou-se analisar a associação entre o PA e as quatro características do índice, a saber: peso à desmama (PD), ganho de peso pós desmama em 345 dias (GP), perímetro escrotal (PE) e musculosidade (MUSC). Visando também a determinar a relação entre o PA e a precocidade sexual, analisou-se a relação entre o PA e a probabilidade de prenhez aos quatorze meses (PP14). O banco de dados utilizado incluiu 134.185 animais da raça Nelore nascidos entre 1984 e 2012, pertencentes à Agropecuária CFM, em fazendas situadas nos Estados de São Paulo, Mato Grosso do Sul e Goiás. Foram estimados os coeficientes de herdabilidade para as seis características e as correlações entre essas características, principalmente o coeficiente de correlação entre o PA e as outras cinco características. Os componentes de (co) variância foram estimados por máxima verossimilhança restrita, utilizando o pacote computacional VCE. As estimativas dos coeficientes de herdabilidade encontradas foram 0,22; 0,19; 0,50; 0,20 e 0,50 para PD, GP, PE, MUSC, PP14, respectivamente. As correlações genéticas entre PA e as características de desenvolvimento ponderal foram positivas, 0,55 (PD); 0,67 (GP); 0,07 (PE); 0,46 (MUSC). A seleção para PD e para GP poderia estar relacionada com aumento do PA das vacas. A correlação entre o peso adulto e a probabilidade de prenhez aos quatorze meses foi negativa e de baixa magnitude ( -0,03). O coeficiente de herdabilidade estimado para PP14 mostra que esta característica pode ser incluída em programas de melhoramento genético para aumentar a precocidade e fertilidade da população. O pequeno aumento constatado no peso adulto não foi suficiente para causar alteração na precocidade sexual da população. As referências na literatura sobre a correlação entre as estimativas do peso adulto e PP14 são escassas. Recomendam-se outros estudos, usando diferentes conjuntos de dados e outras abordagens. As tendências genéticas demonstram o progresso no programa de seleção ao longo dos anos para as características de crescimento estudadas aqui. / In order to determine whether selection for traits included in the selection index used in a breeding program would increase the mature weight (MW) of females, this study analyzed the association between MW and four traits composing the index: weaning weight (WW), post-weaning weight gain in 345 days (PWG), scrotal circumference (SC), and muscling score (MUSC). Additionally, the genetic relationship of MW with probability of pregnancy at 14 months (PP14) was analyzed to evaluate the association between MW and sexual precocity. The database included 134,185 Nellore animals from Agropecuária CFM born between 1984 to 2012 on farms in the states of São Paulo, Mato Grosso do Sul, and Goiás. The heritability for the six traits and the correlations between them were estimated, with special importance being given to the correlation of MW with the other five traits. The (co)variance components were estimated by the restricted maximum likelihood method. The heritability coefficients were 0.22, 0.19, 0.50, 0.22 and 0.50 for WW, PWG, SC, MUSC and PP14, respectively. The genetic correlations of MW with the growth traits were positive: 0.55 (WW), 0.67 (PWG), 0.07 (SC), and 0.46 (MUSC). Selection for WW, PWG and MUSC might be related to an increase in the MW of cows. The correlation between MW and PP14 was negative and of low magnitude (-0.03). The heritability estimates and the genetic correlations of MW with the growth traits were moderate and positive. Thus, the current selection for WW, PWG and MUSC should contribute to increase the MW of cows. MW monitoring of females is important because heavy and larger animals can be associated with higher maintenance costs. The correlation between MW and PP14 was negative and of low magnitude. This association suggests that the increase in MW of cows has no important effect on reproductive performance of the heifers and vice versa. The genetic trends obtained here demonstrate that the adopted selection index has been effective to promote genetic progress for traits related to growth.