En sélection génomique, des marqueurs de l’ADN sont utilisés pour l’évaluation des grandes races laitières. La plupart des méthodes d’évaluation génomique actuelles utilisent des SNP, bien que l’utilisation d’haplotypes de SNP apporte un plus grand polymorphisme. Il n’y avait pas d’évaluation génomique en place en 2014 pour les races régionales (Abondance, Tarentaise, Vosgienne), plaçant ces races en position de faiblesse.Notre objectif principal a été de mesurer l’intérêt de l’utilisation d’haplotypes en évaluation génomique, y compris à partir d’une population d’apprentissage multiraciale. Nous avons montré que les haplotypes conduisent à de meilleurs résultats que les SNP et que la fréquence des allèles et l’étendu du déséquilibre de liaison sont importants pour une construction optimale des haplotypes. Nous avons développé deux critères incorporant ces informations qui améliorent la précision des évaluations tout en réduisant le nombre de marqueurs utilisés.Depuis 2015, un de ces critères a été inclus dans les évaluations génomiques officielles en France. Notre approche a donné dans les races régionales une précision similaire à celle obtenue après testage sur descendance. Une évaluation génomique de routine est en place pour 3 races régionales en France depuis Juin 2016. L’utilisation d’une puce Haute Densité n’a pas amélioré sa précision, alors qu’une population d’apprentissage multiraciale a été bénéfique uniquement pour certaines races. Le génotypage des nouvelle femelles a augmenté la précision de la sélection mais l’inclusion de mutations candidates détectées dans les grandes races laitières n’a conduit qu’à une légère amélioration chez les races régionales. / In genomic selection, DNA marker information is exploited for evaluation purposes in large dairy cattle breeds. Most of the current genomic evaluation methods rely today on SNP information, although haplotypes are expected to perform better due to their higher polymorphism. In 2014, genomic evaluation had not yet been implemented in regional breeds (Abondance, Tarentaise, Vosgienne), resulting in economic weaknesses for these breeds.Our aim was to assess the use of haplotypes in genomic evaluation with focus on their performance in combination with multi-breed reference populations. We found that haplotypes outperformed individual SNP markers for genomic evaluation. We also showed that information on haplotype allele frequency and on linkage pattern are relevant to select haplotypes for evaluation purposes. Our haplotype selection criteria also allowed a significant reduction of the number of markers used for genomic prediction.One of these criteria was incorporated into the French routine genomic evaluation in 2015. The performance of such an evaluation was then assessed in four regional breeds, leading to similar or higher accuracies than current progeny testing. Consequently, routine genomic evaluation was implemented in these breeds in 2016. The use of high density genotypes did not improve the performance of genomic evaluation in these breeds, while multi-breed training populations were beneficial only in some of them. Additional genotyped females led to notable increases in selection accuracies. Inclusion of candidate mutations identified in large breeds led to only minor improvements in regional breeds.

Background – Brachycephalic dog breeds have multiple skull malformations which may lead to anatomical changes in the external auditory canal. It is our frequent observation that in the otoscopic examination of the external ear in these breeds we are unable to visualise the tympanic membrane as a consequence of extreme narrowing of the proximal ear canal. Additionally brachycephalic dogs reportedly are predisposed to otitis externa (OE) and otitis media. Objectives – To characterizse the transition of the cartilaginous ear canal to the bony meatus acusticus externus using computed tomography (CT) and to investigate a possible association with OE in brachycephalic dogs. Materials and methods – Seventy-five client-owned dogs [pugs (n = 20), French bulldogs (n = 55)] were included and assessed for OE using an owner questionnaire and otoscopic and cytological examinations. In dorsal plane CT scans, the diameter of the porus acusticus externus was measured using novel methodology. The results were compared with a normocephalic control group without preexisting otological disorders. Results – Brachycephalic dogs had a significantly smaller porus acusticus externus diameter (2.6 mm) than normocephalic dogs (5.0 mm). Of the brachycephalic dogs, 32% had OE yet this was not statistically significantly related to the diameter of the porus acusticus externus. Middle ear effusion (44%) and narrowing of the external ear canal (82.6%) were significantly more frequent in brachycephalic dogs. Only five of 150 eardrums could be visualised otoscopically. Conclusions and clinical relevance – Malformation of the porus acusticus externus causes severe stenosis of the proximal ear canal in brachycephalic dogs. A connection between stenosis of the external auditory canal and OE could not be confirmed.

No description available.

The objectives of this research were to evaluate breed differences for heat-stress resistance using age at first calving and first calving interval, and to assess breed by region interactions for seven regions of the United States for survival-related traits up to five years of age in Brown Swiss, Holstein, and Jersey cows. Age at first calving and first calving interval were studied in farms with two breeds, with Holstein and Brown Swiss or Holstein and Jersey cows. The survival-related traits were analyzed in farms with one or two breeds. Seven regions within the United States were defined: Northeast, Northwest, Central north, Central, Central south, Southwest and Southeast. The fertility traits were also analyzed in seven individual states: Wisconsin, Ohio, Oregon, California, Arizona, Florida, and Texas. Brown Swiss were older than Holsteins at first calving (833 ± 2.4 d vs. 806 ± 2.0 d in regions, and 830 ± 3.1 d vs. 803 ± 2.4 d in states), but Holsteins and Brown Swiss did not differ for first calving interval. Jerseys were younger than Holsteins at first calving and had shorter first calving intervals (P < 0.01). In data from individual states, Holsteins housed with Brown Swiss were older at first calving than Holsteins housed with Jerseys (800 ± 2.7 d vs. 780 ± 2.5 d). Holsteins housed with Jerseys had slightly shorter first calving intervals than Holsteins housed with Brown Swiss, and the interaction of "type of Holstein: with season of the first calving was highly significant (P < 0.01). Region and season effects were smaller for Jerseys than for Holsteins, thus, Jerseys showed evidence of heat-stress resistance with respect to Holsteins. Management modified age at first calving in Holsteins, depending on the type of herd they were located in. Longer calving intervals might have been partly due to voluntary waiting period to breed the cows. The survival-related traits were evaluated up to five years of age. They consisted of stayability, number of completed lactations, days lived, herd-life, and total days in milk. For herds with one breed, the order for stayability to five years of age, from longer to shorter-lived breed was: Brown Swiss, Jersey and Holstein, but for the ratio of days in milk to herd-life the order was: Holstein, Jersey and Brown Swiss, and for the ratio of days in milk to days lived, it was: Jersey, and Holstein and Brown Swiss tied. This last ordering was the same for number of lactations completed by five years of age. The results for two-breed herds were similar since Brown Swiss and Jerseys had larger (Chi-square P < 0.01) probabilities of living past five years of age than Holsteins, and for days in milk and number of lactations completed, Jerseys had higher values than Holsteins (P < 0.01), but Holsteins and Brown Swiss tied in some analyses. Breed by region interaction was always significant. If all other conditions were assumed equal, Jerseys would give fastest returns by five years of age. The overall conclusion is that Jerseys performed better for the traits analyzed, all of them highly influenced by environmental conditions. / Ph. D.

Consumer awareness of the link between dietary fats and health outcomes has led to increased demand for food products enriched with bioactive fatty acids (FA). Ruminant-derived fats, such as dairy fats, contribute significantly to the American diet and contain many unique beneficial FA, such as short- and medium-chain FA, n-3 FA, conjugated linoleic acids (CLA), vaccenic acid (VA), as well as odd-and branched-chain FA (OBCFA). Increasing these FA in dairy products by altering farm management practices, such as breed, lactation stage, and nutrition, may improve human health without a change to the diet. The overarching goal of this dissertation was to evaluate on-farm strategies to increase the content of bioactive FA in bovine milk. The first objective was to enrich milk fat with bioactive FA via supplementation with echium oil, a terrestrial oil rich in n-3 FA. Treatments were 1.5% and 3.0% dry matter as lipid encapsulated echium oil (EEO) which were compared to a control (no EEO). Milk fat contents of n-3 FA increased with EEO supplementation but the transfer of n-3 FA from EEO into milk fat was rather low (< 5%). In a subsequent trial, ruminal protection of EEO and post-ruminal release of EEO-derived FA was examined. EEO-derived FA were preferentially incorporated into plasma lipid fractions unavailable to the mammary gland. Moreover, fecal excretion of EEO-derived FA ranged from 7-14% of intake, and VA and CLA, the biohydrogenation and metabolism products of n-3 FA, increased in milk and feces with EEO supplementation. Therefore, lipid-encapsulation provided inadequate digestibility and low transfer efficiency of n-3 FA into milk. The second objective was to compare the bacterial community structure and unique bioactive FA in bacterial membranes and milk fat between Holstein (HO), Jersey (JE), and HO x JE crossbreeds (CB) across a lactation. Lactation stage had a prominent effect on rumen bacterial taxa, with Firmicutes being most abundant during early lactation. The FA composition of bacterial cells was affected by both lactation stage and genetics, and OBCFA in bacterial cells were positively correlated with several bacteria of the Firmicutes phylum. HO and CB exhibited greater contents of various bioactive FA in milk than JE. The highest content of all bioactive FA occurred at early lactation, while OBCFA were highest at late lactation. The third objective was to determine the effects of grazing a monoculture vs. a diverse pasture on rumen bacterial and protozoal taxa, their membrane FA composition, and milk FA. Microbial communities shifted in response to grazing regime accompanied with changes in their membrane FA profiles. Rumen microbiota from cows grazing a diverse pasture had higher contents of n-3 FA and VA, but lower contents of OBCFA. Microbial membrane FA correlated with microbial taxa, the contents of ALA and n-3 FA were positively correlated with the bacterial genus Butyrivibrio and the protozoal genus Eudioplodinium. Milk contents of CLA and n-3 FA increased when cows grazed a diverse pasture, while grazing a monoculture led to greater milk contents of OBCFA. In conclusion, grazing cows on a diverse pasture, when compared to genetic effects and lipid supplementation, was the most efficacious strategy to increase the content of bioactive FA in milk.

Title: Influence of race of horse and speed of it's walk on timing of muscles in hippotherapy Purposes: The goal of study is to find out if race of horse and speed of it's walk approaches muscles timing in the reverse sitting position. We also pretend quadrupedal locomotion activation. That would substantiate hippotherapy with sitting-unable children. : Methods: Surface Electromyography, physiotherapeutic screening Results: Muscles timing was different with selected races as well as with different speed of walk. Quadrupedal locomotion was certified. Keywords: hiporehabilitation, hippotherpy, reverse sitting, quadrupedal locomotion, race of a horse, surface electromyography

Thesis submitted in fulfilment of the requirements for the degree of Magister Technologiae: Agriculture in the Faculty of Applied Sciences at the Cape Peninsula University of Technology / Conjugated linoleic acid (CLA), a fatty acid (FA) present in the meat and milk of ruminant animals, is considered a functional nutrient for humans. The interest in CLA is attributed to its many health benefits, such as having anti-carcinogenic, anti-atherogenic, anti-diabetic and anti-adipogenic effects. Dairy products are a rich natural source of CLA, and preliminary research indicates that the levels in milk can vary based on cattle breed and feeding system. The Fleckvieh is a popular dual-purpose breed recently introduced to the Western Cape. It is used in crossbreeding programs with Holstein and Jersey herds to increase fertility and beef production. Holstein and Jersey cattle are the two most common South African dairy breeds, but little information is available on the effect of crossbreeding on FA content and CLA levels in the milk. The primary objective of this study was to compare milk FA composition and CLA content of these two dairy breeds and their respective Fleckvieh crosses. A second objective was to investigate the effect of lactation stage on CLA levels. Jersey (J) and Fleckvieh x Jersey (F×J) cows were kept in a pasture-based system (PBS) for the duration of the study. Holstein (H) and Fleckvieh x Holstein (F×H) cows were housed in a feedlot system and fed a total mixed ration (TMR) for the duration of the study. The FA and CLA content of feeds from these two feeding systems were also analysed and compared. All cows used in the study were housed at the Elsenburg Research Farm of the Western Cape Department of Agriculture. Milk samples were collected every 35 days from the cows in each feeding group, starting 10 days after calving. Samples were kept in a freezer at -20 °C until laboratory analyses. The total number of milk samples collected was 1044. The milk FA composition and CLA in particular were determined by gas chromatography. Differences between groups were statistically analysed by two-way repeated measures of analysis of variance (ANOVA). Results show that milk CLA levels are higher in Fleckvieh-crossbred cows when compared to purebred cows. The higher CLA content of milk from Fleckvieh crossbred cows demonstrates the feasibility of using Fleckvieh bulls in South African crossbreeding programs, and are also an indication that genetic selection for increased CLA content is possible. The analysis of lactation stage showed that milk CLA is higher during late lactation. A comparison of feed samples from the two feeding systems revealed that pasture feeding resulted in higher omega-3 FA in milk. Key words: Conjugated linoleic acid, milk fatty acids profile, diet, breed, health benefits, Fleckvieh, Holstein, Jersey, diet, pasture based system, total mixed ration system,

The diploma thesis "Selected factors on milk utility of Czech Fleckvieh dairy cows" deals with certains effects on selected cattle herd, which are detected from milk utility control. The author compares dairy cows within first and third lactations in all cases. Overview of used literature is selected into specific chapters, in first part the Czech Fleckvieh is defined with its history, characteristics, related breeds and breed utility. Another comprehensive chapter is devoted to milk utility, lactation and selected factors on animal utility. Last part of literature overview is devoted to reproduction and reproductive indicators. Second main part, which is called material and methodology, author deals with cattle herd in Jasanka s.r.o. company, judging and assessing selected factors with help of milk utility control results. Collective results are assessed through statistics.

O presente trabalho teve como objetivos estimar os efeitos da inclusão de linha materna e do DNA mitocondrial (mtDNA) nos modelos de avaliação genética, avaliar o efeito do DNA satélite em características de desenvolvimento ponderal, bem como estimar parâmetros genéticos para características de carcaça e idade ao primeiro parto. Análises do mtDNA foram realizadas a partir de sangue coletado de 457 animais da raça Nelore, linhagem Lemgruber. Para as características de desenvolvimento ponderal foram analisados 14.432 registros de produção relacionados com 16.561 animais no pedigree. Para característica reprodutiva e as de carcaça foram analisados 4.621 registros de idade ao primeiro parto e 951 registros de área de olho de lombo e espessura de gordura subcutânea, relacionados com 7.135 registros de pedigree. As estimativas dos efeitos de linha materna e DNA mitocondrial foram analisadas sob 5 modelos diferentes. Os componentes de (co)variância para idade ao primeiro parto e características carcaça foram estimados em análises uni e bicaracterísticas. Não foram encontrados efeitos significativos de linhagem materna ou de DNA mitocondrial sobre as características de produção. Entretanto, foi verificado que animais com mitocôndria de origem Bos taurus, apresentam uma pequena superioridade na média de seus valores genéticos para as características de desenvolvimento ponderal. Animais com padrão de DNA satélite B tiveram suas médias ligeiramente superiores aos outros padrões. Os efeitos da precocidade de acabamento sobre a precocidade sexual devem ser avaliados utilizando-se estruturas de dados mais adequadas. / The aim of this research was to estimate the effect of the maternal lineage and mitochondrial DNA inclusion in the genetic evaluation model for growth traits, to evaluate the satellite DNA effect in these traits and to estimate genetic parameters for carcass traits and age at first calving. Blood samples were collected to mtDNA analysis from 457 Nellore cattle. Growth traits were analyzed from 14,432 production data and 16,561 pedigree data. Reproductive and carcass traits were analyzed from 4,621 age at first calving data and 951 loin-eye area and subcutaneous fat thickness data related to 7,135 pedigree data. Maternal lineage and mitochondrial DNA estimative were analyzed under 5 different models, (co)variance components for age at first calving and carcass traits were estimated in single and multiple-trait. There were no significant effects of maternal lineage or mitochondrial DNA related to production traits, but animals harboring Bos taurus mtDNA showed a low superiority on breeding values average for growth traits and animals harboring satellite DNA B pattern also showed a low superiority related to the other patterns. Further studies are suggested to evaluate the backfat thickness precocity effect related to sexual precocity.

O presente estudo teve por objetivo estudar a variabilidade da proteína verdadeira do leite em rebanhos leiteiros do estado de São Paulo, segundo a influência da contagem de células somáticas, raça, estação do ano e tipo de sistema de alimentação. Para tanto, foram utilizados 50 rebanhos comerciais distintos, formados por três raças distribuídas da seguinte forma: 17 da raça Holandesa, seis da raça Jersey e 26 da raça Girolando. Mensalmente foram coletadas amostras de leite do tanque de expansão sendo estas analisadas em relação à composição e contagem de células somáticas pelo método automatizado, e em relação ao teor de proteína verdadeira pelo de Kjeldahl. O teor de nitrogênio total foi multiplicado por 6,38 para transformá-lo em proteína bruta do leite (PB). O teor de proteína verdadeira (PV) do leite foi calculado pela diferença entre estas duas frações nitrogenadas (PV = PB - NNP). As diferenças observadas nos teores de proteína verdadeira, quando considerados os efeitos da época do ano, raça, sistema de alimentação e contagem de células somáticas, não foram significativas, o que permitiu a formulação de uma equação, a qual possibilita determinar a proteína verdadeira de forma simplificada. Foi proposta a equação: PV = 0,1862+(1,0869 x PB) - (1,2895 x NNP) + 0,0687, com R2 = 0,82 . A utilização do teor de proteína verdadeira ao invés do teor de proteína bruta, como ainda é feito no Brasil, na calibração dos equipamentos automatizados, aumentaria de forma significativa a acurácia nos resultados de proteína do leite, permitindo aos laticínios melhor classificação dos produtores dentro dos sistemas de pagamento, remunerando os produtores de forma mais justa. / The objective of this experiment was to study the variability of the true protein of milk produced in dairy herds of Sao Paulo State, under the influence of milk somatic cell count, breeds, season of the year and production system. For this aim, fifty commercial herds were selected; these herds were divided by breeds in: 17 Holstein, six Jersey, and 26 Girolando. Milk samples from the bulk tank were collected monthly and were analyzed to determine milk somatic cell count (SCC) and milk composition by the automatic method and to determine the true protein of milk (TP) by Kjeldahl method. The total nitrogen was multiplied by a factor of 6.38 to express the results in crude protein (CP) basis. True protein of milk was determined by the equation (TP = CP - NPN). No significative effect were observed for season of the year, breed, SCC and system of production were observed and this fact aloud a confection of one equation to predict milk true protein: PV = 0,1862+(1,0869 x PB) - (1,2895 x NNP) + 0,0687, com R2 = 0,82 . The use true protein of milk instead of crude protein, like it is still used in Brazil, will increase the accuracy of protein testing, and will improve substantially the milk payment system.