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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Intake, digestion site, extent of digestion and digesta kinetics in grazing lactating cows /

Berzaghi, Paolo, January 1993 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 67-75). Also available via the Internet.
2

Effects of estrus and disease states on daily milk production and their application to computer assisted management of dairy cows

Palmer, Roger William, January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 238-240).
3

Effect of selective dry cow therapy on udder health of US dairy herds

Torres, Audrey H. January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Full text release at OhioLINK's ETD Center delayed at author's request
4

Consumer acceptability and consumption of milk

Harries, Eleanor January 1991 (has links)
No description available.
5

Production and reproduction performance of Jersey and Fleckvieh × Jersey cows in a pasture-based system

Goni, Sindisile 04 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Genetic selection for high milk production, type and appearance for the last 50 years has suppressed secondary traits such as reproductive performance, productive life, health and survivability in the pure milk breeds. The economic importance of these secondary traits in dairy production systems is the basis for the interest seen in crossbreeding. The problem of growth rate of heifers, cow fertility, reduced disease resistance and small body frame for beef production in Jerseys can be improved by crossing Jerseys with dual purpose breeds, such as Fleckviehs which possess a more beef potential. Against this background, this study aimed at comparing the production and reproduction of Jersey and Fleckvieh × Jersey cows in a pasture-based system. Milk recording was done according to standard milk recording procedures. Milk production (milk, fat, and protein yield) was adjusted to 305 days of lactation and corrected for age at calving. Effects of breed, parity, month and year were estimated for milk, fat and protein yield as well as fat and protein percentage using general linear models procedure. The fixed effects identified as having significant effects on milk, fat and protein yield were breed, parity and year. F×J cows produced significantly more milk than J cows (6141 ± 102 vs. 5398 ± 95 kg milk). Protein and fat yield were significantly higher in F×J (201 ± 3 and 272 ± 4 kg, respectively) than in J cows (194 ± 2 and 246 ± 3 kg, respectively). There percentages of fat and protein differed slightly between the two breeds with the Jersey recording slightly higher percentages (4.61 ± 0.04 and 3.62 ± 0.03 %, respectively) compared to the F×J cows’ percentages, which were, respectively, 4.47 ± 0.04 and 3.51 ± 0.03 %. It was concluded that F×J crossbred cows were more productive than purebred J cows probably owing to heterotic effects. Heifers were inseminated at 13 months of age and cows 40 days post-calving. Using insemination records and pregnancy check results, fertility traits were analyzed and compared between the two breeds, using analysis of variance for continuous records. Conception age was the same for both breeds resulting in a similar age at first calving. For cows, the interval from calving to first insemination was significantly shorter (P <0.001) in crossbred cows being 76.7 ± 2.2 days compared to 82.4 ± 2.5 days for purebreds. A larger proportion (P < 0.001) of 0.70 for crossbred cows was inseminated within 80 days after calving compared to 0.54 for J cows. Although the absolute number of days between calving and conception (DO) was lower for F×J cows in comparison to J cows (104.8 ± 6.8 vs. 114.8 ± 8.1days, respectively), the difference was not significant. However, the proportion of F×J cows confirmed pregnant by 100 days in milk was 0.79, which was higher (P < 0.001) than the 0.66 for J cows. Results indicate the potential of improving reproductive performance of J cows through crossing with dual-purpose breeds. The beef production of purebred J and Fleckvieh x Jersey (F×J) bull calves was compared, where bull calves were reared similarly for veal, i.e. carcass weight not exceeding 100 kg, or as steers for beef to 21 months of age. In both the veal and steer production systems, the mean birth weight were higher (P < 0.001) for crossbred in comparison to J calves and steers (33.5 ± 1.2 kg vs. 27.9 ± 1.2 kg for veal) and (33.4 ± 0.9 kg vs. 26.9 ± 0.9 kg for steers) respectively. The live weight at 6 months of age was 163.5 ± 3.9 kg for J bull calves, which was lower (P < 0.001) than that for F×J bull calves (180.6 ± 4.0 kg). The F×J bull calves had a significantly higher average daily gain (ADG) of 0.82 ± 0.02 kg/day compared to 0.73 ± 0.02 kg/day for J bulls. Marketing age differed (P < 0.001) in the veal production system with F×J and J bull calves marketed at 7.1 ± 0.1 and 6.3 ± 0.1 months, respectively. End live weight at 21 months of age was significantly higher (P < 0.001) in F×J bulls (441.4 ± 14.9 kg) than the 322.6 ± 13.4 kg in J bulls; while ADG differed (P < 0.001) between the two breeds being 0.64 ± 0.02 and 0.46 ± 0.0 kg/day in F×J and J bull calves, respectively. Crossbred steers had a significantly higher carcass of 206.5 ± 8.9 kg compared to 157.9 ± 8.6 kg for J steers. Results indicate the potential of improving beef production characteristics of the J cattle through crossbreeding. / AFRIKAANSE OPSOMMING: Genetiese seleksie vir hoë melkproduksie, tipe en voorkoms die afgelope 50 jaar het sekondêre eienskappe soos reproduksie, produktiewe lewe, gesondheid en oorlewing onderdruk in die suiwer melk rasse. Die ekonomiese belangrikheid van hierdie sekondêre eienskappe in melkproduksie stelsels is die basis vir kruisteling. Probleme soos groei tempo van verse, koei vrugbaarheid, verlaagde weerstandbiedenheid teen siektes en klein liggaam raam vir vleisproduksie in Jerseys kan verbeter word deur die kruising van Jerseys met ' n dubbele doel rasse, soos Fleckviehs wat beskik oor beter vleis potensiaal. Teen hierdie agtergrond, is hierdie studie daarop gemik om produksie en reproduksie van Jersey en Fleckvieh x Jersey koeie in 'n weiveld - gebaseerde stelsel te vergelyk. Melk opname is gedoen volgens standaard melkaantekening prosedures. Melkproduksie (melk-, veten proteïen opbrengs) was aangepas vir 305 dae van laktasie en gekorrigeer vir kalf ouderdom. ‘n Algemene lineêre model was gebruik om die effekte van ras, pariteit , maand en jaar op melk-, vet- en proteïen opbrengs sowel as vet- en proteïen persentasie te bepaal. Die vaste effekte geïdentifiseer met 'n beduidende effek op melk-, vet- en proteïen opbrengs was ras, pariteit en jaar. F × J koeie het aansienlik meer melk as J koeie (6141 ± 102 teen 5398 ± 95 kg melk) produseer . Vet opbrengs was aansienlik hoër in F × J koeie as in J koeie (272 ± 4 246 teen ± 3 kg vet). Proteïen opbrengs was ook aansienlik hoër in F × J koeie as J koeie (201 ± 3 vs 194 ± 2 kg proteïen). Vet en proteïen persentasies het geneig om effens te verskil met 'n klein effek (4.61 ± 0.04 % vet en 3.62 ± 0.03 % proteïen) vir J koeie en (4.47 ± 0.04 % vet en 3.51 ± 0.03 % proteïen) vir F × J koeie. Daar is tot die gevolgtrekking gekom dat F × J gekruisde koeie kan meer produktief wees as suiwer J koeie weens heterotiese effekte. Verse kunsmatig geïnsemineer was op 13 maande ouderdom en koeie 40 dae na- kalwing aangehou was. Met behulp van bevrugting en swangerskap rekords, is vrugbaarheid eienskappe ontleed en vergelyk tussen die twee rasse, met behulp van ontleding van variansie vir deurlopende rekords. Ouderdom van bevrugting was dieselfde vir beide rasse wat in 'n soortgelyke ouderdomsgroep was by eerste kalwing. Vir koeie was die interval van kalf tot eerste inseminasie aansienlik korter (P < 0.001) vir kruisgeteelde koeie wat 76.7 ± 2.2 dae in vergelyking met 82.4 ± 2.5 dae suiwerrasse is. ‘n Groter proporsie ( P < 0.001) van 0.70 vir gekruisteelde koeie is binne 80 dae na kalwing geïnsemineer in vergelyking met 0.54 vir J koeie. Alhoewel die absolute aantal dae tussen kalwing en opvatting (DO) laer was vir F × J koeie in vergelyking met J koeie (104.8 ± 6.8 teen 114.8 ± 8.1dae, onderskeidelik), is die verskil nie betekenisvol nie. Maar die verhouding van F × J koeie wat swanger bevestig is met 100 dae in melk was 0.79, wat hoër was (P < 0.001) is as die 0.66 vir J koeie. Resultate dui daarop dat daar potensiaal is reproduktiewe prestasie te verbeter van J koeie deur kruisteling met 'n dubbel- doel rasse. Die vleisproduksie van suiwer J en Fleckvieh x Jersey (F × J) bulkalwers vergelyk. Die bul kalwers is soortgelyk grootgemaak vir kalfsvleis, d.w.s karkas gewig mag nie 100 kg oorskry as bulkalwers nie, en as osse vir vleis tot 21 maande oud. In die kalwers- en os produksie stelsels, was die gemiddelde geboorte gewig hoër (P < 0.001) vir die kruise in vergelyking met J kalwers en osse (33.5 ± 1.2 kg teen 27.9 ± 1.2 kg vir kalwers) en (33.4 ± 0.9 kg vs . 26.9 ± 0.9 kg vir osse) onderskeidelik . Die lewendige gewig op 6 maande ouderdom was 163.5 ± 3.9 kg vir J bulkalwers en was hoër (P < 0.001) vir F × J bulkalwers 180.6 ± 4.0 kg. Die F × J bul kalwers het 'n aansienlik ‘n hoër gemiddelde daaglikse toename (GDT) van 0.82 ± 0.02 kg/dag in vergelyking met 0.73 ± 0.02 kg/dag vir J bulle. Bemarkingsouderdom verskil (P < 0.001) in die kalf produksie stelsel met F × J en J bulkalwers bemark op 7.1 ± 0.1 en 6.3 ± 0.1 maande , onderskeidelik. Finale lewendige gewig van 21 maande oud was aansienlik hoër 441.4 ± 14.9 kg in F × J bulle as 322.6 ± 13.4 kg in J bulle , terwyl GDT hoër was (P < 0.001), met 0.64 ± 0.02 kg/dag en 0.46 ± 0.0 kg/dag in F × J en J bulkalwers, onderskeidelik. Gekruisde osse het 'n aansienlik hoër karkasgewig 206.5 ± 8.9 kg in vergelyking met 157.9 ± 8.6 kg van J osse. Resultate dui daarop dat daar potensiaal is om die beesvleis produksie-eienskappe van die J beeste te verbeter d.m.v. kruisteling.
6

Adaptação do teste de provocação oral duplo cego placebo controlado para o diagnóstico de alergia às proteínas do leite de vaca mediada pela imunoglobulina E, na faixa etária pediátrica / Adaptation of the double blind placebo controlled oral food challenge for the cows milk allergy diagnosis mediated by immunoglobulin E, in pediatric age

Andrea Keiko Fujinami Gushken 03 March 2009 (has links)
O Teste de Provocação Oral Duplo Cego Placebo Controlado (TPODCPC) é considerado um método diagnóstico de extrema importância na alergia alimentar, entretanto não existe, em nosso meio, uma padronização em relação aos materiais e métodos para a sua execução, especialmente na faixa etária pediátrica. O objetivo deste estudo foi adaptar TPODCPC para o diagnóstico de alergia às proteínas do leite de vaca (APLV) mediada por IgE, em crianças e adolescentes. O objetivo secundário foi descrever a relação entre os antecedentes de atopia associados a dados laboratoriais e os resultados dos TPODCPC. Foram incluídos 58 pacientes que se dividiram em dois grupos. O grupo 1 foi composto por 39 pacientes (mediana de idade: 5,3 anos; 1,6M:1F) com história sugestiva de APLV IgE mediada, sem relato de história de anafilaxia recente e com pesquisa positiva de IgE específica para leite de vaca (LV) e/ou frações. No grupo 2 foram incluídos 19 pacientes (mediana de idade: 8,3 anos; 1,4 M:1F) sem história sugestiva de APLV. Os itens avaliados na adaptação deste método diagnóstico incluíram: escolha do local, materiais a serem utilizados e operacionalização do teste. O hospital dia mostrou-se, por suas características, adequado à realização do exame. Em relação aos materiais escolhidos para a oferta do veículo, os recipientes opacos e vedados revelaram-se mais adaptados às necessidades do teste, os veículos de maior aceitação foram sopa de legumes e bebida à base de soja e o LV a ser oferecido de maneira mais apropriada foi na forma líquida e com baixo teor de lactose. As dificuldades observadas na realização do TPODCPC não comprometeram a sua execução, entretanto houve dificuldade na interpretação dos resultados especialmente nos pacientes com sintomas como pápulas periorais ou achados clínicos inespecíficos. Observou-se concordância entre os critérios clínico-laboratoriais adotados para a definição dos grupos 1 e 2 com os resultados do TPODCPC. Em conclusão, o teste mostrou-se exeqüível e seguro e a adaptação deste para o diagnóstico de APLV IgE mediada nesta faixa etária pediátrica foi possível, sendo necessária a avaliação da sua reprodutibilidade em outras populações. / The Double Blind Placebo Controlled Food Challenge (DBPCFC) is considered an important method for food allergy diagnosis, nevertheless it is not standardized among us. The aim of this study was to adapt DBPCFC for cows milk allergy (CMA) diagnosis in children and adolescents. A secondary aim was to describe the relation between history of atopy and laboratorial findings with DBPCFC results. It was included 58 patients that were distributed in two groups. Group 1 was composed of 39 patients (median age: 5,3 years; 1,6M:1F) with suggestive history of CMA without recent anaphylaxis, and specific IgE to cow´s milk (CM) and/or its fractions. In group 2 was included 19 patients (median age 8,3 years; 1,4 M:1F) where the CMA diagnosis was excluded based on clinical findings. The items evaluated in the adaptation of this method were: setting choice, kind of milk processing and vehicles, besides material and test performance. Day hospital was considered adequate for this test. Regarding to elected materials to offer the vehicle, opaque and sealed recipients showed more suitable to test demands. Vehicles more accepted were legumes soup and soy beverage and the most adequate CM to be offered was liquid and with low lactose concentration. The difficult observed in performance of DBPCFC do not compromise its execution, however the interpretation of the results was very difficult specially in patients with perioral wheals and unspecific clinical findings. There is an agreement Comparing adopted clinical and laboratorial criterion for definition of group 1 and 2 with DBPCFC results. In conclusion, the test proved to be feasible and safe and its adaptation is possible for IgE mediated CMA diagnosis, being necessary to evaluate its reproducibility in other populations.
7

Adaptação do teste de provocação oral duplo cego placebo controlado para o diagnóstico de alergia às proteínas do leite de vaca mediada pela imunoglobulina E, na faixa etária pediátrica / Adaptation of the double blind placebo controlled oral food challenge for the cows milk allergy diagnosis mediated by immunoglobulin E, in pediatric age

Gushken, Andrea Keiko Fujinami 03 March 2009 (has links)
O Teste de Provocação Oral Duplo Cego Placebo Controlado (TPODCPC) é considerado um método diagnóstico de extrema importância na alergia alimentar, entretanto não existe, em nosso meio, uma padronização em relação aos materiais e métodos para a sua execução, especialmente na faixa etária pediátrica. O objetivo deste estudo foi adaptar TPODCPC para o diagnóstico de alergia às proteínas do leite de vaca (APLV) mediada por IgE, em crianças e adolescentes. O objetivo secundário foi descrever a relação entre os antecedentes de atopia associados a dados laboratoriais e os resultados dos TPODCPC. Foram incluídos 58 pacientes que se dividiram em dois grupos. O grupo 1 foi composto por 39 pacientes (mediana de idade: 5,3 anos; 1,6M:1F) com história sugestiva de APLV IgE mediada, sem relato de história de anafilaxia recente e com pesquisa positiva de IgE específica para leite de vaca (LV) e/ou frações. No grupo 2 foram incluídos 19 pacientes (mediana de idade: 8,3 anos; 1,4 M:1F) sem história sugestiva de APLV. Os itens avaliados na adaptação deste método diagnóstico incluíram: escolha do local, materiais a serem utilizados e operacionalização do teste. O hospital dia mostrou-se, por suas características, adequado à realização do exame. Em relação aos materiais escolhidos para a oferta do veículo, os recipientes opacos e vedados revelaram-se mais adaptados às necessidades do teste, os veículos de maior aceitação foram sopa de legumes e bebida à base de soja e o LV a ser oferecido de maneira mais apropriada foi na forma líquida e com baixo teor de lactose. As dificuldades observadas na realização do TPODCPC não comprometeram a sua execução, entretanto houve dificuldade na interpretação dos resultados especialmente nos pacientes com sintomas como pápulas periorais ou achados clínicos inespecíficos. Observou-se concordância entre os critérios clínico-laboratoriais adotados para a definição dos grupos 1 e 2 com os resultados do TPODCPC. Em conclusão, o teste mostrou-se exeqüível e seguro e a adaptação deste para o diagnóstico de APLV IgE mediada nesta faixa etária pediátrica foi possível, sendo necessária a avaliação da sua reprodutibilidade em outras populações. / The Double Blind Placebo Controlled Food Challenge (DBPCFC) is considered an important method for food allergy diagnosis, nevertheless it is not standardized among us. The aim of this study was to adapt DBPCFC for cows milk allergy (CMA) diagnosis in children and adolescents. A secondary aim was to describe the relation between history of atopy and laboratorial findings with DBPCFC results. It was included 58 patients that were distributed in two groups. Group 1 was composed of 39 patients (median age: 5,3 years; 1,6M:1F) with suggestive history of CMA without recent anaphylaxis, and specific IgE to cow´s milk (CM) and/or its fractions. In group 2 was included 19 patients (median age 8,3 years; 1,4 M:1F) where the CMA diagnosis was excluded based on clinical findings. The items evaluated in the adaptation of this method were: setting choice, kind of milk processing and vehicles, besides material and test performance. Day hospital was considered adequate for this test. Regarding to elected materials to offer the vehicle, opaque and sealed recipients showed more suitable to test demands. Vehicles more accepted were legumes soup and soy beverage and the most adequate CM to be offered was liquid and with low lactose concentration. The difficult observed in performance of DBPCFC do not compromise its execution, however the interpretation of the results was very difficult specially in patients with perioral wheals and unspecific clinical findings. There is an agreement Comparing adopted clinical and laboratorial criterion for definition of group 1 and 2 with DBPCFC results. In conclusion, the test proved to be feasible and safe and its adaptation is possible for IgE mediated CMA diagnosis, being necessary to evaluate its reproducibility in other populations.
8

Kravské mléko jako přirozený zdroj jodu v lidské výživě / COWS MILK AS A NATURAL SOURCE OF IODINE IN HUMAN NUTRITION

VÍTKOVÁ, Lucie January 2014 (has links)
This thesis deals with the importance of milk as a natural source of iodine in human nutrition. The thesis provides a data of the consumption of milk and milk products and their contribution to the protection needs iodine for students and employees of the University of South Bohemia in Ceske Budejovice. The experiment includes a total of 60 people (20 men and 40 women). Empirical data wasobtained within the grant project named GAJU 011/2013/Z and NAZV QH 81105. Data of consumption of milk and milk products were obtained through questionnaires. For men, average weekly consumption of milk was 826.5? 835.1 ml (118.1 ml per day) and for women 912.4? 783.9 ml (130.3 ml per day). Average consumption of yogurt for men was 361.0? 401.4 g per week (51.6 g per day), for woman 428.4? 338.8 g per week (61.2 g per day) and average consuption of cheese was for men 263.0? 240.5 g per week (37.6 g per day) and for woman was 260.2? 226.5 per week (37.2 g per day). Through the milk and milk products tested, men average 81.6 g of iodine per day, woman adopted 93.4 g. According to the results, the amout of consumed milk and milk products was lower than the nationwide average, but still covered more than half of daily iodine needs. The thesis presents the data of the iodine concentration in urine for students and employees of the University of South Bohemia in Ceske Budejovice (n=62) as an indicator of iodine supply to the organism. The average iodine content in urine of all subjects (men and women) was 230.4? 171.3 gl-1, for men (n=21) reached 244.6? 195.2 gl-1, for women was 223.2? 159.8 gl-1. Results of the average iodine content in urine reflected the physiological range, i.e. for the students and employees of the University of South Bohemia was supply of iodine in organism sufficient. The thesis also provides information about the amount of iodine in asamples of cow´s milk on a selected farm (n=50) of the Jihocesky region, the Plzensky region and Vysocina during the years 2011 - 2013. Samples of cow´s milk were obtained in collaboration with the Central Laboratory of dairy Madeta a.s in Ceske Budejovice and Veterinary Centre s.r.o Susice. In 2011, the average concentration of iodine was 321,0? 337.8 gl-1, in 2012 was concentration of iodine 298.8? 290.8 gl-1 and in 2013 was 234.7? 116.1 gl-1 also otherwise: in all years was it was determined that there was an abundance of iodine. The highest values (315.6? 305.1 gl-1) of iodine was in the Jihocesky region. In Vysocina a lower average level of the iodine was detected (9.5 %), as well as in the Plzensky region where the amount of iodine in milk was lower by 53.7 %, compared to the South Bohemia region and 48.8 % compared to the Vysocina region.
9

Estimation of genetic parameters for fertility traits and the effect of milk production on reproduction performance in South African Holstein cows

Potgieter, Johannes Phillipus 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Profitable milk production and genetic improvement in dairy herds are largely dependant on fertile cows capable of calving down on an annual basis. Several studies indicate declines in the reproductive performance of Holstein cows over the last 30 years. Calving interval (CI) and services per conception (SPC) are being used by dairy farmers as indicators of the reproductive performance of dairy cows. However, using these traits as cow fertility indicators is problematic as CI is dependent on subsequent calving dates while SPC is strongly linked to inseminator proficiency. The aim of the study is therefore, firstly, to describe alternative fertility traits derived from insemination and calving dates and pregnancy check results. The effects of some non-genetic factors on these traits are discussed. Means±sd for interval traits from calving to first insemination (CFS) and the interval from calving to conception (DO) were respectively 77±30 and 134±74 days while the number of services per conception (SPC) averaged 2.55±1.79. The percentage of first servics occurring within 80 days post-partum (FS80d) and the proportion of cows being confirmed pregnant within 100 (PD100d) and 200 days post-partum (PD200d) were 0.64±0.48, 0.36±0.48 and 0.71±0.45, respectively. Although fertility traits were affected significantly by lactation number, calving year and month, herds (managers) had the largest effect. Fertility is a complex trait, however, the challenge is finding traits that best describe this trait. Genetic parameters for these traits could give an indication of the response to selection in dairy herds. In the second part of this study, genetic parameters and correlations between fertility traits, sourced from standard reproduction management data bases, are analysed for Holstein cows using bivariate linearlinear and linear-threshold animal models. Insemination events (n = 69 181) from 26 645 lactations of 9 046 Holstein cows from 14 herds, calving down during the period from 1991 to 2007, were available. The outcome of each AI event was known. Insemination records were linked to the calving date of each cow, lactation number as well as dam and sire identification. Fertility traits indicating the ability of cows to show heat early in the breeding period, and to become pregnant, were derived. Data were analysed using bivariate linear-linear and linear-threshold animal models with fixed effects being herd (14 levels), year (17 levels), season (4 levels) and lactation number (6 levels). The model included the random effects of animal and animal permanent environment (PE). Heritability estimates ranged from 0.04±0.01 to 0.10±0.02 for FS80d, from 0.07±0.01 to 0.08±0.02 for PD100d and from 0.06±0.04 to 0.08±0.02 for PD200d depending on the two-trait combination. Although heritability estimates of most fertility traits were below 0.10, they were in close agreement with results published by other researchers using linear models. Genetic correlations between different fertility parameters analyzed in this study indicated that it is unlikely that a single characteristic would serve well for selection purposes; instead, combining different traits could be used in selection programmes to improve fertility. Further research in constructing an optimal fertility index is warranted. In the third part of this study, genetic parameters for South African Holstein cows for fertility and production traits were estimated from 2415 lactation records. Two-trait analysis of fertility and milk yield was investigated as a method to estimate fertility breeding values when culling, or selection based on milk yield in early lactation, determines presence or absence of fertility observations in later lactations. Fertility traits were days from calving to first service (CFS), days from calving to conception (DO), percentage cows inseminated within 80d post-partum (FS80d), number of service per conception (SPC), and the binary traits percentage of cows pregnant within 100d and 200d postpartum (PD100d, Pd200d). Milk production traits were 300 day milk, fat and protein yield. For fertility traits, range of estimates of heritability (h2) was 0.006 to 0.08 for linear traits and 0.05 to 0.12 for binary traits. The range for permanent environmental variance (c2) was 0.016 to 0.032. In this study genetic correlations of fertility with milk production traits were unfavourable ranging between −0.93 to 0.76. / AFRIKAANSE OPSOMMING: Winsgewende melkproduksie en genetiese verbetering in melkkuddes hang grootliks af van vrugbare koeie wat op ‘n jaarlikse basis kalf. Verskeie studies toon dat die reproduksievermoë van Holsteinkoeie oor die afgelope 30 jaar afgeneem het. Melkboere gebruik tussenkalfperiode (TKP) en aantal inseminasies per konsepsie (KIPK) as aanduidings van die reproduksievermoë van melkkoeie. Dit is egter moeilik om hierdie eienskappe as vrugbaarheidseienskappe vir melkkoeie te gebruik omdat TKP afhanklik is van opeenvolgende kalfdatums terwyl KIPK baie sterk gekoppel is aan die inseminasievermoë van die insemineerders. In die eerste gedeelte van die studie word alternatiewe vrugbaarheidseienskappe, wat afgelei is van inseminasie- en kalfdatums en die uitslag van dragtigheidsondersoeke, beskryf. Die invloed van ‘n aantal nie-genetiese faktore op dié eienskappe word ook bespreek. Gemiddeldes±standaard afwykings vir die periode vanaf kalwing tot eerste inseminasie (CFS), die periode van kalwing tot konsepsie (DO) was 77±30 en 134±74 dae onderskeidelik, terwyl die aantal inseminasies per konsepsie (SPC) 2.55±1.79 was. Die persentasie eerste inseminasies wat binne 80 dae na kalwing (FS80d), en die persentasie koeie wat dragtig bevestig is binne 100 (PD100d) en 200 dae na kalwing (PD200d) was 0.64±0.48, 0.36±0.48 en 0.71±0.45, onderskeidelik. Hoewel vrugbaarheidseienskappe betekenisvol beïnvloed is deur laktasienommer, jaar en seisoen van kalwing, het kuddes (bestuurders) die grootste effek op eienskappe gehad. Vrugbaarheid is ‘n ingewikkelde eienskap en die uitdaging is om eienskappe te vind wat dit die beste beskryf. Genetiese parameters vir eienskappe wat oorweeg word sal ‘n aanduiding gee van die seleksieresponse in melkkuddes. In die tweede gedeelte van die studie is genetiese parameters van vrugbaarheidseienskappe en korrelasies tussen dié eienskappe beraam. Eienskappe is bekom vanaf reproduksiebestuursprogramme wat in melkkuddes gebruik word. Al die inseminasierekords (n = 69 181) van 26 645 laktasies van 9 046 Holsteinkoeie van 14 melkkuddes wat tussen 1991 en 2007 gekalf het, was beskikbaar. Die uitslag van elke inseminasie was bekend. Inseminasierekords is met die kalfdatum, laktasienommer, identifkasienommers van die moeder en vader van elke koei, gekoppel. Vrugbaarheidseienskappe wat die vermoë van koeie aandui om vroeg na kalwing op hitte te kom en beset te raak, is verkry. Die data is ontleed deur gebruik te maak van twee-eienskap liniêreliniêr- en liniêr-drempel-diere modelle met vaste effekte kudde (14 vlakke), jaar (17 vlakke), siesoen (4 vlakke) en laktasienommer (6 vlakke). Die modelle het die ewekansige effekte van dier- en dierpermananente omgewingseffkte (PE) ingesluit. Genetiese, diere PE en residuele korrelasies is vervolgens beraam. Oorerflikhede varieer vanaf 0.04±0.01 tot 0.10±0.02 vir FS80d, vanaf 0.07±0.01 tot 0.08±0.02 vir PD100d en vanaf 0.06±0.04 tot 0.08±0.02 vir PD200d, afhangende van die tweeeienskap kombinasie. Ten spyte daarvan dat die oorerflikhede van die meeste vrugbaarseienskappe laer as 0.10 is, is die resultate in ooreenstemming met ander navorsers wat liniëre modelle gebruik het. Genetiese korrelasies tussen verskillende vrugbaarheidseienskappe toon dat daar nie enkel beste eienskap is wat vir seleksiedoeleindes gebruik kan word nie. Dit sou waarskynlik beter wees om verskillende eienskappe te kombineer om die vrugbaarheid in melkkoeie te verbeter. Verdere navorsing is nodig om ‘n optimale vrugbaarheidseienskap te ontwikkel. Dit is belangrik dat die verband tussen reproduksie en melkproduksie vir melkkoeie bepaal word. In die derde gedeelte van die studie is genetiese parameters vir vrugbaarheid- en melkproduksieeienskappe vir Suid Afrikaanse Holsteinkoeie beraam. ‘n Totaal van 2415 laktasierekords was beskikbaar. Vrugbaarheid en melkproduksie is volgens ‘n twee-eienskap analise ontleed as ‘n metode om teelwaardes vir vrugbaarheid te bepaal in gevalle waar die uitskot of seleksie gebaseer op melkproduksie in vroeglaktasie die teenwoordigheid of afwesigheid van vrugbaarheidseienskappe in latere laktasies bepaal. Vrugbaarheidseienskappe was die periode (aantal dae) tussen kalfdatum en eerste inseminasie (CFS), die aantal dae van kalf tot konsepsie (DO), die persentasie koeie wat by 80 dae na kalf vir die eerste keer geïnsemineer was (FS80d), die aantal inseminasies per konsepsie (SPC), en binêre eienskappe van die persentasie koeie wat by 100 dae en 200 dae na kalf beset was (PD100d en PD200d). Melkproduksie-eienskappe was 300-dae melk., vet- en proteïnproduksie. Vir vrugbaarheidseienskappe het die oorerflikheidswaardes (h2) vanaf 0.006 tot 0.08 vir liniêre eienskappe gevarieer en tussen 0.05 tot 0.12 vir binêre eienskappe. Die permanente omgewingsvariansie (c2) het tussen 0.016 tot 0.032 gevarieer. In hierdie studie was die genetiese korrelasies tussen vrugbaarheidseienskappe en melkproduksie-eienskappe ongunstig en het dit tussen −0.93 tot 0.76 gevarieer.
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Reatividade a múltiplas proteínas da dieta em crianças com alergia ao leite de vaca mediada pela imunoglobulina E / Reactivity to multiple protein diet in children with cow\'s milk allergy mediated by immunoglobulin E

Paschoal, Patricia Olaya 01 November 2011 (has links)
Objetivos: Determinar a reatividade dos soros e determinação dos isotipos IgG e IgE a proteínas de sementes da dieta de crianças com alergia ao leite de vaca IgE mediada. Métodos: Foram avaliados soros de três grupos de crianças: alérgicas ao leite de vaca IgE mediada, crianças tolerantes ao leite e um grupo controle com crianças não atópicas. Foram usados extratos protéicos de diferentes tipos de sementes utilizando o teste de ELISA para análise da reatividade dos isotipos IgG e IgE. Resultados: Comparando as concentrações séricas de IgG dos diferentes grupos, observou-se concentrações mais elevadas e estatisticamente significante no grupo alérgico em relação aos grupos tolerante e controle, exceto para as sementes de soja e feijão roxinho. Em relação ao isotipo IgE observou-se os mesmos padrões de reatividade mostradas nas analises para IgG, com diferença significante do grupo alérgico em relação ao controle, exceto para milho. Observou-se que para a soja houve grande dispersão das concentrações séricas tanto no grupo alérgico quanto no tolerante, em valores superiores ao do grupo controle. Conclusão: A comparação entre os diversos grupos avaliados mostra que pacientes alérgicos ao leite e os tolerantes apresentam concentrações mais elevadas de IgG e IgE a outros alimentos que as crianças do grupo controle, o que pode sugerir possível alteração de permeabilidade da mucosa intestinal nestes grupos, mesmo na ausência de sintomatologia gastrintestinal / Objective: To determine the reactivity of serum and determination of IgG and IgE isotypes to seed proteins included in the diet of children with cow\'s milk allergy IgE mediated. Methods: We evaluated sera from three groups of children: cow\'s milk allergic patients, tolerant children and a control group with non-atopic children. It was used protein extracts from different types of seeds using an ELISA assay to analyze the reactivity of IgG and IgE isotypes. Results: Comparing the IgG serum from different groups, it was observed higher concentrations and statistically significant in the allergic group compared to the tolerant and control groups, except for soybeans and kidney beans. To the IgE isotype it was observed the same patterns of reactivity shown in the analysis for IgG, with significant difference in the allergic group compared to control, except for corn. It was observed that for soybeans there were values of serum, both in the allergic and tolerant group higher than in the control group. Conclusion: Our study showed that the allergic and tolerant groups of CMA patients presented higher IgG and IgE concentrations to many seeds than the control group. These findings may suggest possible changes in permeability intestinal mucosa in these groups

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