bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Pediatric Rome III Criteria of Functional Dyspepsia on the Diagnostic Yield of Upper Endoscopy and Predictors for a Positive Endoscopic Finding
Authors: Tam Yuk Him , Chan Kin Wai , To Ka Fai , Cheung Sing Tak , Mou Jennifer Wai Cheung , Pang Kristine Kit Yi , Wong Yuen Shan , Sihoe Jennifer Dart Yin , Lee Kim Hung
Published: March 2011

Objective:

Pediatric Rome III criteria of functional dyspepsia (FD) has eliminated the mandatory use of upper endoscopy and recommended a symptom‐based approach. In the absence of alarm symptoms, FD can be positively diagnosed in children having normal physical findings without exclusionary investigations. We aimed to investigate the effectiveness of Rome III guidelines to discriminate organic diseases from FD and to identify the predictors for positive endoscopic findings.

Patients and Methods:

A prospective study was conducted on consecutive children fulfilling Rome III criteria of FD. Upper endoscopy was performed in all subjects, both with and without alarm features.

Results:

Eighty consecutive children ages 7 to 15 were recruited. Nine (11.3%) had experienced alarm features. Five (6.3%) had organic diseases confirmed in upper endoscopy: duodenal ulcer (n = 2), duodenitis with erosion (n = 2), and gastritis with erosion (n = 1), 33.3% of children having alarm features had organic pathology, compared with 2.8% of those without (P < 0.01). A male predominance (80% vs 25.3%, P < 0.01), higher prevalence of alarm features (60% vs 8%, P < 0.01), and higher prevalence of Helicobacter pylori infection (80% vs 5.3%, P < 0.01) were found in children with organic diseases, compared with FD. Multivariate analysis identified H pylori infection (odds ratio 23.2; 95% confidence interval 1.5–333) and nocturnal pain (odds ratio 26.3; 95% confidence interval 1.2–500) to be independent predictors for positive endoscopic findings.

Conclusions:

Rome III recommendations of screening dyspeptic children for alarm features and investigation for H pylori are effective to identify children who have a higher likelihood of organic diseases and require upper endoscopy before making a diagnosis of FD.
Socio‐demographic factors influence the attitudes of local residents towards trophy hunting activities in the Kilombero Valley, Tanzania
Authors: Jew Eleanor , Bonnington Colin
Published: March 2011

Within the Kilombero Game Controlled Area (KGCA) of Tanzania, protection is offered to large mammal populations by trophy hunting concessions that maintain natural habitat through the prevention of extensive human encroachment. The opinions of local communities to wildlife management operations such as trophy hunting play an important role in their long‐term viability. This study addresses the influence of socio‐demographic factors on the opinions of local communities to trophy hunting in areas that are not part of community‐based management projects, which is where most research of this type has previously been conducted. Semi‐structured questionnaires were conducted in 24 villages within the Kilombero Valley (fifteen interviews per village) in August–December 2007. The extent to which socio‐demographic factors including location (e.g. village of residence) and individual respondent characteristics (e.g. gender and age) influenced the respondents’ opinions was analysed. Of these socio‐demographic factors, all, except age and district of residence, were found to influence the opinions of local residents.

Socio‐demographic factors play an important role in determining local communities’ attitudes towards trophy hunting, and this must be taken into account during the design and assessment of wildlife management conservation strategies, both locally in the KGCA and in similar national and international initiatives.
Efficacy and safety of home-based subcutaneous immunoglobulin replacement therapy in paediatric patients with primary immunodeficiencies
Authors:   Vivaglobin Study Group, Borte M , Bernatowska E , Ochs H D , Roifman C M
Published: March 2011

Subcutaneous immunoglobulin infusions are effective, safe and well tolerated in the treatment of primary immunodeficiencies, but only limited data on the treatment of children are available. We investigated the efficacy, safety and pharmacokinetics of home therapy with a 16% liquid human immunoglobulin G preparation (Vivaglobin®) when administered subcutaneously in children with primary immunodeficiencies. Data were analysed from 22 children (2–<12 years) who participated in two prospective, open-label studies (one in Europe/Brazil, one in North America). All children had previously received intravenous immunoglobulins. They started weekly subcutaneous immunoglobulin infusions with an approximately 3-month wash-in/wash-out period, followed by a 6-month (Europe/Brazil) or 12-month (North America) efficacy evaluation period. In Europe/Brazil, subcutaneous doses generally equalled the previous weekly equivalent intravenous doses. In North America, subcutaneous doses during the efficacy evaluation period were 126% (median) of the previous weekly equivalent intravenous doses. Efficacy end-points in both studies included the occurrence of serious bacterial infections and any infections, and serum immunoglobulin G trough levels. Median serum immunoglobulin G trough levels exceeded those during previous intravenous therapy by 13% (North America) and 16% (Europe/Brazil). During the efficacy evaluation period of both studies, none of the children had a serious bacterial infection; the mean overall infection rate/patient year was 4·7 in Europe/Brazil and 5·6 in North America, concurring with previous reports in adults. The adverse event profile was comparable to previous reports in adults. Both studies confirmed the efficacy and safety of subcutaneous immunoglobulin therapy with Vivaglobin in children with primary immunodeficiencies.
Kin structure and genotype‐dependent mortality: a study using the neotropical tree Caryocar brasiliense
Authors: Collevatti Rosane G. , Hay John D.
Published: March 2011

1. In many species, density‐dependent processes regulate population size through size‐ and neighbourhood‐dependent mortality.

2. If a kin structure exists in a particular population, mortality may be spatially clustered due to enhanced competition among relatives.

3. Demography, kin structure and genetic diversity, based on 10 microsatellite loci, of a local population of the Neotropical tree Caryocar brasiliense were studied for 23 years. Overall population growth was static (λ = 1.0) during this time, but some time intervals showed negative growth.

4. Mortality was spatially clustered and negatively correlated with spatial distance among pairs of individuals at distances lower than c. 13 m. Probability of death was related to individual genotypes, and seedlings and juveniles with lower proportion of heterozygous loci had the highest probability of mortality.

5. Kinship was significantly related to spatial distance among pairs of individuals at distance lower than 10 m and kinship structure did not change along the life stages, but the inbreeding coefficient was not significantly different from zero in adults.

6. Synthesis. We hypothesize that genetic clustering in C. brasiliense dissipates over time due to more intense competition among relatives. Thus, the kin structure in C. brasiliense is highly important in determining mortality patterns, driving the spatial pattern in plant recruitment.
Heterozygosity–fitness correlations among wild populations of European tree frog (Hyla arborea) detect fixation load
Authors: LUQUET E. , DAVID P. , LENA J.‐P. , JOLY P. , KONECNY L. , DUFRESNES C. , PERRIN N. , PLENET S.
Published: March 2011

Quantifying the impacts of inbreeding and genetic drift on fitness traits in fragmented populations is becoming a major goal in conservation biology. Such impacts occur at different levels and involve different sets of loci. Genetic drift randomly fixes slightly deleterious alleles leading to different fixation load among populations. By contrast, inbreeding depression arises from highly deleterious alleles in segregation within a population and creates variation among individuals. A popular approach is to measure correlations between molecular variation and phenotypic performances. This approach has been mainly used at the individual level to detect inbreeding depression within populations and sometimes at the population level but without consideration about the genetic processes measured. For the first time, we used in this study a molecular approach considering both the interpopulation and intrapopulation level to discriminate the relative importance of inbreeding depression vs. fixation load in isolated and non‐fragmented populations of European tree frog (Hyla arborea), complemented with interpopulational crosses. We demonstrated that the positive correlations observed between genetic heterozygosity and larval performances on merged data were mainly caused by co‐variations in genetic diversity and fixation load among populations rather than by inbreeding depression and segregating deleterious alleles within populations. Such a method is highly relevant in a conservation perspective because, depending on how populations lose fitness (inbreeding vs. fixation load), specific management actions may be designed to improve the persistence of populations.
Expression of the ompATb operon accelerates ammonia secretion and adaptation of Mycobacterium tuberculosis to acidic environments
Authors: Song Houhui , Huff Jason , Janik Katharine , Walter Kerstin , Keller Christine , Ehlers Stefan , Bossmann Stefan H. , Niederweis Michael
Published: March 2011

Homeostasis of intracellular pH is a trait critical for survival of Mycobacterium tuberculosis in macrophages. However, mechanisms by which M. tuberculosis adapts to acidic environments are poorly understood. In this study, we analysed the physiological functions of OmpATb, a surface‐accessible protein of M. tuberculosis. OmpATb did not complement the permeability defects of a Mycobacterium smegmatis porin mutant to glucose, serine and glycerol, in contrast to the porin MspA. Uptake rates of these solutes were unchanged in an ompATb operon mutant of M. tuberculosis indicating that OmpATb is not a general porin. Chemical analysis of low‐pH culture filtrates showed that the proteins encoded by the ompATb operon are involved in generating a rapid ammonia burst, which neutralized medium pH and preceded exponential growth of M. tuberculosis. Addition of ammonia accelerated growth of the ompATb operon mutant demonstrating that ammonia secretion is indeed a mechanism by which M. tuberculosis neutralizes acidic environments. Infection experiments revealed that the ompATb operon was not required for full virulence in mice suggesting that M. tuberculosis has multiple mechanisms of resisting phagosomal acidification. Taken together, these results show that the ompATb operon is necessary for rapid ammonia secretion and adaptation of M. tuberculosis to acidic environments in vitro but not in mice.
Effect of GABA‐ergic mechanisms on synaptosomal NO synthesis and the nitrergic component of NANC relaxation in rat ileum
Authors: Kurjak M. , Fichna J. , Harbarth J. , Sennefelder A. , Allescher H. D. , Schusdziarra V. , Storr M. , Otto B.
Published: March 2011

Background  γ‐Aminobutyric acid (GABA) acts on specific neural receptors [A, B and C(Aρ)] to modulate gastrointestinal function. The precise role of GABA receptor activation in the regulation of presynaptic nitric oxide (NO) synthesis in nerve terminals is unknown.

Methods  Rat ileal nerve terminals were isolated by differential centrifugation. Nitric oxide synthesis was analysed using a L‐[3H]arginine assay. In vitro studies were performed under non‐adrenergic non‐cholinergic (NANC) conditions on isolated ileal segments.

Key Results  γ‐Aminobutyric acid inhibited NO synthesis significantly (n = 6, P < 0.05) [(fmol mg−1 min−1) control: 27.7 ± 1.5, 10−6 mol L−1: 19.7 ± 1.3; 10−5 mol L−1: 17.5 ± 3.0]. This effect was antagonized by the GABA A receptor antagonist bicuculline and the GABA C receptor antagonist (1,2,5,6‐tetrahydropyridin‐4‐yl)methylphosphinic acid (TPMPA), but not by the GABA B receptor antagonist SCH 50911. The GABA A receptor agonist muscimol [(fmol mg−1 min−1) control: 27.6 ± 1.0, 10−6 mol L−1: 19.1 ± 1.7, n = 5, P < 0.05] and the GABA C receptor agonist cis‐4‐aminocrotonic acid (CACA) [(fmol mg−1 min−1) control: 29.5 ± 3.2, 10−3 mol L−1: 20.3 ± 2.5, n = 6, P < 0.05], mimicked the GABA‐effect, whereas the GABA B agonist baclofen was ineffective. Bicuculline reversed the inhibitory effect of muscimol, TPMPA antagonized the effect of CACA. In functional experiments the GABA A and C receptor agonists reduced the NANC relaxation induced by electrical field stimulation in rat ileum by about 40%. After NOS‐inhibition by Nε‐nitro‐l‐arginine methyl ester (l‐NAME) the GABA A receptor agonist had no effect, whereas the GABA C receptor agonist still showed a residual response.

Conclusions & Inferences  γ‐Aminobutyric acid inhibits neural NO synthesis in rat ileum by GABA A and GABA C(Aρ) receptor‐mediated mechanisms.
Contrasting growth and adaptive responses of two oak species to flooding stress: role of non‐symbiotic haemoglobin
Authors: PARENT CLAIRE , CRÈVECOEUR MICHÈLE , CAPELLI NICOLAS , DAT JAMES F.
Published: March 2011

Soil flooding is an environmental constraint that is increasingly important for forest ecosystems, affecting tree growth and regeneration. As a result, selection pressure will alter forest diversity and distribution by favouring tree species tolerant of soil oxygen deprivation. Sessile and pedunculate oaks are the most abundant oak species and they exhibit a strong differential tolerance to waterlogging. In order to gain some understanding of the mechanisms of tolerance of both species to hypoxia, we undertook the characterization of the physiological, morphological, cellular and molecular responses of both species to flooding stress. Our results indicate that pedunculate oak, the more tolerant species, succeeded in maintaining its growth, water status and photosynthetic activity at a higher level than sessile oak. Furthermore, pedunculate oak developed aerenchyma in its root cortex as well as adventitious roots. The later exhibited a strong accumulation of class1 non‐symbiotic haemoglobin localized by in situ hybridization in the protoderm and in some cortical cells. In conclusion, the higher tolerance of pedunculate oak to flooding was associated with an enhanced capacity to maintain photosynthesis and water homeostasis, coupled with the development of adaptive features (aerenchyma, adventitious roots) and with a higher expression of non‐symbiotic haemoglobin in the roots.
The OzT8 locus in rice protects leaf carbon assimilation rate and photosynthetic capacity under ozone stress
Authors: CHEN CHARLES P. , FREI MICHAEL , WISSUWA MATTHIAS
Published: March 2011

Tropospheric ozone (O3) is a phytotoxic air pollutant whose current background concentrations in parts of East Asia have caused estimated rice yield losses of up to 20%; currently, however, little is known about the mechanisms of O3 tolerance in rice. We previously identified a quantitative trait locus (QTL) in rice called OzT8, which was associated with relative dry weight under ozone stress. The photosynthetic response in SL46, a Nipponbare (NB)–Kasalath chromosome segment substitution line (SL) containing the OzT8 locus, was compared to the parent NB in multiple ozone fumigation experiments (100 ppb, 8 h d–1, 23 d). By day 23, SL46 showed significantly less reduction of photosynthetic capacity compared to NB; the maximum carboxylation rate of ribulose 1·5‐bisphosphate carboxylase/oxygenase (Rubisco) decreased by 24% in SL46 compared to 49% in NB, and the maximum electron transport rate decreased by 16 and 39%, respectively. The midday carbon assimilation rates also showed a similar trend, but there was no genotypic difference in stomatal conductance. These results indicate that the OzT8 locus confers ozone tolerance via biochemical acclimation, not avoidance, making it a potentially valuable target for breeding of ozone tolerance into future rice lines. The sequence of photosynthetic response of rice to ozone stress and related tolerance factors are also discussed.
Genetic dissection of basal defence responsiveness in accessions of Arabidopsis thaliana
Authors: AHMAD SHAKOOR , VAN HULTEN MARIEKE , MARTIN JANET , PIETERSE CORNÉ M. J. , VAN WEES SASKIA C. M. , TON JURRIAAN
Published: March 2011

Basal resistance involves a multitude of pathogen‐ and herbivore‐inducible defence mechanisms, ranging from localized callose deposition to systemic defence gene induction by salicylic acid (SA) and jasmonic acid (JA). In this study, we have explored and dissected genetic variation in the responsiveness of basal defence mechanisms within a selection of Arabidopsis accessions. Responsiveness of JA‐induced PDF1.2 gene expression was associated with enhanced basal resistance against the necrotrophic fungus Plectosphaerella cucumerina and the herbivore Spodoptera littoralis. Conversely, accessions showing augmented PR‐1 induction upon SA treatment were more resistant to the hemi‐biotrophic pathogen Pseudomonas syringae, and constitutively expressed defence‐related transcription factor (TF) genes. Unexpectedly, accessions with primed responsiveness to SA deposited comparatively little callose after treatment with microbe‐associated molecular patterns. A quantitative trait locus (QTL) analysis identified two loci regulating flagellin‐induced callose and one locus regulating SA‐induced PR‐1 expression. The latter QTL was found to contribute to basal resistance against P. syringae. None of the defence regulatory QTLs influenced plant growth, suggesting that the constitutive defence priming conferred by these loci is not associated with major costs on plant growth. Our study demonstrates that natural variation in basal resistance can be exploited to identify genetic loci that prime the plant's basal defence arsenal.
Portrayal of organ donation and transplantation on American primetime television
Authors: Harbaugh Calista , Afana Majed , Burdick Stephanie , East Joseph , Kodali Sindhura , Lee Jay , Patel Shaun , Rangrass Govind , Ranney David , Sood Vikram , Lynch Raymond , Sonnenday Christopher J. , Englesbe Michael J. , Mathur Amit K.
Published: March 2011

Harbaugh C, Afana M, Burdick S, East J, Kodali S, Lee J, Patel S, Rangrass G, Ranney D, Sood V, Lynch R, Sonnenday CJ, Englesbe MJ, Mathur AK. Portrayal of organ donation and transplantation on American primetime television. Clin Transplant 2011: 25: E375–E380. © 2011 John Wiley & Sons A/S.

Abstract:  Recently, both living and deceased organ donation rates have hit a plateau, despite increases in need for viable organs. One approach to improve donation rate is public education and policy; thus, it is necessary to understand the information the public is receiving regarding organ donation. We hypothesized that primetime medical dramas portray organ donation and transplantation in a negative manner. We compiled data on all primetime medical drama episodes with transplant themes from November 2008 through June 2010 and assessed depictions of organ donors and transplant candidates. Positive and negative thematic elements surrounding the process and individuals involved were also identified. One hundred and fifty‐five million and 145 million households watched episodes containing any negative message and any positive message, respectively. Episodes containing only negative messages had over twice the household viewership per episode compared to episodes containing only positive messages (8.4 million vs. 4.1 million, p = 0.01). Widespread exposure to these representations may reinforce public misconceptions of transplantation. The transplant community should consider the popularity of medical dramas as an opportunity to impact the perception of organ donation and transplantation for millions of Americans.
A novel HLA‐DRB4 allele, DRB4*01:08, identified by sequence‐based typing
Authors: Lee E. , Ozaki S. , Ishii H. , Takimoto T. , Matsumoto T.
Published: March 2011

New allele DRB4*01:08 showed one nucleotide difference with DRB4*01:01:01:01 at codon 87 (GAG>AAG).
Alternatives to least squares in multiple linear regression to predict production traits
Authors: Bergmann J. A. G. , Hohenboken W. D.
Published: March 2011

The objectives of this study were to describe and compare the efficacy of least‐squares, ridge‐and principal‐components‐regression methodology for analysis of data for which multicollinearity existed among regressor variables. A data set composed of calfhood traits (regressor variables) and first‐progeny weaning weight (the dependent variable) of 771 Angus females was used. The statistics variance‐inflation factors, eigenvalues, condition numbers and variance proportions were used in diagnosing multicollinearity. Although biased, the regression‐coefficient estimates produced by ridge and principal components regression had smaller variances than estimates obtained from least squares.

Between the two alternatives to least squares, ridge regression produced better results than principal‐components regression. Ridge and least‐squares regression produced similar regression‐coefficient estimates, prediction sum of squares (PRESS‐like) statistics and, to a lesser extent, conceptual predictive criteria (Cp‐like) statistics. For prediction, the performance of least‐squares and ridge‐regression models was very similar.

Alternativen zu Minimum‐Quadrat bei multipler linearer Regression zur Voraussage von Leistungsmerkmalen

Die Untersuchung bezieht auf Beschreibung und Vergleich der Wirksamkeit von Minimum‐Quadrat, Ridge und Hauptkomponentenregressionsmethodik zur Analyse von Daten mit Multicollinearität zwischen Regressorvariablen. Das Datenmaterial aus Kälberleistungen (Regressorvariable) und Absatzgewicht der ersten Nachkommen (abhängige Variable) von 771 Anguskühen wurde verwendet. Die statistischen Größen Varianz inflationsfaktoren, Eigenwerte, Bedingungszahl und Varianzverhältnisse wurden zur Diagnose der Multicollinearität verwendet. Obwohl verzerrt, haben die Regressionskoeffizientenschätzungen aus Ridge‐und Hauptkomponentenregression geringere Varianzen als Minimum‐Quadratschätzungen. Von den zwei Alternativen hat Ridge‐Regression bessere Resultate als Hauptkomponentenregression ergeben. Ridge und Miniumum‐Quadratregression haben ähnliche Regressionskoeffizienten ergeben, Schätzungsquadratsumme (PRESS‐ähnlich), Statistik und, in einem geringeren Ausmaß, Schätzungskriterien (Cp‐ähnliche)‐statistik. Im Hinblich auf Voraussage war die Leistung der Minimum‐Quadrat‐und Ridge‐Regressions‐Modelle sehr änlich.
Genetic parameters for reproduction traits in sows and relations to performance‐test measurements
Authors: Rydhmer L. , Lundeheim N. , Johansson K.
Published: March 2011

Multivariate REML (Restricted Maximum Likelihood) analysis was used to estimate genetic parameters for 4068 Swedish Yorkshire sows from nucleus herds. Heritabilities were estimated to be 0.27, 0.13, 0.08 and 0.12 for age at first farrowing, number of piglets born alive in the first litter, length of the first farrowing interval, and number of piglets born alive in the second litter, respectively. Month of first farrowing had a significant effect on age at first farrowing and length of the first‐farrowing interval. The genetic correlation between litter size in the first litter and that in the second litter was 0.67, and the corresponding environmental correlation was 0.09. There was a significant negative genetic correlation between growth rate during the performance test and age at first farrowing. The genetic correlation between backfat thickness at the end of performance test and age at first farrowing also tended to be negative. No significant correlations between either of the two production traits and litter size at birth were found.

Genetische Parameter für Fruchtbarkeitsmerkmale von Sauen und Beziehungen zu Mastleistungsmerkmalen

Multivariate REML Analyse wurde zur Schätzung genetischer Parameter an Datenmaterial von 4068 Schwedischen Yorkshire Sauen angewendet. Heritabilitätswerte für Erstferkelalter, Zahl lebendgeborener Ferkel im ersten Wurf und zweiten Wurf und Zwischenwurfintervall waren 0,27, 0,13, 0,12 und 0,08. Monat des Erstwurfes zeigte signifikanten Einfluß auf Erstwurfalter und Zwischen‐wurfzeit. Die genetische Korrelation zwischen Wurfgrößen 1 und 2 was 0,67, die umweltbedingte 0,09. Zwischen Zuwachs im Prüfabschnitt und Erstwurfalter existiert eine signifikante negative genetische korrelation, während die zwischen Rückenspeckdicke und Erstwurfalter dahin tendiert. Wurfgröße ist aber mit keinem der beiden Mastleistungsmerkmale signifikant korreliert.
Genetic parameters for milk yield in dairy sheep
Authors: Carriedo J. A. , Baro J. A. , Fuente L. F. de la , Primitivo F. san
Published: March 2011

A repeatability animal model and restricted‐maximum‐likelihood methods were used to estimate genetic parameters of milk yield in dairy sheep. A total of 14 388 lactation records of 4123 ewes from three Churra flocks with full pedigree information for many years were considered. The following estimates were obtained for each flock: repeatability: 0.43, 0.32, and 0.32; percentage of permanent environmental variance: 14.3%, 17.3%, and 16.8%; heritability: 0.29, 0.15, and 0.15; coefficient of additive genetic variation: 13.6%, 11.8%, and 11.2%. When the additive genetic variation coefficient is taken into consideration, the estimates obtained could allow one to expect that the response to selection using a repeatability model for dairy‐sheep‐breeding programmes may be relatively high.

Genetische Parameter für Milchleistung von Schafen

Ein Wiederholbarkeits‐Tiermodell und restringierte Maximum‐Likelihood‐Methoden wurden zur Schätzung genetischer Parameter für Milchmenge in Schafen verwendet. Insgesamt 14 388 Laktationen von 4123 Mutterschafen von 3 Churra‐Herden mit voller Pedigreeinformation über mehrere Jahre wurden analysiert. Folgende Schätzwerte wurden für die einzelnen Herden erhalten: Wiederholbarkeit 0,43, 0,32 und 0,32; Anteil permanenter Umweltvarianz 14,3, 17,3 und 16,8%; Heritabilität 0,29, 0,15 und 0,15; genetischer Variationskoeffizient 13,6, 11,8 und 11,2%.

Im Hinblick auf die genetischen Variantionskoeffizienten sollte der Selektionserfolg bei Verwendung eines Wiederholbarkeitsmodells für Milchschaf günstig sein.

Parámetros genéticos para la producción láctea del ganado ovino lechero

Un modelo animal de repetibilidad y el método de máxima versimilitud restringida fueron usados para estimar los parámetros genéticos de la produccoión láctea en el ganado ovino lechero. Se consideraron 14 388 lactaciones de 4123 ovejas de tres rebaños de raza Churra con información de pedigree completa para muchos años. Fueron obtenidas las siguientes estimas para cada rebaño: repetibilidad: 0.43, 0.32, y 0.32; porcentage de varianza del ambiente permanente: 14.3, 17.3, 16.8%; heredaibilidad: 0.29, 0.15, 0.15; coeficiente de variación genético aditivo: 13.6, 11.8, 11.2%. Tomando en consideración el coeficiente de variación genético aditivo, las estimaciones obtenidas nos permitirían esperar que la respuesta a selección del ganado ovino lechero puede ser relativamente grande.
Sequence variation in the ovine cytochrome‐b gene
Authors: Hiendleder S.
Published: March 2011

The complete mitochondrial cytochrome b sequences of two Merinolandschaf individuals, preselected for mtDNA divergence on the basis of RFLP data, were determined and compared with a published sequence of Ovis aries. A total of 14 variable nucleotide positions were identified, the majority of these were silent third‐position transitions. Sequence differences ranged from 0.18% to 1.23%. A total of three variable residues (Ala/Gly, Ile/Val) in the predicted amino‐acid sequence was detected. The replacements can be considered conservative, and are located in the transmembrane regions of the protein. An influence on electron transport is therefore unlikely, although influences on enzyme function cannot be completely ruled out.

Sequenzvariabilität im ovinen Cytochrom b Gen

Die vollständige Sequenz des mitochondrialen Cytochrom b Genes zweier Merinolandschafe, die mittels RFLP‐Analysen auf Sequenzdivergenz vorselektiert worden waren, wurde bestimmt und mit einer publizierten Ovis aries Sequenz verglichen. Insgesamt wurden 14 variable Nukleotidpositionen identifiziert. Hierbei handelte es sich überwiegend um stille Transitionen in der dritten Codonposition. Die berechneten Sequenzunterschiede betragen 0.18%‐1.23%. An drei Positionen wurden Aminosäurensubstitutionen in der abgeleiteten Sequenz ermittelt (Ala/Gly, Ile/Val). Da diese Substitutionen als konservativ angesehen werden können und sich ausnahmslos in den Transmembranregionen des Proteins befinden, ist eine Beeinflussung des Elektronentransportes eher unwahrscheinlich. Mögliche Einflüsse auf die Enzymfunktion können allerdings nicht ausgeschlossen werden.
Crossbreeding in farm animals. V. Analysis of crossbreeding plans with secondary crossbred generations
Authors: Wolf J. , Distl O. , Hyánek J. , Grosshans T. , Seeland G.
Published: March 2011

Starting with the consideration of a two‐locus system of a diploid organism, a general model for crossbreeding parameters, including additive, dominance, additive × additive, additive × dominance and dominance × dominance effects, is derived. A general procedure for the calculation of the coefficients of the crossbreeding parameters is described. As the number of parameters in the general model is high, reparametrization conditions must be introduced to reduce this number. The derivation of 13 models for two source populations known from the literature is demonstrated. Four new models for a detailed analysis of epistatic effects in crossbreeding plans with more than two source populations are presented. An example from cattle breeding is given. Problems connected with the reparametrization and the estimation of effects are discussed.

Kreuzungszucht bei Nutztieren. V. Analyse von Kreuzungsplänen mit sekundären Kreuzungsgenerationen

Ausgehend von der Betrachtung eines Zweilokus‐Systems eines diploiden Organismus wird ein allgemeines Modell für Kreuzungsparameter abgeleitet, das additive, dominante, additiv × additive, additiv × dominante und dominant × dominante Effekte enthält. Eine allgemeine Methode zur Berechnung der Koeffizienten der Kreuzungsparameter wird beschrieben. Da die Anzahl der Parameter im allgemeinen Modell hoch ist, müssen Reparametrisierungsbedingungen eingeführt werden, um diese Anzahl zu senken. Die Ableitung von 13 Modellen für zwei Ausgangspopulationen, die aus der Literatur bekannt sind, wird demonstriert. Vier neue Modelle für eine detaillierte Analyse von epistatischen Effekten in Kreuzungsplänen mit mehr als zwei Ausgangspopulationen werden vorgestellt. Ein Beispiel aus der Rinderzüchtung wird angeführt. Probleme, die mit der Reparametrisierung und der Schätzung der Effekte zusammenhängen, werden diskutiert.
Estimation of prediction‐error variances by resampling
Authors: García‐Cortés L. A. , Moreno C. , Varona L. , Altarriba J.
Published: March 2011

Two resampling procedures were used to obtain consistent estimates of the prediction‐error variances. These procedures are based on different empirical estimators of the variance of the involved variables, such as the predictors or the prediction errors. The efficiency of these procedures is analysed in single‐record animal models. To improve the efficiency in the whole parametric space, a pool of these estimators was also proposed. The correlation coefficient was 0.96 in the best of the proposed methods. Finally, a short comment is made on their efficiency in variance component estimation.

Estimatión de varianzas de error de predictión mediante remuestreo

Se han utilizado dos procedimientos para obtener estimadores consistentes de las varianzas de error de predicción Estos procedimientos se basan en distintos estimadores empíricos de las varianzas de las variables involucradas, tales como los predictores o los errores de predicción. Se analiza su eficiencia en modelos animales con un sólo registro. Se propone además una combinación de estimadores que incrementa la eficiencia en todo el espacio paramétrico. El coeficiente de correlación fue de 0.96 en el mejor de los métodos popuestos. Finalmente, se comenta de forma sucinta la eficiencia de estos procedimientos en la estimación de componentes de varianza.

Scbätzung der Fehler Varianzen für Zuchtwertvoraussage mittels wiederholter Stichprobenziehung

Konsistente Schätzungen der Inversen der Koeffizientenmatrize von Mischmodellgleichungen wurden mittels zweier Arten von Stichproben ermittelt. Diese beruhen auf verschiedenen empirischen Schätzfehlern. Die Wirksamkeit der beiden Ansätze wurden an einem Tiermodell für ein Merkmal untersucht. Kombination der Schätzer steigerte die Effizienz über den ganzen Parameterraum. Die Korrelation zwischen den besten der vorgeschlagenen Methode war 0.96. Die Wirksamkeit der Varianzkom‐ponentenschätzung wird kommentiert.
Relationship between plasma hormone and metabolite levels and breeding values of bulls1
Authors: Graml R. , Olbrich‐Bludau A. , Schwab M. , Schallenberger E. , Schams D. , Pirchner F.
Published: March 2011

Blood plasma levels of the hormones bovine growth hormone (bGH), insulin and insulin‐like growth factor 1 (IGF‐1) and the metabolites glucose, free fatty acids (FFA), urea, creatine and creatinine in 70 bulls (Fleckvieh, Braunvieh, Grauvieh) kept at four AI stations were measured. Plasma determinations were performed on day 1 with normal feeding (N), day 4 after fast (F), and day 5 (R) after realimentation. Fleckvieh bulls had lower bGH but higher IGF‐1 levels than Braunvieh bulls; young bulls had lower IGF‐1 and insulin but higher glucose levels than mature bulls. The effect of fasting led to higher plasma levels of FFA, urea and creatinine and to lower levels of bGH and IGF‐1. Correlations between plasma levels and breeding values for yield of milk, fat and protein were estimated for mature bulls. All three breeding values correlated positively with bGH and negatively with insulin, while correlations with other indicators depended on the feeding status of bulls. Prediction equations for breeding values which were limited to three indicators, included FFA, urea, and creatinine, and the r2 values ranged up to 0.32. Validation of these equations, derived from Fleckvieh bulls, on Braunvieh and Grauvieh bulls resulted in correlations of about 0.2. The use of indicators, in addition to information from relatives (dam, full and half‐sisters), improves the accuracy of selection of young bulls.

Beziehungen zwischen Plasmahormon und ‐metabolitenspiegel in Milchzuchtwerten

Von 70 Bullen der Rassen Fleckvieh, Braunvieh und Tiroler Grauvieh aus vier Besamungsstationen wurden die Blutkonzentrationen der Hormone bGH, IGF‐1 und Insulin sowie die der Metaboliten Glucose, Freie Fettsäuren (FFA), Harnstoff, Kreatin und Kreatinin während normaler Fütterung (N), nach einer Fastenperiode (F) und nach Wiederfütterung (R) bestimmt. Fleckviehbullen hatten signifikant mehr bGH und IGF‐1 als Braunviehbullen, Jungbullen signifikant weniger IGF‐1 und Insulin, aber mehr Glucose als ausgewachsene Bullen. Fasten der Tiere führte zu signifikant höherem Blutspiegel an Freien Fettsäuren, Harnstoff und Kreatin und zu niedrigerem Blutspiegel an bGH und IGF‐1. Korrelationen zwischen Blutserumspiegel und Zuchtwert für Milchmenge, Fettmenge und Proteinmenge wurden geschätzt. bGH hatte eindeutig einen positiven, Insulin einen negativen Zusammenhang zu alien Zuchtwerten, während er bei den anderen Blutparametern je nach Fütterungsstatus unterschiedlich war. Schätzungsgleichungen für Zuchtwerte aus drei Blutwerten wurden erstellt, die Freie Fettsäuren, Harnstoff und Kreatinin berücksichtigten. Validierungen der Schätzungsgleichungen für Fleckvieh an Braunvieh und Grauvieh ergaben Korrelationen von etwa 0,20. Die Wirksamkeit der Verwendung der Indikatoren zur Zuchtwertschätzung eines Jungbullen‐und MOET‐Nukleus‐Programm wurde untersucht und dabei jeweils die Genauigkeit der Schätzung aus Verwandten (Mutter, Voll‐bzw. Halbschwestern) deutlich erhöht.
Models for estimating typical lactation curves in dairy cattle
Authors: Leon‐Velarde C. U. , McMillan I. , Gentry R. D. , Wilton J. W.
Published: March 2011

Milk yields from monthly tests of 59474 Holsteins cows were used to estimate model parameters of the incomplete Gamma, Y(t) = atbe−ct, Compartmental, Y(t) = me−nt (1 ‐ e−p(t‐q)), and Modified Compartmental, Y(t) = ge−ht/(1+e−s(t‐r)), models to describe the shape of typical first lactations, where Y(t) is daily milk production on day t. Gamma parameters were estimated by both linear (L) and non‐linear (NL) procedures. Models were evaluated on the basis of average bias (B) of the estimated 305‐day (305‐d) milk yield compared with that reported under the Agriculture Canada official milk recording program (ROP). Gamma (L) underestimated milk yield more than Gamma (NL) (p < 0.05), and Compartmental more than Modified Compartmental (p < 0.05). When the same cow lactations were used in fitting all three models, the Compartmental model had least bias (p < 0.05). Heritabilities for parameters of the Compartmental model were small (from 0.02 to 0.18). Genetic and phenotypic correlations of parameters from this model with 305‐d milk yield ranged from −0.11 to 0.17. Parameters associated with the beginning of the lactation were positively correlated with 305‐d yield, while the parameter representing decrement of production had a negative correlation.

Modelle zur Schätzung typischer Laktationskurven von Milchrindern

Monatliche Milchtestergebnisse von 59474 Holsteinkühen wurden zur Schätzung von Modellparametern vom kompletten Gamma y(t) = atb e−ct, Compartmentalen, [Y(t) = me−nt (1 ‐ e −p(t‐q),] und modifiziert Compartmentalen, Y(t) = ge −ht/(1+e−s(t‐r)) Modell wurden zur Beschreibung der Formen der typischen Erstlaktationskurven verwendet, wobei y(t) die tägliche Milchproduktion am Tag t symbolisiert. Gamma Parameter wurden zur Schätzung sowohl linearer (L) wie auch nichtlinearer (NL) Methoden geschätzt. Modelle wurden auf der Basis der durchschnittlichen Verzerrung (B) des geschätzten 305 d Milchertrages im Vergleich zu den vom offiziellen Testprogramm berichteten (ROP) bewertet. Gamma (L) unterschätzte den Milchertrag mehr als Gamma (NL) (p < 0,05), und Compartmentales Modell mehr als modifiziert Compartmentales (p < 0,05). Bei Verwendung derselben Kuhlaktationen zur Schätzung der drei Modelle zeigte das Compartmentale Modell die geringste Verzerrung (p < 0,05). Heritabilitätswerte für Parameter des Compartmentalen Modells waren klein (0,02‐0,18). Genetische und phänotypische Korrelationen der Parameter des Modells mit 305 d Milchleistung schwanken von —0,11 bis 0,17. Die mit dem Beginn der Laktation asoziierten Parameter waren positiv mit 305 d Leistung korreliert, während die Parameter zur Beschreibung des Produktionsabfalls eine negative Korrelation zeigten.
Mitochondrial respiratory metabolism and growth performance of lambs. II. Oxygen consumption and oxidative phosphorylation
Authors: Hiendleder S. , Herrmann M. , Waßmuth R.
Published: March 2011

Variation in mitochondrial respiratory metabolism, and associations of mitochondrial characteristics with growth traits, were studied in Merinolandschaf (n = 31) and Rhoenschaf (n = 27) lambs, as well as their reciprocal crosses — Rhoenschaf males × Merinolandschaf females (n = 25) and Merinolandschaf males × Rhoenschaf females (n = 31). Significant genotype effects were detected for all the growth parameters studied. Genotype was also significant for succinate‐mediated state 3 respiration of liver mitochondria (p < 0.01), and approached significance for ATP production with succinate as substrate and glutamate/malate‐mediated state 3 respiration. Significant trial effects (p < 0.001) were observed for all but one of the biochemical parameters studied. Variable patterns of significant correlations between biochemical characteristics and growth traits were detected, which were linked to performance levels of purebred and crossbred lambs. These results indicate that mitochondrial genes could influence growth in lambs via mitochondrial respiratory metabolism.

Respiratorischer Metabolismus von Mitochondrien and Wachstum von Lämmern. II. Sauerstoff‐verbrauch und oxidative Phosphorylierung

An Merinoland (n = 31) und Rhöhnschaflämmern (n = 27) sowie deren reziproken Kreuzungen Rhönscaf ♂ × Merinolandschaf ♀ (n = 25) und Merinolandschaf ♂ × Rhönschaf ♀ (n = 31) wurde die Variation im mitochondrialen Energiestoffwechsel untersucht und Beziehungen zwischen mitochondrialen Parametern und dem Lebendmassezuwachs ermittelt. Signifikante Genotypeffekte wurden bei alien erfaßten Wachstumsmerkmalen beobachtet. Der Effekt Genotyp war ebenfalls bei der succinatinduzierten Atraung von Lebermitochondrien signifikant (p < 0.01) und bewegte sich für die Merkmale ATP‐Produktion und Glutamat/Malat‐induzierte Atmung nahe der Signifikanzgrenze. Mit einer Ausnahme wurden für alle biochemischen Parameter hochsignifikante (p < 0.001) Untersuchungstagseffekte ermittelt. Die Muster signifikanter Korrelationen zwischen biochemischen Werten und Wachstumsmerkmalen waren uneinheitlich und vom Leistungsniveau der genetischen Gruppen abhängig. Die Ergebnisse zeigen, daß mitochondriale Gene Wachstumsmerkmale von Lämmern über den mitochondrialen Energiestoffwechsel beeinflussen könnten.
The inheritance of speed, stamina and other racing performance characters in the Australian Thoroughbred
Authors: Williamson S. A. , Beilharz R. G.
Published: March 2011

It is known that performance in Thoroughbred racing is not a single character. This study analysed horses' performances for a number of parameters which may prove useful to Thoroughbred breeders. Each horse, and subsequently each sire and dam, were given an estimate for their speed, stamina, best distance, and best track condition, and several different measures of peak performance, as well as average performance. Most of these parameters proved highly heritable, with the exception of best track condition. The most startling result was the almost 100% heritability calculated for best racing distance.

If accurate estimates of values for highly heritable parameters such as these were available for all horses in a population, then breeders would be in a much better position to plan matings to obtain a horse which will compete well in a particular type of event. Given the large range of conditions in which Thoroughbreds compete, it would seem more sensible to aim at producing a horse with a specialty ability, rather than hoping to produce one which will excel in all conditions.
Genetic and environmental factors that affect the best time of Thoroughbred horses in Brazil
Authors: Mota M. D. S. , Oliveira H. N. , Silva R. G.
Published: March 2011

On the basis of information provided by the Brazilian Association of Race Horse Breeders, we analysed the racing performance of 947 Thoroughbred horses in races held from 1985 to 1992. The performance was evaluated using the best time of the animals. The variance component was obtained by the derivative‐free restricted maximum likelihood method, and the model used contained fixed effects of the racing month and year, sex, race track, track condition, animal age, number of competitors in race, and distance, and the random animal effect. The low heritability estimate obtained (0.12) indicates that selection based on animal phenotypic value must induce small genetic changes in this trait.

Die Analyse wurde an Rennergebnissen von 947 Vollblutpferden aus den Jahren 1985 bis 1992 durchgeführt, die von der Brasilianischen Rennpferdzüchtervereinigung zur Verfügung gestellt worden waren. Die Leistung wurde an den Bestzeiten der Tiere bewertet. Varianzkomponenten wurden mittels ableitungsfreier Maximum Likelihood Methode geschätzt. Das zugrunde liegende Modell enthielt Rennmonat und‐jahr, Geschbecht, Rennbahn und deren Zustand, Tieralter, Zahl gelaufener Pferde und Distanz als fixe Wirkungen und Tiere als zufällige. Der geringe Heritabilitätswert (0.12) läßt nur geringe genetische Änderungen auf der Basis phänotypischer Selektion erwarten.
Performance of a hyperprolific rabbit line II. Maternal and growth performances
Authors: Cifre J. , Baselga M. , Garcia‐Ximénez F. , Vicente J. S.
Published: March 2011

Maternal and growth traits of a maternal rabbit line (line H), founded selecting on hyperprolificacy, were studied. Line H was compared to line V, a maternal rabbit line with high prolificacy. There were not differences between the two lines for live litter weight at birth when the number of born alive was used as a covariate. Thus, the high prolificacy of line H has not implied any reduction in the viability of the kids at birth or during lactation. Litter weight at 21 days after parturition is superior in line H, which implies a better milk production for its does. The results in that character show how the difference with line V increases with parity order. Additionally individual growth traits were compared between the two lines. Line H showed a higher individual weaning weight than line V, in agreement of its higher maternal abilities also showed with litter weight at 21 days. There were not differences between the two lines for individual weight at the end of the fattening period or individual average daily gain during this period.

Leistung fruchtbarer Kaninchenlinien. II. Maternale und Wachstumsleistungen

Vergleich von Linie H mit einer andern fruchtbaren Linie V zeigt keine Unterschiede im Lebendgeburtsgewicht wenn Wurfgröße als Ko‐Variable verwendet wurde. Hohe Fruchtbarkeit der Linie H führte zu keiner Verschlechterung der Lebensfähigkeit der Jungen. 21‐Tage Wurfgewicht war bei Linie H höher, was auf bessere Milchproduktion hindeutet. Diese Unterschiede nahmen mit Wurffolge zu. Linie H hat auch höheres individuelles Absatzgewicht, aber während der Mastperiode war die Tageszunahme der Mastkaninchen beider Linien nicht unterschiedlich.

Se estudiaron los caracteres maternales y de crecimiento de una nueva línea en conejo de carne (línea H) fundada mediante un esquema de selección por hiperprolificidad. Esta línea se compar con la línea V, una línea de aptitud maternal de elevada prolificidad. No se detectaron diferencias entre las dos líneas para el peso de la camada nacida viva cuando el ndmero de nacidos vivos se utilizó como covariable, lo que supone que la mayor prolificidad de la línea H no ha penalizado la viabilidad de los gazapos al nacimiento o durante la lactación. Además la nueva línea presentó un mayor peso de la camada a 21 días, lo que implica una mayor producción láctea de sus hembras. Los gazapos de la línea H también presentaron un mayor peso individual al destete, lo que sugiere de nuevo las buenas cualidades maternales de la nueva línea. No se observaron diferencias entre los dos tipos de animales para el peso al final del cebo o para la ganancia diaria de peso durante esta fase.
Joint purebred and crossbred (co)variance component estimation with a pseudo multiple trait model: loss in efficiency
Authors: Spilke J. , Groeneveld E. , Mielenz N.
Published: March 2011

Based on simulated data sets, (co)variance component estimation was carried out in a purebredcrossbred situation using a common multiple trait animal model where purebred and crossbred performances were treated as separate traits. The inability of such a model to reflect the special (co)variance structure of purebred‐crossbred data leads to an important bias of the purebred‐crossbred covariance; however, the loss in selection response was small.

Basierend auf simulierten Datensätzen erfolgte bei Nutzung eines Mehrmerkmalsmodells und Modellierung von Reinzucht und Kreuzung als unterschiedliche Merkmale die Schätzung der genetischen Varianzen und Kovarianzen. Das Unvermögen, mit einem solchen Modell die genetischen Varianz‐Kovarianzverhältnisse von Reinzucht‐ und Kreuzungleistungen abzubilden, zeigte sich vor allem in verzerrten Schätzungen der Kovarianzen zwischen den Reinzuchten und der Kreuzung. Der Einfluß dieser Verzerrungen auf den Selektionsverfolg war jedoch gering.