bluuebunny/crossref_metadata_2025 huggingface dataset:
Fractalkine is Not a Major Chemoattractant for the Migration of Neutrophils Across Microvascular Endothelium
Authors: Beck G. Ch. , Ludwig F. , Schulte J. , Van Ackern K. , Van Der Woude F. J. , Yard B. A.
Published: July 2003

Inflammatory responses during sepsis are determined by leucocyte recruitment into inflamed tissues. Both chemokines and adhesion molecules are believed to be involved in this process. As fractalkine exists as transmembrane protein with cell adhesion properties and as soluble chemotactic factor, the present study was conducted to study the role of fractalkine, produced by microvascular and macrovascular endothelial cells, in neutrophil recruitment. Lung microvascular endothelial cells (LMVECs) stimulated with lipopolysaccharide, tumour necrosis factor‐α or interleukin‐1 (IL‐1) produced much more fractalkine compared with the macrovascular human umbilical vein endothelial cells (HUVECs). No differences were found between microvascular endothelial cells of different organs. Chemotactic activity in supernatants was significantly stronger in stimulated LMVEC when compared with HUVEC. Although recombinant fractalkine induced migration of neutrophils, IL‐8 and monocyte chemoattractant protein‐1 were found to be more strictly required. In vivo fractalkine was strongly upregulated in septic lung and kidney. Our data suggest that fractalkine production per se does not explain the preference for inflammation in the lung of septic patients.
Remembrance of Antigens Past: New Insights into Memory T Cells
Authors: Farber D. L.
Published: July 2003

Memory immune responses against foreign antigens protect the host from pathogens previously encountered via illness or vaccination, yet can also contribute to the pathology of autoimmune disease when generated against self‐antigens. Memory immune responses are classically attributed to the reactivation of long‐lived, antigen‐specific T lymphocytes that arise directly from differentiated effector T cells and persist in a uniformly quiescent state. Recent findings in both humans and mice, using new biochemical, molecular and cellular approaches, have identified novel features of memory T cells providing new insight into models for memory cell development and differentiation. Biochemical and molecular studies on memory T cells have identified novel markers for memory T cells that may play integral roles in their generation and maintenance. Recent cellular immunological studies have uncovered remarkable heterogeneity amongst antigen‐specific memory T cells. Memory cell heterogeneity in the expression of homing and chemokine receptor delineates functional subsets of memory T cells that differ in their proliferative capacity, differentiation potential, homing properties and protective abilities. These findings suggest that memory T cells with diverse properties residing in both lymphoid and nonlymphoid tissues may be necessary to elicit a rapid and effective protective recall immune response involving both cellular and humoral immunity.
Agronomic evaluation of precise mechanical hoeing and chemical weed control in sugar beet
Authors: Wiltshire J J J , Tillett N D , Hague T
Published: July 2003

Most herbicide applications to sugar beet (Beta vulgarisL.) are made to the whole crop area, but there is the opportunity to restrict applications to the crop row, decreasing the usage of herbicide by up to 70%. However, this would require greater use of mechanical weed control between rows. Experiments were performed in two seasons to evaluate the weed control performance of a novel, vision‐guided, inter‐row hoe in sugar beet crops grown on a peat fen soil. Hoe lateral placement was within ±30 mm. A precise hoeing and band spraying treatment was compared with overall herbicide use, and with treatments in which the herbicide applications were replaced by hand weeding to minimize competition between crop and weeds. Two hoe passes were made in each season, at crop growth stages of two and 10–12 true leaves in the first season and four and eight true leaves in the second season. Plant population density was not affected by treatment, indicating that none of the treatments caused crop plant loss. Use of the guided hoe controlled weeds better than overall spraying. Crop yields were not significantly different between treatments, indicating that weed control prevented competition with the crop in all treatments.
Effect of air temperature, rain and drought on hot water weed control
Authors: Hansson D , Mattsson J E
Published: July 2003

The influence of rain and drought before, and air temperature during, weed control with hot water was studied in laboratory experiments on the test weedSinapis alba(white mustard). The plants were grown in a greenhouse and treated outdoors. There was no difference in weed control effect whenS. albaplants at the four‐leaf stage were treated at the air temperatures 7°C and 18∘C. The effective energy dose for a 90% fresh weight reduction was 465 kJ m−2for both air temperatures. Weed control ofS. albaat the four‐ to six‐leaf stage in rainfall above the rainwater run‐off level increased the required effective energy dose by 20% (i.e. 120 kJ m−2) compared with dry plants. A short period of drought just before treatment onS. albaat the two‐ to four‐leaf stage increased the plant fresh weight reduction, which was 22% at low energy dose (190 kJ m−2) and 44% at high energy dose (360 kJ m−2). Hot water weed control should thus be carried out when the plants are drought stressed and avoided when the plants are wet. The air temperature seems to be of little importance in the range 7–18∘C.
Towards multifunctional agriculture – weeds as ecological goods?
Authors: Gerowitt B , Bertke E , Hespelt S‐K , Tute C
Published: July 2003

Agricultural land use has production, ecological, aesthetic and social functions. Certainly, in Europe, the concept of agricultural land use as being multifunctional seems to be increasingly accepted. Ecological goods and services can be rewarded as results or as actions – the differences between these ways are described and an outcome‐based rewarding system is elucidated for the creation of incentives for innovation and taking responsibility. The principle requirements for ecological goods are summarized. The contribution of agricultural land use to plant biodiversity is the most appropriated factor for an outcome‐based rewarding system. The various types of vegetation connected with agricultural land use can be used as recognizable ecological goods. The reasoning behind defining specific arable goods is shown. Information about creating the supply is available from the research performed on weed control in different arable systems. As the majority of ecological goods are public goods, mechanisms adapted from market situations for private goods must be stimulated and organized. The decision as to which ecological goods should be stimulated could be transferred to a decentralized and region‐specific public committee in which the relevant stakeholders are represented. Implementation exercises undertaken in a region of the German Federal State of Lower Saxony are introduced.
Retention and degradation of metribuzin in sandy loam and clay soils of Lebanon
Authors: Khoury R , Geahchan A , Coste C M , Cooper J‐F , Bobe A
Published: July 2003

The retention and degradation of metribuzin herbicide were studied under two environmental conditions. Field studies were carried out on two soils, a sandy loam soil (soil A) and a clay soil (soil B). Metribuzin was applied with a jet sprayer at 1060 g a.i. ha−1 and 1960 g a.i. ha−1 on soils A and B respectively. Reconstituted soil columns were used to study the herbicide movement and metabolism in the two soils. Analyses of metribuzin and its metabolites were carried out using standardized methods. The results indicated a very weak capacity of adsorption of metribuzin in the two soils, and the weak adsorbed fraction is easily desorbed. Degradation and mobility of metribuzin in the field and laboratory soil columns were very intense and rapid. Soil A favoured reductive deamination whereas soil B favoured oxidative desulphuration and the respective metabolites deaminometribuzin and diketometribuzin yield the same product deaminodiketometribuzin. Both leaching by rainfall and degradation were important in the disappearance of metribuzin from the soils.
Predispersal seed predation of Amaranthus retroflexus and Chenopodium album growing in soyabean fields
Authors: Nurse R E , Booth B D , Swanton C J
Published: July 2003

Field experiments were made in 1998 and 1999 to determine the influence of tillage and soyabean (Glycine max) row width on predispersal weed seed predation in Amaranthus retroflexus L. (redroot pigweed) and Chenopodium album L. (common lambsquarters). Soyabean was planted in wide (76 cm) and narrow (19 cm) rows with conventional or conservation tillage. Additional control plots without soyabean were also established. The two objectives were to determine (1) whether predispersal seed predation occurs in A. retroflexus or C. album, and (2) whether disturbance (soil tillage) or microclimate (planting pattern) influence predation level. Mean rates of seed predation were 26% and 4% in A. retroflexus and C. album, respectively. Although these levels were low at the population level, individual plants of both species had predation levels ranging from 0% to 80%, however, very few individuals of C. album had levels of predation above 10%. Differences among tillage and row width treatments occurred for A. retroflexus, but not for C. album. Amaranthus retroflexus and C. album growing within the soyabean crop received less light than those in the no‐crop plots, and produced less above‐ground biomass, smaller terminal inflorescences, and fewer seeds per inflorescence. Plant height, terminal inflorescence weight, and total seeds were correlated with predation in both weed species.
Survival, germinability and fungal colonization of dimorphic achenes of the annual weedGalinsoga parvifloraburied in the soil
Authors: Espinosa‐García F J , Vázquez‐Bravo R , Martínez‐Ramos M
Published: July 2003

Galinsoga parviflora(Asteraceae) is a widespread annual weed that produces capitula containing both disc achenes with pappus and ray achenes without pappus. The latter are dispersed within a winged structure formed by capitulum bracts. We buried both achene types in an agricultural soil to be exhumed regularly to investigate whether they differed in survival, germinability and fungal colonization in the soil seedbank. Ray achenes remained viable longer than disc achenes, with different loss rates for the achene types. In both cases, loss rate was very high for the first 10 months, and then loss rates for the achene types tended to level off and even converge by the end of the observation period. The percentage of remaining viable disc achenes was alwaysc.10–15% lower than that of the ray achenes, except on the first and last sampling dates. Germination percentages for viable ray and disc achenes before burial and after exhumation were not statistically different during most of the observation period, except for that between 100 and 200 days of burial (mid‐autumn–winter). There, germination of disc achenes reached 26.4% after 126 days of burial, whereas germination of ray achenes was close to zero. In addition, after 779 days, the germinability of ray achenes was 21.3%, whereas it was 0% for disc achenes. Surface‐disinfected viable disc and ray achenes had low infection rates (0–15%) for both fungi and bacteria during the observation period. The fungal and bacterial infection peaks for both achene types were asynchronous. In general, the expected difference (lower infection rate for ray achenes) was not observed for fungal or bacterial infection.
A decision algorithm for patch spraying
Authors: Christensen S , Heisel T , Walter A M , Graglia E
Published: July 2003

It has been established that weeds are spatially aggregated with a spatially varying composition of weed species within agricultural fields. Site‐specific spraying therefore requires a decision method that includes the spatial variation of the weed composition and density. A computerized decision method that estimates an economic optimal herbicide dose according to site‐specific weed composition and density is presented in this paper. The method was termed a ‘decision algorithm for patch spraying’ (DAPS) and was evaluated in a 5‐year experiment, in Denmark. DAPS consists of a competition model, a herbicide dose–response model and an algorithm that estimates the economically optimal doses. The experiment was designed to compare herbicide treatments with DAPS recommendations and the Danish decision support system PC‐Plant Protection. The results did not show any significant grain yield difference between DAPS and PC‐Plant Protection; however, the recommended herbicide doses were significantly lower when using DAPS than PC‐Plant Protection in all years. The main difference between the two decision models is that DAPS integrates crop–weed competition and estimates the net return as a continuous function of herbicide dose. The hypothesis tested is that the benefit of using lower herbicide doses recommended by DAPS would disappear after a few years because weed density will increase and thus require higher doses. However, the results of weed counting every year did not confirm this hypothesis.
Relationship between speed, soil movement into the cereal row and intra‐row weed control efficacy by weed harrowing
Authors: Cirujeda A , Melander B , Rasmussen K , Rasmussen I A
Published: July 2003

Field trials were carried out at a single Danish and two Spanish locations. In Denmark, winter wheat was sown at 24‐cm row spacing allowing hoeing in the inter‐row area. Hoeing speeds of 2, 5 and 8 km h−1 were tested at the end of tillering, at the beginning of stem elongation or on both occasions. The crop was harrowed immediately after hoeing at the same speed. At the Spanish locations the winter barley was sown at a 12‐cm row spacing and harrowed only, at either pre‐emergence plus post‐emergence, or once post‐emergence at mid‐tillering at 2, 4, 6 and 8 km h−1. The depth of the soil layer thrown into the cereal row was measured at all locations. This layer ranged between 0.4 and 1.4 cm, depending on the site and on the treatment, but was generally higher following a single harrow treatment at all sites. The soil layer only tended to increase with faster speeds at the Danish location. On a more sandy soil and soil rolled prior to treatment, less soil was thrown into the cereal row. When two hoe + harrowing treatments were made, a finer soil structure was achieved. However, this did not affect the weed control. At the Danish location, initial intra‐row weeding efficacy of Brassica napus, based on plant number before and 7 days after treatment, was found to be low (21–41%) but increased to 74–79% when assessed after 45 days. Partial burial and bending of B. napus, together with crop competition, probably suppressed weed growth and enhanced final mortality. Uprooting was probably a more important cause of mortality for Stellaria media. At the Spanish locations, weeding efficacy of Papaver rhoeas was similar, ranging between 58% and 83% and this was achieved soon after harrowing. A thicker soil layer did not result in a greater weed kill. It was therefore suggested that burial alone could not be the main factor responsible for weed control in any of the cases studied. No reduction in wheat biomass, measured at the end of May, was found with increasing speed, or with repeated passes of the harrow. The results suggested that faster harrowing, which is economically more attractive for farmers, could be recommended. The soil layer thrown into the row was not found to be a useful parameter to predict the weed control efficacy in the cases presented.
Genetic uniformity of Alternanthera philoxeroides in South China
Authors: Ye W H , Li J , Cao H L , Ge X J
Published: July 2003

Alternanthera philoxeroides (Mart.) Grisb is an invasive weed that is widespread in a variety of habitats around the world. It was introduced into China in the 1930s, and today occurs in 20 provinces. The level and pattern of genetic diversity of 193 individuals from 11 land‐grown A. philoxeroides populations from South China were determined using 81 intersimple sequence repeat markers. Mean Nei's gene diversity (HE) was 0.0203 ± 0.008, and total diversity (HT) was 0.0286, indicating that genetic diversity in A. philoxeroides in South China is very low. There was a greater proportion of diversity within populations than among (GST =  0.292) populations. Gene flow (Nm) among populations was 0.607. These results are in accordance with the assumption that populations in South China are genetically depauperate because of the short introduction history and the partially clonal propagation of this weed.
Hymenopterous parasitoids of the cherry bark tortrix, Enarmonia formosana (Scopoli) in central‐east Europe (Hymenoptera, Ichneumonoidea; Lepidoptera, Tortricidae)
Authors: Tanigoshi L. K. , Starý P.
Published: July 2003

Strategies targeting the biological control of the cherry bark tortrix (=CBT), Enarmonia formosana (Scopoli) in North America have also included the search for potentially useful native hymenopterous parasitoids of the pest in Europe. The search for such agents undertaken in the central‐east Europe (Czech Republic, Slovak Republic, Hungary) resulted in determination of several ichneumonid species (Campoplex cf. dubitator Horst., Liotryphon sp., Lissonotus sp., Pimpla spuria (Grav.), Pimpla turionellae (L.), and some others, and a braconid (Apanteles britannicus Wilk.) in 2001–2002.
Overview of development of an anti‐attractant based technology for spruce protection againstIps typographus: From past failures to future success
Authors: Jakuš R. , Schlyter F. , Zhang Q.‐H. , Blaženec M. , Vaverčák R. , Grodzki W. , Brutovský D. , Lajzová E. , Turčáni M. , Bengtsson M. , Blum Z. , Gregoiré J.‐C.
Published: July 2003

We describe a series of experiments on the protection of Norway spruce (Picea abies(L.) Karst.) logs and standing trees againstIps typographusL. (Coleoptera: Scolytidae). The tested protective materials were applied 1) at point sources and 2) area‐covering using zeolite‐based dispensers. We performed 11 terrestrial and one aerial application (using a helicopter) between 1992 and 2001. We gradually replaced polyethylene‐bag verbenone dispensers by composite dispensers releasing verbenone and non‐host volatiles (NHV: green leaf volatiles,trans‐conophthorin, and C8‐alcohols). Many experiments did not give statistically significant results, due to the low number of true replicates and the spatial heterogeneity of beetle attacks. The protection of horizontal objects like logs or lying trees with anti‐attractants was not always successful. In the future, positive results can be expected with an area covering spray applied by zeolite dispensers containing mixtures of verbenone and NHV. A similar approach could probably be used in aerial spraying of anti‐attractants.

We have succeeded in our attempt to protect zones of standing spruce trees fromI. typographusattacks. We used dispensers with a combination of verbenone and a full blend of NHV compounds. The protection is not complete, but in both 2000 and 2001, the treatment significantly decreased the probability of the insect attack on trees by 60–80 %.
Analysis of two Chinese yak (Bos grunniens) populations using bovine microsatellite primers
Authors: Minqiang Wang , Weigend S. , Barre‐Dirie A. , Carnwath J. W. , Zhonglin L. , Niemann H.
Published: July 2003

Two Chinese domestic yak populations representing the Plateau type and the Huanhu Alpine type were analysed with 12 bovine microsatellite primers. All primer pairs functioned in the yak genome and polymorphism was found at all loci. The allele size ranges and frequencies of the two yak populations were similar and there was considerable overlap with the allele size ranges observed in cattle. Data for European cattle breeds was obtained from the Cattle Diversity Database (CaDBase) to interpret the heterozygosity and genetic distance estimates in yak populations. Heterozygosity estimated for the two yak populations was comparable with that of European cattle while Nei's Genetic Distance DA between the two yak populations was less than distances between the most closely related German cattle breeds. Bovine microsatellite primers proved to be a valuable tool for characterization of yak populations.
Early growth performance of Bos taurus × Bos indicus cattle crosses in Ethiopia: estimation of individual crossbreeding effects
Authors: Demeke S. , Neser F. W. C. , Schoeman S. J.
Published: July 2003

In an effort to estimate breed differences, heterotic and recombination effects, a total of 4957 birth weight (BWT), 4245 weaning weight (WWT) and 3330 yearling weight (YWT) records collected from 38 crossbred and three purebred genotypes generated from crossing Friesian (F), Jersey (J) and Simmental (S) with the Boran (Bo), Barca (Ba) and Horro (Ho) (Bos indicus) breeds in Ethiopia were used. Differences between genotypes were significant (p < 0.01) for all traits. Genetic group mean values adjusted for environmental effects ranged from 20 to 30 kg for BWT, 88 to 114 kg for WWT, 122 to 157 kg for YWT and 358 to 492 g for preweaning average daily gain (ADG). The breed additive effect of F as a deviation from the Bo was significant (p < 0.01) and positive for all traits. Relative to the Bo mean, the additional breed additive contributions of the F breed on BWT, WWT, ADG and YWT were 39.3, 16.5, 9.3 and 10.3%, respectively. However, the breed additive effects of the Ho and J breeds were significantly (p < 0.01) negative for all traits. The heterotic effects were significantly negative (p < 0.01) for BWT for all F and S crosses, but positive (p < 0.01) on all other traits for all types of crosses. The average heterosis estimated within the F, J and S breeds were: −2.1 ± 0.6, 0.2 ± 0.6 (p > 0.05) and −2.3 ± 0.6 kg for BWT, 8.82.1, 11.8 ± 2.3 and 13.7 ± 2.4 kg for WWT, 60.4 ± 11.3, 64.8 ± 12.3 and 90.6 ± 12.7 g for ADG, and 19.8 ± 2.6, 19.5 ± 2.8 and 20.8 ± 2.9 kg for YWT, respectively. The recombination effects were significant (p < 0.01) for the majority of crosses for all traits. The estimates of the recombination loss were negative in all traits, except for BWT. The average recombination effects estimated within the F, J and S breeds were: 2.6 ± 0.8, 2.9 ± 0.9 and 2.4 ± 1.0 kg for BWT, −13.6 ± 3.2, −4.2 ± 3.4 (p > 0.05) and −16.0 ± 4.0 kg for WWT, −88.0 ± 17.1, −39.4 ± 18.4 and −102.2 ± 21.3 g for ADG, and −14.4 ± 4.0, −0.1 ± 4.4 (p > 0.05) and −17.5 ± 4.9 kg for YWT, respectively. It could be concluded that the breed differences, heterotic and recombination effects seem to be important genetic factors affecting early growth performances in the breed crosses tested.
Genetic parameters of somatic cell count in dairy sheep considering the type of mammary pathogen effect
Authors: Gonzalo C. , Ariznabarreta A. , Othmane M. H. , Carriedo J. A. , De La Fuente L. F. , San Primitivo F.
Published: July 2003

Genetic parameters for somatic cell count (SCC) from half‐udder milk were estimated from 4692 monthly test‐day records from each half‐udder of 1337 Churra ewes belonging to seven dairy flocks. The total number of observations was 9348. Variance and co‐variance genetic components were estimated using a multitrait repeatability animal model. The log SCC of the right and left half‐udders were considered as two dependant variables in the model. The species of organisms causing intramammary infection were identified and included or not in the analysis as a fixed effect. The inclusion of the mammary pathogen fixed effect did not influence the estimation of heritability. However, the proportions of permanent environmental variance and repeatability were significantly reduced in comparison with the model that did not include this effect. On the other hand, the genetic correlation between SCC in milk from left and right glands was close to unity, and no differences were detected between both glands for all genetic estimates. The importance of the mammary pathogen factor was evaluated in comparison with the other fixed effects studied, which in relation were of little importance.
Bayesian analysis of heritability of canine hip dysplasia in German Shepherd Dogs
Authors: Hamann H. , Kirchhoff T. , Distl O.
Published: July 2003

Variance components and heritability were linearly estimated for canine hip dysplasia (CHD) in German Shepherd Dogs using a Bayesian analysis based on the marginal posterior distributions of parameters achieved via Gibbs sampling. Data was provided by the German Shepherd Breeding Association in Augsburg. The material included 21 371 X‐rayed dogs born in the years 1998–2000 in 3755 kennels from 9704 litters. The pedigree file consisted of 38 604 animals and contained ancestors for up to six generations. The full model used considered the fixed effects of sex, age at examination for CHD, the examining veterinary expert, the combined effect of litter size and percentage of examined dogs per litter, and the sire and mother lines as well as the additive genetic random effects of the animal and of the mother, the permanent environmental effect of the litter and the kennel. Submodels were compared with the full model to evaluate the importance of different fixed and random effects, and their influence on other model components. Heritability estimates in the full model wereh2 = 0.26 ± 0.03 (additive genetic animal effect) and = 0.10 ± 0.02 (additive genetic maternal effect). The direct animal and the maternal effects were negatively correlated genetically (ram = −0.65 ± 0.05). The proportion of the variance of the random effect of the common kennel of the total variance was always below 0.015, whereas the corresponding proportion of variance of the random effect of the common litter effect reached a value of 0.045. When submodels were employed, the heritability estimates for the additive genetic animal effect ranged fromh2 = 0.24 toh2 = 0.26. The heritability estimates for the additive genetic maternal effect varied between = 0.09 and = 0.10.
Genetic change of feed intake curves in growing pigs using non‐linear two‐stage genetic analysis and linear random regression models
Authors: Lorenzo Bermejo J. , Roehe R. , Schulze V. , Looft H. , Kalm E.
Published: July 2003

Longitudinal data of daily feed intake from 5245 young boars were analysed in this study in order to improve feed efficiency by changing the feed intake curve. Individual logistic and linear‐segmented functions were fitted, based on daily data of feed intake per boar, recorded during a test period of 9 weeks. Heterogeneous variance was considered by means of the power‐of‐the‐mean variance model. The mean estimated day on test corresponding to maximum increment in feed intake varied from 71 to 81 days using logistic function, and the mean estimated day on test at which the feed intake plateau was reached varied from 45 to 48 days on test, using a linear‐segmented function. High differences in the individual variation pattern of feed intake were obtained. A mixed model was fitted to individual estimates of function parameters. The uncertainty in individual estimation was taken into account by incorporating the estimated asymptotic covariance matrices. Estimates of heritability for parameters characterizing feed intake at the beginning of the test period ranged from 0.03 to 0.30. Selection based on parameters of a logistic function, using absolute residual estimation of variance heterogeneity, reduced feed intake at the end of the test period by 0.2 kg/day, while feed intake at the beginning of the test was slightly modified. With increasing individual information on daily feed intake, the two‐stage method was recommended. If individual observations on daily feed intake are sparse, random regression models were preferred in order to change the feed intake curve for breeding purposes.
Phenotypic correlations as substitutes to genetic correlations in dairy sheep and goats*
Authors: Kominakis A. P.
Published: July 2003

A data set of n = 67 pairs of genetic and phenotypic correlation estimates for various milk traits, constructed from an exhaustive survey of published estimates in dairy sheep and goats, was used to test whether the phenotypic correlation (rP) may be a suitable replacement of the genetic correlation (rG). Various criteria to assess the closeness of the two estimates were used: Pearson‐, Spearman‐ and bootstrapped‐ correlations, paired sample t‐test and non‐parametric tests. Correlations between paired genetic and phenotypic correlation estimates were generally found to be high (from 0.87 to 0.95) and not statistically different between the two species. Employment of a paired sample t‐test showed that the average difference between the genetic and phenotypic correlation estimates (d = rG − rP) was significantly (p < 0.05) different from zero only for dairy goats (d = 0.11). Comparisons of correlation estimates either after employment of Fisher's transformation or of a non‐parametric test (Kruskall–Wallis) showed that there was statistically no significant difference (p < 0.05) between the two estimates. The main sources of variation for pooled (sheep and goat) d were the year of publication, the method of estimation and the heritabilities of the traits. Furthermore, differences between the two estimates were caused by sampling errors of the genetic correlations. Although average reported standard errors of genetic correlations were found to be about 30% higher than the theoretically expected correlations, the difference between the two errors was not statistically significant (p < 0.05). A simulation study of two correlated traits displaying heritabilities, genetic, environmental and phenotypic correlations equal to the average literature estimates was also performed to investigate the effects of using rP instead of rG on the direct and indirect true selection responses and on the accuracy of the breeding values. Based on the results of the descriptive and simulation analysis for the species, traits and correlation structure examined here, phenotypic correlations may be substituted for genetic correlations when the latter are unavailable or are not precisely estimated.
Serum insulin‐like growth factor‐1 concentration in pigs divergently selected for daily food intake or lean growth rate
Authors: Cameron N. D. , McCullough E. , Troup K. , Penman J. C.
Published: July 2003

Divergent selection over seven generations for daily food intake (DFI) and for two lean growth rate (LGA and LGS) selection objectives in pigs produced correlated responses in serum insulin‐like growth factor‐1 (IGF‐1) concentration. The LGA and LGS selection objectives were for lean growth, but with performance testing on ad libitum (LGA) or on restricted (LGS) feeding regimes. There were 342 animals in the study, with an average of 46 pigs in each selection line and 72 pigs in the control line. All animals were performance‐tested from 30 to 90 kg on an ad libitum feeding regime. Selection on DFI increased IGF‐1 at 6 weeks of age (158 versus 104 μg/l, SED 21; control 136 μg/l) and selection for high LGA increased IGF‐1 at 30 kg liveweight (202 versus 161 μg/l, SED 14; control 185 μg/l). At 6 weeks of age and at 30 kg of weight, there was no response in IGF‐1 with selection on LGS (128 versus 129 and 167 versus 153 μg/l, respectively) suggesting that IGF‐1 may not be a reliable physiological predictor of genetic merit for such a selection objective, which combined rate and efficiency of lean growth. IGF‐1 measured immediately prior to the start of performance test may be useful in determining which animals to performance test for a lean growth selection objective, whereas IGF‐1 measured at 6 weeks of age may be a useful physiological predictor of genetic merit for daily food intake during performance test.
Experimental Field Trial with an Immunostimulating Complex (ISCOM) Vaccine against Contagious Bovine Pleuropneumonia
Authors: Hübschle O. J. B. , Tjipura‐Zaire G. , Abusugra I. , Di Francesca G. , Mettler F. , Pini A. , Morein B.
Published: July 2003

The experimental field trial with an immunostimulating complex (ISCOM) vaccine has been an occasion to explore the role of a Th1 response in the pathogenesis caused by Mycoplasma mycoides subsp. mycoides small colony (MmmSC) and in immune protection. The ISCOM complex is known to promote Th1 response. Antibodies to MmmSC were detected by indirect enzyme‐linked immunosorbent assay (ELISA) in the vaccinated cattle, although the levels were lower than in a previous study. No antibodies were detected by complement fixation test (CF). After the challenge infection, vaccinated animals developed CF antibody response. They showed significantly reduced mortality compared with controls. However, gross pathological and histopathological score for vaccinated animals was as high as for the non‐vaccinated, characterized by a high inflammatory reaction with histopathology dominated by interlobular pneumonia with vasculitis.
Atypical Myxomatosis – Virus Isolation, Experimental Infection of Rabbits and Restriction Endonuclease Analysis of the Isolate
Authors: Pšikal I. , Šmíd B. , Rodák L. , Valíček L. , Bendová J.
Published: July 2003

Atypical form of myxomatosis, which caused non‐lethal and clinically mild disease in domestic rabbits 1 month after immunization with a commercially available vaccine MXT, is described. The isolated myxoma virus designated as Litovel 2 (Li‐2) did not induce systemic disease following subcutaneous and intradermal applications in susceptible experimental rabbits but led to the immune response demonstrated by ELISA. No severe disease was induced in those Li‐2 inoculated rabbits by challenge with the virulent strains Lausanne (Lu) or Sanar (SA), while the control animals showed nodular form of myxomatosis with lethal course of the illness. Restriction fragment length polymorphism (RFLP) of genomic DNA with KpnI and BamHI endonucleases was used for genetic characterization of the Li‐2 isolate, the vaccine strain MXT and both virulent strains Lu and SA, respectively. In general, RFLP analysis has shown to be informative for inferring genetic relatedness between myxoma viruses. Based on restriction endonuclease DNA fragment size distribution, it was evident that the pathogenic strain SA is genetically related to the reference strain Lu and the isolate Li‐2 is more related, but not identical, to the vaccination strain MXT.
Detection of Antibodies to Alphaviruses and Discrimination between Antibodies to Eastern and Western Equine Encephalitis Viruses in Rabbit Sera using a Recombinant Antigen and Virus‐specific Monoclonal Antibodies
Authors: Pässler S. , Pfeffer M.
Published: July 2003

Three arthropod‐borne alphaviruses, western equine encephalitis viruses (WEEV), eastern equine encephalitis viruses (EEEV) and Venezuelan equine encephalitis viruses are the aetiological agents of a sometimes severe encephalomyelitis in equines and humans in the New World. With regard to the different ecology and epidemiology of these viruses, a method applied in serological screening should be able to distinguish between them as well as other related members of the genus Alphavirus in the American continent. However, this has been hampered in the past by (a) the close antigenic relationship between alphaviruses in traditional serological assays, especially in the routinely used haemagglutination‐inhibition, and (b) the need of biosafety level 3 facilities to grow the viral antigens. An epitope blocking assay using an EEEV glycoprotein E1‐expressing recombinant Sindbis virus and virus‐specific monoclonal antibodies (mAbs) binding to the E1 of EEEV (strain NJ/60) and the E1 of Sindbis virus was established using automated flow cytometry. The test was evaluated using sera of infected and vaccinated rabbits. A cut‐off value of 30% inhibition for antigenic complex‐specific seroconversion was found to be sufficient for the detection of the respective infection. By using three different mAbs in parallel, we were able to detect alphavirus genus‐, EEEV‐ and WEEV‐complex‐specific serum antibodies. As this test is based on the inhibition of binding of virus‐specific mAbs, sera of every origin other than mouse can be tested. Thus, this assay may prove useful in the serological screening of a variety of animal species during an outbreak investigation.
Reproductive Losses due toNeospora caninumin a Beef Herd in Argentina
Authors: Moore D. P. , Campero C. M. , Odeón A. C. , Chayer R. , Bianco M. A.
Published: July 2003

Reproductive losses in a beef herd of 857 heifers with a pregnancy rate of 86.3% are described. After pregnancy testing, 69 abortions were seen during a 3 month period. Before calving season, three heifers had delivered pre‐mature non‐viable calves. Serum samples from 58 of 69 aborted heifers were available for serological tests. In order to compare the seroprevalence in non‐aborted vs. aborted heifers, 214 pregnant animals were bleed during the abortion storm. In addition, blood samples were collected from two heifers with pre‐mature calves and from 16 heifers with their calves prior to colostrum intake. All available serum samples were tested forNeospora caninumantibodies using an indirect fluorescence antibody test (IFAT). Fifty‐nine of 290 (20.3%) evaluated heifers were seropositive. Heifers that aborted and heifers with pre‐mature calves were more likely to be seropositive than pregnant heifers and heifers with normal calves [odds ratio (OR), 12.01; 95% CI, 6.18–23.30]. Vaginal mucus from four aborted heifers, and samples from two aborted foetuses and three pre‐mature calves were available. Laboratory tests forTritrichomonas foetus, bacterial and viral isolation, and histological examination were performed. Culture from vaginal mucus and foetal samples were negative. Histological lesions consistent with neosporosis and positive immunohistochemistry (IHC) toN. caninumwere found in one aborted foetus and in one pre‐mature calf. It is the first description of reproductive losses because ofN. caninumin beef herds in Argentina.
Effect of Endobronchial Challenge withActinobacillus pleuropneumoniaeSerotype 10 of Pigs Vaccinated with Bacterins Consisting ofA. pleuropneumoniaeSerotype 10 Grown under NAD‐Rich and NAD‐Restricted Conditions
Authors: van Overbeke I. , Chiers K. , Donne E. , Ducatelle R. , Haesebrouck F.
Published: July 2003

The efficacy of two bacterins containing anActinobacillus pleuropneumoniaeserotype 10 strain was evaluated. The bacterial cells constituting bacterin 1 and 2 were grown under nicotinamide adenine dinucleotide (NAD)‐rich (low‐adherence capacity to alveolar epithelial cell cultures) and NAD‐restricted (high‐adherence capacity to alveolar epithelial cell cultures) conditions, respectively. Ten pigs were vaccinated twice with the bacterin 1 and nine pigs with the bacterin 2. Ten control animals were injected twice with a saline solution. Three weeks after the second vaccination, all pigs were endobronchially inoculated with 106.5 colony‐forming units (CFU) of anA. pleuropneumoniaeserotype 10 strain. In the bacterin 1 and 2 group, three and two pigs died after inoculation, respectively. Only two pigs of the control group survived challenge. Surviving pigs were killed at 7 days after challenge. The percentage of pigs with severe lung lesions (>10% of the lung affected) was 100% in the control group, 70% in the bacterin 1 group and 22% in the bacterin 2 group.Actinobacillus pleuropneumoniaewas isolated from the lungs of all animals. The mean bacterial titres of the caudal lung lobes were 7.0 × 106 CFU/g in the control group, 6.3 × 105 CFU/g in the bacterin 1 group and 1.3 × 106 CFU/g in the bacterin 2 group. It was concluded that both bacterins induced partial protection against severe challenge. Furthermore, there are indications that the bacterin 2, containingA. pleuropneumoniaebacteria grown under conditions resulting in highin vitroadhesin, induced better protection than the bacterin 1.
A Study about Tick Vectors of Bovine Theileriosis in an Endemic Region of Iran
Authors: Razmi G. R. , Ebrahimzadeh E. , Aslani M. R.
Published: July 2003

The aim of this study was to determine the population of ticks in infected cattle and to identify the tick vectors of bovine theileriosis in an endemic area of Iran from 1998 to 1999. A total of 120 suspected cattle suffering from theileriosis were clinically examined and investigated for the presence of Theileria annulata in blood smears and the presence of any tick species on the body of cattle. In this study, 680 ticks were collected from 107 cattle infected with T. annulata. The prevalence of ticks infesting cattle was 92.35%Hyalomma anatolicum excavatum, 5.14%H. marginatum marginatum, 1.17%H. asiaticum asiaticum and 1.32%Rhipicephalus sanguineus. The examination of 510 tick salivary glands revealed that 51% of H. a. excavatum and 1.3% of H. a. asiaticum were infected with sporozoites of T. annulata.
Isolation of Campylobacter jejuni and Campylobacter coli from the Gall Bladder Samples of Sheep and Identification by Polymerase Chain Reaction
Authors: Ertaş H. B. , Özbey G. , Kılıç A. , Muz A.
Published: July 2003

In this study, 100 gall bladder samples of sheep slaughtered at an abattoir in Elazıgˇ province were examined for Campylobacter jejuni and Campylobacter coli by culture and polymerase chain reaction (PCR). Preston Campylobacter Agar supplemented with 7% horse blood and Preston Selective Supplement (Oxoid, Hampshire, UK) were used for isolation of the agents. Campylobacter spp. were isolated in 66 samples, and they were identified as 34%C. jejuni and 32%C. coli.

A multiplex PCR based upon the use of ceuE gene‐specific primers was applied on DNA samples extracted from C. jejuni and C. coli isolates. All C. jejuni and C. coli strains that were positive by culture were also detected to be positive by PCR.

This study shows that PCR can be used an alternative, rapid and sensitive test for the identification of C. jejuni and C. coli which threaten human and animal health.
Experimental Infections with Wild and Mutant Yersinia pseudotuberculosis Strains in Rabbits
Authors: Najdenski H. , Vesselinova A. , Golkocheva E. , Garbom S. , Wolf‐Watz H.
Published: July 2003

Experimental oral infections of rabbits with a wild‐type Yersinia pseudotuberculosis strain (pIB102), and two null‐mutants (yopK and ypkA) were carried out with the aim to explore the possibility to use mutant strains of Y. pseudotuberculosis as live carrier vaccine strains.

The infectious process of the three strains proceed with passing hyperthermia, leucocytosis with granulocytosis, moderate monocytosis and a transient lymphopenia, better demonstrated at mutant strain infections. Short‐term bacterial dissemination into the brain and viscera was observed at yopK infection. An augmented resistance to bactericidal activity of leucocytes at the initial phase of infection was followed by an increased sensitivity discovered earlier in case of yopK strain accompanied by at least 70‐ and 20‐fold, respectively, for ypkA lower virulence for mice. The level of attenuation of yopK was accompanied by significant Yersinia specific IgG and IgM antibody response. Inflammatory foci were found by morphological examination in brain, lung and small intestines after infection with the wild‐type strain, while such foci were only observed in brain and mesenterial lymph nodes after infection with the yopK mutant. After infection with the ypkA mutant foci were found in brain and spleen of the infected animals. Morphological changes in the lymphatic tissue of rabbits infected with mutant strains were consistent with induction of immunogenesis.

The data suggest that genetically constructed yopK null‐mutant exhibits characteristics that makes the strain suitable to be used as a live carrier vaccine to deliver heterologous antigens.
Novel Employment of Lactate Dehydrogenase Release from Porcine Aortic Endothelial Cells (PAEC) as a Quantitative Marker of Cytotoxic Activity in Thermophilic Campylobacter spp. from Human Faecal Isolates, Poultry and Environmental Sources
Authors: Millar B. C. , McCarron M. , Murphy P. G. , Moore J. E.
Published: July 2003

The aim of this study was to employ a novel cytotoxicity assay based on primary porcine aortic endothelial cells in combination with a lactate dehydrogenase release assay to quantitatively determine differences in cytotoxin production between Campylobacter jejuni, C. coli, C. lari and urease‐positive thermophilic campylobacters (UPTC), isolated from human faeces, animals and environmental sources. Campylobacter isolates totalling 34 and comprising of C. jejuni (n = 24) C. coli (n = 5) and UPTC (n = 4) and C. lari (n = 1) were analysed. The cytotoxic response ranged from 32.15 to 64.47% and 33.08 to 59.41%, for C. jejuni from chicken and human isolates, respectively and there was no statistically significant difference (P > 0.05) in cytotoxic response between C. jejuni isolated from humans and chicken isolates (50.78% versus 50.55% cytotoxicity, respectively). However, there was a difference in response between C. jejuni and C. coli isolated from chickens (50.78% versus 33.22% cytotoxicity, respectively). The greatest cytotoxic response was obtained with the UPTC group of organisms examined (n = 4 isolates) (mean cytotoxic response = 57.11% cytotoxicity. Employment of this cytotoxin assay may help identify virulent strains in poultry that could potentially proceed to cause clinical problems for humans and thus intervention measures targeted at the reduction or elimination of such specific strains, may be sought.
Equine Viral Arteritis in a Newborn Foal: Parallel Detection of the Virus by Immunohistochemistry, Polymerase Chain Reaction and Virus Isolation
Authors: Szeredi L. , Hornyák Á. , Dénes B. , Rusvai M.
Published: July 2003

A 4‐days‐old foal died after a short course of respiratory syndrome and fever. Large areas of the alveoli, bronchioles and bronchi were partly or completely filled by hyaline membranes. Pronounced oedema and mild interstitial pneumonia were present and, in the small muscular arteries, fibrinoid necrosis and vasculitis or perivasculitis could be seen. Vasculitis was found in several other organs, and it was most severe in the thymus. The virus was detected in the lung, kidney and spleen using virus isolation and in the lung and spleen using polymerase chain reaction. The virus was also detected in several organs and cell types using both N protein‐specific monoclonal antibody and horseradish peroxidase‐labelled equine arteritis virus‐specific equine IgG.
Life Cycle and Population Dynamics of the Polychaete Perinereis cultrifera from the Algerian Mediterranean Coast
Authors: Rouabah Abdelkader , Scaps Patrick
Published: July 2003

Abstract. The polychaete Perinereis cultrifera (Grube, 1840) (Nereididae) is common along Algerian coasts in algal‐covered hard bottoms. An intensive study was conducted from June 2000 to June 2001 to characterise the life cycle of an intertidal and upper subtidal population of P. cultrifera in Algeria near the Tunisian border (30 km). P. cultrifera has a 3‐year life span and reproduces exclusively by epitoky. The reproductive season is short, and spawning occurs in late April/early May when the sea‐water surface temperature starts rising. Female sexual differentiation starts in February in the second year of life; thus, the oocytes take 16 months to mature and their diameter at maturity is approximately 250 μm.