bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of commercial chicory cultivars for hydroponic forcing and their phenetic relationships revealed by random amplified polymorphic DNAs and amplified fragment length polymorphisms
Authors: Stallen N. Van , Noten V. , Demeulemeester M. , Proft M. De
Published: March 2003

One‐hundred and twenty‐four amplified fragment length polymorphism (AFLP) and 49 random amplified polymorphic DNA (RAPD) markers have been used to distinguish between 20 and 23 commercial chicory cultivars, respectively. These were all Cichorium intybus var. foliosum F1 hybrids, currently used in hydroponic forcing. Five‐hundred and twenty RAPD primers (OPERON) were tested, of which 156 resulted in reproducible patterns and 26 yielded polymorphisms. Two‐hundred and fifty‐six AFLP primer‐combinations were tested and six combinations were selected for identification purposes. Similarity indices were measured and clustering has been done using pairwise comparison. Both types of marker provide similar conclusions. Two major clusters are formed, representing late and early cultivars. All cultivars were identified using 10 informative RAPD primers or three AFLP primer combinations. A low degree of polymorphism was detected between some early cultivars, suggesting a narrow genetic base in their breeding strategy.
Chloroplast microsatellite variations in tetraploid alfalfa
Authors: Mengoni A. , Ruggini C. , Vendramin G. G. , Bazzicalupo M.
Published: March 2003

Four chloroplast simple sequence repeat (cpSSR) loci were identified in alfalfa (lucerne), Medicago sativa L. The occurrence of allelic variation at these loci was evaluated in 100 plants from 10 populations of tetra‐ploid alfalfa, belonging to four Italian ecotypes and to an Italian (‘Lodi’) and an Egyptian (‘Iside’) variety. Twenty‐four different alleles were identified, four of which were exclusive to the ‘Iside’ variety. The genetic relationship among plants and among populations was analysed by computing an analysis of molecular variance and an unweighted pair group means analysis clustering. This analysis allowed clear separation of the ‘Iside’ variety from Italian germplasm and the recognition of close relationships within the Italian populations. The data presented suggest that cpSSR analysis of tetraploid alfalfa could be used for germplasm polymorphism analysis.
Analysis of D‐prolamins synthesized by the Hordeum chilense genome and their effects on gluten strength in hexaploid tritordeum
Authors: CABALLERO L. , ALVAREZ J. B. , MARTIN L. M.
Published: March 2003

Hexaploid tritordeum is the amphiploid derived from the cross between Hordeum chilense and durum wheat. The storage proteins synthesized in the Hch genome influence the gluten strength of this amphiploid. The D‐prolamins of H. chilense have been analysed by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis with and without urea. A new locus named Glu‐Hch3 has been detected. The effects of allelic variation at this locus on gluten strength, as measured the sodium dodecyl sulphate sedimentation test, were determined using seeds of 92 lines from a cross of two hexaploid tritordeum lines. Two allelic variants have been detected for this locus, which have shown different effects on gluten strength.
Genetic analysis of the nitrogen and phosphorus utilization efficiencies in mature spring barley plants
Authors: Górny A. G. , Sodkiewicz T.
Published: March 2003

Inheritance of the efficiency of nitrogen and phosphorus utilization in grain production was studied in diallel hybrids of spring barley. Effects of varied NPK fertilization and soil moisture on the genetic variance was evaluated at maturity in pot‐ and field‐grown plants. A preponderance of general combining ability effects was found for the efficiency ratios and utilization efficiencies, suggesting that the generative efficiency indices were mainly controlled by an additive genetic system. However, the relatively high narrow‐sense heritabilities (0.33‐0.81) found under optimal conditions tended to decline to 0.00‐0.36 following water and nutrient shortages. The importance of non‐additive gene effects for utilization efficiencies was demonstrated in the field under reduced nutrition. This leads to the conclusion that the involvement of additive gene action should facilitate selection efforts only under favourable environments. Selection delayed until later hybrid generations should be used when trying to improve the nutrient efficiency of barley under less favourable nutrition conditions.
Inheritance of the sesquiterpenes longipinenone and hydroxy‐longipinenone within the Achillea millefolium complex (Compositae)
Authors: Fischer U. , Vetter S. , Novak J. , Glasl S. , Saukel J. , Franz C.
Published: March 2003

Three selfing and 13 crossing experiments between tetraploid individuals of Achillea ceretanica, Achillea collina, Achillea distans ssp.‘styriaca’ Saukel (ined.), and Achillea pratensis (Achillea millefolium complex, Compositae), five F1 crosses, three backcrosses and one further selfing experiment were carried out in order to study the inheritance of longipinenone (1) and its hydroxyl derivative (2). From these crossings, 1294 plants were studied by qualitative thin layer chromatography. Progenies from parent and F1 plants without longipinenones (0‐type, ll) uniformly contained none of these two sesquiterpenes. All other crossing experiments showed typical segregation patterns of 0‐type, L‐type (longipinenone (1) without hydroxylongipinenone, L.hh) and H‐type (hydroxy‐longipinenone (2) and occasionally longipinenone, L.H.) in the ratio of 1 : 1 and 1 : 3. According to these results both derivatives are under dominant genetic control regulated by genes L and H, whereby hydroxylation takes place after synthesis of longipinenone (1).
Genetic mapping of a major gene delaying blooming time in almond
Authors: Ballester J. , Socias i Company R. , Arus P. , De Vicente M. C.
Published: March 2003

The objective of this study was to determine the genetic basis of late blooming in almond. Molecular markers were used to study the Late bloom gene (Lb), responsible for a delay of blooming time, in an F1 segregating population of 134 plants. Using a qualitative approach, the Lb gene was located on linkage group 4 of the almond map, flanked by markers AG6 and FG3. The quantitative analysis confirmed the presence of a major gene on linkage group 4, which explained at least 79% of the phenotypic variation. On average, the plants with the Lb allele bloomed 15 days later and the Lb allele showed dominant gene action. In addition, three RAPD markers associated with the Lb gene were identified by bulked segregant analysis. One was placed at 5.4 cM from Lb and could be used as a diagnostic marker for flowering time.
The accumulation pattern in developing seeds and its relation to fatty acid variation in soybean
Authors: Ishikawa G. , Hasegawa H. , Takagi Y. , Tanisaka T.
Published: March 2003

Sixty soybean cultivars from Japan and the USA formed five maturity groups (IIb‐Vc) based on number of days from sowing to flowering and number of days from flowering to maturity. Highly significant intervarietal differences in fatty acid composition were found in all the maturity groups, especially in IIc. Stearic and oleic acids showed a larger variation than palmitic, linoleic and linolenic acids. Principal component analysis suggested that the total variation of fatty acid composition depended mainly on the desaturation levels from oleic to linoleic acid. Three cultivars exhibiting unique fatty acid composition, together with a standard cultivar, were examined for the contents of the five fatty acids, as well as crude oil at eight seed‐filling stages. For all four cultivars, it was found that crude oil content increased sigmoidally with advancing filling stage, and that the accumulation patterns of palmitic, linoleic and linolenic acids were similar to that of crude oil. However, the accumulation pattern of stearic acid was different from that of crude oil and divided the cultivars into two distinct groups. For oleic acid, only the cultivar ‘Aburamame’ showed a rapid increase in proportion with advancing filling stage, although not differing markedly in accumulated content from the other cultivars. These results indicate that analysing the accumulation patterns of fatty acids could explain the latent genetic variation in fatty acid composition of soybean seeds.
Use of chlorophyll fluorescence to evaluate the cold acclimation and freezing tolerance of winter and spring oats
Authors: Rizza F. , Pagani D. , Stanca A. M. , Cattivelli L.
Published: March 2003

The efficiency of the excitation capture by open Photosystem II (PSII) reaction centres was measured by the Fv/Fm ratios in a collection of winter and spring oats in order to assess the effects of hardening and freezing on the functionality of PSII and also the suitability of a chlorophyll fluorescence‐based method to screen oat cultivars for frost tolerance. A significant reversible decrease in Fv/Fm was found in all genotypes during acclimation to low, non‐freezing temperatures. Fv/Fm analysis appears to be an attractive test for the evaluation of frost tolerance in oats, being rapid, non‐invasive and capable of monitoring a trait related to a crucial stage in the acquisition of frost tolerance. It is more sensitive and precise than other standard methods and highly correlated with field‐evaluated frost damage. The measurements made during recovery 1 or 2 days after stress when the visual symptoms are not yet expressed, were especially advantageous because of the large variability in genotype response. The r‐values (close to 0.8) were reduced due to the non‐standard behaviour of the winter cultivar ‘Aintree’. The cold acclimation response of this genotype has been analysed in detail and the limits of artificial freezing tests are discussed.
Production of yellow‐seeded Brassica napus through interspecific crosses
Authors: Rahman M. H.
Published: March 2003

Yellow‐seeded Brassica napus was developed from interspecific crosses between yellow‐seeded Brassica rapa var.‘yellow sarson’ (AA), black‐seeded Brassica alboglabra (CC), yellow‐seeded Brassica carinata (Bbcc) and black‐seeded B. napus (AACC). Three different interspecific crossing approaches were undertaken. Approaches 1 and 2 were designed directly to develop yellow‐seeded B. napus while approach 3 was designed to produce a yellow‐seeded CC genome species. Approaches 1 and 2 differed in the steps taken after trigenomic interspecific hybrids (ABC) were generated from B. carinata×B. rapa crosses. The aim of approach 1 was to transfer the yellow seed colour genes from the A to the C genome as an intermediate step in developing yellow‐seeded B. napus. For this purpose, the ABC hybrids were crossed with black‐seeded B. napus and the three‐way interspecific hybrids were self‐pollinated for a number of generations. The F7 generation resulted in the yellowish‐brown‐seeded B. napus line, No. 06. Crossing this line with the B. napus line No. 01, resynthesized from a black‐seeded B. alboglabra x B. rapa var.‘yellow sarson’ cross (containing the yellow seed colour genes in its AA genome), yielded yellow‐seeded B. napus. This result indicated that the yellow seed colour genes were transferred from the A to the C genome in the yellowish‐brown seed colour line No. 06. In approach 2, trigenomic diploids (AABBCC) were generated from the above‐mentioned trigenomic haploids (ABC). The seed colour of the trigenomic diploid was brown, in contrast to the yellow seed colour of the parental species. Trigenomic diploids were crossed with the resynthesized B. napus line No. 01 to eliminate the B genome chromosomes, and to develop yellow‐seeded B. napus with the AA genome of ‘yellow sarson’ and the CC genome of B. carinata with yellow seed colour genes. This interspecific cross failed to generate any yellow‐seeded B. napus. Approach 3 was to develop yellow‐seeded CC genome species from B. alboglabra×B. carinata crosses. It was possible to obtain a yellowish‐brown seeded B. alboglabra, but crossing this B. alboglabra with B. rapa var.‘yellow sarson’ failed to produce yellow seed in the resynthesized B. napus. The results of approaches 2 and 3 demonstrated that yellow‐seeded B. napus cannot be developed by combining the yellow seed colour genes of the CC genome of yellow‐seeded B. carinata and the AA genome of ‘yellow sarson’.
Identification of microsatellite polymorphisms in an expressed portion of the rye genome
Authors: Hackauf B. , Wehling P.
Published: March 2003

For the purposes of genetics and application the number of simple sequence repeat (SSR) markers in rye has to be increased significantly to cover the entire genome. To this end, more than 8000 publicly accessible rye cDNA sequences from anthers, cold‐stressed leaves, and aluminium‐stressed and unstressed roots were exploited as a resource for SSR marker development. A total of 157 Secale cereale micro‐satellite (SCM) loci out of 528 SSRs comprising di‐, tri‐ and tetra‐nucleotide motifs could be assayed on automated sequencers. One‐hundred expressed sequence tag (EST)‐derived SCM loci displayed a length polymorphism among a sample of 15 rye accessions. Of the SCM, 45% could be associated with proteins of known or unknown function. Recently published ESTs from different rye tissues proved to be a valuable resource for SSR marker development in rye.
Amplified fragment length polymorphism‐ and simple sequence repeat‐based molecular tagging and mapping of greenbug resistance gene Gb3 in wheat
Authors: Weng Y. , Lazar M. D.
Published: March 2003

The greenbug, Schizaphis graminum (Rondani), is the most economically damaging aphid pest of wheat in the southern Great Plains of the USA. In this study, the single, dominant greenbug resistance gene, Gb3, was molecularly tagged and genetically mapped using amplified fragment length polymorphism (AFLP) and simple sequence repeat(SSR) markers. Three AFLP loci were associated with the Gb3 locus in linkage analysis with 75 F2:3 families from the cross between two near‐isogenic lines (NILs) for Gb3,‘TXGBE273’ and ‘TXGBE281′. Two of these loci, XMgcc Pagg and Xmagg Patg cosegregate with Gb3 in the population analysed. Further analysis indicated that XMgcc Pagg and Xmagg Patg are specific for the Gb3 locus in diverse genetic backgrounds. Two SSR markers, Xgwm111 and Xgwm428 previously mapped in wheat chromosome 7D, were shown to be linked with Gb3, 22.5 cM and 33.1 cM from Gb3, respectively, in an F2 population of ‘Largo’×‘TAM 107’, suggesting that Gb3 is located in the long arm of chromosome 7D. The two AFLP markers cosegregating with Gb3 are valuable tools in developing molecular markers for marker‐assisted selection of greenbug resistance in wheat breeding.
Genetic characterization of spontaneous diploid androgenetic wheat and triticale plants
Authors: Muranty H. , Sourdille P. , Bernard S. , Bernard M.
Published: March 2003

The homozygosity of spontaneous hexaploid plants derived from anther culture was evaluated in wheat and triticale by means of 18 and 22 microsatellite markers, respectively. Most of the spontaneous hexaploid plants were homozygous for all the loci tested and had chromosomes recombining for parental alleles. Only 12% of the spontaneous hexaploid wheat plants, 11% of the artificially doubled wheat plants and 4.4% of the spontaneous hexaploid triticale plants were heterozygous at one to three of the loci studied. This showed that spontaneous hexaploid plants mostly came from normal haploid cells, obtained after meiosis, that underwent spontaneous chromosome doubling. However, first or second division restitution, producing unreduced gametes, cannot be completely excluded to explain the origin of the spontaneous hexaploid plants. Cytomixis, involving only one chromosome, or development of aneuploid trisomic gametes, followed by chromosome doubling for the spontaneous hexaploid plants, or transposition events could also explain some of the results obtained.
Studies on resistance to bacterial speck (Pseudomonas syringae pv. tomato) in tomato cv. Ontario 7710
Authors: Kozik E. U.
Published: March 2003

Plants of 17 tomato cultivars and four wild Lycopersicon accessions were evaluated for their reaction to Pseudomonas syringae pv. tomato (Pst) in a greenhouse following a leaf‐spray inoculation. The genotypes exhibited a large amount of variation in response to Pst infection, with disease severity index (DSI) ratings from 0.2 to 3.9. The cultivar ‘Ontario 7710’ and two accessions of Lycopersicon hirsutum (LA 1773 and LA 1775) were the most resistant, with DSI values of 0.2, 0.4 and 0.6, respectively. Three varieties, M 1812, Kujawski and Warszawski, also showed a high level of tolerance. The most susceptible was ‘A 100’(DSI = 3.9).

The inheritance of resistance to bacterial speck was investigated by disease tests in segregated populations obtained by hybridizing the tomato cv. Ontario 7710 with the susceptible variety ‘A 100′. Plants were rated for disease severity by inspecting each plant and were then evaluated according to phenotypic similarity to ‘Ontario 7710’ or ‘A 100’ in respect of the number and size of the spots. Genetic analysis in F1, F2 and backcross segregations indicated that resistance of'Ontario 7710’ to Pst is conferred by one incompletely dominant gene, Pto.
Inheritance of resistance of wheat to eyespot at the adult stage
Authors: Muranty H. , Jahier J. , Tanguy A.‐M. , Worland A. J. , Law C.
Published: March 2003

Moderate resistance to eyespot was first incorporated in the variety Cappelle‐Desprez (CD). Later the gene Pch1, which could confer a higher level of resistance, was introduced from Aegilops ventricosa. However Pch1‐carrying varieties can sustain significant eyespot‐induced yield losses in severe attack situations. A strategy to further enhance the resistance of wheat is by pyramiding Pch1 and the genes for resistance in CD. The first requirement to achieve this is a better understanding of the genetics of resistance in CD. The resistance of the 21 Cappelle‐Desprez (Bezostaya) disomic substitution lines was evaluated. Chromosome 7A was confirmed as carrying a major gene for resistance to eyespot at the seedling stage. However, this study demonstrates that this chromosome has no effects at the adult stage. Chromosome 5A was shown to carry a major gene for resistance to eyespot at the adult stage, which was stably expressed each year of testing. Chromosomes 1A and 2B had significant effects for only two years among four.
Effect of genome composition and cytoplasm on petal colour in resynthesized amphidiploids and sesquidiploids derived from crosses between Brassica rapa and Brassica oleracea
Authors: Zhang B. , Lu C. M. , Kakihara F. , Kato M.
Published: March 2003

The effect of genome composition and cytoplasm on petal colour was studied in Brassica. Three accessions of yellow‐petalled B. rapa (2n= 20, AA) were crossed with a white‐petalled B. oleracea var. alboglabra (2n= 18, CC) and with three cream‐yellow‐petalled B. oleracea var. gongylodes (2n= 18, CC) to produce resynthesized B. napus (2n= 38, AACC or CCAA) and sesquidiploids (2n= 29, AAC or CAA). Petal colour was measured with a Hunter automatic colour difference meter. The results revealed that petal colour in Brassica is controlled by nuclear genes and by cytoplasmic factors. Additive and epistatic gene effects were involved in the action of nuclear genes. When crosses were made between yellow‐petalled B. rapa and white‐petalled B. oleracea var. alboglabra, significant additive, epistatic and cytoplasmic effects were found. White petal colour was partially epistatic over yellow petal colour. When crosses were made between yellow‐petalled B. rapa and cream‐yellow‐petalled B. oleracea var. gongylodes, only epistatic effects were detected. Yellow petal colour was epistatic over cream‐yellow.
Use of component analysis in QTL mapping of complex crop traits: a case study on yield in barley
Authors: Yin X. , Chasalow S. D. , Stam P. , Kropff M. J. , Dourleijn C. J. , Bos I. , Bindraban P. S.
Published: March 2003

Genes contributing to the quantitative variation of a complex crop trait can be numerous. However, using existing approaches, the number of quantitative trait loci (QTL) detected for a trait is limited. Therefore, rather than looking for QTL for a complex trait itself, determining QTL for underlying component traits might give more information. In this study the potential of component analysis in QTL mapping of complex traits was examined using grain yield in spring barley as an example. Grain yield was divided into three components: number of spikes/m2, number of kernels/spike, and 1000‐kernel weight. These traits were measured for individuals of a recombinant inbred‐line population in field trials conducted over 2 years. By the use of an approximate multiple QTL model, one to eight QTL were detected for each trait in a year. Some QTL were mapped to similar positions in both years. Almost all QTL for yield were found at the position of or in close proximity to QTL for its component traits. A number of QTL for component traits were not detected when yield itself was subjected to QTL analysis. However, relative to the QTL for yield itself, all component‐trait QTL did not explain the variation in yield better. The results in relation to the potential of using component analysis in studying complex crop traits are discussed.
Inheritance of calyx shape in the genus Origanum (Lamiaceae)
Authors: Novak J. , Gimplinger D. , Franz Ch. , Grunewaldt J.
Published: March 2003

Five different traits responsible for calyx shape within the genus Origanum were found to be determined by five independent genes. The five traits are bell‐shaped vs. tubular‐shaped calyx, angular vs. round teeth on the upper lip, entire vs. denticulate upper lip, fully developed vs. reduced lower lip and entire vs. denticulate lower lip. The simple Mendelian inheritance of most traits for calyx shape could be used to identify hybrids between Origanum species arising from open‐pollinated plants and so avoid tedious artificial pollination resulting from small flower sizes in Origanum. Such hybrids are interesting base material for character transfer (e.g. winter hardiness or seed size) between economically important species.
Amplified fragment length polymorphism‐derived microsatellite sequence linked to the Pch1 and Ep‐D1 loci in common wheat
Authors: Groenewald J. Z. , Marais A. S. , Marais G. F.
Published: March 2003

Amplified fragment length polymorphism (AFLP) markers linked to the Aegilops ventricosa‐derived chromosome segment in ‘VPM1’ on which the eyespot resistance gene, Pch1, and the endopeptidase gene, Ep‐D1b, occur were identified. One marker was isolated from the gel, cloned and sequenced. Sequence analysis revealed a microsatellite repeat motif. Sequence‐specific primers were designed to amplify a product containing the repeat motif, and the microsatellite marker was tested for cosegregation with the Ep‐D1b allele. Distinct alleles were produced by the Pch1 sources, normal wheat and wheat containing the Lr19 translocation. A recombination frequency of 0.02 was calculated between the microsatellite marker and Ep‐D1.
Review of the Results of Common Carp (Cyprinus carpio) Breeding at a Large‐Scale Hatchery
Authors: Szabo T , Szabo R , Urbanyi B , Horvath L
Published: March 2003

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Long‐term data on the induced spawning of common carp (Cyprinus carpio) at a large‐scale hatchery were evaluated. Breeders at the farm prefer medium‐size fish with body weights between 4 and 8 kg. The number of females selected for propagation in the first period of the spawning season made up about half of the total number of females (47.5%). The average spawning ratio from the data of 2620 females receiving hormonal injections was 79.8%. From the egg production data of 2086 females, the average pseudogonadosomatic index (PGSI) was calculated as 16.3 ± 5.87% (mean ± SD) for the same period. There was a high correlation between fish weight and the time of induction, determined by the breeder on the basis of secondary sexual characteristics. The similarity of the responses of females among the different weight categories proved the reliability of this method for identification. The time of induction has a significant effect on both the responsiveness of the females and the relative quantity of eggs released. Spawning ratio was significantly lower in the third period of the reproductive season, compared with those in the first and second period. Mean PGSIfor the third period was significantly lower than that for the first period. The considerable decrease of both reproductive parameters by the end of the spawning season is attributed to ovarian atresia. The spawning ratio and the mean PGSIfor the mirror and scaled varieties were similar.
Activation of Pig Oocytes using Calcium Ionophore: Effect of the Protein Kinase Inhibitor 6‐dimethyl aminopurine
Authors: Jílek F , Hüttelová R , Petr J , Holubová M , Rozinek J
Published: March 2003

The aim of our study was to investigate the parthenogenetic activation of in vitro matured pig oocytes after their combined treatment with calcium ionophore A 23187 and the inhibitor of protein kinases, 6‐dimethylaminopurine (6‐DMAP) and to study the further embryonic development of oocytes activated using this treatment. The oocytes were exposed to ionophore (10, 25 or 50 μM) for 0.5, 1, 3, 5 or 7 min and then cultured with 6‐DMAP (0 or 2 μM) The highest activation rate (up to 88% of the activated eggs reached the pronuclear stage) was observed after combined treatment of the oocytes with 50 μM ionophore and 6‐DMAP. The highest rate of embryonic development was observed after treatment with 25 μM ionophore without 6‐DMAP, when up to 51% of the eggs developed beyond two‐cell stage, 2% of the eggs developed up to the stage of morula and up to 3% of the eggs reached the stage of blastocyst. When 50 μM ionophore was used, the embryonic development of the activated eggs was arrested before the morula and blastocyst stage. After treatment of the activated eggs with 6‐DMAP, we did not observe any development beyond the stage of 16 blastomeres. We can conclude that combined treatment with calcium ionophore A 23187 and 6‐DMAP increases the activation rate in pig oocytes matured in vitro, but this combined treatment exerts a detrimental effect on further embryonic development of the activated eggs.
Effectiveness of Cabergoline for Termination of Pregnancy in Silver Fox (Vulpes vulpes fulva)
Authors: Lengwinat T , Meyer HHD , Jöchle W
Published: March 2003

Red foxes (Vulpes vulpes) are a major pest species in Europe and Australia. Traditional methods of control such as hunting or poisoning are no longer sufficient or feasible. As with domestic dogs and cats, prolactin (PRL) in the vixen is an essential luteotropin during the second half of gestation. Hence, PRL inhibitors such as cabergoline have been used to induce abortions. Eighteen mated silver fox vixens (three groups of six foxes each) were treated orally with a placebo of paraffin oil (I), or with 15 μg/kg cabergoline in feed once (II) or twice (III), on day 30 (I and II) or days 30 and 32 (III) post‐coitum. Blood samples were taken prior to and after treatments and concentrations of PRL and progesterone (P4) were determined. Normal parturitions were observed in five of six, five of six and two of six vixens in groups I, II and III, respectively. In group III plasma concentrations of PRL and P4 decreased significantly but only temporarily. This drop in hormone concentrations was more pronounced in the vixens that did not carry to term. In conclusion, doses in excess of 15 μg/kg of cabergoline are likely to prevent the development of fetuses to term in pregnant vixens.
Litter Size and Vagina–cervix Catheter Penetration Length in Gilts
Authors: Rillo S Martín , Romero C de Alba , Rodriguez A Romero , Cidoncha R , Ziecik AJ
Published: March 2003

As in other species, the reproductive tract in pigs increases in size with age and body weight, and the development of the reproductive tract depends on a balance between development of the pituitary–ovarian axis and the influence of metabolic hormones. Two experiments were conducted in prepubertal Duroc gilts, 150–180 days of age, to determine whether litter size is related to vaginal–cervix catheter penetration length during insemination. In experiment 1, oestrus was induced in 452 gilts with a combined dose of 400 IU Pregnant Mare Serum Gonadotrophine (PMSG) + 200 IU human chorionic gonadotropin (hCG). The gilts were classified into three catheter penetration length groups: Ih, ≤ 21 cm; IIh, > 21 and < 28 cm; IIIh, > 28 cm. The litter size was lowest in group Ih (7.35 ± 0.15) compared with groups IIh (7.81 ± 0.12; p < 0.05) and IIIh (10.0 ± 0.36; p < 0.001). In experiment 2, first oestrus was induced in 162 gilts by boar exposure. The gilts were classified into three catheter penetration length groups at insemination during their second oestrus: In, ≤ 24 cm; IIn, > 24 and < 26 cm; IIIn, > 26 cm. As in experiment 1, the litter size was lowest in the group with the shortest catheter penetration length (8.32 ± 0.19). The litter size was not different among gilts of groups IIn and IIIn (8.84 ± 0.35 and 9.56 ± 0.46, respectively), but litter size was lower (p < 0.05) in group In than in group IIn. Based on the combined data from both experiments, the correlation between the catheter penetration length and total number of piglets born was expressed as: y=5.346 ± 0.104x; r=0.361 (p < 0.05). Fertility rate was not different among the groups of gilts induced into oestrus by hormone treatment or inseminated in the second oestrus; however, the total fertility rate of boar‐exposed gilts was higher (p < 0.0001) than PMSG/hCG treated animals. Thus, it is possible to conclude that litter size at first farrowing is associated with vaginal–cervix catheter penetration length during insemination of the gilt.
Reproductive Parameters and Efficiency of Inseminators in Dairy Farms in Portugal
Authors: Rocha A , Rocha S , Carvalheira J
Published: March 2003

This study was carried out to determine the reproductive efficiency indices of one of the largest dairy co‐operatives of northern Portugal, using data from 1980 to 1998. Records were made available by the computerized National Recording System. Age at first calving was 32.0 ± 6.0 months. Mean calving to first AI interval was 95.4 ± 30.0 days, and calving to conception intervals decreased (p < 0.05) from 176.9 ± 4.5 to 148.1 ± 5.6 days from the first to the fourth/fifth parturitions, respectively. Calving intervals decreased (p < 0.05) from 418.1 ± 3.4 to 392.5 ± 7.0 days from the first to fourth/fifth parturitions, respectively. Mean non‐return rates at 90 days for first inseminations was 71.7 ± 6.5% and mean calving rates at first insemination was 51.4 ± 8.1%. There were significant differences (p < 0.001) in the inseminators’ efficiency, measured by both non‐return and calving rates at first AI, with differences between the best and worst results of 13.3 and 16.1% for non‐return and calving rates, respectively. The ranking of the inseminators did not coincide when their efficiency was measured by either non‐return or calving rates. The mean number of inseminations per pregnancy (pregnant cows only) was 1.4 ± 0.7 with significant (p < 0.001) differences among herds. The mean heat detection rate was 38.1 ± 16.9%, with highly significant (p < 0.001) differences among farms (ranging from 14.2 to 60.8%). Negative (p < 0.001) correlations were found between heat detection rate and calving to first AI, calving to conception and calving intervals. The meaning of these indexes for assessment of reproductive efficiency in the studied system, is discussed.
Comparison of the Ability of Three Radioimmunoassay to Detect Pregnancy‐associated Glycoproteins in Bovine Plasma
Authors: Perényi ZS , Szenci O , Sulon J , Drion PV , Beckers JF
Published: March 2003

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Pregnancy‐associated glycoproteins (PAGs) constitute a large family of glycoproteins that are synthesized in the superficial layer of the ruminant placenta according to a spatial and temporal expression pattern. When PAGs are released in the maternal blood they can be used for pregnancy diagnosis, pregnancy follow‐up and for the monitoring of the trophoblastic function. Three different radioimmunoassay systems (RIA 1, RIA 2 and RIA 3) using antisera produced against PAG I67 (RIA 1), PAG55+62 (RIA 2) and PAG55+59 (RIA 3) were used in this investigation in order to measure the PAG concentration in plasma samples withdrawn from pregnant cows and heifers during different periods following artificial insemination (AI). These systems were able to detect PAG molecules in the maternal blood as early as 21 days after AI in different concentrations (RIA 1: 0.43 ± 0.24 ng/ml, mean ± SD; RIA 2: 0.48 ± 0.24 ng/ml; RIA 3: 0.64 ± 0.37 ng/ml). On days 32 and 42 RIA 2 (4.30 ± 1.32 ng/ml and 5.56 ± 1.95 ng/ml) and RIA 3 (4.17 ± 1.15 ng/ml and 5.60 ± 1.89 ng/ml) presented significantly (p < 0.0001) higher PAG concentrations than those of RIA 1 (2.43 ± 0.81 ng/ml and 4.01 ± 1.48 ng/ml), respectively. After day 21, significant correlations (p < 0.0001; r ≥ 0.929) were determined between the three systems. Additionally the three individual PAG profiles presented in this study showed that PAG molecules secreted in the maternal blood between 21 and 50 days after AI were better recognized by the RIA 2 and RIA 3 systems. This study clearly indicated that the ability of a RIA test to recognize PAG molecules in the maternal blood can be improved by carefully selecting the antiserum.
Cell‐specific Distribution of Oestrogen Receptor‐alpha in the Bovine Ovary
Authors: Van Den Broeck W , Coryn M , Simoens P , Lauwers H
Published: March 2003

Contents

In this study, the expression of estrogen receptor alpha (ERα) in the bovine ovary is described. ERα was visualized by immunohistochemistry on paraffin sections of ovaries obtained from 11 non‐pregnant and 2 pregnant animals. In general, ERα was not observed in cells of primordial, primary and secondary follicles, whereas weak expression was noticed in cells of healthy and arteric tertiary follicles. In corpora lutea cells the expression of ERα was obvious. Intermediate to high ERα expression was present in thecal cells and in cells of the superficial and deep stroma, tunica albuginea and surface epithelium. Furthermore, the expression of ERα in stroma and tunica albuginea cells was in general, highest in cows with the lowest plasma progesterone levels, and lowest in cows with the highest plasma progesterone levels. Remarkably, the ERα expression in pregnant cows was in general, lower than in non‐pregnant cows with similar plasma progesterone levels. The relatively high expression of ERα in thecal and stromal cells in comparison with that in follicle cells suggests an indirect effect of estrogen on the follicular development. However, the exact function of ERα in the bovine ovary together with the cycle‐dependent variations in ERα expression remain to be elucidated.
Effects of VEGF and bFGF on Proliferation and Production of Steroids and Nitric Oxide in Porcine Granulosa Cells
Authors: Grasselli F , Basini G , Bussolati S , Tamanini C
Published: March 2003

Contents

Ovarian angiogenesis, which is currently considered to be of crucial importance in controlling the growth of developing follicles, is a physiological process driven by a variety of angiogenic factors. Among these, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) have been recognized as key players in promoting cell growth and differentiation. Porcine granulosa cells from small (<3 mm), medium (3–5 mm) and large (>5 mm) follicles were seeded at different densities in DMEM:Ham's F12 (1:1) with or without different concentrations of VEGF or bFGF. After 48 h of culture, media were assayed for oestradiol (E2) 17β, progesterone (P4), nitric oxide (NO) and VEGF levels; in addition, cell proliferation was evaluated by 3H‐thymidine incorporation assay. Both bFGF and VEGF effects on E2 and P4 production by cultured granulosa cells resulted to be dependent on follicle size. The bFGF was always ineffective in modulating cell proliferation, while VEGF exerted an inhibitory effect on the proliferation in the small follicle group and a stimulatory one in the medium and large follicle groups. The bFGF consistently reduced NO levels in culture media. The VEGF appeared to be ineffective in modifying NO production in the small follicle group, while it was stimulatory in the medium follicle group and inhibitory in the large follicle group. Basal VEGF production was higher in cells from the large follicle as compared with the small and medium follicle groups, and it was unaffected by bFGF. These results suggest that VEGF plays a modulatory role in granulosa cell functional activity and it is possibly involved in the regulation of follicle growth; on the contrary, bFGF does not appear to represent a significant regulatory factor in our cellular model, except for an inhibitory action on the production of NO, whose anti‐angiogenic properties need to be further substantiated.
Effects of Ram Introduction After the Second Prostaglandin F2α Injection on Day 11 on the LH Surge Characteristics in Fat‐Tailed Ewes
Authors: Yildiz S , Saatci M , Uzun M , Güven B
Published: March 2003

Contents

The aim of this study was to evaluate the effects of ram introduction after the second prostaglandin F2α (PG F2α) injection on day 11 on the secretion characteristics of pre‐ovulatory LH surge of fat‐tailed ewes. Multiparous Morkaraman ewes (n=12) were divided into three groups by balancing the groups for liveweight (BW) and body condition score (BCS). On the day of second PGF2α injection (0 h), performance tested rams (n=2) were either introduced to the ewes at 0 h (ram 0 group, n=4) or at 18 h (ram 18 group, n=4) or were not introduced (control group, n=4). Blood samples were collected at 6, 18, 42, 48, 56, 62, 66, 70, 74, 78 and 90 h for the determination of pre‐ovulatory LH surge. BCS and BW during the experimental period were 2.2 ± 0.2 units and 50.9 ± 2.3 kg, 2.4 ± 0.4 units and 49.2 ± 6.2 kg, 2.1 ± 0.3 units and 45.9 ± 4.4 kg, respectively for the ram 0, ram 18 and control groups (p > 0.05). No significant difference was observed in LH surge characteristics for the experimental groups. Peak LH concentrations were also not different between groups (p > 0.05) and they were 12.2 ± 8.3, 29.1 ± 9.9 and 15.8 ± 9.5 μg/l for the ram 0, ram 18 and control groups, respectively. There was, however, a significant correlation between peak LH concentrations and BCS (p < 0.05, R2=0.373). In conclusion, it appears that, compared with ram introduction, variability in body condition of the ewe has much pronounced effect on the amount of LH secreted after the usage of two PGF2α injections (11 days apart) as a tool for oestrus synchronization.
Multiple family group interventions in first episode psychosis: Enhancing knowledge and understanding
Authors: Mullen Antony , Murray Linda , Happell Brenda
Published: March 2003

ABSTRACT:

Families play a major role in promoting recovery and preventing relapse following the first psychotic episode. This paper presents a multiple family group education programme for the families of clients with first episode psychosis. The educational needs of the families are also discussed. The results of this evaluation show that the programme improved the families’ perceptions of their overall knowledge and understanding of mental illness and its treatment. This evaluation demonstrates the efficacy of such groups and the key role of community mental health nurses in providing family interventions.
Through the eye of the beholder: To seclude or not to seclude
Authors: Wynaden Dianne , Chapman Rose , McGowan Sunita , Holmes Colin , Ash Pauline , Boschman Antonius
Published: March 2003

ABSTRACT:

The objective of this study is to provide new knowledge and understanding of the decision making used throughout the seclusion process. Seven mental health nurses and one doctor were each interviewed within 48 hours of making the decision to seclude a patient. The interviews were analysed using content analysis. This study provides valuable information regarding factors that are central to, and/or influence, the decision‐making process surrounding seclusion. More importantly, the results demonstrate that seclusion is initiated only when all other less restrictive patient management strategies have proven to be unsuccessful with the patient.
Characteristics of the delta formation resulting from sediment deposition in Lake Nasser, Egypt: Approach to tracing lake delta formation
Authors: El‐Manadely M. S. , Abdel‐Bary R. M. , El‐Sammany M. S. , Ahmed T. A.
Published: March 2003

A major problem encountered by managers of large reservoirs, such as Lake Nasser (located in the south of Egypt), is the continuous deposition of sediments, resulting in a bed‐level increase, a decrease in lake capacity, and the creation of a new delta that might eventually hinder navigation. To investigate the sedimentation problem in Lake Nasser, a series of surveyed cross‐sections were reviewed and samples of suspended sediment and bed material collected. These sets of data were analysed to investigate the progress of the delta formation, the change in its properties in all directions and the corresponding patterns of suspended and deposited sediment particles. Results showed that deposited sediments, characterized by a variable pattern of particle composition, are building up at the lake entrance. Although the expansion of the delta is multidirectional, its accelerated advance towards the High Aswan Dam would depend on the frequent occurrence of high floods following extended drought periods. Based on the calculated deposited sediment volume in Lake Nasser during the period 1964–1998, the lifetime of the dead storage zone allocated for sediment deposition (31 × 109 m3) is estimated at a minimum of 310 years.
Sex‐determined resistance against Leishmania mexicana is associated with the preferential induction of a Th1‐like response and IFN‐γ production by female but not male DBA/2 mice
Authors: Satoskar Abhay , Al‐Quassi Hamid Herrata Khamis , Alexander James
Published: March 2003

Female DBA/2 mice are relatively resistant to infection with Leishmania mexicana compared with male mice. Following subcutaneous infection with 5 × 106 L. mexicana, amastigotes lesion growth in male and female DBA/2 mice was measured and the developing immune responses were monitored both in vitro and in vivo. Over the 10 week duration of the experiment all male DBA/2 mice developed rapidly growing non‐healing lesions while female mice either developed no lesions whatsoever or developed smaller slower growing lesions than males. Both male and female mice produced parasite specific IgG2a during the course of the disease. However, significant titres of parasite specific IgG1 antibodies could be detected only in male mice indicating a Th2‐influenced response in this sex. Furthermore, female mice, unlike male mice, developed significant parasite induced cutaneous delayed‐type hypersensitivity footpad responses, indicating a Th1‐influenced response in female mice. Although both male and female DBA/2 mice infected with L. mexicana displayed a significant increase in the number of cells in their draining lymph nodes at week 10 post‐infection, no significant differences could be observed in the numbers of CD4+, CD8+ T cells as well as B cells between male and female DBA/2 mice. However, following in vitro stimulation, the lymph node cells from female mice displayed significantly higher antigen specific proliferative responses than the males and produced significant amounts of IFN‐γ which could not be detected in the equivalent culture supernatants from male mice. There were no significant differences in the levels of Th2‐associated cytokines IL‐4 and IL‐5, produced by the lymph node cells of both sexes. Treatment of female DBA/2 mice with IFN‐γ neutralizing antibody following L. mexicana infection resulted in lesion growth equivalent to male mice. Conversely, intralesional injections of murine recombinant IFN‐γ significantly inhibited lesion growth in male mice.
Retrograde axonal transport of neurotrophins: Differences between neuronal populations and implications for motor neuron disease
Authors: Bartlett Selena E , Reynolds Anna J , Hendry Ian A
Published: March 2003

During development, neurons die if they do not receive neurotrophin support from the target cells they are innervating. Neurotrophins are delivered from the target to the cell bodies of the innervating neurons by interacting with specific receptors located on the nerve terminals and then together are retrogradely transported to the cell body. This process consists of a number of distinct events including endocytosis of neurotrophin and its receptor into coated vesicles; vesicle sorting followed by retrograde axonal transport to the cell body, where interaction of the activated receptor initiates a signalling cascade at the cell body that causes the survival response. It has recently been shown that the signalling molecules associated with retrograde transport differ between neuronal populations. In sympathetic but not sensory neurons, a wortmannin‐sensitive molecule (phosphatidylinositol kinase) is essential for the retrograde transport of neurotrophins. In sensory but not sympathetic neurons, a rapamycin‐sensitive molecule (pp70S6K) is associated with retrograde transport of neurotrophins. This is strong evidence that sympathetic and sensory neurons utilize different signalling pathways to perform the same cellular function; retrograde transport. These findings may provide clues to understanding neurological diseases, such as motor neuron disease, in which axonal transport is impaired specifically in motor neurons.
Kinetics of inflammatory cytokines in the clearance of non‐typeable Haemophilus influenzae from the lung
Authors: Foxwell A Ruth , Kyd Jennelle M , Cripps Allan W
Published: March 2003

Levels of the pro‐inflammatory cytokines TNF‐α and IFN‐γ were measured from the time of infection to the time of complete clearance of non‐typeable Haemophilus influenzae (NTHi) from the lung in immune and non‐immune rats. Mucosal immunization facilitated production of significant levels of TNF‐α as early as 30 min post‐pulmonary challenge with NTHi in immune animals. Following the peak at 2 h, rapid decline of TNF‐α levels occurred from the alveolar spaces. Levels of TNF‐α in non‐immunized animals increased at a slower rate, peaked at a lower concentration and were slower to decline. The significantly larger number of macrophages seen in the immune animals at 1 h after bacterial challenge could partially account for the higher levels of TNF‐α. Interferon‐γ was not detected in immune or non‐immune rats at any time point before NTHi clearance after pulmonary challenge. Study of the kinetics of TNF‐α release demonstrates that immunized animals control the release of pro‐inflammatory cytokines more effectively than non‐immunized animals for enhanced clearance of bacterial infection from the lungs.
The logic of intercellular communication in the immune system
Authors: Hodgkin PD , Rush J , Gett AV , Bartell G , Hasbold J
Published: March 2003

The collaboration between T and B lymphocytes is used as an example to illustrate how the key features of immune regulation (cell interaction, reciprocal exchange of signals by cell contact, and dependence on soluble cytokines) serve as amplifying reactions. By linking cell‐based amplifiers in sequence, the resulting immune response is made highly sensitive to small changes in the environment. Thus, intercellular communication in the immune system can be viewed as a higher level analogue to the kinase cascades that amplify intracellular signalling mechanisms.