Natural diversity of inflorescence architecture traces cryptic domestication genes in barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.)     

Helmy M. Youssef  Martin Mascher  Mohammad A. Ayoub  Nils Stein  Benjamin Kilian  Thorsten Schnurbusch 《Genetic Resources and Crop Evolution》2017,64(5):843-853

Many-grained mutants occurring spontaneously among their less well-endowed field mates may have appeared to early farmers as fortunate twists of fate foreboding wealth and abundance. In domesticated barley, the number of kernel rows in spike can be tripled by recessive mutant alleles at the Six-rowed spike 1 (vrs1) locus that abolish the suppression of lateral spikelet fertility. In another barley row-type, so called intermedium-spike (int), lateral floret size is often intermediate between six-and two-rowed types. Phenotypic and sequence analyses of our intermedium-spike collection revealed that other genes can increase the size of florets and even stimulate occasional grain setting in lateral spikelets. Here, we show that a complete six-rowed phenotype occurs in a diverse panel of intermedium-spike barley carrying wildtype Vrs1 in the presence of the Int-c.a allele of the intermedium spike-c (int-c) gene, previously considered only as a modifier of lateral spikelet fertility. Int-c.a-type alleles had arisen before domestication and are associated with the enlargement of lateral florets in wild barley, suggesting that natural selection/evolution acts towards reduced lateral floret size. Since Int-c.a cannot overcome the suppression of lateral florets in the genomic background of wild barleys, we infer the existence of other gene loci, at which novel alleles or allelic combinations were selected for after domestication, to increase grain number of barley independently of Vrs1.  相似文献   

Relationships between Early Foal Health,Future Performance and Their Dams Reproductive Health     

E Hemberg  H Kindahl  N Lundeheim  S Einarsson 《Reproduction in domestic animals》2010,45(5):817-820

The objectives of this study were to investigate: (i) relationships between early foal health and their dams’ reproductive health at mating/conception as well as after parturition and (ii) health status during early foal life and its association with performance as an adult. The study included 35 foals showing clinical symptoms indicating septicaemia, sometimes in combination with other disturbances, within their first 18 h postpartum (Group I). Eighty‐eight foals that were healthy during their first few days of life were used as control (Group II). All foals were born in the same region of Sweden and during the same period, and were expected to become performance athletes based upon the pedigree of their parents. Cytological and bacteriological examination of uterus at the time of mating/insemination at which the foal was conceived, revealed no difference between dams of Group I and Group II foals. Within 2–3 days after parturition, 29% and 4% of dams (p < 0.001) of Group I and Group II foals had metritis, respectively. At 30 days post‐parturition, 64% of the dams of Group I foals and 32% of the dams of Group II foals (p = 0.002) had cytological indication of endometritis, and 57% of the dams of Group I foals and 21% of the dams of Group II foals (p < 0.001) showed bacterial growth upon culture. Altogether 29% of the Group I foals and 7% of the Group II foals were killed or died before 2 years of age (p = 0.001). The majority of the remaining Group I foals were poor performers and some were used just for pleasure riding. It is hypothesized that (i) mares – delivering foals that compromised within their first 18 h postpartum – might have suffered from an ascending infection during late gestation and (ii) health status during early foal life might be associated with their performance as adult.  相似文献   

Different crop rotation systems as drivers of change in soil bacterial community structure and yield of rice, <Emphasis Type="Italic">Oryza sativa</Emphasis>     

Do?Thi?XuanEmail author  Vo?Thi?Guong  Anna?Rosling  Sadhna?Alstr?m  Benli?Chai  Nils?H?gberg 《Biology and Fertility of Soils》2012,48(2):217-225

Intensive cropping, especially of rice, is considered to contribute to negative effects not only on soil chemical and biological properties but also on long-term grain yield. Appropriate crop rotation is often practiced as an alternative strategy to overcome the negative side effects of intensive cropping. Although soil microbial diversity and community structure have been shown to respond differently to altered agricultural management practices, little is known about possible links between crop rotation and grain yield on bacterial communities in rice paddy soil. In this study, we investigated the impact of specific rotational crops and compared it with intensive rice cultivation. The main crop rice (Oryza sativa) was rotated with maize (Zea mays) and mungbean (Phaseolus aureus) in different combinations in a system cultivating three crops per year. Soil bacterial communities were studied in two different cropping periods using pyrosequencing of the variable V4 region of the 16S rRNA. Our results showed that rotation with alternative crops increased rice yield by 24–46% depending on rotation structure and that bacterial community structure was altered in the presence of mungbean and/or maize compared to that in rice monoculture. In the crop rotation systems, composition, abundance, and diversity of soil bacterial communities were significantly different and higher than those in rice monoculture. Our results show that effects of crop rotation relate to changes in soil bacterial community structure suggesting that appropriate crop rotations provide a feasible practice to maintain the equilibrium in soil microbial environment for sustainable rice cultivation.  相似文献   

Associations between the time of conception and the shape of the lactation curve in early lactation in Norwegian dairy cattle     

Fredrik Andersen  Olav ?ster?s  Olav Reksen  Nils Toft  Yrjo T Gr?hn 《Acta veterinaria Scandinavica》2011,53(1):5

Background

This study was carried out to determine if an association exists between the shape of the lactation curve before it is influenced by the event of conception and the time from calving to conception in Norwegian dairy cattle. Lactation curves of Norwegian Red cows during 5 to 42 days in milk (DIM) were compared between cows conceiving between 43 and 93 DIM and cows conceiving after 93 DIM.

Methods

Data from 23,049 cows, represented by one lactation each, with 219,538 monthly test days were extracted from the Norwegian Dairy Herd Recording System, which represents 97% of all Norwegian dairy cows. Besides veterinary treatments, these records also included information on daily milk yield at monthly test days. The data were stratified by parity groups (1, 2, and 3 and higher) and time to conception periods (43-93 DIM and >93 DIM). The sample was selected using the following selection criteria: conception later than 42 DIM, calving season July to September, no records of veterinary treatment and the level of energy fed as concentrates between 8.69 and 12.83 MJ. The shape of the lactation curves were parameterized using a modified Wilmink-model in a mixed model analysis. Differences in the parameters of the lactation curves with different conception times were evaluated using confidence intervals.

Results

Lactation curves characterized by a low intercept and a steep ascending slope and a steep descending slope were associated with early conception across all parities. The peak milk yield was not associated with time of conception.

Conclusions

A practical application of the study results is the use of the shape of the lactation curve in future herd management. Groups of cows with impaired reproductive performance may be identified due to an unfavorable shape of the lactation curve. Monitoring lactation curves and adjusting the feeding strategy to adjust yield therefore may be useful for the improvement of reproductive performance at herd level.  相似文献   

A meta-analysis comparing the effect of PCV2 vaccines on average daily weight gain and mortality rate in pigs from weaning to slaughter     

Kristensen CS  Baadsgaard NP  Toft N 《Preventive veterinary medicine》2011,98(4):3206-258

The aim of this investigation was, through a meta-analysis, to review the published literature concerning the effect of PCV2 vaccination on the average daily weight gain (ADG) and on the mortality rate in pigs from weaning to slaughter. The review was restricted to studies investigating the effect of vaccines against PCV2 published from 2006 to 2008, identified using computerised literature databases. Only studies that met the following criteria were included: commercial vaccines were used, pigs or pens were assigned randomly to vaccination versus control groups in herds naturally infected with PCV2, and vaccinated and non-vaccinated pigs were housed together. Furthermore, it was a requirement that sample size, age at vaccination, and production period were stated. The levels of ADG and mortality rate had to be comparable to those seen in modern intensive swine production. In total, 107 studies were identified; 70 were excluded because they did not fulfil the inclusion criteria and 13 were identical to results published elsewhere. A significant effect of PCV2 vaccination on ADG was found for pigs in all production phases. The largest increase in ADG was found for finishing pigs (41.5g) and nursery-finishing pigs (33.6g) with only 10.6g increase in the nursery pigs. Mortality rate was significantly reduced for finishing pigs (4.4%) and nursery-finishing pigs (5.4%), but not for nursery pigs (0.25%). Herds negative for PRRS had a significantly larger increase in ADG compared to herds positive for PRRS. The PRRS status had no effect on mortality rate.  相似文献   

Intra- and inter-observer agreement when using a descriptive classification scale for clinical assessment of faecal consistency in growing pigs     

Pedersen KS  Toft N 《Preventive veterinary medicine》2011,98(4):284-291

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Sensitivity of <Emphasis Type="Italic">Eisenia fetida</Emphasis> in comparison to <Emphasis Type="Italic">Aporrectodea caliginosa</Emphasis> and <Emphasis Type="Italic">Lumbricus terrestris</Emphasis> after imidacloprid exposure. Body mass change and histopathology     

Nils Dittbrenner  Hannah Schmitt  Yvan Capowiez  Rita Triebskorn 《Journal of Soils and Sediments》2011,11(6):1000-1010

Purpose  

The use of only one or a few species—representing an entire taxon—in ecotoxicological standard tests poses risk of underestimating the impact of toxicants on the environment. In earthworm ecotoxicity tests, the species Eisenia fetida or Eisenia andrei are commonly used, and there is evidence that these species respond relatively insensitive towards environmental pollution. With the present study, we wanted to evaluate the risk of underestimating effects of the insecticide imidacloprid in soil organisms by comparing E. fetida with two other earthworm species (Aporrectodea caliginosa and Lumbricus terrestris) regarding their sensitivities towards soil contaminated with this widely used insecticide.  相似文献   

Inert agricultural spray adjuvants may increase the adverse effects of selected insecticides on honey bees (Apis mellifera L.) under laboratory conditions     

Wernecke  Anna  Eckert  Jakob H.  Forster  Rolf  Kurlemann  Nils  Odemer  Richard 《植物病害和植物保护杂志》2022,129(1):93-105

Journal of Plant Diseases and Protection - Currently, more than 360 spray adjuvants are registered in Germany (September 2021). Unlike plant protection products (PPPs), adjuvants are not subjected...  相似文献   

Hydrology influences breeding time in the white-throated dipper     

Nilsson  Anna L. K.  Skaugen  Thomas  Reitan  Trond  L’Abée-Lund  Jan Henning  Gamelon  Marlène  Jerstad  Kurt  Røstad  Ole Wiggo  Slagsvold  Tore  Stenseth  Nils C.  Vøllestad  L. Asbjørn  Walseng  Bjørn 《BMC ecology》2020,20(1):1-12

While nitrogen and carbon stable isotope values can reflect ecological segregation, prey choice and spatial distribution in seabirds, the interpretation of bulk stable isotope values is frequently hampered by a lack of isotopic baseline data. In this study, we used compound-specific isotope analyses of amino acids (CSIA-AA) to overcome this constraint and to study interspecific differences, seasonal and historical changes in trophic positions of five seabird species, three penguins and two petrels, from a sub-Antarctic seabird community. CSIA-AA allowed comparing trophic positions of seabirds with temperate and polar distributions. Gentoo and Magellanic penguins had the highest trophic positions during the breeding season (3.7 and 3.9), but decreased these (2.9 and 3.3) during the feed-up for moult. Intra-specific differences were also detected in Thin-billed prions, where carbon isotope values clearly separated individuals with polar and temperate distributions, both in the breeding and interbreeding periods. Thin-billed prions that foraged in polar waters had lower trophic positions (3.2) than conspecifics foraging in temperate waters (3.8). We further investigated historical changes by comparing museum samples with samples collected recently. Our pilot study suggests that Rockhopper penguins, Magellanic penguins and Thin-billed prions with temperate non-breeding distributions had retained their trophic levels over a 90–100 year period, while Gentoo penguins and Thin-billed prions with polar non-breeding distributions had decreased trophic levels compared to historical samples. In contrast, Wilson’s storm-petrels had slightly increased trophic levels compared to samples taken in 1924–1930. We applied compound-specific stable isotope analyses across a range of contexts, from intra-specific comparisons between stages of the breeding cycle to inter-specific seabird community analysis that would not have been possible using bulk stable isotope analyses alone due to differences in isotopic baselines.  相似文献   

Effects of a Brief Elevation of Scrotal Temperature on the Post-thaw Viability of Bull Semen     

A Januskauskas  J Gil  H Rodriguez-Martínez  L Söderquist  N Lundeheim 《Reproduction in domestic animals》1995,30(5):271-277

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