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1.
Kaarina Matilainen Ismo Strandén Gert Pedersen Aamand Esa A. Mäntysaari 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(5):337-348
Joint Nordic (Denmark, Finland, Sweden) genetic evaluation of female fertility is currently based on the multiple trait multilactation animal model (BLUP). Here, single step genomic model (ssGBLUP) was applied for the Nordic Red dairy cattle fertility evaluation. The 11 traits comprised of nonreturn rate and days from first to last insemination in heifers and first three parities, and days from calving to first insemination in the first three parities. Traits had low heritabilities (0.015–0.04), but moderately high genetic correlations between the parities (0.60–0.88). Phenotypic data included 4,226,715 animals with records and pedigree 5,445,392 animals. Unknown parents were assigned into 332 phantom parent groups (PPG). In mixed model equations animals were associated with PPG effects through the pedigree or both the pedigree and genomic information. Genotype information of 46,914 SNPs was available for 33,969 animals in the pedigree. When PPG used pedigree information only, BLUP converged after 2,420 iterations whereas the ssGBLUP evaluation needed over ten thousand iterations. When the PPG effects were solved accounting both the pedigree and the genomic information, the ssGBLUP model converged after 2,406 iterations. Also, with the latter model breeding values by ssGBLUP and BLUP became more consistent and genetic trends followed each other well. Models were validated using forward prediction of the young bulls. Reliabilities and variance inflation of predicted genomic breeding values (values for parent averages in brackets) for the 11 traits ranged 0.22–0.31 (0.10–0.27) and 0.81–0.95 (0.83–1.06), respectively. The ssGBLUP model gave always higher validation reliabilities than BLUP, but largest increases were for the cow fertility traits. 相似文献
2.
Movement patterns of seaward migrating European eel (Anguilla anguilla) at a complex of riverine barriers: implications for conservation
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Adam T. Piper Jon C. Svendsen Rosalind M. Wright Paul S. Kemp 《Ecology of Freshwater Fish》2017,26(1):87-98
River infrastructure such as weirs and hydropower stations commonly present migrating fish with multiple potential passage routes. Knowledge of the cues fish use to navigate such environments is required to protect migrants from hazardous areas and guide them towards safe passage; however, this is currently lacking for many species. Employing high‐resolution positioning telemetry, this study examined movements of downstream migrating adult European eel, Anguilla anguilla, as they encountered a complex of water control structures in one location on the River Stour, southern England. The distribution of eels across five potential routes of passage differed from that predicted based on proportion of discharge alone. Certain routes were consistently avoided, even when the majority of flow passed through them. Passage distribution was partially explained by avoidance in the vicinity of a floating debris boom. Movement paths were nonrandomly distributed across the forebay and eels moved predominantly within a zone 2–4 m from the channel walls. Understanding of avoidance and structure oriented movementation exhibited by eels will help advance effective guidance and downstream passage solutions for adults. 相似文献
3.
Of the many client groups with interests in irrigation system performance, farmers are probably the least often considered. This paper attempts to explore the meaning of irrigation performance from their perspective, highlighting at the outset basic difference between this perspective and that of system managers. It then reviews several important concepts underlying a consideration of performance in irrigation systems. The paper then proposes and discusses a set of twelve measures of irrigation service judged to be of interest to farmers. These are adequacy, timeliness, equity, tractability, convenience, predictability, temperature, sediment content, salt content, nutrient content, toxics, and pathogens. 相似文献
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The Turkish program of irrigationmanagement transfer has gained worldwidecelebrity for its speed and effectiveness. This paper describes the program brieflyand assesses its effectiveness from anational perspective. The assessmentincludes changes in staffing levels,operational costs, service fee levels, andcost recovery from farmers. A companionpaper examines impacts at the local leveland looks specifically at changes in systemperformance. 相似文献
6.
Fourteen oxime ethers and eleven other unsaturated compounds derived from 2,2-dimethyl-3-(3-phenoxybenzyloxy)propanal were synthesised and their insecticidal activity against Musca domestica, Locusta migratoria, Dysdercus cingulatus, Aedes aegypti, Plutella xylostella, Drosophila melanogaster, Tetranychus urticae and Spodoptera littoralis tested. Structural variations including chain length, branching and unsaturation of the oxime ether O-alkyl group and substituent exchange at the carbon-carbon double bond of the unsaturated compounds were made in order to examine the structure-activity relationship. All biological activities were compared with the activity of the ether pyrethroid MTI-500. 相似文献
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Enteric Escherichia coli diseases in weaned pigs 总被引:2,自引:0,他引:2
J Svendsen 《Nordisk veterinaermedicin》1974,26(3):226-238
9.
Preweaning mortality in pigs. 2. The perinatal period 总被引:3,自引:0,他引:3
10.
McNicholas WT Wilkens BE Blevins WE Snyder PW McCabe GP Applewhite AA Laverty PH Breur GJ 《Journal of the American Veterinary Medical Association》2002,221(12):1731-1736
OBJECTIVE: To determine clinical, radiographic, and histologic abnormalities in adult cats > 1 year old with spontaneous (ie, nontraumatic) femoral capital physeal fractures. DESIGN: Retrospective study. ANIMALS: 26 cats. PROCEDURE: Medical records of cats > 1 year old with femoral capital physeal fractures and no history of trauma were examined. RESULTS: Mean +/- SD age of the cats was 22.5 +/- 6.5 months. Twenty-five cats were neutered males. Mean weight of the cats was significantly greater than mean weight of a group of age- and sex-matched control cats. Of 16 cats for which age at the time of neutering was known, 14 had been neutered before 6 months of age. Nine cats had bilateral fractures. Severity of femoral neck osteolysis and sclerosis increased with increased duration of clinical signs. The contralateral femoral capital physis, distal femoral physes, and proximal tibial physes were radiographically open in 13 of 18,19 of 24, and 24 of 24 cats, respectively. Histologically, the epiphysis contained normal articular cartilage and bone, but attached growth plate cartilage lacked the normal columnar arrangement of chondrocytes. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that adult cats with spontaneous femoral capital physeal fractures were most likely to be heavier, neutered males with delayed physeal closure. 相似文献