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Frdrick G. Sunstrum Wubishet A. Bekele Charlene P. Wight Weikai Yan Yuanhong Chen Nicholas A. Tinker 《Plant Breeding》2019,138(1):82-94
We developed 178 recombinant inbred lines from a southern‐by‐spring oat population designated as “TxH.” These lines were genotyped to generate a high‐quality linkage map that resolved 6,902 markers into 21 linkage groups that matched closely with the latest hexaploid oat consensus map. Three major quantitative trait loci (QTLs) affecting heading date were found in locations that are consistent with known QTLs and candidate genes, and two other QTLs affecting heading date were found in novel locations. Five QTLs affecting plant height were found. Both sets of QTLs are responsible for transgressive segregation observed for these two traits. Four QTLs affecting resistance to crown rust, caused by the pathogen Puccinia coronata f. sp. avenae, were identified. Two of these QTLs are consistent with known clusters of rust resistance genes, while two may represent new locations of novel rust resistance genes. A complete set of SNP sequences suitable for generating markers for molecular selection is provided. 相似文献
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Sedative and cardiovascular effects of romifidine, alone and in combination with butorphanol, in the horse 总被引:1,自引:1,他引:0
The behavioural and sedative effects of intravenous (iv) romifidine (40 and 80 μg/kg bodyweight [bwt]) alone or in combination with iv butorphanol (50 μg/kg bwt) were investigated in four ponies and one Thoroughbred horse. Apparent sedation, as judged by the lowering of the head, and by the response to imposed touch, visual and sound stimuli was assessed. The combination with butorphanol reduced the animals' response to imposed stimuli when compared with the effect of the same dose of romifidine alone. Following the administration of romifidine/butorphanol combinations muzzle tremor was noted and some animals attempted to walk forward. In a separate series, the cardiopulmonary effects of iv romifidine (80 μg/kg bwt) alone, or in combination with butorphanol (50 μg/kg bwt) were investigated. Romifidine and the romifidine/butorphanol combination caused similar cardiovascular changes, these being bradycardia with heart block, and hypertension followed by hypotension. Romifidine caused a transient decrease in arterial oxygen tensions and arterial carbon dioxide tensions had increased significantly by the end of the 90 min recording period. Romifidine/butorphanol combinations produced significantly higher arterial carbon dioxide tensions during the first 15 mins after drug administration than did romifidine alone. Butorphanol at 50 μg/kg bwt iv reduced the response to imposed stimuli in horses sedated with romifidine. The combination produced no cardiovascular changes beyond those induced by romifidine alone, but did increase the degree of respiratory depression. 相似文献
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Abstract Sir, - Andrews'((2)) checklist of helminth parasites of wild ruminants in New Zealand recorded the presence of 10 species of gastrointestinal nematodes in chamois (Rupicapra rupicapra rupicapra L.) from "Central South Island". In October 1978 we examined 28 freshly-shot chamois cadavers from the Harper-Avoca watershed in the headwaters of the Rakaia River. Six of the nematode species reported by Andrews were found again; viz. Ostertagia ostertagi, O. circumcincta, O. trifurcata, Nematodirus filicollis, Oesophagostomum venulosum and Trichuris ovis. The 4 species found by Andrews that were not recovered by us from the animals we examined were: Trichostrongylus axei, T. vitrinus, Spiculotragia spiculoptera and S. asymmetrica. On the other hand we found 4 helminths not encountered by Andrews: 3 nematodes: Nematodirus spathiger (Railliet, 1896), N. abnormalis (May, 1920), and Chabertia ovina (Fabricius, 1794), and 7 specimens of the cestode Moniezia expansa (Rud., 1805). Nematodirus spathiger was the most commonly encountered Nematodirus species, but generally the numbers of all 3 species encountered were low as might be expected in a sample of adult and almost year-old animals. It is probable that most of the adults had acquired some measure of immunity((3)), and the most susceptible group, the kids, would not be born until late November. Because peptic digestion was not used to recover juveniles from the intestinal submucosa, only small numbers of adults were obtained. 相似文献