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R Kasimanickam S Schroeder M Assay V Kasimanickam DA Moore JM Gay WD Whittier 《Reproduction in domestic animals》2014,49(5):775-782
The objectives were (i) to evaluate the effect of temperament, determined by modified 2‐point chute exit and gait score, on artificial insemination (AI) pregnancy rates in beef heifers following fixed time AI and (ii) to determine the effect of temperament on cortisol, substance‐P, prolactin and progesterone at initiation of synchronization and at the time of AI. Angus beef heifers (n = 967) at eight locations were included in this study. At the initiation of synchronization (Day 0 = initiation of synchronization), all heifers received a body condition score (BCS), and temperament score (0 = calm; slow exit and walk or 1 = excitable; fast exit or jump or trot or run). Blood samples were collected from a sub‐population of heifers (n = 86) at both synchronization initiation and the time of AI to determine the differences in serum progesterone, cortisol, prolactin and substance‐P concentrations between temperament groups. Heifers were synchronized with 5‐day CO‐Synch+ controlled internal drug release (CIDR) protocol and were inseminated at 56 h after CIDR removal. Heifers were examined for pregnancy by ultrasound 70 days after AI to determine AI pregnancy. Controlling for synchronization treatment (p = 0.03), facility design (p = 0.05), and cattle handling facility design by temperament score interaction (p = 0.02), the AI pregnancy differed between heifers with excitable and calm temperament (51.9% vs 60.3%; p = 0.01). The alley‐way with acute bends and turns, and long straight alley‐way had lower AI pregnancy rate than did the semicircular alley‐way (53.5%, 56.3% and 67.0% respectively; p = 0.05). The serum hormone concentrations differed significantly between different types of cattle handling facility (p < 0.05). The cattle handling facility design by temperament group interactions significantly influenced progesterone (p = 0.01), cortisol (p = 0.01), prolactin (p = 0.02) and substance‐P (p = 0.04) both at the initiation of synchronization and at the time of AI. Inter‐ and intra‐rater agreement for temperament scoring were moderate and good (Kappa = 0.596 ± 0.07 and 0.797 ± 0.11) respectively. The predictive value for calm and pregnant to AI was 0.87, and excited and non‐pregnant to AI was 0.76. In conclusion, the modified 2‐point temperament scoring method can be used to identify heifers with excitable temperament. Heifers with excitable temperament had lower AI pregnancy. Further, cattle handling facility design influenced the temperament and AI pregnancy. 相似文献
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Accretion of primitive planetesimals: Hf-W isotopic evidence from enstatite chondrites 总被引:1,自引:0,他引:1
Enstatite chondrites have often been considered to be closely related to the material from which Earth accreted. However, tungsten isotopic data reveal clear differences. Moreover, the silicate and metal fractions define distinct initial (182)Hf/(180)Hf corresponding to a 13.8 +/- 5.3 million year apparent age difference. Internal reequilibration does not provide a ready explanation for this result. Larger scale redistribution of tungsten is more likely, such as may have occurred during collisions between planetesimals. 相似文献
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The use of hafnium-tungsten chronometry to date the Moon is hampered by cosmogenic tungsten-182 production mainly by neutron capture of tantalum-181 at the lunar surface. We report tungsten isotope data for lunar metals, which contain no 181Ta-derived cosmogenic 182W. The data reveal differences in indigenous 182W/184W of lunar mantle reservoirs, indicating crystallization of the lunar magma ocean 4.527 +/- 0.010 billion years ago. This age is consistent with the giant impact hypothesis and defines the completion of the major stage of Earth's accretion. 相似文献
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Hf-W Isotopic Evidence for Rapid Accretion and Differentiation in the Early Solar System 总被引:1,自引:0,他引:1
The time scales over which inner solar system objects accreted and differentiated are unclear because the isotopic systems of many meteorites are disturbed. 182Hf decays to 182W with a half-life of 9 million years and is a particularly useful chronometer because both elements are highly refractory and immobile. Tungsten isotopic data for IIA, IIIA, IVA, and anomalous iron meteorites and H, L, and LL chondrites indicate that their parent bodies accreted rapidly and segregated metal within just a few million years. 相似文献
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The effects of selenium, housing and management on the incidence of pneumonia in housed calves 总被引:2,自引:0,他引:2
The occurrence and incidence of pneumonia in housed calves were not related to the selenium status of the herd as measured by blood glutathione peroxidase activity nor were they affected by selenium treatment of calves during the neonatal period. Pneumonia was related more closely to herd size and building design. 相似文献
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1. Groups of 30 broilers from seven flocks were bled and weighed at the farm and a further sample of 10 broilers from each flock was transported from 8 to 16 km to the laboratory prior to bleeding and weighing. 2. One haematological and 11 biochemical analyses were made on each blood sample. 3. Although transportation did lead to significant differences in certain variables, the trends were consistent and sampling following transit is considered acceptable for clinical pathology studies. 相似文献
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CASE HISTORY: A mature male tuatara was presented with a history of recurrent cloacal prolapse. CLINICAL AND PATHOLOGICAL FINDINGS: The prolapsed tissue included a 12 mm diameter mass, which histologically showed cords and nodules of neoplastic epithelial cells. DIAGNOSIS: The mass was diagnosed as a squamous cell carcinoma with ulceration of the overlying stratified squamous epithelium and diffuse inflammation of the surrounding dermis. CLINICAL RELEVANCE: This case presented a rare opportunity to investigate squamous cell carcinoma in a long-lived lower vertebrate species. Future recurrence or metastasis of the mass may add useful information to the current base of knowledge of the behaviour of malignant neoplasms in reptiles. 相似文献