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Langer E 《Science (New York, N.Y.)》1966,153(3735):508-512
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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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Artemisia pallens Bess. is a low volume and high value essential oil plant used in perfumery, cosmetic and flavouring industries. On account
of the failure of conventional procedures to induce variability in species, mutation techniques have been tried in our experiments.
Dry and viable seeds (moisture content 8%) of homozygous pure breeding lines were subjected to 150–500 Gy doses of gamma rays
and 0.01–0.1% ethyl methane sulphonate (EMS) for 8 h. Desirable qualitative mutants were recovered from segregating M2 generation (4,283 plants scored) raised as single plant progenies. The spectrum of morphological mutants included late and
early flowering types; bushy and high yielding types; tall and more capitula-producing types and high oil and high davanone
yielding types. These were raised through M3 families to evaluate stability and transmission of mutant characters. As such out of 15 different types selected in M2, only 11 types bred true to their characteristic variability. Based on their performance, the mutants were characterised
depending upon their distinguishing features. Davanone, the main component of oil showed the maximum increase (64.22% against
54.64% in control) in mutant ‘S–5’ recovered from exposure with 250 Gy γ-rays. Mutant ‘E-6’ was economically most viable having
increased oil biosynthesis (0.36% against 0.22% in control) and hence yields higher oil per unit area than the parental control
(isolated from 0.05% EMS treatment). 相似文献
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Enzymatic removal of bilirubin from blood: a potential treatment for neonatal jaundice 总被引:2,自引:0,他引:2
Current treatments for severe jaundice can result in major complications. Neonatal jaundice is caused by excessive accumulation of bilirubin in the blood. A small blood filter containing immobilized bilirubin oxidase was developed to reduce serum bilirubin concentrations. When human or rat blood was passed through the enzyme filter, more than 90 percent of the bilirubin was degraded in a single pass. This procedure may have important applications in the clinical treatment of neonatal jaundice. 相似文献