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171.
Response time of broiler chickens to cimaterol: meat tenderness, muscle composition fiber size, and carcass characteristics. 总被引:4,自引:0,他引:4
The response time to cimaterol (CIM), a beta-adrenergic agonist, by broiler chickens for carcass characteristics, muscle composition, muscle fiber size, catheptic enzyme activity, and tenderness was determined. Two trials were conducted in which chickens were fed a control diet (CON) containing 0 ppm of CIM or a diet containing 1 ppm of CIM. Trial 1 consisted of 55, 31-d-old broiler chickens individually fed for up to 48 h. At 0, 6, 12, 18, 24, and 48 h, five CON and five CIM-fed chickens were killed. Trial 2 consisted of 160, 33-d-old broiler chickens group-fed for up to 14 d. At 2, 4, 6, 8, 10, 12, and 14 d, 10 CON and 10 CIM-fed chickens were killed. The breast muscle (BM) and leg muscle (LM) weight, cathepsin B and L activities, DNA, RNA, and protein concentration, and BM shear force value (SFV) were measured in both trials. Thigh muscle (TM) SFV were measured in Trial 2 only. Fiber size of BM was measured (five birds per treatment) at d 2, 6, 10, and 14. In Trial 1, BM weight and SFV were lower in CIM-fed birds at 6 h (P less than .05). In Trial 2 BM SFV were higher at d 8 (P = .06) and d 10 (P less than .05) in CIM-fed chickens. The SFV of CIM-fed chickens were higher at d 4, 8, 10, 12, and 14 (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
172.
In a nine-year-old female cat, the diagnostic procedure, therapy and differential diagnoses of a rare, primary, malignant, epibulbar melanoma are presented. Post-operatively no recidivation or metastases occurred within 18 months. 相似文献
173.
With the help of a new synthetic material follicles and corpora lutea from the ovaries of 80 cows in different stages of the sexual cycle were examined for modifications of their blood vessel architecture. In the theca externa the main artery which runs towards the follicle, separates into arterioles of which capillaries derive in the theca interna, building a basket-like network around the zona granulosa. After ovulation the follicle wall forms characteristic fields. Capillaries grow into the zona granulosa and thus the folds form the lobular structure of the corpus luteum. Capillaries which rise from the ruptured part of the follicle, spread centripetally and together with lutein cells they build up the not lobulated cupola of the corpus luteum. The regression of the corpus luteum starts around the 16th day of the cycle, beginning at the capillary network of the cupola. A contraction of the vessels and a quick decrease of the volume follow. 相似文献
174.
Abstract. Recent developments in in situγ ray spectrometry offer a new approach to measuring the activity of radionuclides such as 137Cs and 40K in soils, and thus estimating erosion or deposition rates and field moist bulk density (ρm). Such estimates would be rapid and involve minimal site disturbance, especially important where archaeological remains are present. This paper presents the results of a pilot investigation of an eroded field in Scotland in which a portable hyper pure germanium (HPGe) detector was used to measure γ ray spectra in situ. The gamma (γ) photon flux observed at the soil surface is a function of the 137Cs inventory, its depth distribution characteristics and ρm. A coefficient, QCs, derived from the forward scattering of 137Cs γ ray photons within the soil profile relative to the 137Cs full energy peak (662 keV), was used to correct the in situ calibration for changes in the 137Cs vertical distribution in the ploughed field, a function of tillage, soil accumulation and ρm. Based on only 8 measurements, the agreement between in situγ ray spectrometry and soil sample measurements of 137Cs inventories improved from a non significant r2=0.05 to a significant r2=0.62 (P<0.05). Erosion and deposition rates calculated from the corrected in situ137Cs measurements had a similarly good agreement with those calculated from soil cores. Mean soil bulk density was also calculated using a separate coefficient, QK, derived from the forward scattering γ photons from 40K within the soil relative to the 40K full energy peak (1460 keV). Again there was good agreement with soil core measurements (r2=0.64; P<0.05). The precision of the in situ137Cs measurement was limited by the precision with which QCs can be estimated, a function of the low 137Cs deposition levels associated with the weapons testing fallout and relatively low detector efficiency (35%). In contrast, the precision of the in situ ρm determination was only limited by the spatial variability associated with soil sampling. 相似文献
175.
H Ano S Makimura R Harasawa 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(5):561-562
Nucleotide sequences of ribosomal DNA (rDNA) of Babesia (B.) gibsoni occurring in Miyazaki, western Japan, were examined using blood samples obtained from seven dogs suffering from natural canine babesiosis. DNA isolated from these blood samples was subjected to the polymerase chain reaction (PCR). The nucleotide sequences of the PCR products were determined and compared with other rDNA sequences of B. gibsoni isolated from Asia, Europe and U.S.A. Although homology values between our isolates and those isolated from Europe and U.S.A. were both 84.0%, respectively, our isolates were identical to the Asian types. In conclusion, B. gibsoni occurring in Miyazaki was revealed to have the genotype Asia 1 or Asia 2 from a comparison of the partial rDNA sequences. 相似文献
176.
D A Ward K S Latimer R M Askren 《Journal of the American Veterinary Medical Association》1992,200(10):1503-1506
Squamous cell carcinoma is an uncommon tumor of the cornea in dogs. A 12-year-old Shih Tzu with a history of chronic keratoconjunctivitis sicca was diagnosed as having squamous cell carcinoma of the corneoscleral limbus. The lesion was treated by surgical resection and cryotherapy. One year after surgery, multiple tumors, apparently unrelated to the first tumor, appeared on the same cornea. Keratoconjunctivitis sicca may have predisposed the dog to corneal squamous cell carcinoma development. 相似文献
177.
Persistence and mobility of chlorsulfuron and metsulfuron under different soil and climatic conditions 总被引:3,自引:0,他引:3
The persistence and mobility of chlorsulfuron and metsulfuron were studied in Italy at four field locations. Chlorsulfuron was applied pre-emer-gence to wheat at 15 and 30 g a.i. ha?1 in the autumn of 1986 and metsulfuron early post-emergence at 8 g a.i. ha?1 in the spring of 1987. Soil samples were taken periodically at each location for 1 year. Trials were conducted until 1989 at three locations. After the wheat harvest in 1989, chlorsulfuron and metsulfuron residues in the soil were measured by bioassay in plots that had been treated annually for 3 years and also in plots that had received single treatments. Chlorsulfuron at both application rates dissipated to levels below 0.3 g a.i. ha?1 over 12 months at three locations while, at the fourth, which received only 250 mm rain during the study, significant levels of residues were still present after 15 months. The degradation of chlorsulfuron applied at 30 g a.i. ha?1 followed first-order kinetics, with half-lives of 149, 70, 59 and 51 days at the four locations. Chlorsulfuron mobility was high at three locations while, in the silty clay soil of the fourth, the herbicide was confined to the upper 30 cm, despite the high rainfall. Metsulfuron applied in spring was detected only in the first soil sample collection. It was present in all sampled layers at one location but, in the others, was confined to the surface layer. There was no evidence of herbicide accumulation in the soil with repeated applications. Persistance et mobilité du chlorsulfuron et du met-sulfuron dans différents sols et sous différentes conditions climatiques La persistance et la mobilité du chorsulfuron et du metsulfuron au champ ont étéétudiées en Italie sur quatre sites. Le chlorsulfuron était appliqué en pré-levée sur le blé aux doses de matière active (m.a.) 15 et 30 g ha?1à l'automne 1986 et le metsulfuron en post-levée précoce à la dose 8 g m.a. ha?1 au printemps 1987. Des échantillons de sol étaient prélevés périodiquement sur chaque site pendant 1 an. Les essais ont été conduits jusqu'en 1989 sur trois des sites. En 1989, après la récolte du blé. les résidus de chlorsulfuron et de metsulfuron dans le sol ont été mesurés par des essais biologiques dans des parcelles qui avaient été traitées chaque année pendant 3 ans, ainsi que dans des parcelles qui n'avaient reçu qu'un seul traitement. Le chlorsulfuron aux deux doses disparaissait jusqu'à des niveaux inférieurs à 0.3 g m.a. ha?1 en 12 mois sur trois des sites, alors que sur le quatrième, qui n'a reçu que 250 mm de précipitations pendant l'étude, des résidus étaient présents en quantité significative après 15 mois. La dégradation du chlorsulfuron appliquéà la dose 30 g m.a. ha?1 suivait une cinétique du premier ordre, avec des demi-vies 149, 70, 59 et 51 j sur les quatre sites. La mobilité du chlorsulfuron était élevée sur trois des sites alors que sur le quatrième oú le sol était une argile limoneuse, l'herbicide était confiné aux 30 cm superficiels en dépit de précipitations élevées. Le metsulfuron appliqué au printemps n'était détecté que dans le premier prélèvement. Sur un des sites, il était présent dans toutes les couches, mais était confinéà la couche superficielle sur les autres sites. Après des applications répétées, aucune accumulation d'herbicide n'était observée dans le sol. Persistenz und Mobilität von Chlorsulfuron und Metsulfuron in verschiedenen Böden und bei unterschiedlicher Witterung Die Persistenz und Mobilität von Chlorsulfuron und Metsulfuron wurden in Italien an 4 Standorten unter Freilandbedingungen untersucht. Chlorsulfuron wurde im Herbst 1986 bei Weizen im Vorauflauf mit 15 und 30 g AS ha?1 und Metsulfuron im Frühjahr 1987 im frühen Nachauflauf mit 8 g AS ha?1 angewandt. Von jeder Versuchsfläche wurden über einen Zeitraum von 1 Jahr periodisch Bodenproben entnommen. Die Versuche wurden an 3 Standorten bis 1989 durchgeführt. Nach der Weizenernte 1989 wurden mit Biotests die Rückstände von Chlorsulfuron und Metsulfuron in den Böden mit jährlicher (über 3 Jahre) sowie mit einmaliger Behandlung bestimmt. Die Chlorsulfuron-Rückstände nahmen an 3 Standorten bei beiden Aufwandmengen nach 12 Monaten auf 0,3 g AS ha?1 ab. Am 4. Standort, wo während der Untersuchung nur 250 mm Niederschlag gefallen waren, wurden nach 15 Monaten noch signifikante Rückstände gefunden. Der Abbau von Chlorsulfuron folgte an allen Standorten bei einer Aufwandmenge von 30 g AS ha?1 einer Kinetik erster Ordnung mit Halbwertszeiten von 149, 70, 59 und 51 Tagen. Die Mobilität von Chlorsulfuron war an 3 Standorten hoch, während es in dem schluffigen Tonboden des 4. Standortes trotz hohen Niederschlags in den oberen 30 cm verblieb. Das im Frühjahr ausgebrachte Metsulfuron wurde nur in der 1. Bodenprobenserie gefunden. An einem Standort lagen in allen beprobten Bodenschichten Rückstände vor, doch sonst waren sie auf die oberste Bodenschicht beschränkt. Bei wiederholter Anwendung konnte keine Herbizidakkumulation im Boden festgestellt werden. 相似文献
178.
179.
Martin W. Brunson Richard W. Taylor Bert J. Hoff 《Journal of the World Aquaculture Society》1988,19(1):8-13
Twenty-five domestic rice (Oryza sativa L.) cultivars were evaluated in a simulated rice/crawfish double cropping system in southwest Louisiana during 1983 and 1984. Wide variation was observed among cultivars in parameters believed to be important for maximizing productivity in such a system. Mean maturity ranged from 99 (Labelle) to 118 days (Starbonnet), while height ranged from 76 (Bellemont) to 130 cm (Della, Nato). Significant differences in grain yield response were observed, with yields ranging from 4,101 (Bluebelle) to 6,665 kg/hectare (Newbonnet). Straw dry matter production varied greatly, from 3,831 (Bellemont) to 9,170 kg/hectare (Della), and was positively correlated with plant height (r = 0.64; P = 0.0001). Ratoon biomass production was negatively correlated with both grain yield (r = -0.39; P = 0.0001) and maturity group (r = -0.69; P = 0.0001). Plant senescence at grain maturity also varied greatly and appears to be a factor in post-harvest ratoon capability. Early or very early maturing cultivars with both proven grain production and good ratooning capability appear best suited. Cultivar selection should be based upon individual farm situations and currently employed agronomic practices. 相似文献
180.
The dietary lysine requirement of juvenile red drum Sciaenops ocellatus was reevaluated in two separate experiments. In the first experiment, lyophilized red drum muscle was combined with an L-form crystalline amino acid premix to yield diets containing approximately 35% protein on a dry-matter basis. Gradations (0.25%) of L-lysine HCl were added to the basal diet containing approximately 1.0% lysine. Each diet was fed to triplicate groups of juvenile red drum initially weighing 6–7 g for 8 weeks. Based on growth and feed efficiency data, the lysine requirement (±SE) was determined to be 1.55% (±0.079%) of dry diet or 4.430% of dietary protein. In a second experiment, the lysine requirement of red drum was investigated with diets containing 35% intact protein from zein and red drum muscle. Each of the zein-based diets containing incremental levels of lysine was fed to triplicate groups of juvenile red drum initially weighing 1–2 g for 8 weeks. A crystalline amino acid test diet serving as a control in this experiment significantly outperformed the zein-based diets, and palatability of those diets was questionable due to an obvious change in feeding behavior of the fish. Due to the inferior performance of the fish fed the zein-based diets, the authors were not successful in determining a requirement with these diets. Thus, a lysine requirement of 1.55% of dry diet (4.43% of dietary protein) as determined in the first experiment is recommended for juvenile red drum. 相似文献