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301.
R O Myer D D Johnson D A Knauft D W Gorbet J H Brendemuhl W R Walker 《Journal of animal science》1992,70(12):3734-3741
A high-oleic-acid peanut breeding line was used in a study designed to determine the effects of feeding swine diets containing elevated levels of monounsaturated fatty acids as a means to increase the level of monounsaturates and total unsaturates in the resulting carcass fat. Forty-eight pigs were allotted to four treatments that consisted of corn-soybean meal diets that contained 1) high-oleic peanuts (HOP), 2) regular commercial peanuts (RP), or 3) canola oil (CO), each added at a dietary level to provide 10% added fat/oil, and 4) a control diet with no added fat/oil. The oil of HOP averaged 75% oleic acid vs 60% for CO and 53% for RP. The pigs were fed the experimental diets from 33 to 102 kg BW, after which all pigs were slaughtered. All three dietary oil sources resulted in increases (P < .01) of monounsaturates in the backfat; the HOP diet resulted in the greatest increase (32% greater than control). Both CO and RP increased (P < .01) the level of polyunsaturates by nearly twofold; HOP resulted in a small decrease. Total unsaturates increased (P < .01) by 24, 24, and 27% for HOP, RP, and CO treatments, respectively, over that obtained from the control treatment. Carcass fat was softer/oilier (P < .05) from pigs fed CO and RP diets, but not from those fed HOP diets, compared with carcass fat of pigs fed the control diet. Dietary fat/oil source had no effect (P > .05) on other carcass compositional traits and various meat quality attributes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
302.
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
303.
304.
MICHAEL A. PRICHARD DVM RICHARD P. HACKETT DVM MS Diplomate ACVS HOLLIS N. ERB DVM PhD 《Veterinary surgery : VS》1992,21(2):145-149
The records of 61 horses undergoing tooth repulsion for treatment of alveolar periostitis were reviewed. Seventeen of 36 horses (47%) in which maxillary teeth were removed had serious postoperative complications, such as infection of a second tooth, bone sequestration, chronic sinusitis, draining tracts, retained dental packing, feed impaction of the alveolus or sinus, suture-line dehiscence, or skin-flap sloughs. Eight horses required at least one additional surgical procedure. Eight of 25 horses (32%) in which mandibular teeth were removed had serious postoperative complications, and four horses required an additional surgical procedure. Hospitalization lasted 2 to 61 days (median, 22 days) for maxillary teeth and 3 to 35 days (median, 8 days) for mandibular teeth. Long-term follow-up (at least 5 months) was possible in 47 horses. Twenty-four of 30 horses (80%) with maxillary tooth repulsion healed without further problems; six horses had persistent nasal discharge. Fourteen of 17 horses (82%) with mandibular tooth repulsion healed with no further problems or with only minor complications; three horses had a chronic draining tract. 相似文献
305.
The possible relationship between nutrition and fertility in dairy cows are reviewed. Study of the literature shows that opinions on the effect of the various nutrients differ markedly. The conclusion which can be made is that in countries where standards of dairy farming are high, nutrition only plays a minor role in the problem of herd subfertility. In the course of time deficiencies in a large number of minerals, trace elements and vitamins have been stressed as a cause of inadequate fertility. However cows are at present generally fed with a lot of well balanced concentrates and therefore deficiencies are very unlikely to occur. During early lactation every high producing dairy cow has a negative energy balance. In a number of cows this results in anoestrus and in a long interval from parturition to first insemination. Overfeeding during late lactation and the dry period does not adversely affect subsequent reproduction but may cause puerperal disorders. The relation between protein nutrition and fertility is complex. Protein effects on fertility are minor. Problems can arise if there is a combination of a high percentage of crude protein (greater than 18%), a high rumen degradability of the protein and a low energy content of the diet. The value of metabolic profile tests is minimal because they do not differentiate between normal herds and herds with fertility problems. 相似文献
306.
Twenty-nine pruritic, atopic dogs were entered into a double-blind, placebo-controlled, crossover study to evaluate the efficacy of an investigational antiallergenic compound, AHR-13268. Fourteen dogs were evaluated by a veterinary dermatologist (at intervals) and the owner (daily). Fifteen dogs were evaluated only by the owner. The mean (+/- SE) owner scores for pruritus, erythema, and lesions with placebo treatment (higher score = worse signs) were 3.24 (+/- 0.12), 2.73 (+/- 0.12), and 2.61 (+/- 0.09), respectively. With drug treatment, the corresponding scores were 2.89 (+/- 0.12), 2.50 (+/- 0.12), and 2.25 (+/- 0.09). Scores for pruritus and lesions (but not erythema) were significantly better with drug treatment than with placebo treatment. Investigator scores showed similar trends, but the differences were not great enough to be statistically significant. Overall, 11/29 (38%) owners reported their dogs had moderate or better improvement from drug capsules, and 4/29 dogs (14%) improved on placebo capsules. A variety of adverse effects were reported following both drug (9/29 dogs) and placebo (8/29 dogs) capsule administration, but were mild and well tolerated. Results of this study indicate that AHR-13268 has potential for empiric treatment of allergic inhalant dermatitis in some dogs. 相似文献
307.
Bilateral nephrolithiasis with intermittent ureterolithiasis was diagnosed in a 7-year old Holstein cow. Two episodes of ureterolithiasis resulted in severe azotemia which resolved after spontaneous movement of the stone. A third episode of obstruction one year after the initial episode resulted in rupture of one kidney, necessitating euthanasia. The histopathological examination of the kidney was diagnostic for chronic pyelonephritis. Corynebacterium sp. was cultured from a nephrolith. In this case it is believed that the chronic pyelonephritis predisposed to the calculi formation. 相似文献
308.
KENNETH A. BRUECKER DVM MS HOWARD B. SEIM III DVM DiplomateACVS STEPHEN J. WITHROW DVM DiplomateACVS 《Veterinary surgery : VS》1989,18(3):197-203
Sixty-four dogs with caudal cervical spondylomyelopathy (CCSM) caused by chronic degenerative disc disease were treated with ventral decompression (n = 20), linear traction and interbody screw stabilization (n = 7), or linear traction and plastic plate stabilization (n = 37). Interbody screw stabilization was ineffective in treating CCSM because of an unacceptably high rate of implant failures. Ventral decompression or linear traction and plastic plate stabilization were effective in the treatment of most patients with mild to moderate neurologic deficits (neck pain, paraparesis, or ambulatory tetraparesis). Although these techniques were also used successfully in some patients with severe neurologic deficits (weakly ambulatory tetraparesis or nonambulatory tetraparesis), variable success rates and prolonged postoperative recovery periods were noted. 相似文献
309.
Uterine response to inoculation with Streptococcus zooepidemicus organisms, 51Cr-labeled 15-microns microspheres, and charcoal was evaluated in 9 mares (4 resistant and 5 susceptible to endometritis) to determine mechanical and cellular clearance rates during the early postovulatory period. Mares were inoculated at estrus prior to ovulation during estrous cycles 1, 3, and 5. Uterine swab specimens for aerobic and anaerobic bacteriologic culture and serum for progesterone determination were obtained on postovulation day 3 during estrous cycle 1, on the day of ovulation during estrous cycle 3, and on postovulation day 5 during estrous cycle 5. Immediately thereafter, the uterus was irrigated with 50 ml of sterile physiologic saline solution containing tracer amounts of 125I-labeled human serum albumin. Streptococcus zooepidemicus was isolated from 10 of 15 (67%) uterine specimens collected from susceptible mares and incubated aerobically. Escherichia coli also was isolated from 2 of the 10 specimens incubated aerobically. Anaerobic bacteriologic culture of specimens from all mares yielded no growth. Chromium-labeled microspheres were recovered twice from 2 susceptible mares, on day 0 and day 5. Charcoal was retained in 5 specimens collected from 3 susceptible mares. Bacteriologic culture of specimens from resistant mares did not yield growth. On day 0, chromium-labeled microspheres and charcoal were recovered once from 1 resistant mare. Mares susceptible to endometritis accumulated more fluid within the uterine lumen after ovulation than did resistant mares (mean +/- SEM, 52.73 +/- 15.22 ml and 7.41 +/- 1.96 ml, respectively; P less than 0.01). From this study, it appeared that uterine cellular and bactericidal mechanisms are dysfunctional during the early postovulatory period. However, there appeared to be no disruption of the mechanisms responsible for mechanical clearance of materials inoculated in the uterus. 相似文献
310.
Bovine neutrophil chemotactic activity was detected in the supernatant fluid of logarithmic phase cultures of P. haemolytica serotype 1. The chemoattractant was produced under culture conditions suitable for P. haemolytica leukotoxin production. An inverse correlation existed between the leukotoxin LC50 and the chemotactic activity in the culture fluid. Elimination of leukotoxin activity by heating, dilution or ultrafiltration, exposed the chemotactic activity in the culture fluid. The chemoattractant was partially resistant to heating (60 degrees C, 30 min), and had an apparent molecular weight greater than 100,000. Detection of chemotactic activity in both the concentrate and filtrate after XM300 filtration suggested that there might be more than one component with chemotactic activity or else that polymerization was occurring. Production of a potent neutrophil chemoattractant by P. haemolytica may explain the rapid infiltration of neutrophils that occurs during the early stages of bovine pneumonic pasteurellosis. 相似文献