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971.
Arnett EJ Fluharty FL Loerch SC Zerby HN Zinn RA Kuber PS 《Journal of animal science》2012,90(3):960-972
Jersey cattle are known for producing carcasses with a greater amount of marbling, but they require more days on feed to achieve acceptable market weights compared with other breeds. The objective of this study was to evaluate the effect of dietary forage (12 vs. 24% sudangrass:alfalfa hay, DM basis) in steam-flaked, corn-based finishing diets on carcass characteristics, beef palatability, and retail color stability of steaks from Jersey beef compared with conventionally fed commodity beef strip loins (COM) of identified quality (Choice(-) and Select(+)). Jersey steers (n = 77) were blocked by BW and randomly assigned to 1 of the following treatments for a 383-d trial period: Jersey low 12% (JL; n = 38) or Jersey high 24% (JH; n = 39) forage (DM basis). A comparison group was selected from conventionally fed cattle on the same day of slaughter as the Jersey treatments, and strip loins from USDA Select(+) (COM; n = 20) and Choice(-) (COM; n = 20) were removed for data analysis. Seventy-two hours postmortem, strip loins were removed, vacuum-packaged, and aged at 3°C for 18 d postmortem. After the aging period, steaks from the LM were sliced, vacuum-packaged, and frozen (-20°C) until analyzed. Jersey steaks had reduced (P < 0.05) Warner-Bratzler shear force values compared with COM steaks. Trained sensory panelists rated JL greater (P < 0.05) for initial and sustained tenderness and initial juiciness than COM, whereas JH was intermediate. As expected, marbling was greater (P < 0.05) for both JL and JH compared with COM, and trained sensory panel sustained juiciness, beef flavor intensity, and overall acceptability scores were greater (P < 0.05) for both JL and JH compared with COM; however, no differences (P = 0.14) were reported for consumer tenderness and flavor. Objective color (L*, a*, b*) measurements decreased (P < 0.05) over time across treatments. There were no differences among treatments for lightness (L*); however, overall during retail display JL were less (P < 0.05) red (a*) and yellow (b*) than JH and COM. Subjective color scores indicated both JL and JH were less red (P < 0.05) than COM. Steaks from Jersey were equal to and on some measurements more desirable than steaks from COM carcasses for both color stability and palatability. These results suggest that dietary forage level had minimal effects on carcass characteristics and beef palatability. However, feeding a low-forage diet decreases input cost and potentially results in a greater valued carcass. Finishing long-fed (383 d) Jersey steers can meet beef industry expectations with respect to quality grade. 相似文献
972.
Effects of feeding high-oil corn to beef steers on carcass characteristics and meat quality 总被引:4,自引:0,他引:4
To assess the effects of feeding high-oil corn on carcass characteristics and meat quality, 60 yearling steers were fed high concentrate diets containing either control corn (82% of diet), high-oil corn (82% of diet), or high-oil corn at a concentration that was isocaloric with the control diet (74% of diet). After being fed for 84 d, steers were slaughtered. At 72 h postmortem, carcass data were collected and rib sections from five steers grading U.S. Choice and five steers grading U.S. Select from each treatment were collected, vacuum packaged, and aged for 14 d. Three steaks (2.54 cm thick) were removed from each rib for Warner-Bratzler shear force measurement, sensory appraisal, and fatty acid composition analyses. Data were analyzed with treatment as the main effect for the carcass data and treatment, quality grade, and two-way interaction in the model for the longissimus data. The two-way interaction was nonsignificant (P > 0.05) for all variables tested. No differences were detected (P > 0.05) in carcass measurements except for marbling scores and quality grades, both of which were greater (P < 0.05) for carcasses from steers fed the high-oil corn. Overall, 78% of steers fed the high-oil corn graded U.S. Choice compared with 47% for the control and 67% for isocaloric group. Shear force and sensory properties of the longissimus were not different (P > 0.05) among treatments. Steaks from U.S. Choice carcasses rated higher (P < 0.05) for tenderness and tended to rate higher (P < 0.10) for juiciness. Feeding the isocaloric and high-oil diets increased (P < 0.05) linoleic acid, arachidonic acid, and the total PUFA content of lipid extracted from the longissimus. Saturated fatty acid percentage was lowest (P < 0.05) for high-oil corn and highest (P < 0.05) for control, with isocaloric being intermediate. Feeding high-oil corn increased (P < 0.05) pentadecyclic acid, margaric acid, and total odd-chain fatty acid content. Feeding high-oil corn in finishing beef cattle diets enhanced intramuscular lipid deposition and increased unsaturation of fatty acids of the longissimus. 相似文献
973.
Photosynthesis in the shoots of winter wheat (Triticum aestivum L.) was inhibited by certain phenylurea herbicides applied via the nutrient solution. Recovery from this inhibition after short treatments was used as a measure of the rate of inactivation of these herbicides in the leaf tissue of a variety tolerant to metoxuron (Caribo) and of a less tolerant variety (Manella). The introduction of chlorine atoms into fenuron greatly reduced the rate of inactivation in both varieties, whereas that of a methyl or butoxy group had little or no effect. Metoxuron was inactivated more readily than chlortoluron and both compounds were inactivated more rapidly in Caribo than in Manella. 相似文献
974.
Changying Li Gerard W. Krewer Pingsheng Ji Harald Scherm Stanley J. Kays 《Postharvest Biology and Technology》2010,55(3):144-149
A conducting polymer gas sensor array (electronic nose) was evaluated for detecting and classifying three common postharvest diseases of blueberry fruit: gray mold caused by Botrytis cinerea, anthracnose caused by Colletotrichum gloeosporioides, and Alternaria rot caused by Alternaria sp. Samples of ripe rabbiteye blueberries (Vaccinium virgatum cv. Brightwell) were inoculated individually with one of the three pathogens or left non-inoculated, and volatiles emanating from the fruit were assessed using the gas sensor array 6–10 d after inoculation in two separate experiments. Principal component analysis of volatile profiles revealed four distinct groups corresponding to the four inoculation treatments. MANOVA, conducted on profiles from individual assessment days or from combined data, confirmed that the four treatments were significantly different (P < 0.0001). A hierarchical cluster analysis indicated two super-clusters, i.e., control cluster (non-inoculated fruit) vs. pathogen cluster (inoculated fruit). Within the pathogen cluster, fruit infected by B. cinerea and Alternaria sp. were more similar to each other than to fruit infected by C. gloeosporioides. A linear Bayesian classifier achieved 90% overall correct classification for data from experiment 1. Tenax? trapping of volatiles with short-path thermal desorption and quantification by gas chromatography–mass spectrometry was used to characterize volatile compounds emanated from the four groups of berries. Six compounds [styrene, 1-methyl-2-(1-methylethyl) benzene, eucalyptol, undecane, 5-methyl-2-(1-methylethyl)-2-cyclohexen-1-one, and thujopsene] were identified as contributing most in distinguishing differences in the volatiles emanating from the fruit due to infection. A canonical discriminant analysis model using the relative concentration of each of these compounds was developed and successfully classified the four categories of berries. This study underscores the potential feasibility of using a gas sensor array for blueberry postharvest quality assessment and fungal disease detection. 相似文献
975.
976.
977.
MANON PARADIS SUZIE LEMAY DANNY W. SCOTT WILLIAM H. MILLER JOCELYN WELLINGTON RADA PANICH 《Veterinary dermatology》1990,1(3):123-127
Abstract— Bacterial pyoderma was diagnosed in 30 dogs which were subsequently treated with enrofloxacin administered orally at 2.5 mg.kg-1 of body weight every 12 h, for 2 to 14 weeks. Dogs were re-examined at the conclusion of antibiotic treatment and 28 (93.3 per cent) were found to have an excellent response. Relapses were seen in 25 per cent of these dogs after follow up periods of 1 to 4 months. Minor side effects were seen in only 1 dog. On the basis of this study, enrofloxacin is an excellent antibiotic for the treatment of canine bacterial pyoderma but must be administered well beyond the manufacturer's maximum recommendation for duration of therapy. Résumé— Une pyodermite bactérienne a été diagnostiquée chez 30 chiens qui furent traités avec de l'enrofloxacine administrée par voie orale à la dose de 2.5 mg/Kg toutes les 12 heures, pour une durée allant de 2.5 à 14 semaines. Les chiens furent réexaminés à la fin de l'antibiothérapie et 28 d'entre eux (93.3%) présentaient une excellente réponse au traitement. Des rechutes furent observées chez 25% des chiens lors de suivis portant sur des périodes de 1 à 4 mois. Des effets secondaires mineurs furent observés chez l'un des chiens. Cette étude montre que l'enrofloxacine est un excellent antibiotique pour le traitement des pyodermites canines mais, qu'il doit être administré pendant des délais beaucoup plus longs que ceux qui sont indiqués par le fabricant. Zusammenfassung— 30 Hunde mit bakteríellen Pyodermien wurden zweieinhalb bis vierzehn Wochen lang oral mit Enrofloxacin behandelt (2 täglich 2.5 mg/kg KGW). Nach Abschluß der Behandlung wurden die Tiere erneut untersucht. Bei 28 Patienten (93.3%) wurden hervorragende Ergebnisse erzielt. Bei 25% kam as nach 1 bis 4 Monaten zu Rezidiven. Geringe Nebenwirkungen wurden nur in einem Fall beobachtet. Die vorliegende Untersuchung zeigt, daß Enrofloxacin ein hervorragendes Antibiotikum für die Behandlung von Pyodermien ist, aber wesentlich länger als vom Hersteller angegeben verabreicht werden muß. Resumen Treinta perros, a los cuales se había diagnosticado una epiderma bacteriana, fueron tratado con Enrofloxacina via oral a una dosis de 2,5 mg/kg de peso corporal cada 12 horas durante un período de tiempo que oscíló entre las 2,5 semanas y las 14 semanas. Los perros se examinaron clínicamente de nuevo cuando acabó el tratamiento antibiótico y se observó en 28 (93,3%) una respuesta excelente. En un 25% de estos perros se observaron recidivas en un período comprendido entre uno y cuatro meses. Efectos colaterales de poca importancia se observaron úicamente en un animal. Según estos resultados puede concluirse que la Enrofloxacina es un antibiótico excelente para el tratamiento de las piodermas bacterianas del perro, aunque debe administrarse durante un período de tiempo superior al que recomiendan los productores. 相似文献
978.
Stallknecht DE Greer JB Murphy MD Mead DG Howerth EW 《American journal of veterinary research》2004,65(9):1233-1239
OBJECTIVE: To determine whether pigs can be infected with strains of vesicular stomatitis virus New Jersey (VSV-NJ) and vesicular stomatitis virus Indiana (VSV-I) isolated during recent vesicular stomatitis outbreaks that primarily involved horses in the western United States and determine the potential for these viruses to be transmitted by contact. ANIMALS: 128 pigs. PROCEDURE: Pigs were challenged with VSV-NJ or VSV-I from the 1995 and 1997 outbreaks of vesicular stomatitis in the western United States, respectively, or with VSV-NJ (OS) associated with vesicular stomatitis in feral pigs on Ossabaw Island, Ga. Pigs (3/group) were inoculated with each virus via 3 routes and evaluated for viral shedding, seroconversion, and the development of vesicular lesions. In another experiment, the potential for contact transmission of each virus from experimentally infected to na?ve pigs was evaluated. RESULTS: Infection of pigs was achieved for all 3 viruses as determined by virus isolation and detection of seroconversion. In inoculated pigs, all 3 viruses were isolated from multiple swab samples at concentrations sufficient to infect other pigs. However, compared with results obtained with the 2 VSV-NJ strains, viral titers associated with VSV-I were low and the duration of virus shedding was reduced. Results from the contact transmission trials were consistent with these results; virus transmission was detected most frequently with the VSV-NJ strains. CONCLUSIONS AND CLINICAL RELEVANCE: Pigs can be infected with VSV-NJ and VSV-I. Differences in the extent of viral shedding and potential for contact transmission were apparent between serotypes but not between the VSV-NJ strains investigated. 相似文献
979.
Kura clover (Trifolium ambiguum M.B.) is a perennial rhizomatous forage legume whose use is currently limited by difficulties in its establishment in part attributable to nodulation problems and very specific rhizobial requirements. A limited number of Kura clover-nodulating rhizobial strains are currently available and many have a limited effectiveness. In this study, 128 rhizobia were isolated from four sites in the center of origin of Kura clover (i.e., two in Azerbaijan, one in Armenia, and one in Northwest Iran) using the three ploidy levels of Kura clover (diploid, tetraploid, and hexaploid), red clover (Trifolium pratense L.), and white clover (Trifolium repens L.) plants as trap hosts. Rhizobia were fingerprinted using repetitive extragenic palindromic polymerase chain reaction (BOXA1R primer) and their genetic diversity was measured using the Shannon-Weaver diversity index. The nodulation specificity and phenotypic diversity of a subset of 13 isolates was determined. Genetic diversity among the 128 isolates was large and similar for rhizobia grouped according to their geographic origin or original host plant. Phenotypic diversity was significant; percentage of similarity among 13 isolates ranging between 38 and 92%. Nodulation specificity of the Kura clover-nodulating rhizobial isolates studied was less complex and not as clearly delineated as previously reported. Some strains originally isolated from Kura clover could effectively nodulate more than one ploidy level of Kura clover and even one or both of two other Trifolium species (i.e., red clover and white clover). Three strains formed effective nodules on both Kura clover and white clover; however, none promoted plant growth of both species to levels currently obtained with commercial inoculants when evaluated in a growth chamber. Rhizobial isolates that are highly effective with both species have yet to be identified. 相似文献
980.
An index of the buffering capacity for phosphate of a group of soils was obtained by measuring adsorption of phosphate from dilute solutions of calcium chloride. The effect of buffering capacity on the amount of phosphate initially displaced by solutions of sodium bicarbonate and on the amount of secondary adsorption from bicarbonate was then studied. These two effects were separated using a regression procedure in which the soil: solution ratio was the independent variable.As buffering capacity increased the amount of phosphorus initially displaced decreased and the amount of secondary adsorption increased. Both these changes resulted in a decrease in the amount of phosphate in the extract. The effect of buffering capacity was greater with the Olsen method (soil : solution ratio 1 : 20; 30 min) than with the Colwell method (soil : solution ratio 1 : 100; 16 h). The relation between phosphorus extracted and buffering capacity was of a similar shape to that between effectiveness of fertilizer and buffering capacity. However, the first relation depends on the conditions of extraction and the second on the kind of plant grown and on the conditions of growth. Hence the two relations do not necessarily coincide.The effect of buffering capacity on the proportion of added phosphate initially displaced from the soil became more marked as the period of incubation prior to extraction was increased. Bicarbonate soil tests would therefore indicate that, on soils of low buffering capacity, the decrease with time in availability of applied phosphate would be smaller than on soils of high buffering capacity. This effect differs from that observed with plants. 相似文献