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981.
The effect of various disease-vector control alternatives on the prevalence of trypanosomiasis in southwest Ethiopia was examined with the aid of an epidemiologic model. The alternatives considered included vegetation clearing by manual labor, game elimination, insecticidal spraying from airplanes coupled with settlement, use of sterile male Glossina, avoidance of tsetse infested areas, increasing the resistance of the cattle population, therapy, and combinations of the above methods. First, the currently estimated endemic prevalence of trypanosomiasis (27.3%) in the simulated area of Ethiopia was established and maintained over a 10 year period. Then, various control alternatives were introduced and the simulation was run for an additional 10 years to observe the effect of these control alternatives on the prevalence. The combined use of vegetation clearing, insecticides, therapy, and settlement (or resettlement) was the most effective and feasible method of trypanosomiasis control for the simulated situation.  相似文献   
982.
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   
983.
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   
984.
Phenobarbital is the drug of choice for control of canine epilepsy. Phenobarbital induces hepatic enzyme activity, can be hepatotoxic, and decreases serum thyroxine (T4) concentrations in some dogs. The duration of liver enzyme induction and T4 concentration decreases after discontinuation of phenobarbital is unknown. The purpose of this study was to characterize the changes in serum total T4 (TT4), free T4 (FT4), thyroid-stimulating hormone (TSH), cholesterol and albumin concentrations, and activities in serum of alanine aminotransferase (ALT), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) after discontinuation of long-term phenobarbital administration in normal dogs. Twelve normal dogs were administered phenobarbital at a dosage of approximately 4.4-6.6 mg/kg PO q12h for 27 weeks. Blood was collected for analysis before and after 27 weeks of phenobarbital administration and then weekly for 10 weeks after discontinuation of the drug. The dogs were clinically normal throughout the study period. Serum ALT and ALP activity and TSH and cholesterol concentrations were significantly higher than baseline at week 27. Serum T4 and FT4 were significantly lower. Serum albumin and GGT were not changed from baseline at week 27. Changes in estimate of thyroid function (TT4, FT4, TSH) persisted for 1-4 weeks after discontinuation of phenobarbital, whereas changes in hepatic enzyme activity (ALT, ALP) and cholesterol concentration resolved in 3-5 weeks. To avoid false positive results, it is recommended that thyroid testing be performed at least 4 weeks after discontinuation of phenobarbital administration. Elevated serum activity of hepatic enzymes 6-8 weeks after discontinuation of phenobarbital may indicate hepatic disease.  相似文献   
985.
1. The objective of this study was to evaluate whether the oligosaccharide stachyose enhances gastrointestinal tract health by fermentation and proliferation of desirable bacteria species and thus affects growth performance and nutrient digestibility in broilers. 2. A total of 432 1-d-old male Arbor Acres (AA) broilers were randomly allocated to one of 6 treatments, with 12 replicate pens per treatment and 6 birds per pen. Chicks were fed a maize-hamlet protein 300 (HP300) basal diet with 0, 4.0, 8.0, 12.0 or 16.0 g/kg stachyose. A sixth diet contained no HP300 but soybean meal (SBM) and provided 8.7 g/kg stachyose and 3.1 g/kg raffinose. The duration of the study was 42 d. 3. Stachyose contents above 12.0 g/kg depressed group body weights, average daily gain and feed/gain but not feed intake during the whole experimental period. Broiler growth decreased linearly and quadratically with increasing stachyose content. No differences were detected between diets supplemented with 12.0 g/kg stachyose and SBM. 4. Nutrient digestibility tended to decrease but not significantly with increasing stachyose. 5. Stachyose content had no significant positive effects on caecal pH, microflora population and the resulting short-chain fatty acid (SCFA) metabolites during the 42 d experiment, with only butyrate differing significantly in the initial period.  相似文献   
986.
Efficacy of Enrofloxacin in the Treatment of Canine Bacterial Pyoderma   总被引:1,自引:0,他引:1  
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   
987.
988.
Tractor rollovers continue to be one of the most frequent causes of agricultural fatalities. Despite knowledge of rollovers and the efficacy of rollover protective structures (ROPS), few New York farmers have considered installing ROPS on their unprotected tractors. Qualitative interviews conducted with an "at-risk" segment of the New York farming community indicate that there are a number of barriers to safety in general and to retrofitting, in particular. The following themes and categories emerged in relation to safety and risk taking: constant exposures to risk with positive outcomes normalizes risk; the modeling of risk by significant others positions risk as part of a farming identity; and the pressure to reduce costs, save time, and accept risk frames risk-taking as the cost-effective option (especially in regard to retrofitting, which farmers believe is both expensive and time-consuming). Recommendations for researchers planning retrofitting interventions would be to focus safety messages on the risk to significant others or on the financial impact of rollovers, and to provide financial incentives and assistance to farmers considering retrofitting.  相似文献   
989.
The effect of microbial phytase on phosphorus utilization in juvenile Clarias gariepinus (initial fish body weight 11.55 ± 0.2 g) was tested on two different diets based on oil-extracted soya bean (Experiment 1) and roasted soya bean meal (Experiment 2) using a 5 × 5 experimental design for 84 days. The basal isonitrogenous and isocaloric diets for oil-extracted and roasted soya bean were formulated to replace fish meal at 25% (S1E), 50% (S2E), 75% (S3E), 100% (S4E); and 25% (S1), 50% (S2), 75% (S3), 100% (S4), respectively. Each treatment was replicated four times. Microbial phytase was supplemented in each replicate at 250 FTU/g (P1), 500 FTU/g (P2), 750 FTU/g (P3), and 1,000 FTU/g (P4). Basal controls, which included a fish meal-based diet (S0), were not supplemented with phytase (P0). The result in Experiment 1 showed that there was a significant increase in whole-body protein and reduction in fat with phytase compared to a diet without phytase (P < 0.05). Serum total protein declined significantly with phytase supplementation (P < 0.05). Serum phosphorus and glucose were higher with phytase supplementation compared to control (P < 0.05). Bone minerals declined significantly with increasing level of soya bean compared to fish meal diet (P < 0.05). In Experiment 2, serum phosphorus was improved with phytase compared to control with no phytase (P > 0.05). A significant reduction in whole-body protein and increase in fat was observed for fish fed phytase diets compared to diets with no phytase, regardless of soya bean level (P < 0.05); however, ash content was improved with phytase (250 FTU/g) compared to control (P < 0.05). Phytase supplementation improved bone phosphorus (250 FTU/g), calcium (250 FTU/g), magnesium (250–500 FTU/g), and zinc (250–1,000 FTU/g) compared to control (P < 0.05). In conclusion, the research has demonstrated that improved bone phosphorus (P) and growth could be achieved with the supplementation of dietary phytase.  相似文献   
990.
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