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891.
Preliminary investigation of the probiotic potential of Lactobacillus rhamnosus strain GG in horses: fecal recovery following oral administration and safety
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Weese JS Anderson ME Lowe A Monteith GJ 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(4):299-302
This study was designed to evaluate whether Lactobacillus rhamnosus strain GG (LGG), an extensively studied probiotic organism in humans, can colonize the intestines of adult horses and foals. Lactobacillus rhamnosus strain GG was administered to adult horses at doses of 1 x 10(9) CFU/50kg bodyweight (BW)/day (group 1, 7 horses), 1 x 10(10) colony forming units/ 50kg BW/day (group 2, 7 horses) and 5 x 10(10) colony forming units/50kg BW/day (group 3, 7 horses) for 5 d. Foals received 2 x 10(10) colony forming units/50kg BW/day (group 1, 7 foals) or 1 x 10(11) colony forming units/50kg BW/day (group 2, 7 foals) for 5 d. Fecal levels of L. rhamnosus strain GG in adult horses were low and variable in the 2 lower dose groups. Even in the high dose group, colonization was relatively low. In contrast, more consistent intestinal colonization was present in foals, and colonization persisted for up to 9 d following cessation of administration. No adverse effects were observed in any animal. Clinical studies evaluating this probiotic are indicated in foals. The presence of this organism in the feces of adult horses may only represent passive movement through the intestinal tract, not actual colonization. Consistent intestinal colonization in adults was only achieved with a prohibitively high dose. 相似文献
892.
893.
Scott TL Milton CT Erickson GE Klopfenstein TJ Stock RA 《Journal of animal science》2003,81(12):3182-3190
Two trials were conducted to determine the effect of corn processing method on performance and carcass traits in steers fed finishing diets containing wet corn gluten feed (WCGF). In Trial 1, 480 steer calves (303 kg initial BW) were fed eight finishing diets: 1) dry-rolled corn (DRC) without; and 2) with 32% (DM basis) WCGF; 3) steam-flaked corn (SFC) without; and 4) with WCGF; 5) a combination of DRC and SFC without WCGF; 6) finely-ground corn (FGC) with WCGF; 7) high-moisture corn (HMC) with WCGF; and 8) whole corn (WC) with WCGF. Feeding WC + WCGF increased (P < 0.10) DMI and decreased gain:feed compared with all other treatments. Feeding DRC + WCGF increased (P < 0.10) DMI and decreased (P < 0.10) gain:feed compared with treatments other than WC + WCGF. Steers on treatments that included WCGF gained similarly, regardless of corn processing method, and at a rate 6% faster (P < 0.10) than steers fed diets that did not include WCGF. Gain:feed did not differ among steers fed SFC, SFC + WCGF, SFC + DRC, and HMC + WCGF. Steers fed SFC or SFC + WCGF were more efficient (P < 0.10) than steers fed DRC or FGC + WCGF. In Trial 2, 288 steer calves (382 kg initial BW) were fed six finishing diets: 1) DRC without; and 2) with 22% (DM basis) WCGF; 3) SFC without; and 4) with WCGF; 5) finely rolled corn (FRC) with WCGF; and 6) HMC corn with WCGF. Steers fed DRC + WCGF or FRC + WCGF consumed more DM (P < 0.10) than steers fed DRC, SFC, or SFC + WCGF. Feed intake did not differ between steers fed SFC + WCGF and HMC + WCGF. All treatment groups receiving WCGF consumed more DM (P < 0.10) feed than steers fed DRC or SFC without WCGF. Steers fed SFC + WCGF gained 8% faster (P < 0.10), and steers fed DRC 9.5% slower (P < 0.10) than steers receiving all other treatments. Daily gains did not differ among other treatment groups. Steers fed SFC or SFC + WCGF gained 10% more (P < 0.10) efficiently than all other treatment groups. Feed efficiency did not differ among steers fed DRC, DRC + WCGF, FRC + WCGF, and HMC + WCGF. Estimates for the NEg of WCGF calculated from animal performance indicated that WCGF contained approximately 25.3% more energy when fed with SFC than when fed with DRC. In general, more intensively processing corn improved gain:feed in finishing diets containing WCGF. 相似文献
894.
Nolen RS 《Journal of the American Veterinary Medical Association》2003,222(3):271-272
895.
Duxbury MM Jackson JA Line SW Anderson RK 《Journal of the American Veterinary Medical Association》2003,223(1):61-66
OBJECTIVE: To evaluate associations between retention of dogs in their adoptive homes and attendance at puppy socialization classes and other factors. DESIGN: Epidemiologic survey. ANIMALS: 248 adult dogs that were adopted as puppies from a humane society. PROCEDURE: Owners completed questionnaires regarding demographics, retention of the dogs in the homes, and the dogs' early learning events. RESULTS: Higher retention in the homes was reported for dogs that participated in humane society puppy socialization classes, were female, wore headcollars as puppies, were handled frequently as puppies, were more responsive to commands, slept on or near the owner's bed, or lived in homes without young children. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest several practices that veterinarians may recommend to enhance the likelihood that puppies will remain in their first homes, such as enrolling 7- to 12-week-old puppies in early learning and socialization classes. The lower rate of retention of dogs in homes with children emphasizes the importance of helping owners develop realistic expectations, knowledge, and effective tools to manage interactions between their children and dogs. 相似文献
896.
897.
Estimating the ‘critical’ distance at which adjacent land-use degrades wetland water and sediment quality 总被引:1,自引:0,他引:1
Conversion of forested lands to agriculture or urban/residential areas has been associated with declines in stream and lake water quality. Less attention has been paid to the effects of adjacent land-uses on wetland sediment and water quality and, perhaps more importantly, the spatial scales at which these effects occur. Here we address these issues by examining variation in water and sediment nutrient levels in 73 southeastern Ontario, Canada, wetlands. We modeled the relationship between water and sediment nutrient concentrations and various measures of adjacent land-use such as forest cover and road density, measured over increasing distances from the wetland edge. We found that water nitrogen and phosphorous levels were negatively correlated with forest cover at 2250 meters from the wetland edge, while sediment phosphorous levels were negatively correlated with wetland size and forest cover at 4000 meters and positively correlated with the proportion of land within 4000 meters that is itself wetland. These results suggest that the effects of adjacent land-use on wetland sediment and water quality can extend over comparatively large distances. As such, effective wetland conservation will not be achieved merely through the creation of narrow buffer zones between wetlands and more intensive land-uses. Rather, sustaining high wetland water quality will require maintaining a heterogeneous regional landscape containing relatively large areas of natural forest and wetlands. 相似文献
898.
Evolutionary plasticity of monooxygenase-mediated resistance 总被引:1,自引:0,他引:1
The cytochrome P450 monooxygenases are an important metabolic system involved in the detoxification of xenobiotics, and are thus one of the major mechanisms by which insects evolve insecticide resistance. However, comparatively little is known about the evolutionary constraints of this insecticide resistance mechanism. We investigated the genetic basis of resistance in a strain of house fly (NG98) from Georgia, USA that had evolved 3700-fold resistance to the pyrethroid insecticide permethrin, and compared this to other permethrin resistant strains of house flies from the US and Japan. Resistance in NG98 was due to kdr on autosome 3 and monooxygenase-mediated resistance on autosomes 1, 2, and 5. These results indicate that the genes which evolve to produce monooxygenase-mediated resistance to permethrin are different between different populations, and that the P450 monooxygenases have some degree of plasticity in response to selection. Monooxygenase-mediated resistance appears to evolve using different P450s, and possibly different regulatory signals controlling P450 expression, even in strains selected with the same insecticide. 相似文献
899.
Christopher P. Cook Danny W. Scott William H. Miller Jr. J. Edward Kirker Shaun M. Cobb 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(5):414-417
Cetirizine and placebo were administered orally as individual agents to 23 dogs with atopic dermatitis. The pruritus was satisfactorily reduced in 4/22 (18%) dogs that completed the trial with cetirizine. Two dogs vomited after administration of the active drug. 相似文献
900.
Scott Willens J Lawrence Dunn Salvatore Frasca 《Journal of zoo and wildlife medicine》2004,35(1):107-109
An adult, male, captive lined seahorse (Hippocampus erectus) was presented with weight loss, anorexia, and brood pouch distention. Initial treatments included manual expression of the brood pouch followed by saline flushes and enrofloxacin infusions. Radiographs and physical examination identified a nodular swelling in the brood pouch wall. The mass was excised, but the seahorse died. Necropsy and histopathology revealed a malignant mesenchymal tumor with a collagenous stroma, and a brood pouch fibrosarcoma was diagnosed. 相似文献