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71.
Efficacy of an in-feed ivermectin formulation against gastrointestinal helminths, lungworms, and sarcoptic mites in swine 总被引:1,自引:0,他引:1
R Alva-Valdes D H Wallace A G Foster G F Ericsson J W Wooden 《American journal of veterinary research》1989,50(8):1392-1395
The efficacy of ivermectin as an in-feed formulation was evaluated against naturally acquired gastrointestinal helminths, lungworms, and sarcoptic mites (experiment 1; n = 24) and against induced infection with intestinal nematodes (experiment 2; n = 24) in pigs. Treatments consisted of ivermectin administered in feed at concentrations calculated to provide 100 or 200 micrograms/kg of body weight/d for 7 days or of nonmedicated feed (controls) for 7 days. At concentration of 100 micrograms of ivermectin/kg/d, efficacy against naturally acquired infections was 97.7% for Ascaris suum, 97.8% for Metastrongylus spp, greater than 99% for Oesophagostomum spp, 100% for Macracanthorhynchus hirudinaceus, and 89.7% for Ascarops strongylina. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 96.9% for Oesophagostomum spp. At concentration of 200 micrograms of ivermectin/kg/d, efficacy against naturally acquired infections was 100% for A suum, Hyostrongylus rubidus, Metastrongylus spp, and Ascarops strongylina; greater than 99% for Oesophagostomum spp; and 85.9% for Macracanthorhynchus hirudinaceus. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 95% for Oesophagostomum spp. At concentrations of 100 and 200 micrograms of ivermectin/kg/d, efficacy against Sarcoptes scabiei var suis was evidenced by elimination of the mite by posttreatment day 14. 相似文献
72.
W. H. Foster 《British poultry science》1967,8(3):201-207
An analysis was performed on the published results of the first, second and third Gosford Random Sample Tests to determine which of the various biological traits reported had the greatest influence upon the overall ranking. Ten traits were considered. It was found that regression on survivors’ average egg production and laying house mortality removed 88.1 per cent of the variation in financial return. The addition of average egg weight and daily food consumption increased this figure to 93.3 per cent. The remaining traits, number of unsaleable birds at 500 days, body weight at 500 days, age at 50 per cent production, blood spots, meat spots and shell thickness, did not produce significant reductions except in so far as they were correlated with those previously mentioned.
The financial returns expected from improvements in the four important traits were:
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Per bird
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+ 12 in survivors egg production 2S. 4¼d. ± 1¼d.
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—5 in percentage laying mortality is. 5d.± 1d.
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+ 1 g. in average egg weight 10½d. + 1 ½d.
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—5 g. in food consumed per day 43/4d.± 1¼d.
Laying house mortality was found to be positively correlated among the entries with survivors’ average egg production and with average egg weight. 相似文献
73.
74.
W. H. Foster 《British poultry science》1980,21(4)
Commercial Chicken Production Manual, 2nd edition, by Mack, O. North. Avi Publishing Co., Inc., Westport, Conn., USA, 1978. 692 pp. Price $42.50. 相似文献
75.
76.
77.
78.
W. H. Foster 《British poultry science》1968,9(3):273-284
An experiment is described conducted on approximately 1000 pullets from six different strains over a period of almost one year. The three treatments used were cycles of 23, 24 and 25 hr composed of 15 light:8 dark, 15 light:9 dark and 15¼ light:9¾ dark. Egg production increased significantly (P <0.01) with increasing cycle length, the mean rates of lay, expressed as eggs per 100 birds per 24 hr, being 71.6, 72.9 and 73.8 for the 23‐, 24‐ and 25‐hr cycles respectively.
The relative effects of the treatments were found to remain unaltered throughout the experiment. 相似文献
79.
Hewitt SA Brisson BA Sinclair MD Foster RA Swayne SL 《Journal of the American Veterinary Medical Association》2004,225(1):65-71
OBJECTIVE: To evaluate feasibility of performing laparoscopic-assisted placement of a jejunostomy feeding tube (J-tube) and compare complications associated with placement, short-term feedings, and medium-term healing with surgically placed tubes in dogs. DESIGN: Prospective study. ANIMALS: 15 healthy mixed-breed dogs. PROCEDURES: Dogs were randomly allocated to undergo open surgical or laparoscopic-assisted J-tube placement. Required nutrients were administered by a combination of enteric and oral feeding while monitoring for complications. Radiographic contrast studies documented tube direction and location, altered motility, or evidence of stricture. RESULTS: Jejunostomy tubes were successfully placed in the correct location and direction in all dogs. In the laparoscopic group, the ileum was initially selected in 2 dogs, 2 dogs developed moderate hemorrhage at a portal site, and 2 J-tubes kinked during placement but were successfully readjusted postoperatively. All dogs tolerated postoperative feedings. All dogs developed minor ostomy site inflammation, and 1 dog developed bile-induced dermatitis at the ostomy site. Despite mild, transient neutrophilia, no significant difference was noted in WBC counts between groups. No dog had altered gastric motility or evidence of stricture, although the jejunopexy site remained identifiable in several dogs at 30 days. CONCLUSIONS AND CLINICAL RELEVANCE: Requirements for successful J-tube placement were met by use of a laparoscopic-assisted technique, and postoperative complications were mild and comparable to those seen with surgical placement. Laparoscopic-assisted J-tube placement compares favorably to surgical placement in healthy dogs and should be considered as an option for dogs requiring enterostomy feeding but not requiring a celiotomy for other reasons. 相似文献
80.
Foster JG Clapham WM Belesky DP Labreveux M Hall MH Sanderson MA 《Journal of agricultural and food chemistry》2006,54(5):1772-1778
The forage potential of chicory (Cichorium intybus L.) has not been realized in southern West Virginia (WV) because ruminants are reluctant to consume the herbage. Chicory contains bitter sesquiterpene lactones that can adversely impact palatability. This study was undertaken to determine whether sesquiterpene lactone concentrations in chicory grown in southern WV differ from those in chicory grown in central Pennsylvania (PA) where chicory is grazed readily. Herbage was collected in 1997 and 1998 from cultivars Grasslands Puna (Puna), INIA le Lacerta (Lacerta), and Forage Feast established at research sites near State College, PA, and Beckley, WV. The total concentration of sesquiterpene lactones in WV-grown cultivars was 0.58% (dry matter basis) in Puna, 0.59% in Lacerta, and 0.79% in Forage Feast in 1997 and ranged from 1.03 (Lacerta) to 1.52% (Forage Feast) in 1998. In PA-grown cultivars, sesquiterpene lactones represented 0.16 (Puna), 0.18 (Lacerta), and 0.27% (Forage Feast) of the forage dry matter in 1997 and ranged from 0.32 (Lacerta) to 0.55% (Forage Feast) in 1998. Concentrations of lactucin, lactucopicrin, and total sesquiterpene lactones in Forage Feast exceeded those in the other cultivars grown at the same site. The lowest concentrations of lactucopicrin and total sesquiterpene lactones observed among WV-grown cultivars were higher (2-fold or more) than the highest concentrations present in cultivars grown the same year in PA. Mineral analyses of soils from the two cultivation sites indicate that P availability may influence sesquiterpene lactone composition of chicory herbage. Results provide a foundation for future studies of environmental effects on sesquiterpene lactone composition and palatability of chicory herbage. 相似文献