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231.
J K House M M Ontiveros N M Blackmer E L Dueger J B Fitchhorn G R McArthur B P Smith 《American journal of veterinary research》2001,62(12):1897-1902
OBJECTIVE: To compare the efficacy of a Salmonella bacterin and a modified live Salmonella ser. Choleraesuis vaccine on a commercial dairy. ANIMALS: 450 cows in late gestation and 80 calves. PROCEDURE: Group-1 cows (n = 150) were vaccinated once with a modified live S. Choleraesuis (serogroup C1) strain 54 (SC54) vaccine, group-2 cows (150) were vaccinated on enrollment and 30 days later with a Salmonella ser. Montevideo (serogroup C1) bacterin, and group-3 cows (150) served as unvaccinated controls. One gallon of colostrum harvested from the first 80 cows to calve was fed to each calf. Outcome assessments included fecal shedding of Salmonella spp for the first 10 days after parturition (cows) or birth (calves), milk production, involuntary culling rate, mastitis incidence, antimicrobial use, and mortality rate. RESULTS: Salmonellae were isolated from 306 of 309 (99%) cows and 64 of 74 (86.5%) calves. Shedding frequency was less in SC54-vaccinated cows and calves that received colostrum from those cows, compared with the other groups, and vaccination was specifically associated with less shedding of serogroup C1 salmonellae. Production data were similar among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Vaccination of pregnant cows with an autogenous Salmonella bacterin had no effect on fecal shedding of salmonellae, whereas vaccination with a modified live S. Choleraesuis vaccine reduced the frequency of fecal shedding of serogroup C1 salmonellae during the peripartum period. A commercial S. Choleraesuis vaccine licensed for use in swine may be more efficacious than autogenous Salmonella bacterins on dairies infected with serogroup C1 salmonellae. 相似文献
232.
S E Heath S K Voeks L T Glickman 《Journal of the American Veterinary Medical Association》2001,218(12):1898-1904
OBJECTIVE: To describe epidemiologic features of pet evacuation failure after a hazardous chemical spill in which residents had no warning and only a few hours notice to evacuate. DESIGN: Cross-sectional study. SAMPLE POPULATION: Pet-owning households that evacuated from a hazardous chemical spill with (n = 119) or without (122) their pets. Procedures-Evacuees were surveyed by mail. RESULTS: 261 of 433 (60.3%) dogs and cats in 241 households were not evacuated. Of the 241 households, 119 (49.4%) evacuated with their pets, 98 (40.7%) evacuated without them but later attempted to rescue them, and 24 (10.0%) neither evacuated their pets nor attempted to rescue them. Pet evacuation failure was most common in households that thought the evacuated area was safe for pets. Risk of pet evacuation failure increased in households with many animals, low pet attachment and commitment scores, and low levels of preparedness. Cat evacuation failure was associated with not having cat carriers. Nearly 80% of households that evacuated with their pets found accommodation with friends and family. CONCLUSIONS AND CLINICAL RELEVANCE: Pet evacuation failure was common and jeopardized pets' health and well-being. Logistical challenges to transporting pets were substantial contributors to pet evacuation failure, whereas not knowing where to house a pet was only a minor concern. Most pet owners seemed self-reliant and acted appropriately towards their pets. Such self-reliant behavior by pet owners should be encouraged prior to disasters as part of an evacuation plan for households. 相似文献
233.
S E Heath A M Beck P H Kass L T Glickman 《Journal of the American Veterinary Medical Association》2001,218(12):1905-1910
OBJECTIVE: To determine risk factors for pet evacuation failure during a flood. DESIGN: Cross-sectional survey. SAMPLE POPULATION: 203 pet-owning households in a flooded region. PROCEDURES: Persons under evacuation notice because of a flood were interviewed by use of a random telephone survey. RESULTS: 102 households evacuated with their pets, whereas 101 households evacuated without their pets. Low pet attachment and commitment scores were significantly associated with a greater chance of pet evacuation failure. Risk of pet evacuation failure and lower attachment and commitment scores were also associated with pet management practices prior to the disaster, such as dogs being kept outdoors most of the time or owners not having carriers for their cats. More than 90% of owners made housing arrangements for their pets without assistance. CONCLUSIONS AND CLINICAL RELEVANCE: Predictors of pet evacuation failure are usually present before a disaster strikes and are potentially modifiable. Mitigation of pet evacuation failure should focus on activities that reinforce responsible pet ownership and strengthen the human-animal bond, including socializing dogs, attending dog behavior training classes, transporting cats in nondisaster times, and seeking regular preventive veterinary care. Most pet owners are self-reliant in disasters, and this behavior should be encouraged. 相似文献
234.
A stripspawning methodology was evaluated for tilapia (oreochromid) species. This technique achieved an average hatching success of 68.6 ± 3.6% (N= 31). Female fecundity and spawning frequency were dependant on both genetical and husbandry factors. Egg yields for Oreochromis niloticus, O. mossambicus, and O. niloticus±O. mossambicus hybrids averaged 4.54, 10.86 and 10.36 eggs/g female/spawn, respectively. Female broodstock that were adapted to an intensive spawning regime exhibited a significant increase in fecundity. Additionally, egg survival was not affected by hydration for up to 15 minutes prior to fertilization. Results suggest that the strip spawning of tilapia species may be an efficient method of providing viable gametes for hatchery purposes. 相似文献
235.
Y. SANTOS I. BANDIN S. NUÑEZ K. GRAVNINGEN A. E. TORANZO 《Journal of fish diseases》1991,14(3):407-411
Abstact. The potency of a whole-cell bacterin (WCB) and a toxoid enriched whole-cell vaccine (WCEB) administered intraperitoncally into rainbow trout, Oncorhynchus mykiss (Richardson), were compared. The most effective vaccine was further evaluated by bathing turbot, Scophthalmus maximus (L.). These vaccines were composed of three strains of V. anguillarun , of the serotypes 01 and 02. Both vaccines conferred the highest protection against strains of serotype 01 within 4 weeks. With the toxoid enriched vaccine giving the best results (77 RPS). When trout were revaccinated after 7 weeks with this vaccine, good protection was achieved against strains of serotypes 01 and 02. Interestingly, when the WCEB was administered by bath to turbot, acceptable levels of protection against strains of both serotypes were obtained after 4 weeks of immunization. 相似文献
236.
237.
238.
Polysaccharide-induced protection of carp, Cyprinus carpio L., against bacterial infection 总被引:5,自引:0,他引:5
Abstract. The efficacy of 10 polysaccharides (curdlan, inulin, krestin, laminaran, lentinan, levan, schizophylian, selerogiucan, yeast glucan and zymosan) to enhance protection of carp, Cyprinus carpio L., against bacterial infection was investigated. Carp were intraperitoneally injected with the polysaceharides (2–l0 mgkg-1 ) on days 1 and 4, and challenged with Edwardsiella tarda on day 7. Among the polysaccharides tested, lentinan, schizophyllan and scleroglucan, which are l,6-branchcd-β-l,3-glucans, significantly increased the survival rate. They also induced a protective effect against Aeromonas hydrophila at a dose of 5 mg kg-1 . The ability of the polysaccharides to activate the alternative complement pathway (ACP) was examined by incubating the polysaccharides with carp serum and measuring the residual ACP activity. At a final concentration of 0.l mgml-1 , l,6-branched-β-1,3-glucans greatly reduced (76–77%) the ACP activity. Therefore, it is suggested that the protective effect of the l,6-branched-β-1,3-glucans may be associated with the activation of ACP. 相似文献
239.
Zheng Xiaoxian Liu Donglan College of Forest Resources Environment Beijing Forestry University Beijing P.R.China 《中国林学(英文版)》1996,(1)
该文探讨了不用编制削度表直接建立高精度立木干曲线的方法.当采用干曲线是3次多项式时,通常根据10分法测定树干各部位直径,用最小二乘法求出该方程式的参数.从数学角度,只要知道树干任意3个部位的直径,就可以用最小二乘法或联立方程式求解干曲线参数.本文以樟子松为例,探讨用树干哪3个部位直径拟合的干曲线最接近实际干曲线,为建立立木干曲线提供有效方法.利用9个部位半径(方法Ⅰ)和利用其中3个部位半径(方法Ⅱ,28种组合)分别拟合干曲线,结果表明方法Ⅱ的6种半径组合的精度良好,其中的3种组合,(r1.3,r0.3,r0.7),(r1.3,r0.4,r0.7)和(r1.3,r0.4,r0.8)是拟合现实干曲线的有效方法. 相似文献
240.
Lack of effect of recombinant bovine interferon alpha I1 in the treatment of experimentally-induced bovine warts.
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Fifteen four-month old calves were inoculated, on five scarified sites on each side of the neck, with a suspension of ground wart tissue from a steer naturally infected with bovine papilloma virus 1. Warts started to appear about one month postinfection and were measurable in ten calves two months postinfection, when the trial started. After stratification on the size of the warts, all fifteen calves were allocated randomly to one of the following treatment groups: twice weekly intramuscular injections of 5 mg recombinant bovine interferon alpha I1 (rBoIFN alpha I1), weekly injection of 5 mg of rBoIFN alpha I1 or placebo, for three weeks. The biggest wart on each calf at the beginning of the trial was measured and photographs of all warts were taken weekly for five weeks. An analysis of covariance on the log of the volumes of warts during the five weeks of the trial showed a significant difference between groups (p = 0.026). Warts in treated groups tended to grow faster than in the placebo group. 相似文献