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111.
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   
112.
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   
113.
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   
114.
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   
115.
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117.
A total of 578 slaughter pigs from 2 Danish conventional farrow-to-finish operations (Herds A and B) were followed from an age of 14 days to slaughter. Pigs were weighed at 3 weeks intervals and at slaughter and an extended post mortem examination of the plucks was done. Comparison of growth rates in pigs with and without specific types of lesions by the t-test and those with multiple lesions with regression models demonstrated that Mycoplasma-like pneumonia, complicated pneumonia, anterio-ventral pleuritis, fissures and atrophic rhinitis significantly reduced mean daily gain and increased the time required to reach slaughter weight. The total impact of the lesions in Herd A was an estimated reduction in mean daily gain of 27 grams and a 2 day increase in the interval from 14 days of age until slaughter (MDG14). Decreases in MDG14 in Herd B were more substantial, 98 grams and 16.7 days. Reductions in mean daily gains during the interval from the fourth weighing until slaughter were 31 grams in Herd A and 137 grams in Herd B. Chronic dorso-caudal and parietal pleuritis, without other lesions present, had no significant adverse effects on growth rates in either herd. Interactions between lesions did not significantly alter the estimates. The R2 values obtained for the regression models showed that the presence, absence or extent of lesions at slaughter explained only 13-27% of the variations in growth rates in the 2 herds.  相似文献   
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119.
The transformation of recent igneous rock occurs with participation of microorganisms associated with the deposition of iron and aluminum on their cell surface. An identity of morphological structures was found in the microorganisms in both cases, and this fact counts in favor of their similarity and wide distribution in the rock being transformed. The polymorphous acid-resisting organism identified by our studies was tentatively classified with the Metallogenium-Siderococcus group.  相似文献   
120.
Distribution patterns of calcium in peat deposits of seventeen bogs in the middle and southern taiga of Western Siberia have been studied. Four types of Ca distribution patterns related to the genesis of peat deposits are specified. Up to three Ca-enriched peat layers are distinguished in thick deposits. This Ca distribution pattern is typical of different peat deposits formed under various conditions. It is shown that Ca accumulation in particular layers of peat deposits is related to the warm stages of the Holocene.  相似文献   
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