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61.
The aim of this study was to investigate to what extent different occupational devices (pendular beam, cross of chains or lifting beam) offered simultaneously were used by one or more pigs kept in pens with or without straw during the fattening period. The data were obtained in four fattening periods. In every round four pens with nine animals each were available, two of them had a solid concrete floor and were littered with straw the other two had a partially slatted floor without any straw. At three stages during each fattening period the behaviour of the pigs was video-recorded for 24 h and their use of each occupational tool was analysed second-wise.In both housing systems the cross of chains was used longer for occupation than the other devices. The pendular beam was used least of all. All three devices could have been used by more than one pig at the same time, but the cross of chains was used longer by two to four pigs simultaneously than the others. It was observed that pigs in pens without straw used the cross of chains and the lifting beam significantly (p < 0.05) longer than the pigs in the pens with straw.All three devices are suitable to enrich a housing system without any litter. Especially a cross of chains allows the pigs to perform their explorational behaviour.  相似文献   
62.
Clostridium (C.) difficile is a common cause of nosocomial diarrhea in horses. Vancomycin and metronidazole have been used as standard treatments but are only moderately effective, which highlights the need for a novel alternative therapy. In the current study, we prepared antiserum of equine origin against both C. difficile toxins A and B as well as whole-cell bacteria. The toxin-neutralizing activities of the antibodies were evaluated in vitro and the prophylactic effects of in vivo passive immunotherapy were demonstrated using a conventional mouse model. The data demonstrated that immunized horses generated antibodies against both toxins A and B that possessed toxin-neutralizing activity. Additionally, mice treated with the antiserum lost less weight without any sign of illness and regained weight back to a normal range more rapidly compared to the control group when challenged orally with 107 C. difficile spores 1 day after serum injection. These results indicate that intravenous delivery of hyperimmune serum can protect animals from C. difficile challenge in a dose-dependent manner. Hence, immunotherapy may be a promising prophylactic strategy for preventing C. difficile infection in horses.  相似文献   
63.
In the recent past, pig performance and sow management on smallholder farms in the Southeast Asian Massif have been extensively researched. But the objective of this study was to investigate the lifetime efficiency of breeding sows of the local Vietnamese Ban (n = 89) and Mong Cai (n = 131) breeds in a production system context. The impact of sow longevity was considered in particular. In addition, predictors of early pre-weaning mortality in piglets were investigated. In total, nine villages of Son La province, situated in the uplands of north-western Vietnam, were selected, differing in access to markets, production intensity, and pig management level. Data was collected over a period of 10 years through an on-farm performance testing system. It was shown that sows of both breeds that achieved five or more parities farrowed and weaned significantly more piglets per life year compared to sows with only one or two parities. The conception rate (Spearman’s rho = 0.374) and age at first farrowing (Spearman’s rho = ?0.424) were significantly correlated with the number of weaned piglets per life year of stayable (≥4 parities) Mong Cai sows. The risk of early pre-weaning death of piglets born to Mong Cai sows was affected more by litter size, while for piglets born to Ban sows, the risk was influenced more by the season. Therefore, interventions to improve the sow lifetime efficiency and piglet survivability must match the sow breed and management level.  相似文献   
64.
OBJECTIVE: To evaluate the use of xylazine and ketamine for total i.v. anesthesia in horses. ANIMALS: 8 horses. PROCEDURE: Anesthetic induction was performed on 4 occasions in each horse with xylazine (0.75 mg/kg, i.v.), guaifenesin (75 mg/kg, i.v.), and ketamine (2 mg/kg, i.v.). Intravenous infusions of xylazine and ketamine were then started by use of 1 of 6 treatments as follows for which 35, 90, 120, and 150 represent infusion dosages (microg/kg/min) and X and K represent xylazine and ketamine, respectively: X35 + K90 with 100% inspired oxygen (O2), X35 + K120-(O2), X35 + K150-(O2), X70 + K90-(O2), K150-(O2), and X35 + K120 with a 21% fraction of inspired oxygen (ie, air). Cardiopulmonary measurements were performed. Response to a noxious electrical stimulus was observed at 20, 40, and 60 minutes after induction. Times to achieve sternal recumbency and standing were recorded. Quality of sedation, induction, and recovery to sternal recumbency and standing were subjectively evaluated. RESULTS: Heart rate and cardiac index were higher and total peripheral resistance lower in K150-(O2) and X35 + K120-air groups. The mean arterial pressure was highest in the X35 + K120-air group and lowest in the K150-(O2) group (125 +/- 6 vs 85 +/- 8 at 20 minutes, respectively). Mean Pa(O2) was lowest in the X35 + K120-air group. Times to sternal recumbency and standing were shortest for horses receiving K150-(O2) (23 +/- 6 minutes and 33 +/- 8 minutes, respectively) and longest for those receiving X70 + K90-(O2) (58 +/- 28 minutes and 69 +/- 27 minutes, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Infusions of xylazine and ketamine may be used with oxygen supplementation to maintain 60 minutes of anesthesia in healthy adult horses.  相似文献   
65.
OBJECTIVE: To analyse factors associated with breast-feeding and use of sweetened drinks at 12 months, and to compare dietary habits among breast-fed and non-breast-fed infants. DESIGN: Data were collected by a semi-quantitative food-frequency questionnaire filled in by the parents. SETTING: National dietary survey in Norway. SUBJECTS: In total, 1932 12-month-old infants were included. RESULTS: At 12 months, 36% of the infants were breast-fed. The odds of breast-feeding at this age were more than doubled both for mothers > or =35 years compared with mothers <25 years and for mothers in the highest educational group compared with mothers in the lowest. A negative association was found for maternal smoking, and the odds of breast-feeding were 40% lower for mothers who smoked than for non-smokers. Some dietary differences were observed between breast-fed and non-breast-fed infants apart from intake of milk. In particular, breast-fed infants had a significantly lower daily intake of sweetened drinks than non-breast-fed infants and a 16% lower mean daily intake of added sugars (P<0.001). Furthermore, breast-fed infants had 30% higher odds of not receiving sweetened drinks daily, compared with non-breast-fed infants. CONCLUSIONS: Maternal age, education and smoking status were important factors for breast-feeding at 12 months. Breast-fed infants had lower intakes of sweetened drinks and added sugars than non-breast-fed infants. From a public health perspective, continued promotion of breast-feeding is needed to reduce inequalities in breast-feeding. Moreover, prevention of high intakes of sweetened drinks and added sugars should start in infancy.  相似文献   
66.
67.
Antigenic and genetic analysis of the hemagglutinin of approximately 13,000 human influenza A (H3N2) viruses from six continents during 2002-2007 revealed that there was continuous circulation in east and Southeast Asia (E-SE Asia) via a region-wide network of temporally overlapping epidemics and that epidemics in the temperate regions were seeded from this network each year. Seed strains generally first reached Oceania, North America, and Europe, and later South America. This evidence suggests that once A (H3N2) viruses leave E-SE Asia, they are unlikely to contribute to long-term viral evolution. If the trends observed during this period are an accurate representation of overall patterns of spread, then the antigenic characteristics of A (H3N2) viruses outside E-SE Asia may be forecast each year based on surveillance within E-SE Asia, with consequent improvements to vaccine strain selection.  相似文献   
68.
The fungus Fusarium graminearum (sexual stage Gibberella zeae) causes ear rot of maize (Zea mays) and contamination with the 8-ketotrichothecenes nivalenol (1) or 4-deoxynivalenol (2), depending on diversity of the fungal population for the 4-oxygenase gene (TRI13). To determine the importance of 1 and 2 in maize ear rot, a survey of naturally contaminated maize in Nepal was combined with experiments in the field and in a plant growth room. In the survey, 1 contamination was 4-fold more frequent than 2 contamination and 1-producers (TRI13) were isolated more than twice as frequently as 2-producers (Psi TRI13). In maize ear rot experiments, genetically diverse 1-producers and 2-producers caused ear rot and trichothecene contamination. Among strains with the same genetic background, however, 1-producers caused less ear rot and trichothecene contamination than did 2-producers. The high frequency of 1 contamination and the high virulence of many 1-producers are of concern because maize is a staple food of rural populations in Nepal and because 1 has proven to be more toxic than 2 to animals.  相似文献   
69.
铺装是庭院里最实用的元素之一,若是能在铺装中注入设计元素,您的庭院将会别具一格。  相似文献   
70.
Conservation biological control avoids the need for mass releases of costly agents and the risks associated with introducing exotic agents by promoting existing natural enemies. This is done by alleviating insecticide-induced mortality and by manipulating the habitat to provide resources such as nectar, but there is a dearth of information on the relative and interactive effects of these two approaches. Here we used a large-scale factorial experiment with plots comprised of entire fields to test the effects of, and interactions between, withholding insecticides and planting borders of sesame (Sesamum indicum) on natural enemies and pests over 2 years. We used yellow sticky traps, sweeping netting and sentinel bait plants to monitor natural enemies and pests in the canopy and basal zones of the rice crop. Numbers of rice planthopper egg parasitoids and lepidopterous egg parasitoids in the rice canopy, as well as planthopper parasitism rates, were significantly greater in plots that were unsprayed and bordered by sesame, and scarcest in sprayed crops without sesame. Spraying of sesame-bordered crops gave parasitoid numbers similar to sprayed crops without sesame. Spiders in the canopy were significantly reduced in numbers by spraying, but there was no main effect of sesame borders. This study demonstrates that withholding insecticides and sowing nectar plant borders each have measurable as well as additive benefits on in-crop densities of ecosystem service providers responsible for predating and parasitising pests but the identity of the natural enemy determines the impact of these management practices.  相似文献   
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