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991.
Ontario initiated a red fox (Vulpes vulpes ) oral rabies vaccination (ORV) programme in 1989. This study utilized a benefit‐cost analysis to determine if this ORV programme was economically worthwhile. Between 1979 and 1989, prior to ORV baiting, the average annual human post‐exposure treatments, positive red fox rabies diagnostic tests and indemnity payments for livestock lost to rabies were 2248, 1861 and $246 809, respectively. After baiting, from 1990 to 2000, a 35%, 66% and 41% decrease in post‐exposure treatments, animal rabies tests and indemnity payments was observed, respectively. These reductions were viewed as benefits of the ORV programme, whereas total costs were those associated with ORV baiting. Multiple techniques were used to estimate four different benefit streams and the total estimated benefits ranged from $35 486 316 to $98 413 217. The annual mean ORV programme cost was $6 447 720, with total programme costs of $77 372 637. The average benefit‐cost ratios over the analysis period were .49, 1.06, 1.27 and 1.36, indicating overall programme efficiency in three of the four conservative scenarios.  相似文献   
992.
Tick‐borne encephalitis virus (TBEV) is the aetiological agent of tick‐borne encephalitis (TBE), a potentially fatal central nervous system infection of humans. TBE is endemic in many areas of Europe and Asia; however, very scarce data on TBEV activity are available from Turkey. We aimed to identify TBEV exposure in healthy blood donors and the impact of TBEV in central nervous system infections in Central/Northern Anatolia. Two‐thousand four hundred and fifty four sera, collected from blood donors at Ankara, Konya, Eski?ehir and Zonguldak branches of the Turkish Red Crescent Middle Anatolia Regional Blood Center, were analysed for TBEV serosurveillance. Paired serum and cerebrospinal fluid samples from 108 patients with the diagnosis of aseptic meningitis/encephalitis of unknown aetiology were also evaluated to identify TBE and neuroborreliosis cases. Commercial enzyme‐linked immunosorbent assays and indirect immunofluorescence tests were employed for antibody detection. Forty‐seven donor samples (1.9%) were reactive for TBEV IgG. In 25 persons with IgG reactivity (53.1%), risk factors for tick‐borne infections were revealed. One sample from Zonguldak province (1/198; 0.5%) in the Black Sea region of Turkey was confirmed to possess neutralizing antibodies via plaque reduction neutralization test. TBEV IgM was detected in 9.2% (8/108) of the patients. IgM was accompanied by IgG reactivity in two persons where, in one, recent history of a tick bite was also identified. Intrathecal antibody production for TBEV could not be demonstrated. No evidence for Borrelia infections could be found. Confirmed exposure to TBEV and/or an antigenically similar tick‐borne flavivirus is documented for the first time in blood donors in Zonguldak in Northern Anatolia. Probable cases of TBE have also been identified from Central Anatolia. The epidemiology of TBEV activity in Turkey needs to be assessed and benefits of vaccination for general population, risk groups or travellers must be considered.  相似文献   
993.
This trial was conducted to evaluate if the effect of condensed tannin (CT) is associated with a true protein source on intake, ruminal and total digestibility, ruminal digestion rate, protein efficiency, and microbial efficiency in beef steers fed high concentrate diet (87% of DM). Four Bos indicus steers (407 ± 12 kg of BW) fitted with rumen cannula were assigned to a 4 × 4 Latin square design, arranged in a 2 × 2 factorial arrangement. Treatments consisted of either inclusion (0.4% of DM) or exclusion of condensed tannin (CT) from quebracho extract (76% of CT) with or without the use of soybean meal (SBM) as source of true protein. The level of inclusion was calculated to provide a daily intake of 1 g/10 kg of BW of CT. Intake of DM and nutrients was not affected (P > 0.10) by CT inclusion. However, there was an effect (P < 0.10) of CT inclusion on ether extract digestibility. An interaction (P < 0.10) was observed between CT and SBM on ruminal digestibility and digestion rate of crude protein (CP): when mixed with soybean meal, CT decreased the ruminal digestibility and, consequently, reduced the digestion rate of CP. Intake of CP increased (P < 0.10) with the inclusion of SBM. No differences in DM passage rate were observed (P > 0.10) among treatments. Effects of the interaction (P < 0.10) between CT and SBM were observed on flux of rumen undegradable protein (RUP), metabolizable protein (MP), and on the ratio MP:CP. In the presence of soybean meal, the addition of CT increased (P < 0.10) the flux of RUP and MP, and improved the ratio MP:CP. The yield of microbial protein on the abomasum and the microbial efficiency did not differ among treatments (P > 0.10). There was no difference (P > 0.10) on the pH, VFA, and ruminal ammonia (N-NH3) with the addition of condensed tannin. The N-NH3 increased and the ruminal pH decreased with the inclusion of soybean meal (P < 0.10). The utilization of condensed tannin as an additive in beef cattle diets with high level of concentrate and soybean meal as a source of true protein implies positive effects on crude protein utilization, decreasing digestion rate and ruminal digestibility of crude protein and consequently increasing the levels of metabolizable protein, with no changes in the ruminal fermentation parameters.  相似文献   
994.
To examine the effect of a modification of a typically Irish dairy calf-to-beef production system, Charolais × Friesian steers were offered a finishing ration of grass silage ad libitum and 5.6 kg concentrates daily for 174 days prior to slaughter at 25 months of age or grass silage ad libitum for 174 days, followed by pasture for 167 days and slaughter at 30 months of age. Finishing at pasture increased carcass weight (376 vs. 342 kg) but did not affect intra-muscular lipid concentration (28 vs. 24 g/kg). Finishing at pasture decreased Longissimus thoracis et lumborum lightness (35.6 vs. 36.9) and increased shear force of muscle at 2 (8.54 vs 4.32) and 7 days (5.21 vs 3.64 kg) post-mortem but not at 14 days post-mortem (4.45 vs. 3.42 kg). Finishing at pasture did not affect the sensory characteristics of tenderness, juiciness, firmness or chewiness and tended (P < 0.1) to decrease texture and acceptability. It is concluded that modification of this beef production system as described, had minor effects on beef quality which are unlikely to be of commercial significance.  相似文献   
995.
From 2012 onwards, housing of laying hens in conventional battery cages will be forbidden in the European Union and only enriched cages and non‐cage housing systems such as aviaries, floor‐raised, free‐range and organic systems will be allowed. Although this ban aims at improving the welfare of laying hens, it has also initiated the question whether there are any adverse consequences of this decision, especially with respect to the spread and/or persistence of zoonotic agents in a flock. A zoonotic agent that is traditionally associated with the consumption of eggs and egg products is Salmonella enteritidis. This paper provides a summary of the current knowledge regarding the direct and indirect effects of different housing systems on the occurrence and epidemiology of Salmonella in laying hen flocks.  相似文献   
996.
Hypothesis/ObjectivesTo describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications.Animals, materials and methodsOne hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits.ResultsAll cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1–870).ConclusionPimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats.  相似文献   
997.
Discrimination between nestmates and non‐nestmates in social insects is thought to rely on the pattern of cuticular hydrocarbons. We investigated the cuticular hydrocarbon profiles of 2 parapatric sibling ant species, Temnothorax nylanderi (Förster, 1850) and Temnothorax crassispinus (Karavaiev, 1926), and their hybrid. We found that although the profiles show considerable similarities, a discriminant analysis based on the relative peak areas of cuticular hydrocarbons separates the 3 taxa. The profiles of hybrids were not consistently intermediate between those of the paternal species, suggesting either non‐additive interactions among the parental biosynthetic pathways or systematic differences in environment‐derived odor cues.  相似文献   
998.
Fleshy‐fruited plants in tropical forests largely rely on vertebrate frugivores to disperse their seeds. Although this plant–animal interaction is typically considered a diffuse mutualism, it is fundamental as it provides the template on which tropical forest communities are structured. We applied a mutualistic network approach to investigate the relationship between small‐fruited fleshy plant species and the fruit‐eating bird community in an intact evergreen forest in northeast Thailand. A minimum of 53 bird species consumed fruits of 136 plant species. Plant‐avian frugivore networks were highly asymmetrical, with observed networks filling 30% of all potential links. Whereas some of the missing links in the present study might be due to undersampling, forbidden links can be attributed to size constraints, accessibility and phenological uncoupling, and although the majority of missing links were unknown (58.2%), many were probably due to a given bird species being either rare or only a very occasional fruit eater. The most common frugivores were bulbuls, barbets and fairy‐bluebirds, which were responsible for the majority of fruit removal from small fleshy fruited species in our system. Migratory birds seemed to be a minor component of the plant‐frugivore networks, accounting for only 3% of feeding visits to fruiting trees; they filled 2% of the overall potential networks. The majority of interactions were generalized unspecific; however, Saurauia roxburghii Wall. appeared to be dependent on flowerpeckers for dispersal, while Thick‐billed Pigeons were only seen to eat figs.  相似文献   
999.
Banana is an increasingly demanded food and cash crop in sub-Saharan Africa. Reported yields in smallholder farms vary substantially. The importance and spread of yield constraints have not been properly quantified. A study was carried out in Central Kenya to (i) quantify the yield levels, the primary yield constraints, and the spatial production gradients in such systems (ii) explore how soil fertility gradients relate to gradients in soil fertility management, and whether this is a function of farmer resource availability. Data was collected on crop management aspects, pests and diseases, and soil and plant tissue samples analyzed for nutrient contents. Bunch yields were higher near homesteads (29.8 t ha−1 yr−1) than at mid-distance (26.8 t ha−1 yr−1), or far away 20.2 t ha−1 yr−1. Yields were much higher than previously reported (11–14 t ha−1 yr−1) in Kenya. Both soil and tissue K levels were higher near and mid-distance, than far from the homestead. Gradients of soil pH, total N, available P and Organic carbon were found, being higher near the homestead, while Mg and Ca were lowest near the homesteads. K was the most deficient nutrient, with tissue K index (IK) decreasing when moving away from the homesteads. P and Ca deficiencies were also observed. Resource-poor farmers’ soils were higher in exchangeable K and Mg, pH, and total N, and supported higher mat densities compared to resource-endowed farmers’ farms. Soil quality problems were the biggest yield loss factors and not pests and diseases.  相似文献   
1000.
The effect of girdling on abscisic acid, carotenoids content, xanthophylls cycle and non-photoquemical quenching was studied in leaves from different shoot types of containerized two-year-old ‘Loretina’ mandarin during spring flush period. Girdling increased abscisic acid in young leaves and decreased it in mature leaves. These changes were accompanied by a significant increase in leaf carotenoids, carotenoids:chlorophylls ratio, xanthophylls and xanthophylls cycle pool size and its de-epoxidation state in vegetative and multiflowered young leafy shoots. However, changes in de-epoxidation state did not correlate with the energy-dependent non-photochemical quenching. The role of carotenoids and abscisic acid as photoprotecting agents during the oxidative stress caused by girdling is discussed. In conclusion, this study provides evidence linking carotenoids-based photoprotecting mechanisms in the response to the stress induced by girdling in Citrus trees.  相似文献   
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