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31.
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Effective conservation of exploited species requires an understanding of the motivations experienced by resource users. When use is illegal, it can be particularly difficult to distinguish users from non-users. The attitudes of local people are critical to conservation success, because they interact with social circumstances to determine behaviour. In this study we explore the factors influencing inferred poaching behaviour of the Critically Endangered saiga antelope (Saiga tatarica) in six communities in three countries of the former Soviet Union. We show that local people have a good understanding of the species’ status and positive attitudes towards its conservation, regardless of their household’s inferred poaching status. Poaching is a low prestige occupation, and our analyses suggest that it is carried out by poor, unemployed households who have the means to hunt. These results are consistent for all villages. However we find important regional differences in hunting behaviour, linked to saiga population density and migration patterns, which have implications for the likely effectiveness of different conservation strategies. Community-based interventions are more likely to be appropriate in Russia, where saigas are present year-round and hunting is more subsistence based, than in the strongly seasonal Kazakhstan populations where economies of scale require organised poaching by fewer households. This case study illustrates the complex linkages between attitudes, social circumstances and behaviour in resource user behaviour, and highlights both the consistencies and differences in drivers of poaching between locations at a range of spatial scales.  相似文献   
33.
Bovine coronavirus (BCoV) is one of the main causes of neonatal calf diarrhoea. Several diagnostic assays have been employed to detect the presence of the virus in stool samples from calves. Despite this, the frequency of BCoV infection among Brazilian and even South American cattle herds has yet to be well characterised. This study describes the occurrence of BCoV infection among calves from dairy and beef herds in four Brazilian states. A total of 282 stool samples from 1 to 60-day-old calves were evaluated for the presence of BCoV by a semi-nested (SN) PCR assay. The animals were from herds (n = 23) located in three geographical regions in Brazil (south, southeast, and center-west). The specific BCoV amplicon was detected in 15.6% (44/282) of the faecal specimens examined, of which 95.4% (42/44) were from diarrhoeic and 4.6% (2/44) from asymptomatic calves. The specificity of the SN-PCR amplicons was evaluated by restriction fragment length polymorphism (RFLP) analysis. The results show that the BCoV is widespread, mainly among calves from 16 to 30-days-old (p = 0.0023), and verify the association between BCoV infection and clinical signs of diarrhoea (p = 0.005). These findings emphasise the importance of this virus in enteric infections of Brazilian cattle herds.  相似文献   
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The aim of this experiment was to test on-farm growing after composting the mixture of following legume plants Crotalaria juncea, Cajanus cajan, Mucuna aterrima with the grass Sorghum bicolor. The treatments were compared to commercial growing medium (CGM) and CGM+NPK to produce bedding plants of lettuce, broccoli, kale, and cabbage. The nutrient contents in CGM and CGM+NPK were higher than the values found in the mixture of the legumes plants with the grass. The pH was higher in the growing media from legume plants as well as the electrical conductivity in the combination CroSor and CajSor. The water retention capacity was higher in the treatments MucSor and CGM. The chemical attributes indicated that CroSor, CajSor, MucSor and CGM+NPK were better than CGM. The growing media from the mixture of legume with grass are an affordable alternative to produce bedding plants of lettuce, broccoli, kale and cabbage under organic agriculture system.  相似文献   
36.
The safe recycling of organic wastes such as the nutrients obtained from agriculture activities is a relevant aspect of the “One Health” strategy, a worldwide initiative including all aspects of health care for humans and animals, as well as aspects related to the conservation and development of the environment. It represents an important opportunity to mitigate the potential impact of microbial pathogens likely present in nutrient natural sources, as digestate, when applied to land as fertilizers. The objectives of the current study were to determine the inactivation of enteric microorganisms in swine digestate (effluent and sludge) during storage in anaerobic conditions and at different ambient temperatures of tropical zones (16, 22, and 37 °C). Human adenovirus 2 (HAdV-2), bacteriophage PhiX-174, and Salmonella enterica serovar typhimurium (S. typhimurium) were used as enteric microbial models to determine the minimum storage time required to reduce at least 3log of enteric microorganisms load in both matrices at the mentioned temperatures. The minimum storage time required for S. typhimurium was shorter than those observed for viruses at 37 °C, while reduction of at least 3log for S. typhimurium was observed after just 1 day; 20 and 90 days were needed for similar reductions for HAdV-2 and PhiX-174, respectively. Similar results were also observed at lower temperatures: 30 and 45 days were needed for S. typhimurium at 22 and 16 °C, respectively, but 30 and 90 days were needed at 22 °C for HAdV-2 PhiX-174, respectively, or 90 and 120 days at 16 °C for HAdV-2 PhiX-174, respectively. This is a pioneering study on the evaluation of inactivation of enteric viruses in swine digestate in usual tropical ambient temperatures; it demonstrates that the time for a considerable inactivation is longer than that observed for a enteric microorganisms (S. typhimurium), and shows that the storage of swine digestate at the referred temperatures can be used as a low-cost post-treatment to inactivate enteric microorganisms, allowing a further use as safer fertilizer.  相似文献   
37.

Objective

To investigate whether pulse pressure variation (PPV) can predict fluid responsiveness in healthy dogs during clinical surgery.

Study design

Prospective clinical study.

Animals

Thirty-three isoflurane-anesthetized dogs with arterial hypotension during orthopedic surgery.

Methods

Fluid challenge with lactated Ringer's solution (15 mL kg?1 in 15 minutes) was administered in mechanically ventilated dogs (tidal volume 10 mL kg?1) with hypotension [mean arterial pressure (MAP) < 65 mmHg]. The volume expansion was considered effective if cardiac output (CO; transesophageal Doppler) increased by ≥ 15%. Cardiopulmonary data were analyzed using two-way ANOVA, receiver operating characteristics (ROC) curves and Spearman coefficient; p < 0.05 was considered significant.

Results

Effective volume expansion, mean ± standard deviation 42 ± 4% increase in CO (p < 0.0001) was observed in 76% of the dogs, resulting in a decrease in PPV (p < 0.0001) and increase in MAP (p < 0.0001), central venous pressure (CVP; p = 0.02) and ejection fraction (p < 0.0001) compared with before the fluid challenge. None of these changes occurred when volume expansion resulted in a nonsignificant CO increase of 4 ± 5%. No significant differences were observed in blood gas analysis between responsive and nonresponsive dogs. The increase in CO was correlated with the decrease in PPV (r = ?0.65; p < 0.0001) but absolute values of CO and PPV were not correlated. The PPV performance (ROC curve area: 0.89 ± 0.06, p = 0.0011) was better than that of CVP (ROC curve area: 0.54 ± 0.12) and MAP (ROC curve area: 0.59 ± 0.13) to predict fluid responsiveness. The best cut-off for PPV to distinguish responders and nonresponders was 15% (50% sensitivity and 96% specificity).

Conclusions and clinical relevance

In mechanically ventilated, healthy, isoflurane-anesthetized dogs, PPV predicted fluid responsiveness to volume expansion, and MAP and CVP did not show such applicability.  相似文献   
38.
The aim of this study was to determine whether applying good practices of handling during the pre-weaning period have long-term effects on behavioral and physiological indicators, health status, and average daily gain (ADG) of crossbred Bos taurus × Bos indicus heifer calves. During the pre-weaning period, 98 crossbred of Holstein × Gir heifer calves were allotted into three treatments: (1) good practices of handling + brushing (GPB; n?=?25), (2) good practices of handling (GP; n?=?25), and (3) control (n?=?48). Every 2 months, four evaluation periods (EV1 to EV4) were conducted to record data. Behavioral indicators comprised time to drive (TD), flight speed (FS), flight distance (FD), and composite reactivity score (CRS). Physiological indicators of acute stress during handling comprised respiratory and heart rates. Health status comprised data regarding occurrence of most common diseases (i.e., pneumonia and anaplasmosis). Collected data were analyzed by using a linear mixed model for repeated measures, Tukey’s test, and chi-squared procedures. Treatment influenced (P?<?0.05) TD, FS, and FD but not CRS (P?=?0.78). From EV1 to EV3, the control calves had the lowest TD. The GPB group had lower FS than the control but did not differ from GP. The GPB group had lower FD means than the other two groups in EV2, EV3, and EV4. No differences (P?>?0.05) due to treatment were observed on heart and respiratory rates, ADG, or occurrence of pneumonia and anaplasmosis. It was concluded that adoption of good practices of handling during pre-weaning period may lead to long-term positive effects.  相似文献   
39.
The environment in which the horse is reared affects its ability to maintain thermal balance which is in turn related to thermal characteristics and regulatory physiological mechanisms. In this study a multivariate analysis of physiological traits in relation to heat tolerance in horses was carried out in the Federal District, Brazil. The aim was to test the ability of these analyses to separate groups of animals and determine which physiological traits are most important in the adaptation to heat stress. Forty adult horses (4 to 13 years) were used, ten from each of four different genetic groups (English thoroughbred, Brazilian showjumper, crossbred and Breton). The traits examined included heart and breathing rate, rectal temperature as well as blood parameters. The data underwent multivariate statistical analysis including cluster, discriminate and canonical using Statistical Analysis System - SAS ® procedures CLUSTER, STEPDISC, CANCORR and DISCRIM. The tree diagram showed clear distances between groups studied and canonical analysis was able to separate individuals in groups. The discriminate analysis identified the variables which were most important in separating these groups. The multivariate analysis was able to separate the animals into groups with RR, HR and RT being important in this separation.  相似文献   
40.
This study aims to investigate the effect of breed and slaughter weight on fatty the acid profile of the Longissimus dorsi muscle in lambs. Twenty-four Santa Inês (SI), 24.5 Ile de France × 0.5 Santa Inês (Ile × SI) and 12.5 Texel × 0.5 Santa Inês (Te × SI), slaughtered at different weights (30, 35, 40, and 45 kg), were evaluated. The animals were reared with creep feeding to weaning and were feedlot finished, receiving a diet composed of 30% hay and 70% concentrate. The analyses of fatty acids were carried out on the Longissimus muscle of the 13th rib. The experiment was in a three by four factorial design. The total mean saturated fatty acid level was 44.88%, with 43.30% monounsaturated fats and 1.72% polyunsaturated. The major fatty acids found included oleic (43%), palmitic (22%), and stearic (18%). The concentration of desirable fatty acids varied from 61.56% to 66.78%, with Te × SI (66.78%) having the highest levels (P < 0.05). The slaughter weight affected (P < 0.05) the saturated and unsaturated (both mono and poly) fatty acid profiles. The 35-kg slaughter weight showed the most desirable fatty acid profile. The saturated myristic and stearic fatty acids decreased with an increase in the slaughter weight, but oleic acid increased. In the conditions of the present study, the meat from Santa Ines and Texel × Santa Ines lambs had fatty acid profiles more beneficial for human health due to the higher levels of unsaturated fatty acids.  相似文献   
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