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71.
Objective: To provide information on the ingestion, and subsequent toxicity, of raw bread dough in dogs. Case summary: A report from the ASPCA animal poison control center (APCC) files of 3 cases of ingestion of raw bread dough by dogs. Clinical signs included vomiting, ataxia, blindness, hypothermia, and recumbency. All dogs were successfully treated for ethanol toxicosis. New information: Ingestion of bread dough can cause gastric obstruction, bloat, or ethanol toxicosis. The treatment of ethanol toxicosis, including decontamination, IV fluids, management of metabolic acidosis, and hypoglycemia is discussed. Yohimbine can be used in cases where the dog is comatose or has developed severe respiratory depression.  相似文献   
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To obtain information both about the prevalence of Giardia and Cryptosporidium in Danish cattle and pigs as well as the possible influence of different management systems on the occurrence and intensity of infection, we conducted an epidemiological survey comprising 50 randomly selected dairy and sow herds, respectively. Each herd was visited once for the collection of faecal samples and registration of basic management parameters. Faecal samples were collected from three different age groups of animals, i.e. 5 sows/cows, 10 nursing piglets/calves less than 1 month, and 10 weaner pigs 8-45 kg/calves 1-12 months. The faecal samples were purified and the number of (oo)cysts quantified. The study revealed an age-specific herd prevalence of Cryptosporidium of 16, 31 and 100% for sows, piglets and weaners, respectively, and of 14, 96 and 84% for cows, young calves and older calves, respectively. For Giardia the age-specific herd prevalence was 18, 22 and 84% for the sows, piglets and weaners, while for cattle herds the prevalence was 60, 82 and 100% for cows, young calves and older calves, correspondingly. The (oo)cyst excretion levels varied considerably both within and between herds for all age groups. Risk factors were evaluated by using proportional odds models with (oo)cyst excretion levels divided into four categories as response. Among the numerous risk factors examined, only a few were demonstrated to have a statistically significant influence, e.g. the use of an empty period in the calf pen between introduction of calves for both parasites had a protective effect in young calves. For weaners, use of straw in the pen and high pressure cleaning between batches of weaners had a preventive effect against higher Cryptosporidium oocyst excretion levels.  相似文献   
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Background

Measurement of salivary cortisol has been used extensively as a non-invasive alternative to blood sampling to assess adrenal activity in ruminants. However, there is evidence suggesting a considerable delay in the transfer of cortisol from plasma into saliva. Previous studies in cattle have used long sampling intervals making it difficult to characterise the relationship between plasma and salivary cortisol (PLCort and SACort, respectively) concentrations at different time points and determine whether or not such a time lag exist in large ruminants. Therefore, the objective of this study was to characterise the relationship between plasma and salivary cortisol and determine if there is a significant time lag between reaching peak cortisol concentrations in plasma and saliva across a 4.25 h time-period, using short sampling intervals of 10–15 min, following social separation in dairy cattle.Five cows were separated from their calves at 4 days after calving, and six calves were separated from a group of four peers at 8 weeks of age. Following separation, the animals were moved to an unfamiliar surrounding where they could not see their calves or pen mates. The animals were catheterised with indwelling jugular catheters 1 day before sampling. Blood and saliva samples were obtained simultaneously before and after separation.

Results

In response to the stressors, PLCort and SACort increased reaching peak concentrations 10 and 20 min after separation, respectively. This suggested a 10 min time lag between peak cortisol concentrations in plasma and saliva, which was further confirmed with a time-series analysis. Considering the 10 min time lag, SACort was strongly correlated with PLCort (P < 0.0001).

Conclusions

Salivary cortisol correlates well with plasma cortisol and is a good indicator of the time-dependent variations in cortisol concentrations in plasma following acute stress. However, there is a time lag to reach peak cortisol concentrations in saliva compared to those in plasma, which should be considered when saliva samples are used as the only measure of hypothalamic-pituitary-adrenal axis response to stress in cattle.  相似文献   
75.
    
  1. Mediterranean freshwater systems are under threat owing to increased drought driven by climate change, intensive human land uses and non-native species. This is causing increased fish hybridization in isolated watercourses.
  2. The genetic and morphological characteristics of hybrids of sympatric native and non-native fish species were studied in four streams of the Mediterranean Guadalquivir basin (south-west Spain). Fish morphology was analysed using geometric morphometrics, and molecular determination of parenthood was inferred through one mitochondrial gene (cytb) and one nuclear gene (Beta-actin) for all hybrids and a subset of pure parental specimens.
  3. Molecular analyses confirmed hybrids between the native Squalius alburnoides and non-native Alburnus alburnus in a stream with continuous flow. Haplotype analyses suggested that they originated from backcrossing of hybrid offspring. Intergeneric crosses between native species S. alburnoides and Pseudochondrostoma willkommii, and S. alburnoides and Iberochondrostoma lemmingii were detected in streams under reduced connectivity scenarios.
  4. Morphometrics revealed that hybrid phenotypes were similar to S. alburnoides. In some cases, molecular markers uncovered hybridization events that were neither detected in the field nor by morphometric analyses, potentially supporting a backcrossing/introgression scenario.
  5. Hybridization is likely to be increasing in Mediterranean rivers where S. alburnoides are present owing to increased fragmentation caused by summer drought exacerbated by climate change and human land uses and pressures. This can become a problem for these endemic vulnerable species if genetic diversity is lost, morphological homogenization occurs and hybrids cannot be easily detected in the field.
  6. The potential risks could be addressed by monitoring and eradication of non-native species and segregation from natives. To avoid native–native crosses, habitat quality and desiccation risk could be tackled by improved water quality and riparian reforestation to provide shade and reduce evapotranspiration. This would need increased coordination and intervention between the institutions that share conservation responsibilities in the area.
  相似文献   
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Over-the-wire (OTW) catheter placement is performed frequently in horses. Intravascular loss of a guidewire has been anecdotally reported, but there is limited information regarding the treatment and outcome of horses that have experienced this complication of OTW catheter placement.  相似文献   
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Canopy‐forming macroalgae can construct extensive meadow habitats in tropical seascapes occupied by fishes that span a diversity of taxa, life‐history stages and ecological roles. Our synthesis assessed whether these tropical macroalgal habitats have unique fish assemblages, provide fish nurseries and support local fisheries. We also applied a meta‐analysis of independent surveys across 23 tropical reef locations in 11 countries to examine how macroalgal canopy condition is related to the abundance of macroalgal‐associated fishes. Over 627 fish species were documented in tropical macroalgal meadows, with 218 of these taxa exhibiting higher local abundance within this habitat (cf. nearby coral reef) during at least one life‐history stage. Major overlap (40%–43%) in local fish species richness among macroalgal and seagrass or coral reef habitats suggest macroalgal meadows may provide an important habitat refuge. Moreover, the prominence of juvenile fishes suggests macroalgal meadows facilitate the triphasic life cycle of many fishes occupying diverse tropical seascapes. Correlations between macroalgal canopy structure and juvenile abundance suggests macroalgal habitat condition can influence levels of replenishment in tropical fish populations, including the majority of macroalgal‐associated fishes that are targeted by commercial, subsistence or recreational fisheries. While many macroalgal‐associated fishery species are of minor commercial value, their local importance for food and livelihood security can be substantial (e.g. up to 60% of landings in Kenyan reef fisheries). Given that macroalgal canopy condition can vary substantially with sea temperature, there is a high likelihood that climate change will impact macroalgal‐associated fish and fisheries.  相似文献   
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