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1.
The Chinese yew (Taxus chinensis) is catalogued as an endangered species in China because of the small size and senescent status of most populations. Its lack of natural regeneration is the most important reason for its endangered status. We investigated the regeneration of an ex‐situ conservation population, which was introduced into the Nanjing Botanical Garden Memorial Sun Yat‐Sen in the 1950s, and evaluated the role of frugivorous birds on the establishment of this regenerating population. Two hundred and thirteen individual yew seedlings and saplings were found on the hillside in 2006, and the nearest seedling was found more than 10 m away from mother trees. The spatial pattern of all seedlings and saplings occurred as a clumped distribution, which is typical for vertebrate‐dispersed plants. Six bird species were seen ingesting whole “fruits” at yew trees in the present study and 745 visits by avian frugivores were recorded. Red‐billed blue magpie (Urocissa erythrorhyncha), Chinese bulbul (Pycnonotus sinensis) and azure‐winged magpie (Cyanopica cyana) were the most frequent visitors over the two years of the study. Comparing the flights of departure and perching habitats of the three main bird species, we inferred that U. erythrorhyncha would be the most important disperser. This regeneration population has had good development over the past 20 or more years; frugivorous birds have removed seeds to the hillside every year until now, and seed germination and seedling growth continue to develop well under natural conditions. We suggest that the conservation system of the Chinese yew should be composed of yews, avian dispersers and habitats for seed germination and seedling growth.  相似文献   

2.
Seed handling by primary frugivores can influence secondary dispersal and/or predation of post‐dispersal seeds by attracting different guilds of ground‐dwelling animals. Many studies have focused on seeds embedded in feces of mammals or birds; however, less is known about how ground‐dwelling animals treat seeds regurgitated by birds (without pulp and not embedded in feces). To compare the effect of differential seed handling by primary dispersers on secondary seed removal of Chinese yew (Taxus chinensis var. mairei), we conducted a series of exclosure experiments to determine the relative impact of animals on the removal of defecated seeds (handled by masked palm civet), regurgitated seeds (handled by birds) and intact fruits. All types of yew seeds were consistently removed at a higher rate by rodents than by ants. Regurgitated seeds had the highest removal percentage and were only removed by rodents. These seeds were probably eaten in situ without being secondarily dispersed. Defecated seeds were removed by both rodents and ants; only ants might act as secondary dispersers of defecated seeds, whereas rodents ate most of them. We inferred that seeds regurgitated by birds were subjected to the highest rates of predation, whereas those dispersed in the feces of masked palm civets probably had a higher likelihood of secondary dispersal. Seeds from feces attracted ants, which were likely to transport seeds and potentially provided a means by which the seeds could escape predation by rodents. Our study highlighted that primary dispersal by birds might not always facilitate secondary dispersal and establishment of plant populations.  相似文献   

3.
A number of plants are capable of producing intoxication of sufficient severity as to cause death within 12 hours of the onset of clinical signs. Those most rapid in their lethal effects are the cyanogenic plants and yew. Nitrate-accumulating plants likewise are capable of causing sudden death with only a brief appearance of signs. Most toxic plants, however, typically either require a longer time for the intoxication to develop and become lethal or sudden death is the exception rather than the rule following ingestion. In these cases, diagnosis of the problem may be facilitated by recognition of arrays of clinical signs that appear. Seven major groups of presenting signs can be distinguished: dyspnea and polypnea, hemorrhage, prominent excessive muscular activity, depression and/or weakness, diarrhea and weakness, excessive salivation and/or regurgitation and/or colic, and weakness and incoordination and/or tremors. Based on these and accompanying signs in surviving animals, many of the causes of sudden death can be differentiated. In addition, pathological changes visible on necropsy and identification of plant fragments in the rumen and stomach may be of diagnostic value.  相似文献   

4.
Pairs of budgerigars were given samples, by gavage, of plants considered potentially toxic to pet birds. Samples were prepared by flash-freezing and powdering fresh plant material in liquid nitrogen and resuspending the material in deionized water for administration. Of the 19 plants tested, only 6 induced clinical signs of illness; these plants included yew, oleander, clematis, avocado, black locust, and Virginia creeper (Taxus media, Nerium oleander, Clematis sp, Persea americana, Robinia pseudoacacia, Parthenocissus quinquefolio).  相似文献   

5.
Pulmonary aspiration of oral, esophageal, or gastric content poses a significant hazard to animals. Aspiration of acidic, alkaline, or ingesta-containing gastric contents can cause serious morbidity and mortality. Clinicians must be aware of conditions and clinical situations in which there is increased risk of aspiration. The most important aspect of the mitigation of the pneumonic complications of aspiration is prevention.  相似文献   

6.
A 2-year-old bay Thoroughbred colt was found dead overnight in its stall without a known history of any illness, existing disease, or toxicant exposure. No information on the clinical signs before this animal's death was reported. A full necropsy was performed the next morning and revealed a mild to moderate degree of endocardial hemorrhages in both ventricles. Microscopic examination of the heart showed an acute mild multifocal necrosis of papillary muscles and ventricles. The stomach content contained approximately 2% Taxus alkaloids as determined by gas chromatography/mass spectrometry. In the past, diagnosis of Taxus poisoning has been mainly based on history of exposure and the presence of plant parts in the gastrointestinal tract. Pathological lesions associated with Taxus poisoning have not been published for horses. Therefore, this is the first report of cardiac lesions in a horse after lethal exposure to Taxus. On the basis of these findings, it is suggested that Taxus exposure needs to be considered in the differential diagnosis of horses that die suddenly or have cardiac lesions suggestive of Taxus exposure, even if intact plant parts are not identified in the stomach by the naked eye.  相似文献   

7.
The ultrasonographic findings in 13 canine patients with histopathologically proven gastric tumors were reviewed. The echogenicity of gastric wall lesions was variable and independent of the type of tumor. All dogs had an increase in gastric wall thickness and in only one dog was the wall layering intact. Regional lymph node involvement was a common finding, but abnormalities within the liver were seen in only one patient. Gastric neoplasia was observed most commonly in middle-aged and old, medium- to large-sized dogs. Carcinoma was the most common tumor found. In this study, with a limited number of animals and limited tumor types, it appeared that thickening of the gastric wall, accompanied by loss of gastric wall layering and enlargement of regional lymph nodes were ultrasonographic signs likely to be found with gastric neoplasia. In this limited study the histologic type of gastric tumor could not be predicted on the basis of the ultrasound examination.  相似文献   

8.
Two horses were accidentally administered propylene glycol instead of mineral oil. After discovery of the mistake intensive medical therapy with intravenous fluids, etc. was started, and both animals recovered fully from their clinical symptoms. Veterinarians use propylene glycol as well as paraffin routinely for the treatment of their patients. Mistakes are likely to be made because both medicines and sometimes their packing have a similar appearance. Several incidents have been reported in other countries. A large amount of propylene glycol given to a horse, but also to other animals, can be dangerous and immediate adequate intervention is necessary. The major cause of the problems in case of a propylene glycol intoxication is the high concentration of D-lactate that arises. Clinically, this primarily results in a depression of the central nervous system and in metabolic acidosis. Furthermore colic, diarrhoea and respiratory problems may occur.  相似文献   

9.
From the 62 swine abscesses examined, 56 yielded positive cultures, of which 38 cases were mixtures of facultative aerobes and obligate anaerobic bacteria (OAB). Only 6 species appeared to be sterile. In all specimens, which yielded OAB, VFA (C4-C6) could be detected by gas-liquid chromatography (GLC). False negatives were not recorded, and only one false positive was found, which might have been due to faulty culture technique, or to the fact that the metabolic markers may persist longer than the OAB themselves. Because current methods to isolate non-sporulating OAB are laborious and not available in most veterinary clinical situations and because there is a need to evaluate the importance of non-sporulating OAB in veterinary medicine, GLC seems to be a useful alternative to culture techniques for detecting the presence of OAB in infectious processes in animals.  相似文献   

10.
Growing rabbits from two rabbitries, fed with commercial concentrates and hay, developed painful thickenings of the extremities. Four rabbits from each farm were clinically examined and necropsied. All animals showed multiple moderate to severe osseous proliferations of extremities and mandibles and a mild to severe proliferative gastroduodenopathy. Histologically, periosteal and endosteal hyperostosis and a mild to severe proliferation of the gastric and duodenal mucosa were noted. Bone analyses revealed 12,700 and 15,000 microg fluoride per gram of bone ash in affected rabbits, compared with 550 microg fluoride in a control animal. A highly elevated fluoride content was found in concentrates. Vitamin A levels were moderately increased only in one concentrate, and copper levels were normal. Results indicate that alimentary fluoride intoxication caused prominent bony proliferations in the examined rabbits. Whether the proliferative gastroduodenopathy is related to the elevated fluoride intake or represents an incidentally occurring secondary disease remains to be determined.  相似文献   

11.
Sodium monofluoroacetate (Compound 1080) is a widely used pesticide for control of feral animals such as the fox. Accidental poisoning of domestic animals occurs despite strict regulations on 1080 usage. Dogs are particularly susceptible to the toxin. The mechanism of 1080 toxicity, susceptibility of target and non-target species, persistence of 1080 in the environment and risk of accidental poisoning are discussed. Particular emphasis is placed on 1080 toxicity in the dog. Early recognition of intoxication is most important for prognosis and relies upon characteristic clinical signs and diagnostic findings. The treatment of 1080 intoxication remains a challenge with no proven antidotes. However, there are possible benefits from monoacetin, acetamide, calcium salts, colestipol, activated charcoal, peritoneal dialysis, sodium bicarbonate, neurotransmitter modulators and four-methylpyrazole. A recommended treatment protocol for 1080 toxicosis in dogs is included. Safety measures such as the use of wire dog muzzles and investigating alternatives to 1080 in pest control programs may be the key to reducing the incidence of future accidental poisonings.  相似文献   

12.
Sodium monofluoroacetate, also known as compound 1080, is used in Australia for control of feral and pest species. Poisoning of non-target species by sodium monofluoroacetate can be difficult to diagnose if there is no history of exposure because clinical signs are non-specific. This communication describes the poisoning by sodium monofluoroacetate of seven dogs from one property over a period of 3 days. Poisoning by sodium monofluoroacetate was confirmed by toxicological analysis of stomach contents, gastric lavage fluid and vomitus from three of the dogs, but the source of the toxin was not found. Six of the seven dogs were Maremmas, and livestock guard animals may be at particular risk of exposure to pest control baiting programs.  相似文献   

13.
The presence of gastric parasites in winter-slaughtered calves and adult animals, was investigated. The number of parasites found was low in case of the calves indicating that gastric worms are of low significance concerning the winter losses. In case of adult animals was found a higher infestation indicating that gastric nematodes maybe of importance concerning the winter losses of 1,5 years old animals, Ostertagia leptospicularis was the only found species except for one animal in which was also present a few spiculopteragia alcis. The total dominance of Ostertagia leptospicularis means a marked difference from the findings of autumn-slaughtered reindeer bulls where Ostertagia leptospicularis was not found to be such a frequent finding but in addition several other species were found. In view of that is discussed a seasonal varation, winter ostertagiosis seems not to be a problem in reindeer calves.  相似文献   

14.
This article describes a case of massive mortality among horses which was probably due to intoxication by pyrrolizidine alkaloids from Heliotropium indicum. Over 4 years more than 75% of a population of about 110 horses on a farm in Costa Rica died after showing nervous neurological symptoms. Two clinical manifestations were encountered, an acute and a chronic one, both with a fatal outcome. Pathological findings in 2 horses coincided with those reported in the literature for intoxication by pyrrolizidine alkaloids and were not specific for VEE. However Venezuelan equine encephalitis (VEE) was the main differential diagnosis and could not completely be excluded because this disease was endemic in the region and VEE titres were found to be high. Taxonomic and toxicological investigations implicated Heliotropium indicum as the most probable principal cause of the intoxication.  相似文献   

15.
Clostridial infections are found worldwide in almost all species of animals and may involve a variety of body systems and present with a diversity of clinical signs. Most damage done through clostridial infections is due to the action of toxins released from the bacteria.Thus, disease caused by Clostridium spp should more correctly be called intoxication. Two prominent clostridial infections are associated with neurologic signs: Clostridium botulinum and C tetani. In both infections, the mechanism that is responsible for causing the problem is similar, despite the remarkable difference in clinical presentation. In addition, neurologic signs are described with C perfringens types C and D but are not the dominant feature of these diseases.  相似文献   

16.
The use of herbal remedies for the prevention and treatment of a variety of illnesses in small animals has increased tremendously in recent years. Whereas most herbal remedies, when used as directed and under the supervision of knowledgeable individuals, are safe, the potential for adverse effects or intoxications certainly exists. Due to inherent toxicity, some herbal remedies should not be used under any circumstance. In addition, because nearly all herbal remedies contain multiple, biologically active constituents, interaction with conventional drugs is a concern. It is incumbent upon clinicians to be aware of those herbs that can cause intoxication, and to be cognizant of potential herb-drug interactions. There are a number of evidence-based resources available to assist clinicians in the safe use of herbal remedies.  相似文献   

17.
Anamnesis and clinical signs of horses form five different stables after ingestion of ionophores are reported and techniques of feed examination are described. Within a few hours or days after feeding of new types or batches of concentrates horses fell ill. They showed colic-like symptoms with intense sweating and ataxia. Most of the sick animals died within a short time span. Samples of the concentrates were analysed and different types and amounts of ionophores were detected. In four cases contamination by monensin in concentrations of less than 5 mg to 679 mg/kg feed were found. One feed sample contained monensin (8.8 mg/kg feed) as well as salinomycin (67.3 mg/kg feed). In one case lasalocid (7.9 mg/kg feed) was present. One horse from the stable where animals had obtained concentrates containing monensin (679 mg/kg feed) was necropsied. Typical signs of monensin intoxication with severe myocardial degeneration were found. Veterinarians should be alert to this rare but severe intoxication of horses.  相似文献   

18.
We collected data on habitat use and locomotion of the François' langur (Trachypithecus francoisi) between August 2003 and July 2004 at Nonggang Nature Reserve, China. A total of 739 h of behavioral data were collected during this study. We tested 2 predictions: (1) that the langurs may have special patterns of habitat use and locomotion adaptive to the limestone habitat, and (2) the langurs may exhibit different patterns of habitat use and locomotion among different zones of limestone hill. Our results indicated that François– langurs spent more time in the low‐risk, relatively food‐poor cliff–hilltop areas. When young leaves and fruit were scarce in the dry season, the langurs increased their time in the high‐risk, food‐rich valley basin. François– langurs were semi‐terrestrial, and leaping and climbing were their main locomotor modes. These behavioral patterns are considered to be related to characteristics of topography and vegetation in limestone habitat, such as large areas of cliff and discontinuous canopy. Our results also supported Prediction 2. The langurs confined locomotion to the main canopy and frequently adopted leaping while traveling in the hillside and valley basin. While traveling in cliff–hilltop areas, they tended to stay in the lower stratus (≤5 m) or move on the ground, and walking and climbing were their dominant traveling modes.  相似文献   

19.
Protein species found in crude extracts of Hypoderma lineatum (Villers) 1st-instar gullet-stage larval homogenates were fractionated by chromatography and further identified by conventional polyacrylamide gel electrophoresis (PAGE) and SDS/PAGE techniques. Seven major fractions were resolved by ion exchange chromatography. Conventional PAGE of the crude antigen preparation revealed a minimum of 14 protein species, while SDS/PAGE revealed 3 major protein species. The ability to elicit cutaneous reactivity by isolated proteins was determined by the intradermal skin test. An immediate-type hypersensitivity reaction was elicited in the skin of vaccinated and previously infested animals by the components of the 4 protein fractions tested. Only one protein fraction, fraction 4, elicited an apparent delayed reaction at 48 h in vaccinated and previously infested animals. A non-specific background reaction was elicited in control animals by the fractionated proteins and was most notable between 1- and 4-h post-injection.  相似文献   

20.
Vitamin A transport in blood of most species in the order carnivora is fundamentally different from other animals and man. Very high levels of vitamin A in blood plasma of canines and mustelides are due to a high percentage of retinyl esters. These esters (basically retinyl palmitate and stearate) are transported nonspecifically bound to lipoproteins with very-low and low density lipoproteins representing the major fractions (about 70% of total vitamin A esters). A high percentage of retinyl esters could also be found in the families Ursidae, Procyonidae, Viverridae and Felidae in which total vitamin A in blood was low. In man and rat severe signs of vitamin A intoxication can be observed due to a similarly high percentage of nonspecifically bound vitamin A esters. No clinical or clinical-chemical signs of vitamin A intoxication were observed in the animals investigated. Because vitamin A esters are transported by lipoproteins, their blood levels are readily affected by dietary vitamin A supply as it is known to be the case for vitamin E. Furthermore, canines seem to be the only ones that excrete vitamin A as retinol and retinyl esters (basically retinyl palmitate) under physiological conditions with the urine. These fat-soluble metabolites of vitamin A are bound to a protein with a molecular weight between 50,000 and 125,000 Da which shows characteristics of a lipoprotein when subjected to ultracentrifugation or selective precipitation. Higher levels of vitamin A in organs and tissues, as well as the excretion of vitamin A with the urine, might be a consequence of the nonspecific binding of large amounts of retinyl esters to lipoproteins in blood.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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