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1.
Order Chiroptera is the second largest mammal group after rodents. An understanding of the development of the bats, which is a very special mammal group in terms of their lifestyles, morphology and their ability to fly, is very important because most of the adult anatomical differences characterizing species occur during organogenesis. In this study, developmental stages were determined for Myotis myotis species based on external morphological characteristics from embryos obtained from wild‐caught pregnant females. The developmental stages of M. myotis were comparable with those of other bat species.  相似文献   

2.
Extractive foraging (EF) involves the exploitation of hidden or embedded foods, generally any food that is not visible to the naked eye. Therefore, EF is particularly important for survival in marginal habitats as it provides seasonal fallback foods in low food availability seasons. Although many studies consider primates’ EF behavior and category, colobine species are usually categorized as non‐extractive foragers and few studies quantitatively examine their EF behavior. In this study, we examined the EF behavior of one colobine species, the gray snub‐nosed monkey (Rhinopithecus brelichi), at Yangaoping in Fanjingshan National Nature Reserve, Guizhou. We recorded 6 categories of EF behaviors. The most frequently sought‐out foods were seeds, young bamboo and invertebrates. Extracted foods accounted for an average of 26.02% of feeding records. As the monkey engages in little EF behavior in the winter when the food availability is low, these results seem to do not support the hypothesis that EF serves to secure additional resources during lean times in marginal or seasonal habitats. According to these findings, we suggest R. brelich should be considered as an extractive forager. Our study also highlights the need for increased representation of colobines in the EF literature to better inform the discussion concerning its link to primate brain evolution.  相似文献   

3.
In this study, effects of grazing‐experienced heifer presence on foraging behavior development at the feeding station (FS) scale for first‐grazing season calves were determined. A group of four calves grazing alone (C), and another comprising four calves (Wc) and three grazing‐experienced heifers (Wh), were alternately stocked every day for 2 h on the same pasture for 26 days. The foraging time budget for Wc was significantly longer than that for C (P < 0.05) on day 7, and was similar to that for Wh on all days. Bite rate per FS was significantly higher for Wc (15.5 bite/min) than for C (13.2 bite/min) from day 1 to 14 (33.4 vs. 29.0 bite/min, respectively; P < 0.01) and significantly lower than that for Wh on all days. The number of steps taken between adjacent FSs by Wc (4.7) was significantly lower than that for C (7.2) on days 1 and 14 (2.1 vs. 2.9 steps, respectively; P < 0.01) and was similar to Wh on all days. This suggests that grazing‐experienced heifers have positive effects on the foraging behavior development of new‐season grazing calves through 14 days after the start of stocking.  相似文献   

4.
The foraging technique and prey‐handling time of the black‐necked stork (Ephippiorhynchus asiaticus) was studied in Dudhwa National Park, India, from January 1996 to June 1997. The habitat in which the storks foraged played an important role in selecting a particular technique to procure food. Black‐necked storks mostly foraged using a tactile technique (>90%), but sometimes foraged visually. When the water level was estimated to be less than 60 cm, the storks foraged using tactile techniques. There was no difference in the feeding techniques of male and female storks. Foraging attempt rates varied between the sexes in summer (May) and during late winter (February) in 1997. The search time for prey increased when the water level was high and fish were widely distributed. Decreases in water level resulted in concentration offish in certain areas and this contributed to high fish‐catching rates by black‐necked storks. Males had a higher success rate offish capture than females. However, females captured longer fish than males. Prey‐handling time increased in both sexes as fish length increased. Fish 4–6 cm long were most frequently taken by the foraging storks.  相似文献   

5.
Forest‐grazing enables the intake of high total antioxidant capacity (TAC) plants that might be beneficial for the TAC status of cattle. This study evaluated the relation between the seasonal foraging patterns of forest‐grazing Japanese Black (JB) heifers or the TAC levels in shrubs and trees and the changes of plasma TAC. We examined 12 JB heifers, four each of which were allocated to forest‐grazing (F), pasture‐grazing, and pen‐housed groups. The plasma TAC level in F heifers on July 26, August 13, 30 and September 17 were significantly higher than those on April 27 and June 4 (P < 0.05). In F group, the mean rates of foraging frequency (FF) of shrubs and trees during July 5–8 and September 13–16 were much higher than that during May 31–June 3 (P < 0.05). The rate of FF of grass significantly decreased later in the season (P < 0.05). The mean TAC levels in these shrubs and trees were higher than those in grasses, concentrates, and timothy hay. Results suggest that an important factor in the increase of plasma TAC in forest‐grazing cattle might be the increased foraging of TAC‐rich shrubs and trees during summer–fall.  相似文献   

6.
The aim of this study was to examine the histomorphometric and histochemical structure of oesophagus of the wild-caught greater mouse-eared bat Mmyotis. For this purpose, 10 specimens of oesophagus were collected and processed. The oesophagus wall of Mmyotis is composed of four layers: tunica mucosa, tunica submucosa, tunica muscularis and tunica adventitia. The mucosa is covered by a non-keratinized stratified squamous epithelium. There were no glands in the wall of the oesophagus. Tunica muscularis is composed of two muscle layers: internal circular muscular layer and an external longitudinal muscular layer. Histochemical studies revealed that the oesophagus was AB/PAS and PAS positive indicating the presence of acidic and neutral mucosubstances. AB-PAS staining shows that glycoproteins were predominant in the all examined layers of the oesophagus. Because of the absence of oesophageal glands in Mmyotis, positive reaction with AB-PAS staining may be due to secretion of salivary glands. Absence of oesophageal glands reflects the functional adaptation as high food passage rate for the insectivorous feeding habits of animals.  相似文献   

7.
The Damaraland mole‐rat is a subterranean mammal exhibiting extreme reproductive skew with a single reproductive female in each colony responsible for procreation. Non‐reproductive female colony members are physiologically suppressed while in the colony, exhibiting reduced concentrations of plasma luteinizing hormone (LH) and a decreased response of the pituitary, as measured by the release of bioactive LH, to an exogenous dose of gonadotrophin releasing hormone (GnRH). Removal of the reproductive female from the colony results in an elevation of LH and an enhanced response of the pituitary to a GnRH challenge in non‐reproductive females comparable to reproductive females, implying control of reproduction in these individuals by the reproductive female. The Damaraland mole‐rat is an ideal model for investigating the physiological and behavioral mechanisms that regulate the hypothalamo–pituitary–gonadal axis. In contrast, we know less about the control of reproduction at the level of the hypothalamus. The immunohistochemistry of the GnRH system of both reproductive and non‐reproductive female Damaraland mole‐rats has revealed no significant differences with respect to morphology, distribution or numbers of immunoreactive GnRH perikarya. We examined whether the endogenous opioid peptide beta‐endorphin was responsible for the inhibition of the release of the GnRH from the neurons indirectly by measuring LH concentrations in these non‐reproductive females following single, hourly and 8 hourly injections of the opioid antagonist naloxone. The results imply that the endogenous opioid peptide, beta‐endorphin, is not responsible for the inhibition of GnRH release from the perikarya in non‐reproductive females. Preliminary data examining the circulating levels of cortisol also do not support a role for circulating glucocorticoids. The possible role of kisspeptin is discussed.  相似文献   

8.
为了解高原鼢鼠(Myospalax baileyi)挖掘活动对采食洞道土壤水肥的影响,在祁连山东段高寒草甸同一放牧强度区,对高原鼢鼠活动洞道、非活动洞道、无洞道土壤的容重、水分、有机质、全氮以及速效N,P和K含量进行了测定,并通过One-Way ANOVA检验和T检验进行比较分析。结果表明,高原鼢鼠的挖掘活动对土壤速效P、K无显著影响(P0.05),但会增加洞道土壤容重及20~30cm土层有机质、全氮、速效氮含量(P0.05),减少0~10cm土层土壤含水量及速效氮含量(P0.05),导致洞道土壤部分营养成分垂直方向的变化。  相似文献   

9.
Group living provides various advantages to individuals in regards to protection avoidance, intergroup competition, productive success and social information. Stable one‐male units (OMUs) consist of relationships between the adult females and the resident male as well as the relationships among adult females. Based on continuous observation of a reproductive group of golden snub‐nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains, we analyzed the relationships among adult individual dyads within 4 OMUs. The results indicated that in golden snub‐nosed monkey societies, females not only had no strong tendency to build a relationship with the resident male in the OMU but also had no strong tendency to build relationships with other females in the OMU. In comparison with hamadryas (Papio hamadryas) and gelada baboons (Theropithecus gelada), the relationships within golden snub‐nosed monkeys OMUs showed neither the star‐shaped pattern observed in hamadryas baboons nor the net‐shaped pattern observed in gelada baboons. We concluded that the relationships within golden snub‐nosed monkey OMUs indicated a third pattern in nonhuman primate societies. Future research is required to determine the potential mechanisms for such a pattern.  相似文献   

10.
To determine the bioavailability and pharmacokinetic properties of the serotonin 5‐HT1A receptor agonist R‐8‐OH‐DPAT in goats, and 0.1 mg kg?1 R‐8‐OH‐DPAT hydrobromide was administered intramuscularly (i.m.) and intravenously (i.v.) to six goats in a two‐phase cross‐over design experiment. Venous blood samples were collected from the jugular vein 2, 5, 10, 15, 20, 30, 40 and 60 min following treatment and analysed by liquid chromatography tandem mass spectrometry. Bioavailability and pharmacokinetic parameters were determined by a one‐compartment analysis. Mean bioavailability of R‐8‐OH‐DPAT when injected i.m. was 66%. The mean volume of distribution in the central compartment was 1.47 L kg?1. The mean plasma body clearance was 0.056 L kg?1 min?1. All goats injected i.v. and two of six goats injected i.m. showed signs of serotonin toxicity. In conclusion, R‐8‐OH‐DPAT is well absorbed following i.m. injection and the observed pharmacokinetics suggest that administration via dart is feasible. Administration of R‐8‐OH‐DPAT hydrobromide, at a dosage of 0.1 mg kg?1, resulted in the observation of clinical signs of serotonin toxicity in the goats. It is suggested that dosages for the clinical use of the compound should be lower in order to achieve the desired clinical effect without causing serotonin toxicity.  相似文献   

11.
12.
In Italy, the first human case of West Nile Virus (WNV) infection was reported in 2008 and, since then, the number of cases has been steadily increasing. In this study, we describe the temporal and spatial pattern of WNV infection risk among humans in Italy, focusing on the human cases of West Nile Neuro‐invasive Disease (WNND) observed between 2008 and 2017. Incidence rates are estimated for each year and province under study. The incidence temporal trend is estimated using Poisson regression, and a spatio‐temporal cluster detection analysis is performed to detect high‐risk areas. In total, 231 WNND cases were notified in Italy between 2008 and 2017. The annual incidence rates increased during the study period (annual percentage change: 11.7%; 95%CI: ?0.9%; 26.1%). A geographical spread of the disease was observed during the study period throughout Northern Italy, with an increasing number of affected provinces. Provinces close to the Po River (the main river in the north of Italy) and the Oristano province (in the Sardinia Island) experienced the highest incidence rates during the study period. Our study shows a gradual, but rapid spread of WNND across Northern Italy from east to west and suggests the hypothesis that provinces close to Po River might present ecological and climatic conditions favourable to the virus circulation.  相似文献   

13.
We analyzed the urinary excretion of glucose and N‐acetyl‐β‐D‐glucosaminidase (NAG) in six okapis (Okapia johnstoni) in captivity to investigate the cause of their urinary sugar excretion. The urinary glucose‐positive okapi had significantly higher urinary NAG indices than the urinary glucose‐negative okapi. There was also a positive correlation between urinary glucose levels and urinary NAG indices. These results suggest that the proximal tubular function of the glycosuric okapi may have been obstructed, which impaired glucose reabsorption.  相似文献   

14.
The intensification of dog, cat and livestock vaccination campaigns significantly reduced rabies cases in humans and domestic animals in Ceará State, Brazil. However, sylvatic animals—bats (order Chiroptera), wild canids, raccoons and non‐human primates— remain as reservoirs for the virus. Our hypothesis is that surveillance and monitoring of rabies virus in bats, especially passive surveillance, is of fundamental importance, besides the implementation of health education and strengthening of surveillance actions in humans exposed to aggressions. Thus, we assessed the occurrence of rabies virus in animals focusing on bats, before and after launching of the Sylvatic Rabies Surveillance Program in 2010. Surveillance data from the 184 municipalities of Ceará State were analysed, collected during the periods 2003–2010 (active surveillance) and 2011–2016 (passive surveillance), respectively. A total of 13,543 mammalian samples were received for rabies diagnosis from 2003 to 2016. Of these, 10,960 were from dogs or cats (80.9%), 1,180 from bats (8.7%), 806 from other sylvatic animals (foxes, marmosets, raccoons; 6.0%) and 597 from herbivores (cattle, goats, sheep, equines, pigs; 4.4%). A total of 588 (4.3%) samples were positive for rabies. About 8.4% (99/1,180) of the bat samples were infected with rabies virus, 92 (92.9%) of these were from non‐haematophagous bat species and 7 (7.1%) from haematophagous species. The number of bat samples received and infection rates increased considerably, after a shift from active surveillance (9/355 [2.5%] samples positive), to passive surveillance (90/825 [10.9%] samples positive). Surveillance of rabies virus in bats is fundamental for human and domestic animal health in Ceará State. Bats have to be considered as targets in surveillance and control programmes. Virus lineages should be characterized to increase knowledge on transmission dynamics of sylvatic rabies virus to domestic animals and the human population, and to provide additional evidence for planning and implementation of improved control measures.  相似文献   

15.
This study investigated the prevalence of MRSA in samples taken in households, with and without backyard pigs in villages in a rural area of Shandong Province, China. Community‐associated MRSA and livestock‐associated MRSA, belonging to ST59 and ST9, respectively, were identified in both humans and pigs. The genotypic and phenotypic comparison of isolates indicates that bidirectional transmission of MRSA has occurred between humans and pigs in the villages.  相似文献   

16.
Toxoplasma gondii infections cause a large disease burden in the Netherlands, with an estimated health loss of 1,900 Disability Adjusted Life Years and a cost‐of‐illness estimated at €44 million annually. Infections in humans occur via exposure to oocysts in the environment and after eating undercooked meat containing tissue cysts, leading to asymptomatic or mild symptoms, but potentially leading to the development of ocular toxoplasmosis. Infection in pregnant women can lead to stillbirth and disorders in newborns. At present, prevention is only targeted at pregnant women. Cat vaccination, freezing of meat destined for undercooked consumption and enhancing biosecurity in pig husbandries are possible interventions to prevent toxoplasmosis. As these interventions bear costs for sectors in society that differ from those profiting from the benefits, we perform a social cost‐benefit analysis (SCBA). In an SCBA, costs and benefits of societal domains affected by the interventions are identified, making explicit which stakeholder pays and who benefits. Using an epidemiological model, we consider transmission of T. gondii after vaccination of all owned cats or cats at livestock farms. To identify relevant high‐risk meat products that will be eaten undercooked, a quantitative microbial risk assessment model developed to attribute predicted T. gondii infections to specific meat products will be used. In addition, we evaluate serological monitoring of pigs at slaughter followed by an audit and tailor made advice for farmers in case positive results were found. The benefits will be modelled stochastically as reduction in DALYs and monetized in Euro's following reference prices for DALYs. If the balance of total costs and benefits is positive, this will lend support to implementation of these preventive interventions at the societal level. Ultimately, the SCBA will provide guidance to policy makers on the most optimal intervention measures to reduce the disease burden of T. gondii in the Netherlands.  相似文献   

17.
ObjectivesTo evaluate the cardiorespiratory and biochemical effects of ketamine-propofol (KP) or guaifenesin-ketamine-xylazine (GKX) anesthesia in donkeys.Study designProspective crossover trial.AnimalsEight healthy, standard donkeys, aged 10 ± 5 years and weighing 153 ± 23 kg.MethodsDonkeys were premedicated with 1.0 mg kg?1 of xylazine (IV) in both treatments. Eight donkeys were administered ketamine (1.5 mg kg?1) and propofol (0.5 mg kg?1) for induction, and anesthesia was maintained by constant rate infusion (CRI) of ketamine (0.05 mg kg?1 minute?1) and propofol (0.15 mg kg?1 minute?1) in the KP treatment. After 10 days, diazepam (0.05 mg kg?1) and ketamine (2.2 mg kg?1) were administered for induction, and anesthesia was maintained by a CRI (2.0 mL kg?1 hour?1) of ketamine (2.0 mg mL?1), xylazine (0.5 mg mL?1) and guaifenesin (50 mg mL?1) solution. Quality of anesthesia was assessed along with cardiorespiratory and biochemical measurements.ResultsAnesthetic induction took longer in GKX than in KP. The induction was considered good in 7/8 with KP and in 6/8 in GKX. Anesthetic recovery was classified as good in 7/8 animals in both treatments. Xylazine administration decreased heart rate (HR) in both treatments, but in KP the HR increased and was higher than GKX throughout the anesthetic period. Respiratory rate was higher in GKX than in KP. PaO2 decreased significantly in both groups during the anesthetic period. Glucose concentrations [GLU] increased and rectal temperature and PCV decreased in both treatments. Arterial lactate [LAC] increased at recovery compared with all time points in KP. [GLU] and calcium were higher in GKX than in KP at recovery.Conclusion and clinical relevanceThese protocols induced significant hypoxemia but no other cardiorespiratory or metabolic changes. These protocols could be used to maintain anesthesia in donkeys, however, they were not tested in animals undergoing surgery.  相似文献   

18.
There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point‐of‐care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range.  相似文献   

19.
Influences of a specific dietary nutrient on glucagon‐like peptide (GLP)‐1‐containing cells in the chicken intestine are not yet clear. Significance of dietary protein level on GLP‐1‐containing cells in the chicken ileum was investigated. Chickens fed control or experimental diets of varying protein levels were examined using immunohistochemical and morphometrical techniques. We show that the protein ingestion had an impact on the activities of GLP‐1‐immunoreactive cells in the chicken ileum. Weight gains declined with decreasing dietary crude protein (CP) levels, but no significant differences were detected in the daily feed intake and villous height. GLP‐1‐immunoreactive cells with a round or oval shape were frequently observed in the lower CP level groups (4.5% and 0%). Frequencies of occurrence of GLP‐1‐immunoreactive cells were 41.1 ± 4.1, 38.5 ± 4, 34.8 ± 3.1 and 34.3 ± 3.7 (cells/mm2, mean ± SD) for dietary CP level of 18%, 9%, 4.5% and 0% groups, respectively and significant differences were recognized between the control and lower CP level groups (P < 0.05). Multiple regression analysis indicated a significant correlation between the daily protein intake and frequencies of occurrence of GLP‐1‐immunoreactive cells. The protein ingestion is one of the signals that influence GLP‐1‐containing cells in the chicken small intestine.  相似文献   

20.
CTX‐M‐type extended‐spectrum β‐lactamase (ESBL)‐producing Enterobacteriaceae have become identified in marine ecosystem constituting a serious ecological issue. In this respect, although contamination of coastal waters and seafood, and even colonization of seabirds and fishes have been increasingly reported, molecular data are lacking to elucidate the clinical impact of ESBL producers in infected marine animals. In this study, using a genomic approach, we have analysed the genetic background of CTX‐M‐15‐producing Enterobacter hormaechei (belonging to the international human clone ST114) and Citrobacter freundii (ST265) co‐infecting a free‐living green turtle (Chelonia mydas) suffering from septic arthritis, which progressed to generalized coelomitis and death. Wide resistome of these pathogens contributed to treatment failure and death of the animal.  相似文献   

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