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1.
C.R. Brown 《African Zoology》2013,48(4):166-172
Oxygen consumption of individual long-fingered bats, Miniopterus schreibersii, was measured at air temperatures (Tr) between 2 and 42°C and that of clusters of four and six bats between 5 and 30°C. BMR of individuals was estimated to be 2.29 ml O2 g 1 h-1 between 34 and about 38°C. M. schreibersii showed two different responses to Ta, either maintaining body temperature (Tb) by increasing metabolic rate, or allowing Tb to fall close to ambient temperature and conserving energy (torpor). Euthermic clusters of four and six bats had lower rates of mass-specific oxygen consumption and lower thermal conductances than individuals at equivalent temperatures and torpid clusters maintained a greater temperature differential between Tb and Ta. Lowest rates of metabolism were measured for euthermic bats at air temperatures higher than those available to them in their natural roost in summer, so typical roost temperatures result in metabolic rates that are about 2 4–3.1 times estimated BMR. Roost temperatures of M. schreibersii in South Africa are substantially higher in winter than are generally accepted as being suitable for hibernation but these do not substantially affect torpid metabolic rates, which are low and independent of ambient temperature below 22°C. Clearly at least some species of insectivorous bats are capable of hibernating at temperatures generally considered to be too warm for this activity.  相似文献   

2.
The purpose of this study was to provide a detailed computed tomographic (CT) anatomic reference for the dromedary camel tarsus. Six cadaver pelvic limbs, obtained from three clinically and radiographically sound dromedary camels, were scanned in both soft tissue and bone windows starting from the calcaneal tuber towards the proximal metatarsus. Limbs were frozen at ?20°C and sectioned transversely via an electric bone saw. The CT images were evaluated and correlated with their corresponding cryosections. The resulting images provided detailed anatomic features for bones, joints and soft tissue components of the tarsus and are intended to serve as a basic reference for the CT scanning of the dromedary camel tarsal pathology.  相似文献   

3.
A. Haim 《African Zoology》2013,48(1):67-70
Heat production measured as oxygen consumption (VO2 and heat dissipation calculated as the means of the overall thermal conductance were studied in a South African diurnal murid Lemniscomys griselda. This species maintains its body temperature (Tb) well at around 36,5 ± 1,0 °C over ambient temperatures (Ta) ranging between 5 and 34 °C. The thermoneutral zone lies between T a = 30-34 °C. When exposed to temperatures below the low critical point L. griselda at rest conforms to Newton's law of cooling. Non-shivering thermo- genesis (NST) was studied as a response to an injection of noradrenaline (sc). Following the administration of 1,5 mg noradrenaline per kg body mass to an anaesthetized animal, an increase of 329% in VO2 was recorded. The distribution pattern of L. griselda in comparison with that of Rhabdomys pumilio, the more common diurnal murid species in South Africa, is discussed.  相似文献   

4.
Transportation is often considered as one of the main causes of stress raising considerable interest, both in economic and animal welfare terms. The objective of the current study was to determine physiological response of dromedary camels to road transportation in relation to circulating levels of cortisol, thyroid hormones and some serum biochemical factors during summer conditions. Ten Iranian dromedary camels, five males and five females, were selected for the study. The study was conducted on three consecutive days in August 2008. At first day, blood samples were collected at 08:30 a.m., 09:30 a.m. and 01:30 p.m. to determine any possible variation in individual measurements due to diurnal changes or as a result of food and water deprivation for 5 h. Travel commenced on day 2 at 08:30 a.m. for 5 h, with a total of about 300 km traveled. At second day, blood samples were collected immediately before loading, at 08:30 a.m., after 1 h transport, at 09:30 a.m., and on the end of transportation, after unloading, at 01:30 p.m. Final blood sample was taken 24 h after arrival. In the current study no significant difference was observed in any parameter between sexes at each sampling time. The data related to day before transport had no significant differences between different times except for values obtained for cortisol that at 01:30 p.m. showed a significant decrease in comparison with data at 08:30 and 09:30. Circulating cortisol, T4, T3 and fT4 levels was significantly higher after transportation compared with pre-transport values and returned to basal values within 24 h after transport. Transportation had effects on metabolism as demonstrated by increase in serum concentrations of glucose, NEFA, and urea nitrogen. Serum concentrations of glucose, NEFA, and urea nitrogen returned to basal values in final bleeding at 24 h after transport termination. In the current study transportation had no significant effects on serum concentrations of fT3, triglycerides, cholesterol, β-hydroxybutyrate, albumin and total protein. Taken together, the results obtained for short road transportation of dromedary camels showed a strong physiological response and provide some biomarkers for stress detection in this species. Further research to validate these potential biomarkers is necessary.  相似文献   

5.
Middle East respiratory syndrome coronavirus (MERS‐CoV) is an emerging zoonotic disease. Exposure to dromedary camels (Camelus dromedaries) has been consistently considered the main source of primary human infection. Although Saudi Arabia reports the highest rate of human MERS‐CoV infection and has one of the largest populations of dromedary camels worldwide, their spatial association has not yet been investigated. Thus, this study aimed to examine the correlation between the spatial distribution of primary MERS‐CoV cases with or without a history of camel exposure reported between 2012 and 2019 and dromedary camels at the provincial level in Saudi Arabia. In most provinces, a high proportion of older men develop infections after exposure to camels. Primary human infections during spring and winter were highest in provinces characterized by seasonal breeding and calving, increased camel mobilization and camel–human interactions. A strong and significant association was found between the total number of dromedary camels and the numbers of primary camel‐exposed and non‐exposed MERS‐CoV cases. Furthermore, spatial correlations between MERS‐CoV cases and camel sex, age and dairy status were significant. Via a cluster analysis, we identified Riyadh, Makkah and Eastern provinces as having the most primary MERS‐CoV cases and the highest number of camels. Transmission of MERS‐CoV from camels to humans occurs in most primary cases, but there is still a high proportion of primary infections with an ambiguous link to camels. The results from this study include significant correlations between primary MERS‐CoV cases and camel populations in all provinces, regardless of camel exposure history. This supports the hypothesis of the role of an asymptomatic human carrier or, less likely, an unknown animal host that has direct contact with both infected camels and humans. In this study, we performed a preliminary risk assessment of prioritization measures to control the transmission of infection from camels to humans.  相似文献   

6.
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.  相似文献   

7.
Middle East respiratory syndrome coronavirus, MERS‐CoV, was identified in Saudi Arabia in 2012, and as of January 29, 2018, there were 2,123 laboratory‐confirmed MERS‐CoV cases reported to WHO (WHO, 2018, https://www.who.int/emergencies/mers-cov/en/ ). Multiple studies suggest that dromedary camels are a source for human MERS‐CoV infection. MERS‐CoV‐specific antibodies have been detected in the serum of dromedary camels across Northern Africa and across the Arabian Peninsula. Israel's geographic location places Israel at risk for MERS‐CoV infection. To date, MERS‐CoV‐related illness has not been reported and the burden of MERS‐CoV infection in the Israeli population is unknown. The seroprevalence of MERS‐CoV‐specific antibodies in Israeli dromedary camels is unknown. The objective of this study was to determine the prevalence of MERS‐CoV seropositivity in dromedary camels in Israel. The prevalence of MERS‐CoV antibodies in Israeli camels was examined in 71 camel sera collected from four farms across Israel by MERS‐CoV‐specific microneutralization (Mnt) assay and confirmed by MERS‐CoV‐specific immunofluorescence assay (IFA). Although this study cannot rule out potential antibody cross‐reactivity by IFA, the presence of bovine coronavirus‐specific antibodies do not appear to impact detection of MERS‐CoV antibodies by Mnt. MERS‐CoV neutralizing antibodies were detectable in 51 (71.8%) camel sera, and no association was observed between the presence of neutralizing antibodies and camel age or gender. These findings extend the known range of MERS‐CoV circulation in Middle Eastern camels. The high rate of MERS‐CoV‐specific antibody seropositivity in dromedary camels in the absence of any reported human MERS cases suggests that there is still much to be learned about the dynamics of camel‐to‐human transmission of MERS‐CoV.  相似文献   

8.
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9.
This study was performed to investigate the presence of bovine herpesvirus-1 (BHV-1), bovine leukemia virus (BLV) and bovine viral diarrhea virus (BVDV) infections in dromedary camels (Camelus dromaderius) kept in mixed herds with sheep and goats in Algeria, since the prevalence of BHV-1, BVDV, and BLV infections among dromedary camels in Algeria is unknown. Totally, 111 camel sera were collected from two provinces (Laghouat and Ghardaia) in Algeria. The sera were analyzed for BHV-1 specific antibodies, BVDV specific antibodies and BVDV antigen using the ELISA, and BLV nucleic acid using PCR. The seropositivity rate was 9.0% for BVDV-specific antibody, although 41.4% of camels tested were positive for BVDV antigen. Moreover, there was no evidence of BHV-1 and BLV infections. The results indicated that camels might represent an important source for BVDV infection in all ruminants, including cattle, sheep, and goats bred in mixed herds in Algeria, since they had a higher BVDV prevalence rates. Therefore, the prevention and control measures for BVDV infection should put in place in camel populations to limit the spread of BVDV infection to ruminant populations in Algeria.  相似文献   

10.
The genetic and demographic bottleneck analysis of Indian camel breeds was carried out utilizing 40 microsatellite markers. Allelic polymorphism was observed at 20 loci in the Indian dromedary breeds. A total of 66 alleles were scored. The average number of alleles, expected heterozygosity and polymorphic information content were, respectively, 3.25?±?0.27, 0.56?±?0.04 and 0.49?±?0.04 in Bikaneri; 3.25?±?0.25, 0.53?±?0.03 and 0.46?±?0.03 in Jaisalmeri; 3.0?±?0.21, 0.53?±?0.04 and 0.45?±?0.03 in Kachchhi and 3.1?±?0.19, 0.51?±?0.03 and 0.44?±?0.03 in Mewari breed. Higher genetic variation was observed in most numerous Bikaneri breed. Genetic distances were least between the breed pair Bikaneri and Jaisalmeri which was closely placed with the Kachchhi breed. The Mewari camels had relatively higher genetic distance from the other three Indian dromedary breeds. The bottleneck analysis revealed the presence of genetic bottleneck in all four breeds of Indian dromedary. However, the qualitative graphical method resulted in normal L-shaped distribution of allele frequencies in Jaisalmeri breeds and shifted mode in Bikaneri, Kachchhi and Mewari breeds. The demographic bottleneck analysis revealed minimum reduction (?9.65 %) in the population of camels in Jaisalmeri breeding tract as compared to that of Bikaneri (?14.18 %), Kachchhi (?27.78 %) and Mewari (?32 %) breeding tracts. Conclusively, the genetic bottleneck analysis could explain the demographic bottleneck in the Indian dromedary populations. Therefore, appropriate conservation and improvement efforts are needed in all four dromedary breeds with immediate attention on Mewari and Kachchhi breeds. The present study is the first report in demonstrating the genetic basis of demographic bottleneck in the Indian dromedary populations.  相似文献   

11.
Reference values were established for some haematological and serum biochemical constituents in Bactrian camels (Camelus bactrianus) in China. The contents of seven trace elements in the blood, hair, liver, kidney, heart, spleen, lung, cerebrum, cerebellum, rib, ovary, pancreas and gluteal muscle of Bactrian camels were also measured. Some of these values are reported for the first time for Bactrian camels in China. Most haematological and serum biochemical values were similar to those of cattle, yaks, sheep and dromedary camels, but the mean serum albumin concentration and the albumim/globulin ratio were significantly higher than those in other ruminants and the mean thyroxine concentration was half that in dromedary camels. The liver contained the highest concentrations of copper, zinc, manganese and iron, and the renal cortex contained the highest concentration of selenium. The concentrations of selenium, cobalt, zinc, manganese and molybdenum in the tissues were within the reference ranges for other ruminants, but the mean iron and copper concentrations in the liver were significantly higher than those in other ruminants.  相似文献   

12.
The experiment was undertaken on 20 pre-pubescent dromedary camels of 300?±?7.0 kg average bodyweight (BW) and 1.5–2 years of age to determine change in body weight, blood biochemical and mineral profiles and morphometric parameters on rangeland grazing (GR) and supplementary stall feeding (GS) at arid northwestern part of Rajasthan over a period of 80 days. GR camels were maintained only on grazing, while GS camels were fed semi-intensively ad-lib groundnut haulms along with formulated concentrate and mineral mixture to meet maintenance requirement. Intake of young camels was determined using chromium(III) oxide as internal marker. The biomass yield of rangeland estimated was 0.54 t DM/ha. Dry matter intake (kg/day) by GR camels on rangeland grazing was lower than that by GS camels fed on supplementary feeding. The nutrient digestibility of dry matter and organic matter (P?<?0.05) and crude protein was higher in GS camels than that in GR camels. Likewise, intake of digestible crude protein (P?<?0.05) and metabolizable energy were higher in stall-fed young camels. Pre-pubescent camels fed on grazing had significantly (P?<?0.01) low glucose and higher urea concentration compared to stall-fed camels. Final body weight of camels differed significantly (P?<?0.05) between groups. The camels fed on supplementary stall feeding had significantly (P?<?0.01) higher total gain (kg) and average daily gain (ADG) compared to camels on grazing. Among morphometric parameters, body length and body height showed more significant increase in GS compared to GR camels. Intake of digestible crude protein (DCP) by GR group was 43 % low compared to the requirement for growing camel of 300 kg body weight. Despite this, GR camels were able to maintain body weight due to better recycling of urea which was significantly higher in comparison to GS camels. The findings of significantly (P?<?0.01) low serum glucose and higher urea concentration and lower body weight gain of GR camels suggest the need of locally available protein and energy supplement in addition to grazing for better growth performance.  相似文献   

13.
Thoroughbred racehorses perform exercise at maximal intensities and typically display a hyperthermic exercise response, which can drive core body temperature to critical levels. Despite extremely efficient thermoregulatory mechanisms, certain weather conditions may affect the horse’s ability to cool and result in a syndrome referred to as exertional heat illness (EHI). This is characterised by central nervous system dysfunction, as well as cytotoxic effects of heat on cells, which can produce deleterious consequences. Early detection of exertional heat illness (EHI) in Thoroughbred racehorses can be difficult because signs are often vague and the measurement of rectal temperature as an indicator of hyperthermia is not practical. Best practice in the treatment of EHI in horses, as in human subjects, centres on early detection, rapid assessment and aggressive cooling. Research in human subjects has shown that EHI is manageable when recognised early and appropriate treatment provided. The aim of this study was to investigate the measurement of skin surface temperature (SST) by an infrared thermometer as an aid in the early detection of EHI. A skin surface temperature ≥39°C in the immediate postrace period is considered to be hot. It reflects the interaction of exercise-related metabolic heat production, physiological adjustments to the skin surface such as vasodilation and sweating, together with the effect of high ambient temperature. Most importantly, high SST is associated with a reduced core-to-skin temperature difference, which retards heat transfer from the deep body tissues to the skin and can hinder heat dissipation. Identification of horses with high SSTs can prioritise them for rapid cooling and curtail possible progression to EHI.  相似文献   

14.
Dairy cows with increased rectal temperature experience lower milk yield and fertility. Rectal temperature during heat stress is heritable, so genetic selection for body temperature regulation could reduce effects of heat stress on production. One aim of the study was to validate the relationship between genotype and heat tolerance for single nucleotide polymorphisms (SNPs) previously associated with resistance to heat stress. A second aim was to identify new SNPs associated with heat stress resistance. Thermotolerance was assessed in lactating Holsteins during the summer by measuring rectal temperature (a direct measurement of body temperature regulation; n = 435), respiration rate (an indirect measurement of body temperature regulation, n = 450) and sweating rate (the major evaporative cooling mechanism in cattle, n = 455). The association between genotype and thermotolerance was evaluated for 19 SNPs previously associated with rectal temperature from a genomewide analysis study (GWAS), four SNPs previously associated with change in milk yield during heat stress from GWAS, 2 candidate gene SNPs previously associated with rectal temperature and respiration rate during heat stress (ATPA1A and HSP70A) and 66 SNPs in genes previously shown to be associated with reproduction, production or health traits in Holsteins. For SNPs previously associated with heat tolerance, regions of BTA4, BTA6 and BTA24 were associated with rectal temperature; regions of BTA6 and BTA24 were associated with respiration rate; and regions of BTA5, BTA26 and BTA29 were associated with sweating rate. New SNPs were identified for rectal temperature (n = 12), respiration rate (n = 8) and sweating rate (n = 3) from among those previously associated with production, reproduction or health traits. The SNP that explained the most variation were PGR and ASL for rectal temperature, ACAT2 and HSD17B7 for respiration rate, and ARL6IP1 and SERPINE2 for sweating rate. ARL6IP1 was associated with all three thermotolerance traits. In conclusion, specific genetic markers responsible for genetic variation in thermoregulation during heat stress in Holsteins were identified. These markers may prove useful in genetic selection for heat tolerance in Holstein cattle.  相似文献   

15.
The rate of hair growth in the forehead, shoulder and flank regions of four normal-coated, cross-bred, male dogs maintained under the same controlled conditions of photoperiod, ambient temperature and diet, was measured during two six-week periods, one during summer and the other in winter. It was found that the rate of hair growth varied between individual dogs and also between the different regions in the same dog. Growth rate was most rapid in the shoulder region, followed by the flank and then the forehead regions, and was slightly more rapid in the shoulder and flank regions of three of the dogs during summer than in winter. Possible explanations for these variations in hair growth rate are discussed.  相似文献   

16.
An outbreak of Trypanosoma evansi infection that occurred in mainland Spain is described. The outbreak occurred on an equine and camel farm to which dromedary camels from an infected area of the Canary Islands had recently been introduced. One of these camels developed clinical signs and T. evansi was discovered in a blood smear examination. The herd was evaluated in order to determine the extent of the disease. The results showed that 76% of the camels, 35% of the donkeys and 2% of the horses were affected. The animals were isolated and treated using Cymelarsan® (0.5 mg/kg). After treatment, three blood analysis using parasitological methods revealed negative results. This is the first T. evansi outbreak to have occurred in mainland Spain and the second in mainland Europe, both occurring after the introduction of dromedary camels from the Canary Islands.  相似文献   

17.
ObjectiveTo evaluate the clinical and physiological effects of epidural injection of ketamine in camels.Study designRandomized prospective study.AnimalsTen healthy immature male dromedary camels.MethodsKetamine was administered epidurally at doses of 1 and 2 mg kg?1 (five animals in each treatment). The drug was injected into the first intercoccygeal epidural space. Anti-nociception, sedation, ataxia, and effect on cardiopulmonary, rectal temperature and some selected haematological parameters were recorded at different intervals before (baseline) and after the drug administration. Data were analyzed by anova or U Mann–Whitney tests, as relevant and significance was taken as p < 0.05.ResultsEpidural ketamine at the 2 mg kg?1 dose produced complete anti-nociception in the tail, anus and perineum, whilst the 1 mg kg?1 dose produced complete anti-nociception only in the tail. Epidural ketamine resulted in mild to moderate sedation at the 1 mg kg?1 dose and deep sedation at the 2 mg kg?1 dose. Ataxia was observed in all test subjects and was severe, resulting in recumbency, in the 2 mg kg?1 group. Respiratory rate and rectal temperature did not change significantly after injection of either treatment. Following epidural injection of 2 mg kg?1 of ketamine, heart rate increased significantly from the pre-injection baseline of 55 ± 2 to 76 ± 4 (mean ± SD) beats minute?1, but after the lower dose changes were not significant. The only significant changes in measured haematologic parameters were decreases in total erythrocyte count at 45 minutes and total leukocyte count from 45–75 minutes, in the 2 mg kg?1 group.ConclusionEpidural ketamine injection was associated with caudal anti-nociception, sedation and ataxia in the dromedary camels; the intensity and duration of which was dose dependant.Clinical relevanceNeither of the doses of epidural ketamine injection in our study was applicable for standing surgical procedures in dromedary camels.  相似文献   

18.
The present study aimed to isolate and genotype C. perfringens from healthy and diarrheic dromedary camels, pastures and herders; and to evaluate and compare antimicrobial susceptibility of the isolates. A total of 262 (56.3%) C. perfringens isolates were recovered from 465 samples of healthy and diarrheic dromedary camels, pastures and herders. C. perfringens type A (75.2%), type B (4.2%), type C (13.7%) and type D (6.9%) were detected. C. perfringens type A with only cpa+ gene was found in 191 (72.9%) isolates and with cpa+ associated cpb2+ was found only in 6 (2.3%) isolates. None of the isolates were positive for cpe and iap genes.The highest antimicrobial resistance (82.8%) was observed to ceftiofur with MIC50 and MIC90 values of <64 and ≥256 μg/mL, respectively, followed by penicillin G (72.9%) and erythromycin (61.5%). The lowest resistance (1.9%) was observed for doxycycline with MIC50 and MIC90 values of <1 and 4 μg/mL, respectively, followed by florfenicol (5.3%) and clindamycin (12.2%). In conclusion, C. perfringens type A with cpa+ gene was the most prevalent toxin type isolated in this study. The majority of the isolates were resistant to at least one of the ten antimicrobials tested. Antimicrobial resistance patterns of C. perfringens isolates provide further evidence on the emergence of multiple-drug resistant C. perfringens. Therefore, the dissemination of surveillance programs to monitor and control C. perfringens in dromedary camels is required.  相似文献   

19.
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20.
The effects of either xylazine (0.25 mg/kg) intramuscularly, ketamine (5.5 mg/kg) intramuscularly, or a mixture of xylazine (0.15 mg/kg) and ketamine (2.5 mg/kg) intramuscularly on sedation, analgesia, cardiac and respiratory rates, body temperature and muscle relaxation were studied in the domesticated dromedary camel. Either drug used separately was suitable for sedation and analgesia in the camel. However, the mixture of xylazine and ketamine was superior to either drug used alone. Camels which received the combination of xylazine and ketamine had fewer effects on cardiac and respiratory rates and better analgesia. In addition, they showed better muscle relaxation, less central nervous system irritability and shorter recovery times than camels sedated with ketamine alone.  相似文献   

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