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1.
A nickel (Ni)-plated copper-solid bullet type released up to 93 μg Ni /10 g bullet mass when immersed into meat juice for 7 days (to simulate fragments remaining in venison). A non-nickel-plated counterpart of identical construction released no Ni, but up to 250 μg copper. During thermal processing of pork cubes with embedded bullets, an average of 2.8 and up to 4.3 (maximum) μg Ni were released from the Ni-plated bullet to the surrounding meat. Average nickel and copper content in meat samples (taken in 2–3 cm distance from the shot wounds) from 30 roe deer (Capreolus capreolus) and 3 sika deer (Cervus nippon) killed with nickel-plated copper bullets did not differ significantly from those in controls (roe deer haunch). Contamination scenarios would Cu and Ni contents per portion increase moderately by 20 and 3.3 μg, respectively. In order to limit alimentary Ni uptake, the technological need for Ni-plating of bullets should be carefully evaluated.  相似文献   

2.
Abstract: Although lead shot has been banned for waterfowl hunting in North America, some predators continue to exhibit elevated lead burdens, which has been attributed to ingesting metallic lead from other projectiles. Few studies have investigated residual lead fragments in hunted upland animals. Therefore, specific portals for lead entering wildlife food chains remain largely unknown. Prairie dogs (Cynomys spp.) are shot for recreation with minimal regulation in western North America. Because recreational shooters mostly use expanding bullets and rarely remove or bury carcasses, shot prairie dogs could make lead accessible to predators and scavengers. To determine whether and to what degree shot prairie dogs carry lead fragments, we analyzed carcasses shot by recreational shooters with 2 bullet types. Bullet type influenced the probability of bullet fragments being retained in carcasses; 87% of prairie dogs shot with expanding bullets contained bullet fragments, whereas 7% of carcasses shot with non-expanding bullets did. The amount of bullet fragments per carcass also differed between bullet types; carcasses shot with expanding bullets contained a mean of 228.4 mg of the lead-containing bullet core and 74.4 mg of the copper-alloy jacket, whereas carcasses shot with non-expanding bullets averaged only 19.8 mg of the core and 23.2 mg of the jacket. Lead fragments in carcasses shot with expanding bullets were small in size; 73% of all lead mass in each carcass was from fragments that weighed <25 mg each, small enough to be easily ingested and absorbed by secondary consumers. The amount of lead in a single prairie dog carcass shot with an expanding bullet is potentially sufficient to acutely poison scavengers or predators. Therefore, shot prairie dogs may provide an important portal for lead entering wildlife food chains and may pose risks to raptors and carnivores. Managers should consider measures, such as using non-expanding or lead-free ammunition, to reduce the likelihood of lead consumption and poisoning in upland wildlife.  相似文献   

3.
Human consumers of wildlife killed with lead ammunition may be exposed to health risks associated with lead ingestion. This hypothesis is based on published studies showing elevated blood lead concentrations in subsistence hunter populations, retention of ammunition residues in the tissues of hunter-killed animals, and systemic, cognitive, and behavioral disorders associated with human lead body burdens once considered safe. Our objective was to determine the incidence and bioavailability of lead bullet fragments in hunter-killed venison, a widely-eaten food among hunters and their families. We radiographed 30 eviscerated carcasses of White-tailed Deer (Odocoileus virginianus) shot by hunters with standard lead-core, copper-jacketed bullets under normal hunting conditions. All carcasses showed metal fragments (geometric mean = 136 fragments, range = 15–409) and widespread fragment dispersion. We took each carcass to a separate meat processor and fluoroscopically scanned the resulting meat packages; fluoroscopy revealed metal fragments in the ground meat packages of 24 (80%) of the 30 deer; 32% of 234 ground meat packages contained at least one fragment. Fragments were identified as lead by ICP in 93% of 27 samples. Isotope ratios of lead in meat matched the ratios of bullets, and differed from background lead in bone. We fed fragment-containing venison to four pigs to test bioavailability; four controls received venison without fragments from the same deer. Mean blood lead concentrations in pigs peaked at 2.29 µg/dL (maximum 3.8 µg/dL) 2 days following ingestion of fragment-containing venison, significantly higher than the 0.63 µg/dL averaged by controls. We conclude that people risk exposure to bioavailable lead from bullet fragments when they eat venison from deer killed with standard lead-based rifle bullets and processed under normal procedures. At risk in the U.S. are some ten million hunters, their families, and low-income beneficiaries of venison donations.  相似文献   

4.
Lead remnants from spent ammunition introduce health risks to humans and wildlife that consume game harvested with firearms. Most current research has focused on effects of high-velocity rifle bullets, whereas low-velocity lead ammunition has received little attention. We examined whether fragmentation characteristics differed between 3 common low-velocity ammunition types when shot into the thoracic cavity or shoulder of white-tailed deer (Odocoileus virginianus) culled in Indiana, USA, from May–September of 2009. We shot and subsequently radiographed 43 deer to determine the number of fragments, fragment size, and distance traveled by individual fragments. We also radiographed deer post-evisceration to determine the proportion of fragments available to humans and wildlife scavengers for consumption in muscle and visceral tissue, respectively. All radiographed deer had evidence of fragmentation, with a geometric mean of 13.1 (95% CI = 10.3, 16.8) fragments/deer. Most fragments (89%) were <5 mm from wound channels, and no fragment traveled beyond 205 mm from a wound channel. Fragments were often retained within the muscle tissue of deer with a geometric mean rate of 0.55 (95% CI = 0.48, 0.65). Muzzleloader bullet fragments were larger than those generated by rifled and sabot slugs, and sabot slug fragments had the shortest dispersal from wound channels. Shoulder-shot placement and bone contact for all ammunition resulted in a greater number of fragments (P < 0.01). Shoulder-shots also generated more small fragments and higher fragment retention in muscle tissue. The overall mean number of lead fragments detected across our ammunition treatments was less than previous studies. Our results indicate ammunition type and shot placement may be considerations for hunters wishing to limit their potential exposure to lead from harvested big game. Additionally, when compared to high-velocity rifle bullets, significantly fewer lead fragments are made available to humans and wildlife that consume game harvested with low-velocity ammunition types, such as those tested here. Complete elimination of lead ingestion by humans and wildlife, however, is only possible by using non-toxic ammunition alternatives. © 2020 The Wildlife Society.  相似文献   

5.
Sharpshooting is a proven management technique to lower white-tailed deer (Odocoileus virginianus) densities in areas where hunting is precluded. A donation program that allows for the consumptive use of these culled deer is often necessary to gain public approval for such a program. We culled 40 deer in Indiana using sharpshooting methods (head and neck shot placement) and radiographed the carcasses to determine if lead fragmentation spread throughout the skeletal muscle system. In 30 deer where shot placement was between the cranium and fourth cervical vertebrae, we observed no lead fragments in any thoracic or crural muscle tissue. Of 10 deer where shot placement was between the fifth and seventh cervical vertebrae, 8 deer experienced lead fragments in the extensor spinae muscle. Deer culled with highly frangible bullets via sharpshooting in the cranium or upper cervical spine have minimal risk of experiencing lead fragmentation in the thoracic or crural muscle systems. Deer shot in the lower neck may experience lead fragmentation in the anterior extensor spinae muscle, and up to 40 cm of that muscle should be removed before consumption. © 2011 The Wildlife Society.  相似文献   

6.
《Small Ruminant Research》2008,76(2-3):185-191
General health, clinical-chemical blood analysis and copper (Cu), zinc (Zn), selenium (Se) and vitamin E concentrations in plasma and liver tissue (wet weight, ww) of two extensive grazing sheep flocks without mineral supply were compared to the status of local roe deer (Capreolus capreolus) populations (liver samples). Both sheep flocks were classified as healthy except for a remarkable variation in body weight and a slight foot rot infection in one flock. Hematology of sheep was normal, and total protein and creatinine as well as activities of creatin kinase, aspartat-amino-transferase, alkaline phosphatase and gamma-glutamyl-transferase in plasma were within reference levels. The mean of glutamate dehydrogenase (13.8 U/l) was slightly elevated in one flock. Mean liver concentrations of Zn (38.9 and 43.5 mg/kg ww) and Cu (111 and 87.5 mg/kg ww) in sheep flocks were higher compared to the respective roe deer populations (27.5 and 36.3 mg Zn/kg ww; 18.3 and 28.6 mg Cu/kg ww). This is supposed to be caused by differences in Cu and Zn metabolism in sheep and roe deer. Selenium deficiency was diagnosed in liver samples of both sheep flocks (0.21 and 0.23 mg/kg ww). There were neither significant differences compared to roe deer (0.21 and 0.27 mg Se/kg ww) nor differences depending on location. Correlations between plasma and liver concentrations of Cu, Zn and Se were not significant in sheep. Means of vitamin E in liver samples (30.6 and 41.8 mg/kg ww) were higher in roe deer populations. This may be caused by the opportunity of selective browsing for wild ruminants, which allows access to younger plants which are higher in vitamin E.  相似文献   

7.
Despite the importance of roe deer as a host for Ixodes ticks in central Europe, estimates of total tick burden on roe deer are not available to date. We aimed at providing (1) estimates of life stage and sex specific (larvae, nymphs, males and females, hereafter referred to as tick life stages) total Ixodes burden and (2) equations which can be used to predict the total life stage burden by counting the life stage on a selected body area. Within a period of 1½ years, we conducted whole body counts of ticks from 80 hunter-killed roe deer originating from a beech dominated forest area in central Germany. Averaged over the entire study period (winter 2007–summer 2009), the mean tick burden per roe deer was 64.5 (SE ± 10.6). Nymphs were the most numerous tick life stage per roe deer (23.9 ± 3.2), followed by females (21.4 ± 3.5), larvae (10.8 ± 4.2) and males (8.4 ± 1.5). The individual tick burden was highly aggregated (k = 0.46); levels of aggregation were highest in larvae (k = 0.08), followed by males (k = 0.40), females (k = 0.49) and nymphs (k = 0.71). To predict total life stage specific burdens based on counts on selected body parts, we provide linear equations. For estimating larvae abundance on the entire roe deer, counts can be restricted to the front legs. Tick counts restricted to the head are sufficient to estimate total nymph burden and counts on the neck are appropriate for estimating adult ticks (females and males). In order to estimate the combined tick burden, tick counts on the head can be used for extrapolation. The presented linear models are highly significant and explain 84.1, 77.3, 90.5, 91.3, and 65.3% (adjusted R 2) of the observed variance, respectively. Thus, these models offer a robust basis for rapid tick abundance assessment. This can be useful for studies aiming at estimating effects of abiotic and biotic factors on tick abundance, modelling tick population dynamics, modelling tick-borne pathogen transmission dynamics or assessing the efficacy of acaricides.  相似文献   

8.
Roe deer (Capreolus capreolus) has a wide distributional range in Europe and inhabits a broad range of habitats and environmental conditions. Thus, populations of roe deer show substantial variation in demographic parameters. We aimed to determine whether body mass and population density—which influence the reproductive potential of roe deer at a local scale—affect their reproductive potential at a biogeographical scale as well. We reviewed the literature (covering years 1948–2015) on in utero litter size in roe deer from 59 locations in 14 countries in Europe. Across study sites, mean litter size varied from 1.0 to 2.4 embryo or corpora lutea per female, and population density ranged from 4.5 to 73.5 individuals/km2. Mean body mass varied from 11.2 to 20.8 kg in subadult females and from 12.1 to 22.4 kg in adult females. Between 46° and 56° N, body mass of females did not show a significant trend of increase, whereas between 56° and 63° N, it increased with latitude (Bergmann’s rule). We used linear mixed-effects models (LMMs) to analyse the influence of body mass and population density (analysed separately) on litter size. Females with larger body mass produced larger litters, and this pattern was pronounced at both higher and lower latitudes. Higher population densities negatively affected litter size in a sample of all females. This macroecological analysis showed that factors influencing the reproductive potential of roe deer females at local scales produce similar effects at the biogeographical scale.  相似文献   

9.
The aim of present study was to assess the correlation between the method of treating the carcasses of shot wild ducks (Anas platyrhynchos) and the formation of biogenic amines in the their muscles. The carcasses of wild ducks (n?=?180) were divided into three groups of 60 carcasses according to the method of treatment: eviscerated, drawn, and left untreated. Each group was further divided into three subgroups of 20 duck carcasses on the basis of the storage temperature (0, 7, and 15 °C) and stored for 21 days. Samples of breast and thigh muscles were taken at regular weekly intervals. Biogenic amines (cadaverine, putrescine, tyramine, histamine, phenylethylamine, and tryptamine) in samples of breast and thigh muscles were separated by reverse-phase liquid chromatography and detected by tandem mass spectrometry. The sum of biogenic amines was compared with a value of 5 mg/kg, indicating the critical content for fresh meat of high hygienic quality. The results of this study indicated that the sum of biogenic amines in wild duck meat exceeded this limit in an extremely short period of time after the commencement of storage (during the first week of storage). Higher content of biogenic amines were recorded in thigh muscle compared to breast muscle of drawn ducks and untreated ducks. According to our results, the generally recommended method for treating the carcasses of feathered game after hunting (evisceration) does not represent a method that would ensure a longer period of freshness or higher hygiene quality of the game than the other two possible methods of treatment from the biogenic amines point of view.  相似文献   

10.
BackgroundDue to excellent nutritional properties of fish and fish products, dietitians recommend their larger share in the diet, for both the prevention and treatment of diet-related diseases. In this context particular attention should be given to fish eggs (roe). The aim of the study was to compare the content of selected minerals and trace elements in the roe and muscle tissue of aquaculture-reared rainbow trout. Moreover, the extent to which an edible portion of 100 g of fish product (roe or fillet) satisfies the requirements for these elements in adult consumers (women and men) and children was determined.MethodsThe research material was represented by 20 farmed rainbow trout females (Oncorhynchus mykiss). In muscle tissue and roe the proximate composition, energy value, and nutritional quality index were examined. Concentrations of K, Na, Ca, Mg, Zn, Fe, Mn and Cu were determined by flame atomic absorption spectrometry analysis. The levels of minerals and trace elements in fish products were used to calculate the percentages of the recommended dietary reference values for adults and children in portion of 100 g.ResultsThe roe had higher content of 7 elements including, Zn (29.40 ± 1.38, 27.74–30.91 mg/kg), Mn (1.66 ± 0.08, 1.55–1.73 mg/kg), Fe (11.17 ± 0.35, 10.75–11.60 mg/kg), Cu (1.24 ± 0.04, 1.21–1.30 mg/kg), Ca (546.90 ± 23.68, 522.02–578.96 mg/kg), Mg (546.97 ± 23.68, 522.02–578.96 mg/kg), Na (403.61 ± 5.53, 397.29–407.57 mg/kg) compared to muscle tissue, respectively, Zn (2.73 ± 0.97, 0.94–3.77 mg/kg, Mn (0.22 ± 0.10, 0.14–0.46 mg/kg), Fe (2.19 ± 1.44, 1.02–5.50 mg/kg), Cu (0.24 ± 0.06, 0.17–0.36 mg/kg), Ca (164.07 ± 71.72, 93.24–306.32 mg/kg), Mg (240.00 ± 73.37, 127.92–316.41 mg/kg), Na (273.37 ± 99.65, 183.93–524.41 mg/kg). In turn, the muscle tissue contained 3 times as much K (5159.87 ± 974.70, 4004.63–6343.91 mg/kg) as the roe (1713.65 ± 58.68, 1643.97–1764.14 mg/kg). The roe covered the recommended nutrition standards (population reference intake, PRI and adequate intake, AI) to a greater extent than the fillet for all analysed trace elements and minerals except K. For children, the contribution of roe to the reference intake of such elements as Mg, Zn, Fe, Mn and Cu was particularly high. Therefore the roe should be considered as a source of Mg for all consumer groups, and as high in Zn for women and children. The suggested portion of fillet and roe provided only 2–3 % of the daily requirement for Na.ConclusionsDespite the differences found, both roe and fillet from rainbow trout are a good source of analysed elements. The results indicate the need to continue research in order to determine the influence of other factors on the content of minerals and trace elements in roe and the possibility of using gonads to enrich other food products with elements.  相似文献   

11.
After a decline in the early 19th century, a remnant population of the Scandinavian roe deer (Capreolus capreolus) was protected in southern Sweden around 1840. The roe deer quickly recovered and recolonized most of the Scandinavian Peninsula. In this study, I analyze microsatellite variation in 14 roe deer populations in Scandinavia to (1) investigate if all Swedish roe deer trace their ancestry to southern Sweden, (2) define other areas where roe deer may have remained during the population decline, and (3) examine if the large geographic distances during the expansion phase have influenced the degree and sorting of genetic variation. The results show that the mainland roe deer most likely trace their ancestry to southern Sweden, but interestingly, the two neighboring populations Övedskloster and Wittskövle in the south are significantly different from each other (p<0.01). Furthermore, the population in Wittskövle and roe deer from Köpingsvik at the Baltic Sea Island Öland are significantly different from all other populations (p<0.1). Thus, potentially, there are more than one founder population that contributed to the current Swedish population. The particular differentiation of roe deer from Öland might be an effect of random population genetic processes during the population expansion phase, potentially in combination with introductions of roe deer from other areas than the Swedish mainland. The results are discussed in relation to management of roe deer in Sweden.  相似文献   

12.
Tracking devices are commonly used to locate and monitor wild animals for studying spatial ecology and survival rates. There is growing interest in capture effects, partially to minimize the impact on the study species, but also for animal welfare reasons. This study aims to examine roe deer behaviour in box-traps, when restrained, when released and during recaptures to quantify injuries and deaths over a period of 41 years. We use data from 2911 captures from 926 individuals between 1973 and 2014. We recorded behaviour inside the box-traps over two seasons. We also recorded behavioural data from 671 catches of 346 individuals during six seasons to study habituation. Additionally, we discuss box-traps in relation to ethological theory and animal welfare. Over a 41-year period, one roe deer suffering from starvation was found dead in a trap (0.035%), which cannot be solely related to capture (N = 926). About 58% of all roe deer were recaptured at least once during their life time. There was a low prevalence of injuries (0.5% of the captures, N = 2911), and they occurred predominately to the nose or antlers in velvet (in males). During the first hour after capture, animals typically stand very tense between eating bouts. Thereafter, the deer tended to move more softly and exhibited resting behaviours (e.g. lying down). Overall, we conclude that this method of capture and handling had very low impact on the welfare or survival of roe deer, which also habituated to recapture over successive events.  相似文献   

13.

Background

Lead-free hunting bullets are an alternative to lead-containing bullets which cause health risks for humans and endangered scavenging raptors through lead ingestion. However, doubts concerning the effectiveness of lead-free hunting bullets hinder the wide-spread acceptance in the hunting and wildlife management community.

Methods

We performed terminal ballistic experiments under standardized conditions with ballistic soap as surrogate for game animal tissue to characterize dimensionally stable, partially fragmenting, and deforming lead-free bullets and one commonly used lead-containing bullet. The permanent cavities created in soap blocks are used as a measure for the potential wound damage. The soap blocks were imaged using computed tomography to assess the volume and shape of the cavity and the number of fragments. Shots were performed at different impact speeds, covering a realistic shooting range. Using 3D image segmentation, cavity volume, metal fragment count, deflection angle, and depth of maximum damage were determined. Shots were repeated to investigate the reproducibility of ballistic soap experiments.

Results

All bullets showed an increasing cavity volume with increasing deposited energy. The dimensionally stable and fragmenting lead-free bullets achieved a constant conversion ratio while the deforming copper and lead-containing bullets showed a ratio, which increases linearly with the total deposited energy. The lead-containing bullet created hundreds of fragments and significantly more fragments than the lead-free bullets. The deflection angle was significantly higher for the dimensionally stable bullet due to its tumbling behavior and was similarly low for the other bullets. The deforming bullets achieved higher reproducibility than the fragmenting and dimensionally stable bullets.

Conclusion

The deforming lead-free bullet closely resembled the deforming lead-containing bullet in terms of energy conversion, deflection angle, cavity shape, and reproducibility, showing that similar terminal ballistic behavior can be achieved. Furthermore, the volumetric image processing allowed superior analysis compared to methods that involve cutting of the soap blocks.  相似文献   

14.
Rarely found infected, roe deer (Capreolus capreolus) are not considered a bovine tuberculosis (bTB) reservoir. However, serial cases discovered between 2010 and 2014 in one of the bTB endemic regions in France threw doubt on the epidemiological role played by this small wild cervid in ecosystems where cattle and other wild animals are both infected. Our objective was to analyse the bTB host status of roe deer as regards infection prevalence within the population and Mycobacterium bovis-induced pathology in this species. From November 2001 to March 2016, 668 roe deer were analysed (culture and/or PCR) through active surveillance implemented in three bTB endemic areas in France (Brotonne forest, Dordogne and Côte d’Or) and 132 through passive surveillance (presence of macroscopic lesions) in the whole country. Only seven roe deer were found infected by M. bovis, exclusively in bTB endemic areas, one through active surveillance (Brotonne forest; n = 203, apparent prevalence 0.49%). On the basis of these results, observed pathological patterns (mainly pulmonary lesions), species social behaviour (less gregarious than other ungulates) and food behaviour (mainly a selective browser), roe deer does not appear to be a true reservoir of bTB. However, once infected, it develops lesions reflecting a clear ability for bacterial excretion and therefore transmission to other species, most likely by indirect contact. It could thus be a spillover host included in a multi-host component reservoir in endemic areas. Consequently, passive surveillance is essential to detect infection and to implement specific management to limit interactions with cattle, where infected roe deer are found.  相似文献   

15.
Sika deer (Cervus nippon) suffer severe winter food limitation in northern Japan; however, plant food resources are available during winter in southern Japan and, consequently, deer nutritional status may not decrease there. To test this hypothesis, we measured seasonal changes in Riney’s kidney fat index (RKFI) and stomach intake in 74 culled deer individuals from five areas with different deer densities on Yakushima Island, Japan. The average RKFI differed significantly among populations and ranged from 22.91 ± 11.91 to 76.23 ± 15.99. There was no significant correlation between RKFI and deer density. The total fresh weight of rumen contents also differed significantly among populations, ranging from 0.51 to 3.51 kg. Food intake and RKFI exhibited an L-shaped distribution in the vicinity of a town ranch. However, we found that food intake had a significantly positive effect in populations at the other four locations, suggesting that changes in nutritional status were related to the quantity of deer rumen contents. Neither deer density nor season were significantly correlated with RKFI values. The average RKFI values exceeded 20 in all five locations. These findings indicate that the deer were not in a poor nutritional condition even in high density areas of >70 head/km2, which supports the above hypothesis. Notably, food intake varied among individuals in the same area, but was independent of body weight and age, which suggests that food selectivity differs between deer individuals.  相似文献   

16.

Background

The extant roe deer (Capreolus Gray, 1821) includes two species: the European roe deer (C. capreolus) and the Siberian roe deer (C. pygargus) that are distinguished by morphological and karyotypical differences. The Siberian roe deer occupies a vast area of Asia and is considerably less studied than the European roe deer. Modern systematics of the Siberian roe deer remain controversial with 4 morphological subspecies. Roe deer fossilized bones are quite abundant in Denisova cave (Altai Mountains, South Siberia), where dozens of both extant and extinct mammalian species from modern Holocene to Middle Pleistocene have been retrieved.

Methodology/Principal Findings

We analyzed a 629 bp fragment of the mitochondrial control region from ancient bones of 10 Holocene and four Pleistocene Siberian roe deer from Denisova cave as well as 37 modern specimen belonging to populations from Altai, Tian Shan (Kyrgyzstan), Yakutia, Novosibirsk region and the Russian Far East. Genealogical reconstructions indicated that most Holocene haplotypes were probably ancestral for modern roe deer populations of Western Siberia and Tian Shan. One of the Pleistocene haplotypes was possibly ancestral for modern Yakutian populations, and two extinct Pleistocene haplotypes were close to modern roe deer from Tian Shan and Yakutia. Most modern geographical populations (except for West Siberian Plains) are heterogeneous and there is some tentative evidence for structure. However, we did not find any distinct phylogenetic signal characterizing particular subspecies in either modern or ancient samples.

Conclusion/Significance

Analysis of mitochondrial DNA from both ancient and modern samples of Siberian roe deer shed new light on understanding the evolutionary history of roe deer. Our data indicate that during the last 50,000 years multiple replacements of populations of the Siberian roe deer took place in the Altai Mountains correlating with climatic changes. The Siberian roe deer represent a complex and heterogeneous species with high migration rates and without evident subspecies structure. Low genetic diversity of the West Siberian Plain population indicates a recent bottleneck or founder effect.  相似文献   

17.
Most roe deer females produce twins and more rarely singletons and triplets. Some very rare reported cases of litters above three offspring refer to quadruplets which are, however, very much an exception in roe deer reproduction (only some tens of documented cases can be found in the scientific literature). In this paper, we present the first firm evidence that roe deer females are able to produce even five offspring. By examination of large sample set (n = 4690) of roe deer uteri and ovaries in two neighbouring countries in southern/central Europe (Italy and Slovenia), we found ten females that either carried or had potential to produce quadruplets, and in three does the (potential) litter size was even five. While one doe from Slovenia had five corpora lutea, two does from Tuscany, Italy, carried five foetuses. In both cases, all foetuses were normally and equally developed, indicating that none of them had predominant exposure to resorption/abortion. Six out of 13 females with exceptionally large potential litters (>3 offspring) had significantly higher body mass in comparison with mean body mass of all does harvested in the same hunting management district and in the same period, while five of them were significantly lighter. This indicates that some roe deer females can produce exceptionally large litters even when their phenotypic quality is not higher than the average in the population, and that such large litters are a stochastic episode rather than a reproductive performance of a very vital individual(s).  相似文献   

18.
Five mouflon [average body mass (BM) 33 kg] and two roe deer (average BM 20 kg) with rumen cannulas were kept in large enclosures under semi-natural conditions and were used for seasonal studies on gastrointestinal tract (GIT) indigestible fill and digesta passage kinetics. As the mouflon were not fully mature, both species had similar digesta volumes in the reticulorumen (RR; mouflon 5.5 ± 1.8% of BM; roe deer 5.4 ± 1.5% of BM); however, the mouflon had lower RR liquid flow rates (15.1 ± 4.3 ml h−1 kg−0.75) than the roe deer (19.2 ± 0.2 ml h−1 kg−0.75), and particle retention in the RR accounted for 68 ± 3% of total GIT retention in the mouflon versus 55 ± 6% in the roe deer. Annual average total GIT retention times for liquids and particles were longer in the mouflon (23.4 ± 0.9 h and 37.9 ± 4.0 h) than in the roe deer (18.4 ± 1.7 h and 22.4 ± 1.9 h). Similarly, annual average RR retention times for liquids and particles were longer in the mouflon (11.9 ± 0.9 h and 25.8 ± 3.3 h) than in the roe deer (8.1 ± 1.7 h and 12.5 ± 2.3 h). The factor of selective particle retention in the RR (retention of particles/retention of liquid) was 2.10 ± 0.09 in the mouflon versus 1.54 ± 0.01 in the roe deer. These observations are in accord with differences in digesta passage characteristics postulated between browsing and grazing ruminants. Total GIT indigestible fill was lower in the mouflon than in the roe deer (10.7 ± 2.1 g kg−1 and 13.3 ± 1.0 g kg−1).  相似文献   

19.
2009年12月到2010年1月,在黄泥河自然保护区采用样线法对狍冬季卧息地选择进行研究.在研究中共设置了47条样线,调查了72个狍利用样方和109个对照样方,评价了15类生态因子对狍冬季卧息地选择的影响.研究结果表明:在黄泥河自然保护区冬季,狍在卧息时喜欢选择平均海拔在591 m,位于阳坡中坡位上雪被较浅、食物丰富度、灌丛盖度、郁闭度和隐蔽水平都较高的针阔混交林生境,尤其喜欢在针阔混交林中的针叶树下卧息,避开选择阴坡、针叶林和裸岩.逻辑斯蒂回归分析结果表明:食物丰富度、针叶树、雪深、裸岩和海拔是影响黄泥河自然保护区冬季狍卧息地选择的主导因子,林型、坡向和隐蔽水平是次要因子.由这7个变量组成的回归模型为:Z=32.628+11.675×坡向(1) +9.741×坡向(2)-5.486×林型(1)-7.933×林型(2)-7.496×裸岩(1)-9.906×针叶树(1)-0.043×海拔+0.170×隐蔽水平+0.220×食物丰富度-0.429×雪深.模型选择利用概率为P(z)=ez/1+ez,整体正确预测率为96.1%.  相似文献   

20.
To evaluate the influence of breed on the accumulation of dietary copper (Cu) in tissue, and on blood parameters indicative of Cu status, ten Galician Blond, nine Holstein-Friesian and ten Galician Blond × Holstein-Friesian cross (GB × HF) steers were fed diets supplemented with 35 mg/kg DM of CuSO4 during their growing and finishing periods. Blood samples were taken monthly, and samples of liver, kidney, brain, heart, spleen and muscle were taken at slaughter. Cu concentrations were determined by ICP-AES. Holstein-Friesian calves had significantly higher total liver Cu contents than Galician Blonds and GB × HF crosses (mean 1070, 663 and 868 mg, respectively), combined with higher hepatic Cu concentrations (174, 140 and 166 mg/kg wet weight, respectively). Holstein-Friesian calves had also the highest prevalence (89%) of hepatic Cu concentrations exceeding the toxic limit of 150 mg/kg wet weight. Breed did not have a statistically significant influence on blood parameters. With the exception of the semitendinosus muscle, where Holstein-Friesians (0.790 mg/kg) had significantly higher Cu levels than Galician Blonds (0.541 mg/kg) or GB × HF crosses (0.631 mg/kg), no other statistically significant differences by breed in the extrahepatic tissue Cu distribution were observed. A negative statistical association between carcass performance and the ratio of semitendinosus and liver Cu concentration could indicate that the animals with a better carcass performance (Galician Blonds) could need a higher Cu mobilisation into the muscle, resulting in a lower hepatic storage.  相似文献   

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