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1,996 result(s) for "Ovis aries"
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Genomic signatures of adaptive introgression from European mouflon into domestic sheep
Mouflon ( Ovis aries musimon ) became extinct from mainland Europe after the Neolithic, but remnant populations from the Mediterranean islands of Corsica and Sardinia have been used for reintroductions across Europe since the 19 th -century. Mouflon x sheep hybrids are larger-bodied than mouflon, potentially showing increased male reproductive success, but little is known about genomic levels of admixture, or about the adaptive significance of introgression between resident mouflon and local sheep breeds. Here we analysed Ovine medium-density SNP array genotypes of 92 mouflon from six geographic regions, along with data from 330 individuals of 16 domestic sheep breeds. We found lower levels of genetic diversity in mouflon than in domestic sheep, consistent with past bottlenecks in mouflon. Introgression signals were bidirectional and affected most mouflon and sheep populations, being strongest in one Sardinian mouflon population. Developing and using a novel approach to identify chromosomal regions with consistent introgression signals, we infer adaptive introgression from mouflon to domestic sheep related to immunity mechanisms, but not in the opposite direction. Further, we infer that Soay and Sarda sheep carry introgressed mouflon alleles involved in bitter taste perception and/or innate immunity. Our results illustrate the potential for adaptive introgression even among recently diverged populations.
Influences of Domestication and Island Evolution on Dental Growth in Sheep
Domestication and island evolution can lead to changes of life history along the slow-fast gradient. Shifts of life history patterns, in turn, are potentially related to alterations of patterns and timing of tooth eruption. Schultz’s rule predicts an earlier eruption of molars relative to premolars as fecundity increases during the domestication process. On the other hand, evolution on a predator-free, resource limited island might lead to a generally slow life history and delayed tooth eruption, as in the Plio-Pleistocene Balearic caprine Myotragus . In this study, we investigate tooth eruption and its relation to life history in a unique sheep population that is an example of both domestication and island evolution: the ancient and feral Soay sheep ( Ovis aries ) of the St. Kilda archipelago, Scotland. Tooth eruption timing and sequence is investigated in a comparative framework featuring new data on other domestic sheep ( O. aries ), including European mouflon ( O. a. musimon ), as well as wild sheep ( O. vignei , O. cycloceros , O. arkal , O. orientalis , O. ammon ). These data indicate that the order of eruption is similar in wild and domestic sheep, despite the fundamental life history changes that came about with domestication. However, in contrast to other domestic sheep breeds, Soay sheep erupt their teeth at an absolute older age and also tend to grow more slowly, which resembles the evolutionary trend in island-adapted Myotragus . Despite these similarities, Soay sheep do not share the slow life history pattern inferred for Myotragus , highlighting the distinctive nature of tooth eruption in Soay sheep.
Do sheep (Ovis aries) discriminate human emotional odors?
While sheep can detect and discriminate human emotions through visual and vocal cues, their reaction to human body odors remains unknown. The present study aimed to determine whether sheep ( Ovis aries ) can detect human odors, olfactorily discriminate stressed from non-stressed individuals, and behave accordingly based on the emotional valence of the odors. Axillary secretions from 34 students were collected following an oral examination (stress odor) or a regular class (non-stress odor). Fourteen female and 15 male lambs were then exposed to these odors through a habituation-dishabituation procedure. The habituation stimulus was presented four times for one minute, followed by the dishabituation stimulus presented once for one minute. Behavioral variables included spatiality relative to target odors, approach/withdrawal, ear positioning, sniffing, ingestion, and vocalization. Both female and male lambs more often positioned their ears backwards/forwards, and asymmetrically when exposed to the dishabituation stimulus, but regardless of their stress or non-stress value. They also changed their approach behavior when exposed to the dishabituation stimuli. Lambs displayed some behavioral signs of discrimination between the habituation and dishabituation odors, but regardless of their relation to stress or non-stress of human donors. In sum, this exploratory study suggests that young sheep respond negatively to the odor of unfamiliar humans, without showing any specific emotional contagion related to the stress odor. This exploratory study suggests young ovines can detect human body odor, a further step toward understanding the human-sheep relationship.
Isolation and Purification of Protein from Ovis aries Placenta
The total protein extract of sheep placenta was fractionated by tandem anion-exchange chromatography over Toyopearl DEAE-650M and gel filtration over Toyopearl HW-55F. The obtained homogeneous protein exhibited antiproliferative activity in HeLa and HCT-116 cell culture (IC 50 0.80 ± 0.27 and 1.73 ± 0.03 mg/mL, respectively). The amino-acid composition of the purified protein was determined. Tandem mass spectral sequencing and subsequent annotation using a database identified the purified protein as a calponin homolog.
Does predation risk affect spatial use in an introduced ungulate species? The case of a Mediterranean mouflon alpine colony
Predation risk is known to affect the spatial use of prey species, imposing a trade-off between feeding requirements and predation avoidance. As a result, prey species can leave high-quality forage areas to use sub-optimal, but safer, habitat patches, defined as “refuge areas.” In this study, we describe changes in the spatial use of an introduced ungulate species, the Mediterranean mouflon Ovis aries musimon, following the recolonization (in 1996) of wolves Canis lupus into the Albergian Hunting Estate (Italian Western Alps). Since 1988, we monitored the mouflon population by spring counts from vantage points. We georeferenced all observations and recorded the size and structure of the spotted groups. Finally, we identified available refuges by selecting patches characterized by (i) the presence of rocks and (ii) high values of steepness and ruggedness. We found that mouflons significantly reduced the average distance from refuge areas over the years, with the yearly average distance from refuges being 56% lower after wolves recolonized the area (i.e., 93.8 ± 32.1 vs. 213.1 ± 40.9 m). The analysis of orographic parameters showed that mouflons used patches with higher values in elevation, slope, ruggedness, and a significant difference in all three parameters when comparing years pre and post wolf return. Both sexes were significantly affected, but ewes were particularly sensitive and selected patches closer to refuge areas (75.8 ± 30.3 m) than males (131.0 ± 53.6 m). Our results suggest that the presence of new predators can alter the distribution of an introduced species such as the Mediterranean mouflon, triggering the resurgence of anti-predation behavior.
Morphometric analysis of the skulls of a ram and ewe Romanov sheep (Ovis aries) with 3D modelling
Background With the development of technology, 2D images have left their place for 3D models. The 3D modelling technique is widely used in plastic surgery, orthopaedic surgery, neurosurgery, traumatology, dentistry and medical education. The skull is important in terms of containing the starting parts of systems with vital functions. Objective The aim of the study is to reveal the difference between male and female and other species by 3D (three‐dimensional) modelling and craniometric measurements of Romanov heads. Methods In our study, skulls of Romanov sheep (10 females and 10 males) older than 1‐year‐old were used. The heads of Romanov sheep were scanned with computed tomography and modelled in 3D. Results and Conclusions In the study, it was determined that there was a statistically significant difference between male and female sheep in terms of the largest nose length, facial width, molar row length, viscerocranium length, and foramen magnum height parameters (p < 0.05). It was determined that the greatest width of the foramen magnum measurement parameter and the skull index showed statistically significant differences between the genders at the p < 0.01 level. No statistically significant difference was found in other measurements (p > 0.05). The data obtained as a result of the study will help in the racial discrimination and classification of bones obtained from zoo archaeological excavations. This study is to reveal the difference of the measurements taken from the determined points by creating a 3D model of Romanov sheep from other species. It was determined that there was a statistically significant difference between males and females in the measurements of the greatest length of nasals, facial breadth, length of the molar row, viscerocranium length and height of the foramen magnum. It has been revealed that the anatomical structures in the skull are different compared to other sheep species.
The relationship between G1 (c.260 G>A) and G4 (c.721 G>A) polymorphisms in the GDF9 gene and the litter size of sheep: A meta-analysis study
Objective: The results of G1 and G4 polymorphisms as litter-size (LS) markers of ewes remain contradictory. The aim was to evaluate the impact of G1 (c.260 G>A) and G4 (c.721 G>A) polymorphisms on the LS of sheep by synthesizing data from multiple previous studies. Methods: Data were extracted from 14 eligible articles. The genotypes of G1 and G4 polymorphisms were homozygous wild-type (WW), heterozygous (WM), and homozygous mutanttype (MM). The standardized mean difference (SMD) method using random effect models was employed to determine the effect size of G1 and G4 polymorphisms on LS under dominant, recessive, additive, and co-dominant genetic models. Heterogeneity was analyzed with the I2 statistic index. Publication bias was depicted with funnel plots and tested by Egger’s and Begg’s tests. Results: The study showed that the correlation between G1 polymorphism and LS in sheep was not significant (p > 0.05) under all genetic models. The influence of G4 polymorphism on the LS of sheep was found significantly (p < 0.05) under dominant [SMD = 0.28, I2 = 0% (no heterogeneity)] and co-dominant [SMD = −0.14, I2 = 36% (moderate heterogeneity)] genetic models. The WM genotype of G4 polymorphism increased LS, while the MM genotype reduced LS in sheep. Publication bias among G1 and G4 polymorphism studies was absent in all genetic models. Conclusion: Thus, the study revealed that G4 polymorphism could be a potential genetic marker for LS in ewes. On the contrary, G1 polymorphism has no association with the LS of ewes.
A New Species of Demodex (Acariformes: Prostigmata) Observed in the Mouflon, Ovis aries musimon (Artiodactyla: Bovidae) with Data on the Parasitism and Occurrence of Other Ectoparasites
A greater understanding of mite biodiversity and ecology can explain their preference for microhabitats within host bodies, i.e., as ecto-, meso-, and endoparasites. Similarly, learning about the patterns formed by mite communities in wild animals can shed light on the mechanisms of parasitosis development in their domesticated counterparts. Hence, the present study examined the acarofauna of the mouflon, introduced to Poland in the early 20th century from a region of endemic occurrence. Forty-one individuals were examined for the presence of ectoparasites between 2010 and 2013; later, skin fragments were analysed for the presence of skin mites. A new species of Demodecidae, Demodex musimonis sp. nov., was discovered in the skin of the pasterns of 14.6% mouflons, as well as the ectoparasitic tick Ixodes ricinus (prevalence 29.3%) and ungulate-typical fly Lipoptena cervi (34.1%). However, no mites typical for ovine Ovis (Psorergatidae, Psoroptidae) were noted, nor any colonisation of microhabitats by species from local ungulates, resulting from the loss of original parasites during the introduction. A comparison of the acarofauna of the mouflon and domestic sheep Ovis aries aries suggests that a mite community with a complex structure and the co-occurrence of different families may be formed. However, it is not known whether the acarofauna of domestic sheep is derived from wild ancestors or the process of domestication. Even so, the peculiar Demodecidae must have been part of the natural parasitofauna of wild sheep, of which only D. musimonis sp. nov. has been recognised so far.
Livestock displace European mouflon from optimal foraging sites
The conflict between free-ranging livestock and wildlife is a serious conservation concern across rural communities worldwide. Livestock may affect wild herbivores via direct competition for resources due to spatial and diet overlap or via behavioural interference. It is imperative that we disentangle the effects of livestock on wildlife behaviour to obtain an empirical basis able to stir management and conservation decisions. Here, we studied the effect of livestock presence on the habitat selection in a free-ranging European mouflon (Ovis aries musimon) population in Sardinia, where the species is under strict protection. We collected spatial data on mouflon and livestock during two consecutive years to investigate whether the mouflon selection of key feeding grassland sites was negatively impacted by the livestock presence. We found that mouflon preferably selected grassland, and its selection significantly increased when grass was of better quality (greener). We showed that livestock presence led to the displacement of mouflon from such preferred feeding sites, an effect clearly exacerbated by livestock proximity. We indeed found that the selection of grassland by mouflon dropped significantly when the distance between livestock and mouflon was below ~ 650 m, providing a useful management threshold indication. Livestock presence in close proximity displaced mouflon to sub-optimal habitat, and its effects may have negative impact on the population dynamic of this species which is already characterized by low female productivity within harsh Mediterranean environment. Our results give clear management indications aimed at better managing livestock grazing within natural areas to ultimately improve wildlife conservation.
Exogenous enzymes in sheep diet: nutritional and physiological parameters
The objective of this study was to evaluate the effect of adding exogenous enzymes to the diet on nutrient intake and digestibility, nitrogen balance, ingestive behavior and rumen movement of ewe lambs. Five ewe lambs, Dorper x Santa Inês crossbred, with an average age of 7 ± 1 months, average weight of 36.40 ± 2.36 kg were assigned in a 5x5 Latin square design. The treatments consisted of adding exogenous enzymes to the concentrate: Allzyme, Fibrozyme®, Amaize®, Mix and Control. Analyses of variance were applied and means were compared by the SNK test, and non-parametric Kruskal Wallis test at 5% significance. The dry matter intake in relation to body weight, crude protein intake and nitrogen intake were higher with the use of amylolytic enzyme compared to the other treatments (p <0.05). Nitrogen balance was higher with the use of amylolytic enzymes and the Allzyme® enzyme complex (p <0.05). A longer time spent in total chewing was observed with the inclusion of fibrolytic and amylolytic enzymes without changes in rumen movement. The use of exogenous enzymes promotes better use of nutrients, with high digestibility of dry matter, neutral detergent fiber and crude protein.