Sheep Horn Research Articles

How Do Scientists Know? Answering High School Students’ Questions with an Ecological Sampling Unit

What do animals eat? What animals are present in a habitat? How many animals are present? How was the habitat different years ago? How old is this animal? These are all questions that scientists want to answer. We know the answers to questions like these from data collected by scientists in a variety of ways. Science is evidence based, and conclusions are arrived at after multiple replicable experiments. Presented here are six ecological scenarios that demonstrate how scientists arrive at answers to population ecology questions. These lessons can be implemented as single activities that supplement a high school ecology or environmental science curricular unit or as a multiday rotation of stations in which students practice field sampling techniques used in population and community ecology, designed to answer ecological questions. Student scientists learn how to use indirect sampling methods to estimate abundance, density, age, and population size using mark–recapture, transects, and quadrats to model authentic field methods. They calculate species richness and biodiversity with a simplified Simpson’s diversity index and describe species age structure and distribution using tree rings, sheep horns, and camera trap images. Students also learn to display population data appropriately, graphing survivorship and richness vs. area and studying trophic pyramids.

Progress on genetic mapping and genetic mechanism of cattle and sheep horns.

Horns are cranial appendages, which are unique in ruminants. Cattle (Bos taurus) and sheep (Ovis aries) cranial appendages exhibit various forms of morphology, including wild-type two-horn phenotype, polled phenotype and scur phenotype. These animals provide an ideal model for studies on the underlying relationship between quality and quantitative traits of cattle and sheep horn and the molecular mechanisms of horn phenotype as a polygenic regulation for quality traits. In recent years, some research progresses of cattle and sheep horns are successively reported, which helps us better understand the evolutionary origin of new organ, the effects of natural selection, sex selection and artificial selection on horn phenotypes. In this review, we introduce in details the recent advances on the research of horn traits in cattle and sheep, and summarize the genetic mapping of multi-horned phenotypes, the genetic mapping of polled locus, and studies on scur phenotype. Moreover, we discuss potential problems in such research, thereby providing a reference for investigation on the genetic mechanisms of horn traits in ruminants.

Morphological and microscopical studies and Phytochemical analysis of Markhamia falcata (Seem)

Markhamia falcata (Seem) synonym Dolichondron falcata is belonging to family BIGNONIACEAE. Markhamia falcata commonly known as ‘Medhshing’ in hindi, ‘mesasinghi’ in Sanskrit (means look like sheep horn, showing in plate.) Markhamia falcata native to Malawi, Tanzania, South Africa, and India. In India it is found in Rajputana, Bundelkhand, Bihar, Deccan, Mysore, most forests of Madras Presidency. It is also planted as ornamental plant in Gardens. The plant Markhamia falcata (Seem) (Syn. Dolichandrone falcata) has been used mainly for diabetics, antioxidant, anti-inflammatory, anti-cancer, antiesterogenic and for anxiolytic activities. The leaves are also used in the treatment of leucorrhea, body aches, abortion piles etc. Markhamia falcata contain chemical constituents such as alkaloids, flavonoids, sugars, saponin, amino acids, phenolic group etc. There are many medicinal plants for which limited phytochemical studies have been carried out and hence intensive efforts are required in this direction. Phyto-chemical quality of any herbal remedy is ensured by identification of biological compound present in it. Keeping this thought in mind, the present study was conducted in order to discover the qualitative and quantitative nature of leaves, and bark Markkhamia falcata. Since there is no proper information regarding histological character of this plant our efforts were devoted to study the pharmacognostical properties of this plant.

Review on Production Systems, Farmers Trait Preferences and Breeding Practice of Indigenous Sheep Breeds in Ethiopia

In Ethiopia sheep serve as a source of income, meat, milk, skin, manure and employment for smallholder rural farmers. Sheep are the most preferred animals by rural poor communities as they require small investment, have shorter production cycles faster growth rates and greater environmental adaptability as compare to large ruminant. The objective of this senior seminar is reviewing on Production Systems, Selection criteria and Breeding practice of indigenous Sheep Breeds in Ethiopia. Rural households are practicing animal husbandry in diverse production systems and climatic zone which are classified as three major different production systems; highland sheep-barely, mixed crop-livestock and pastoral and agro-pastoral production systems. However, sheep production and productivity in the country is challenged by scarcity of feed, diseases outbreak, poor infrastructure, lack of market information, lack of knowledge, absence of planned breeding programs and policies. The existed sheep type in the country is really the output of human intervention and natural selection. Traits like coat color, tail type, horn and ear size of sheep can also have dynamic effect on the price of sheep marketing. For selecting breeding ram’s farmers consider different traits like body conformation, coat color, tail type/size, growth rate, sexual drives, dentation and the quality of being adapted and record of ancestors. Breeding ewes are selected by farmers as a replacement stock based on their Coat color, twining ability, lamb growth, lamb survival, age at first lambing and lambing intervals. In Ethiopia the main objective of sheep production is to provide income, meat, milk, skin, manure and employment for smallholder rural farmers. In Ethiopia both pure-breeding and crossbreeding are the most common sheep breeding practice. Farmers practice both selection and crossbreeding to improve their breeding stocks. Therefore, the economic value each trait should be assessed because it influenced the market value of sheep and the decision of farmers in selecting breeding stocks. The establishment of standard marketing systems and market information calls further investigation.

How Water Can Affect Keratin: Hydration‐Driven Recovery of Bighorn Sheep (Ovis Canadensis) Horns

AbstractKeratin is one of the most common structural biopolymers exhibiting high strength, toughness, and low density. It is found in various tissues such as hairs, feathers, horns, and hooves with various functionalities. For instance, horn keratin absorbs a large amount of energy during intraspecific fights. Keratinized tissues are permanent tissues because of their basic composition consisting of dead keratinized cells that are not able to remodel or regrow once broken or damaged. The lack of a self‐healing mechanism presents a problem for horns, as they are under continued high risk from mechanical damage. In the present work, it is shown for the first time that a combination of material architecture and a water‐assisted recovery mechanism, in the horn of bighorn sheep, endows them with shape and mechanical property recoverability after being subjected to severe compressive loading. Moreover, the effect of hydration is unraveled, on the material molecular structure and mechanical behavior, by means of synchrotron wide angle X‐ray diffraction, Fourier transform infrared spectroscopy, nanoindentation, and in situ and ex situ tensile tests. The recovery and remodeling mechanism is anisotropic and quite distinct to the self‐healing of living tissue such as bones.

ITRAQ-based quantitative proteomic analysis reveals key pathways responsible for scurs in sheep (Ovis aries)

Scurs is a horn phenotype that exhibits as small corneous structures on the skull due to the deformed development of horn tissues. Previous genome-wide association analysis of scurs in Soay sheep showed a significant association to the polled locus, relaxin-like receptor 2 (RXFP2). However, the molecular mechanism underlying the development of scurs remains largely unknown. In the present study, we performed an iTRAQ-based quantitative proteomic analysis of horn tissues from both scurs and normal two-horned and four-horned individuals among Altay sheep to identify the differentially expressed proteins (DEPs) responsible for the scurs phenotype. In total, 232 proteins showed significant differential expression, and the most significant Gene ontology categories were the adhesion processes (biological adhesion (P=4.07×10–17) and cell adhesion (P=3.7×10–16)), multicellular organismal process (single-multicellular organism process (P=2.06x10–11) and multicellular organismal process (P=2.29×10–11)) and extracellular processes (extracellular matrix organization (P=4.77×10–16) and extracellular structure organization (P=4.93×10–16)). Kyoto encyclopedia of genes and genomes (KEGG) analysis showed that extracellular matrix (ECM)-receptor interactions and focal adhesion pathways were the most significant pathways. This finding is consistent with the reduced formation of extracellular matrix in scurs and the development of deformed horn tissues. Our study helps to elucidate the inheritance pattern of sheep horn traits from the perspectives of downstream expressed proteins.

Penerapan Unsur Visual Bentuk Tanduk Domba Garut Dalam Desain Busana Siap Pakai

Fashion design is now being raised on culture, flora, fauna, and local knowledge of the archipelago with a style that is more trendy and dynamic. The uniqueness of Indonesia who brought fashion popular in foreign countries. One of the unique fauna that Indonesia and must be preserved is the Garut sheep. Garut sheep or Ovis aries is an Indonesian fauna originating from Leles, Wanaraja, and Limbangan Garut district. Characteristic of Garut sheep horn has a circular shape (large and thick) are strong, tall body, strong, and large compared to other types of sheep. Garut sheep ram with horns larger, circular, and stronger than the females horn. Sheep fighter also has a unique necklace. Sheep are usually used to fight fights Garut sheep, used the meat for consumption as well as the skin used for the various needs of fashion. The methodology of this research is an exploration, and analysis based on literature sources based on the elements and principles of design by Mayall Theory. In this research, the writer limits design analysis domba Garut in Indonesia on horn sheep arrowroot, which raises moodboard, as a reference for the manufacture of alternative fashion design selected.

Hierarchical structure and compressive deformation mechanisms of bighorn sheep (Ovis canadensis) horn.

Bighorn sheep (Ovis canadensis) horns show remarkable impact resistance and energy absorption when undergoing high speed impact during the intraspecific fights. The present work illustrates the hierarchical structure of bighorn sheep horn at different length scales and investigates the energy dissipation mechanisms under different strain rates, loading orientations and hydration states. These results demonstrate how horn dissipates large amounts of energy, thus provide a new path to fabricate energy absorbent and crashworthiness engineering materials.

Application of three-dimensional printing technology in bone tumor surgery

To discuss the effect of three-dimensional (3D) printing individualized model and guide plate in bone tumor surgery. Between October 2015 and December 2016, 3D printing individualized model and guide plate for making preoperative surgical planning and intraoperative treatment were used in 5 patients of bone tumor. All the patients were male, with a median age of 32 years (range, 9-58 years). There were 1 case of cystic echinococcosis at left pelvis and pathological fracture of the proximal femur; 1 case of left iliac bone osteoblastoma associated with aneurysmal bone cyst; 1 case of fibrous dysplasia of the left femur (sheep horn deformity) with pathological fracture; 1 case of metastatic carcinoma of right calcaneus (tumor staging was T 2N 0M 0); and 1 case of Ewing sarcoma of left femur (tumor staging was T 2N 0M 0). The disease duration ranged from 1 month to 10 years (mean, 2.25 years). The operation was completed successfully. The operation time was 2.6-7.5 hours (mean, 4.9 hours). The intraoperative blood loss was 200-2 500 mL (mean, 1 380 mL). The intraoperative fluoroscopy times was 1-6 times (mean, 3.8 times). There was no infection after operation, and the blood supply and nerve function were good. All the patients were followed up 3-16 months (mean, 5.4 months). No loosening or breaking of the internal fixator occurred. According to Enneking scoring system, the limb function score was 15-26 (mean, 21); and the results were excellent in 2 cases, good in 2 cases, and fair in 1 case. 3D printing technology can make the implementation of the better preoperative planning and evaluation in bone tumor surgery, and it provides a new reference for individualized treatment in patients with bone tumor.

Genome-wide search for signatures of selection in three major Brazilian locally adapted sheep breeds

The study of locally adapted breeds has the potential to underpin the discovery of genes involved in economically and ecologically important traits. Brazilian locally adapted sheep breeds have distinctive characteristics that could be of value for specialized production systems. Therefore, the main objective of the present study was to identify genomic regions that may have been under selection and therefore may explain ecological and production differences observed among three important Brazilian locally adapted sheep breeds. Animals from the Brazilian Creole, Morada Nova and Santa Ines breeds were genotyped using the Illumina Ovine SNP50 BeadChip. The identification of selection signatures was based on two groups of methodologies: differentiation among populations (FST) and linkage disequilibrium (iHS and RsB). Taken together, these analyses allowed for the identification of 86 candidate genes. Functional analysis revealed genes related to immunity, nervous system development, reproduction and sensory perception. A number of genes are of particular interest including: RXFP2, which has recently been associated with the presence/absence and morphology of horns in sheep; the TRPM8 gene, involved in regulation of body temperature at low temperatures; DIS3L2, PLAG1 and NIPBL, associated with height variation; and finally, SPEF2 and SPAG6, important for spermatogenesis. Selective sweeps were identified using multiple methods, and in a number of cases sweep regions contained genes with a demonstrated role in phenotypic variation. The genomic distribution of the sweep regions differed between populations, suggesting that breed specific signatures were successfully identified that may reflect the consequence of local adaptation.

Moisture, anisotropy, stress state, and strain rate effects on bighorn sheep horn keratin mechanical properties.

The horn of the bighorn sheep is an anisotropic composite composed of keratin that is highly sensitive to moisture content. Keratin is also found in many other animals in the form of hooves, claws, beaks, and feathers. Only one previous study contains high rate experimental data, which was performed in the dry condition and only in compression. Considering the bighorn sheep horns' protective role in high speed impacts along with the moisture and strain rate sensitivity, more high strain rate data is needed to fully characterize and model the material. This study provides high strain rate results demonstrating the effects of moisture, anisotropy, and stress state. As a result, the comprehensive data allows modeling efforts to be greatly improved.

Horn and horn core trabecular bone of bighorn sheep rams absorbs impact energy and reduces brain cavity accelerations during high impact ramming of the skull.

Bighorn sheep (Ovis canadensis) routinely experience violent impacts to the head as part of intraspecific fighting. Dynamic 3D finite element models of the skull and horns of a male bighorn sheep were developed to gain an understanding of the roles that the horn and bone materials and structure play in absorbing the impact that occurs during ramming. The geometry and volume mesh of the model were derived from CT scan images. The models included the horn, bony horn core, and bone of the skull. The horn core fills a portion of the hollow horn and consists of a thin cortical bone shell filled with foam-like trabecular bone. Two modified models were also created: one with the distal half of the horn length removed to assess the effects of the tapered spiral geometry of the horn, and one with the internal trabecular bone material of the horn core removed. The trabecular bone material stored three times more strain energy during impact than the horn material in the intact model. Removing half of the horn length had the effect of increasing translational accelerations in the brain cavity by 49%. Removing the trabecular bone in the horn core resulted in a 442% increase in rotational accelerations within the brain cavity. These findings support the investigation of novel bioinspired materials and designs that could be used in mitigating brain injuries and in other applications involving high-impact collisions. Bighorn sheep routinely experience violent impacts to the head and horns without apparent negative consequences to the brain or horns. A portion of the horn is filled with a thin cortical bone shell containing foam-like trabecular bone. We developed novel dynamic finite element models of the skull and horns of bighorn sheep to gain an understanding of the roles that the horn and bone materials play in absorbing the impact that occurs during ramming. The study revealed that both horn and bone materials and the structures made from these materials (i.e., tapered spiral horns and foam-like trabecular bone struts) are important for absorbing impact energy and reducing brain cavity accelerations.

Microstructure and mechanical properties of sheep horn.

The sheep horn presents outstanding mechanical properties of impact resistance and energy absorption, which suits the need of the vehicle bumper design, but the mechanism behind this phenomenon is less investigated. The microstructure and mechanical properties of the sheep horn of Small Tailed Han Sheep (Ovis aries) living in northeast China were investigated in this article. The effect of sampling position and orientation of the sheep horn sheath on mechanical properties were researched by tensile and compression tests. Meanwhile, the surface morphology and microstructure of the sheep horn were observed using scanning electron microscopy (SEM). The formation mechanism of the mechanical properties of the sheep horn was investigated by biological coupling analysis. The analytical results indicated that the outstanding mechanical properties of the sheep horn are determined by configuration, structure, surface morphology and material coupling elements. These biological coupling elements make the sheep horn possess super characteristics of crashworthiness and energy absorption through the internal coupling mechanism. We suppose that these findings would make a difference in vehicle bumper design. Microsc. Res. Tech. 79:664-674, 2016. © 2016 Wiley Periodicals, Inc.

Raman and surface‐enhanced Raman spectroscopy on horns and their correlation with biomechanical properties

Recently horns are considered as potential candidates for various biomedical applications because of their distinct biomechanical properties. We therefore performed Raman spectral analysis and mechanical test on the horns of buffalo, cattle and sheep to obtain information about the molecular compositions in various parts of the horns and their correlation with biomechanical properties. We also developed a surface enhanced Raman spectroscopy (SERS) to trace their degradation products. We found that various parts of the horns have similar overall molecular compositions, but have differences in the bands of C–C–S–S–C–C conformation, α‐helix and β‐sheet conformation, especially in the bands of 507–515 cm−1 which reflect the relative sulfur content and the structural conformation of the disulfide linkages. The Raman intensities at the region are highly correlated with the Young's modulus and tensile strength of the horns, indicating that the biomechanical properties of the horns are mainly determined by their disulfide bonds. It also suggests that Raman spectroscopy has the potential to perform non‐destructive detection on the mechanical strength of horns. The SERS measurements verified that the main constituents of the degradation products from both the buffalo and sheep horns were amino acids and polypeptides, suggesting that the horns are suitable candidates for biomaterial scaffolds. Copyright © 2016 John Wiley & Sons, Ltd.

Discovery of SNPs in RXFP2 related to horn types in sheep

This study was conducted with an attempt to reveal genetic variation in ovine RXFP2, which is a strong candidate gene that is associated with sheep horn development and types. All 18 exons and intro-exon boundary regions as well as 5′ and 3′ gene flanking regions of RXFP2 were re-sequenced using DNA panels representing four typical horn types (normal-horned males, normal-horned females, scurred females, and polled females) in Tan sheep, as well as the DNA pools from Suffolk, a polled sheep breed. A total of 20 previously unreported SNPs were detected. One in the 5′UTR, four in exons, and 15 in the introns. Seven of the 20 SNPs were species-specific variants. A synonymous mutation, p.P375 (c.1125A>G), demonstrating distinct genotypes between horned and hornless individuals, which is located in a conserved region, was regarded as a candidate variant indicating the appearance or absence of horns in sheep.

Design and Analysis of the Bio-Inspired Rear Under-Run Protection Devices for Heavy Truck

The rear under-run protection devices (RUPD) could prevent the entry of a small vehicle under rear side of the heavy truck, and decrease the injuries and deaths when the accident occurs. In this paper, a new concept of the mechanical design of heavy truck RUPD is presented based on the bio-inspired method, by analyzing the structure of a kind of sheep horn, which has good capacities of energy absorption and structural strength. Firstly, the space geometry characteristic of the sheep horn in macroscopic view was analyzed. Then the research was focused on its mechanical property, and the microstructure of the horn sample was observed by the scanning electron microscope (SEM). Based on the test results, the structure characteristic and force condition of the horn were discussed. A new RUPD structure was designed in both macro and micro levels using bionic principle. The superior mechanics performance of the sheep horn was transplanted into the new RUPD. Finally, the finite element model for the new RUPD, which is inspired from the sheep horn, was established and analyzed. Simulation results showed that the protection device had better strength characteristic and could effectively protect car occupants in under-run accidents. Therefore, with the remarkable strength performance and simple structure, the bionic RUPD shows the promise for practical application.

Life: For sheep horns, biggest is not best: Trade‐offs between studliness and survival help less endowed

Life: For sheep horns, biggest is not best: Trade‐offs between studliness and survival help less endowed

Microstructure and mechanical properties of horns derived from three domestic bovines

The microstructure and mechanical properties of horns derived from three domestic bovines (buffalo, cattle and sheep) were examined. The effects of water content, sampling position and orientation of three bovid horns on mechanical properties were systematically investigated by uniaxial tension and micron indentation tests. Meanwhile, the material composition and metal element contents were determined by Raman spectroscopy and elemental analysis respectively, and the microstructures of the horns were measured by scanning electron microscopy (SEM). Results show that the mechanical properties of horns have negative correlation with water contents and depend on sampling position and orientation. The spatial variations of the mechanical properties in horns are attributed to the different keratinization degrees in the proximal, middle and distal parts. And the mechanical properties of horns in the longitudinal direction are better than those in transverse. Among the three kinds of horns, the mechanical properties of buffalo horn are the best, followed by cattle horn, and those in sheep horn are the worst. This is due to the differences in material composition, metal element, and the microstructures of the horns. But the mechanical properties of buffalo horns are not dependent on the source of the buffalo. Therefore, regular engineered buffalo keratinous materials with standard mechanical properties can be obtained from different buffalo horns by using proper preparation methods.

Formation of two-way Lamb waves and force potential wells using single conventional ultrasonic transducer and sheep horn shaped metal piece

A new method is introduced that uses single conventional ultrasonic transducer and a sheep horn shaped metal piece to induce two-way Lamb waves, and furthermore collects leaky Lamb waves to form two force potential wells. The immersion acoustical measurements show that the two-way Lamb waves with adjustable amplitudes can be induced when a 1MHz transducer radiates ultrasonic waves on to the semicircle of a metal “sheep horn”. Furthermore, the results obtained by hydrophone measurement and fluorescence microscope observation verify that the force potential well can be formed in the circle of metal “sheep horn” by the leaky Lamb wave of each way and possibly used to collect the submicro particles. This designed method is intended to provide assistance in limited space for microscope observing by collecting particles within low force potential well. All experiment results also indicate that radiation force and the gradient of force potential well produced by this leaky Lamb wave device is very small due to several reasons including low generation efficiency at semicircle tip and propagation attenuation of Lamb wave in metal piece, near field properties of leaky Lamb wave in liquid, and so on.

Finite Element Analysis of Ramming in Ovis canadensis

The energy produced during the ramming of bighorn sheep (Ovis canadensis) would be expected to result in undesirable stresses in their frontal skull, which in turn would cause brain injury; yet, this animal seems to suffer no ill effects. In general, horn is made of an α-keratin sheath covering a bone. Despite volumes of data on the ramming behavior of Ovis canadensis, the extent to which structural components of horn and horn-associated structure or tissue absorb the impact energy generated by the ramming event is still unknown. This study investigates the hypothesis that there is a mechanical relationship present among the ramming event, the structural constituents of the horn, and the horn-associated structure. The three-dimensional complex structure of the bighorn sheep horn was successfully constructed and modeled using a computed tomography (CT) scan and finite element (FE) method, respectively. Three different three-dimensional quasi-static models, including a horn model with trabecular bone, a horn model with compact bone that instead of trabecular bone, and a horn model with trabecular bone as well as frontal sinuses, were studied. FE simulations were used to compare distributions of principal stress in the horn and the frontal sinuses and the strain energy under quasi-static loading conditions. It was noticed that strain energy due to elastic deformation of the complex structure of horn modeled with trabecular bone and with trabecular bone and frontal sinus was different. In addition, trabecular bone in the horn distributes the stresses over a larger volume, suggesting a mechanical link between the structural constituents and the ramming event. This phenomenon was elucidated through the principal stress distribution in the structure. This study will help designers in choosing appropriate material combinations for the successful design of protective structures against a similar impact.