-
Platelets May 2020Hemostasis is the normal process that produces a blood clot at a site of vascular injury. Mice are widely used to study hemostasis and abnormalities of blood coagulation... (Review)
Review
Hemostasis is the normal process that produces a blood clot at a site of vascular injury. Mice are widely used to study hemostasis and abnormalities of blood coagulation because their hemostatic system is similar in most respects to that of humans, and their genomes can be easily manipulated to create models of inherited human coagulation disorders. Two of the most widely used techniques for assessing hemostasis in mice are the tail bleeding time (TBT) and saphenous vein bleeding (SVB) models. Here we discuss the use of these methods in the evaluation of hemostasis, and the advantages and limits of using mice as surrogates for studying hemostasis in humans.
Topics: Animals; Bleeding Time; Blood Coagulation; Disease Models, Animal; Hemorrhage; Hemostasis; Humans; Lacerations; Liver; Mice; Saphenous Vein; Tail
PubMed: 31992118
DOI: 10.1080/09537104.2020.1719056 -
Journal of Visualized Experiments : JoVE Feb 2021Lymphedema is extremity swelling caused by lymphatic dysfunction. The affected limb enlarges because of accumulation of fluid, adipose, and fibrosis. There is no cure...
Lymphedema is extremity swelling caused by lymphatic dysfunction. The affected limb enlarges because of accumulation of fluid, adipose, and fibrosis. There is no cure for this disease. A mouse tail model that uses a focal full thickness skin excision near the base of the tail, resulting in tail swelling, has been used to study lymphedema. However, this model may result in vascular comprise and consequent tail necrosis and early tail swelling resolution, limiting its clinical translatability. The chronic murine tail lymphedema model induces sustained lymphedema over 15 weeks and a reliable perfusion to the tail. Enhancements of the traditional murine tail lymphedema model include 1) precise full thickness excision and lymphatic clipping using a surgical microscope, 2) confirmation of post-operative arterial and venous perfusion using high resolution laser speckle, and 3) functional assessment using indocyanine green near infrared laser lymphangiography. We also use tissue nanotransfection technology (TNT) for novel non-viral, transcutaneous, focal delivery of genetic cargo to the mouse tail vasculature.
Topics: Animals; Disease Models, Animal; Female; Imaging, Three-Dimensional; Lymphatic Vessels; Lymphedema; Mice, Inbred C57BL; Nanotechnology; Tail; Mice
PubMed: 33645579
DOI: 10.3791/61848 -
Anatomical Record (Hoboken, N.J. : 2007) Oct 2012Many lizards are able to undergo scar-free wound healing and regeneration following loss of the tail. In most instances, lizard tail loss is facilitated by autotomy, an...
Many lizards are able to undergo scar-free wound healing and regeneration following loss of the tail. In most instances, lizard tail loss is facilitated by autotomy, an evolved mechanism that permits the tail to be self-detached at pre-existing fracture planes. However, it has also been reported that the tail can regenerate following surgical amputation outside the fracture plane. In this study, we used the leopard gecko, Eublepharis macularius, to investigate and compare wound healing and regeneration following autotomy at a fracture plane and amputation outside the fracture plane. Both forms of tail loss undergo a nearly identical sequence of events leading to scar-free wound healing and regeneration. Early wound healing is characterized by transient myofibroblasts and the formation of a highly proliferative wound epithelium immunoreactive for the wound keratin marker WE6. The new tail forms from what is commonly referred to as a blastema, a mass of proliferating mesenchymal-like cells. Blastema cells express the protease matrix metalloproteinase-9. Apoptosis (demonstrated by activated caspase 3 immunostaining) is largely restricted to isolated cells of the original and regenerating tail tissues, although cell death also occurs within dermal structures at the original-regenerated tissue interface and among clusters of newly formed myocytes. Furthermore, the autotomized tail is unique in demonstrating apoptosis among cells adjacent to the fracture planes. Unlike mammals, transforming growth factor-β3 is not involved in wound healing. We demonstrate that scar-free wound healing and regeneration are intrinsic properties of the tail, unrelated to the location or mode of tail detachment.
Topics: Amputation, Surgical; Animals; Cicatrix; Lizards; Random Allocation; Regeneration; Tail; Wound Healing
PubMed: 22933425
DOI: 10.1002/ar.22490 -
Integrative and Comparative Biology Sep 2021Synopsis Tails are a defining characteristic of chordates and show enormous diversity in function and shape. Although chordate tails share a common evolutionary and... (Review)
Review
Synopsis Tails are a defining characteristic of chordates and show enormous diversity in function and shape. Although chordate tails share a common evolutionary and genetic-developmental origin, tails are extremely versatile in morphology and function. For example, tails can be short or long, thin or thick, and feathered or spiked, and they can be used for propulsion, communication, or balancing, and they mediate in predator-prey outcomes. Depending on the species of animal the tail is attached to, it can have extraordinarily multi-functional purposes. Despite its morphological diversity and broad functional roles, tails have not received similar scientific attention as, for example, the paired appendages such as legs or fins. This forward-looking review article is a first step toward interdisciplinary scientific synthesis in tail research. We discuss the importance of tail research in relation to five topics: (1) evolution and development, (2) regeneration, (3) functional morphology, (4) sensorimotor control, and (5) computational and physical models. Within each of these areas, we highlight areas of research and combinations of long-standing and new experimental approaches to move the field of tail research forward. To best advance a holistic understanding of tail evolution and function, it is imperative to embrace an interdisciplinary approach, re-integrating traditionally siloed fields around discussions on tail-related research.
Topics: Animals; Tail
PubMed: 33999184
DOI: 10.1093/icb/icab082 -
The International Journal of... 2020Anuran tadpoles are excellent models for regeneration studies. The tail, an organ essential for swimming for the aquatic tadpole, regenerates completely following injury... (Review)
Review
Anuran tadpoles are excellent models for regeneration studies. The tail, an organ essential for swimming for the aquatic tadpole, regenerates completely following injury or amputation. However, treatment with the morphogen, vitamin A or retinoic acid inhibits normal tail regeneration and induces homeotic transformation of tail to limbs. This phenomenon was discovered for the first time in the Indian marbled balloon frog Uperodon systoma in the Developmental Biology laboratory of Utkal University (Odisha, India) in the year 1992. In this paper, we present the results of morphological, histological, biochemical and molecular (immonohistochemistry) investigations of vitamin A induced homeotic transformation in different anuran species. In addition, we discuss the putative role of fibroblast growth factor 1 during spinal cord regeneration in the tadpoles of the Indian tree frog, Polypedates maculatus, an ideal model for regeneration studies in an Indian context.
Topics: Animals; Anura; Extremities; Larva; Morphogenesis; Regeneration; Tail; Vitamin A
PubMed: 32659020
DOI: 10.1387/ijdb.190230pm -
Genes Jul 2021The question of why animals vary in their ability to regenerate remains one of the most intriguing questions in biology. Annelids are a large and diverse phylum, many... (Comparative Study)
Comparative Study Review
The question of why animals vary in their ability to regenerate remains one of the most intriguing questions in biology. Annelids are a large and diverse phylum, many members of which are capable of extensive regeneration such as regrowth of a complete head or tail and whole-body regeneration, even from few segments. On the other hand, some representatives of both of the two major annelid clades show very limited tissue regeneration and are completely incapable of segmental regeneration. Here we review experimental and descriptive data on annelid regeneration, obtained at different levels of organization, from data on organs and tissues to intracellular and transcriptomic data. Understanding the variety of the cellular and molecular basis of regeneration in annelids can help one to address important questions about the role of stem/dedifferentiated cells and "molecular morphallaxis" in annelid regeneration as well as the evolution of regeneration in general.
Topics: Animals; Annelida; Head; Regeneration; Tail
PubMed: 34440322
DOI: 10.3390/genes12081148 -
Integrative and Comparative Biology Sep 2021Determining how variation in morphology affects animal performance (and ultimately fitness) is key to understanding the complete process of evolutionary adaptation. Long...
Determining how variation in morphology affects animal performance (and ultimately fitness) is key to understanding the complete process of evolutionary adaptation. Long tails have evolved many times in arboreal and semi-arboreal rodents; in deer mice, long tails have evolved repeatedly in populations occupying forested habitat even within a single species (Peromyscus maniculatus). Here, we use a combination of functional modeling, laboratory studies, and museum records to test hypotheses about the function of tail-length variation in deer mice. First, we use computational models, informed by museum records documenting natural variation in tail length, to test whether differences in tail morphology between forest and prairie subspecies can influence performance in behavioral contexts relevant for tail use. We find that the deer- mouse tail plays little role in statically adjusting center of mass or in correcting body pitch and yaw, but rather it can affect body roll during arboreal locomotion. In this context, we find that even intraspecific tail-length variation could result in substantial differences in how much body rotation results from equivalent tail motions (i.e., tail effectiveness), but the relationship between commonly-used metrics of tail-length variation and effectiveness is non-linear. We further test whether caudal vertebra length, number, and shape are associated with differences in how much the tail can bend to curve around narrow substrates (i.e., tail curvature) and find that, as predicted, the shape of the caudal vertebrae is associated with intervertebral bending angle across taxa. However, although forest and prairie mice typically differ in both the length and number of caudal vertebrae, we do not find evidence that this pattern is the result of a functional trade-off related to tail curvature. Together, these results highlight how even simple models can both generate and exclude hypotheses about the functional consequences of trait variation for organismal-level performance.
Topics: Animals; Biological Evolution; Ecosystem; Locomotion; Peromyscus; Tail
PubMed: 33871633
DOI: 10.1093/icb/icab030 -
Schweizer Archiv Fur Tierheilkunde Apr 2022Tail biting and lesions are common problems in modern pig production. In 2008 tail docking to prevent tail biting was banned in Switzerland. Since then pigs have been...
Tail biting and lesions are common problems in modern pig production. In 2008 tail docking to prevent tail biting was banned in Switzerland. Since then pigs have been raised with intact tails. This study aimed to assess the current prevalence of tail lesions at Swiss abattoirs and comparing abattoir data with farm-specific data regarding potential risk factors for tail lesions. Data collection was performed in repetitive cycles of two weeks at four abattoirs during all consecutive seasons of one year. Gender, tail length and the tail tip condition were evaluated among other parameters. During 32 weeks in total, 195 704 pigs from 6112 batches from 2510 herds were evaluated. Overall, 63,2 % of the animals included in the analysis were slaughtered with a complete tail (lowest tail length score [TLS]), whereas 36,8 % showed a partial or total loss of the tail. The condition of the tail tip (tail tip condition score [TTCS]) was judged as being intact in 63,0 %, as a healed lesion in 23,7 %, an acute lesion in 1,3 % and a chronic lesion in 12,0 % of all cases. Male animals had significantly higher values for TLS and TTCS than female animals (P ≤ 0,05). TLS values were significantly higher in winter than in spring and summer (P < 0,001). TTCS values were significantly higher in fall than in spring and summer. TLS and TTCS values differed significantly (P < 0,001) between the four abattoirs. Only few significant correlations were found between values of TLS and TTCS and farm-specific data. Recording tail lesions at abattoirs is an accurate method to investigate the prevalence of tail lesions in fattening pigs. However, to monitor animal welfare on herd level, this method is very labor intensive. Moreover, data on tail lesions collected at the abattoir cannot replace veterinary on-farm examination for risk factor identification.
Topics: Abattoirs; Animal Welfare; Animals; Bites and Stings; Female; Male; Prevalence; Swine; Switzerland; Tail
PubMed: 35383031
DOI: 10.17236/sat00352 -
Stem Cells and Development Oct 2018Urodele amphibians have a tremendous capacity for the regeneration of appendages, including limb and tail, following injury. While studies have focused on the cellular...
Urodele amphibians have a tremendous capacity for the regeneration of appendages, including limb and tail, following injury. While studies have focused on the cellular and morphological changes during appendicular regeneration, the signaling mechanisms that govern these cytoarchitectural changes during the regenerative response are unclear. In this study, we describe the essential role of hedgehog (Hh) and Wnt signaling pathways following tail amputation in the newt. Quantitative PCR studies revealed that members of both the Hh and Wnt signaling pathways, including the following: shh, ihh, ptc-1, wnt-3a, β-catenin, axin2, frizzled (frzd)-1, and frzd-2 transcripts, were induced following injury. Continuous pharmacological-mediated inhibition of Hh signaling resulted in spike-like regenerates with no evidence of tissue patterning, whereas activation of Hh signaling enhanced the regenerative process. Pharmacological-mediated temporal inhibition experiments demonstrated that the Hh-mediated patterning of the regenerating tail occurs early during regeneration and Hh signals are continuously required for proliferation of the blastemal progenitors. BrdU incorporation and PCNA immunohistochemical studies demonstrated that Hh signaling regulates the cellular proliferation of the blastemal cells following amputation. Similarly, Wnt inhibition resulted in perturbed regeneration, whereas its activation promoted tail regeneration. Using an inhibitor-activator strategy, we demonstrated that the Wnt pathway is likely to be upstream of the Hh pathway and together these signaling pathways function in a coordinated manner to facilitate tail regeneration. Mechanistically, the Wnt signaling pathway activated the Hh signaling pathway that included ihh and ptc-1 during the tail regenerative process. Collectively, our results demonstrate the absolute requirement of signaling pathways that are essential in the regulation of tail regeneration.
Topics: Animals; Cell Proliferation; Extremities; Gene Expression Regulation, Developmental; Hedgehog Proteins; Regeneration; Salamandridae; Tail; Wnt Proteins; Wnt Signaling Pathway
PubMed: 30003832
DOI: 10.1089/scd.2018.0049 -
Journal of Animal Science Nov 2017A study was conducted to evaluate the effect of tail docking on the welfare and performance of victimized pigs by tail biting and tail biters. Pigs ( = 240; 25.7 ± 2.9...
A study was conducted to evaluate the effect of tail docking on the welfare and performance of victimized pigs by tail biting and tail biters. Pigs ( = 240; 25.7 ± 2.9 kg average weight), including 120 pigs that were tail docked at birth and 120 pigs that remained with intact tails, were used. Pigs were housed in 8 pens of 30 pigs in a confinement barn for 16 wk, with 4 pens each housing pigs of both sexes with docked or intact tails. Tail biters and victimized pigs with damaged tails were identified during outbreaks of tail biting. Growth performance was monitored, and skin lesions on the tail, ears, and body were assessed. Blood samples were collected from focal tail biters, victimized pigs, and nonvictimized pigs for analysis of total serum protein, IgG, and substance P concentrations. When pigs were marketed, carcass weights and the number of pigs with carcass trim loss were recorded. During the growing-finishing period, 48% of pigs with docked tails and 89% of pigs with intact tails experienced lesions on their tails, including 5% of docked pigs and 30% of intact pigs identified as victimized pigs that experienced puncture wounds with signs of infection on their tails or loss of tails ( < 0.001). Victimized pigs tended to gain less weight ( = 0.07) between 17 and 21 wk of age than other pigs when tail biting prevailed in this study. Victimized pigs were more frequently ( = 0.04) sold for less than full value and had a lower dressing percentage ( < 0.001) compared with nonvictimized pigs. For victimized pigs, total serum protein and IgG concentrations were elevated 5 d after tails were injured, suggesting that tail damage can cause inflammation, which may lead to carcass abscesses and trim loss. Compared with victimized pigs and nonvictimized pigs, tail biters had lower total serum protein ( = 0.01) and IgG ( = 0.01) concentrations, indicating that tail biters may experience poor immune functions. Results of this study demonstrated that tail docking reduced tail damage in pigs kept in a confinement system. Tail damage can cause inflammation and reduce the value of market pigs. More research is needed to test whether compromised immune functions predispose pigs to tail biting.
Topics: Animal Welfare; Animals; Behavior, Animal; Bites and Stings; Female; Housing, Animal; Male; Swine; Tail
PubMed: 29293713
DOI: 10.2527/jas2017.1571