Proteins from shrews' venom glands play a role in gland functioning and venom production.

Venom production has evolved independently many times in the animal kingdom, although it is rare among mammals. Venomous shrews produce venom in their submandibular salivary glands and use it for food acquisition. Only a few toxins have been identified in shrew venoms thus far, and their modes of action require investigation.

Parasitic Arthropods of Soricinae Shrews in North-Eastern Poland.

The study of the ectoparasite fauna of the insectivores-, , , and (subfamily Soricinae)-was carried out in three locations in Poland: Białowieża National Park, Kosewo Górne in the Masurian Lake District, and in vicinity of Warsaw. Three species of Ixodidae ticks, eleven species of fleas, and four species of mites from the order Mesostigmata were noted. The most numerous ectoparasites are ticks (larvae), (nymphs), and fleas , , and .

Proteins from toad's parotoid macroglands: do they play a role in gland functioning and chemical defence?

Background: Parotoid gland secretion of bufonid toads is a rich source of toxic molecules that are used against predators, parasites and pathogens. Bufadienolides and biogenic amines are the principal compounds responsible for toxicity of parotoid secretion. Many toxicological and pharmacological analyses of parotoid secretions have been performed, but little is known about the processes related to poison production and secretion.

A new, widespread venomous mammal species: hemolytic activity of Sorex araneus venom is similar to that of Neomys fodiens venom.

Background: Venom production has evolved independently many times in the animal kingdom, although it is rare among mammals. Venomous shrews produce toxins in their salivary glands and use their venoms to hunt and store prey. Thus far, the toxicity and composition of shrew venoms have been studied only in two shrew species: the northern short-tailed shrew, Blarina brevicauda, and the Eurasian water shrew, Neomys fodiens.

Dissimilar use of an external heat source for thermoregulation by shrews from different geographic regions.

Ambient temperature has a substantial influence on the thermoregulation costs of small mammals due to their high surface-to-volume ratio. Shrews are among the smallest of mammals and have adopted different behavioral and physiological strategies to deal with cold temperatures. In this study, we assessed the use of an external heat source in the thermoregulatory strategy of two Crocidurinae species, Crocidura russula and C.

Effects of Brain Size on Adult Neurogenesis in Shrews.

Shrews are small animals found in many different habitats. Like other mammals, adult neurogenesis occurs in the subventricular zone of the lateral ventricle (SVZ) and the dentate gyrus (DG) of the hippocampal formation. We asked whether the number of new generated cells in shrews depends on their brain size.

Venom Use in Eulipotyphlans: An Evolutionary and Ecological Approach.

Venomousness is a complex functional trait that has evolved independently many times in the animal kingdom, although it is rare among mammals. Intriguingly, most venomous mammal species belong to Eulipotyphla (solenodons, shrews). This fact may be linked to their high metabolic rate and a nearly continuous demand of nutritious food, and thus it relates the venom functions to facilitation of their efficient foraging.

Individual variation in cardiotoxicity of parotoid secretion of the common toad, Bufo bufo, depends on body size - first results.

Anurans secrete a wide diversity of toxins from skin glands to defend themselves against predators and pathogens. Bufonids produce potent poison in parotoid macroglands located in the postorbital region. Parotoid secretion is a rich source of bioactive compounds with cardiotoxic, cytotoxic and hemolytic activity.

The Competition Between Immatures of Ixodes ricinus and Dermacentor reticulatus (Ixodida: Ixodidae) Ticks for Rodent Hosts.

The numbers of Ixodes ricinus (L.) and Dermacentor reticulatus (Fabricius) larvae and nymphs attached to small mammals are influenced by interspecific competition. The present study analyses data collected over several years in two study areas: Kosewo Górne (Mazurian District, N Poland; between July 1997 and July 2009) and Białowieża Primeval Forest (E Poland; in July 2007).

A suspensory way of life: Integrating locomotion, postures, limb movements, and forces in two-toed sloths Choloepus didactylus (Megalonychidae, Folivora, Pilosa).

Over the last decade, we have learned much about the anatomy, evolutionary history, and biomechanics of the extant sloths. However, most of this study has involved studying sloths in controlled conditions, and few studies have explored how these animals are behaving in a naturalistic setting. In this study, we integrate positional activities in naturalistic conditions with kinematic and kinetic observations collected on a simulated runway to best capture the biomechanical behavior of Linnaeus's two-toed sloths.

Locomotion, postures, substrate use, and foot grasping in the marsupial feathertail glider Acrobates pygmaeus (Diprotodontia: Acrobatidae): Insights into early euprimate evolution.

Debates on early euprimate evolution are related to the understanding of the ecological context that promoted their unique adaptations. Currently, these discussions mainly revolve around the habitual use of the small-branch niche or the frequent utilization of wider, and probably, strongly inclined substrates by euprimate ancestors. The current fossil evidence implies a diversity of arboreal quadrupedal behaviors for these early euprimates, associated with the use of various types of substrates.

Toxic activity and protein identification from the parotoid gland secretion of the common toad Bufo bufo.

Anuran toxins released from the skin glands are involved in defence against predators and microorganisms. Secretion from parotoid macroglands of bufonid toads is a rich source of bioactive compounds with the cytotoxic, cardiotoxic and hemolytic activity. Bufadienolides are considered the most toxic components of the toad poison, whereas the protein properties are largely unknown.

Evaluation of the physiological activity of venom from the Eurasian water shrew .

Background: Animal toxins can have medical and therapeutic applications. Principally, toxins produced by insects, arachnids, snakes and frogs have been characterized. Venomous mammals are rare, and their venoms have not been comprehensively investigated.

Arboreal Locomotion in Eurasian Harvest Mice Micromys Minutus (Rodentia: Muridae): The Gaits of Small Mammals.

Body size imposes significant constraints on arboreal locomotion. Despite the wealth of research in larger arboreal mammals, there is a lack of data on arboreal gaits of small mammals. In this context, the present study explores arboreal locomotion in one of the smallest rodents, the Eurasian harvest mice Micromys minutus (∼10 g).

Negative effects of density on space use of small mammals differ with the phase of the masting-induced population cycle.

Home range size generally decreases with increasing population density, but testing how this relationship is influenced by other factors (e.g., food availability, kin structure) is a difficult task.

The transstadial persistence of tick-borne encephalitis virus in Dermacentor reticulatus ticks in natural conditions.

There are a number of reports regarding natural infection of Dermacentor reticulatus ticks with TBE virus; however, the transmission mode of TBE virus in this tick population has not been investigated. This study was conducted in Białowieża Primeval Forest, east Poland. Forty fully engorged nymphs of D.

Diagonal gaits in the feathertail glider Acrobates pygmaeus (Acrobatidae, Diprotodontia): Insights for the evolution of primate quadrupedalism.

Research on primate origins has revolved around arboreality and, more specifically, the adaptations that are linked to safe navigation in the fine-branch niche. To this end, extant non-primate mammals have been used as models to assess the significance of these adaptations. However, the size of these models is larger than that estimated for early primates.

Sex differences in flea infections among rodent hosts: is there a male bias?

Recognizing patterns of parasite distribution among wildlife hosts is of major importance due to growing risk of transmission of zoonotic diseases to humans. Thus, sex-dependent parasite distribution in higher vertebrates is extensively studied, and males are often found more parasitized than females. Male-biased parasitism may be the result of weaker immunocompetence of male hosts owing to the immunosuppressive effect of androgens.

Differentiation of flea communities infesting small mammals across selected habitats of the Baltic coast, central lowlands, and southern mountains of Poland.

Only a few studies comparing flea composition on the coast and in the mountains have been conducted. We investigated differences in flea communities infesting small mammals in selected habitats in northern, central, and southern Poland. We predicted (1) a greater number of flea species in the southeastern Poland and a lower number in the north, (2) a greater number of flea species in fertile and wet habitats than in poor and arid habitats, and (3) a low similarity of flea species between flea communities in western and eastern Poland.

Winter reduction in body mass in a very small, nonhibernating mammal: consequences for heat loss and metabolic rates.

Low temperatures in northern winters are energetically challenging for mammals, and a special energetic burden is expected for diminutive species like shrews, which are among the smallest of mammals. Surprisingly, shrews shrink their body size in winter and reduce body and brain mass, an effect known as Dehnel's phenomenon, which is suggested to lower absolute energy intake requirements and thereby enhance survival when food availability is low. Yet reduced body size coupled with higher body-surface-to-mass ratio in these tiny mammals may result in thermoregulatory heat production at a given temperature constituting a larger proportion of the total energy expenditure.

Apparent scarcity of glial fibrillary acidic protein expression in the brain of the pygmy shrew Sorex minutus as revealed by immunocytochemistry.

We examined astroglial cells in the brain of the pygmy shrew Sorex minutus (Insectivora). For that purpose we labeled glial fibrillary acidic protein (GFAP) immunohistochemically in brain sections with a polyclonal antibody. Antigen retrieval experiments were performed to counteract formaldehyde fixation masking of GFAP epitopes.