Morphology of sweat glands in the skin of Saimaa (Pusa hispida saimensis) and Baltic ringed (Pusa hispida botnica) seals.

The endangered Saimaa ringed seal (Pusa hispida saimensis) is an endemic freshwater subspecies inhabiting Lake Saimaa in Finland. The Baltic ringed seal (Pusa hispida botnica) inhabits the brackish Baltic Sea, which is almost entirely landlocked. Recent research shows that Saimaa and Baltic ringed seals may be genetically even further apart from each other than from other ringed seal subspecies. We documented histologically the integument microstructure of Saimaa and Baltic ringed seals to determine whether the geographic and genetic isolation was manifested as variation in the integument microstructure of these subspecies adapted to icy aquatic environments. The skin structures of these subspecies were similar to those of other phocids. The association of the sweat glands with hair follicles in both subspecies suggested that they were small apocrine sweat glands described previously in terrestrial or aquatic mammals. None of the apocrine glands had large lumina, and some of the ducts were relatively straight and short. Further studies analysing the mode of secretion, for example, apocrine versus eccrine, in the sweat glands are necessary to confirm the types of sweat glands in seals.

Comparison of chemical and enzymatic maceration processes for soft tissue removal from arterial silicone casts on skull scaffolds.

The various models used in gross anatomical studies to improve the visualization of blood vessels differ in the amount of manual labour, cost, equipment and time involved. This study aimed to compare chemical and enzymatic maceration processes for soft-tissue removal from arterial silicone casts on skull scaffolds using ringed seal (Pusa hispida) skull specimens. Both processes produced specimens that covered all anatomical aspects required to visualize the intracranial arterial arrangement on a bone scaffold. Overall, the enzyme maceration process was better for production of such specimens, as this process is easy and safe to perform, is less harmful to the bony parts of the specimen, and the resulting specimens are visually more appealing for display and teaching. Compared with previously published models, the end result varied in the amount of dissolved bone tissue and the visual presentation of the model.

Anatomical variations in the cerebral arterial circle of the Saimaa (Pusa hispida saimensis) and Baltic ringed seals (Pusa hispida botnica).

The intracranial arterial vascularization of the Saimaa ringed seals (Pusa hispida saimensis; Nordquist, 1899) and Baltic ringed seals (Pusa hispida botnica; Gmelin, 1788) disclosed patterns of anatomical architecture comparable to that of other pinniped species. Arterial silicone casts on skull scaffolds, and magnetic resonance imaging (MRI) showed that the besides joining the caudal communicating arteries upon entering the cerebral arterial circle, the bilateral internal carotid arteries bifurcated as laterally oriented rostral choroidal arteries and rostral cerebral arteries. The latter arteries almost immediately gave off the laterally oriented middle cerebral arteries. Numerous individual variations were evident in differences in the exact branching sites of bilateral vessels or the size or number of arterial branches. Two Saimaa ringed seals had only a tiny foramen for the left internal carotid artery to enter the intracranial space, and the intracranial part of this vessel was short. It did not reach the cerebral arterial circle. The intracranial part of the right internal carotid artery is bifurcated and also supplied the left side of the cerebral arterial circle. Both specimens had aplasia of the left rostral cerebral artery. The intracranial arterial arrangement of Saimaa and Baltic ringed seals reflects the arterial architecture of this body region in terrestrial mammals with little evidence for aquatic adaptations or changes related to thermoregulation.

The impact of wildlife and environmental factors on hantavirus infection in the host and its translation into human risk.

Identifying factors that drive infection dynamics in reservoir host populations is essential in understanding human risk from wildlife-originated zoonoses. We studied zoonotic Puumala orthohantavirus (PUUV) in the host, the bank vole (Myodes glareolus), populations in relation to the host population, rodent and predator community and environment-related factors and whether these processes are translated into human infection incidence. We used 5-year rodent trapping and bank vole PUUV serology data collected from 30 sites located in 24 municipalities in Finland. We found that PUUV seroprevalence in the host was negatively associated with the abundance of red foxes, but this process did not translate into human disease incidence, which showed no association with PUUV seroprevalence. The abundance of weasels, the proportion of juvenile bank voles in the host populations and rodent species diversity were negatively associated with the abundance index of PUUV positive bank voles, which, in turn, showed a positive association with human disease incidence. Our results suggest certain predators, a high proportion of young bank vole individuals, and a diverse rodent community, may reduce PUUV risk for humans through their negative impacts on the abundance of infected bank voles.

Hip and stifle joint anatomy of the Saimaa (Pusa hispida saimensis) and Baltic ringed seals (Pusa hispida botnica).

The anatomical architecture of the hip and stifle joints of the Saimaa ringed seal was determined by dissection to be similar to that of the Baltic ringed seal. There was no ligament of the femoral head in the hip joint. The lateral side of the stifle joint lacked a collateral ligament but the collateral ligament on the medial side was of considerable size. The medial meniscus was larger and thicker than the lateral meniscus. The asymmetrical anatomical architecture allows for much lateral movement during aquatic motion, but it is poorly adapted to terrestrial locomotion.

Distribution and morphology of ventricular bands in the hearts of ringed seals.

In contrast to studies on domestic animals, few reports describe ventricular bands in wildlife, and none in aquatic mammals. Ventricular bands in the endangered Saimaa ringed seal (Pusa hispida saimensis) and the Baltic ringed seal (Pusa hispida botnica) were examined as part of an ongoing research on the comparative anatomy of ringed seal subspecies. The dissections illustrated that a varying number of thin or thick ventricular bands from the papillary muscles to the ventricular walls were visible in the ventricles of all ringed seal specimens examined. The histological appearance of the ventricular bands was characterized by a fibromuscular pattern.

Unique hip and stifle extensor muscle patterns in the Eurasian lynx, Lynx lynx (Carnivora: Felidae).

The Eurasian lynx (Lynx lynx) is a medium-sized felid, with a tendency to hunt for prey larger than itself. We studied the lynx hindlimb musculoskeletal anatomy in order to determine possible anatomical adaptations to hunting large prey. In our previous work, we had found characters of both large and small felids in the lynx forelimb. The crouched limbs, typical of all felids, increase the energy demands for the antigravity muscles during locomotion. As a powerful pounce is required for the smaller felid to bring down large prey, strong hindquarters may be needed. We hypothesized that the muscle attachments are more mechanically advantageous and muscles heavier in the lynx as compared to other felids to compensate for the energy requirements. In support of this, we found unique patterns in the hindlimb musculature of the lynx. Insertion of the m. gluteus medius was large with a short moment arm around the hip joint, providing mechanical disadvantage, but rapid movement. The musculus vastus medialis was relatively heavier than in other felids emphasizing the role of the m. quadriceps femoris as a powerful stifle extensor. The extensor muscles support the crouched hind limbs, which is crucial when tackling large prey, and they are also responsible for the swift powerful pounce brought by extending the hindlimbs. However, we cannot rule out the possibility the characters are shared with other Lynx spp. or they are adaptations to other aspects of the locomotor strategy in the Eurasian lynx.

Drawing in Veterinary Anatomy Education: What Do Students Use It For?

In contrast to medical education, information on the use of arts as a learning approach is scarce in veterinary anatomy. The aim of this prospective, questionnaire-based study was to survey students' use of drawing in various aspects of veterinary anatomy learning (self-study, examinations, preparation for, and reflection on cadaver dissection). The quantitative data showed that first-year students with artistic preferences used drawing significantly more often in most aspects of anatomy learning than students with no such preferences, apart from the reported use of drawing in examinations and for reflection after cadaver dissection. The lack of significant correlations of the reported use of drawing in examinations with any other study variable provided support for the author's observation that student-generated drawings are not as commonly used in examinations as previously. In contrast to the study hypothesis, previous university studies did not correlate significantly with any aspect of the use of drawing in anatomy learning. None of the reported uses of drawing addressed the benefits of drawing in learning the comparative anatomy of animal species, a characteristic distinguishing veterinary anatomy from human anatomy. Qualitative student feedback indicated that encouragement and teacher-produced images would increase the use of drawing as a learning approach even if the implementation of drawing into the curriculum is not feasible. Conclusions from this study were implemented through self-directed learning in anatomy courses that replaced the canceled cadaveric dissections during the COVID-19 outbreak and also through the ongoing drawing workshops to further advance the use of drawing in veterinary anatomy learning.

Estimating the amount of collagen and elastic fibres in bovine teats.

The amount of collagen and elastic fibres near the Fürstenberg's rosette in histological sections of bovine teats was estimated using the ImageJ image processing software. This method holds promise for comparing tissue types within and between sections but it was not a reliable way to quantify the absolute amount of tissue types in a sample. The amount of elastic fibres and collagen was similar in cow teats with a history or acute case of mastitis infection and in non-infected cows, but this could not be statistically tested due to limitations in the study material.

Fostering Students' Collaborative Learning Competencies and Professional Conduct in the Context of Two Gross Anatomy Courses in Veterinary Medicine.

Collaborative learning has been used in anatomy courses to support students' learning of challenging topics but the success of group work depends significantly on the students' ability to communicate in a professional manner. Veterinary students' experiences with tasks related to collaborative learning and professional conduct were studied by comparing learning collaborative competences and pedagogy, as well as perceived positive and challenging aspects, in two gross anatomy courses. Both qualitative and quantitative data were collected from students' experiences of course assignments and collaboration, as well as from self-evaluated collaboration competence development. Trying things out oneself, practical application and professional conduct were positively highlighted particularly in the first-year course (myology and arthrology) group work and learning from others more in the second year (topographical anatomy). Various group work challenges, often relating to practical matters or communication, were the key concerns for students. The main difference between the two courses in learning of collaborative knowledge work competencies appeared to relate to the nature of the group work assignment. The topography course included the element of collaboration in preparing a presentation and teaching session for the rest of the class. Interestingly, students on the myology and arthrology course gave more positive comments on professional conduct than the students on the topography course despite the fact that the latter course included more practical elements relating to their future profession.

Population- and Individual-Level Dynamics of the Intestinal Microbiota of a Small Primate.

UNLABELLED: Longitudinal sampling for intestinal microbiota in wild animals is difficult, leading to a lack of information on bacterial dynamics occurring in nature. We studied how the composition of microbiota communities changed temporally in free-ranging small primates, rufous mouse lemurs (Microcebus rufus). We marked and recaptured mouse lemurs during their mating season in Ranomafana National Park in southeastern mountainous rainforests of Madagascar for 2 years and determined the fecal microbiota compositions of these mouse lemurs with MiSeq sequencing. We collected 160 fecal samples from 71 animals and had two or more samples from 39 individuals. We found small, but statistically significant, effects of site and age on microbiota richness and diversity and effects of sex, year, and site on microbiota composition, while the within-year temporal trends were less clear. Within-host microbiota showed pervasive variation in intestinal bacterial community composition, especially during the second study year. We hypothesize that the biological properties of mouse lemurs, including their small body size and fast metabolism, may contribute to the temporal intraindividual-level variation, something that should be testable with more-extensive sampling regimes. IMPORTANCE: While microbiome research has blossomed in recent years, there is a lack of longitudinal studies on microbiome dynamics on free-ranging hosts. To fill this gap, we followed mouse lemurs, which are small heterothermic primates, for 2 years. Most studied animals have shown microbiota to be stable over the life span of host individuals, but some previous research also found ample within-host variation in microbiota composition. Our study used a larger sample size than previous studies and a study setting well suited to track within-host variation in free-ranging mammals. Despite the overall microbiota stability at the population level, the microbiota of individual mouse lemurs can show large-scale changes in composition in time periods as short as 2 days, suggesting caution in inferring individual-level patterns from population-level data.

Musculoskeletal anatomy of the Eurasian lynx, Lynx lynx (Carnivora: Felidae) forelimb: Adaptations to capture large prey?

Mammalian carnivores adhere to two different feeding strategies relative to their body masses. Large carnivores prey on animals that are the same size or larger than themselves, whereas small carnivores prey on smaller vertebrates and invertebrates. The Eurasian lynx (Lynx lynx) falls in between these two categories. Lynx descend from larger forms that were probably large prey specialists, but during the Pleistocene became predators of small prey. The modern Eurasian lynx may be an evolutionary reversal toward specializing in large prey again. We hypothesized that the musculoskeletal anatomy of lynx should show traits for catching large prey. To test our hypothesis, we dissected the forelimb muscles of six Eurasian lynx individuals and compared our findings to results published for other felids. We measured the bones and compared their dimensions to the published material. Our material displayed a well-developed pectoral girdle musculature with some uniquely extensive muscle attachments. The upper arm musculature resembled that of the pantherine felids and probably the extinct sabertooths, and also the muscles responsible for supination and pronation were similar to those in large cats. The muscles controlling the pollex were well-developed. However, skeletal indices were similar to those of small prey predators. Our findings show that lynx possess the topographic pattern of muscle origin and insertion like in large felids. J. Morphol. 277:753-765, 2016. © 2016 Wiley Periodicals, Inc.

Macroscopic Anatomy of the Saimaa Ringed Seal (Phoca hispida saimensis) Lower Respiratory Tract.

We studied the macroscopic anatomy of the lower respiratory tract of the endangered Saimaa ringed seal (Phoca hispida saimensis). Examination of one adult and one young individual found dead showed that trachea had 85 and 86 complete cartilage rings. The adjacent cartilages exhibited very few random anastomoses. There was variation in the confirmation of the trachea between the cranial and caudal part of the trachea. The right lung was divided by partly incomplete inter-lobar fissures into cranial, middle, caudal, and accessory lobes. The left lung consisted of cranial, middle, and caudal lobes. The lungs were characterized by a high amount of interlobular connective tissue. Silicone casts were prepared of the two specimens to visualize the tracheobronchial branching which was similar to that of marine ringed seals but in the Saimaa ringed seal the right middle lobar bronchus originated at the same level as the accessory lobar bronchus.

Tracking year-to-year changes in intestinal nematode communities of rufous mouse lemurs (Microcebus rufus).

While it is known that intestinal parasite communities vary in their composition over time, there is a lack of studies addressing how variation in component communities (between-hosts) manifests in infracommunities (within-host) during the host lifespan. In this study, we investigate the changes in the intestinal parasite infracommunities in wild-living rufous mouse lemurs (Microcebus rufus) from Ranomafana National Park in southeastern Madagascar from 2010 to 2012. We used high-throughput barcoding of the 18S rRNA gene to interrogate parasite community structure. Our results show that in these nematode communities, there were two frequently occurring putative species and four rarer putative species. All putative species were randomly distributed over host individuals and they did not occur in clear temporal patterns. For the individuals caught in at least two different years, there was high turnover of putative species and high variation in fecal egg counts. Our study shows that while there was remarkable variation in infracommunities over time, the component community was relatively stable. Nevertheless, the patterns of prevalence varied substantially between years in each component community.

Teat Morphology Characterization With 3D Imaging.

The objective of this study was to visualize, in a novel way, the morphological characteristics of bovine teats to gain a better understanding of the detailed teat morphology. We applied silicone casting and 3D digital imaging in order to obtain a more detailed image of the teat structures than that seen in previous studies. Teat samples from 65 dairy cows over 12 months of age were obtained from cows slaughtered at an abattoir. The teats were classified according to the teat condition scoring used in Finland and the lengths of the teat canals were measured. Silicone molds were made from the external teat surface surrounding the teat orifice and from the internal surface of the teat consisting of the papillary duct, Fürstenberg's rosette, and distal part of the teat cistern. The external and internal surface molds of 35 cows were scanned with a 3D laser scanner. The molds and the digital 3D models were used to evaluate internal and external teat surface morphology. A number of measurements were taken from the silicone molds. The 3D models reproduced the morphology of the teats accurately with high repeatability. Breed didn't correlate with the teat classification score. The rosette was found to have significant variation in its size and number of mucosal folds. The internal surface morphology of the rosette did not correlate with the external surface morphology of the teat implying that it is relatively independent of milking parameters that may impact the teat canal and the external surface of the teat.

Relationships between learning strategies, stress, and study success among first-year veterinary students during an educational transition phase.

We investigated the relationships between stress, learning strategies, and study success among first-year veterinary students at the very beginning of their veterinary studies. The study was carried out during the first course on macroscopic anatomy (osteology), which students have in the past found to be exceptionally stressful. Students (N=45) completed a questionnaire concerning their self-reported views on stress and learning strategies, which were compared with their self-reported written-test scores. Participants who had previously gained university credits did not have significantly better test scores, but they achieved the learning goals with significantly less stress than other participants. Previous experience of university study helped students not only to adjust to a new type of course content and to achieve the learning goal of the osteology course, but also to cope with the stress experienced from taking concurrently running courses. Of the respondents who specifically named factors relating to self-regulation and modification of their learning strategy, all had gained prior credits. These students were able to use their study time efficiently and adjust their schedules according to the course demands.

Students as teachers in an anatomy dissection course.

One way to improve students' learning outcomes and well-being is to change teaching practices to allow students to become more active participants. We used an anatomy dissection course to test a cooperative group work method in which first-year veterinary students took turns leading their peer group and were each responsible for teaching the anatomy of a particular topographic region. The important blood vessels, lymphatic system, and nerves of each region of the body were covered. Students felt that exploration of the entire topographic region helped them to acquire a comprehensive understanding of the respiratory apparatus and the cardiovascular and nervous systems. Assigning individual tasks to each group member resulted in sharing the workload equally. Open-ended comments revealed that support from other group members was important for the students' learning experience, but the results also offered insight into a lack of constructive criticism. While teaching was considered challenging, and even a stress factor that hindered learning for some students, group work was generally held to be supportive of learning. The results suggest that more thorough instruction of students in their group work and in their individual tasks is required. Some students experienced difficulty in expressing their concerns openly and in seeking guidance from teachers, demonstrating the need for further investigation regarding students' self-regulation skills. Comments from the open-ended responses suggest that use of a cooperative learning method in anatomy dissection courses not only deepens student understanding of a subject but also offers first-year students an opportunity to practice the generic skills that will be needed in their future profession.

Free-ranging Eurasian lynx (Lynx lynx) as host of Toxoplasma gondii in Finland.

We investigated the presence of Toxoplasma gondii infections in Eurasian lynx (Lynx lynx) in Finland by analyzing samples from 337 lynx that were legally hunted during the 2010-2011 season and by performing a retrospective nationwide database search of postmortem toxoplasmosis diagnoses in this species. We detected specific anti-T. gondii IgG antibodies in 290 (86.1%) of the 337 lynx. The method used was a direct agglutination test, and samples positive at the used dilution 1:40 were defined as antibody positive. Older lynx had 14.3 times higher odds of being antibody-positive than did lynx of the presumed age of 7-10 mo, and lynx weighing >15 kg had 16.7 times higher odds of being antibody positive than did those ≤ 15 kg. Lynx from the southwest were more often antibody positive, with an odds ratio 6.3, than lynx from the northeast. None of the 332 fecal samples available was positive for the presence of T. gondii-like oocysts with a quantitative MgSO4 flotation technique, and none of the 167 free-ranging Eurasian lynx examined postmortem by veterinary pathologists from January 2000 to May 2010 had died from toxoplasmosis. Although Finnish lynx were confirmed to commonly encounter T. gondii, we found no evidence of an ongoing contribution to the environmental oocyst burden nor of the lynx dying from the infection.

Endoparasites of the Eurasian lynx (Lynx lynx) in Finland.

We sampled 339 fecal samples, 296 intestines, and 82 lungs from 371 lynx hunted during the 2010-2011 season in Finland. The fecal samples were analyzed for endoparasites by a quantitative flotation method, and helminths from intestines were studied morphologically, while lungs were investigated for pulmonary parasites. From fecal samples, eggs and oocysts of at least 6 different endoparasite species were identified, with a mean of 1.5 (range 0-4) parasite species per host. In the intestines, at least 4 different helminth species were found, with the mean of 2.0 (range 1-4) species per infected host. The prevalence of eggs in feces and the prevalence of worms in intestines were 71% and 93% for Toxocara cati , 29% and 68% for Taenia spp., and 5% and 2% for Diphyllobothrium sp., respectively. Only eggs were detected for Capillaria sp. (46%) and Uncinaria sp. (0.6%) nematodes, and only adults were detected for Mesocestoides sp. cestodes (0.3%). Significant positive correlations were evident between the number of T. cati (r = 0.664; P = 0.01) and Diphyllobothrium sp. (r = 0.645; P = 0.01) eggs per gram of feces and adult worms detected in intestine. In addition to the metazoan parasites, protozoan Isospora sp. oocysts were also found (0.6%). Pulmonary samples were all negative for parasites. These data demonstrate that lynx commonly harbor various endoparasites, some of which are zoonotic.

Environmental change and disease dynamics: effects of intensive forest management on Puumala hantavirus infection in boreal bank vole populations.

Intensive management of Fennoscandian forests has led to a mosaic of woodlands in different stages of maturity. The main rodent host of the zoonotic Puumala hantavirus (PUUV) is the bank vole (Myodes glareolus), a species that can be found in all woodlands and especially mature forests. We investigated the influence of forest age structure on PUUV infection dynamics in bank voles. Over four years, we trapped small mammals twice a year in a forest network of different succession stages in Northern Finland. Our study sites represented four forest age classes from young (4 to 30 years) to mature (over 100 years) forests. We show that PUUV-infected bank voles occurred commonly in all forest age classes, but peaked in mature forests. The probability of an individual bank vole to be PUUV infected was positively related to concurrent host population density. However, when population density was controlled for, a relatively higher infection rate was observed in voles trapped in younger forests. Furthermore, we found evidence of a "dilution effect" in that the infection probability was negatively associated with the simultaneous density of other small mammals during the breeding season. Our results suggest that younger forests created by intensive management can reduce hantaviral load in the environment, but PUUV is common in woodlands of all ages. As such, the Fennoscandian forest landscape represents a significant reservoir and source of hantaviral infection in humans.