Congenital localized cutaneous Langerhans cell histiocytosis in a Holstein calf.

Distinct solitary dermal nodules, either covered by an alopecic, or sometimes ulcerated, epidermis, were noticed on the head of a stillborn Holstein calf. The head was submitted for autopsy, and the nodules were found to consist of homogeneous, diffuse pale-yellow, soft-tissue masses with distinct margins that elevated the epidermis above the adjacent skin. Histologically, the dermal nodules were well-delineated on the deep margin approaching the cutaneous muscle and consisted of perivascular neoplastic infiltrates of round cells that in some places coalesced into sheets that extended into the dermis and subcutis. Neoplastic cells separated adnexa and collagen. Immunohistochemistry revealed intense tumor cell expression of vimentin, Iba1, E-cadherin, and CD204; expression of CD18 was faint. The masses were diagnosed as Langerhans cell histiocytosis. Congenital cutaneous Langerhans cell histiocytosis has not been reported previously in cattle, to our knowledge, and should be included in the differential diagnosis of congenital nodular skin lesions.

Environmental chemicals in dog testes reflect their geographical source and may be associated with altered pathology.

In humans and dogs, a temporal decline in semen quality and increased incidence of testicular cancer is hypothesised to be associated with exposure to anthropogenic chemicals, particularly during fetal development. Human studies suggest that differential exposures to environmental chemicals may be associated with geographical differences in male reproductive health. Here we investigate testicular chemical profiles and pathologies in dogs residing in the UK [West Midlands (WM), East Midlands (EM), South East (SE)], Denmark (Copenhagen) and Finland (Vantaa). Testes, surplus from routine castrations, contained region specific differences in relative concentrations of diethylhexyl phthalate (DEHP), polybrominated diphenyl ethers (PBDE) and polychlorinated biphenyls (PCB). Relative to UK regions, testes from dogs living in Finland and Denmark had higher concentrations of PBDE and lower concentrations of DEHP and PCBs. Regional differences in the UK in PCB concentrations were also observed. Dog testes from Finland had fewer pathologies, reduced testicular area stained for Sertoli and germ cells and evidence of reduced cellular proliferation. Since the geographical differences in testis pathologies in dogs parallel reports of regional differences in human testicular cancer, we postulate that this may reflect chemical effects within the testis and that this may be related to environmental influences on male reproductive function.

Seroprevalence for Brucella spp. in Baltic ringed seals (Phoca hispida) and East Greenland harp (Pagophilus groenlandicus) and hooded (Cystophora cristata) seals.

Zoonotic infections transmitted from marine mammals to humans in the Baltic and European Arctic are of unknown significance, despite given considerable potential for transmission due to local hunt. Here we present results of an initial screening for Brucella spp. in Arctic and Baltic seal species. Baltic ringed seals (Pusa hispida, n = 12) sampled in October 2015 and Greenland Sea harp seals (Pagophilus groenlandicus, n = 6) and hooded seals (Cystophora cristata, n = 3) sampled in March 2015 were serologically analysed for antibodies against Brucella spp. The serological analyses were performed using the Rose Bengal Test (RBT) followed by a confirmatory testing of RBT-positive samples by a competitive-enzyme linked immunosorbent assay (C-ELISA). Two of the Baltic ringed seals (a juvenile male and a juvenile female) were seropositive thus indicating previous exposure to a Brucella spp. The findings indicate that ringed seals in the Baltic ecosystem may be exposed to and possibly infected by Brucella spp. No seropositive individuals were detected among the Greenland harp and hooded seals. Although our initial screening shows a zoonotic hazard to Baltic locals, a more in-depth epidemiological investigation is needed in order to determine the human risk associated with this.

A de novo missense mutation of FGFR2 causes facial dysplasia syndrome in Holstein cattle.

BACKGROUND: Surveillance for bovine genetic diseases in Denmark identified a hitherto unreported congenital syndrome occurring among progeny of a Holstein sire used for artificial breeding. A genetic aetiology due to a dominant inheritance with incomplete penetrance or a mosaic germline mutation was suspected as all recorded cases were progeny of the same sire. Detailed investigations were performed to characterize the syndrome and to reveal its cause. RESULTS: Seven malformed calves were submitted examination. All cases shared a common morphology with the most striking lesions being severe facial dysplasia and complete prolapse of the eyes. Consequently the syndrome was named facial dysplasia syndrome (FDS). Furthermore, extensive brain malformations, including microencephaly, hydrocephalus, lobation of the cerebral hemispheres and compression of the brain were present. Subsequent data analysis of progeny of the sire revealed that around 0.5% of his offspring suffered from FDS. High density single nucleotide polymorphism (SNP) genotyping data of the seven cases and their parents were used to map the defect in the bovine genome. Significant genetic linkage was obtained for three regions, including chromosome 26 where whole genome sequencing of a case-parent trio revealed two de novo variants perfectly associated with the disease: an intronic SNP in the DMBT1 gene and a single non-synonymous variant in the FGFR2 gene. This FGFR2 missense variant (c.927G>T) affects a gene encoding a member of the fibroblast growth factor receptor family, where amino acid sequence is highly conserved between members and across species. It is predicted to change an evolutionary conserved tryptophan into a cysteine residue (p.Trp309Cys). Both variant alleles were proven to result from de novo mutation events in the germline of the sire. CONCLUSIONS: FDS is a novel genetic disorder of Holstein cattle. Mutations in the human FGFR2 gene are associated with various dominant inherited craniofacial dysostosis syndromes. Given the phenotypic similarities in FDS affected calves, the genetic mapping and absence of further high impact variants in the critical genome regions, it is highly likely that the missense mutation in the FGFR2 gene caused the FDS phenotype in a dominant mode of inheritance.

Genital tract lesions in sexually mature Göttingen minipigs during the initial stages of experimental vaginal infection with Chlamydia trachomatis serovar D.

BACKGROUND: Chlamydia is one of the most common sexually transmitted diseases in humans worldwide, causing chronic lesions in the reproductive tract. Due to its often asymptomatic course, there is limited knowledge about the initial changes in the genital tract following infection. This study employs a novel sexually mature minipig model to investigate the initial histopathological changes following vaginal infection with Chlamydia trachomatis serovar D. RESULTS: A vaginal inoculation resulted in an infection primarily affecting the lower genital tract. The histopathological changes were characterized by a subepithelial inflammation consisting of neutrophils and mononuclear cells, followed by an increase in the number of plasma cells within the sub-epithelial stroma of the vagina. Detection of Chlamydia was associated with expression of cyclooxygenase-2 and interleukin-8 by superficial epithelial cells. The infection was self-limiting, with a duration of 7 days. CONCLUSION: Neutrophils, plasma cells and IL-8 have been linked with Chlamydia genital infection of unknown duration in human patients. In this study, we observe a similar pattern of local immune response/inflammation following experimental inoculation suggesting this porcine model shows promise as a model for translational chlamydia research.

Lethal chondrodysplasia in a family of Holstein cattle is associated with a de novo splice site variant of COL2A1.

BACKGROUND: Lethal chondrodysplasia (bulldog syndrome) is a well-known congenital syndrome in cattle and occurs sporadically in many breeds. In 2015, it was noticed that about 12% of the offspring of the phenotypically normal Danish Holstein sire VH Cadiz Captivo showed chondrodysplasia resembling previously reported bulldog calves. Pedigree analysis of affected calves did not display obvious inbreeding to a common ancestor, suggesting the causative allele was not a rare recessive. The normal phenotype of the sire suggested a dominant inheritance with incomplete penetrance or a mosaic mutation. RESULTS: Three malformed calves were examined by necropsy, histopathology, radiology, and computed tomography scanning. These calves were morphologically similar and displayed severe disproportionate dwarfism and reduced body weight. The syndrome was characterized by shortening and compression of the body due to reduced length of the spine and the long bones of the limbs. The vicerocranium had severe dysplasia and palatoschisis. The bones had small irregular diaphyses and enlarged epiphyses consisting only of chondroid tissue. The sire and a total of four affected half-sib offspring and their dams were genotyped with the BovineHD SNP array to map the defect in the genome. Significant genetic linkage was obtained for several regions of the bovine genome including chromosome 5 where whole genome sequencing of an affected calf revealed a COL2A1 point mutation (g.32473300 G > A). This private sequence variant was predicted to affect splicing as it altered the conserved splice donor sequence GT at the 5'-end of COL2A1 intron 36, which was changed to AT. All five available cases carried the mutant allele in heterozygous state and all five dams were homozygous wild type. The sire VH Cadiz Captivo was shown to be a gonadal and somatic mosaic as assessed by the presence of the mutant allele at levels of about 5% in peripheral blood and 15% in semen. CONCLUSIONS: The phenotypic and genetic findings are comparable to a previously reported COL2A1 missense mutation underlying lethal chondrodysplasia in the offspring of a mosaic French Holstein sire (Igale Masc). The identified independent spontaneous splice site variant in COL2A1 most likely caused chondrodysplasia and must have occurred during the early foetal development of the sire. This study provides a first example of a dominant COL2A1 splice site variant as candidate causal mutation of a severe lethal chondrodysplasia phenotype. Germline mosaicism is a relatively frequent mechanism in the origin of genetic disorders and explains the prevalence of a certain fraction of affected offspring. Paternal dominant de novo mutations are a risk in cattle breeding, especially because the ratio of defective offspring may be very high and be associated with significant animal welfare problems.

Congenital infiltrative lipomas and retroperitoneal perirenal lipomas in a calf.

BACKGROUND: Congenital lipocytic tumours have rarely been reported in cattle. Lipomas are benign tumours, but infiltrative lipomas have significant health implications due to their aggressive infiltrative growth pattern. CASE PRESENTATION: A calf was born with skeletal malformations and soft tissue proliferations, primarily on the external thoracic wall. The calf was euthanized for welfare reasons and submitted for post mortem examination. Necropsy, histopathology and post mortem computed tomography scanning revealed two types of lipocytic tumours. Widespread infiltrative lipomas were present in the muscles and connective tissues along the vertebral column and diffusely invaded the external soft tissues of the right thoracic wall. The neoplastic lipocytes had invaded intervertebral spaces thus causing congenital vertebral malformations, and further invaded the vertebral canal and the bone marrow of coccygeal vertebrae. Periosteal localization of the tumour was associated with costal hyperostosis. Two large retroperitoneal lipomas enclosed the kidneys and occupied much of the abdominal space. CONCLUSION: The development of congenital bone malformation in this calf illustrates the severe consequences of the infiltrative and aggressive growth of infiltrative lipomas during foetal development. The congenital retroperitoneal lipomas occupied a large part of abdominal cavity, but did not invade the adjacent tissues. Due to their large size, perirenal lipomas should be considered in calves with distended abdomen, even in cases without other signs of tumours.

A hereditary disposition for bovine peripheral nerve sheath tumors in Danish Holstein cattle.

BACKGROUND: Peripheral nerve sheath tumors (PNSTs) are frequently found in Danish cattle at slaughter. Bovine PNSTs share several gross and histopathological characteristics with the PNSTs in humans with heritable neurofibromatosis syndromes. The aim of the present study was to investigate a possible hereditary disposition to PNSTs in dairy cattle by statistical analysis performed on data from 567 cattle with PNSTs. Furthermore, a preliminary genome-wide association study (GWAS) was performed on DNA isolated from 28 affected and 28 non-affected Holstein cows to identify loci in the bovine genome involved in the development of PNSTs. RESULTS: PNSTs were significantly more common in the Danish Holstein breed than in other breeds with 0.49% of Danish Holsteins slaughtered during an eight-year-period having PNSTs. PNSTs also occurred significantly more frequently in the offspring of some specific Holstein sires. Examination of three generation pedigrees showed that these sires were genetically related through a widely used US Holstein sire. The PNSTs included in GWAS were histologically classified as neurofibroma-schwannoma (43%), schwannoma (36%) and neurofibroma (21%) and derived from Holstein cows with multiple PNSTs. A single SNP on chromosome 27 reached genome-wide significance. CONCLUSIONS: Gross and histological characteristics of bovine PNSTs are comparable to PNSTs in humans (schwannomatosis). Danish Holsteins are genetically disposed to develop PNSTs but the examined materials are insufficient to allow determination of the mode of inheritance.

Perosomus elumbis in Danish Holstein cattle.

BACKGROUND: Perosomus elumbis (PE) is a congenital defect that has been observed sporadically in Holstein cattle for many years. However, several cases have been reported in recent years and this may indicate an unrecognised spread of a mutant allele in the Holstein population worldwide. Two cases in Danish Holstein calves are reported to provide details on the phenotype. CASE PRESENTATION: Two full-term Holstein calves were born after assisted delivery due to dystocia with breech presentation. External morphological examination indicated that the lumbar, sacral and coccygeal vertebrae were absent and the abdominal region was just present as a floppy sac covered by skin and enclosing the abdominal organs. The hind limbs were hypoplastic with bilateral symmetric arthrogryposis and muscular atrophy. Radiographs, computed tomography scan and necropsy confirmed these findings. The caudal part of the thoracic spinal cord showed myelodysplasia. A range of abdominal organ malformations were found at necropsy. Inbreeding was not found during genealogical examination, but remote shared ancestors were present in the pedigrees. CONCLUSION: The addition of these further cases of PE to the in recent years reported record of cases should draw more attention to this defect in the Holstein breed. PE may be an emerging genetic defect in the Holstein population worldwide and cases should be sampled to enable genetic mapping of the gene possibly underlying the disease. PE cases seem to be associated with a high risk of dystocia due to increased rate of breech presentation.

Histologic and bacteriologic findings in valvular endocarditis of slaughter-age pigs.

Endocarditis lesions from 117 slaughter pigs were examined pathologically and etiologically in addition to 90 control hearts with cardiac valves. Lesions were located on the valves; however, the lesions had extended to the walls in 21 cases (18%). Lesions predominated on the mitral valve (59%). A total of 28 cases, from which no growth was obtained or a contamination flora was grown, were screened by fluorescence in situ hybridization (FISH) for bacteria (general bacterial probe) and probes specific for Streptococcus suis and Erysipelothrix rhusiopathiae, respectively. Using FISH, an additional 10 cases of endocarditis due to S. suis and E. rhusiopathiae were disclosed. Within lesions, streptococci predominated (53%) followed by E. rhusiopathiae (30%). Distinct features of both the lesions and the shape and localization of bacterial colonies were related to streptococci and E. rhusiopathiae. The propensity for streptococci to be localized on more than 1 valve in single hearts may be because S. suis-infected pigs tend to have been infected for a longer period compared with E. rhusiopathiae. Mineralization of endocarditis lesions was significantly associated with infection by streptococci, and was seen in 71% of the cases, whereas it was present in only 28% of lesions caused by E. rhusiopathiae. In addition, areas with mineralization were significantly correlated to the presence of a granulomatous reaction. Granulomatous endocarditis is likely a result of a foreign body reaction due to dystrophic mineralization. Local proliferation of valvular endothelial cells, found in 9 hearts in the current study, may increase the risk of developing thrombosing endocarditis in pigs.

Intravenous inoculation of Staphylococcus aureus in pigs induces severe sepsis as indicated by increased hypercoagulability and hepatic dysfunction.

Nine pigs were inoculated intravenously once or twice with 10(8) Staphylococcus aureus per kilogram body weight and sacrificed 12, 24 and 48 h after inoculation. Three sham-infected pigs served as controls. Blood samples were taken for bacteriology, haematology and clinical chemistry. A necropsy was carried out and tissue samples were collected for bacteriology and histology. The onset of clinical disease was seen at 7-8 h after inoculation. The blood bacterial counts remained low throughout the study. All infected pigs developed sepsis characterized by fever, neutrophilia, increased levels of C-reactive protein (CRP) and IL-6, and decreased levels of serum iron. The CRP and IL-6 levels peaked at 36 h, whereas IL-1beta and tumour necrosis factor-alpha showed no obvious changes. Thromboelastography showed increasing hypercoagulability from 12 h and onwards, whereas the platelet numbers declined slightly throughout the experiment. The levels of serum aspartate aminotransferase and bilirubin were elevated at 24 and 36 h. In conclusion, sepsis and severe sepsis were induced as evidenced by dysfunction of the blood clotting system and the liver.

Congenital bovine spinal dysmyelination is caused by a missense mutation in the SPAST gene.

Bovine spinal dysmyelination (BSD) is a recessive congenital neurodegenerative disease in cattle (Bos taurus) characterized by pathological changes of the myelin sheaths in the spinal cord. The occurrence of BSD is a longstanding problem in the American Brown Swiss (ABS) breed and in several European cattle breeds upgraded with ABS. Here, we show that the disease locus on bovine chromosome 11 harbors the SPAST gene that, when mutated, is responsible for the human disorder hereditary spastic paraplegia (HSP). Initially, SPAST encoding Spastin was considered a less likely candidate gene for BSD since the modes of inheritance as well as the time of onset and severity of symptoms differ widely between HSP and BSD. However, sequence analysis of the bovine SPAST gene in affected animals identified a R560Q substitution at a position in the ATPase domain of the Spastin protein that is invariant from insects to mammals. Interestingly, three different mutations in human SPAST gene at the equivalent position are known to cause HSP. To explore this observation further, we genotyped more than 3,100 animals of various cattle breeds and found that the glutamine allele exclusively occurred in breeds upgraded with ABS. Furthermore, all confirmed BSD carriers were heterozygous, while all affected calves were homozygous for the glutamine allele consistent with recessive transmission of the underlying mutation and complete penetrance in the homozygous state. Subsequent analysis of recombinant Spastin in vitro showed that the R560Q substitution severely impaired the ATPase activity, demonstrating a causal relationship between the SPAST mutation and BSD.

Morphological variation of "complex vertebral malformation" in Holstein calves.

A study was performed to investigate the morphological expression of the inherited syndrome "complex vertebral malformation" (CVM) in Holstein calves. A total of 107 late-term aborted, premature, or neonatal calves suspected of having CVM were necropsied and retrospectively analyzed for the causal mutation in the gene SLC35A3. Sixty-two calves were homozygous affected, 16 were heterozygous, and 29 were homozygous normal. Calves affected by CVM were growth retarded. Vertebral lesions identified by radiography were present in 61 cases, of which 58 also had costal malformation. Malformation of the head, primarily in the form of dysplasia or palatoschisis, was present in 15 cases. Bilateral symmetric flexion of the carpal and metacarpophalangeal joints was present in all cases, whereas posterior arthrogryposis was found in 54 cases. Interventricular septal defects occurred in 33 calves, often in combination with other cardiac malformations. A wide spectrum of additional malformations was found. Other congenital syndromes were in most cases distinguishable from CVM on a morphological basis. However, a calf with a prenatal infection with bovine virus diarrhea virus constituted a phenocopy. The study demonstrated that the morphological expression of CVM is wide, but certain aspects, i.e., growth retardation, vertebral malformation, and symmetric arthrogryposis, are almost constant findings. However, cases without vertebral defects and phenocopies constitute a diagnostic problem. A presumptive diagnosis of CVM can in most cases be based on necropsy findings combined with information on descent and paternal CVM genotype, whereas a definitive diagnosis requires genotyping.

Familial chondrodysplasia in Holstein calves.

After the release of a report from France on the occurrence of malformed calves genetically related to a Holstein sire, a study was performed to characterize the defect. Danish breeders were encouraged to submit defective progeny of the sire for laboratory examination. Four cases were submitted, whereas a fifth case was only reported. Lesions in affected calves were analogous, with disproportionate growth retardation characterized by fascial dysplasia and shortening of the vertebral column and the abaxial skeleton. Endochondral osteogenesis was disturbed with disorganization of epiphyseal plate chondrocytes, a lesion consistent with generalized chondrodysplasia. Based on morphology, the defect was grouped as a "Dexter bulldog type". A genetic etiology was suspected as cases occurred in a familial pattern. Genealogical evaluation revealed several common ancestors belonging to widely used breeding lines of US Holstein, but because of the extensive use of these sires, their presence in the pedigrees of affected calves might be accidental. Further studies are needed to determine the mode of inheritance.