Craniofacial skeletal abnormalities in anomalous calves with clefts of the face

Simultaneous Occurrence of Hypospadias and Bilateral Cleft Lip and Jaw in a Crossbred Calf: Clinical, Computer Tomographic, and Genomic Characterization

Congenital abnormalities in animals, including abnormalities of the cleft lip and jaw and hypospadias have been reported in all domesticated species. They are a major concern for breeders due to the increased economic loss they entail. In this article, we described a congenital bilateral cheilognathoschisis (cleft lip and jaw) with campylognathia in association with penile hypospadias and preputial hypoplasia with failure of preputial fusion in a Bos taurus crossbred Piedmontese × Wagyu calf. Clinical examination, computed tomography, and whole genome sequencing were performed to describe and identify a possible cause of the abnormalities. Clinical examination revealed a bilateral cheilognathoschisis of approximately 4 cm in length and 3 cm in width in the widest part, with computer tomography analyses confirming the bilateral absence of the processus nasalis of the incisive bone and the lateral deviation of the processus palatinus towards the left side. Genomic data analyses identified 13 mutations with a high impact on the products of the following overlapped genes: ACVR1, ADGRA2, BHMT2, BMPR1B, CCDC8, CDH1, EGF, F13A1, GSTP1, IRF6, MMP14, MYBPHL, and PHC2 with ADGRA2, EGF, F13A1, GSTP1, and IRF6 having mutations in a homozygous state. The whole genome investigation indicates the involvement of multiple genes in the birth defects observed in this case.

De novo ZIC2 frameshift variant associated with frontonasal dysplasia in a Limousin calf

Background

Bovine frontonasal dysplasias like arhinencephaly, synophthalmia, cyclopia and anophthalmia are sporadic congenital facial malformations. In this study, computed tomography, necropsy, histopathological examinations and whole genome sequencing on an Illumina NextSeq500 were performed to characterize a stillborn Limousin calf with frontonasal dysplasia. In order to identify private genetic and structural variants, we screened whole genome sequencing data of the affected calf and unaffected relatives including parents, a maternal and paternal halfsibling.

Results

The stillborn calf exhibited severe craniofacial malformations. Nose and maxilla were absent, mandibles were upwardly curved and a median cleft palate was evident. Eyes, optic nerve and orbital cavities were not developed and the rudimentary orbita showed hypotelorism. A defect centrally in the front skull covered with a membrane extended into the intracranial cavity. Aprosencephaly affected telencephalic and diencephalic structures and cerebellum. In addition, a shortened tail was seen. Filtering whole genome sequencing data revealed a private frameshift variant within the candidate gene ZIC2 in the affected calf. This variant was heterozygous mutant in this case and homozygous wild type in parents, half-siblings and controls.

Conclusions

We found a novel ZIC2 frameshift mutation in an aprosencephalic Limousin calf. The origin of this variant is most likely due to a de novo mutation in the germline of one parent or during very early embryonic development. To the authors’ best knowledge, this is the first identified mutation in cattle associated with bovine frontonasal dysplasia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-020-07350-y.

Multiple Cephalic Malformations in a Calf

Congenital malformations of the central nervous system (CNS) can affect the CNS alone or the CNS and craniofacial structures. Here, we report an unusual and complex congenital cephalic malformation observed in a 3-day-old male crossbreed calf. Clinical examination disclosed a dome-shaped cranial vault, a flat face with a short snout, a median cleft lip, and increased intraorbital distance. The frontal region of the head was remarkable for a fluctuant, sac-like protrusion covered with haired skin. Neurologic findings suggested a multifocal intracranial lesion affecting the prosencephalon and the central vestibular system. While pathological and histopathological findings posited for a presumptive diagnosis of either hydranencephaly or holoprosencephaly associated with multiple congenital facial abnormalities, not all the findings could be definitely attributed to either of the two encephalic malformations alone. To our knowledge, a similar combination of severe congenital abnormalities affecting both the CNS and the craniofacial structures has not been reported in calves to date.

Lobar holoprosencephaly with craniofacial defects in a Friesian calf: A case report

BACKGROUND

Holoprosencephaly is a forebrain deformity that results from varying degrees of separation failure of cerebral hemispheres. The condition is classified based on the degree of non-separation of the hemispheres which, in turn, determines its severity. Holoprosencephaly is usually accompanied by craniofacial defects whose severity tends to reflect the extent of brain deformities. In humans, holoprosencephaly is one of the commonest congenital brain anomalies but in animals, reported cases are scarce. The condition has multifactorial aetiology that involves interactions between several genetic and environmental factors.

CASE PRESENTATION

A 4-day-old female Friesian calf with a deformed face was reported to the Faculty of veterinary medicine and surgery, Egerton University. The calf and the dam were sired by the same bull. On clinical and radiographic examination, the calf had a short snout that curved dorsally with bilateral cleft lip, right-sided cleft jaw and a largely absent primary palate. Anatomopathological examination revealed brain deformities which included ventral fusion of frontal lobes of cerebral hemispheres, large merged lateral ventricles without septum pellucidum and fornix, hypoplastic corpus callosum, high degree of non-separation between diencephalic structures, poorly developed hippocampal formation and hypoplastic olfactory lobe, optic chiasma, and nerve.

CONCLUSION

The case was confirmed as lobar holoprosencephaly based on characteristic anatomopathological findings. The aetiology of the defects in the present case could not be determined though they are thought to be either a result of recessive inheritance or exposure to teratogenic steroid alkaloids through materials fed to the dam during early pregnancy.

Breeding experiments and genome-wide association analysis elucidate two genetically different forms of non-syndromic congenital cleft lip and jaw in Vorderwald × Montbéliarde cattle

Non-syndromic congenital cleft lip and jaw (CLJ) is a condition reported in Vorderwald × Montbéliarde cattle. The objective of the present study was to perform a genome-wide association study (GWAS) for 10 CLJ-affected and 50 unaffected Vorderwald × Montbéliarde cattle using the bovine Illumina high density bead chip to identify loci for this condition. Phenotypic classification of CLJ was based on a detailed recording of orofacial structures using computed tomography. A breeding experiment among CLJ-affected Vorderwald × Montbéliarde cattle and CLJ-affected Vorderwald × Montbéliarde cattle with unaffected Holsteins confirmed recessive inheritance and different loci for bilateral or left-sided versus right-sided CLJ. The GWAS for the five cases with right-sided CLJ gave a genome-wide signal on bovine chromosome (BTA) 29 at 16 Mb. For the four left-sided and one bilateral CLJ case, a genome-wide significant association was identified on BTA4 at 32 Mb. Two different loci are very likely to be involved in CLJ in Vorderwald × Montbéliarde cattle because experimental matings among affected cows and bulls with different types of CLJ did not result in CLJ-affected progeny, and in addition, two different loci were also found through GWAS and mapped on two different bovine chromosomes. Validation in 346 Vorderwald × Montbéliarde cattle for the highly associated SNPs on BTA4 and 29 gave ratios of 33/346 (0.095, BTA4) and 6/346 (0.017, BTA29) homozygous mutant genotypes. Further studies should elucidate the responsible mutations underlying the different types of CLJ in Vorderwald × Montbéliarde cattle.

Phenotypic classification of variability of non-syndromic congenital cleft lip and jaw in Vorderwald × Montbéliarde cattle

Background

Non-syndromic congenital cleft lip and jaw (CLJ) is a condition reported in several cattle breeds, but a detailed classification system does not exist for cattle. The objective of the present study was to describe the phenotypic variability of this orofacial malformation in Vorderwald × Montbéliarde cattle. For this purpose, a classification system of CLJ was developed on examination of five orofacial structures: (1) lips, (2) the processus (proc.) nasalis of the os incisivum, (3) the dental plate with adjacent segments of the hard palate, (4) the facial bones (os incisivum, os maxillare, os nasale and os palatinum) and (5) the mandibles. Each structure was given a score reflecting the degree of the lesion from absent (score 0) to severe.

Results

Nine cases were included in the study and they shared absence of the abaxial rostral part of the processus (proc.) nasalis of the os incisivum, partial loss of the rugae palatinae and the dental plate. A sigmoid curvature of the rostral lower jaw as well as a lateral deviation of the face and rostral lower jaw was highly variable in their expression. These deformations were present in eight of nine cases. In addition to the complete CLJ, three animals had an incomplete CLJ on the contralateral site with variable defects of the rostral part of the proc. nasalis of the os incisivum.

Conclusions

A complete CLJ is obviously accompanied by a loss of parts of the proc. nasalis of the os incisivum. Extent and localization of the missing parts of the proc. nasalis were similar in all cases. A precise classification of the various CLJ forms is necessary.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-015-0177-0) contains supplementary material, which is available to authorized users.

Craniomaxillofacial abnormalities in dogs with congenital palatal defects: computed tomographic findings

OBJECTIVE

To evaluate craniomaxillofacial abnormalities in dogs with congenital palatal defects.

STUDY DESIGN

Retrospective computed tomography (CT) study.

ANIMALS

Dogs with congenital palatal defects (n = 9).

METHODS

Medical records and CT reports (1995-2012) were searched for dogs with a diagnosis of cleft palate that had a CT study. Data retrieved were: breed, age, sex, weight, physical examination, and laboratory findings, number of previous palate surgeries, and oral/dental examination findings with the diagnosis of the cleft for each dog. CT studies of the head were reviewed on a structure-by-structure basis.

RESULTS

Tympanic bullae were most commonly found to be abnormal (8 dogs), followed by nasal turbinates (6), nasal septum, vomer, cribriform plate (4), frontal sinuses, and lateral ventricles (3). Other abnormalities were related to occlusion, teeth, incisive bones, maxillary bones, mandibles, hyoid apparatus, cranial bones, and nasopharynx. The soft tissue defect of the cleft was always smaller than the bony defect.

CONCLUSIONS

Craniomaxillofacial abnormalities in dogs with congenital palatal defects are common and some of these may negatively affect the quality of life. Importantly for surgical planning, the soft tissue component of the cleft may underestimate the extent of the bony defect, especially in failed repairs.

Right-sided cleft lip and jaw in a family of Vorderwald × Montbéliarde cattle

A congenital unilateral cleft lip and jaw in association with campylognathia to the opposite side was identified in a family of Vorderwald×Montbéliarde cattle. Clinical examination, radiography and computed tomography revealed similar types and degrees of orofacial abnormality in three affected animals from different farms. Digital radiographs and computed tomography demonstrated absence of the rostral segment of the incisive bone in association with sigmoid curvature of the rostral lower jaw and campylognathia to the left side. All three affected animals could be traced back to a common ancestor, a Montbéliarde bull, who had sons and grandsons used for in-crossing in Vorderwald cattle. The affected animals were inbred on Montbéliarde sires, with inbreeding coefficients of 0.39% in one calf and 6.25% in two calves. Pedigree analysis supported the hypothesis of an autosomal recessive mode of inheritance.