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

Abstract

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.

Fig. 1

Vorderwald × Montbéliarde cattle showing complete cleft lip and jaw (CLJ). a Case 3 shows a complete right-sided CLJ with a lateral curvature of the mandibles to the left side. b Case 8 shows a complete left-sided CLJ without lateral curvature of the mandibles. c Case 6 shows a complete bilateral CLJ with a slight lateral curvature of the mandibles to the left side

Fig. 2

Computed tomography scanning images of the head for Vorderwald × Montbéliarde cattle. a Case 3 with a complete right-sided cleft lip and jaw, b case 8 with a complete left-sided CLJ and c case 6 with a complete bilateral CLJ. Dorsal view of the skull excluding the mandibles

Fig. 3

Computed tomography scanning images of the head for Vorderwald × Montbéliarde cattle showing the ventral view of the skull excluding the mandibles. a Case 3 shows a complete right-sided CLJ. b Case 8 shows a complete left-sided CLJ. c Case 6 shows a complete bilateral CLJ

Fig. 4

Computed tomography scanning images of the head for Vorderwald × Montbéliarde cattle affected by cleft lip and jaw (CLJ) showing the lateral curvature of the mandibles. a Case 3 shows a complete right-sided CLJ with a lateral curvature of the mandibles to the left side. b Case 8 shows a complete left-sided CLJ without lateral curvature of the mandibles. c Case 6 shows a complete bilateral CLJ with a slight lateral curvature of the mandibles to the left side

Fig. 5

Roofs of the oral cavity of a control and a cleft lip and jaw (CLJ) affected Vorderwald × Montbéliarde cattle. a Normally formed roof of an oral cavity of a control without a CLJ. In the foreground, the papilla incisiva is visible on the dental plate. Behind the dental plate, the connection to the hard palate and the rugae palatinae on both sides are visible. b The oral cavity of Vorderwald × Montbéliarde cattle (case 8) with a left-sided CLJ is shown. Approximately 1/3 of the dental plate is missing on the left. On the adjacent hard palate, rugae palatinae are missing