Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
58 Indian Vet. J., September 2013, 90 (9) : 58 - 59 Snorter Dwarf Calf with Brachygnathia Inferior Condition A.Velavan, S. Sivaraman, K. Krishnakumar and J. Rajagopal Veterinary College and Research Institute, Orathanadu, Thanjavur – 614625 (Received : 03-09-2012; The congenital defects were recorded as 0.5 to 1.0 per cent in cattle population (Newman et al., 1999). The calves with congenital anomalies are often a result of environmental factors, genetic factors or both. Among congenital anomalies, dwarsm is a rare condition. Snorter dwarsm in calves is one of the congenital defects with short, blocky appearance with deformed bone growth in the nasal passages (parrot mouth) and have difculty in breathing (Grifth et al., 1987; Woollen, 1993). Snorter dwarf calf is rarely reported in Tamil Nadu. This paper describes the congenital defects of Snorter dwarf calf and its occurrence in Thanjavur district, Tamil Nadu, India. Case History and Observations A ten days old female Jersey cross calf was presented to Teaching Veterinary clinical complex, Veterinary College and Research Institute, Orathanadu with the complaint of not taking milk properly since birth. Clinical examination revealed that the calf was stunted in growth. The history revealed that a normal Jersey cross cow was allowed for natural service with a non-descriptive bull and delivered a dwarf calf. Past breeding histories of both dam and sire revealed no dwarf calves. There was no further breeding history of the bull since it was castrated immediately after the birth of this dwarf calf. The calf had normal posture and gait. Defection and urination were normal. Detailed musculo skeletal system examination revealed stunted growth of both appendicular and axial skeletal bones. Mandibular bone showed brachygnathia inferior or parrot mouth (Fig ). The calf had 9.5 kg bw and 43 cm height at shoulder level. Due to improperly developed mandible, the calf was not able to suckle the milk. So, the poor prognosis was explained to the owner. 1 Corresponding author : Email : [email protected] Accepted : 19-12-2012) Treatment and Discussion There are three common types of dwarsm as Snorter, long head and compress dwarfism caused by both environment and genetics (Pahnish et al., 1995a). Snorter dwarsm causes short, blocky appearance with deformed bone growth in the nasal passages which causes difculty in breathing. This dwarsm is inherited as a simple recessive trait. Long head dwarsm causes small size but does not affect the bone growth in nasal passages. This dwarsm is inherited as a simple recessive trait. Compress dwarsm is inherited as incomplete dominance. An individual with one compress gene and one normal gene has an extremely compressed body conformation. The individual with two compress Fig. 1: Snorter dwarf calf showing its parrot mouth (Note : incomplete development of mandible and protrusion of tongue outside the mandible). The Indian Veterinary Journal (September, 2013) A.Velavan et al. genes is a dwarf and the calf dies at or soon after birth. The cause for these abnormalities could not be determined. The typical brachynathia inferior (parrot mouth) was identied in Holstein and Simmental breed calves due to polygenic inheritance (Girfth et al., loc. cit; Woollen, loc. cit). Based on the above ndings the present case could be classied as Snorter dwarf calf. Viral infection, teratogenic drugs and alkaloids of plants often lead to craniofacial malformations associated with brachgnathia inferior. Schalles et al., (1914) reported that parrot mouth (brachygnathia inferior) in cattle was inherited as a simple recessive trait. The more common cause of teeth and denture pads not meeting is a quantitative trait caused by several sets of genes. This can cause either an under or over shot jaw with varying degrees of expression. Progeny testing done by Pahnish et al., (1995) reported that dwarsm must be considered as a breeding problem. It cannot be eliminated by changing basic rations or introducing feed supplements. So, considering all these above ndings, we could conclude that this particular calf dwarsm was purely due to genetic effect and not environmental effect. 59 Summary A ten days old Jersey cross calf was presented for improper milk intake. Clinical examination revealed improper development of mandible (brachygnathia inferior) and stunted growth of the calf. So the calf was identied as Snorter dwarf calf. To prevent further dwarsm from the same parents, both the sire and dam were stopped from further breeding. References Grifth, J.W., Hobbs, B.A. and Manders, E.K. (1987) Cleft palate, brachygnathia inferior and mandibular oligodontia in a Holstein calf. J. Comp. Pathol., 97 : 95-99. Newman, S.J., Bailey, T.L., Jones, J.C., DiGrassie, W.A. and Whittier, W.D. (1999) Multiple congenital anomalies in a calf. J. Vet. Diagn Invest., 11 : 368-371. Pahnish, O.F., Stanley, E.B. and Saey, C.E. (1955) The inheritance of a dwarf anomaly in beef cattle. Jour. Anim. Sci., 14 : 200. Pahnish, O.F., Stanley, E.B., Saey, C.E. and Roubicek, C.B. (1955) Dwarsm in beef cattle. The description, cause and control. Agricultural Experiment Station, University of Arizona, Tucson, Bulletin, 268 : 1-21. Schalles, R.R., Leipold, H.W. and McCraw, R.L. (1914) Congenital defects in cattle. In : Beef Cattle Handbook, pp 1-4. Woollen, N.E. (1993) Brachynathia in Simmental cattle. Agric Res. Serv., 71 : 183. INDIAN VETERINARY JOURNAL (IVJ) LIFE MEMBERSHIP Veterinarians are requested to become life members of Indian Veterinary Journal by paying `.5000/- as DD in favour of Editor, Indian Veterinary Journal, payable at Nandanam, Chamiers Road, Chennai. Furnish your qualication, designation, ofcial address and complete mailing address with pincode and email ID. Please note - The Life Membership is valid for only 10 years. The Indian Veterinary Journal (September, 2013)