CONGENITAL ABNORMALITIES IN CATTLE: THEII% ASSOCIATION WITH HEREDITARY AND ENVIRONMENTAL FACTORS 1 IV[. S. tIERSCHLER, N. S. FECtIttEIMER, AND L. O. GILMORE Department of Dairy Science, The Ohio State University, Columbus AND The Ohio Agricultural Experiment Station, Wooster SUi'~MARY The purpose of this paper is to indicate the frequency of congenital anom- Mies in cattle and to record data dealing with the influence of environmental and hereditary factors on their occurrence. Approximately 5,000 calves o~ the Holstein, Guernsey, and Jersey breeds were divided into normal and abnormM animals. Abnormality was defined as any anatomical defect observed by the cooperating dairymen. The abnormalities reported were divided into five major groups: general abnormalities, abnor- malities of ectodermal, mesodermal, and neurectodermal derivatives and calves born dead with no other observable defect. Environmental and genetic factors were tested for an association with the number of abnormal animals reported and the type of abnormality reported, by the chi-square test of independence; 6.26% of the calves born were abnormM. A significant association of sire, with the number of abnormal animals reported, was demonstrated. A highly significant association of twins and abnormal gestation length with the number of abnormal animals was shown. Twins were highly significantly associated with type of ab- normality reported, as was breed. No significant association was found between sex, number of services required for conception, breed, level of herd production or inbreeding, and the number of abnormal animals reported. No significant association could be shown between number of services required for conception or sex and type of abnormality reported. Congenital abnormalities are an economic burden to the dairyman. Every abnormal calf is one less replacement for cows that leave the herd. In addition, the birth of an abnormal calf may be accompanied by severe dystocia. The purpose of this paper is to indicate the frequency of congenital abnormalities in cattle and to record data dealing with the influence of environmental and hereditary factors on their occurrence. The problem of congenital abnormalities can be approached from two points of view. The diagnosis and study of the genetic history of individual abnormalities may be undertaken. This method has been used in the early reports of abnormalities, reported in cattle for over 100 yr (4). In 1934, a list of eleven abnormM- ities occurring in cattle was published (9). This list has been increased by nnmerous authors Received for publication July 20, 1962. 1 Journal Article :No. 63-62, The Ohio Agricul- tural Experiment Station, Wooster, Ohio. so that the most recent review (18) included 34 lethals and 14 sublethals. Other reviewers (5, 7, 8, 15) have considered the general prob- lem of abnornlalities and have grouped reports by type of tissue affected, while trying to find some connection among the anomalies cited. lViead, Gregory, and Regan (12) tested six sires at random in the California Experiment Station herd and reported eight deleterious re- cessive genes carried among these bulls. The Production Division of the Milk Marketing Board of Great Britain (13), on the other hand, has reported few recessively inherited abnornmlities carried per bull for the A.I. centers of Great Britain. All congenital abnormalities are not genet- ically initiated. They have been attributed to disease (10), poisons (15), vitamin deficiency (6), and other environmental faetors, as well as interactions of genes and the environment. Bruin (2, 3), with information on 601 abnor- malities affecting 337 cattle, concluded that gen- eral environment and inherited influences af- fected either the frequency of abnormal ani- 1493
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