Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-23T13:13:21.928Z Has data issue: false hasContentIssue false

Studies of the permanent incisor eruption, and body development, of the Large East African Zebu (Boran): 1. The ages at first appearance of the incisors, lengths of the incisor eruption period, and sources of variation

Published online by Cambridge University Press:  27 March 2009

A. B. Carles
Affiliation:
Department of Animal Production, University of NairobiP.O. Box 29053, Kabete, Kenya.
K. Meidie Lampkin
Affiliation:
East African Veterinary Research OrganizationP.O. Kabete, Kenya.

Summary

Observations were made of the ages at first appearance of each pair of permanent incisors (‘eruption age’), and the time from first appearance to full eruption of each pair (‘eruption period’), for Large East African Zebu cattle (Boran). For females the eruption ages were found to be 108·5±9·9 weeks, 137·2±12·9, 165·7±15·8, and 200·9±18·2 for incisor pairs one to four respectively; for steers the figures were 104·3±7·9, 130·3±10·6, 154·6±13·2, and 180·9±14·0; and for bulls 103·3±8·6, 127·6±11·2, 151·0±12·9, and 181·2±15·7. Females were significantly different from steers (P < 0.01), but steers not significantly different from bulls, for all four incisor pairs.

The distributions of eruption ages for each sex and pair can be considered as Normal for statistical purposes. There is a tendency for eruption to be asymmetrical after the first pair, with the right tooth preceding the left.

Correlations of eruption ages between adjacent pairs are of the order of 0·80 for all pairs and sexes; they decrease progressively as pairs intervene to 0·55 for the first and fourth pairs. Partial correlations approach zero when any intermediate pair is held constant. These results indicate that the whole eruption process is highly interdependent.

Evaluation of age grouping and estimations from the presence of incisors showed that this technique, although limited on its own, is still the best developmental trait for ageing. A steer with one incisor pair present had a probability of 0·108 of being the same age or older than one with two pairs. The ages of steers with one and two incisor pairs present were 115·7±12·05 and 140·7±14·27 weeks respectively.

Heritabilities of eruption age, for the various incisor pairs, varied between 0·91±0·33 and 0·43±0·25 for females, and 0·87±0·37 and 0·11±0·59 for steers.

Sources of environmental variation examined were variation between and within years, both of which were of the same order and a very small proportion of the total variation. The maternal environment had a small effect, probably specifically associated with milk consumption, which had a correlation of —0·22 for females and —0·12 for steers (P < 0.01) with the eruption age of the first incisor pair.

Eruption periods for females were 5·1±2·8 weeks, 5·7±3·8, 6·8±4·5, and 8·8±5·6 for pairs one to four respectively; for steers 4·6±2·6, 4·9±2·9, 5·6±3·8, 7·2±5·3; and for bulls 4·9±2·2, 4·8±2·7, 5·7±3·8, 6·0±3·3. Females were significantly slower than steers (P < 0·05) for the first three incisor pairs only, while steers did not differ significantly from bulls for any pair.

The distribution of eruption periods was positively skewed, and the correlations between pairs ranged between 0·0 and 0·35. Correlations of eruption ages and periods within incisor pairs lay between 0·50 and 0·95.

Variation of eruption periods was not significant within years, but was between years, and arose almost entirely from the first two experimental years. The majority of the heritabilities approached zero.

Growth rate differences probably accounted for the differences in eruption periods between the four incisor pairs and the three sexes. The cause of asymmetry of eruption was not the source of the variation in eruption times within incisor pairs, the first tooth consistently having a greater eruption time.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1977

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Andrews, A. H. (1973). A survey of the relationship between age and the development of the anterior teeth in cattle. Veterinary Record 92, 275–82.CrossRefGoogle ScholarPubMed
Brown, G. T. (1949). Dentition as Indicative of the Age of the Animals of the Farm, 9th ed. London: Murray. (Cited by Wiener & Donald, 1955.)Google Scholar
Brown, W. A. B., Christofferson, P. V., Massler, M. & Weiss, M. B. (1960). Postnatal tooth development in cattle. American Journal of Veterinary Research 21, 734.Google ScholarPubMed
Butler, P. M. (1939). Studies of mammalian dentition — differentiation of the post canine dentition. Proceedings of the Zoological Society, London B 109, 1.CrossRefGoogle Scholar
Caughley, G. (1965). Horn rings and tooth eruption as criteria of age in the Himalayan Thar, Hemitragus jemlahicus. New Zealand Journal of Science 8, 333–51.Google Scholar
Chieffi, A., Pawa, O. M. & Veiga, J. S. (1948). Ages of eruption of permanent incisors of Gir and Nellore (bred in Brazil). Revue deFaculty Medicine Veterinary, Sdo Paulo 3, 251–69.Google Scholar
Coohran, W. G. (1952). The x2 test of goodness of fit. Annals of Mathematics and Statistics 23, 315–45. (Cited by Steele & Torrie (1960), p. 350.)CrossRefGoogle Scholar
Cochran, W. G. (1954). Some methods for strengthening the common x2 tests. Biometrics 10, 417–51. (Cited by Steele & Torrie (1960), p. 350.)CrossRefGoogle Scholar
Dickerson, G. E. (1960). Techniques for research in quantitative animal genetics. Techniques and Procedures in Animal Production Research, p. 74. Beltsville: American Society of Animal Production.Google Scholar
Edmund, A. G. (1960). Tooth replacement phenomena in lower vertebrates. Life Sciences Division, Royal Ontario Museum, Toronto, contribution 52.CrossRefGoogle Scholar
Franklin, M. C. (1950). The influence of diet on dental development in the sheep. Bulletin of Commonwealth Scientific and Industrial Research, Australia, no. 252, p. 34. (Veterinary Bulletin 21, no. 791.)Google Scholar
Garn, S. M., Lewis, A. B. & Kerewsky, R. S. (1965). Genetic, nutritional and maturational correlates of dental development. Journal of Dental Research 44, 228.CrossRefGoogle ScholarPubMed
Garn, S. M., Lewis, A. B., Koski, K. & Polacheck, D. L. (1958). Sex difference in tooth calcification. Journal of Dental Research 37, 561.CrossRefGoogle ScholarPubMed
Garn, S. M., Lewis, A. B. & Polacheck, D. L. (1959). Variability of teeth formation. Journal of Dental Research 38, 135.CrossRefGoogle Scholar
Hammond, J. (1932). Growth and Development of Mutton Qualities in Sheep. Edinburgh: Oliver and Boyd.Google Scholar
Ishaque, S. M., Khan, A. W. & Khan, M. A. (1967). Studies on the eruption of teeth in buffalo, Sahiwal and Dajal cattle in Pakistan. West Pakistan Journal of Agricultural Research 5, 143–54.Google Scholar
Joubert, D. M. (1956). On the effect of breed and nutritional plane on dentitition in the cow. Proceedings of the British Society of Animal Production, III. (Veterinary Bulletin 28, no. 251.)Google Scholar
Kikule, S. B. (1953). Age changes in the teeth of zebu cattle. East African Agricultural and Forestry Journal 19, 86–8.CrossRefGoogle Scholar
Lall, H. K. (1948). Dentition in Indian cattle. Indian Journal of Veterinary Science 18, 37.Google Scholar
Lampkin, G. H. & Lampkin, K. (1960a). Studies on the production of beef from zebu cattle in East Africa. I. A description of the Muguga herd. Journal of Agricultural Science, Cambridge 55, 229–31.CrossRefGoogle Scholar
Lampkin, G. H. & Lampkin, K. (1960b). Studies on the production of beef from zebu cattle in East Africa. II. Milk production in suckled cows and its effect on calf growth. Journal of Agricultural Science, Cambridge 55, 233–9.CrossRefGoogle Scholar
Lawson, D. D., Nixon, G. S., Noble, H. W. & Weipers, W. L. (1967). Development and eruption of the canine dentition. British Veterinary Journal 123, 2630.CrossRefGoogle Scholar
Mason, I. L. & Maule, J. P. (1960). The Indigenous Livestock of Eastern and Southern Africa, p. 57. Farnham Royal: Commonwealth Agricultural Bureaux.Google Scholar
McCance, R. A., Owens, P. D. A. & Tonge, C. H. (1968). Severe undernutrition in growing and adult animals. 18. The effects of rehabilitation on the teeth and jaw of pigs. British Journal of Nutrition 22, 357–68.CrossRefGoogle Scholar
McRoberts, M. R., Hill, R. & Dalgarno, A. C. (1965). The effects of diets deficient in phosphorus, and vitamin D, or calcium, on the skeleton and teeth of growing sheep. I. The mineral status of the skeleton and clinical appearance of the teeth. Journal of Agricultural Science, Cambridge 65, 110.CrossRefGoogle Scholar
Meyn, K. (1967). Weidemasfcversuche mit ostafrikanischen Zeburindern und Herefords, durchgefuhrt auf der Forschungsstation Muguga im Hochland Kenias. Ph.D. thesis, University of Gottingen.Google Scholar
Needham, A. E. (1964). The Growth Process in Animals, p. 19. London: Pitman.Google Scholar
Robertshaw, D. & Katongole, C. B. (1969). Adrenocortical activity and intermediary metabolism of Bos indicus and Bos taurus in the high altitude (2000 m) tropics. International Journal of Biometeorology 13, 101.Google Scholar
Robertson, A. (1959). Experimental design in the evaluation of genetic parameters. Biometrics 15, 219–26.CrossRefGoogle Scholar
Simpson, M. J. & Wilson, L. L. (1971). Effects of breed, sire, sex and age on degree of molar development in yearling beef cattle. Growth 35, 183–9.Google ScholarPubMed
Sisson, S. & Grossman, J. D. (1962). The Anatomy of the Domestic Animals, 4th ed. revised. Philadelphia: Saunders.Google Scholar
Spinage, C. A. (1973). A review of the age determination of mammals by means of teeth, with special reference to Africa. East African Wildlife Journal 11, 165–87.CrossRefGoogle Scholar
Steenkamp, J. D. G. (1970). The effect of breed and nutritional plane on the chronology of teeth eruption in cattle. Rhodesian Journal of Agricultural Research 8, 313.Google Scholar
Tomes, C. S. (1923). A Manual of Dental Anatomy, 8th ed. (ed. Tims, H. W. Marett and Henry, C. Bowdler). London: Churchill. (Cited by Wiener & Donald, 1955.)Google Scholar
Tonge, C. H. & McCance, B. A. (1965). Severe undernutrition of growing and adult animals. 15. Mouth, jaws, and teeth of pigs. British Journal of Nutrition 19, 361–72.CrossRefGoogle ScholarPubMed
Tulloh, N. M. (1962). A study of the incisor teeth of beef cattle. Australian Journal of Agricultural Research 13, 350–61.CrossRefGoogle Scholar
Wenham, G. & Fowler, N. R. (1973). A radiographic study of age changes in the skull, mandible, and teeth of pigs. Journal of Agricultural Science, Cambridge 80, 451–61.CrossRefGoogle Scholar
Widdowson, E. M. & McCance, R. A. (1960). Some effects of accelerating growth. I. General somatic development. Proceedings of the Royal Society B 152, 188206.Google ScholarPubMed
Wiener, G. & Donald, H. P. (1955). A study of variation in twin cattle. IV. Emergence of permanent incisor teeth. Journal of Dairy Research 22, 127—37.CrossRefGoogle Scholar
Wiener, G. & Purser, A. F. (1957). The influence of four levels of feeding on the position and eruption of incisor teeth. Journal of Agricultural Science, Cambridge 49, 51–9.CrossRefGoogle Scholar
Youatt, W. (1834). Cattle, their Breeds, Management and Diseases. (Cited by Wiener & Donald, 1965.)CrossRefGoogle Scholar