Hostname: page-component-84b7d79bbc-l82ql Total loading time: 0 Render date: 2024-07-29T20:51:53.610Z Has data issue: false hasContentIssue false
  • English
  • Français

Reproductive rates and milk yield of Kenana cattle in Sudan

Published online by Cambridge University Press:  27 March 2009

K. A. Alim
K. A. Alim
Affiliation:
Department of Animal Production, Khartoum, Sudan
Get access Rights & Permissions [Opens in a new window]

Extract

An analysis has been made of the reproductive rates and milk yield of Kenana cattle in a closed dairy herd in Sudan.

The average age at first calving was 38·4 months and calvings were most frequent between September and December.

The average length of productive herd life of cows was 5·42 lactations.

The average interval between successive calvings was 395 days, and this was influenced by years and age.

The mean generation interval was 6·72 years.

The average milk yield in 224 days was 338 gal. with a standard deviation of 152 gal.

There was a close relationship between milk yield and lactation length; r = 0·866 ± 0·013.

Milk yield increased by age until the fourth lactation when it was about 137% of the first lactation. The rate of increase in yield between first and second lactation was highest and amounted to 22%.

Year of record had a pronounced effect on milk yield.

Month of calving had a slight effect on milk yield.

The repeatability estimates of single records milk yield, calving intervals, lactation periods and dry periods were 0·432 ± 0·046, 0·058 ± 0·059, 0·192 ± 0·058 and 0·069 ± 0·065, respectively.

The increase in repeatability estimates between earlier and later successive milk yield records was accompanied by a decrease in the coefficients of variation of these records.

The heritability of a single record milk yield was 0·239 ± 0·245.

The rate of annual genetic superiority in milk yield of dams of cows and dams of bulls was found to be 0·74% of the herd average.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 55 , Issue 2 , October 1960 , pp. 183 - 188
Copyright
Copyright © Cambridge University Press 1960

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

REFERENCES

Alim, K. A. (1953). Nature, Lond., 171, 755.CrossRefGoogle Scholar
Alim, K. A. (1953). Canad. J. Agric. Sci. 33, 606.Google Scholar
Alim, K. A. (1957). Emp. J. Exp. Agric. 25, 229.Google Scholar
Alim, K. A. & Ahmed, I. A. (1954). Emp. J. Exp. Agric. 22, 37.Google Scholar
Asdell, S. A. (1952). A regional approach to problems of fertility and breeding efficiency in dairy cattle. Rep. 2nd Intro. Congr. Path. Anim. Reprod. Art. Insem. 2, 7.Google Scholar
Ashpaq, M. & Mason, I. L. (1954). Emp. J. Exp. Agric. 22, 161.Google Scholar
Boyns, B. M. (1947). Emp. J. Exp. Agric. 15, 27.Google Scholar
Carneiro, G. G. & Lush, J. L. (1954). J. Dairy Sci. 37, 1145.CrossRefGoogle Scholar
Dickerson, G. E. (1940). J. Agric. Res. 61, 561.Google Scholar
Dickerson, G. E. & Hazel, L. N. (1944). J. Agric. Res. 67, 459.Google Scholar
Hattersley, M. C. (1951). E. Afr. Agric. J. 17, 27.Google Scholar
Johansson, I. (1949). 5th Int. Congr. Anim. Husbandry, Paris, p. 273.Google Scholar
Johansson, I. (1950). Anim. Breed. Abstr. 18, 1.Google Scholar
Johansson, I. & Hansson, A. (1940). K. Lantbr Akad. Tidskr. (Stockholm), 79, No. 6½, 127 pp.Google Scholar
Joshi, N. R. & Phillips, R. W. (1953). F.A.O. Agric. Stud. no. 19.Google Scholar
Legates, J. E. (1954). J. Anim. Sci. 13, 81.CrossRefGoogle Scholar
Lush, J. L. (1940). Proc. Amer. Soc. Anim. Prod. 32, 293.Google Scholar
Lush, J. L. (1947). Animal Breeding Plans (3rd ed.). Ames: Iowa State College Press.Google Scholar
Lush, J. L. & Strauss, F. S. (1942). J. Dairy Sci. 25, 975.CrossRefGoogle Scholar
Mahadevan, P. (1951). J. Agric. Sci. 41, 80.CrossRefGoogle Scholar
McLaughlin, E. A. (1955). Emp. J. Exp. Agric. 23, 188.Google Scholar
Ragab, M. T., Asker, A. A. & Hilmy, S. A. (1954). Indian J. Dairy Sci. 7, 171.Google Scholar
Ragab, M. T., Asker, A. A. & Hilmy, S. A. (1956). Indian J. Dairy Sci. 9, 53.Google Scholar
Rendel, J. M. & Robertson, Alan (1950). J. Genetics, 50, 1.CrossRefGoogle Scholar
Rendel, J. M., Robertson, Alan et al. (1957). J. Agric. Sci. 48, 426.CrossRefGoogle Scholar
Robertson, Alan (1950). A preliminary report on the herd of Fulani Cattle at Shika, Nigeria. Conf. Impr. Livestock Trop. Conditions, Edinburgh (mimeographed).Google Scholar
Sanders, H. G. (1928). J. Agric. Sci. 18, 46.CrossRefGoogle Scholar
Scott, J. R. (1947). Sudan Notes, 28, 181.Google Scholar
Snedecor, G. W. (1946). Statistical Methods (4th ed.). Ames: Iowa State College Press.Google ScholarPubMed
Stonaker, H. H. (1953). J. Dairy Sci. 36, 688.CrossRefGoogle Scholar