The performance of Brahman-Shorthorn and Sahiwal-Shorthorn beef cattle in the dry tropics of northern Queensland .5. Scrotal circumference, temperament, ectoparasite resistance, and the genetics of growth and other traits in bulls

Fordyce, G., Howitt, C. J., Holroyd, R. G., O'Rourke, P. K. and Entwistle, K. W. (1996) The performance of Brahman-Shorthorn and Sahiwal-Shorthorn beef cattle in the dry tropics of northern Queensland .5. Scrotal circumference, temperament, ectoparasite resistance, and the genetics of growth and other traits in bulls. Australian Journal of Experimental Agriculture, 36 1: 9-17. doi:10.1071/EA9960009


Author Fordyce, G.
Howitt, C. J.
Holroyd, R. G.
O'Rourke, P. K.
Entwistle, K. W.
Title The performance of Brahman-Shorthorn and Sahiwal-Shorthorn beef cattle in the dry tropics of northern Queensland .5. Scrotal circumference, temperament, ectoparasite resistance, and the genetics of growth and other traits in bulls
Journal name Australian Journal of Experimental Agriculture   Check publisher's open access policy
ISSN 0816-1089
1446-5574
Publication date 1996
Sub-type Article (original research)
DOI 10.1071/EA9960009
Volume 36
Issue 1
Start page 9
End page 17
Total pages 9
Place of publication Collingwood, VIC, Australia
Publisher CSIRO
Language eng
Formatted abstract
The genetics of growth to 24 months, scrotal circumference (SC) at 24 months and temperaments at 6, 12 and 18 months in 7 year groups of F 2 et seq., 1/2 Brahman, 1/2 Sahiwal, 3/4 Brahman and 3/4 Sahiwal bulls were investigated in the dry tropics of northern Queensland. Cattle tick (Boophilus microplus) and buffalo fly (Haematobia irritans exigua) resistance were also assessed at 24 months. Scrotal circumference at 24 months was highest in 1/2 Sahiwal crosses (28 cm v. 26-27 cm; P<0.05) with pronounced variation between years (24-31 cm; P<0.05). Temperaments (TEM score; flight distance) were generally poorest in 3/4 Sahiwal crosses (P<0.05). Bulls of 1/2 Bos indicus content were twice as susceptible as 3/4 crosses to tick infestations (P<0.05). There were no genotype differences in natural buffalo fly infestations. Temperaments, tick resistance and buffalo fly resistance all had no consistent significant relationships with either each other or with weights or growth rates to 24 months. Paternal half-sib estimates of heritabilities across all genotypes were generally moderate for weight (0.20-0.36), growth rates (0.08-0.46), and SC (0.32), low for TEM score (0.08-0.14), and high for flight distance (0.32-0.70). The genetic correlations (r G) between growth rates in both dry and wet seasons after weaning were high (≥0.9); however, the r G of weaning weight with post-weaning seasonal growth rates to 24 months were consistently negative (-0.09 to -0.71; P>0.05). The r G of SC with post-weaning growth rates were negative (-0.4 to -0.8). The r G of SC with weights up to 18 months were not significantly different to zero, but tended to be negative with weight at 24 months.
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: Queensland Alliance for Agriculture and Food Innovation
School of Veterinary Science Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 17 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 0 times in Scopus Article
Google Scholar Search Google Scholar
Created: Mon, 07 Mar 2011, 15:04:11 EST